JP6907995B2 - Laminated electrode body - Google Patents

Description

The present invention relates to a laminated electrode body.

Patent Document 1 discloses a laminated electrode body in which a plurality of electrode sheets are laminated in the laminating direction. Such a laminated electrode body is, for example, a laminated electrode body in which a plurality of electrode sheets laminated in the laminating direction are pressure-bonded in the laminating direction. The electrode sheets constituting this laminated electrode body are all pressure-bonded to the electrode sheets adjacent to each other in the stacking direction. As the electrode sheet, for example, a positive electrode plate, a negative electrode plate, and a separator are laminated in the stacking direction and integrated.

Japanese Unexamined Patent Publication No. 2010-23201

By the way, the inventor of the present application presents a part of the laminated electrode body as described above in a plane direction orthogonal to the laminating direction (direction corresponding to the direction along the surface of the laminated electrode body) (for example,). In the first partial region and one or a plurality of other partial regions), a laminated electrode body in which electrode sheets adjacent to each other in the laminating direction are crimped is being studied. A part of the region is a region of a part of the entire surface of the laminated electrode body in a plan view of the laminated electrode body, and the stacking direction covers the entire surface of the laminated electrode body (from the front surface to the back surface of the laminated electrode body). It is a columnar region that extends.

Specifically, for example, in a laminated electrode body having a rectangular shape in a plan view, at the positions of four corners of a positive electrode mixture layer having a rectangular shape in a plan view included in the electrode sheet constituting the laminated electrode body in a plan view. It is a laminated electrode body in which electrode sheets adjacent to each other in the laminating direction are crimped. In this laminated electrode body, in a plan view, a first partial region exists at a position where one of the four corners of the positive electrode mixture layer exists, and a plurality of other regions exist at a position where the other three corners exist. There are partial regions (second partial region, third partial region, and fourth partial region). Such a laminated electrode body is manufactured, for example, as follows.

Specifically, first, a first laminated body in which two electrode sheets are laminated in the stacking direction is formed, and a first partial region of the first laminated body and one or a plurality of other partial regions (for example, for example). The second partial region, the third partial region, and the fourth partial region) are pressed in the stacking direction. Specifically, a portion of the surface (upper surface) of the first laminated body included in the first partial region is pressed in the stacking direction by a columnar first pressing member, and the surface (upper surface) of the first laminated body is pressed. A portion included in one or more of the other partial regions (for example, the second partial region, the third partial region, and the fourth partial region) is pressed by another columnar pressing member (for example, the second pressing member and the third pressing member). Press in the stacking direction by the member and the fourth pressing member). As a result, the two electrode sheets are crimped in the stacking direction in the first partial region and one or more other partial regions.

Here, of the two crimped electrode sheets, the pressed portion (the portion included in the first partial region and the portion included in one or a plurality of other partial regions) is referred to as the first crimped portion (first portion). (Parts included in the region) and one or more other crimping portions (parts included in one or more other partial regions). When the above-mentioned second partial region, third partial region, and fourth partial region are provided as one or more other partial regions, the one or multiple other crimping portions are the second crimping portion and the second crimping portion. It becomes the 3 crimping part and the 4th crimping part.

Next, one electrode sheet is laminated on the surface (upper surface) of the first laminated body in which the two electrode sheets are crimped to form a second laminated body in which the three electrode sheets are laminated in the stacking direction. Then, the first partial region of the second laminated body and one or more other partial regions are pressed in the stacking direction. Specifically, a portion of the surface (upper surface) of the second laminated body included in the first partial region is pressed in the stacking direction by the first pressing member, and one of the surfaces (upper surface) of the second laminated body is pressed. Alternatively, the portion included in the plurality of other partial regions is pressed in the stacking direction by another pressing member. As a result, the three electrode sheets are crimped in the stacking direction in the first partial region and one or more other partial regions. Of the three crimped electrode sheets, the pressed portion (the portion included in the first partial region and the portion included in one or a plurality of other partial regions) is one or more than the first crimped portion. It becomes another crimping part.

By crimping the plurality of electrode sheets one by one in this way, a laminated electrode body having a first crimping portion and one or a plurality of other crimping portions is manufactured. In this laminated electrode body, the first crimping portion and one or a plurality of other crimping portions are continuously present over the entire laminated electrode body in the stacking direction. That is, the first crimping portion and one or more other crimping portions each have a form (columnar shape) extending linearly from the front surface to the back surface of the laminated electrode body. In this laminated electrode body, all the electrode sheets constituting the laminated electrode body are crimped at the portion included in the first partial region and crimped at the portion included in one or a plurality of other partial regions.

However, in the laminated electrode body having the first crimping portion and one or more other crimping portions as described above, the first crimping portion and the one or more other crimping portions are greatly deformed. There was something. Specifically, a part of the electrode sheet (a portion included in the first crimping portion and one or a plurality of other crimping portions) constituting the laminated electrode body is greatly recessed toward the back surface side of the laminated electrode body. It was sometimes transformed into. In particular, a part of the electrode sheet (the portion included in the first crimping portion and one or a plurality of other crimping portions) located on the outermost surface side of the electrode sheets constituting the laminated electrode body is inside the stacking direction (in particular. The back surface side of the laminated electrode body) was sometimes deformed into a greatly recessed shape.

Further, as the number of electrode sheets (number of laminated sheets) is increased in order to obtain a high-capacity laminated electrode body, the depth of dent (dimension in the laminated direction) in which a part of the electrode sheets is recessed on the back surface side of the laminated electrode body becomes larger. Of these, the electrode sheet located on the outermost surface side of the laminated electrode body tends to have a particularly large dent depth (dimension in the stacking direction). If the electrode sheet constituting the laminated electrode body is partially deformed as described above, there is a possibility that the performance of the battery using the laminated electrode body is significantly deteriorated.

The present invention has been made in view of the present situation, and the first partial region (first crimping portion) of the electrode sheet constituting the laminated electrode body and one or more other partial regions (one or more). It is an object of the present invention to provide a laminated electrode body in which the amount of deformation (dent depth) of the laminated electrode body toward the back surface side is reduced in the other crimping portion).

One aspect of the present invention constitutes the laminated electrode body in a laminated electrode body in which a plurality of electrode sheets are laminated in the laminating direction, and the plurality of electrode sheets are crimped in the laminating direction. Each of the electrode sheets is crimped to the electrode sheet adjacent to the stacking direction, and the laminated electrode body is a part of the laminated electrode body in the plane direction orthogonal to the stacking direction. In the first partial region, the first crimping portion where the plurality of electrode sheets adjacent to the laminated direction are crimped, and the first partial region which is a part of the laminated electrode body in the plane direction. Has one or a plurality of other crimping portions to which the plurality of electrode sheets adjacent to each other in the stacking direction are crimped in different one or a plurality of other partial regions, and the first crimping portion is the laminated. Regarding the direction, the first partial region does not exist continuously over the entire laminated electrode body, but exists apart from the laminated electrode body with the electrode sheet in which the first partial region is not crimped, and each of the above. The other crimping portions do not exist continuously throughout the laminated electrode body in the laminating direction, and the electrode sheet in which the other partial regions are not crimped is sandwiched between the other crimping portions in the laminating direction. The other crimping portion, which is distant and any one of the one or more other crimping portions, includes the other partial region of the electrode sheet in which the first partial region is not crimped. It is an existing laminated electrode body.

The above-mentioned laminated electrode body is a laminated electrode body in which a plurality of electrode sheets are laminated in the laminating direction. More specifically, it is a laminated electrode body in which a plurality of electrode sheets laminated in the laminating direction are pressure-bonded in the laminating direction. The electrode sheets constituting the laminated electrode body are all pressure-bonded to the electrode sheets adjacent to each other in the stacking direction. As the electrode sheet, for example, a positive electrode plate, a negative electrode plate, and a separator are laminated in the stacking direction and integrated.

Further, the above-mentioned laminated electrode body has a stacking direction in a first partial region which is a partial region of the laminated electrode body in a plane direction orthogonal to the stacking direction (a direction corresponding to a direction along the surface of the laminated electrode body). It has a first crimping portion in which a plurality of electrode sheets adjacent to the above are crimped. The first partial region is a region of a part of the entire surface of the laminated electrode body in a plan view of the laminated electrode body, and the stacking direction covers the entire surface of the laminated electrode body (from the front surface to the back surface of the laminated electrode body). ) It is a columnar region that extends.

Further, the above-mentioned laminated electrode body is a partial region of the laminated electrode body in the plane direction, and is different from the first partial region (separated from the first partial region in the plane direction) or a plurality of other regions. In the partial region, it has one or more other crimped portions to which a plurality of electrode sheets adjacent to each other in the stacking direction are crimped. It should be noted that each of the other partial regions is a region of a part of the entire surface of the laminated electrode body (a range different from the first partial region) in the plan view of the laminated electrode body, and the laminated electrode body in the stacking direction. It is a columnar region extending over the entire surface (from the front surface to the back surface of the laminated electrode body).

Therefore, the above-mentioned laminated electrode body is a laminated electrode body in which a plurality of electrode sheets laminated in the stacking direction are crimped in a first partial region and one or a plurality of other partial regions.
The above-mentioned laminated electrode body is, for example, a laminated electrode body having a rectangular shape in a plan view, and the positive electrode mixture layer having a rectangular shape in a plan view included in the electrode sheet constituting the laminated electrode body in a plan view. A laminated electrode body in which electrode sheets adjacent to each other in the laminating direction are crimped at a corner position can be mentioned. In this laminated electrode body, in a plan view, the first partial region and the first crimping portion are present at a position where one of the four corners of the positive electrode mixture layer is present, and the other three corners are present. , There are a plurality of other partial regions (2nd partial region, 3rd partial region and 4th partial region), and a plurality of other crimping portions (2nd crimping portion, 3rd crimping portion and 4th crimping portion). do.

By the way, as described above, in the conventional laminated electrode body having the first crimping portion and one or a plurality of other crimping portions as described above, the first crimping portion and the one or a plurality of other crimping portions are used. However, it was sometimes greatly deformed. Specifically, a part of the electrode sheet (a portion included in the first crimping portion and one or a plurality of other crimping portions) constituting the laminated electrode body is greatly recessed toward the back surface side of the laminated electrode body. It was sometimes transformed into. In particular, a part of the electrode sheet (the portion included in the first crimping portion and one or a plurality of other crimping portions) located on the outermost surface side of the electrode sheets constituting the laminated electrode body is inside the stacking direction (in particular. The back surface side of the laminated electrode body) was sometimes deformed into a greatly recessed shape.

