JP2021144907A - Solid power storage device and method for manufacturing the same - Google Patents

Abstract

To provide a solid power storage device capable of sufficiently ensuring the airtightness of an all-solid-state battery laminate by a resin layer with a simple configuration, and a method for manufacturing the same.SOLUTION: A solid power storage device has a solid battery laminate 1 in which positive electrode systems 30 and negative electrode systems 10 are alternately laminated, and the projected shape of the solid power storage device in the lamination direction is approximately square. The positive electrode systems and the negative electrode systems are provided with a sealing frame 17 which is surrounded by four sealing members 13, 14, 15, and 16 extending along the sides of the outer circumference of the square to seal the inside. The sealing frame has a three-way sealing member 18 in which the sealing members 13, 14 and 15 on the three sides of the outer circumference are connected to one another, and a closing sealing member 19 for closing the open side. At least one of the three-way sealing member 18 and the closing sealing member 19 is provided with a stepped portion 153 formed at the contact portion therebetween.SELECTED DRAWING: Figure 6

Description

The present invention relates to a solid-state power storage device and a method for manufacturing the same.

A solid power storage device has been proposed in which a solid electrolyte is arranged at the interface connecting the positive electrode system and the negative electrode system, and ions of the positive electrode system and the negative electrode system are transferred via this solid electrolyte during charging and discharging (for example). , Patent Document 1).

On the other hand, in a solid-state power storage device in which the side surface of the all-solid-state battery laminate is covered with a resin layer, a technique for improving the adhesiveness between the all-solid-state battery laminate and the resin layer has been proposed (for example, Patent Document 2). reference). In the proposal in Patent Document 2, at least one surface of at least one of the positive electrode current collector layer and the negative electrode current collector layer extends from the laminated portion as a portion overlapping with the adjacent other layer and the other layer. An extension section is provided. The surface roughness of the extended portion is roughened to ensure the adhesiveness between the all-solid-state battery laminate and the resin layer.

Japanese Patent No. 6363244 Japanese Unexamined Patent Publication No. 2019-192610

In the solid-state power storage device of Patent Document 1, when one of the positive electrode system and the negative electrode system surrounds the other system, the solid-state power storage device is sealed by the heat cycle during charging and discharging. There is a risk that the stopping member will peel off from the metal current collector or solid electrolyte that is the adherend. When such peeling occurs, a phenomenon occurs in which electrolytes and active materials that should be isolated in each system are mixed in other systems. When this phenomenon occurs, the yield and quality of the solid-state power storage device are deteriorated.
On the other hand, in the solid-state battery device in Patent Document 2, in order to ensure the adhesiveness between the all-solid-state battery laminate and the resin layer, an extended portion extending from the laminated portion as a portion overlapping the other layer is provided. It is provided to roughen the surface roughness. However, it is difficult to manufacture the surface roughness of the extended portion so that the surface roughness is sufficient to secure the adhesiveness with the resin layer. In addition, there is a limit to resisting the distortion of the resin layer with a relatively thin extending portion.

The present invention has been made in view of the above circumstances, and provides a solid-state power storage device and a method for manufacturing the same, which can sufficiently secure the airtightness of the all-solid-state battery laminate by the resin layer with a simple configuration. The purpose.

(1) A positive electrode active material layer (for example, a positive electrode active material layer 31 described later) is arranged between two facing solid electrolyte layers (for example, solid electrolyte layers 20 and 20 described later), and a positive electrode collection is provided on the positive electrode active material layer. A positive electrode system (for example, a positive electrode system 30 described later) arranged in contact with an electric body layer (for example, a positive electrode current collector layer 32 described later) and a negative electrode active material layer (for example, a negative electrode active material layer 11 described later) are arranged. The negative electrode system (for example, the negative electrode system 10 described later) arranged so that the negative electrode current collector layer (for example, the negative electrode current collector layer 12 described later) is in contact with the negative electrode active material layer is alternately laminated and laminated. It has a solid-cell battery laminate (for example, a solid-cell battery laminate 1 described later) having a substantially square projection shape in the direction.
Each of the positive electrode system and the negative electrode system is sealed by being surrounded by four sealing members (for example, four sealing members 13, 14, 15, 16 described later) extending along each side of the outer circumference of the square to seal the inside. A frame (for example, a closed frame 17 described later) is provided, and a frame (for example, a closed frame 17 described later) is provided.
The sealing frame includes a three-sided sealing member (for example, a three-sided sealing member 18 described later) in which three-sided sealing members (for example, three-sided sealing members 13, 14, 15 described later) are connected along the outer circumference, and the three-sided sealing member. It has a closing and closing member (for example, a closing and closing member 19 which will be described later) arranged so as to close the open side of the member.
At least one of the three-way sealing member and the closing sealing member has a stepped portion (for example, a stepped portion 153 described later) formed at a contact portion between the two.
Solid power storage device.

