JP7328167B2 - Solid state power storage device and manufacturing method thereof - Google Patents

Description

The present invention relates to a solid power storage device and a manufacturing method thereof.

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 between the positive electrode system and the negative electrode system are exchanged through the solid electrolyte during charging and discharging (for example, , see Patent Document 1).

On the other hand, in a solid power storage device in which the side surface of the all-solid battery laminate is covered with a resin layer, a technique for improving the adhesion between the all-solid 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 has a laminated portion as a portion that overlaps with another adjacent layer and a laminated portion that extends beyond the other layer. An extension is provided. The surface roughness of the extending portion is roughened to ensure adhesion between the all-solid battery laminate and the resin layer.

Japanese Patent No. 6363244 JP 2019-192610 A

In the solid state power storage device of Patent Document 1, when adopting a cell structure in which either one of the positive electrode system and the negative electrode system surrounds the other system, the sealing in the solid power storage device is affected by thermal cycles during charging and discharging. There is a risk that the stopper member will peel off from the metal current collector or the solid electrolyte that is the adhered portion. When such peeling occurs, a phenomenon occurs in which electrolytes and active materials that should be isolated for each system are mixed into other systems. If this phenomenon occurs, it will lead to a decrease in yield and a decrease in quality in the manufacture of solid power storage devices.
On the other hand, in the solid-state battery device in Patent Document 2, in order to ensure the adhesion between the all-solid-state battery laminate and the resin layer, an extension portion that extends from the laminate portion as a portion that overlaps with the other layers is provided. is provided to roughen the surface roughness. However, it is difficult in terms of manufacturing to make the surface roughness of the extending portion sufficiently rough to ensure the adhesiveness to the resin layer. In addition, there is a limit to resisting distortion of the resin layer with a relatively thin extending portion.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a solid-state electric storage device and a method of manufacturing the same, which can sufficiently ensure sealing performance of an all-solid-state battery stack by a resin layer with a simple configuration. aim.

(1) A cathode active material layer (for example, a cathode active material layer 31 to be described later) is arranged between two facing solid electrolyte layers (for example, solid electrolyte layers 20, 20 to be described later), and the cathode active material layer is provided with a cathode collector. A positive electrode system (for example, a positive electrode system 30 to be described later) arranged in contact with a current layer (for example, a positive electrode current collector layer 32 to be described later) and a negative electrode active material layer (for example, a negative electrode active material layer 11 to be described later). A negative electrode system (for example, a negative electrode system 10 described later) in which a negative electrode current collector layer (for example, a negative electrode current collector layer 12 described later) is disposed in contact with the negative electrode active material layer is alternately laminated and laminated. Having a solid battery stack (for example, a solid battery stack 1 described later) whose projected shape in the direction is approximately square,
Each of the positive electrode system and the negative electrode system is enclosed by four sealing members (for example, four sealing members 13, 14, 15, and 16 to be described later) extending along each side of the outer periphery of the square to seal the inside. A frame (for example, a sealing frame 17 described later) is provided,
The sealing frame includes a three-side sealing member (for example, a three-side sealing member 18 described later) in which three-side sealing members (for example, three-side sealing members 13, 14, and 15 described later) are connected along the outer periphery, and the three-side sealing member a closing sealing member (for example, a closing sealing member 19 described below) arranged to close the open side of the member;
At least one of the three-way sealing member and the closed sealing member has a stepped portion (for example, a stepped portion 153 described later) at the contact portion between the two.
Solid state power storage device.

(2) The stepped portion includes a notch portion (for example, a notch portion 152 to be described later) that is a mutually orthogonal contact surface formed on at least one of the three-way sealing member and the closed sealing member and the stepped portion. The solid-state power storage device according to (1), which forms at least one stepped portion formed by a portion (for example, a stepped portion 153 to be 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 stack.

(4) At least one of the three-sided sealing member and the closing sealing member has a sealing member body portion that is a part of the sealing frame and extends in the stacking direction of the solid battery stack. The solid state electric storage device according to any one of claims (1) to (3), further comprising a sheet member.

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

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

(7) The solid-state power storage device according to any one of claims (1) to (6), which is adapted to a predetermined moving object.

(8) A method of manufacturing a solid state electric storage device according to any one of (1) to (7), wherein the three-way sealing member and the closed sealing member are joined by heat welding.

In the solid power storage device of (1), at least one of the three-way sealing member and the closed sealing member has a stepped portion at the contact portion between the two. By joining the three-way sealing member and the closed sealing member at this stepped portion, a sufficient contact area is secured at the joint portion, so that the sealing performance within the sealing frame is improved.

