JP6724300B2 - Power storage device - Google Patents

Description

The present invention relates to a power storage device including a plurality of power storage elements.

2. Description of the Related Art Conventionally, there is a power storage device that is used for power storage or power supply and has a plurality of power storage elements. In some of such power storage devices, a plurality of power storage elements are constrained by, for example, a metal member.

Patent Document 1 discloses a battery module including a battery unit in which a plurality of batteries are connected. In this battery module, a pair of end plates are arranged so as to sandwich the battery unit, and a restrictor is fastened to the pair of end plates using bolts and nuts. Patent Document 1 describes that this structure can suppress expansion of the battery unit.

Japanese Patent No. 5336440

In a power storage device including a plurality of power storage elements, when the plurality of power storage elements are constrained in the direction in which the power storage elements are arranged, the end plate and the restraining member (the restrictor in the above-described conventional technique) are fastened with bolts and nuts. Is generally done.

When the end plate and the restraint member are thus connected using the bolt and the nut, the bolt is passed through the through hole provided in the end plate and the restraint member to position the end plate and the restraint member with respect to the other. It can be performed. However, on the other hand, in order to connect the pair of end plates and the restraining member, a plurality of fastening members composed of bolts and nuts are required, and considering the improvement in stability of the connection, the fastening members are The larger number is preferable. This may cause, for example, an increase in the number of parts or weight of the power storage device, resulting in complication of the manufacturing process or structure of the power storage device.

An object of the present invention is to provide a power storage device including a plurality of power storage elements, which can be efficiently manufactured.

In order to achieve the above object, a power storage device according to one embodiment of the present invention is a power storage device including a plurality of power storage elements, and is arranged at one end in a first direction that is a direction in which the plurality of power storage elements are arranged. An end plate and a restraint member that is connected to the end plate and applies a restraining force in the first direction to the plurality of power storage elements, and one of the end plate and the restraint member is in the first direction. A base portion that forms a surface along with, and a protruding portion that is provided so as to protrude from the base portion in a second direction that intersects the first direction, and the other of the end plate and the restraining member is the base portion. And a connection portion welded to at least one of the protrusions.

According to this configuration, since the connection between the end plate and the restraint member is performed by welding, it is not necessary to use another member such as a bolt and a nut or a rivet for the connection. Further, the end plate and the restraint member can be welded together by using, for example, equipment used for welding the electric storage element and the bus bar. Further, during welding, the protrusion can be used for positioning the other of the end plate and the restraining member, so that the accuracy of welding is improved, for example.

Further, since the welding work can be performed from the side in the second direction while pressing the end plate against the plurality of power storage elements in the first direction, the jig holding the end plate may hinder the welding work. Suppressed.

As described above, the power storage device according to this aspect is a power storage device that can be efficiently manufactured.

In the power storage device according to one aspect of the present invention, the connecting portion may be welded to the protruding portion.

According to this configuration, for example, the laser light emitted from the side in the second direction can melt the contact portions of the connection portion and the protruding portion with each other, so that high reliability of the welded portion can be obtained. ..

Further, since the base portion is present at the base of the projecting portion that is the welding partner of the connection portion, for example, another element such as a power storage element located on the opposite side of the welding portion with the base portion interposed therebetween is a laser beam used for welding or Protected from heat etc. by the base.

Further, in the power storage device according to one aspect of the present invention, the connecting portion is a connecting piece portion provided so as to project in the second direction, and at least a part of the connecting piece portion is welded to the protruding portion. You may have.

According to this configuration, it is possible to weld the projecting portion and the connecting piece portion, which are provided so as to project in the same direction, along each other (in a surface contact state). As a result, the welding area becomes relatively large, so that high reliability of the welded portion can be obtained. Further, since the welded portion can be kept away from other elements such as the power storage element on the back side thereof, it is possible to reduce the influence of welding heat or the like on the other elements.

In the power storage device according to the aspect of the present invention, the length of the connecting piece portion in the first direction may be longer than the length of the protruding portion in the first direction.

According to this configuration, the welding operation is performed by combining the end plate and the restraining member in a state where the relative position of the protruding portion in the first direction with respect to the connecting portion is variable (adjustable state). That is, the end plate and the restraint member are connected by welding in a state where the position of the end plate is aligned with the entire length of the plurality of power storage elements to be restrained in the first direction. Therefore, for example, the plurality of power storage devices can be manufactured in a state where the difference in the total length for each combination of the plurality of power storage elements is absorbed.

In the power storage device according to one embodiment of the present invention, the connection portion may have an opening into which the protrusion is inserted.

According to this configuration, since the connecting portion and the base portion or the protruding portion are welded in a state where the protruding portion is inserted into the opening, the stability of the position of the end plate and the restraining member on the other side during welding is stable. Is improved. Thereby, for example, high reliability of the welded portion can be obtained.

In addition, in the power storage device according to one aspect of the present invention, the protruding portion may be provided so as to protrude from the base portion in the second direction because a part of the base portion is formed in a bulge shape. Good.