(2) The stepped portion is a stepped portion with a notch portion (for example, a notch portion 152 described later) which is a contact surface formed on at least one of both the three-way sealing member and the closing sealing member and which is orthogonal to each other. The solid-state power storage device according to (1), which forms at least one stepped portion composed of a portion (for example, a step portion 153 described later).

(3) The solid-state power storage device according to (1) or (2), wherein the sealing member having the stepped portion is arranged on the negative electrode side of the solid-state battery laminate.

(4) At least one of the three-way sealing member and the closing sealing member is extended from the sealing member main body constituting a part of the sealing frame in the stacking direction of the solid-state battery laminate. The solid-state power storage device according to any one of claims (1) to (3), which is provided with a sheet-like member.

(5) The solid-state power storage device according to any one of (1) to (4), wherein the three-way sealing member and the closing sealing member are configured so that their contact portions can be adhered to each other by heat welding in a contact state. ..

(6) The solid storage device according to any one of (1) to (5), wherein a liquid electrolyte (electrolyte solution) is sealed in at least one of a positive electrode system and a negative electrode system.

(7) The solid-state power storage device according to any one of claims (1) to (6), which is configured to be compatible with a predetermined mobile body.

(8) A method for manufacturing a solid power storage device according to any one of claims (1) to (7), wherein the solid power storage device is manufactured by bonding the three-way sealing member and the closing sealing member by heat welding.

In the solid-state power storage device of (1), at least one of both the three-way sealing member and the closing sealing member has a stepped portion formed at the contact portion between the two. By joining the three-way sealing member and the closing sealing member at this stepped portion, a sufficient contact area is secured at the jointed portion, so that the sealing property in the sealing frame is improved.

In the solid-state power storage device of (2), the step portion is composed of a notch portion and a step portion which are contact surfaces orthogonal to each other formed on at least one of the three-way sealing member and the closing sealing member. At this stepped portion, the three-way sealing member and the closing sealing member are joined in close contact with each other in a plane manner, so that the sealing property at the joint portion of the sealing member is improved.

In the solid-state power storage device (3), sufficient airtightness is ensured by the stepped portion on the negative electrode side of the solid-state battery laminate, which is particularly required to have performance related to airtightness.

In the solid-state power storage device (4), a sheet-like member extended in the stacking direction of the solid-state battery laminate is bent inside the sealed frame and attached along the upper surface of the sealed frame. The airtightness inside is improved.

In the solid-state power storage device of (5), the three-way sealing member and the closing sealing member are adhered by heat welding in a contact state to improve the sealing property in the sealing frame.

(6) By integrating the electrolyte into one of the positive electrode and the negative electrode, it is possible to manufacture a solid storage battery only by superimposing the electrolyte, which facilitates the manufacture.

The solid-state power storage device of (7) can obtain sufficient durability even when applied to a moving body that is required to withstand vibration.

In the method for manufacturing a solid power storage device according to (8), since the three-way sealing member and the closing sealing member are bonded by heat welding, the sealing property in the sealing frame is improved.