Further, as the number of electrode sheets (number of laminated sheets) is increased in order to obtain a high-capacity laminated electrode body, the depth of dent (dimension in the laminated direction) in which a part of the electrode sheets is recessed on the back surface side of the laminated electrode body becomes larger. Of these, the electrode sheet located on the outermost surface side of the laminated electrode body tends to have a particularly large dent depth (dimension in the stacking direction). If the electrode sheet constituting the laminated electrode body is partially deformed as described above, there is a possibility that the performance of the battery using the laminated electrode body is significantly deteriorated.

On the other hand, in the above-mentioned laminated electrode body (laminated electrode body according to one aspect of the present invention), the first crimping portion does not exist continuously over the entire laminated electrode body in the stacking direction (in other words, in other words. (Not in the form of being continuous from the front surface to the back surface of the laminated electrode body), the first partial region exists with an electrode sheet not crimped in between and separated in the stacking direction. That is, it is not that "all the electrode sheets constituting the laminated electrode body are crimped at the portion included in the first partial region", but a part of the electrode sheets among all the electrode sheets constituting the laminated electrode body. Is crimped at a portion included in the first partial region.

More specifically, among the electrode sheets constituting the laminated electrode body, a plurality of electrode sheets located on the surface side of the laminated electrode body or the first partial region with respect to the electrode sheet in which the first partial region is not crimped. A plurality of electrode sheets located on the back surface side of the laminated electrode body with respect to the electrode sheet not crimped, or a plurality of electrode sheets sandwiched between two electrode sheets in which the first partial region is not crimped. , Each is crimped at a portion included in the first partial region.

In such a laminated electrode body, even if the number of laminated electrode sheets is the same as that of the conventional laminated electrode body, the first partial region is as many as the number of electrode sheets in which the first partial region is not crimped. The number of electrode sheets crimped in is reduced. More specifically, the above-mentioned laminated electrode body is an electrode having a crimping portion connected in the stacking direction in the first partial region even if the number of laminated electrode sheets is the same as that of the conventional laminated electrode body. The number of sheets is reduced.

Here, "the number of electrode sheets having crimping portions continuous in the stacking direction (maximum number of sheets) in the first partial region" is defined in the pressing step of crimping a plurality of electrode sheets adjacent to each other in the stacking direction in the first partial region. One partial region corresponds to the maximum number of electrode sheets that are partially pressed and crimped. Therefore, when the above-mentioned laminated electrode body is manufactured, the maximum number of electrode sheets in which the first partial region is partially pressed and crimped is smaller than that in the case of manufacturing the conventional laminated electrode body. The amount of deformation (dent depth) of the first partial region (first crimping portion) of the electrode sheet can be reduced. In particular, in the first partial region (first crimping portion) of the electrode sheet located on the front surface side of the electrode sheets constituting the laminated electrode body, the amount of deformation (dent depth) of the laminated electrode body toward the back surface side is reduced. can do.

Further, in the above-mentioned laminated electrode body, each of the other crimping portions does not exist continuously over the entire laminated electrode body in the stacking direction (in other words, it is not a form in which the laminated electrode body is continuous from the front surface to the back surface). ), Each other partial region exists apart in the stacking direction with an electrode sheet that is not crimped in between. That is, in each of the other partial regions, not "all the electrode sheets constituting the laminated electrode body are crimped at the portion included in the other partial region", but all the electrodes constituting the laminated electrode body. A part of the electrode sheet is crimped at a portion included in the other partial region.

More specifically, in each of the other partial regions, among the electrode sheets constituting the laminated electrode body, a plurality of electrodes located on the surface side of the laminated electrode body with respect to the electrode sheet in which the other partial regions are not crimped. Between a plurality of electrode sheets located on the back surface side of the laminated electrode body with respect to the sheet or an electrode sheet in which other partial regions are not crimped, or between two electrode sheets in which other partial regions are not crimped. A plurality of sandwiched electrode sheets are crimped at a portion included in another partial region.

In such a laminated electrode body, even if the number of laminated electrode sheets is the same as that of the conventional laminated electrode body, the number of each of the electrode sheets is the same as the number of electrode sheets in which each other partial region is not crimped. The number of electrode sheets crimped in other partial regions is reduced. More specifically, the above-mentioned laminated electrode body has a crimping portion connected in the stacking direction in each of the other partial regions even if the number of laminated electrode sheets is the same as that of the conventional laminated electrode body. The number of electrode sheets to have is reduced.

Here, "the number of electrode sheets having crimping portions continuous in the stacking direction in other partial regions (maximum number of sheets)" is defined in the pressing step of crimping a plurality of electrode sheets adjacent to each other in the stacking direction in other partial regions. The partial area of is partially pressed and corresponds to the maximum number of electrode sheets to be crimped. Therefore, when the above-mentioned laminated electrode body is manufactured, the maximum number of electrode sheets in which the other partial regions are partially pressed and crimped is smaller than in the case of manufacturing the conventional laminated electrode body. The amount of deformation (dent depth) of the other partial region (other crimping portion) of the electrode sheet can be reduced. In particular, in the other partial region (other crimping portion) of the electrode sheet located on the front surface side of the laminated electrode body among the electrode sheets to which the other partial region is crimped, the amount of deformation of the laminated electrode body toward the back surface side ( Depth of dent) can be reduced.

As described above, the above-mentioned laminated electrode body includes a first partial region (first crimping portion) of the electrode sheet constituting the laminated electrode body, and one or a plurality of other partial regions (one or a plurality of other parts). In the crimping portion), the laminated electrode body has a reduced amount of deformation (dent depth) toward the back surface side of the laminated electrode body.

In the above-mentioned laminated electrode body, the other crimping portion (at least one other crimping portion) of any one or a plurality of other crimping portions is the electrode sheet in which the first partial region is not crimped. Exists including a subregion of. That is, the electrode sheet that is not crimped to the electrode sheet adjacent in the stacking direction in the first partial region is the other partial region of at least one other partial region (one or a plurality of other partial regions). ), It is crimped to the electrode sheet adjacent to the stacking direction. As a result, the above-mentioned laminated electrode body is "a laminated electrode body in which the electrode sheets constituting the laminated electrode body are all pressure-bonded to the electrode sheets adjacent to each other in the stacking direction".

It is a schematic plan view of the laminated electrode body which concerns on embodiment. It is a schematic cross-sectional view of the laminated electrode body, and is the EE cross-sectional view (or FF cross-sectional view) of FIG. It is the schematic cross-sectional view of the electrode sheet which constitutes a laminated electrode body. It is the schematic cross-sectional view of the negative electrode plate which constitutes an electrode sheet. It is the schematic cross-sectional view of the positive electrode plate which constitutes an electrode sheet. It is a figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is another figure explaining the press process which concerns on embodiment. It is the schematic sectional drawing of the laminated electrode body which concerns on embodiment. It is an enlarged view of the T part of FIG. 26. FIG. 26 is an enlarged view of the U portion of FIG. It is a figure explaining the conventional press process. It is another figure explaining the conventional pressing process. It is another figure explaining the conventional pressing process. It is another figure explaining the conventional pressing process. It is another figure explaining the conventional pressing process. It is another figure explaining the conventional pressing process. It is the S part enlarged view or the T part enlarged view of FIG. 34.

(Embodiment)
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic plan view of the laminated electrode body 50 according to the embodiment (a plan view of the surface 50b of the laminated electrode body 50 with respect to the stacking direction DH). FIG. 2 is a schematic cross-sectional view of the laminated electrode body 50, and is a cross-sectional view taken along the line EE (or a cross-sectional view taken along the line FF) of FIG. FIG. 3 is a schematic cross-sectional view of the electrode sheet 40 constituting the laminated electrode body 50. FIG. 4 is a schematic cross-sectional view of the negative electrode plate 10 constituting the electrode sheet 40. FIG. 5 is a schematic cross-sectional view of the positive electrode plate 30 constituting the electrode sheet 40. In the present embodiment, the length direction is BH, the width direction is CH, and the stacking direction (thickness direction) is DH for the laminated electrode body 50, the electrode sheet 40, the negative electrode plate 10, and the positive electrode plate 30. The stacking direction DH is a vertical direction in FIGS. 2 to 5 and a direction orthogonal to the paper surface in FIG.

First, the laminated electrode body 50 of this embodiment will be described. As shown in FIG. 1, the laminated electrode body 50 is a laminated electrode body having a rectangular shape in a plan view. As shown in FIG. 2, the laminated electrode body 50 is a laminated electrode body in which a plurality of electrode sheets 40 are laminated in the stacking direction DH, and the plurality of electrode sheets 40 are pressure-bonded in the stacking direction DH. Is. The electrode sheets 40 constituting the laminated electrode body 50 are all pressure-bonded to the electrode sheets 40 adjacent to the laminated electrode body DH. In FIG. 2, it is shown that there is no deformed portion in the first partial region A1 to the fourth partial region of the electrode sheet 40 constituting the laminated electrode body 50, but in reality, it is deformed. There is a part that is doing.

As shown in FIG. 3, the electrode sheet 40 constituting the laminated electrode body 50 is integrated by laminating the positive electrode plate 30, the negative electrode plate 10, and the separators 21 and 22 in the laminating direction DH (vertical direction in FIG. 3). It is an electrode. In addition, in order to firmly bond (adhere) the negative electrode plate 10 and the separators 21 and 22, a binder layer may be provided between the negative electrode plate 10 and the separators 21 and 22. Further, in order to firmly bond (adhere) the positive electrode plate 30 and the separator 21, a binder layer may be provided between the positive electrode plate 30 and the separator 21.

As shown in FIG. 4, the negative electrode plate 10 has a negative electrode current collecting foil 11 and a negative electrode mixture layer 13 formed on the front surface 11b and the back surface 11c of the negative electrode current collecting foil 11. As the negative electrode current collecting foil 11, for example, a copper foil can be used. Further, as the negative electrode mixture layer 13, for example, a mixture layer in which a negative electrode active material and a binder are mixed can be mentioned. Further, in the negative electrode plate 10, one end of the width direction CH (the right end in FIG. 3) has a negative electrode mixture layer 13 formed on the front surface 11b and the back surface 11c of the negative electrode current collector foil 11. The negative electrode current collecting foil 11 is exposed to the negative electrode exposed portion 10 m (see FIG. 3).