According to this configuration, the protrusion can be formed by subjecting a part of the metal end plate or the restraint member to a relatively simple process such as drawing. Further, since the protrusion is formed in a box shape or a dome shape, its strength is improved, and as a result, the reliability of the connecting portion between the end plate and the restraining member is improved.

Further, in the power storage device according to the aspect of the present invention, the projecting portion is arranged at an end portion of the end plate in the second direction, and the connecting portion is at an end portion of the restraining member in the first direction. It may be arranged.

According to this configuration, for example, the restraining member can be arranged on the end plate and the welding operation can be performed in a state where the end plate is pressed against the plurality of power storage elements in the first direction. In other words, the arrangement of the restraint member and the welding of the restraint member and the end plate can be continuously performed while the plurality of power storage elements and the end plate are fixed. This is advantageous for efficient manufacturing of the power storage device.

According to the present invention, it is possible to provide a power storage device that includes a plurality of power storage elements and that can be efficiently manufactured.

FIG. 3 is a perspective view showing a schematic configuration of a power storage device according to an embodiment. FIG. 3 is an exploded perspective view showing each component when the power storage unit according to the embodiment is disassembled. FIG. 6 is an exploded perspective view showing a connecting portion between the end plate and the restraint member according to the embodiment. It is a figure which shows an example of the cross-sectional structure of the connection part of the end plate and restraint member which concern on embodiment. It is a side view which shows the relationship of the length in the 1st direction of the connection piece part and protrusion part which concern on embodiment. It is a figure which shows another example of the cross-sectional structure of the connection part of the end plate and connection part which concern on embodiment. FIG. 7 is an exploded perspective view showing a connecting portion between an end plate and a restraint member according to a first modification of the embodiment. FIG. 11 is an exploded perspective view showing a connecting portion between an end plate and a restraint member according to a modified example 2 of the embodiment. FIG. 11 is an exploded perspective view showing a connecting portion between an end plate and a restraining member according to a modified example 3 of the embodiment. FIG. 11 is an exploded perspective view showing a connecting portion between an end plate and a restraint member according to a modified example 4 of the embodiment.

Hereinafter, a power storage device according to an embodiment of the present invention will be described with reference to the drawings. It should be noted that each of the drawings is a diagram for explaining the power storage device according to the embodiment or the modification thereof, and is not necessarily strictly illustrated.

Further, the embodiment described below shows one specific example of the present invention. Numerical values, shapes, materials, constituent elements, arrangement positions and connection forms of constituent elements, assembling methods, assembling orders, and the like shown in the following embodiments are examples, and are not intended to limit the present invention. Further, among the constituent elements according to the following embodiments, the constituent elements that are not described in the independent claims showing the highest concept are described as arbitrary constituent elements.

First, the outline of the configuration of the power storage device 1 will be described with reference to FIGS. 1 and 2. FIG. 1 is a perspective view showing a schematic configuration of a power storage device 1 according to an embodiment. FIG. 2 is an exploded perspective view showing each component when the power storage unit 30 according to the embodiment is disassembled.

In these figures, the Z-axis direction is shown as the vertical direction, and the Z-axis direction will be described below as the vertical direction. However, the Z-axis direction may not be the vertical direction depending on the usage mode. The axial direction is not limited to the vertical direction.

Power storage device 1 is a device capable of charging electricity from the outside and discharging the electricity to the outside. For example, the power storage device 1 is a battery module used for power storage and power supply.

As shown in these drawings, power storage device 1 includes a plurality of power storage elements 100 and an end arranged at one end in a first direction (X-axis direction in the present embodiment) which is a direction in which the plurality of power storage elements 100 are arranged. It has a plate 300 and a restraint member 400. The restraint member 400 is connected to the end plate 300 and applies a restraining force in the first direction to the plurality of power storage elements 100.

In the present embodiment, specifically, power storage device 1 includes eight power storage elements 100, a pair of end plates 300 arranged so as to sandwich eight power storage elements 100 in a first direction, and the pair of end plates 300. And four restraint members 400 for connecting the end plates 300 of FIG. Further, the power storage element 100, the end plate 300, and the restraint member 400 constitute one power storage unit 30, and the power storage unit 30 is housed in the exterior body 10. The outer shape of the outer package 10 is shown by a dotted line in FIG. 1.

The exterior body 10 is a rectangular (box-shaped) container (module case) arranged outside the power storage unit 30. That is, the exterior body 10 is a housing that has the power storage unit 30 arranged at a predetermined position and protects the power storage unit 30 from a shock or the like. The outer package 10 is made of, for example, an insulating resin such as polycarbonate or polypropylene (PP).

The power storage device 1 may include other components such as a positive electrode external terminal and a negative electrode external terminal that are electrically connected to an external device, and an electric device that controls the power storage unit 30. Illustration and description of the constituent elements are omitted.

In the electricity storage unit 30, a spacer 200 is arranged between the adjacent electricity storage elements 100. That is, in the present embodiment, seven spacers 200 are arranged for eight power storage elements 100 arranged in the X-axis direction. The spacer 200 is an insulating resin such as polycarbonate or PP, but may be made of any material as long as it has an insulating property.