It is a perspective view which shows the conceptual structure of the solid-state battery laminate in the solid-state power storage device as embodiment of this invention. FIG. 3 is a side view of the solid-state power storage device of FIG. 1A as viewed in the Y direction of the drawing. It is a top view which shows an example of the negative electrode system which comprises the solid-state electricity storage device as embodiment of this invention. It is a partially enlarged view of FIG. It is a top view which shows another example of the negative electrode system which comprises the solid-state electricity storage device as embodiment of this invention. It is a partially enlarged view of FIG. It is an exploded schematic diagram which shows an example of the structure around the joint part of the three-way sealing member which constitutes the sealing frame of the solid power storage device as the embodiment of this invention, and the closing sealing member. It is a schematic diagram which shows another example of the structure around the joint part of the three-way sealing member which constitutes the sealing frame of the solid power storage device as one embodiment of this invention, and the closing sealing member. It is a figure which shows the state of heat welding the sheet-like member in the sealing member of FIG. 6 to the side surface of a solid electrolyte layer. It is a conceptual diagram which shows one step of the manufacturing process of the negative electrode system which comprises the solid-state electricity storage device as embodiment of this invention. It is a conceptual diagram which shows one step of the manufacturing process of the solid-state battery laminate which comprises the solid-state power storage device as embodiment of this invention. It is a top view which shows an example of the negative electrode system which comprises the solid-state electricity storage device as a comparative example with respect to embodiment of this invention. It is a partially enlarged view of FIG.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a perspective view showing a conceptual configuration of a solid-state battery laminate in a solid-state power storage device according to an embodiment of the present invention. In FIG. 1, it is assumed that the main surface directions of the negative electrode system and the positive electrode system having a substantially flat plate shape are the XY plane directions and the stacking direction is the Z direction.
FIG. 1B is a side view of the solid-state power storage device of FIG. 1A as viewed in the Y direction of the drawing.
The solid-state battery laminate 1 of FIGS. 1A and 1B will be described with reference to FIGS. 9 and 10.
FIG. 9 is a conceptual diagram showing one stage of the manufacturing process of the negative electrode system 10, which is a component of the solid-state battery laminate 1.
FIG. 10 is a conceptual diagram showing one stage of the manufacturing process of the solid-state battery laminate 1 constituting the solid-state power storage device.
The negative electrode system 10 is configured by inserting the negative electrode active material layer 11 and the electrolyte (electrolyte solution) between the two solid electrolyte layers 20 and 20 facing each other. The negative electrode current collector layer 12 is in contact with the negative electrode active material layer 11 so as to be aligned with the negative electrode active material layer 11. Similarly, the positive electrode system 30 is configured by inserting the positive electrode active material layer 31 and the electrolyte (electrolyte solution) between the two solid electrolyte layers 20 and 20 facing each other. The positive electrode current collector layer 32 is in contact with the positive electrode active material layer 31 so as to be aligned with the positive electrode active material layer 31. As shown in FIG. 10, a plurality of negative electrode systems 10 and a plurality of positive electrode systems 30 are alternately laminated (in other words, a plurality of positive electrode systems 30 and a plurality of negative electrode systems are alternately laminated), and the solid-state battery of FIG. 1 is formed. The laminated body 1 is formed. The solid-state battery laminate 1 has a substantially square projection shape in the lamination direction (Z direction in FIG. 1) in the lamination of the negative electrode system 10 and the positive electrode system 30.

FIG. 2 is a plan view showing an example of the negative electrode system 10 of the above-mentioned solid-state battery laminate 1. The negative electrode system 10 is provided with a sealing frame 17 that is surrounded by four sealing members 13, 14, 15, and 16 extending along each side of the outer circumference of the square to seal the inside. The sealing frame 17 has a three-way sealing member 18 in which three-sided sealing members 13, 14 and 15 are connected along the outer circumference, and a closing sealing member 19 arranged so as to close the open side of the three-way sealing member 18. It is composed of. The sealing members 13, 14, 15 and 16 are made of materials having excellent chemical resistance such as PP (polypropylene), PE (polyethylene), epoxy resin, urethane resin, acrylic resin and silicone resin, and excellent adhesiveness and sealing property. It is composed.

The closing sealing member 19 is one sealing member 16 in the sealing frame 17. In the plan view of FIG. 2, the negative electrode active material layer 11 has a shape surrounded by a closed frame 17. Further, the negative electrode current collector layer 12 extends outward from the sealing member 16 (closing and closing member 19).