In the solid power storage device of (2), the stepped portion is composed of the notch portion and the stepped portion, which are mutually orthogonal contact surfaces formed in at least one of the three-way sealing member and the closed sealing member. At this stepped portion, the three-way sealing member and the closed sealing member are joined in close contact with each other, thereby improving the sealing performance at the joining portion of the sealing members.

In the solid power storage device of (3), the stepped portion ensures sufficient sealing performance on the negative electrode side of the solid battery stack, which particularly requires sealing performance.

In the solid-state electric storage device of (4), the sheet-shaped member provided extending in the stacking direction of the solid-state battery stack is bent inward of the sealing frame and adhered along the upper surface of the sealing frame. Improves airtightness inside.

In the solid state electric storage device of (5), the three-way sealing member and the closed sealing member are bonded by heat welding in a contact state, so that the sealing performance within the sealing frame is improved.

(6) Integrating the electrolyte with either the positive electrode or the negative electrode makes it possible to manufacture a solid storage battery simply by stacking them, which facilitates manufacturing.

The solid-state power storage device of (7) can provide sufficient durability even when applied to a moving body that requires resistance to vibration.

In the method of manufacturing a solid state electric storage device of (8), since the three-way sealing member and the closed sealing member are joined by heat welding, the sealing performance within the sealing frame is improved.

1 is a perspective view showing a conceptual configuration of a solid battery stack in a solid power storage device as an embodiment of the present invention; FIG. It is the side view which looked at the Y direction of illustration of the solid-state electrical storage apparatus of FIG. 1A. 1 is a plan view showing an example of a negative electrode system that constitutes a solid power storage device as an embodiment of the present invention; FIG. FIG. 3 is a partially enlarged view of FIG. 2; FIG. 4 is a plan view showing another example of the negative electrode system that constitutes the solid-state power storage device according to the embodiment of the present invention; FIG. 5 is a partially enlarged view of FIG. 4; FIG. 2 is an exploded schematic view showing an example of the configuration around the joint between the three-way sealing member and the closed sealing member that constitute the sealing frame of the solid power storage device according to the embodiment of the present invention; FIG. 4 is a schematic diagram showing another example of the configuration around the joint portion between the three-way sealing member and the closed sealing member that constitute the sealing frame of the solid power storage device as one embodiment of the present invention. FIG. 7 is a view showing how the sheet member in the sealing member of FIG. 6 is thermally welded to the side surface of the solid electrolyte layer; FIG. 2 is a conceptual diagram showing one stage of the manufacturing process of the negative electrode system that constitutes the solid-state power storage device according to the embodiment of the present invention; FIG. 2 is a conceptual diagram showing one stage of a manufacturing process of a solid battery stack constituting a solid state electric storage device as an embodiment of the present invention; FIG. 4 is a plan view showing an example of a negative electrode system that constitutes a solid-state power storage device as a comparative example for the embodiment of the present invention; FIG. 12 is a partially enlarged view of FIG. 11;

An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a perspective view showing a conceptual configuration of a solid battery stack in a solid power storage device as one embodiment of the present invention. In FIG. 1, it is assumed that the direction of the main surfaces of the negative electrode system and the positive electrode system, both of which will be described later, is the XY plane direction, and the stacking direction is the Z direction.
FIG. 1B is a side view of the solid-state power storage device of FIG. 1A viewed in the Y direction of the drawing.
The solid battery stack 1 of FIGS. 1A and 1B will be described with reference to FIGS. 9 and 10 as well.
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 battery stack 1. As shown in FIG.
FIG. 10 is a conceptual diagram showing one stage of the manufacturing process of the solid battery stack 1 that constitutes the solid power storage device.
The negative electrode system 10 is configured by inserting a negative electrode active material layer 11 and an electrolyte (electrolyte solution) between two solid electrolyte layers 20, 20 facing each other. The negative electrode current collector layer 12 is arranged along the negative electrode active material layer 11 so as to be in contact therewith. Similarly, the positive electrode system 30 is configured by inserting a positive electrode active material layer 31 and an electrolyte (electrolytic solution) between two facing solid electrolyte layers 20 , 20 . The positive electrode collector layer 32 is arranged along the positive electrode active material layer 31 so as to be in contact therewith. As shown in FIG. 10, a plurality of negative electrode systems 10 and positive electrode systems 30 are alternately stacked (in other words, a plurality of positive electrode systems 30 and negative electrode systems 10 are alternately stacked) to form the solid-state battery of FIG. A laminate 1 is constructed. In the solid battery stack 1, the projected shape in the stacking direction (the Z direction in FIG. 1) of the stack of the negative electrode system 10 and the positive electrode system 30 forms a substantially square shape.