By forming the rows of the power storage elements 100 with the spacers 200 interposed between the power storage elements 100 adjacent to each other, the stability of the position of each power storage element 100 at the time of manufacturing or use is improved, for example. This contributes to improvement of the quality or reliability of the power storage device 1, for example.

Further, the plurality of power storage elements 100 are sandwiched and held by the pair of end plates 300 from both sides in the X-axis direction. The end plate 300 is a metal member such as stainless steel or aluminum. An insulating member (not shown in FIG. 2) is arranged between the end plate 300 and the power storage element 100 adjacent to the end plate 300, whereby the end plate 300 and the power storage element 100 are electrically connected. Electrically isolated.

In the present embodiment, the restraint force of the four restraint members 400 is applied to the plurality of power storage elements 100 via the pair of end plates 300. Accordingly, for example, expansion of each power storage element 100 in the thickness direction (X-axis direction in the present embodiment) is suppressed. Further, the strength of the power storage unit 30 as a structure is improved.

In the present embodiment, the end plate 300 projects from the base 310 that forms a surface along the first direction and from the base 310 in the second direction (the Y-axis direction in the present embodiment) that intersects the first direction. And a projecting portion 312 provided as a result. Further, the restraining member 400 has a connecting portion 410 welded to at least one of the base portion 310 and the protruding portion 312. Details of the connecting portion between the end plate 300 and the restraint member 400 will be described later with reference to FIGS.

The power storage element 100 is a secondary battery (single battery) that can charge and discharge electricity, and more specifically, a non-aqueous electrolyte secondary battery such as a lithium ion secondary battery. .. It should be noted that power storage element 100 is not limited to the non-aqueous electrolyte secondary battery, and may be a secondary battery other than the non-aqueous electrolyte secondary battery or a capacitor.

The electricity storage device 100 according to the present embodiment includes a container 110, a positive electrode terminal 103, and a negative electrode terminal 102. Further, an electrode body, a positive electrode current collector, a negative electrode current collector, and the like are arranged inside the container 110.

The container 110 is composed of a main body having a rectangular tubular shape made of metal and having a bottom, and a metallic lid portion that closes an opening of the main body. The container 110 has a structure for sealing the inside by accommodating the electrode body and the like inside and then welding the lid and the main body together.

There is no particular limitation on the type of electrode body included in the electricity storage device 100, but for example, a wound electrode formed by winding a layered structure in which a separator is sandwiched between a positive electrode and a negative electrode. The body is contained in the container 110.

The positive electrode terminal 103 is an electrode terminal electrically connected to the positive electrode of the electrode body via the positive electrode current collector, and the negative electrode terminal 102 is electrically connected to the negative electrode of the electrode body via the negative electrode current collector. It is the connected electrode terminal.

That is, the positive electrode terminal 103 and the negative electrode terminal 102 lead out the electricity stored in the electrode body to the external space of the power storage element 100, and introduce the electricity into the internal space of the power storage element 100 to store the electricity in the electrode body. It is an electrode terminal made of metal for performing.

The plurality of power storage elements 100 in the power storage unit 30 are connected in series or in parallel via the positive electrode terminal 103 and the negative electrode terminal 102. The mode of electrical connection of the plurality of power storage elements 100 is not particularly limited, but for example, by connecting electrode terminals adjacent to each other in the X-axis direction by a conductive member (not shown) such as a bus bar, Power storage devices 100 are connected in series/parallel (2 parallel×4 series).

Note that in this embodiment, the positive electrode terminal 103 and the negative electrode terminal 102 are both formed with flat upper surfaces, and a conductive member such as a bus bar is joined to the positive electrode terminal 103 and the negative electrode terminal 102 by welding (for example, laser welding). To be done.

Next, the structure of the connecting portion between the end plate 300 and the restraint member 400 and the structure around it will be described with reference to FIGS. 3 to 6.

FIG. 3 is an exploded perspective view showing a connecting portion between the end plate 300 and the restraining member 400 according to the embodiment. Note that, in FIG. 3, the end plate 300 and the restraint member 400 are shown separately and enlarged in order to make it easy to understand the characteristics of the connecting portion between the end plate 300 and the restraint member 400 according to the embodiment.

FIG. 4 is a diagram showing an example of a cross-sectional configuration of a connecting portion between the end plate 300 and the restraining member 400 according to the embodiment. In addition, in FIG. 4, the cross section when the end plate 300 and the connection portion 410 in a state where the protrusion 312 is inserted into the opening 412 of the connection portion 410 is cut along the XZ plane passing through the center of the protrusion 312 in the X-axis direction. Are shown. This also applies to FIG. 6 described later.

Further, in the following, the connection portion 410 provided at one end portion (the end portion on the minus side in the X-axis direction) of the one restraining member 400 in the longitudinal direction and the connection portion between the end plate 300 are focused and described. I do. The structural features described below may be commonly applied to all of the connecting portions (total of 8 places) between the two end plates 300 and the four restraining members 400 in the present embodiment, and It may be applied only to some connection parts.