The positive electrode system 30 is also similar to the negative electrode system 10 in that a sealing frame for sealing the inside is provided by surrounding the positive electrode system 30 with four sealing members extending along each side of the outer circumference of the square. Further, the sealing frame is also configured to include a three-way sealing member in which three-sided sealing members along the outer circumference are connected, and a closing sealing member arranged so as to close the open side of the three-way sealing member. It is the same as the negative electrode system 10. Therefore, with respect to the figure showing the structure of the positive electrode system 30 having the closed frame, FIG. 2 and FIGS. 11 and 12 which are comparative examples with the present embodiment are appropriately referred to. As shown in FIG. 10, in the positive electrode system 30, the lead-out direction of the positive electrode current collector layer 22 is opposite to the lead-out direction of the negative electrode current collector layer 12 in the negative electrode system 10.

In the solid-state power storage device of the present invention, at least one of the positive electrode system 30 and the negative electrode system 10 may be sealed, but it is more preferable that both are sealed.

The three-way sealing member 18 has a substantially U-shape or a C-shape when viewed from the projection shape on the XY plane assumed in FIG. 1, that is, the projection shape in the stacking direction described above. The open side of this shape is closed by the closing sealing member 19. Further, the projected shapes of the sealing members 13, 14, 15 and the closing sealing member 19 constituting the three-way sealing member 18 on the XY plane, that is, the above-mentioned projected shapes in the stacking direction are all substantially square. Is.

In the present embodiment, in order to ensure the closing, at least one of the three-way sealing member 18 and the closing sealing member 19 is formed with a stepped portion at the contact portion between the two. A specific example of this stepped portion is shown in FIG. 2 and FIG. 3 which is a partially enlarged view thereof.

In the examples of FIGS. 2 and 3, a step portion is formed at each end (left end in the drawing) of the parallel sealing members 13 and 15 of the three-way sealing member 18. In FIG. 3, the vicinity of the left end portion 151 of the sealing member 15 is shown as a partially enlarged view. A cut cut out at a certain depth in the thickness direction of the sealing member 15 at a contact portion with a corner portion 192 of the end portion (lower end portion 191 in the figure) of the closing sealing member 19 in the vicinity of the left end portion 151 of the sealing member 15. The notch 152 is formed. The sealing member 15 is formed with a stepped portion 153 at a contact portion with the closing sealing member 19 by a notch portion 152.

The sealing member 15 and the closing sealing member 19 are tightly joined so that the corner portion 192 of the lower end portion 191 of the closing sealing member 19 fits tightly into the notch portion 152 forming the step portion 153 in this way. .. The dimension (notch width) of the notch portion 152 along the longitudinal direction of the sealing member 15 is smaller than the thickness dimension of the closing sealing member 19. Therefore, as shown in the drawing, the outer edge in the longitudinal direction (left edge 193 in the figure) of the closing sealing member 19 is not aligned with the left end portion 151 of the sealing member 15 and is located on the outside (left side in the drawing).

As for the sealing member 13 of the three-way sealing member 18, a notch 132 is formed in the vicinity of the left end 131 of the sealing member 13 as in the sealing member 15. A step portion 133 is formed at a contact portion with the closing sealing member 19 by the notch portion 132. The sealing member 13 and the closing sealing member 19 are tightly joined so that the corner portion 195 of the upper end portion 194 of the closing sealing member 19 fits tightly into the notch portion 132 forming the step portion 133 in this way.

The notch portion 152 and the step portion 153 formed on the left end portion 151 side of the sealing member 15 form a rectangular surface orthogonal to each other. In the joint portion between the sealing member 15 and the closing sealing member 19 in FIGS. 2 and 3, the joint surface (notch portion 152 and step portion 153) on the sealing member 15 side forming a rectangular surface orthogonal to each other is formed. In a state of being in contact with the corresponding surface on the closing sealing member 19 side, the two contacting members are adhered by heat welding. For this reason, the contact area is larger than when flat surfaces having no steps are brought into contact with each other, and a strong heat-welded portion is formed in a wider range, so that the airtightness is excellent.
Further, the notch portion 132 formed on the left end portion 131 side of the sealing member 13 and the step portion 133 form a rectangular surface orthogonal to each other. Therefore, similarly to the joint portion between the sealing member 15 and the closing sealing member 19, the joining surface (notch portion 132 and step portion 133) on the sealing member 13 side forming a rectangular surface orthogonal to each other is the closing sealing member 19. In a state of being in contact with the corresponding surface on the side, the two members in contact are adhered by heat welding. For this reason, the contact area is larger than when flat surfaces having no steps are brought into contact with each other, and a strong heat-welded portion is formed in a wider range, so that the airtightness is excellent.