FIG. 2 is a plan view showing an example of the negative electrode system 10 of the solid battery stack 1 described above. 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 rectangular outer periphery to seal the inside. The sealing frame 17 has a three-way sealing member 18 in which three side sealing members 13, 14, 15 along the outer periphery are connected, and a closing sealing member 19 arranged to close the open side of the three-way sealing member 18. consists of The sealing members 13, 14, 15, and 16 are made of materials such as PP (polypropylene), PE (polyethylene), epoxy resin, urethane resin, acrylic resin, silicone resin, etc., which are excellent in chemical resistance, adhesiveness, and airtightness. Configured.

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

Similarly to the negative electrode system 10, the positive electrode system 30 is also provided with a sealing frame that surrounds and seals the inside with four sealing members extending along each side of the rectangular outer periphery. In addition, the sealing frame includes a three-sided sealing member in which sealing members on three sides are connected along the outer circumference, and a closed sealing member disposed so as to close the open side of the three-sided sealing member. It is the same as the negative electrode system 10 . For this reason, FIG. 2 and FIGS. 11 and 12, which are comparative examples with the present embodiment, are appropriately used as the diagrams showing the configuration having the sealing frame in the positive electrode system 30 . As shown in FIG. 10 , in the positive electrode system 30 , the lead-out direction of the positive electrode collector layer 22 is opposite to the lead-out direction of the negative electrode collector layer 12 in the negative electrode system 10 .

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

The above-described sealing frame 17 has a projected shape on the XY plane assumed in FIG. 1, that is, a projected shape in the above-described stacking direction. , and the open side of this shape is closed with a closing sealing member 19 . In addition, the projection shape of each of the sealing members 13, 14, 15 constituting the three-way sealing member 18 and the closed sealing member 19 onto the XY plane, that is, the projected shape of the above-described stacking direction, is generally rectangular. is.

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

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

The sealing member 15 and the closing and sealing member 19 are tightly joined together so that the corner portion 192 of the lower end portion 191 of the closing and sealing member 19 fits into the notch portion 152 forming the stepped portion 153 without any gap. . The notch portion 152 has a dimension (notch width) along the longitudinal direction of the sealing member 15 smaller than the thickness dimension of the closing sealing member 19 . Thus, as shown, the longitudinal outer edge (left edge 193 in the figure) of the closure member 19 is not aligned with the left end 151 of the closure member 15 and is located outside (left in the figure).

The sealing member 13 of the three-way sealing member 18 also has a notch 132 near the left end 131 of the sealing member 13 as in the sealing member 15 . A stepped portion 133 is formed at the contact portion with the closing and sealing member 19 by the notch portion 132 . In this way, the sealing member 13 and the sealing member 19 are tightly joined together 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 stepped portion 133 .

A notch portion 152 and a stepped portion 153 formed on the left end portion 151 side of the sealing member 15 form rectangular surfaces orthogonal to each other. 2 and 3, at the junction between the sealing member 15 and the closed sealing member 19, the joint surfaces (notch 152 and stepped portion 153) on the side of the sealing member 15 forming rectangular surfaces perpendicular to each other are formed. While in contact with the corresponding surface on the closing sealing member 19 side, the two contacting members are bonded together by heat welding. For this reason, the contact area is larger than when flat surfaces without steps are brought into contact with each other, and a strong thermally welded portion is formed in a wider range, resulting in excellent airtightness.
The notch 132 and the stepped portion 133 formed on the left end portion 131 side of the sealing member 13 form rectangular surfaces perpendicular to each other. Therefore, as in the joint portion between the sealing member 15 and the closed sealing member 19, the joint surface (the notch portion 132 and the step portion 133) on the side of the sealing member 13 forming rectangular surfaces orthogonal to each other is the closed sealing member 19. In a state of contact with the corresponding surfaces on the sides, the two contacting members are bonded together by heat welding. For this reason, the contact area is larger than when flat surfaces without steps are brought into contact with each other, and a strong thermally welded portion is formed in a wider range, resulting in excellent airtightness.