As shown in FIGS. 3 and 4, in the present embodiment, end plate 300 has base portion 310 that forms a surface along the first direction (X-axis direction) that is the direction in which the plurality of power storage elements 100 are arranged. .. The base portion 310 is provided with a protrusion 312 that protrudes in a second direction (Y-axis direction) that intersects the first direction.

The restraint member 400 is mechanically connected to the end plate 300 by welding the connection portion 410 to the end plate 300. In the present embodiment, as shown in FIG. 4, the connecting portion 410 is welded to the protruding portion 312. In addition, W1 in FIG. 4 represents an approximate region where the connecting portion 410 and the protruding portion 312 are welded.

More specifically, the connecting portion 410 has the connecting piece portion 411 provided so as to project in the second direction (Y-axis direction), and at least a part of the connecting piece portion 411 is welded to the protruding portion 312.

Thus, in power storage device 1 according to the present embodiment, welding is used to connect end plate 300 and restraint member 400. Therefore, it is not necessary to use other members such as bolts and nuts or rivets for the connection, and as a result, an increase in the number of parts required for manufacturing the power storage device 1 is suppressed. In addition, the end plate 300 and the restraint member 400 can be welded by using, for example, equipment (for example, a laser welding machine) used for welding the power storage device 100 and the bus bar or the like. In addition, during welding, the protrusion 312 can be used for positioning the end plate 300 and the restraining member 400 with respect to the other, so that, for example, welding accuracy is improved.

Here, when a fastening member (for example, a bolt and a nut) that is a solid metal body is used to connect the end plate and the restraining member included in the power storage device, the fastening is performed when a severe impact is applied to the power storage device. It is possible that the member damages the power storage element in the power storage device. In that respect, since the power storage device 1 according to the present embodiment does not use such a fastening member for connecting the end plate 300 and the restraint member 400, the power storage device when the power storage device 1 is subjected to a severe impact. The likelihood of damage to components such as 100 is reduced.

Further, according to the power storage device 1 of the present embodiment, when manufacturing the end plate 300, the welding work can be performed from the side in the Y-axis direction while pressing the end plate 300 in the X-axis direction. It is possible to prevent the jig that holds 300 from hindering the welding operation. That is, the end plate 300 and the restraint member 400 that restrain the plurality of power storage elements 100 in the arrangement direction (first direction (X-axis direction)) can be efficiently attached to the plurality of power storage elements 100.

As described above, power storage device 1 according to the present embodiment is a power storage device that can be manufactured efficiently.

Further, in the present embodiment, since the connecting portion 410 and the protruding portion 312 are welded together, for example, the connecting portion 410 and the protruding portion 312 are in contact with each other by laser light emitted from the side in the Y-axis direction. Can be melted together. Thereby, high reliability of the welded portion can be obtained. Further, the base portion 310 existing at the base of the protruding portion 312 can protect other elements such as the power storage element 100 from the laser light used for welding, the heat of welding, and the like.

Further, in the present embodiment, as shown in FIG. 4, the projecting portion 312 and the connecting piece portion 411, which are provided so as to project in the same direction, are welded to each other (surface contact state). As a result, the welding area becomes relatively large. That is, the amount of each of the end plate 300 and the restraint member 400 melted together becomes relatively large. Therefore, high reliability of the welded portion can be obtained. Further, since the welded portion (W1 in FIG. 4) can be kept away from other elements such as the storage element 100 on the back side thereof, it is possible to reduce the influence of welding heat or the like on the other elements.

Here, in the present embodiment, as shown in FIG. 4, the protruding portion 312 and the connecting piece portion 411 are formed at the base portion of the protruding portion 312 so that a space S is formed between the protruding portion 312 and the connecting piece portion 411. Are placed. Since the air layer contained in the void S functions as a heat insulating layer for heat of welding, it is possible to further reduce the influence of the heat on the other elements.

Further, the connecting portion 410 has an opening 412 into which the protruding portion 312 is inserted, as shown in FIGS. 3 and 4, for example. That is, since the connecting portion 410 and the protruding portion 312 are welded in the state where the protruding portion 312 is inserted into the opening 412, the stability of the position of the other end relative to one of the end plate 300 and the restraint member 400 during welding is improved. Be improved. Thereby, for example, high reliability of the welded portion can be obtained.

Further, as shown in, for example, FIGS. 3 and 4, the protruding portion 312 is provided so as to protrude from the base portion 310 in the Y-axis direction because a part of the base portion 310 is formed in a bulge shape. That is, the protrusion 312 can be provided on the end plate 300 by performing a relatively simple process such as drawing on a part of the metal end plate 300. Further, in this case, since the protruding portion 312 is formed in a box shape (or a dome shape), its strength is improved, and as a result, the reliability of the connection portion between the end plate 300 and the restraining member 400 is improved.