4 and 5 show another example of a stepped portion formed at the contact portion between the three-way sealing member and the closing sealing member.
In the examples of FIGS. 4 and 5, no step portion is formed at each end portion (each left end portion 131, 151 in the figure) of the parallel sealing members 13 and 15 of the three-way sealing member 18, and the closing sealing member 19 A step is formed at the end. In FIG. 5, the vicinity of the lower end portion 191 of the closing sealing member 19 is shown as a partially enlarged view.

A cutout was made at a certain depth in the thickness direction of the closing sealing member 19 at a contact portion with a corner portion 154 of the closing portion 15 (left end portion 151 in the figure) in the vicinity of the lower end portion 191 of the closing sealing member 19. A notch 196 is formed. In the closing sealing member 19, a stepped portion 197 is formed at a contact portion with the sealing member 15 by a notch portion 196. The closing sealing member 19 and the sealing member 15 are tightly joined so that the corner portion 154 of the left end portion 151 of the sealing member 15 fits tightly into the notch portion 196 forming the step portion 197 in this way.

The dimension (depth) of the notch portion 196 along the longitudinal direction of the closing sealing member 19 is smaller than the thickness dimension of the sealing member 15. Therefore, as shown in the drawing, the outer edge in the longitudinal direction (lower end edge 155 in the figure) of the sealing member 15 is not aligned with the lower end portion 191 of the closing sealing member 19 and is located on the outer side (lower side in the drawing).

As for the upper end portion 194 side of the closing sealing member 19, a notch portion 198 is formed in the upper end portion 194 of the closing sealing member 19 as in the case of the lower end portion 191 side. A step portion 199 is formed at a contact portion with the sealing member 13 by the notch portion 198. The closing sealing member 19 and the sealing member 13 are tightly joined so that the corner portion 134 of the left end portion 131 of the sealing member 13 fits into the notch portion 198 forming the step portion 199 without a gap.

The notch portion 196 and the step portion 197 formed on the lower end portion 191 side of the closing sealing member 19 form a rectangular surface orthogonal to each other. In the joint portion between the closing seal member 19 and the sealing member 15 in FIGS. 4 and 5, the joint surface on the closing sealing member 19 side (notch 196 and stepped portion 197) forming a rectangular surface orthogonal to each other in this way. Is in contact with the corresponding surface on the sealing member 15 side, and both of the contacted members are bonded by heat welding. For this reason, the contact area is larger than when flat surfaces having no steps are brought into contact with each other, and a strong heat-welded portion is formed in a wider range, so that the airtightness is excellent.
Further, the notch portion 198 formed on the upper end portion 194 side of the closing sealing member 19 and the stepped portion 199 form a rectangular surface orthogonal to each other. Therefore, similarly to the joint portion between the sealing member 15 and the closing sealing member 19, the joining surface (notch portion 198 and step portion 199) on the closing sealing member 19 side forming a rectangular surface orthogonal to each other is the sealing member 13. In a state of being in contact with the corresponding surface on the side, the two members in contact are adhered by heat welding. For this reason, the contact area is larger than when flat surfaces having no steps are brought into contact with each other, and a strong heat-welded portion is formed in a wider range, so that the airtightness is excellent.

In the solid-state power storage device of the present invention, at least one of the four sealing members 13, 14, 15, and 16 as described above extends upward from the upper end outer edge side of the sealing member main body forming the sealing frame 17. It may take the form of having a protruding sheet-like member. FIG. 6 shows an example of a sealing member having such a sheet-like member.