4 and 5 show other examples of stepped portions formed at the contact portions of both the three-way sealing member and the closed sealing member.
4 and 5, the parallel sealing members 13 and 15 of the three-way sealing member 18 do not have a stepped portion at each end (the left ends 131 and 151 in the figure), and the closed sealing member 19 does not have a stepped portion. A stepped portion is formed at the end. FIG. 5 shows a partially enlarged view of the lower end portion 191 of the closing sealing member 19 and its vicinity.

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

The notch 196 has a dimension (depth) along the longitudinal direction of the closing sealing member 19 smaller than the thickness dimension of the sealing member 15 . Thus, as shown, the longitudinally outer edge (bottom edge 155 in the figure) of the closure member 15 is not aligned with the bottom edge 191 of the closure closure member 19 and is located outside (under in the figure).

A notch portion 198 is formed in the upper end portion 194 of the closing and sealing member 19 on the side of the upper end portion 194 of the closing and sealing member 19 as well as on the side of the lower end portion 191 . A stepped portion 199 is formed at the contact portion with the sealing member 13 by the notch portion 198 . In this manner, the corner portion 134 of the left end portion 131 of the sealing member 13 is fitted into the notch portion 198 forming the stepped portion 199 so that the closing sealing member 19 and the sealing member 13 are tightly joined.

A notch portion 196 and a stepped portion 197 formed on the lower end portion 191 side of the closing sealing member 19 form rectangular surfaces orthogonal to each other. 4 and 5, at the junction between the closing and sealing member 19 and the sealing member 15, the joining surfaces (notch 196 and stepped portion 197) on the side of the closing and sealing member 19 forming rectangular surfaces perpendicular to each other are in contact with the corresponding surface on the side of the sealing member 15, and the two contacting members are bonded together by heat welding. For this reason, the contact area is larger than when flat surfaces without steps are brought into contact with each other, and a strong thermally welded portion is formed in a wider range, resulting in excellent airtightness.
A notch portion 198 and a stepped portion 199 formed on the upper end portion 194 side of the closing and sealing member 19 form rectangular surfaces perpendicular to each other. Therefore, as in the joint portion between the sealing member 15 and the closing sealing member 19, the joint surface (notch portion 198 and stepped portion 199) on the closing sealing member 19 side forming rectangular surfaces orthogonal to each other is the sealing member 13. In a state of contact with the corresponding surface on the side, the two contacting members are bonded together by heat welding. For this reason, the contact area is larger than when flat surfaces without steps are brought into contact with each other, and a strong thermally welded portion is formed in a wider range, resulting in excellent airtightness.

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

FIG. 6 is an exploded schematic diagram showing an example of the configuration of the sealing frame 17 of the solid-state power storage device as an embodiment of the present invention. FIG. 6 schematically illustrates an example of the configuration around the junction between the three-way sealing member 18 (the sealing member 15 of them) and the closed sealing member 19 that constitute the sealing frame 17 . The sealing member 15 includes a sheet-like member 150a extending upward from the outer edge of the upper end of the sealing member body 150, which is a component of the sealing frame 17, and a sheet-like member 150a extending downward from the outer edge of the lower end of the sealing member body 150. It has a member 150b. Here, "upper" means upward in the stacking direction of the solid battery stack 1, and "downward" means downward in the stacking direction of the solid battery stack 1. As shown in FIG. The sealing member main body 150 and the sheet-like members 150a and 150b of the sealing member 15 are made of PP (polypropylene) or PE (polyethylene) and are integrally connected. The sheet members 150a and 150b are so thin that they bend inwardly of the sealing frame 17 under their own weight. From a different point of view, in the solid power storage device as an embodiment of the present invention, the sheet members 150 a and 150 b are arranged on the negative electrode side of the solid battery stack 1 .

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

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

The joint between the sealing member 15 and the closed sealing member 19 in the example of FIG. None. That is, on the side of the sealing member 15, a step portion 153a is formed by a notch portion 152a shaped like the example in FIG. A step portion 197a is also formed on the closing sealing member 19 side by a notch portion 196a shaped like the example in FIG. 6, the stepped portions 153a and 197a provided on both the sealing member 15 side and the closed sealing member 19 side are in contact with the corresponding notch portions 196a and 152a. Joining is performed at the part.

The notch portion 152a and the stepped portion 153a formed on the sealing member 15 side form rectangular surfaces orthogonal to each other. The notch 196a and the stepped portion 197a formed on the closing sealing member 19 side form rectangular surfaces perpendicular to each other. 6, the joint surface (notch 152a and stepped portion 153) on the side of the sealing member 15 and the joint surface (notch 153) on the side of the sealing member 19 forming rectangular surfaces perpendicular to each other. While the portion 196a and the stepped portion 197a) are in contact with each other, the contacting members are bonded together by thermal welding. For this reason, the contact area is larger than when flat surfaces without steps are brought into contact with each other, and a strong thermally welded portion is formed in a wider range, resulting in excellent airtightness.