As shown in FIG. 5, the positive electrode plate 30 has a positive electrode current collecting foil 31 and a positive electrode mixture layer 33 formed on the front surface 31b and the back surface 31c of the positive electrode current collecting foil 31. As the positive electrode current collector foil 31, for example, an aluminum foil can be used. Further, as the positive electrode mixture layer 33, for example, a mixture layer in which a positive electrode active material, a conductive material, and a binder are mixed can be mentioned. Further, in the positive electrode plate 30, one end of the width direction CH (the left end in FIG. 3) has a positive electrode mixture layer 33 formed on the front surface 31b and the back surface 31c of the positive electrode current collector foil 31. The positive electrode current collecting foil 31 is exposed to the positive electrode exposed portion 30 m (see FIG. 3).

The separators 21 and 22 are made of a porous resin film having electrical insulation. The separators 21 and 22 are the same (same size) separators.

In the present embodiment, the area of the negative electrode mixture layer 13 (the area when the stacking direction DH is viewed in a plane) and the area of the separators 21 and 22 (the area when the lamination direction DH is viewed in a plane) are set to the positive mixture. It is made larger than the area of the layer 33 (the area when the stacking direction DH is viewed in a plan view) (see FIGS. 1 and 3). More specifically, the area of the separators 21 and 22 (the area when the stacking direction DH is viewed in a plane) is made larger than the area of the negative electrode mixture layer 13 (the area when the stacking direction DH is viewed in a plane). There is. Therefore, in the present embodiment, the magnitude relationship of (areas of separators 22 and 22)> (area of negative electrode mixture layer 13)> (area of positive electrode mixture layer 33) is satisfied.

Further, the laminated electrode body 50 of the present embodiment has a plane direction (direction corresponding to the direction along the surface 50b of the laminated electrode body 50, a direction along the paper surface in FIG. 1) perpendicular to the stacking direction DH of the laminated electrode body 50. In the first partial region A1 which is a partial region of the above, the first crimping portion 51 in which a plurality of electrode sheets 40 adjacent to the stacking direction DH are crimped is provided.

As shown in FIG. 1, the first partial region A1 is a region of a part of the entire surface 50b of the laminated electrode body 50 in a plan view of the laminated electrode body 50 (a solid circle in FIG. 1). Enclosed area). More specifically, the first partial region A1 is one corner (lower right corner in FIG. 1) of the four corners of the positive electrode mixture layer 33 having a rectangular shape in a plan view in the plan view of the laminated electrode body 50. It exists in the first corner portion 33b. As shown in FIG. 2, the first partial region A1 is a columnar region extending over the entire laminated electrode body 50 (from the front surface 50b to the back surface 50c of the laminated electrode body 50) in the stacking direction DH.

Further, the laminated electrode body 50 of the present embodiment is a partial region of the laminated electrode body 50 in the plane direction (direction along the paper surface in FIG. 1), and is a plurality of other regions different from the first partial region A1. In the partial region (second partial region A2, third partial region A3, and fourth partial region A4), a plurality of other crimping portions (second crimping portion) in which a plurality of electrode sheets 40 adjacent to the stacking direction DH are crimped. It has a portion 52, a third crimping portion 53, and a fourth crimping portion 54).

As shown in FIG. 1, the second partial region A2 is a region of a part of the entire surface 50b of the laminated electrode body 50 in a plan view of the laminated electrode body 50, and is a region of a part of the entire surface 50b of the laminated electrode body 50. In the plan view of the above, a region existing in the second corner 33c, which is one of the four corners (lower left corner in FIG. 1) of the rectangular positive electrode mixture layer 33 in the plan view (the circle of the broken line in FIG. 1). Area surrounded by). As shown in FIG. 2, the second partial region A2 is a columnar region extending over the entire laminated electrode body 50 (from the front surface 50b to the back surface 50c of the laminated electrode body 50) in the stacking direction DH.

Further, as shown in FIG. 1, the third partial region A3 is a region of a part of the entire surface 50b of the laminated electrode body 50 in a plan view of the laminated electrode body 50, and is a region of a part of the entire surface 50b of the laminated electrode body 50. In the plan view of the above, a region existing in the third corner 33d, which is one of the four corners of the positive electrode mixture layer 33 having a rectangular shape in the plan view (upper right corner in FIG. 1) (solid circle in FIG. 1). Area surrounded by). As shown in FIG. 2, the third partial region A3 is a columnar region extending over the entire laminated electrode body 50 (from the front surface 50b to the back surface 50c of the laminated electrode body 50) in the stacking direction DH.

Further, as shown in FIG. 1, the fourth partial region A4 is a region of a part of the entire surface 50b of the laminated electrode body 50 in a plan view of the laminated electrode body 50, and is a region of a part of the entire surface 50b of the laminated electrode body 50. In the plan view of, the region existing in the fourth corner 33e, which is one of the four corners (upper left corner in FIG. 1) of the rectangular positive electrode mixture layer 33 in the plan view (the circle of the broken line in FIG. 1). Area surrounded by). As shown in FIG. 2, the fourth partial region A4 is a columnar region extending over the entire laminated electrode body 50 (from the front surface 50b to the back surface 50c of the laminated electrode body 50) in the stacking direction DH.

Therefore, the laminated electrode body 50 of the present embodiment has a plurality of electrode sheets 40 laminated in the stacking direction DH in the first partial region A1, the second partial region A2, the third partial region A3, and the fourth partial region A4. Is a laminated electrode body that is crimped. More specifically, the laminated electrode body 50 of the present embodiment is a laminated electrode body having a rectangular shape in a plan view, and has a rectangular shape in a plan view included in the electrode sheet 40 constituting the laminated electrode body 50 in a plan view. At the positions of the four corners of the positive electrode mixture layer 33 (specifically, the first partial region A1, the second partial region A2, the third partial region A3, and the fourth partial region A4 existing at the four corners), in the stacking direction DH. It is a laminated electrode body in which adjacent electrode sheets 40 are crimped.

In the laminated electrode body 50 of the present embodiment, in a plan view, one of the four corners of the positive electrode mixture layer 33 is located at the position where the first corner 33b is present (lower right corner in FIG. 1). The second partial region A2 and the second crimping portion are located at the positions where the first partial region A1 and the first crimping portion 51 are present and the second corner portion 33c, which is another corner, is present (lower left corner in FIG. 1). The third partial region A3 and the third crimping portion 53 exist at the position where the portion 52 exists and the third corner portion 33d, which is another corner, exists (the upper right corner in FIG. 1), and the other 1 The fourth partial region A4 and the fourth crimping portion 54 are present at the positions where the fourth corner portion 33e, which is one corner, is present (the upper left corner in FIG. 1).

By the way, the inventor of the present application has conventionally manufactured a laminated electrode body as follows. Specifically, as shown in FIGS. 29 and 30, first, a first laminated body 201 in which two electrode sheets 40, 40 are laminated in the stacking direction DH is formed, and among the first laminated body 201, the first laminated body 201 is formed. The first partial regions A1 to the fourth partial regions A4 existing at the four corners of the positive electrode mixture layer 33 in a plan view are pressed in the stacking direction DH.

Note that FIG. 29 is a plan view of the surface side of the first laminated body 201 with respect to the stacking direction DH. 30 to 34 are views schematically showing the QQ cross section or the RR cross section of FIG. 29. In FIGS. 30 to 34, the cross-sectional shape of the electrode sheet 40 is simplified into a rectangular shape. Further, in FIGS. 30 to 34, the first crimping portion 251 and the second crimping portion 252, the third crimping portion 253, and the fourth crimping portion 254 are shown with cross hatching.

Specifically, as shown in FIGS. 29 and 30, with the first laminated body 201 mounted on the surface (upper surface) of the mounting table 78, the first of the surfaces (upper surface) of the first laminated body 201. The portion included in the first partial region A1 is pressed in the stacking direction DH by the columnar first pressing member 71, and the portion included in the second partial region A2 is pressed by the columnar second pressing member 72 in the stacking direction DH. The portion included in the third partial region A3 is pressed in the stacking direction DH by the columnar third pressing member 73, and the portion included in the fourth partial region A4 is pressed by the cylindrical fourth pressing member 73. The member 74 presses in the stacking direction DH. As a result, as shown in FIG. 31, the two electrode sheets 40, 40 are placed in the stacking direction DH in the first partial region A1, the second partial region A2, the third partial region A3, and the fourth partial region A4. It is crimped.

As shown in FIG. 31, in the first laminated body 201, among the portions crimped by the press, the portion included in the first partial region A1 becomes the first crimp portion 251 and is included in the second partial region A2. The portion to be crimped becomes the second crimping portion 252, the portion included in the third partial region A3 becomes the third crimping portion 253, and the portion included in the fourth partial region A4 becomes the fourth crimping portion 254. In the first laminated body 201, the first crimping portion 251 and the second crimping portion 252, the third crimping portion 253, and the fourth crimping portion 254 are each two electrode sheets 40 constituting the first laminated body 201. , 40 are connected (connected) in the stacking direction DH.

Next, as shown in FIG. 32, one electrode sheet 40 is laminated on the surface (upper surface) of the first laminated body 201 to which the two electrode sheets 40, 40 are crimped, and the three electrode sheets 40 are laminated. , 40, 40 are laminated in the stacking direction DH to form a second laminated body 202, and the first partial region A1 to the fourth partial region A4 of the second laminated body 202 are pressed by the first pressing members 71 to 4th. The member 74 presses in the stacking direction DH. As a result, as shown in FIG. 33, the three electrode sheets 40, 40, 40 are laminated in the first partial region A1, the second partial region A2, the third partial region A3, and the fourth partial region A4. It is crimped to DH.

As shown in FIG. 33, in the second laminated body 202, among the portions crimped by the press, the portion included in the first partial region A1 becomes the first crimp portion 251 and is included in the second partial region A2. The portion to be crimped becomes the second crimping portion 252, the portion included in the third partial region A3 becomes the third crimping portion 253, and the portion included in the fourth partial region A4 becomes the fourth crimping portion 254. In the second laminated body 202, the first crimping portion 251 and the second crimping portion 252, the third crimping portion 253, and the fourth crimping portion 254 are each three electrode sheets 40 constituting the second laminated body 202. , 40, 40 are connected (connected) in the stacking direction DH.

By crimping the plurality of electrode sheets 40 one by one in this way, the laminate having the first crimping portion 251 and the second crimping portion 252, the third crimping portion 253, and the fourth crimping portion 254. The electrode body 250 is manufactured (see FIG. 34). In the laminated electrode body 250, the first crimping portion 251 and the second crimping portion 252, the third crimping portion 253, and the fourth crimping portion 254 are connected to each other over the entire laminated electrode body 250 in the stacking direction DH. Exists. That is, the first crimping portion 251 and the second crimping portion 252, the third crimping portion 253, and the fourth crimping portion 254 each extend linearly from the front surface 250b to the back surface 250c of the laminated electrode body 250 (columnar column). ).

