Electricity storage unit and method for manufacturing electricity storage unit

Abstract

The invention relates to a power storage cell and a method for manufacturing the power storage cell. An electricity storage cell is provided with: a pair of electrode bodies each having an electrode tab and disposed so as to face each other; an intermediate member that is formed of an insulating material and is disposed between the electrode tabs of the pair of electrode bodies; a laminated exterior body that accommodates the pair of electrode bodies and the interposer member; a conductive film provided on the surface of the interposing member and connected to each of the electrode tabs; and a current collection terminal connected to the conductive film and protruding from the laminated exterior body.

Description

Technical Field

[0001] The present disclosure relates to a power storage unit and a method for manufacturing the power storage unit. Background Art

[0002] For example, in Japanese Patent Publication No. 2023-525907, a battery having a plurality of electrode body assemblies and a shell for accommodating the plurality of electrode body assemblies is disclosed. Each electrode body assembly includes a pair of electrode bodies adjacent to each other (adjacent), an insulating spacer, a tab support member formed into a square cylindrical shape, an electrode lead-out member, and a sealing film. Each electrode body has an electrode body main body and a tab. The insulating spacer is arranged between a pair of adjacent tabs. The insulating spacer is fixed to the third surface of the tab support member. The tab is connected to the first surface of the tab support member. The electrode lead-out member is connected to the fourth surface of the tab support member and protrudes from the sealing film. Summary of the Invention

[0003] In the battery described in Japanese Patent Publication No. 2023-525907, the structure for leading the electrode lead-out member to the outside of the sealing film is complicated.

[0004] An object of the present disclosure is to provide an electricity storage unit and a method for manufacturing the electricity storage unit that can reduce the number of components.

[0005] According to one aspect of the present disclosure, a storage unit comprises: a pair of electrode bodies, each having an electrode tab, arranged in a mutually opposing manner; an interposing member, made of an insulating material, arranged between the electrode tabs of the pair of electrode bodies; a laminated outer body, accommodating the pair of electrode bodies and the interposing member; a conductive film, arranged on the surface of the interposing member, connected to the electrode tabs; and a collector terminal, which is connected to the conductive film and protrudes from the laminated outer body.

[0006] The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 This is a perspective view schematically showing an electric storage unit in one embodiment of the present disclosure.

[0008] Figure 2 yes Figure 1 An exploded perspective view of the power storage unit shown.

[0009] Figure 3 This is an exploded perspective view of the power storage unit.

[0010] Figure 4 This is a front view of the power storage unit.

[0011] Figure 5 yes Figure 4 Cross-sectional view at line VV in FIG.

[0012] Figure 6 yes Figure 4 Cross-sectional view at line VI-VI in FIG.

[0013] Figure 7 It is a cross-sectional view schematically showing a method for manufacturing an intervening member and a conductive film.

[0014] Figure 8 It is a cross-sectional view schematically showing a modified example of the intervening member.

[0015] Figure 9 It is a cross-sectional view schematically showing a modified example of the conductive film and the current collecting terminal.

[0016] Figure 10 It is a cross-sectional view schematically showing a modified example of the method for manufacturing an intervening member and a conductive film.

[0017] Figure 11 It is a cross-sectional view schematically showing a modified example of the power storage cell unit. DETAILED DESCRIPTION

[0018] The embodiments of the present disclosure will be described with reference to the accompanying drawings. In the drawings referred to below, the same or corresponding components are denoted by the same reference numerals.

[0019] Figure 1 This is a perspective view schematically showing a power storage unit in one embodiment of the present disclosure. Figure 2 yes Figure 1 An exploded perspective view of the power storage unit shown. Figure 3 This is an exploded perspective view of the power storage unit. Figure 4 This is a front view of the power storage unit. Figure 5 yes Figure 4 Cross-sectional view at line VV in FIG. Figure 6 yes Figure 4 This power storage unit 1 is mounted on the bottom of a vehicle, for example.

[0020] like Figures 1 to 6 As shown, the electric storage unit 1 includes a plurality of electric storage unit units 100 and a covering sheet 200 (see Figure 5 as well as Figure 6 ), the battery cell housing 300, and the external terminal 400. Figure 2 In the figure, the covering sheet 200 is omitted.

[0021] The plurality of storage cell units 100 include a first storage cell unit 101, a second storage cell unit 102, a third storage cell unit 103, and a fourth storage cell unit 104. In this embodiment, the plurality of storage cell units 100 include eight storage cell units 100. However, the number of storage cell units 100 is not limited to eight. Examples of each storage cell unit 100 include lithium-ion batteries. Alternatively, each storage cell unit 100 may be formed of a so-called all-solid-state battery containing a solid electrolyte.