FIG. 7 is a schematic diagram showing another example of the configuration around the junction between one of the three-way sealing members and the closed sealing member. In the joints of both the sealing member 15 and the closed sealing member 19 in the example of FIG. Jointing was performed at the part. On the other hand, in the joint shown in FIG. 7, two steps 197b and 197c are formed on the 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. A stepped portion 153a on the side of the sealing member 15 shown by broken lines, which is joined to the two stepped portions 197b and 197c on the closing sealing member 19 side, is a one stepped portion in the example of FIG.

The two stepped portions 197b and 197c formed on the closing sealing member 19 side both form rectangular surfaces orthogonal to the corresponding cutout portions 196b and 196c. For this reason, as in the case of the joints described with reference to FIGS. 2 to 4, the contact area becomes larger than when flat surfaces without steps are brought into contact with each other, and strong heat welding is performed over a wider range. Since a part is formed, it is excellent in airtightness.

The three-way sealing member 18 and the closed sealing member 19 that constitute the sealing frame 17 are bonded to the solid electrolyte layer 20 by heat welding on the upper and lower surfaces of the members. Here, the upper surface is the upper surface in the stacking direction of the solid battery stack 1 , and the lower surface is the lower surface in the stacking direction of the solid battery stack 1 .

2 to 7, one sealing member of the three-way sealing member and the closed sealing member have a joining structure by heat welding. Therefore, the solid state electric storage device formed of the solid state battery stack 1 having this bonding structure has a high resistance to vibration and the like, and is well suited for use as an electric energy source in moving bodies such as electric vehicles.

FIG. 8 is a diagram showing how the sheet-like members 150a and 150b of the sealing member 15 of FIG. The sheet-like member 150a is a thin sheet-like body made of PP (polypropylene) or PE (polyethylene), and can be thermally welded to the side surface of the solid electrolyte layer 20 disposed above.
The sheet-like member 150b is a thin sheet-like body made of PP (polypropylene) or PE (polyethylene), and can be thermally welded to the side surface of the solid electrolyte layer 20 disposed below.

9 and 10, the solid battery stack 1 has been described with reference to FIG. 1 as well. In the above description, for the sake of convenience, the positive electrode system 30 is stacked under the negative electrode system 10, and the negative electrode system 10 and the positive electrode system 30 are alternately stacked in multiple layers. However, the above description is not intended to define the stacking order of the negative electrode and the positive electrode. The negative electrode system 10 may be stacked under the positive electrode system 30 to stack a plurality of alternating stacks in this form. Alternatively, a positive electrode sandwiched between solid electrolytes and sealed may be laminated on the negative electrode. Alternatively, the negative electrode, the solid electrolyte, and the solid electrolyte and the negative electrode may be stacked in the above order and sealed. A different process is applied to the structure of the bottom and top surfaces of the laminate from that of the periodic structure laminated in the middle.

Next, the effects of the solid-state power storage device of 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 that constitutes a solid power storage device as a comparative example for the embodiment of the present invention. 12 is a partially enlarged view of FIG. 11. FIG. 11 and 12, parts corresponding to those in FIGS. 2 and 3 are given the same reference numerals.

11 and 12, the lower end 191 and upper end 194 of the closure member 19 are flat surfaces, respectively. The flat surface of the lower end portion 191 of the closing sealing member 19 contacts the flat surface of the side surface of the sealing member 15 near the left end portion 151 . Similarly, the flat surface of the upper end 194 of the closing sealing member 19 abuts the flat surface of the side surface near the left end 131 of the sealing member 13 . The closing sealing member 19, the sealing member 15, and the sealing member 13 are joined at these abutted portions. Since the joint surface is flat, the contact area between the two members to be joined is smaller than that in which stepped portions 153 and 133 are formed by notches 152 and 132 as shown in FIGS. In other words, in the embodiment 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 capability is ensured compared to the comparative example. This point is the same for any of the joints in FIGS. 2 to 7, which are embodiments of the present invention.

The solid power storage device of this embodiment has the following effects.
In the solid power storage device of (1), at least one of the three-way sealing member 18 and the closed sealing member 19 has a stepped portion 153 at the contact portion between the two. By joining the three-way sealing member 18 and the closing sealing member 19 at the stepped portion 153, a sufficient contact area is ensured at the joining portion, thereby improving the sealing performance within the sealing frame.