Further, in the present embodiment, the protruding portion 312 is arranged at the end of the end plate 300 in the Y-axis direction, and the connecting portion 410 is arranged at the end of the restraint member 400 in the X-axis direction. Thereby, for example, in a state where the end plate 300 is pressed against the plurality of power storage elements 100 in the X-axis direction, the restraining member 400 can be arranged on the end plate 300 to perform welding work. That is, with the plurality of power storage devices 100 and the end plates 300 fixed, the constraining member 400 can be arranged and the constraining member 400 and the end plate 300 can be continuously welded. This is advantageous for efficient manufacturing of power storage device 1.

Here, since the end plate 300 has a role of directly giving the restraining force of the restraining member 400 to the plurality of power storage elements 100, the restraining member is pressed against the plurality of power storage elements 100 with a predetermined pressure. It is preferably welded to 400. In addition, the total number of thicknesses of the predetermined number (8 in the present embodiment) of power storage elements 100 may change for each combination of power storage elements 100 due to individual differences in power storage elements 100.

Therefore, in the present embodiment, the shapes and sizes of the protruding portion 312 and the connecting portion 410 are determined so that the position of the end plate 300 with respect to the connecting portion 410 of the restraining member 400 is variable.

FIG. 5 is a side view showing the relationship between the lengths of the connecting piece portion 411 and the protruding portion 312 in the first direction according to the embodiment.

As shown in FIG. 5, in the present embodiment, the length L1 of the connecting piece portion 411 of the connecting portion 410 in the first direction (X-axis direction) is the same as the length L1 of the protruding portion 312 in the first direction (X-axis direction). It is longer than the length L2.

That is, when welding the protruding portion 312 and the connecting piece portion 411, the protruding portion 312 can move in the X-axis direction with respect to the connecting piece portion 411 in a state of having a contact area with the connecting piece portion 411. is there. Further, at this time, since the protruding portion 312 is in the state of being inserted into the opening 412 of the connecting portion 410, the movement in the Z-axis direction is restricted. That is, the position of the protruding portion 312 in the Z-axis direction is in a state of being positioned.

In this state, a predetermined pressing force is applied to the end plate 300 in the direction of the plurality of power storage elements 100 (X axis direction plus side), whereby the position of the end plate 300 in the X axis direction is determined. Further, while maintaining this state, by welding the protruding portion 312 and the connection portion 410, the plurality of power storage elements 100 are connected to each other in a state in which a constraint force in the X-axis direction is applied to the plurality of power storage elements 100. It can be fixed as one group. Note that, for example, before the welding is performed, the connection portion 410 at the other end portion (end portion on the X axis direction positive side) of the restraining member 400 and the right side of the plurality of power storage elements 100 (X axis direction plus side). Welding with the end plate 300 is completed.

As described above, in the present embodiment, the length L1 of the connecting piece portion 411 in the X-axis direction is longer than the length L2 of the protruding portion 312 in the X-axis direction. Therefore, at least one of the pair of end plates 300 and the restraint member 400 are welded in a state where the distance between the pair of end plates 300 is adjusted to the entire length of the plurality of power storage elements 100 to be restrained in the X-axis direction. Can be connected by. Therefore, for example, the plurality of power storage devices 1 can be manufactured in a state where the difference in the total length for each combination of the plurality of power storage elements 100 is absorbed.

In addition, in the present embodiment, the connection between the end plate 300 and the connection portion 410 is performed by welding the protruding portion 312 of the end plate 300 and the connection piece portion 411 of the connection portion 410, but they are welded. The part is not limited to these.

FIG. 6 is a diagram showing another example of the cross-sectional configuration of the connecting portion between the end plate 300 and the connecting portion 410 according to the embodiment.

For example, as shown in FIG. 6, the base portion 310 of the end plate 300 and the flat surface portion of the connection portion 410 (the portion outside the connection piece portion 411 that forms the surface along the X-axis direction) may be welded. .. Note that W2 in FIG. 6 represents an approximate region where the base portion 310 and the connection portion 410 are welded.

In this case, the degree of freedom of the range and position of welding is relatively high in a side view (when viewed from the Y-axis direction plus side). The fixing force for the plate 300 can be improved.

Further, in this case, the protruding portion 312 does not directly participate in welding, but functions as a portion for positioning the connecting portion 410 with respect to the end plate 300.

Further, the connection part 410 may be welded to both the base part 310 and the protrusion part 312. For example, the end plate 300 and the restraint member 400 may be connected by welding both regions of W1 shown in FIG. 4 and W2 shown in FIG. Thereby, the end plate 300 and the restraint member 400 are more firmly connected.

The connection portion between the end plate 300 and the restraining member 400 included in the power storage device 1 may have a structure different from the structures shown in FIGS. 3 to 6. Therefore, a modified example regarding the connecting portion between the end plate 300 and the restraining member 400 will be described below, focusing on the difference from the above-described embodiment.

