JP7280906B2 - Secondary battery and manufacturing method thereof - Google Patents

Description

The present technology relates to a secondary battery and a manufacturing method thereof.

For example, in Japanese Unexamined Patent Application Publication No. 2018-163858 (Patent Document 1), in order to provide a prismatic secondary battery that does not easily expand after completion, after injecting an electrolytic solution, part of the gas in the battery case is electrolyzed. It is disclosed to provide a step of discharging the liquid from the liquid injection hole to the outside of the battery case.

JP 2018-163858 A

As in the technique described in Patent Literature 1, when performing the gas discharging step through the electrolyte injection hole, the electrolyte may leak out together with the gas. The electrolyte leaking from the injection hole can reduce the durability of manufacturing equipment such as a gas discharge device. From a different point of view, the amount of electrolyte in the completed secondary battery is not stable, which may affect the performance of the battery. Conventional secondary batteries do not necessarily have a sufficient configuration from the above viewpoint.

An object of the present technology is to provide a secondary battery in which unintended electrolyte leakage is suppressed in a gas discharge process through an electrolyte injection hole, and a method for manufacturing the same.

A secondary battery according to the present technology includes an electrode assembly and a wall portion, and has an outer can housing the electrode assembly, an electrolytic solution stored in the outer can together with the electrode assembly, and an inner surface of the wall of the outer can. and an internal member housed in an outer can. The wall portion is provided with an injection hole for an electrolytic solution, and the injection hole is sealed with a sealing member. Between the wall portion and the internal member, a gap extending along the extending direction of the wall portion and communicating with the injection hole is formed, and at a position facing the gap, at least one of the inner surface of the wall portion and the surface of the internal member. is formed with a recess.

A method for manufacturing a secondary battery according to the present technology is the above-described method for manufacturing a secondary battery, and includes a step of inserting an electrode assembly into an outer can; The method includes a step of injecting an electrolytic solution, a step of discharging gas in the outer can through an injection hole, and a step of sealing the injection hole with a sealing member.

Advantageous Effects of Invention According to the present technology, it is possible to provide a secondary battery in which unintended leakage of electrolyte is suppressed in a gas discharge process through an electrolyte injection hole, and a method of manufacturing the same.

1 is a perspective view of a prismatic secondary battery; FIG. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 1; FIG. 3 is a plan view of a positive electrode plate that constitutes the electrode body; FIG. 3 is a plan view of a negative electrode plate that constitutes the electrode body; FIG. 2 is a plan view showing an electrode body consisting of a positive electrode plate and a negative electrode plate; FIG. 3 is a diagram showing a connection structure between an electrode body, a positive collector member, and a negative collector member. FIG. 4 is a diagram showing a mounting structure of a positive electrode current collecting member and a negative electrode current collecting member to a sealing plate; FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 7; FIG. 8 is a cross-sectional view taken along line IX-IX in FIG. 7; It is a figure which shows the state where the sealing board and the electrode body were connected. 1 is a cross-sectional view schematically showing the structure of a prismatic secondary battery; FIG. FIG. 4 is a plan view showing a state in which an insulating member and a current collecting member are provided on a sealing plate; It is a top view which shows an example of a sealing board. It is a figure which shows an example of the insulating member provided on a sealing board. FIG. 4 is an enlarged cross-sectional view schematically showing an example of the structure of the gap between the sealing plate and the insulating member; FIG. 5 is an enlarged cross-sectional view schematically showing another example of the structure of the gap between the sealing plate and the insulating member; It is a sectional view showing an example of the section shape of a crevice. FIG. 10 is a cross-sectional view showing another example of the cross-sectional shape of the recess; FIG. 10 is a cross-sectional view showing another example of the cross-sectional shape of the recess; FIG. 10 is a plan view showing another example of the planar shape of the recess;

Embodiments of the present technology will be described below. In some cases, the same reference numerals are given to the same or corresponding parts, and the description thereof will not be repeated.

In the embodiments described below, when referring to the number, amount, etc., the scope of the present technology is not necessarily limited to the number, amount, etc., unless otherwise specified. Also, in the following embodiments, each component is not necessarily essential for the present technology unless otherwise specified.

In this specification, the descriptions of "comprise," "include," and "have" are open-ended. That is, when a certain configuration is included, other configurations may or may not be included. In addition, the present technology is not necessarily limited to one that exhibits all of the effects referred to in the present embodiment.