In the solid-state power storage device of (2), the stepped portion 153 is formed by a cutout portion 152 and a stepped portion 153, which are mutually perpendicular contact surfaces formed on at least one of the three-way sealing member 18 and the closed sealing member 19. Therefore, the three-way sealing member 18 and the closed sealing member 19 are joined in close contact with each other at the stepped portion 153, thereby improving the sealing performance at the joining portion of the sealing members.

In the solid power storage device of (3), the stepped portion 153 ensures sufficient sealing performance on the negative electrode side of the solid battery stack 1, which particularly requires sealing performance.

In the solid power storage device of (4), the sheet-like members 150a and 150b provided extending in the stacking direction of the solid battery stack 1 are aligned along the upper surface of the solid electrolyte layer 20, and the sheet-like member 150b is the solid electrolyte. By sticking it along the lower surface of the layer 20, the sealing property in the negative electrode system is improved.

In the solid power storage device of (5), the three-way sealing member 18, the closed sealing member 19, and the solid electrolyte layer 20 are adhered by thermal welding in a contact state, thereby improving the airtightness in the negative electrode system.

In the solid power storage device of (6), by integrating the electrolyte with either the positive electrode or the negative electrode, it becomes possible to manufacture the solid storage battery simply by stacking them, which facilitates manufacturing.

The solid-state power storage device of (7) can provide sufficient durability even when applied to a moving body that requires resistance to vibration.

In the method (8) for manufacturing a solid state electric storage device, since the three-way sealing member 18 and the closed sealing member 19 are joined by heat welding, the sealing performance within 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. Detailed configurations may be changed as appropriate within the scope of the present invention. For example, in the above example, the sheet-like member 150a is provided in a form extending upward from the outer edge of the upper end 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) A sheet-like body of PP or PE, which is the same material as the portion 150), may be arranged at the portion where the sheet-like member 150a is arranged and heat-sealed.

DESCRIPTION OF SYMBOLS 1... Solid battery laminated body 10... Negative electrode system 11... Negative electrode active material layer 12... Negative electrode collector layer 13, 14, 15, 16... Sealing member 17... Sealing frame 18... Three-way sealing member 19... Closure sealing member 20... Solid Electrolyte layer 30 Positive electrode system 31 Positive electrode active material layer 32 Positive electrode current collector layer 150 Sealing member body 150a Sheet member 152 Notch 153 Step

Claims (8)

A positive electrode system in which a positive electrode active material layer is arranged between two facing solid electrolyte layers and a positive electrode current collector layer is arranged in contact with the positive electrode active material layer, and a negative electrode active material layer is arranged in which the negative electrode active material layer is a negative electrode. A solid battery stack in which a negative electrode system in which a current collector layer is arranged in contact is alternately stacked, and a 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 surrounds and seals the inside with four sealing members extending along each side of the outer periphery of the square,
The sealing frame has a three-sided sealing member in which sealing members on three sides along the outer periphery are connected and a closed sealing member arranged to close the open side of the three-sided sealing member,
At least one of the three-way sealing member and the closed sealing member has a stepped portion at the contact portion between the two.
Solid state power storage device. The stepped portion is at least one stepped portion composed of a cutout portion and a stepped portion, which are mutually perpendicular contact surfaces formed on at least one of the three-way sealing member and the closed sealing member. The solid state electric storage device according to claim 1, comprising: 3. The solid state power storage device according to claim 1, wherein said sealing member having said stepped portion is disposed on the negative electrode side of said solid battery stack. At least one of the three-sided sealing member and the closed sealing member includes a sheet-shaped member extending in the stacking direction of the solid battery stack from a sealing member main body portion constituting a part of the sealing frame. The solid-state power storage device according to any one of claims 1 to 3, further comprising: 5. The solid state power storage device according to claim 1, wherein said three-way sealing member and said closed sealing member are configured so that they can be adhered by heat welding with their contact portions in a contact state. 6. The solid state power storage device according to claim 1, wherein an electrolytic solution is sealed in at least one of said positive electrode system and said negative electrode system. 6. The solid state power storage device according to any one of claims 1 to 5, configured to fit a predetermined moving body. 8. A manufacturing method of a solid state electric storage device, wherein the solid state electric storage device according to claim 1 is manufactured by joining the three-way sealing member and the closed sealing member by thermal welding.

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