(Modification 1)
FIG. 7 is an exploded perspective view showing a connecting portion between the end plate 300 and the restraining member 400 according to the first modification of the embodiment. Note that, in FIG. 7, the end plate 300 and the restraint member 400 are shown separately and enlarged in order to make it easy to understand the characteristics of the connecting portion between the end plate 300 and the restraint member 400 according to the present modification. Illustration of elements other than is omitted. This also applies to FIGS. 8 to 10 described later.

In the power storage device 1a according to the present modification, the end plate 300 and the restraining member 400 are welded together with the projecting portion 312 of the end plate 300 inserted in the opening 422 of the connecting portion 420 of the restraining member 400. .. Therefore, fastening members such as bolts and nuts are not necessary for connecting the end plate 300 and the restraining member 400. These points are common to the power storage device 1 according to the above-described embodiment. However, in power storage device 1a according to the present modification, connecting portion 420 does not have a connecting piece portion, and this is different from the above embodiment.

In this case, for example, welding (welding between the connecting piece portion 411 and the protruding portion 312) in the mode shown in FIG. 4 cannot be performed. However, welding can be performed between the connecting portion 420 and the base portion 310 of the end plate 300 in a state in which the position of the end plate 300 with respect to the connecting portion 420 (restraining member 400) is restricted by the protruding portion 312 (for example, in the drawings. 6). Further, for example, the peripheral edge of the opening 422 of the connection portion 420 and the root portion of the protrusion 312 can be welded. In any case, the welding work can be performed from the side in the Y-axis direction while pressing the end plate 300 against the plurality of power storage elements 100 in the X-axis direction.

Therefore, the power storage device 1a according to the present modification is a power storage device that can be efficiently manufactured.

(Modification 2)
FIG. 8 is an exploded perspective view showing a connecting portion between the end plate 300 and the restraint member 400 according to the second modification of the embodiment.

In the power storage device 1b according to the present modification, the end plate 300 and the restraining member 400 are welded together with the projecting portion 322 of the end plate 300 inserted in the opening 412 of the connecting portion 410 of the restraining member 400. Therefore, fastening members such as bolts and nuts are not necessary for connecting the end plate 300 and the restraining member 400. These points are common to the power storage device 1 according to the above-described embodiment. However, in the power storage device 1b according to the present modification, the protruding portion 322 is formed by cutting and raising a part of the base portion 310, which is different from the above embodiment.

Even in this case, for example, the connection piece 411 and the protrusion 322 can be welded. That is, the regions (regions corresponding to W1 in FIG. 4) at the end portions of the connecting piece portion 411 and the protruding portion 322 can be welded. Therefore, for example, the influence of welding heat or the like on other elements such as the power storage element 100 can be reduced. Further, welding work can be performed from the side in the Y-axis direction while pressing the end plate 300 against the plurality of power storage elements 100 in the X-axis direction.

Therefore, the power storage device 1b according to the present modification is a power storage device that can be efficiently manufactured.

(Modification 3)
FIG. 9 is an exploded perspective view showing a connecting portion between the end plate 300 and the restraint member 400 according to the modified example 3 of the embodiment.

In the power storage device 1c according to the present modification, the end plate 300 and the restraint member 400 are welded together with the protrusion 432 inserted in the opening 332 of the connection portion 330. Therefore, fastening members such as bolts and nuts are not necessary for connecting the end plate 300 and the restraining member 400. The connecting portion 330 has a connecting piece portion 331, and the end plate 300 and the restraining member 400 can be connected by welding the connecting piece portion 331 and the protruding portion 432. These points are common to the power storage device 1 according to the above-described embodiment. However, in the power storage device 1c according to the present modification, the end plate 300 has the connecting portion 330, and the restraining member 400 has the base portion 431 and the projecting portion 432. Is different from.

Even in this case, for example, since the connecting piece 331 and the protruding portion 432 can be welded, the welding can be performed at a position relatively far from other elements such as the power storage element 100. Further, since the projecting portion 432 is inserted into the opening 332 of the connecting portion 330, welding of the connecting portion 330 and the projecting portion 432 of the restraining member 400 is performed while the position of the end plate 300 with respect to the restraining member 400 is restricted. It can be carried out. Furthermore, welding work can be performed from the side in the Y-axis direction while pressing the end plate 300 against the plurality of power storage elements 100 in the X-axis direction.

Therefore, the power storage device 1c according to the present modification is a power storage device that can be efficiently manufactured.

As described above, the base portion that forms the surface along the first direction and the protruding portion that is provided so as to protrude from the base portion in the second direction that intersects the first direction are one of the end plate 300 and the restraining member 400. There should be. In this case, the other of the end plate 300 and the restraint member 400 may have a connection portion welded to at least one of the base portion and the protruding portion.

(Modification 4)
FIG. 10 is an exploded perspective view showing a connecting portion between the end plate 300 and the restraining member 400 according to the modified example 4 of the embodiment.