As used herein, "battery" is not limited to lithium-ion batteries, but may include other batteries such as nickel-metal hydride batteries. As used herein, "electrode" may collectively refer to positive and negative electrodes. Also, the term "electrode plate" may collectively refer to a positive electrode plate and a negative electrode plate.

FIG. 1 is a perspective view of a prismatic secondary battery 1. FIG. FIG. 2 is a cross-sectional view taken along line II--II in FIG.

As shown in FIGS. 1 and 2, the prismatic secondary battery 1 includes a battery case 100, an electrode body 200, an insulating sheet 300, a positive electrode terminal 400, a negative electrode terminal 500, a positive current collecting member 600, and a negative electrode. A collector member 700 and a cover member 800 are included.

The battery case 100 is composed of a bottomed prismatic rectangular outer body 110 having an opening and a sealing plate 120 that seals the opening of the rectangular outer body 110 . Rectangular exterior body 110 and sealing plate 120 are preferably made of metal, preferably aluminum or an aluminum alloy.

The sealing plate 120 is provided with an electrolyte injection hole 121 . After the electrolyte is injected into the battery case 100 through the electrolyte injection hole 121 , the electrolyte injection hole 121 is sealed by the sealing member 122 . For example, blind rivets and other metal members can be used as the sealing member 122 .

A gas exhaust valve 123 is provided on the sealing plate 120 . The gas exhaust valve 123 breaks when the pressure inside the battery case 100 exceeds a predetermined value. As a result, the gas inside the battery case 100 is discharged to the outside of the battery case 100 .

The electrode body 200 is accommodated in the battery case 100 together with the electrolyte. The electrode body 200 is formed by stacking a positive electrode plate and a negative electrode plate with a separator interposed therebetween. An insulating sheet 300 made of resin is arranged between the electrode body 200 and the rectangular outer body 110 .

A positive electrode tab 210A and a negative electrode tab 210B are provided at the end of the electrode body 200 on the side of the sealing plate 120 .

The positive electrode tab 210A and the positive electrode terminal 400 are electrically connected via the positive current collecting member 600 . The positive current collector 600 includes a first positive current collector 610 and a second positive current collector 620 . In addition, the positive electrode current collecting member 600 may be composed of one component. The positive electrode current collecting member 600 is preferably made of metal, and more preferably made of aluminum or an aluminum alloy.

The negative electrode tab 210B and the negative electrode terminal 500 are electrically connected via the negative current collecting member 700 . The negative electrode current collector 700 includes a first negative electrode current collector 710 and a second negative electrode current collector 720 . Note that the negative electrode current collecting member 700 may be composed of one component. The negative electrode current collecting member 700 is preferably made of metal, and more preferably made of copper or a copper alloy.

The positive electrode terminal 400 is fixed to the sealing plate 120 via an external insulating member 410 made of resin. The negative electrode terminal 500 is fixed to the sealing plate 120 via an external insulating member 510 made of resin.

The positive electrode terminal 400 is preferably made of metal, and more preferably made of aluminum or an aluminum alloy. The negative electrode terminal 500 is preferably made of metal, and more preferably made of copper or a copper alloy. Negative electrode terminal 500 may have a region made of copper or a copper alloy located inside battery case 100 and a region made of aluminum or an aluminum alloy located outside battery case 100 .

The cover member 800 is positioned between the first positive current collector 610 and the electrode body 200 . The cover member 800 may be provided on the negative electrode current collector side. Also, the cover member 800 is not an essential member and can be omitted as appropriate.

FIG. 3 is a plan view of a positive electrode plate 200A that constitutes the electrode assembly 200. FIG. The positive electrode plate 200A includes a positive electrode active material (for example, lithium-nickel-cobalt-manganese composite oxide, etc.), a binder (polyvinylidene fluoride (PVdF), etc.), and a conductive material ( For example, it has a main body portion 220A on which a positive electrode active material mixture layer containing a carbon material or the like is formed. A positive electrode core protrudes from the edge of the main body, and the protruding positive electrode core constitutes the positive electrode tab 210A. A positive electrode protective layer 230A containing alumina particles, a binder, and a conductive material is provided on a portion of the positive electrode tab 210A adjacent to the body portion 220A. The positive electrode protective layer 230A has an electrical resistance greater than that of the positive electrode active material mixture layer. The positive electrode active material mixture layer may not contain a conductive material. The positive electrode protection layer 230A does not necessarily have to be provided.