FIG. 6 is an exploded schematic view showing an example of the configuration of the sealed frame 17 of the solid-state power storage device according to the embodiment of the present invention. FIG. 6 schematically shows an example of the configuration around the joint portion between the three-way sealing member 18 (of which the sealing member 15) and the closing sealing member 19 constituting the sealing frame 17. The sealing member 15 is a sheet-like member 150a extending upward from the upper end outer edge side of the sealing member main body 150, which is a component forming the sealing frame 17, and a sheet-like member extending downward from the lower end outer edge side of the sealing member main body 150. It has a member 150b. Here, "upper" means "upper" in the stacking direction of the solid-state battery laminate 1, and "lower" means "lower" in the stacking direction of the solid-state battery laminate 1. The sealing member main body 150 and the sheet-shaped members 150a and 150b of the sealing member 15 are made of PP (polypropylene) or PE (polyethylene) and are integrally connected. The sheet-shaped members 150a and 150b are thin enough to bend inward of the sealed frame 17 by their own weight. From the viewpoint, in the solid-state power storage device according to the embodiment of the present invention, the sheet-shaped members 150a and 150b are arranged on the negative electrode side of the solid-state battery laminate 1.

The sheet-shaped member 150a may be provided on the upper end outer edge side of the closing sealing member 19, or the sheet-shaped member 150b may be provided on the lower end outer edge side of the closing sealing member 19.

The upward and downward lengths of the sheet-shaped members 150a and 150b are preferably shorter than the sum of the thickness of the solid electrolyte layer 20 and the width of the sealing member in the lateral direction, and the thickness of the solid electrolyte layer 20. Shorter is more preferable.

The joint portion between the sealing member 15 and the closing sealing member 19 in the example of FIG. 6 has a form in which notches (stepped portions) formed on both the sealing member 15 side and the closing sealing member 19 side are joined to each other. I'm doing it. That is, on the sealing member 15 side, a stepped portion 153a is formed by the notched portion 152a having a shape as shown in the example of FIG. A stepped portion 197a formed by a notched portion 196a having a shape as shown in the example of FIG. 3 is also formed on the closing sealing member 19 side. In the above-mentioned joint portion in FIG. 6, the stepped portions 153a and 197a provided in one step on both the sealing member 15 side and the closing sealing member 19 side are in contact with the notched portions 196a and 152a of the other party. Joining is done at the part.

The notch portion 152a and the step portion 153a formed on the sealing member 15 side form a rectangular surface orthogonal to each other. Further, the notch portion 196a and the step portion 197a formed on the closing / sealing member 19 side form a rectangular surface orthogonal to each other. In the above-mentioned joint portion in FIG. 6, the joint surface (notch portion 152a and step portion 153) on the sealing member 15 side and the joint surface (notch) on the closing sealing member 19 side forming rectangular surfaces orthogonal to each other in this way. In a state where the portion 196a and the stepped portion 197a) are in contact with each other, the two members in contact with each other are adhered by heat welding. For this reason, the contact area is larger than when flat surfaces having no steps are brought into contact with each other, and a strong heat-welded portion is formed in a wider range, so that the airtightness is excellent.

FIG. 7 is a schematic view showing another example of the configuration around the joint between one sealing member of the three-way sealing member and the closing sealing member. In the joint portion of both the sealing member 15 and the closing sealing member 19 in the example of FIG. 6, the stepped portions 153a and 197a provided in each step are in contact with the notch portions 196a and 152a of the other party. Joining was done at the part. On the other hand, in the joint portion of FIG. 7, two steps of stepped portions 197b and 197c are formed on the closing and sealing member 19 side. The step portion 197b is formed as a step with respect to the notch portion 196b, and the step portion 197c is formed as a step with respect to the notch portion 196c. The step portion 153a on the sealing member 15 side shown by the broken line shown with the two-step step portion 197b and 197c on the closing sealing member 19 side is the one-step step portion in the example of FIG.

The two-stage stepped portions 197b and 197c formed on the closing and sealing member 19 side each form a rectangular surface orthogonal to the corresponding notched portions 196b and 196c. Therefore, as in the case of the joint portion described with reference to FIGS. 2 to 4, the contact area is larger than when the flat surfaces having no steps are brought into contact with each other, and strong heat welding is performed over a wider range. Excellent airtightness because the part is formed.

The three-way sealing member 18 and the closing sealing member 19 constituting the sealing frame 17 are adhered to the solid electrolyte layer 20 by heat welding on the upper surface and the lower surface of the member. Here, the upper surface is an upper surface in the stacking direction of the solid-state battery laminate 1, and the lower surface is a lower surface in the stacking direction of the solid-state battery laminate 1.