In the power storage device 1d according to the present modification, the protrusion 312 or the base 310 of the end plate 300 is welded to the connecting portion 440 of the restraint member 400, so that the end plate 300 and the restraint member 400 are connected. Therefore, fastening members such as bolts and nuts are not necessary for connecting the end plate 300 and the restraining member 400. These points are common to the power storage device 1 according to the above-described embodiment. However, in the power storage device 1d according to the present modification, the connecting portion 440 does not have an opening, and this point is different from the above embodiment.

In the present modification, the connection piece portion 441 of the connection portion 440 is arranged along the upper surface (the surface on the Z axis direction plus side) of the protruding portion 312 of the end plate 300, and in that state, for example, the connection piece portion The 441 and the protrusion 312 are welded. Accordingly, the connection portion 330 and the protruding portion 432 of the restraint member 400 can be welded while the position of the end plate 300 with respect to the restraint member 400 in the Z-axis direction is regulated.

Further, at this time, by welding the regions (regions corresponding to W1 in FIG. 4) at the end portions of the connecting piece portion 441 and the protruding portion 312, for example, heat of welding or the like is given to other elements such as the power storage element 100. The influence can be reduced.

Further, welding work can be performed from the side in the Y-axis direction while pressing the end plate 300 against the plurality of power storage elements 100 in the X-axis direction.

Therefore, the power storage device 1d according to the present modification is a power storage device that can be efficiently manufactured.

The connecting portion 440 may not have the connecting piece portion 441. In this case, for example, the end plate 300 and the restraint member 400 are connected to each other by welding the portion of the connecting portion 440 that forms the surface along the X-axis direction and the base portion 310 of the end plate 300. Further, when performing this welding, by performing the connection portion 440 along the protruding portion 312, the welding is performed while regulating the position of the connection portion 440 (restraining member 400) in the Z-axis direction with respect to the end plate 300. You can

(Other embodiments)
The power storage device according to the present invention has been described above based on the embodiment and its modifications. However, the present invention is not limited to the above embodiment and its modifications. Without departing from the spirit of the present invention, various modifications that a person skilled in the art can think of may be applied to the above-described embodiment or its modifications, or an embodiment constructed by combining a plurality of the above-described components. Included within the scope of the invention.

For example, the opening 412 included in the connecting portion 410 according to the above-described embodiment is provided along the X-axis direction from the end surface of the connecting portion 410 (restraining member 400) on the minus side in the X-axis direction as shown in FIG. 5, for example. The restraint member 400 is provided with the groove. However, the opening 412 does not have to be a groove extending from the end surface, and the opening 412 may be provided as a through hole formed in the connecting portion 410, for example.

Even in this case, by inserting the protrusion 312 into the opening 412, positioning of the end plate 300 with respect to the restraining member 400 at the time of welding the end plate 300 and the restraining member 400 is facilitated. If the length of the through hole that is the opening 412 in the X axis direction is longer than the length of the protrusion 312 in the X axis direction, the relative position of the end plate 300 in the X axis direction with respect to the connecting portion 410 during welding. Can be adjusted.

Further, the number and position of the restraint members 400 are not limited to the number and position shown in the above embodiment. For example, one or more restraint members 400 extending in the X-axis direction may be arranged below the plurality of power storage elements 100 (negative side in the Z-axis direction).

In this case, at the lower end of the end plate 300, a base 310 that forms a surface along the first direction (X-axis direction), and a protrusion that protrudes from the base 310 in a second direction (Z-axis direction) intersecting the first direction. And section 312. Further, similarly, one or more restraint members 400 extending in the X-axis direction may be arranged on the upper side (the positive side in the Z-axis direction) of the plurality of power storage elements 100. In either case, fastening members such as bolts and nuts are not required to connect the end plate 300 and the restraining member 400. In addition, welding work can be performed from the side in the Y-axis direction or the Z-axis direction while pressing the end plate 300 against the plurality of power storage elements 100 in the X-axis direction.

Further, the welding of the protruding portion 312 and the connecting piece portion 411 may be performed by laser light emitted from the side in the Z-axis direction instead of the side in the Y-axis direction. For example, the projection 312 and the connection piece 411 may be welded by irradiating the connection piece 411 with laser light from above (on the Z axis direction positive side) in FIG. In this case, the projecting portion 312 and the connecting piece portion 411 can be welded without directing the laser light to other elements such as the power storage element 100 and the spacer 200. Therefore, the influence of laser light on these other elements can be further reduced.

When irradiating the laser light from the side in the Z-axis direction, the same laser welding machine is used while maintaining the posture of the plurality of power storage elements 100 with respect to the laser welding machine, and electrode terminals (102) of the plurality of power storage elements 100 are used. Alternatively, it is also possible to perform the welding work between 103) and the bus bar or the like, and the welding work between the protruding portion 312 and the connecting piece portion 411. This is because the direction of laser light can be unified in the Z-axis direction.

The welding of the end plate 300 and the restraint member 400 is not limited to laser welding. For example, the end plate 300 and the restraint member 400 may be connected by a different type of welding from laser welding, such as resistance welding or electron beam welding.