FIG. 4 is a plan view of the negative electrode plate 200B that constitutes the electrode body 200. FIG. The negative electrode plate 200B has a main body portion 220B in which negative electrode active material mixture layers are formed on both sides of a negative electrode core made of rectangular copper foil. A negative electrode core protrudes from an end side of the main body portion 220B, and the protruding negative electrode core constitutes the negative electrode tab 210B.

FIG. 5 is a plan view showing an electrode body 200 consisting of a positive electrode plate 200A and a negative electrode plate 200B. As shown in FIG. 5, the electrode body 200 is manufactured so that the positive tabs 210A of each positive plate 200A are laminated at one end, and the negative tabs 210B of each negative plate 200B are laminated. The positive electrode plates 200A and the negative electrode plates 200B are stacked, for example, by about 50 sheets each. The positive electrode plates 200A and the negative electrode plates 200B are alternately laminated with rectangular separators made of polyolefin interposed therebetween. Note that a long separator may be zigzagged and used.

FIG. 6 is a diagram showing a connection structure between the electrode body 200 and the positive current collecting member 600 and the negative current collecting member 700. As shown in FIG. As shown in FIG. 6, the electrode body 200 is composed of a first electrode body element 201 (first lamination group) and a second electrode body element 202 (second lamination group). Separators are also disposed on the outer surfaces of the first electrode element 201 and the second electrode element 202, respectively.

A plurality of positive electrode tabs 210A of the first electrode element 201 constitute a first positive electrode tab group 211A. A plurality of negative electrode tabs 210B of the first electrode element 201 constitute a first negative electrode tab group 211B. A plurality of positive electrode tabs 210A of the second electrode body element 202 constitute a second positive electrode tab group 212A. A plurality of negative electrode tabs 210B of the second electrode element 202 constitute a second negative electrode tab group 212B.

A second positive current collector 620 and a second negative current collector 720 are arranged between the first electrode body element 201 and the second electrode body element 202 . The second positive electrode current collector 620 has a first opening 620A and a second opening 620B. The first positive electrode tab group 211A and the second positive electrode tab group 212A are welded onto the second positive electrode current collector 620 to form the weld connection portion 213 . The first negative electrode tab group 211B and the second negative electrode tab group 212B are welded onto the second negative electrode current collector 720 to form the weld connection portion 213 . Weld connection 213 may be formed, for example, by ultrasonic welding, resistance welding, laser welding, or the like.

7A and 7B are diagrams showing a mounting structure of the positive collector member 600 and the negative collector member 700 to the sealing plate 120. FIG. FIG. 8 shows the VIII-VIII cross section in FIG. FIG. 9 shows the IX-IX section in FIG.

First, with reference to FIGS. 7 and 8, the attachment of the positive collector member 600 to the sealing plate 120 will be described.

An external insulating member 410 made of resin is arranged on the outer surface side of the sealing plate 120 . A first positive electrode current collector 610 and a resin insulating member 630 (positive electrode current collector holder) are arranged on the inner surface side of the sealing plate 120 . Next, the positive electrode terminal 400 is inserted into the through hole of the external insulating member 410 , the positive electrode terminal mounting hole of the sealing plate 120 , the through hole of the first positive electrode current collector 610 , and the through hole of the insulating member 630 . Then, the crimped portion 400A positioned at the tip of the positive electrode terminal 400 is crimped onto the first positive electrode current collector 610 . Thereby, the positive electrode terminal 400, the external insulating member 410, the sealing plate 120, the first positive electrode current collector 610, and the insulating member 630 are fixed. It should be noted that the caulking-connected portions of the positive electrode terminal 400 and the first positive current collector 610 are preferably weld-connected by laser welding or the like. The first positive electrode current collector 610 has a counterbore hole 610A, and the caulking portion 400A is provided in the counterbore hole 610A.

Furthermore, the second positive electrode current collector 620 is arranged on the insulating member 630 such that the second positive electrode current collector 620 partially overlaps the first positive electrode current collector 610 . The second positive electrode current collector 620 is welded to the first positive electrode current collector 610 by laser welding or the like at the first opening 620A provided in the second positive electrode current collector 620 .