In the laminated electrode body 250, all the electrode sheets 40 constituting the laminated electrode body 250 are crimped at the portions included in the first crimping portion 251 and the second crimping portion 252, the third crimping portion 253, and the fourth crimping portion 254. Has been done. Specifically, in the electrode sheet 40 constituting the laminated electrode body 250, all the parts included in the first partial region A1 are crimped to the stacking direction DH, and all the parts included in the second partial region A2 are in the stacking direction. It is crimped to the DH, all the portions included in the third partial region A3 are crimped to the stacking direction DH, and all the portions included in the fourth partial region A4 are crimped to the stacking direction DH.

However, in the laminated electrode body 250 having the first crimping portions 251 to the fourth crimping portions 254 as described above, the first crimping portions 251 to the fourth crimping portions 254 may be significantly deformed. Specifically, a part of the electrode sheet 40 constituting the laminated electrode body 250 (a portion included in the first crimping portion 251 to the fourth crimping portion 254, that is, pressed by the first pressing member 71 to the fourth pressing member 74). The portion) was sometimes deformed into a shape that was greatly recessed on the back surface 250c side of the laminated electrode body 250. In particular, a part of the electrode sheet 40 (the portion included in the first crimping portion 251 to the fourth crimping portion 254) located on the surface 250b side of the electrode sheet 40 constituting the laminated electrode body 250 is the laminated electrode body 250. It was sometimes deformed into a shape that was greatly recessed on the back surface 250c side of the above (see FIGS. 34 and 35). Note that FIG. 35 is an enlarged view of the S portion or an enlarged view of the T portion of FIG. 34.

As the number of electrode sheets 40 (the number of layers) is increased in order to make the laminated electrode body 250 a high-capacity laminated electrode body, a part of the electrode sheets 40 is recessed toward the back surface 250c side of the laminated electrode body 250. (Dimensions in the stacking direction DH) tend to be large. Among them, in the electrode sheet 40 located on the most surface 250b side of the laminated electrode body 250, the recess depth D (dimensions in the stacking direction DH of the recesses, see FIG. 35). ) Tended to be particularly large. If the electrode sheet 40 constituting the laminated electrode body 250 is partially deformed in this way, the performance of the battery using the laminated electrode body 250 may be significantly deteriorated.

On the other hand, in the laminated electrode body 50 of the present embodiment, as shown in FIG. 26, the first crimping portion 51 does not exist continuously over the entire laminated electrode body 50 in the stacking direction DH (in other words, in other words. , The first partial region A1 is sandwiched between the electrode sheet 40 which is not crimped (not in a form of being continuous from the front surface 50b to the back surface 50c of the laminated electrode body 50), and exists apart from each other in the stacking direction DH. That is, it is not that "all the electrode sheets 40 constituting the laminated electrode body 50 are crimped at the portion included in the first partial region A1", but among all the electrode sheets 40 constituting the laminated electrode body 50. A part of the electrode sheet 40 is crimped at a portion included in the first partial region A1.

Note that FIG. 26 is a diagram schematically showing the EE cross section or the FF cross section of FIG. In FIG. 26, the cross-sectional shape of the electrode sheet 40 is simplified into a rectangular shape. Further, in FIG. 26, the first crimping portion 51, the second crimping portion 52, the third crimping portion 53, and the fourth crimping portion 54 are shown with cross hatching. That is, in FIG. 26, the portion with cross-hatching is the portion of the electrode sheet 40 that is crimped, and the portion without cross-hatching is the portion of the electrode sheet 40 that is not crimped. be.

More specifically, as shown in FIG. 26, among the electrode sheets 40 constituting the laminated electrode body 50, the electrode sheet 40 in which the first partial region A1 is not crimped (the third electrode sheet from the top in FIG. 26). A plurality of (two) electrode sheets 40 located on the surface 50b side (upper side in FIG. 26) of the laminated electrode body 50 with respect to 40), and an electrode sheet 40 in which the first partial region A1 is not crimped (from the bottom in FIG. 26). A plurality of (two) electrode sheets 40 located on the back surface 50c side (lower side in FIG. 26) of the laminated electrode body 50 with respect to the third electrode sheet 40), or the first partial region A1 is not crimped 2 A plurality of electrode sheets 40 sandwiched between the electrode sheets 40 are pressure-bonded at a portion included in the first partial region A1.

In such a laminated electrode body 50, even if the number of laminated electrodes (total number) of the electrode sheets 40 is the same as that of the conventional laminated electrode body 250, the first partial region A1 is not crimped to the electrode sheet 40. The number of electrode sheets 40 crimped in the first partial region A1 is reduced by the number of sheets. More specifically, the laminated electrode body 50 of the present embodiment has a stacking direction DH in the first partial region A1 even if the number of laminated electrode sheets 40 is the same as that of the conventional laminated electrode body 250. The number of electrode sheets 40 having the first crimping portion connected to (continuously connected to) is reduced.

Here, "the number of electrode sheets 40 having the first crimping portion 51 connected to the stacking direction DH in the first partial region A1 (maximum number of sheets)" is described later in the pressing step (adjacent to the stacking direction DH in the first partial region A1). In the step of crimping the plurality of electrode sheets 40 to be crimped, the first partial region A1 corresponds to the maximum number of electrode sheets 40 to be partially pressed and crimped. Therefore, when the laminated electrode body 50 of the present embodiment is manufactured, the maximum of the electrode sheet 40 in which the first partial region A1 is partially pressed and crimped as compared with the case of manufacturing the conventional laminated electrode body 250. Since the number of sheets is reduced, the amount of deformation (dent depth) of the first partial region A1 (first crimping portion 51) of the electrode sheet 40 can be reduced. In particular, in the first partial region A1 (first crimping portion 51) of the electrode sheet 40 located on the front surface 50b side of the electrode sheets 40 constituting the laminated electrode body 50, the laminated electrode body 50 is deformed to the back surface 50c side. The amount (recess depth D) can be reduced (see FIG. 27). Note that FIG. 27 is an enlarged view of the T portion of FIG. 26.

Further, in the laminated electrode body 50 of the present embodiment, each of the other crimping portions (second crimping portion 52, third crimping portion 53, and fourth crimping portion 54) has the entire laminated electrode body 50 in the stacking direction DH. Each other partial region (second partial region A2, third partial region A3, and so on) without being continuously present over (in other words, not in the form of being continuous from the front surface 50b to the back surface 50c of the laminated electrode body 50). The fourth partial region A4) exists apart from each other in the stacking direction DH with the electrode sheet 40 which is not crimped sandwiched between them.

That is, in each of the other partial regions (second partial region A2, third partial region A3, and fourth partial region A4), "all the electrode sheets 40 constituting the laminated electrode body 50 are in the other partial region (2nd partial region A2, 3rd partial region A3, and 4th partial region A4). It is not "crimped at the sites included in the second partial region A2, the third partial region A3, and the fourth partial region A4)", but a part of all the electrode sheets 40 constituting the laminated electrode body 50. The electrode sheet 40 is crimped at a portion included in other partial regions (second partial region A2, third partial region A3, and fourth partial region A4).

More specifically, as shown in FIG. 26, among the electrode sheets 40 constituting the laminated electrode body 50, a plurality of electrode sheets 40 sandwiched between two electrode sheets 40 in which the second partial region A2 is not crimped ( Each of the three electrode sheets 40) is crimped at a portion included in the second partial region A2. Similarly, among the electrode sheets 40 constituting the laminated electrode body 50, a plurality of (three) electrode sheets 40 sandwiched between two electrode sheets 40 in which the fourth partial region A4 is not crimped are formed. , Each is crimped at a portion included in the fourth partial region A4.

Further, as shown in FIG. 26, among the electrode sheets 40 constituting the laminated electrode body 50, the third partial region A3 is not crimped as compared with the electrode sheet 40 (the third electrode sheet 40 from the top in FIG. 26). A plurality of (two) electrode sheets 40 located on the surface 50b side (upper side in FIG. 26) of the laminated electrode body 50, and an electrode sheet 40 in which the third partial region A3 is not crimped (the third electrode from the bottom in FIG. 26). A plurality of (two) electrode sheets 40 located on the back surface 50c side (lower side in FIG. 26) of the laminated electrode body 50 with respect to the sheet 40), or two electrode sheets in which the third partial region A3 is not crimped. A plurality of electrode sheets 40 sandwiched between the 40s are pressure-bonded at a portion included in the third partial region A3, respectively.

In the laminated electrode body 50 of the present embodiment, the electrode sheet 40 in which the portion included in the first partial region A1 is crimped and the electrode sheet 40 in which the portion included in the third partial region A3 is crimped are formed. ,Match. Further, the electrode sheet 40 in which the portion included in the second partial region A2 is crimped and the electrode sheet 40 in which the portion included in the fourth partial region A4 is crimped are in agreement.

In such a laminated electrode body 50, even if the number of laminated electrodes (total number) of the electrode sheets 40 is the same as that of the conventional laminated electrode body 250, the second partial region A2 (third partial region A3, third part region A3, third The number of electrode sheets 40 crimped in the second partial region A2 (third partial region A3, fourth partial region A4) is reduced by the number of electrode sheets 40 in which the four partial regions A4) are not crimped. More specifically, the laminated electrode body 50 of the present embodiment has a second partial region A2 (third portion) even if the number of laminated electrode sheets 40 is the same as that of the conventional laminated electrode body 250. The number of electrode sheets 40 having the second crimping portion 52 (third crimping portion 53, fourth crimping portion 54) connected to the stacking direction DH in the region A3 and the fourth partial region A4) is reduced.

Here, "an electrode sheet having a second crimping portion 52 (third crimping portion 53, fourth crimping portion 54) connected to the stacking direction DH in the second partial region A2 (third partial region A3, fourth partial region A4). "40 sheets (maximum number of sheets)" is the maximum number of electrode sheets 40 in which the second partial region A2 (third partial region A3, fourth partial region A4) is partially pressed and crimped in the pressing process described later. Matches. Therefore, when the laminated electrode body 50 of the present embodiment is manufactured, the second partial region A2 (third partial region A3, fourth partial region A4) is partially as compared with the case of manufacturing the conventional laminated electrode body 250. Since the maximum number of electrode sheets 40 that are specifically pressed and crimped is reduced, the amount of deformation (dent depth) of the second partial region A2 (third partial region A3, fourth partial region A4) of the electrode sheet 40 is reduced. Can be reduced.