In the joint portion shown in FIGS. 2 to 7, one of the three-way sealing members and the closing sealing member have a joining structure by heat welding. Therefore, the solid-state power storage device made of the solid-state battery laminate 1 having a high yield strength against vibration and the like and having this bonding structure is well suited for use as an electric energy source in a moving body such as an electric vehicle.

FIG. 8 is a diagram showing how the sheet-shaped members 150a and 150b in the sealing member 15 of FIG. 6 are heat-welded to the side surfaces of the solid electrolyte layer 20. The sheet-like member 150a is a thin sheet-like body made of PP (polypropylene) or PE (polyethylene), and can be adhered to the side surface of the solid electrolyte layer 20 arranged above by heat welding.
The sheet-like member 150b is a thin sheet-like body made of PP (polypropylene) or PE (polyethylene), and can be adhered to the side surface of the solid electrolyte layer 20 arranged below by heat welding.

With respect to FIGS. 9 and 10, the solid-state battery laminate 1 has been described with reference to FIGS. 1 and FIG. In the above description, for convenience, the positive electrode system 30 is laminated under the negative electrode system 10, and a plurality of the negative electrode system 10 and the positive electrode system 30 are alternately laminated in this way. However, the above description does not mean that the stacking order of the negative electrode and the positive electrode is defined. The negative electrode system 10 is laminated under the positive electrode system 30, and a plurality of alternating laminates in this form can be laminated. Further, a positive electrode sandwiched between solid electrolytes and sealed may be laminated with the negative electrode. Further, it is also possible to stack a negative electrode and a solid electrolyte, and a solid electrolyte and a negative electrode which are laminated and sealed in the above-mentioned order. In addition, a process different from the periodic structure in which the lowermost surface and the uppermost surface of the laminated body are laminated in the middle is applied.

Next, the action and effect of the solid-state power storage device according to the embodiment of the present invention will be described in comparison with the solid-state power storage device of the comparative example.
FIG. 11 is a plan view showing an example of a negative electrode system constituting a solid-state power storage device as a comparative example with respect to the embodiment of the present invention. Further, FIG. 12 is a partially enlarged view of FIG. In FIGS. 11 and 12, the parts corresponding to those in FIGS. 2 and 3 are designated by the same reference numerals.

In FIGS. 11 and 12, the lower end portion 191 and the upper end portion 194 of the closing sealing member 19 each have a flat surface. The flat surface of the lower end portion 191 of the closing sealing member 19 comes into contact with the flat surface of the side surface near the left end portion 151 of the sealing member 15. Similarly, the flat surface of the upper end portion 194 of the closing sealing member 19 comes into contact with the flat surface of the side surface near the left end portion 131 of the sealing member 13. The closing sealing member 19, the sealing member 15, and the sealing member 13 are joined at these abutting points. Since the joint surface is flat, the contact area of both members to be joined is smaller than that in which the stepped portions 153 and 133 are formed by the notches 152 and 132 as shown in FIGS. 2 and 3. In other words, in the embodiments of FIGS. 2 and 3, the contact area is increased by the stepped portions 153 and 133 on the joint surface, and a sufficient sealing capacity is secured as compared with the comparative example. This point is the same for any of the joints in FIGS. 2 to 7 according to the embodiment of the present invention.

According to the solid-state power storage device of the present embodiment, the following effects are obtained.
In the solid-state power storage device of (1), a step portion 153 is formed at a contact portion between the three-way sealing member 18 and the closing sealing member 19 at least one of them. By joining the three-way sealing member 18 and the closing sealing member 19 at the step portion 153, a sufficient contact area is secured at the jointed portion, so that the sealing property inside the sealing frame is improved.

In the solid-state power storage device of (2), the step portion 153 includes a notch portion 152 and a step portion 153, which are contact surfaces orthogonal to each other formed on at least one of the three-way sealing member 18 and the closing sealing member 19. Since the three-way sealing member 18 and the closing sealing member 19 are joined in close contact with each other at the step portion 153, the sealing property at the joining portion of the sealing member is improved.

In the solid-state power storage device (3), sufficient airtightness is ensured by the step portion 153 on the negative electrode side of the solid-state battery laminate 1, which is particularly required to have performance related to airtightness.