As shown in FIG. 8, the insulating member 630 has a tubular portion 630A protruding toward the electrode body 200 side. Cylindrical portion 630</b>A penetrates second opening 620</b>B of second positive electrode current collector 620 and defines hole portion 630</b>B communicating with electrolyte injection hole 121 .

When attaching the positive electrode current collector 600 to the sealing plate 120 , first, the first positive electrode current collector 610 is connected to the insulating member 630 on the sealing plate 120 . Subsequently, the second positive current collector 620 connected to the electrode assembly 200 is attached to the first positive current collector 610 . At this time, the second positive current collector 620 is arranged on the insulating member 630 such that the second positive current collector 620 partially overlaps the first positive current collector 610 . Subsequently, the periphery of the first opening 620A provided in the second positive electrode current collector 620 is weld-connected to the first positive electrode current collector 610 by laser welding or the like.

Next, attachment of the negative electrode current collecting member 700 to the sealing plate 120 will be described with reference to FIGS. 7 and 9. FIG.

An external insulating member 510 made of resin is arranged on the outer surface side of the sealing plate 120 . A first negative electrode current collector 710 and a resin insulating member 730 (negative electrode current collector holder) are arranged on the inner surface side of the sealing plate 120 . Next, the negative terminal 500 is inserted into the through hole of the external insulating member 510 , the negative terminal mounting hole of the sealing plate 120 , the through hole of the first negative current collector 710 , and the through hole of the insulating member 730 . Then, the crimped portion 500A positioned at the tip of the negative electrode terminal 500 is crimped onto the first negative electrode current collector 710 . Thereby, the negative electrode terminal 500, the external insulating member 510, the sealing plate 120, the first negative electrode current collector 710, and the insulating member 730 are fixed. It should be noted that the caulking-connected portions of the negative electrode terminal 500 and the first negative electrode current collector 710 are preferably weld-connected by laser welding or the like.

Furthermore, the second negative electrode current collector 720 is arranged on the insulating member 730 such that a portion of the second negative electrode current collector 720 overlaps with the first negative electrode current collector 710 . The second negative electrode current collector 720 is welded to the first negative electrode current collector 710 by laser welding or the like at the first opening 720A provided in the second negative electrode current collector 720 .

When attaching the negative electrode current collector 700 to the sealing plate 120 , first, the first negative electrode current collector 710 is connected to the insulating member 730 on the sealing plate 120 . Subsequently, the second negative current collector 720 connected to the electrode assembly 200 is attached to the first negative current collector 710 . At this time, the second negative current collector 720 is arranged on the insulating member 730 such that the second negative current collector 720 partially overlaps the first negative current collector 710 . Subsequently, the periphery of the first opening 720A provided in the second negative electrode current collector 720 is welded to the first negative electrode current collector 710 by laser welding or the like.

FIG. 10 is a diagram showing a state in which the sealing plate 120 and the electrode body 200 are connected. As described above, the first electrode body element 201 and the second electrode body element 202 are attached to the sealing plate 120 via the positive electrode current collecting member 600 and the negative electrode current collecting member 700 . Thereby, as shown in FIG. 10, the first electrode body element 201 and the second electrode body element 202 are connected to the sealing plate 120, and the electrode body 200 is electrically connected to the positive electrode terminal 400 and the negative electrode terminal 500. .

From the state shown in FIG. 10, the first electrode body element 201 and the second electrode body element 202 are combined into one. At this time, the first positive electrode tab group 211A and the second positive electrode tab group 212A are bent in different directions. The first negative electrode tab group 211B and the second negative electrode tab group 212B are curved in different directions.

The first electrode body element 201 and the second electrode body element 202 can be put together by tape or the like. Alternatively, the first electrode body element 201 and the second electrode body element 202 can be integrated by arranging them in an insulating sheet molded into a box-like or bag-like shape. Furthermore, the first electrode body element 201 and the second electrode body element 202 can be fixed by adhesion.

The first electrode body element 201 and the second electrode body element 202 combined into one are wrapped with an insulating sheet 300 and inserted into the rectangular outer body 110 . After that, the sealing plate 120 is welded to the rectangular outer body 110 and the opening of the rectangular outer body 110 is sealed with the sealing plate 120 to form the sealed battery case 100 .