In particular, among the electrode sheets 40 to which the second partial region A2 (third partial region A3, fourth partial region A4) is crimped, the second partial region A2 of the electrode sheet 40 located on the surface 50b side of the laminated electrode body 50 most. In (third partial region A3, fourth partial region A4), the amount of deformation (recess depth D) of the laminated electrode body 50 toward the back surface 50c side can be reduced (see FIGS. 27 and 28). Note that FIG. 28 is an enlarged view of the U portion of FIG. 26. The "electrode sheet 40 located closest to the surface 50b side of the laminated electrode body 50 among the electrode sheets 40 to which the second partial region A2 is crimped" is the second one counting from the surface 50b side of the laminated electrode body 50. The electrode sheet 40. The same applies to the fourth subregion A4. Further, "the electrode sheet 40 located on the surface 50b side of the laminated electrode body 50 most among the electrode sheets 40 to which the third partial region A3 is crimped" is an electrode sheet located on the most surface 50b side of the laminated electrode body 50. It is 40.

As described above, the laminated electrode body 50 of the present embodiment has a first partial region A1 (first crimping portion 51) and a second partial region A2 (second crimping portion) of the electrode sheet 40 constituting the laminated electrode body 50. 52), in the third partial region A3 (third crimping portion 53) and the fourth partial region A4 (fourth crimping portion 54), the amount of deformation (dent depth) of the laminated electrode body 50 toward the back surface 50c side is large. It becomes a reduced laminated electrode body.

Further, in the laminated electrode body 50 of the present embodiment, the electrode sheet 40 in which the second crimping portion 52 and the fourth crimping portion 54 (other crimping portions) are not crimped to the first partial region A1 and the third partial region A3. 2nd partial region A2 and 4th partial region A4 (other partial regions) are included in the present. That is, the electrode sheet 40 that is not crimped in the first partial region A1 and the third partial region A3 with respect to the electrode sheet 40 adjacent to the stacking direction DH is the second partial region A2 and the fourth partial region A4 (other portions). In the region), the electrode sheet 40 adjacent to the stacking direction DH is crimped (see FIG. 26). As a result, the laminated electrode body 50 of the present embodiment is "a laminated electrode body in which the electrode sheets 40 constituting the laminated electrode body 50 are all pressure-bonded to the electrode sheet 40 adjacent to the laminated electrode body DH".

Next, a method of manufacturing the laminated electrode body 50 according to the present embodiment will be described.
First, a plurality of electrode sheets 40 (see FIG. 3) are prepared. In the electrode sheet 40, the positive electrode plate 30, the negative electrode plate 10, and the separators 21 and 22 are laminated and integrated in the stacking direction DH (vertical direction in FIG. 3).

Next, in the pressing step, the plurality of electrode sheets 40 are laminated and pressure-bonded in the stacking direction DH to manufacture the laminated electrode body 50.
Specifically, as shown in FIGS. 6 and 7, first, the first laminated body 101 is formed by laminating the two electrode sheets 40, 40 in the laminating direction DH. Then, in the plan view of the first laminated body 101, among the first partial regions A1 to the fourth partial regions A4 existing at the four corners of the positive electrode mixture layer 33, the first partial region A1 and the third partial region A3 are Press in the stacking direction DH.

Note that FIG. 6 is a plan view of the surface side of the first laminated body 101 in the stacking direction DH in the pressing process. 7 and 8 are views schematically showing the GG cross section or the HH cross section of FIG. In addition, in FIG. 7 and FIG. 8, the cross-sectional shape of the electrode sheet 40 is simplified into a rectangular shape. Further, in FIG. 8, the first crimping portion 51 and the third crimping portion 53 are shown with cross hatching.

In the present embodiment, the pressing process is performed using the pressing device 70. The pressing device 70 includes a columnar first pressing member 71, a columnar second pressing member 72, a columnar third pressing member 73, a columnar fourth pressing member 74, and a flat metal plate. It includes 75,76 and a metal mounting table 78. The first pressing member 71 is arranged at a position (upper in FIG. 7) separated from the surface of the first partial region A1 in the stacking direction DH. The second pressing member 72 is arranged at a position (upper in FIG. 7) separated from the surface of the second partial region A2 in the stacking direction DH. The third pressing member 73 is arranged at a position (upper in FIG. 7) separated from the surface of the third partial region A3 in the stacking direction DH. The fourth pressing member 74 is arranged at a position (upper in FIG. 7) separated from the surface of the fourth partial region A4 in the stacking direction DH. The first pressing member 71 and the third pressing member 73 are configured to move in the stacking direction DH at the same time (synchronically). Further, the second pressing member 72 and the fourth pressing member 74 are configured to move in the stacking direction DH at the same time (synchronically).

Specifically, as shown in FIG. 7, a first laminated body 101 in which two electrode sheets 40, 40 are laminated in the stacking direction DH is placed on the surface (upper surface) of the mounting table 78 of the press device 70. In this state, of the surface (upper surface) of the first laminated body 101, the portion included in the first partial region A1 is pressed by the first pressing member 71 in the stacking direction DH, and the portion included in the third partial region A3. Is pressed in the stacking direction DH by the third pressing member 73. In this press, the parts included in the second partial region A2 and the fourth partial region A4 are not pressed. As a result, as shown in FIG. 8, the two electrode sheets 40, 40 are pressure-bonded to the stacking direction DH in the first partial region A1 and the third partial region A3.

However, in the present embodiment, as shown in FIG. 7, the metal plate 76 is arranged between the two electrode sheets 40, 40 constituting the first laminated body 101. As shown in FIGS. 6 and 7, the metal plate 76 is attached to the electrode sheet 40 located on the back surface side (lower side in FIG. 6) of the two electrode sheets 40, 40 constituting the first laminated body 101. On the other hand, in the length direction BH (left-right direction in FIG. 6), the entire range (second partial region A2 in a plan view) on the side (left side in FIG. 6) where the second partial region A2 and the fourth partial region A4 are located from the center. And the range including the fourth partial region A4).

As shown in FIG. 8, in the first laminated body 101, among the portions crimped by the press, the portion included in the first partial region A1 becomes the first crimp portion 51 and is included in the third partial region A3. The portion becomes the third crimping portion 53. In the first laminated body 101, the first crimping portion 51 and the third crimping portion 53 are connected (connected) in the stacking direction DH over the two electrode sheets 40, 40 constituting the first laminated body 101, respectively. ).

Next, as shown in FIGS. 9 and 10, one electrode sheet 40 is laminated on the surface (upper surface) of the first laminated body 101 to which the two electrode sheets 40, 40 are crimped, and three electrode sheets 40 are laminated. The electrode sheets 40, 40, 40 form a second laminated body 102 in which the electrode sheets 40, 40, 40 are laminated in the stacking direction DH. However, the metal plate 76 remains arranged at the position described above. Then, on the surface (upper surface) of the second laminated body 102, the portion included in the second partial region A2 is pressed by the second pressing member 72 in the stacking direction DH, and the portion included in the fourth partial region A4. Is pressed in the stacking direction DH by the fourth pressing member 74. In this press, the parts included in the first partial region A1 and the third partial region A3 are not pressed.

At this time, the metal plate 76 is arranged between the electrode sheet 40 located on the backmost side (lowermost side in FIG. 10) of the second laminated body 102 and the electrode sheet 40 adjacent thereto. More specifically, with respect to the electrode sheet 40 located on the backmost side (lowermost side in FIG. 10) of the three electrode sheets 40 constituting the second laminated body 102, the length direction BH (in FIG. 10). The metal plate 76 is arranged so as to cover the entire range on the side (left side in FIG. 10) where the second partial region A2 and the fourth partial region A4 are located from the center (in the left-right direction). Therefore, the electrode sheet 40 located on the backmost side (lowermost side in FIG. 10) of the three electrode sheets 40 constituting the second laminated body 102 is located in the second partial region A2 and the fourth partial region A4. At the included portion, the electrode sheet 40 adjacent to the surface side (upper side in FIG. 10) is not crimped.

Therefore, as shown in FIG. 11, in this press, the two electrode sheets 40 located on the surface side (upper side in FIG. 11) of the metal plate 76 are formed in the second partial region A2 and the fourth partial region A4. , Crimped in the stacking direction DH. More specifically, among the three electrode sheets 40 constituting the second laminated body 102, the electrode sheet 40 located on the outermost surface side (uppermost side in FIG. 11) and the back surface side (lower in FIG. 11) thereof. The electrode sheet 40 adjacent to the side) is crimped in the stacking direction DH in the second partial region A2 and the fourth partial region A4.

As shown in FIG. 11, in the second laminated body 102, among the portions crimped by the press, the portion included in the second partial region A2 becomes the second crimp portion 52 and is included in the fourth partial region A4. The portion becomes the fourth crimping portion 54. In the second laminated body 102, the second crimping portion 52 and the fourth crimping portion 54 are located on the front side (upper side in FIG. 11) of the three electrode sheets 40 constituting the second laminated body 102, respectively. The electrode sheets 40 are connected (connected) in the stacking direction DH.

Next, as shown in FIGS. 12 and 13, a metal plate 75 is arranged on the surface (upper surface) of the second laminated body 102 to which the three electrode sheets 40 are crimped, and one electrode sheet 40 is laminated. Then, the four electrode sheets 40 are laminated to form the third laminated body 103 in which the four electrode sheets 40 are laminated in the stacking direction DH. However, the metal plate 76 is left in the position described above. As shown in FIGS. 12 and 13, the metal plate 75 is the electrode sheet 40 located second from the surface (top in FIG. 13) among the four electrode sheets 40 constituting the third laminated body 103. On the other hand, in the length direction BH (horizontal direction in FIG. 13), the entire range (first partial region in a plan view) on the side (right side in FIG. 13) where the first partial region A1 and the third partial region A3 are located from the center. It is arranged so as to cover A1 and the range including the third partial region A3).

Then, as shown in FIG. 13, a portion of the surface (upper surface) of the third laminated body 103 included in the second partial region A2 is pressed by the second pressing member 72 in the stacking direction DH, and the fourth portion is pressed. The portion included in the region A4 is pressed in the stacking direction DH by the fourth pressing member 74. Even in this press, the parts included in the first partial region A1 and the third partial region A3 are not pressed.