Further, the number of restraint members welded to one protrusion 312 or the base 310 around the protrusion 312 may be two or more. For example, two restraining members that are long in the X-axis direction are arranged side by side in the Z-axis direction such that each connecting portion sandwiches one protrusion 312 from both sides in the Z-axis direction. Further, the connecting portion of each restraint member is welded to the protruding portion 312 or the base portion 310. In this case, the connecting portions of the two restraint members are positioned at least in the Z-axis direction by the protrusions 312, so that the welding accuracy of the connecting portions of the respective restraint members and the protrusions 312 or the base portion 310 is improved. ..

Further, in this case, the connecting portion of the two restraint members may have a connecting piece portion formed on the side of the protruding portion 312, such as the connecting piece portion 441 according to the fourth modification. As a result, it is possible to obtain the effect of improving the reliability of the welded portion or reducing the influence of the heat of welding on other elements such as the power storage element 100.

Further, the number of end plates 300 to be welded by adjusting the position of the restraint member 400 may be one. For example, it is assumed that one or more restraint members 400 and a plate-like member forming a surface orthogonal to the longitudinal direction of the one or more restraint members 400 are integrally molded. In this case, one end plate 300 and the one or more restraint members 400 are connected by welding while the plurality of power storage elements 100 are sandwiched between the one end plate 300 and the plate member. Also by doing so, the power storage unit 30 included in the power storage device 1 can be configured.

In other words, one of the pair of end plates 300 holding the plurality of power storage elements 100 may be integrally formed with the one or more restraint members 400.

The present invention can be applied to a power storage device or the like including a plurality of power storage elements.

1, 1a, 1b, 1c, 1d Storage device 10 Exterior body 30 Storage unit 100 Storage element 102 Negative electrode terminal 103 Positive electrode terminal 110 Container 200 Spacer 300 End plate 310, 431 Base part 312, 322, 432 Projection part 330, 410, 420, 440 connection part 331, 411, 441 connection piece part 332, 412, 422 opening 400 restraint member

Claims (7)

A power storage device comprising a plurality of power storage elements,
An end plate arranged at one end in the first direction, which is the direction in which the plurality of power storage elements are arranged,
A restraint member that is connected to the end plate and applies a restraint force in the first direction to the plurality of power storage elements;
One of the end plate and the restraint member has a base portion that forms a surface along the first direction, and a protrusion portion that protrudes from the base portion in a second direction intersecting the first direction. Then
The other of the end plate and the restraint member has a connection portion welded to at least one of the base portion and the protrusion,
The power storage device, wherein the connection portion has a connection piece portion that is provided so as to project in the second direction and at least a portion of which is welded to the projection portion. The power storage device according to claim 1, wherein a length of the connection piece in the first direction is longer than a length of the protrusion in the first direction. The power storage device according to claim 1, wherein the connection portion has an opening into which the protrusion is inserted. The electricity storage according to any one of claims 1 to 3, wherein the protruding portion is provided so as to protrude from the base portion in the second direction by forming a part of the base portion in a bulge shape. apparatus. The protrusion is arranged at an end of the end plate in the second direction,
The power storage device according to claim 1, wherein the connecting portion is arranged at an end portion of the restraining member in the first direction. A power storage device comprising a plurality of power storage elements,
A pair of end plates formed of end plates arranged at both ends of the first direction, which is the direction in which the plurality of power storage elements are arranged,
A restraint member that is connected to the pair of end plates and applies a restraining force in the first direction to the plurality of power storage elements;
One of the pair of end plates and the restraint member includes a base portion that forms a surface along the first direction, and a protrusion portion that is provided so as to protrude from the base portion in a second direction that intersects the first direction. Has a connected part consisting of
The other of the pair of end plates and the restraining member has a connecting portion welded to at least one of the base portion and the protruding portion,
The restraint member is provided with one of the connected portion and the connecting portion at both ends in the first direction,
Each of the pair of end plates is provided with the other of the connected portion and the connecting portion, which is welded to the one of the connected portion and the connecting portion provided on the restraining member ,
The connection portion is a connection piece portion provided so as to project in the second direction, at least one of a connection piece portion at least a part of which is welded to the projection portion, and an opening into which the projection portion is inserted. Power storage device having a . A power storage device comprising a plurality of power storage elements,
An end plate arranged at one end in the first direction, which is the direction in which the plurality of power storage elements are arranged,
A restraint member that is connected to the end plate and applies a restraint force in the first direction to the plurality of power storage elements;
One of the end plate and the restraint member has a base portion that forms a surface along the first direction, and a protrusion portion that protrudes from the base portion in a second direction intersecting the first direction. Then
The other of the end plate and the restraint member has a connection portion welded to at least one of the base portion and the protrusion,
The connection portion is formed in a shape that is movable within a predetermined range in the first direction with respect to at least one of the base portion and the projection portion that are welding partners in an unwelded state, and Welded in any position within the specified range ,
The connection portion is a connection piece portion provided so as to project in the second direction, at least one of a connection piece portion at least a part of which is welded to the projection portion, and an opening into which the projection portion is inserted. Power storage device having a .

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