After that, a non-aqueous electrolyte is injected into the battery case 100 through an electrolyte injection hole 121 provided in the sealing plate 120 . As the non-aqueous electrolyte, for example, one containing ethylene carbonate (EC), ethylmethyl carbonate (EMC), diethyl carbonate (DEC), and dimethyl carbonate (DMC) is used.

After the non-aqueous electrolyte is injected, the electrolyte injection hole 121 is sealed with a sealing member 122 . The prismatic secondary battery 1 is completed by performing the above steps.

FIG. 11 is a cross-sectional view schematically showing the structure of the prismatic secondary battery 1. As shown in FIG. As shown in FIG. 11, plate-like insulating members 630 and 730 (internal members) are housed in battery case 100 so as to face the inner surface of sealing plate 120 (wall portion) of battery case 100 (external can). . A recess 10 is formed in the inner surface of the sealing plate 120 and a recess 20 is formed in the surface of the insulating member 630 . A gap 30 is formed between the sealing plate 120 and the insulating members 630 and 730 . The recesses 10 and 20 are provided at positions facing the gap 30 .

When manufacturing the prismatic secondary battery 1 , first, the electrode body 200 is inserted into the battery case 100 . Next, an electrolytic solution is injected through the electrolytic solution injection hole 121 into the battery case 100 in which the electrode body 200 is inserted. After that, the gas inside the battery case 100 is discharged through the electrolyte injection hole 121, and the pressure inside the battery case 100 is reduced. At this time, the pressure in battery case 100 is preferably reduced to atmospheric pressure or lower. More preferably, the pressure in battery case 100 is reduced to about atmospheric pressure -0.030 MPa or less, and more preferably, the pressure in battery case 100 is reduced to about atmospheric pressure -0.070 MPa or less. . While the pressure inside the battery case 100 is reduced, the sealing member 122 seals the electrolyte injection hole 121 .

The gap 30 extends along the extending direction of the sealing plate 120 and communicates with the electrolyte injection hole 121 . The gap 30 serves as a gas flow path in the process of discharging the gas to reduce the pressure in the battery case 100 .

When performing the gas discharge process through the electrolyte injection hole 121, the electrolyte can be discharged together with the gas. The electrolyte leaking out from the electrolyte injection hole 121 can reduce the durability of the manufacturing equipment such as the gas discharge device. In addition, the amount of electrolyte in the completed prismatic secondary battery 1 is not stable, which may affect the performance of the battery.

In the present embodiment, recesses 10 and 20 are provided at positions facing gap 30 that serves as a flow path for gas, and recesses 10 and 20 trap electrolyte contained in gas flowing toward electrolyte injection hole 121 ( Therefore, it is possible to suppress leakage of the electrolyte together with the gas from the electrolyte injection hole 121 .

FIG. 12 is a plan view showing a state in which insulating members 630 and 730, a positive collector member 600, and a negative collector member 700 are provided on the sealing plate 120. FIG. 13 is a plan view showing an example of the sealing plate 120, and FIG. 14 is a view showing an example of insulating members 630 and 730 provided on the sealing plate 120. FIG.

As shown in FIGS. 12 to 14, the insulating member 630 has a hole portion 630B (through hole) in a portion facing the electrolyte injection hole 121 of the sealing plate 120. As shown in FIGS. As shown in FIGS. 13 and 14, the recesses 10 and 20 are band-shaped so as to extend in the X-axis direction (second direction) . The recesses 10 and 20 may be formed to extend in the Y-axis direction (first direction) .

In the example shown in FIG. 11, the recess 10 is provided in the sealing plate 120 on the negative electrode side, and the recess 20 is provided in the insulating member 630 on the positive electrode side. A concave portion 10 is formed in the sealing plate 120 and a concave portion 20 is formed in the insulating members 630 and 730 on both the negative electrode sides.

The depth of the recesses 10 and 20 is preferably about 2 mm or less, more preferably about 1 mm or less, and even more preferably about 0.5 mm or less or about 0.1 mm or less. By setting the depth of the recesses 10 and 20 to the above value or less, the effect of trapping the electrolytic solution by the recesses 10 and 20 can be obtained while suppressing the influence on the strength of the sealing plate 120 and the insulating member 630. .