At this time, the metal plate 76 is arranged between the electrode sheet 40 located on the backmost side (lowermost side in FIG. 13) of the third laminated body 103 and the electrode sheet 40 adjacent thereto. More specifically, with respect to the electrode sheet 40 located on the backmost side (lowermost side in FIG. 13) of the four electrode sheets 40 constituting the third laminated body 103, the length direction BH (in FIG. 13). The metal plate 76 is arranged so as to cover the entire range on the side (left side in FIG. 13) where the second partial region A2 and the fourth partial region A4 are located from the center (in the left-right direction). Therefore, the electrode sheet 40 located on the backmost side (lowermost side in FIG. 13) of the four electrode sheets 40 constituting the third laminated body 103 is located in the second partial region A2 and the fourth partial region A4. At the included portion, the electrode sheet 40 adjacent to the surface side (upper side in FIG. 13) is not crimped.

Therefore, as shown in FIG. 14, in the present press, in the second partial region A2 and the fourth partial region A4, the most surface side of the four electrode sheets 40 constituting the third laminated body 103 (in FIG. 14). The electrode sheet 40 located on the upper side) is crimped to the electrode sheet 40 adjacent thereto. As a result, of the four electrode sheets 40 constituting the third laminated body 103, the three electrode sheets 40 excluding the electrode sheet 40 located on the backmost side (lowermost side in FIG. 13) are the second. In the partial region A2 and the fourth partial region A4, the pressure is applied in the stacking direction DH.

As shown in FIG. 14, in the third laminated body 103, among the portions crimped by the press, the portion included in the second partial region A2 becomes the second crimp portion 52 and is included in the fourth partial region A4. The portion becomes the fourth crimping portion 54. In the third laminated body 103, the second crimping portion 52 and the fourth crimping portion 54 are located on the backmost side (lowermost side in FIG. 14) of the four electrode sheets 40 constituting the third laminated body 103, respectively. It is connected (connected) in the stacking direction DH over the three electrode sheets 40 excluding the position electrode sheet 40.

Next, as shown in FIGS. 15 and 16, one electrode sheet 40 is laminated on the surface (upper surface) of the third laminated body 103 to which the four electrode sheets 40 are crimped, and the five electrodes are laminated. The sheet 40 forms a fourth laminated body 104 in which the sheets 40 are laminated in the stacking direction DH. However, the metal plate 75 and the metal plate 76 are left arranged at the above-mentioned positions.

Then, as shown in FIG. 16, a portion of the surface (upper surface) of the fourth laminated body 104 included in the first partial region A1 is pressed by the first pressing member 71 in the stacking direction DH, and the third portion is formed. The portion included in the region A3 is pressed by the third pressing member 73 in the stacking direction DH. In this press, the parts included in the second partial region A2 and the fourth partial region A4 are not pressed.

At this time, among the five electrode sheets 40 constituting the fourth laminated body 104, between the electrode sheet 40 located second from the surface (top in FIG. 16) and the electrode sheet 40 located third. A metal plate 75 is arranged. More specifically, among the five electrode sheets 40 constituting the fourth laminated body 104, the electrode sheet 40 located third from the surface (top in FIG. 16) is BH in the length direction (in FIG. 16). (Left and right direction) The entire range on the side (right side in FIG. 16) where the first partial region A1 and the third partial region A3 are located from the center (the range including the first partial region A1 and the third partial region A3 in a plan view). A metal plate 75 is arranged so as to cover the above. Therefore, among the five electrode sheets 40 constituting the fourth laminated body 104, the electrode sheet 40 located third from the surface (upper in FIG. 16) is included in the first partial region A1 and the third partial region A3. At this site, the electrode sheet 40 adjacent to the stacking direction DH is not crimped.

Therefore, as shown in FIG. 17, in the present press, in the first partial region A1 and the third partial region A3, the most surface side of the five electrode sheets 40 constituting the fourth laminated body 104 (in FIG. 17). The electrode sheet 40 located on the upper side) is crimped to the electrode sheet 40 adjacent thereto.

As shown in FIG. 17, in the fourth laminated body 104, among the portions crimped by the press, the portion included in the first partial region A1 becomes the first crimp portion 51 and is included in the third partial region A3. The portion becomes the third crimping portion 53. Therefore, in the fourth laminated body 104, the first crimping portion 51 and the third crimping portion 53 are located on the surface side (upper side in FIG. 17) of the five electrode sheets 40 constituting the fourth laminated body 104. The first crimping portion 51 and the third crimping portion 53 that are connected to the stacking direction DH over the two electrode sheets 40, and the second electrode sheet 40 that is connected to the stacking direction DH over the two electrode sheets 40 located on the back surface side (lower side in FIG. 17). There are 1 crimping portion 51 and 3rd crimping portion 53.

That is, the first crimping portion 51 does not exist continuously over the entire fourth laminated body 104 in the stacking direction DH (in other words, it does not form a continuous structure from the front surface to the back surface of the fourth laminated body 104). One partial region A1 exists apart from each other in the stacking direction DH with an electrode sheet 40 (third electrode sheet 40 from the surface) not crimped in between. Similarly, the third crimping portion 53 does not exist continuously over the entire fourth laminated body 104 in the stacking direction DH (in other words, it does not form a continuous structure from the front surface to the back surface of the fourth laminated body 104). The third partial region A3 exists apart from each other in the stacking direction DH with the electrode sheet 40 (third electrode sheet 40 from the surface) not crimped sandwiched between them.

Next, as shown in FIG. 18, a metal plate 76 is arranged on the surface (upper surface) of the fourth laminated body 104 to which the five electrode sheets 40 are crimped, and one electrode sheet 40 is laminated. , Six electrode sheets 40 form a fifth laminated body 105 in which the six electrode sheets 40 are laminated in the stacking direction DH. However, the metal plate 75 is left in the position described above. On the other hand, unlike the previous time, the metal plate 76 is between the electrode sheet 40 located on the outermost surface side and the electrode sheet 40 adjacent thereto among the six electrode sheets 40 constituting the fifth laminated body 105. Be placed. More specifically, the metal plate 76 is BH in the length direction (FIGS. 15 and 18) with respect to the electrode sheet 40 located second from the surface among the five electrode sheets 40 constituting the fifth laminated body 105. In the left-right direction), the entire range (second partial region A2 and fourth partial region A4 in plan view) of the side (left side in FIGS. 15 and 18) where the second partial region A2 and the fourth partial region A4 are located from the center. It is arranged so as to cover the range including).

Then, as shown in FIG. 18, a portion of the surface (upper surface) of the fifth laminated body 105 included in the first partial region A1 is pressed by the first pressing member 71 in the stacking direction DH, and the third portion is formed. The portion included in the region A3 is pressed by the third pressing member 73 in the stacking direction DH. Even in this press, the parts included in the second partial region A2 and the fourth partial region A4 are not pressed.

At this time, among the six electrode sheets 40 constituting the fifth laminated body 105, between the electrode sheet 40 located third from the surface (top in FIG. 18) and the electrode sheet 40 located fourth. A metal plate 75 is arranged. More specifically, among the six electrode sheets 40 constituting the fifth laminated body 105, the electrode sheet 40 located fourth from the surface (top in FIG. 18) is BH in the length direction (in FIG. 18). (Left and right direction) The entire range on the side (right side in FIG. 18) where the first partial region A1 and the third partial region A3 are located from the center (the range including the first partial region A1 and the third partial region A3 in a plan view). A metal plate 75 is arranged so as to cover the above. Therefore, among the six electrode sheets 40 constituting the fifth laminated body 105, the electrode sheet 40 located fourth from the surface (upper in FIG. 18) is included in the first partial region A1 and the third partial region A3. At this site, the electrode sheet 40 adjacent to the stacking direction DH is not crimped.

Therefore, as shown in FIG. 19, in the present press, in the first partial region A1 and the third partial region A3, the most surface side of the six electrode sheets 40 constituting the fifth laminated body 105 (in FIG. 19). The electrode sheet 40 located on the upper side) is crimped to the electrode sheet 40 adjacent thereto. As a result, in the fifth laminated body 105, the three electrode sheets 40 located on the surface side of the metal plate 75 are pressure-bonded in the first partial region A1 and the third partial region A3 in the stacking direction DH.

As shown in FIG. 19, in the fifth laminated body 105, among the portions crimped by the press, the portion included in the first partial region A1 becomes the first crimp portion 51 and is included in the third partial region A3. The portion becomes the third crimping portion 53. Therefore, in the fifth laminated body 105, the first crimping portion 51 and the third crimping portion 53 are located on the surface side (upper side in FIG. 19) of the six electrode sheets 40 constituting the fifth laminated body 105. The first crimping portion 51 and the third crimping portion 53 connected to the stacking direction DH over the three electrode sheets 40, and the second electrode sheet 40 connected to the stacking direction DH over the two electrode sheets 40 located on the back surface side (lower side in FIG. 19). There are 1 crimping portion 51 and 3rd crimping portion 53.

That is, the first crimping portion 51 does not exist continuously over the entire fifth laminated body 105 in the stacking direction DH (in other words, it is not in a form of being continuous from the front surface to the back surface of the fifth laminated body 105). One partial region A1 exists apart from each other in the stacking direction DH with an electrode sheet 40 (fourth electrode sheet 40 from the surface) not crimped in between. Similarly, the third crimping portion 53 does not exist continuously over the entire fifth laminated body 105 in the stacking direction DH (in other words, it is not in a form of being continuous from the front surface to the back surface of the fifth laminated body 105). The third partial region A3 exists apart from each other in the stacking direction DH with the electrode sheet 40 (fourth electrode sheet 40 from the surface) not crimped sandwiched between them.

Next, as shown in FIG. 20, one electrode sheet 40 is laminated on the surface (upper surface) of the fifth laminated body 105 to which six electrode sheets 40 are crimped, and seven electrode sheets 40 are formed. The sixth laminated body 106 laminated in the stacking direction DH is formed. However, the metal plate 75 and the metal plate 76 are left in the previous positions. Then, as shown in FIG. 20, a portion of the surface (upper surface) of the sixth laminated body 106 included in the second partial region A2 is pressed by the second pressing member 72 in the stacking direction DH, and the fourth portion is pressed. The portion included in the region A4 is pressed in the stacking direction DH by the fourth pressing member 74. In this press, the parts included in the first partial region A1 and the third partial region A3 are not pressed.

At this time, among the seven electrode sheets 40 constituting the sixth laminated body 106, between the electrode sheet 40 located second from the surface (top in FIG. 20) and the electrode sheet 40 located third. A metal plate 76 is arranged. More specifically, among the seven electrode sheets 40 constituting the sixth laminated body 106, the electrode sheet 40 located third from the surface (top in FIG. 20) is BH in the length direction (FIGS. 12 and 12 and). (Left and right direction in FIG. 20) The entire range (second partial region A2 and fourth portion in a plan view) of the side (left side in FIGS. 12 and 20) where the second partial region A2 and the fourth partial region A4 are located with respect to the center. The metal plate 76 is arranged so as to cover the area (range including the area A4).