[0022] First storage cell unit 101 is connected to second storage cell unit 102. Third storage cell unit 103 is connected to fourth storage cell unit 104. First storage cell unit 101 and third storage cell unit 103 are adjacent to each other in a second direction perpendicular to both the first direction in which first storage cell unit 101 and second storage cell unit 102 are arranged and the vertical direction. Second storage cell unit 102 and fourth storage cell unit 104 are adjacent to each other in the second direction. Each storage cell unit 100 has a shape that is longer in the first direction than in the second direction and that extends longer in the first direction than in the vertical direction. Each storage cell unit 100 has a shape that extends longer in the vertical direction than in the second direction.

[0023] Figure 3 1 is an exploded perspective view of a storage cell unit 100. Each storage cell unit 100 includes at least one electrode body 110, an intervening member 120, a conductive film 130, a current collecting terminal 140, a cover 150, and a laminated outer body 160. Figure 3 In FIG, the laminated outer casing 160 is omitted. Figure 2 In FIG, the laminated outer casing 160 of the second power storage cell unit 102 and the laminated outer casing 160 of the fourth power storage cell unit 104 are omitted.

[0024] At least one electrode body 110 includes two electrode bodies 110. However, the number of electrode bodies 110 is not limited to two. Each electrode body 110 is composed of a wound body in which a positive electrode sheet and a negative electrode sheet are wound with a separator interposed therebetween. However, each electrode body 110 may also be composed of a stacked body in which a positive electrode sheet and a negative electrode sheet are stacked with a separator interposed therebetween. The two electrode bodies 110 are stacked in the stacking direction ( Figure 5 Each electrode body 110 is formed to be elongated in a direction perpendicular to both the stacking direction and the vertical direction. The stacking direction (thickness direction) corresponds to the second direction, and the perpendicular direction corresponds to the first direction.

[0025] Each electrode body 110 has a coated portion 112 and an electrode tab 114. The coated portion 112 is the area of ​​the electrode foil of the positive or negative electrode sheet where the active material layer is applied. The electrode tab 114 is the area of ​​the electrode foil of the positive or negative electrode sheet where the active material layer is not applied, that is, the uncoated portion of the electrode foil where the active material layer is exposed. The electrode tab 114 protrudes orthogonally from the coated portion 112. A pair of electrode tabs 114 facing each other in the stacking direction have the same polarity.

[0026] The interposing member 120 is disposed between a pair of electrode tabs 114 adjacent to each other in the stacking direction. The interposing member 120 is made of an insulating material (synthetic resin, etc.). Figure 3 as well as Figure 5 As shown, the intervening member 120 includes a spacer portion 122 and a support portion 124 .

[0027] The spacer 122 is adjacent to the boundary of a pair of adjacent coated portions 112 in the orthogonal direction, and is adjacent to a pair of adjacent electrode tabs 114 in the stacking direction. The spacer 122 has a shape whose dimension in the stacking direction gradually increases as it moves away from the boundary of the pair of coated portions 112 in the orthogonal direction. The spacer 122 is formed in a generally triangular prism shape.

[0028] The support portion 124 supports each electrode tab 114. The support portion 124 protrudes outward in a direction perpendicular to the spacer 122. The support portion 124 is formed integrally with the spacer 122 from the same material as the spacer 122. The support portion 124 is formed in a substantially quadrangular prism shape.

[0029] The conductive film 130 is made of metal (copper, aluminum, etc.) and is provided on the surface of the interposing member 120. The conductive film 130 is connected to each electrode tab 114. The conductive film 130 includes a pair of connection bases 132 and a connecting portion 134.

[0030] Each connection base 132 is a portion connected to the electrode tab 114. Each connection base 132 is provided between the support portion 124 and the electrode tab 114. Each connection base 132 covers the outer side surface of the support portion 124 in the stacking direction.

[0031] The connecting portion 134 connects the pair of connecting bases 132. The connecting portion 134 covers the outer side surface of the support portion 124 in the orthogonal direction. The thickness of the connecting portion 134 may be the same as or different from the thickness of each connecting base 132.

[0032] The current collector terminal 140 is connected to the conductive film 130. The current collector terminal 140, which is electrically connected to the positive electrode tab 114 via the conductive film 130, is made of, for example, aluminum. The current collector terminal 140, which is electrically connected to the negative electrode tab 114 via the conductive film 130, is made of, for example, copper. The current collector terminal 140 includes a connecting portion 142 and a protruding portion 144.