As an example, the thickness of the sealing plate 120 is approximately 2 mm, and the thickness of the insulating members 630 and 730 is approximately 0.6 mm.

The length of the concave portions 10 and 20 along the X-axis direction is preferably about 30 mm or more and 50 mm or less, more preferably about 45 mm or more and 50 mm or less. The length of the concave portions 10 and 20 along the Y-axis direction is preferably about 15 mm or more and 25 mm or less, more preferably about 20 mm or more and 25 mm or less. The length of the recesses 10, 20 along the Y-axis direction is preferably about 30% or more of the length of the recesses 10, 20 along the X-axis direction.

As an example, the length of the sealing plate 120 along the X-axis direction is about 150 mm, and the length of the sealing plate 120 along the Y-axis direction is about 25 mm.

FIG. 15 is an enlarged cross-sectional view schematically showing an example of the structure of the gap between the sealing plate and the insulating member, and FIG. 16 is an enlarged cross-sectional view schematically showing a modification thereof. In the example shown in FIG. 15, the recess 10 is formed in the inner surface of the sealing plate 120 facing the insulating member 730, and in the example shown in FIG. there is

The height (H) of the gap 30 along the Z-axis direction is preferably approximately 2 mm or less, more preferably 1 mm or less, and even more preferably approximately 0.5 mm or less.

The area of the gap 30 when viewed in the Z-axis direction is preferably about 5 cm ² or more, more preferably about 15 cm ² or more and 40 cm ² or less, and even more preferably about 35 cm ² or more and 40 cm ² or less.

The length of the gap 30 is preferably about 20 mm or longer, more preferably about 30 mm or longer, or about 50 mm or longer. More preferably, the length of the gap 30 along the X-axis direction (longitudinal direction) is about 110 mm or more and 150 mm or less, or about 140 mm or more and 150 mm or less, and the length of the gap 30 along the Y-axis direction (lateral direction) is about The length of is about 10 mm or more and 30 mm or less, or about 20 mm or more and 30 mm or less.

By setting the height and planar dimension (area) of the gap 30 within the ranges described above, the effect of trapping the electrolytic solution by the concave portions 10 and 20 can be improved.

17 to 20 are cross-sectional views showing modifications of the cross-sectional shapes of the recesses 10 and 20. FIG. In the example of FIG. 17, recesses 10 and recesses 20 are alternately formed in the X-axis direction. In the example of FIG. 18, the concave portion 10 and the concave portion 20 extending in the X-axis direction are formed so as to face each other. In the example of FIG. 19, the uneven portion 11 is formed on the bottom surface of the concave portion 10 extending in the X-axis direction. In either example, turbulence is likely to occur in the gas flowing through the gap 30, and the effect of trapping the electrolytic solution by the concave portions 10 and 20 can be enhanced.

In the example of FIG. 20 , a circular concave portion 10 is formed in the sealing plate 120 so as to surround the electrolyte injection hole 121 . By doing so, it is possible to obtain the effect of trapping the electrolyte around the electrolyte injection hole 121, and to effectively suppress the unintended leakage of the electrolyte.

In the present technology, the form of the "electrode body" is not particularly limited, and may be a wound electrode body or a laminated electrode body. When a laminated electrode body is used, the separator may be a sheet type separator, or may be a folded or wound type separator.

In the present technology, the type of "electrolyte" is not particularly limited. A non-aqueous electrolyte containing a salt and a non-aqueous solvent can be used as a preferred "electrolyte".

In the present technology, the "electrolyte injection hole" may be provided in the "sealing plate", or may be provided in another wall surface of the "armored can".

In the present technology, it is preferable that the "internal member" as the "flow path forming member" that forms a gap serving as a gas flow path together with the "wall portion" of the "armored can" be composed of an "insulating member." Typically, it is composed of a "resin member". The material of the "resin member" is not particularly limited. As examples, PP (polypropylene), PPS (polyphenylene sulfide), PFA (perfluoroalkoxyalkane), etc. can be used.

In the present technology, it is preferable that the edges of the “recessed portion” have a stepped, angular shape as in the above-described examples, instead of a sloped shape. By doing so, it is possible to easily trap the electrolytic solution in the concave portion.