Therefore, among the seven electrode sheets 40 constituting the sixth laminated body 106, the electrode sheet 40 located third from the surface (upper in FIG. 20) is included in the second partial region A2 and the fourth partial region A4. At this site, the electrode sheet 40 adjacent to the stacking direction DH is not crimped. Further, the electrode sheet 40 located on the backmost side (lowermost side in FIG. 20) is also crimped with the electrode sheet 40 adjacent to the stacking direction DH at the portion included in the second partial region A2 and the fourth partial region A4. Not done.

Therefore, as shown in FIG. 21, in this press, in the second partial region A2 and the fourth partial region A4, the two electrode sheets 40 located on the surface side (upper side in FIG. 21) of the metal plate 76 are formed. , The stacking direction DH is crimped. That is, the electrode sheet 40 located on the most surface side (upper side in FIG. 19) of the seven electrode sheets 40 constituting the sixth laminated body 106 and the electrode sheet 40 adjacent thereto are crimped.

As shown in FIG. 21, of the portions crimped by the press in the sixth laminated body 106, the portion included in the second partial region A2 becomes the second crimped portion 52 and is included in the fourth partial region A4. The portion becomes the fourth crimping portion 54. Therefore, in the sixth laminated body 106, the second crimping portion 52 and the fourth crimping portion 54 are on the surface side of the seven electrode sheets 40 constituting the sixth laminated body 106 with respect to the metal plate 76 (in FIG. 21). The second crimping portion 52 and the fourth crimping portion 54 that are connected to the stacking direction DH over the two electrode sheets 40 located on the upper side) and the stacking direction DH over the three electrode sheets 40 located at the fourth to sixth positions from the surface. There is a second crimping portion 52 and a fourth crimping portion 54 which are connected to the above.

That is, the second crimping portion 52 does not exist continuously over the entire sixth laminated body 106 in the stacking direction DH (in other words, it is not in a form of being continuous from the front surface to the back surface of the sixth laminated body 106). The two partial regions A2 are separated from each other in the stacking direction DH with the electrode sheet 40 (third electrode sheet 40 from the front surface) not crimped, and are also present on the electrode sheet 40 on the backmost side. Not. Similarly, the fourth crimping portion 54 does not exist continuously over the entire sixth laminated body 106 in the stacking direction DH (in other words, it does not extend from the front surface to the back surface of the sixth laminated body 106). The fourth partial region A4 is present apart from the stacking direction DH with the electrode sheet 40 (third electrode sheet 40 from the front surface) not crimped in between, and is also present on the electrode sheet 40 on the backmost side. Not done.

Next, as shown in FIG. 22, the metal plate 75 is arranged on the surface (upper surface) of the sixth laminated body 106 to which the seven electrode sheets 40 are crimped, and one electrode sheet 40 is laminated. , Eight electrode sheets 40 are laminated in the stacking direction DH to form a seventh laminated body 107. However, the metal plate 76 is left in the previous position. On the other hand, unlike the previous time, the metal plate 75 is located between the electrode sheet 40 located on the outermost surface side and the electrode sheet 40 adjacent thereto among the eight electrode sheets 40 constituting the seventh laminated body 107. Be placed. More specifically, the metal plate 75 is BH in the length direction (FIGS. 12 and 22) with respect to the electrode sheet 40 located second from the surface among the eight electrode sheets 40 constituting the seventh laminated body 107. In the left-right direction), the entire range (first partial region A1 and third partial region A3 in a plan view) of the side (right side in FIGS. 12 and 22) where the first partial region A1 and the third partial region A3 are located from the center. It is arranged so as to cover the range including).

Then, as shown in FIG. 22, a portion of the surface (upper surface) of the seventh laminated body 107 included in the second partial region A2 is pressed by the second pressing member 72 in the stacking direction DH, and the fourth portion is formed. The portion included in the region A4 is pressed in the stacking direction DH by the fourth pressing member 74. In this press, the parts included in the first partial region A1 and the third partial region A3 are not pressed.

At this time, among the eight electrode sheets 40 constituting the seventh laminated body 107, between the electrode sheet 40 located third from the surface (top in FIG. 22) and the electrode sheet 40 located fourth. A metal plate 76 is arranged. More specifically, among the eight electrode sheets 40 constituting the seventh laminated body 107, the electrode sheet 40 located fourth from the surface (top in FIG. 22) is BH in the length direction (in FIG. 22). (Left and right direction) The entire range on the side (left side in FIG. 22) where the second partial region A2 and the fourth partial region A4 are located from the center (the range including the second partial region A2 and the fourth partial region A4 in a plan view). A metal plate 76 is arranged so as to cover the above.

Therefore, among the eight electrode sheets 40 constituting the seventh laminated body 107, the electrode sheet 40 located fourth from the surface (upper in FIG. 22) is included in the second partial region A2 and the fourth partial region A4. At this site, the electrode sheet 40 adjacent to the stacking direction DH is not crimped. Further, the electrode sheet 40 located on the backmost side (lowermost side in FIG. 22) is also crimped with the electrode sheet 40 adjacent to the stacking direction DH at the portion included in the second partial region A2 and the fourth partial region A4. Not done.

Therefore, as shown in FIG. 23, in the present press, in the second partial region A2 and the fourth partial region A4, the most surface side of the eight electrode sheets 40 constituting the seventh laminated body 107 (in FIG. 23). The electrode sheet 40 located on the upper side) is crimped to the electrode sheet 40 adjacent thereto. As a result, in the seventh laminated body 107, the three electrode sheets 40 located on the surface side of the metal plate 76 are pressure-bonded to the stacking direction DH in the second partial region A2 and the fourth partial region A4.

As shown in FIG. 23, in the seventh laminated body 107, among the portions crimped by the press, the portion included in the second partial region A2 becomes the second crimp portion 52 and is included in the fourth partial region A4. The portion becomes the fourth crimping portion 54. Therefore, in the 7th laminated body 107, the second crimping portion 52 and the 4th crimping portion 54 are on the surface side of the metal plate 76 among the eight electrode sheets 40 constituting the 7th laminated body 107 (in FIG. 23). The second crimping portion 52 and the fourth crimping portion 54 that are connected to the stacking direction DH over the three electrode sheets 40 located on the upper side) and the stacking direction DH over the three electrode sheets 40 located at the fifth to seventh positions from the surface. There is a second crimping portion 52 and a fourth crimping portion 54 which are connected to the above.

That is, the second crimping portion 52 does not exist continuously over the entire seventh laminated body 107 in the stacking direction DH (in other words, it is not in a form of being continuous from the front surface to the back surface of the seventh laminated body 107). The two partial regions A2 are separated from each other in the stacking direction DH with the electrode sheet 40 (fourth electrode sheet 40 from the front surface) not crimped in between, and are also present on the electrode sheet 40 on the backmost side. Not. Similarly, the fourth crimping portion 54 does not exist continuously over the entire seventh laminated body 107 in the stacking direction DH (in other words, it does not extend from the front surface to the back surface of the seventh laminated body 107). The fourth partial region A4 is present apart from the stacking direction DH with the electrode sheet 40 (fourth electrode sheet 40 from the front surface) not crimped in between, and is also present on the electrode sheet 40 on the backmost side. Not done.

Next, as shown in FIG. 24, one electrode sheet 40 is laminated on the surface (upper surface) of the seventh laminated body 107 to which eight electrode sheets 40 are crimped, and nine electrode sheets 40 are formed. The eighth laminated body 108 laminated in the stacking direction DH is formed. However, the metal plate 75 and the metal plate 76 are left in the previous positions. Then, as shown in FIG. 24, a portion of the surface (upper surface) of the eighth laminated body 108 included in the first partial region A1 is pressed by the first pressing member 71 in the stacking direction DH, and the third portion is formed. The portion included in the region A3 is pressed by the third pressing member 73 in the stacking direction DH. In this press, the parts included in the second partial region A2 and the fourth partial region A4 are not pressed.

At this time, among the nine electrode sheets 40 constituting the eighth laminated body 108, between the electrode sheet 40 located second from the surface (top in FIG. 24) and the electrode sheet 40 located third. A metal plate 75 is arranged. More specifically, among the nine electrode sheets 40 constituting the eighth laminated body 108, the electrode sheet 40 located third from the surface (top in FIG. 24) is BH in the length direction (in FIG. 24). (Left and right direction) The entire range on the side (right side in FIG. 24) where the first partial region A1 and the third partial region A3 are located from the center (the range including the first partial region A1 and the third partial region A3 in a plan view). A metal plate 75 is arranged so as to cover the above.

Therefore, among the nine electrode sheets 40 constituting the eighth laminated body 108, the electrode sheet 40 located third from the surface (top in FIG. 24) is included in the first partial region A1 and the third partial region A3. At this site, the electrode sheet 40 adjacent to the stacking direction DH is not crimped. Further, the electrode sheet 40 located third from the back surface side (lower side in FIG. 24) is also different from the electrode sheet 40 adjacent to the stacking direction DH in the portions included in the first partial region A1 and the third partial region A3. Not crimped.

Therefore, as shown in FIG. 25, in this press, in the first partial region A1 and the third partial region A3, the two electrode sheets 40 located on the surface side (upper side in FIG. 25) of the metal plate 75 are formed. , Crimped in the stacking direction. That is, of the nine electrode sheets 40 constituting the eighth laminated body 108, the electrode sheet 40 located on the outermost surface side (upper side in FIG. 25) and the electrode sheet 40 adjacent thereto are in the first partial region. In A1 and the third partial region A3, the pressure is applied in the stacking direction.

As shown in FIG. 25, in the eighth laminated body 108, among the portions crimped by the press, the portion included in the first partial region A1 becomes the first crimp portion 51 and is included in the third partial region A3. The portion becomes the third crimping portion 53. Therefore, in the eighth laminated body 108, the surface side of the nine electrode sheets 40 constituting the eighth laminated body 108 as the first crimping portion 51 and the third crimping portion 53 is closer to the surface side than the metal plate 75 (in FIG. 25). The first crimping portion 51 and the third crimping portion 53 that are connected to the stacking direction DH over the two electrode sheets 40 located on the upper side) and the stacking direction DH over the three electrode sheets 40 located at the fourth to sixth positions from the surface. The first crimping portion 51 and the third crimping portion 53 connected to the above, and the first crimping portion 51 and the third crimping portion 53 connected to the stacking direction DH over the two electrode sheets 40 located at the first and second positions from the back surface. exist.