In the solid-state power storage device (4), 150a and 150b of sheet-like members extended in the stacking direction of the solid-state battery laminate 1 are placed along the upper surface of the solid electrolyte layer 20, and the sheet-like member 150b is a solid electrolyte. By using the layer 20 so as to be attached along the lower surface of the layer 20, the airtightness in the negative electrode system is improved.

In the solid power storage device of (5), the three-way sealing member 18, the closing sealing member 19, and the solid electrolyte layer 20 are adhered by heat welding in a contact state to improve the sealing property in the negative electrode system.

In the solid-state power storage device of (6), by integrating the electrolyte into one of the positive electrode and the negative electrode, it is possible to manufacture the solid storage battery only by superimposing it, so that the manufacturing becomes easy.

The solid-state power storage device of (7) can obtain sufficient durability even when applied to a moving body that is required to withstand vibration.

In the method for manufacturing the solid storage device according to (8), since the three-way sealing member 18 and the closing sealing member 19 are bonded by heat welding, the sealing property inside the sealing frame 17 is improved.

Although one embodiment of the present invention has been described above, the present invention is not limited to this. Within the scope of the gist of the present invention, the detailed configuration may be changed as appropriate. For example, in the above example, the sheet-shaped member 150a is provided so as to extend upward from the upper end outer edge side of the sealing member main body 150 which is a component of the sealing frame 17, but the sealing member 15 (sealing member main body) is provided. A sheet-like body of PP or PE, which is the same material as the part 150), may be arranged at a portion where the sheet-like member 150a is arranged so as to be heat-welded.

1 ... Solid-state battery laminate 10 ... Negative electrode system 11 ... Negative electrode active material layer 12 ... Negative electrode current collector layer 13, 14, 15, 16 ... Sealing member 17 ... Sealing frame 18 ... Three-way sealing member 19 ... Closing sealing member 20 ... Solid Electrode layer 30 ... Positive electrode system 31 ... Positive electrode active material layer 32 ... Positive electrode current collector layer 150 ... Sealing member main body 150a ... Sheet-like member 152 ... Notch 153 ... Stepped portion

Claims (8)

A positive electrode system in which a positive electrode active material layer is arranged between two solid electrolyte layers facing each other and a positive electrode current collector layer is arranged in contact with the positive electrode active material layer, and a negative electrode system in which a negative electrode active material layer is arranged and a negative electrode is placed on the negative electrode active material layer. It has a solid battery laminate in which the negative electrode systems arranged in contact with the current collector layers are alternately laminated, and the projected shape in the stacking direction is approximately square.
Each of the positive electrode system and the negative electrode system is provided with a sealing frame that seals the inside by surrounding the positive electrode system and the negative electrode system with four sealing members extending along each side of the outer circumference of the square.
The sealing frame has a three-way sealing member in which three-sided sealing members along the outer circumference are connected, and a closing-sealing member arranged so as to close the open side of the three-way sealing member.
At least one of the three-way sealing member and the closing sealing member has a stepped portion formed at a contact portion between the two.
Solid power storage device. The stepped portion is a stepped portion having at least one step formed by a notch portion and a stepped portion which are mutually orthogonal contact surfaces formed on at least one of the three-way sealing member and the closing sealing member. The solid-state power storage device according to claim 1. The solid-state power storage device according to claim 1 or 2, wherein the sealing member having the step portion is arranged on the negative electrode side of the solid-state battery laminate. The sealing member of at least one of the three-way sealing member and the closing sealing member is a sheet-like member extending from the sealing member main body constituting a part of the sealing frame in the stacking direction of the solid-state battery laminate. The solid-state power storage device according to any one of claims 1 to 3, wherein the solid-state power storage device is provided. The solid power storage device according to any one of claims 1 to 4, wherein the three-way sealing member and the closing sealing member are configured so that the contact portions thereof can be adhered to each other by heat welding in a contact state. The solid power storage device according to any one of claims 1 to 5, wherein an electrolytic solution is sealed in at least one of the positive electrode system and the negative electrode system. The solid-state power storage device according to any one of claims 1 to 5, which is configured to fit a predetermined mobile body. A method for manufacturing a solid power storage device according to any one of claims 1 to 7, wherein the solid power storage device is manufactured by combining the three-way sealing member and the closing sealing member by heat welding.

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