Although the embodiments of the present technology have been described above, the embodiments disclosed this time should be considered as examples and not restrictive in all respects. The scope of the present technology is indicated by the scope of claims, and is intended to include all modifications within the meaning and scope of equivalence to the scope of the claims.

1 prismatic secondary battery, 10 recessed portion, 11 uneven portion, 20 recessed portion, 30 gap, 100 battery case, 110 prismatic exterior body, 120 sealing plate, 121 electrolyte injection hole, 122 sealing member, 123 gas discharge valve, 200 Electrode body 200A positive electrode plate 200B negative electrode plate 201 first electrode body element 202 second electrode body element 210A positive electrode tab 210B negative electrode tab 211A first positive electrode tab group 211B first negative electrode tab group 212A second Positive electrode tab group 212B Second negative electrode tab group 213 Welded connection portion 220A, 220B Body portion 230A Positive electrode protective layer 300 Insulating sheet 400 Positive electrode terminal 400A Crimped portion 410 External side insulating member 500 Negative electrode terminal 500A Crimped portion 510 External side insulating member 600 Positive electrode collector 610 First positive collector 610A Counterbore 620 Second positive collector 620A First opening 620B Second opening 630 Insulating member 630A Cylindrical part 630B Hole 700 Negative collector 710 First negative collector 720 Second negative collector 720A First opening 730 Insulating member 800 Cover member.

Claims (11)

an electrode body;
an outer can containing a wall portion and housing the electrode body;
an electrolytic solution housed in the outer can together with the electrode body;
an internal member housed in the outer can so as to face the inner surface of the wall of the outer can,
The wall portion is provided with an injection hole for the electrolytic solution,
The injection hole is sealed with a sealing member,
A gap extending along the extending direction of the wall portion and communicating with the injection hole is formed between the wall portion and the internal member,
a recess is formed in at least one of the inner surface of the wall portion and the surface of the internal member at a position facing the gap ;
The internal member has a through hole in a portion facing the injection hole,
The wall portion has a substantially rectangular planar shape including short sides and long sides,
The concave portion has a strip-shaped portion extending in a first direction along the short side or a second direction along the long side. secondary battery. The outer can includes a main body having an opening and a sealing plate that seals the opening of the main body,
2. The secondary battery according to claim 1, wherein said wall portion is configured by said sealing plate. 3. The secondary battery according to claim 1, wherein said internal member is composed of a plate-shaped insulating member. 4. The secondary battery according to any one of claims 1 to 3 , wherein the height of said gap along the direction orthogonal to the extending direction of said wall is 2 mm or less. 5. The secondary battery according to any one of claims 1 to 4 , wherein said gap has an area of 5 cm<2> or more when viewed in a direction orthogonal to the extending direction of said wall. The secondary battery according to any one of claims 1 to 5, wherein the recess has a depth of 2 mm or less. The secondary battery according to any one of claims 1 to 6 , wherein the length of the recess along the first direction is 30% or more of the length of the recess along the second direction. an electrode body having an electrode tab;
a collector member electrically connected to the electrode tab;
an outer can containing a wall portion and housing the electrode body and the current collecting member;
an electrolytic solution housed in the outer can together with the electrode body and the current collecting member;
an internal member housed in the outer can so as to face the inner surface of the wall of the outer can,
The wall portion is provided with an injection hole for the electrolytic solution,
The injection hole is sealed with a sealing member,
A gap extending along the extending direction of the wall portion and communicating with the injection hole is formed between the wall portion and the internal member,
a recess is formed in at least one of the inner surface of the wall portion and the surface of the internal member at a position facing the gap;
The secondary battery, wherein the internal member is provided between the wall portion and the current collecting member, and is composed of an insulating member that electrically insulates the wall portion from the current collecting member. 9. The secondary battery according to claim 8, wherein said internal member has a through hole in a portion facing said injection hole. A method for manufacturing a secondary battery according to any one of claims 1 to 9,
a step of inserting the electrode assembly into the outer can;
a step of injecting the electrolytic solution through the injection hole into the outer can into which the electrode assembly is inserted;
a step of discharging the gas in the outer can through the liquid injection hole;
and sealing the liquid injection hole with the sealing member. 11. The method of manufacturing a secondary battery according to claim 10, wherein in the step of sealing said liquid injection hole with said sealing member, the pressure inside said outer can is equal to or lower than atmospheric pressure.

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