That is, the first crimping portion 51 does not exist continuously over the entire eighth laminated body 108 in the stacking direction DH (in other words, it does not form a continuous structure from the front surface to the back surface of the eighth laminated body 108). One partial region A1 exists apart in the stacking direction DH with an electrode sheet 40 (third and seventh electrode sheets 40 from the surface) not crimped sandwiched between them. Similarly, the third crimping portion 53 does not exist continuously over the entire eighth laminated body 108 in the stacking direction DH (in other words, it does not extend from the front surface to the back surface of the eighth laminated body 108). The third partial region A3 is sandwiched between the electrode sheets 40 (third and seventh electrode sheets 40 from the surface) that are not crimped, and are separated from each other in the stacking direction DH.

By crimping the plurality of electrode sheets 40 one by one in this way, as shown in FIG. 26, the first crimping portion 51, the second crimping portion 52, the third crimping portion 53, and the second crimping portion 53. A laminated electrode body 250 having 4 crimping portions 54 is manufactured. In the laminated electrode body 50, as shown in FIG. 26, the first crimping portion 51 does not exist continuously over the entire laminated electrode body 50 in the stacking direction DH (in other words, the surface of the laminated electrode body 50). The first partial region A1 is separated from each other in the stacking direction DH with the electrode sheet 40 which is not crimped in between (not in the form of being continuous from 50b to the back surface 50c). The same applies to the second crimping portion 52, the third crimping portion 53, and the fourth crimping portion 54. The number of electrode sheets 40 constituting the laminated electrode body 50 is not particularly limited, but may be, for example, 65.

In the present embodiment, as can be seen from FIG. 26, the maximum number of electrode sheets 40 having the first crimping portion 51 connected to the stacking direction DH in the first partial region A1 is set to three. In other words, in the present embodiment, the maximum number of electrode sheets 40 for partially pressing and crimping the first partial region A1 by the first pressing member 71 is set to three.

As described above, in the present embodiment, the first partial region A1 is partially pressed even though a large number (for example, 65 sheets) of electrode sheets 40 are laminated and crimped to produce the laminated electrode body 250. The maximum number of electrode sheets 40 to be crimped is reduced to only three. Thereby, in the present embodiment, the amount of deformation (dent depth) of the first partial region A1 (first crimping portion 51) of the electrode sheet 40 constituting the laminated electrode body 50 can be reduced.

In particular, in the present embodiment, as shown in FIG. 27, in the first partial region A1 (first crimping portion 51) of the electrode sheet 40 located on the most surface 50b side of the electrode sheets 40 constituting the laminated electrode body 50. The amount of deformation of the laminated electrode body 50 toward the back surface 50c side (recess depth D) can be made extremely small as compared with the dent depth D (see FIG. 35) of the conventional laminated electrode body 250 (see FIG. 35). ). The same applies to the third partial region A3 (third crimping portion 53).

Further, in the present embodiment, as can be seen from FIG. 26, the number of electrode sheets 40 having the second crimping portion 52 connected to the stacking direction DH in the second partial region A2 is also set to a maximum of three. In other words, in the present embodiment, the maximum number of electrode sheets 40 for partially pressing and crimping the second partial region A2 by the second pressing member 72 is set to three.

As described above, in the present embodiment, the second partial region A2 is partially pressed even though a large number (for example, 65 sheets) of electrode sheets 40 are laminated and crimped to produce the laminated electrode body 250. The maximum number of electrode sheets 40 to be crimped is reduced to only three. Thereby, in the present embodiment, the amount of deformation (dent depth) of the second partial region A2 (second crimping portion 52) of the electrode sheet 40 constituting the laminated electrode body 50 can be reduced.

In particular, in the laminated electrode body 50 of the present embodiment, as shown in FIG. 28, the electrode sheet 40 that is crimped in the second partial region A2 (having the second crimping portion 52) is located on the most surface 50b side. In the second partial region A2 (second crimping portion 52) of the electrode sheet 40 (the second electrode sheet 40 from the surface 50b of the laminated electrode body 50), the amount of deformation (dent depth) of the laminated electrode body 50 toward the back surface 50c side. D) can be made extremely small as compared with the recess depth D (see FIG. 35) of the conventional laminated electrode body 250. The same applies to the fourth partial region A4 (fourth crimping portion 54).

(Evaluation of manufacturing method)
Next, the manufacturing methods according to the embodiment and the comparative embodiment (conventional) were evaluated.
First, in order to evaluate the manufacturing method of the embodiment, the following tests were conducted. Specifically, a flat metal plate is placed on the surface of a laminated body in which 50 electrode sheets 40 are laminated so as to cover the entire surface, and further, three electrodes are placed on the surface of the metal plate. The sheets are laminated to form a laminated body in which a total of 53 electrode sheets 40 are laminated in the laminating direction. Then, a portion of the surface (upper surface) of the laminated body included in the first partial region A1 was pressed by the first pressing member 71 in the stacking direction DH. As a result, the three electrode sheets 40 located 1st to 3rd from the surface of the laminated body were partially pressed in the first partial region A1.

Then, in the first partial region A1 (first crimping portion 51) of the electrode sheet 40 located on the outermost surface side of the laminated body, the amount of deformation (dent depth D) of the laminated body toward the back surface side was measured. In this test, the thickness (dimensions in the stacking direction) of the metal plate interposed between the electrode sheet 40 located at the third position and the electrode sheet 40 located at the fourth position from the surface of the laminated body is increased. , 0.3 mm, 0.5 mm, and 0.7 mm were prepared, and the dent depth D when each metal plate was used was determined. The results are shown in Table 1.

In the above test, although 53 electrode sheets 40 are laminated, between the electrode sheet 40 located third from the surface of the laminated body and the electrode sheet 40 located fourth. The number of electrode sheets 40 for partially pressing the first partial region A1 by sandwiching the metal plate is set to 3 as in the maximum number of the embodiments. Therefore, the above-mentioned test can appropriately evaluate the manufacturing method of the embodiment.

In addition, the following tests were conducted to evaluate the comparative form (conventional) manufacturing method. Specifically, the test was conducted with a difference from the evaluation test of the above-described embodiment only in that a metal plate was not used. That is, 53 electrode sheets 40 are laminated in the stacking direction to form a laminated body, and a portion of the surface (upper surface) of the laminated body included in the first partial region A1 is formed in the stacking direction by the first pressing member 71. Pressed to DH. As a result, 53 electrode sheets 40 were partially pressed in the first partial region A1. The press load by the first pressing member 71 is the same as the evaluation test of the above-described embodiment. Then, in the first partial region A1 (first crimping portion) of the electrode sheet 40 located on the outermost surface side of the laminated body, the amount of deformation (dent depth D) of the laminated body toward the back surface side was measured. The results are shown in Table 1.

As shown in Table 1, in the comparative form (conventional) manufacturing method, the recess depth D of the electrode sheet 40 was 200 μm. On the other hand, in the manufacturing method of the embodiment, the recess depth D of the electrode sheet 40 is 50 μm or 100 μm. Specifically, when a metal plate having a thickness of 0.3 mm was used, the recess depth D of the electrode sheet 40 was 100 μm. Further, when a metal plate having a thickness of 0.5 mm or 0.7 mm was used, the recess depth D of the electrode sheet 40 was 50 μm.

From the above results, according to the manufacturing method of the embodiment, as compared with the manufacturing method of the comparative embodiment (conventional), the laminated electrode body is formed in the first partial region (first crimping portion) of the electrode sheet constituting the laminated electrode body. It can be said that the amount of deformation (dent depth) toward the back surface side can be reduced. Similarly, in the second partial region (second crimping portion), the third partial region (third crimping portion), and the fourth partial region (fourth crimping portion), the amount of deformation of the laminated electrode body toward the back surface side. It can be said that (dent depth) can be reduced. Therefore, the laminated electrode body 50 of the embodiment has a first partial region A1 (first crimping portion 51), a second partial region A2 (second crimping portion 52), and a third portion of the electrode sheet 40 constituting the laminated electrode body 50. In the partial region A3 (third crimping portion 53) and the fourth partial region A4 (fourth crimping portion 54), the laminated electrode in which the amount of deformation (dent depth) of the laminated electrode body 50 toward the back surface 50c side is reduced. It can be said that it is a body.

Although the present invention has been described above in accordance with the embodiment, it goes without saying that the present invention is not limited to the above-described embodiment and can be appropriately modified and applied without departing from the gist thereof.

10 Negative electrode plate 21, 22 Separator 30 Positive electrode plate 40 Electrode sheet 50 Laminated electrode body 51 First crimping part 52 Second crimping part (other crimping part)
53 Third crimping part (other crimping part)
54 4th crimping part (other crimping part)
70 Press device 71 1st pressing member 72 2nd pressing member 73 3rd pressing member 74 4th pressing member 75,76 Metal plate A1 1st partial region A2 2nd partial region (other partial region)
A3 3rd partial area (other partial area)
A4 4th partial area (other partial area)
BH Length direction CH Width direction DH Stacking direction

Claims (1)

In a laminated electrode body in which a plurality of electrode sheets are laminated in the laminating direction, and the plurality of electrode sheets are pressure-bonded in the laminating direction.
Each of the electrode sheets constituting the laminated electrode body is pressure-bonded to the electrode sheet adjacent to the laminated electrode body.
The laminated electrode body is
In the first partial region, which is a partial region of the laminated electrode body in the plane direction orthogonal to the laminating direction, a first crimping portion to which the plurality of electrode sheets adjacent to the laminating direction are crimped, and a first crimping portion.
The plurality of electrode sheets adjacent to the laminated direction were pressure-bonded in one or a plurality of other partial regions of the laminated electrode body which are partial regions in the plane direction and different from the first partial region. With one or more other crimping parts,
The first crimping portion does not exist continuously over the entire laminated electrode body in the laminating direction, and is separated from the laminating direction with the electrode sheet in which the first partial region is not crimped is sandwiched between the first crimping portions. Exists and
Each of the other crimping portions does not exist continuously over the entire laminated electrode body in the laminating direction, and the electrode sheet in which each of the other partial regions is not crimped is sandwiched between the crimping portions. Exists apart in the stacking direction
The other crimping portion of any one of the one or a plurality of other crimping portions is a laminated electrode body in which the first partial region is not crimped and includes the other partial region of the electrode sheet. ..

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