[0033] The connection portion 142 is connected to the coupling portion 134 by welding or the like. The connection portion 142 is formed in a flat plate shape. The thickness of the connection portion 142 may be greater than the thickness of the conductive film 130 .

[0034] The protrusion 144 protrudes outward in an orthogonal direction from the connection portion 142. The protrusion 144 is formed in a flat plate shape. The thickness of the protrusion 144 may be greater than the thickness of the conductive film 130. Figure 5 As shown, the protrusion 144 of the collector terminal 140 in the first storage cell unit 101 is connected to the protrusion 144 of the collector terminal 140 in the second storage cell unit 102. Similarly, the protrusion 144 of the collector terminal 140 in the third storage cell unit 103 is connected to the protrusion 144 of the collector terminal 140 in the fourth storage cell unit 104.

[0035] like Figure 5 As shown, an insulating member 500 may be disposed between the connection between the protrusion 144 of the first storage cell unit 101 and the protrusion 144 of the second storage cell unit 102 and the connection between the protrusion 144 of the third storage cell unit 103 and the protrusion 144 of the fourth storage cell unit 104 .

[0036] The cover 150 covers the end of the electrode body 110 in the orthogonal direction, more specifically, covers the electrode tab 114. The cover 150 is made of an insulating material (synthetic resin, etc.). Figure 2 、 Figure 3 as well as Figure 5 As shown, the cover 150 is provided with a through hole h through which the protrusion 144 is inserted.

[0037] The laminated outer package 160 houses the electrode bodies 110, the intervening member 120, the conductive film 130, a portion of the current collecting terminal 140, and the cover 150. The laminated outer package 160 is made of a laminated film. Figure 5 As shown, the laminated outer case 160 has an edge portion 162. The edge portion 162 is formed by connecting (welding) laminate films to each other. The protrusion 144 protrudes outward in the orthogonal direction from the edge portion 162 of the laminated outer case 160.

[0038] Covering sheet 200 (refer to Figure 5 as well as Figure 6) covers the plurality of storage cell units 100. More specifically, the covering sheet 200 covers the plurality of storage cell units 100 so as to surround the plurality of storage cell units 100. The covering sheet 200 is made of an insulating material (synthetic resin, etc.).

[0039] The battery cell case 300 houses a plurality of battery cell units 100 and a cover sheet 200. The battery cell case 300 is made of, for example, aluminum. The battery cell case 300 is formed into a rectangular parallelepiped shape that is long in the first direction. Figure 1 as well as Figure 2 As shown, the power storage unit case 300 includes a case body 310 and a cover 320 .

[0040] The case body 310 is formed in a rectangular tube shape that is long in the first direction and surrounds the plurality of storage battery cells 100 and the covering sheet 200 .

[0041] The cover 320 is connected to the case body 310 by welding or the like so as to close the opening of the case body 310 .

[0042] The external terminal 400 is provided on the cover 320 . The external terminal 400 is connected to the collector terminal 140 of the electric storage cell unit 100 that is arranged closest to the cover 320 among the plurality of electric storage cell units 100 .

[0043] Next, refer to Figure 7 The following describes a method for manufacturing the intervening member 120 and the conductive film 130. The intervening member 120 and the conductive film 130 are integrally formed by insert molding. Specifically, the manufacturing method includes a preparation step, a placement step, and a filling step.

[0044] In the preparation step, a first mold 10 and a second mold 20 are prepared. The first mold 10 has a supply port 10a for supplying the insulating material forming the intervening member 120 to the space S. The first mold 10 can be contacted and separated from each other and have a space S corresponding to the intervening member 120 when in contact with each other.

[0045] In the placement step, the conductive film 130 is placed in the second mold 20 .

[0046] In the filling step, with the conductive film 130 disposed in the second mold 20 , the insulating material forming the intervening member 120 is filled into the space S, thereby integrally forming the conductive film 130 and the intervening member 120 .

[0047] As described above, in the electricity storage cell 1 of the present embodiment, the electrode tab 114 and the current collector terminal 140 are electrically connected via the conductive film 130 provided on the surface of the intervening member 120 , thereby simplifying the lead-out structure of the current collector terminal 140 .

[0048] Hereinafter, modifications of the above-described embodiment will be described.

[0049] <First Modification>

[0050] like Figure 8 As shown, the intervening member 120 may include a covering portion 126 . The covering portion 126 covers the edge of the connection base 132 . The covering portion 126 is provided at a boundary between the spacer 122 and the support portion 124 .

[0051] In this aspect, it is possible to suppress the connection base 132 from being peeled off from the support portion 124 .

[0052] <Second Modification>

[0053] like Figure 9 As shown, the collector terminal 140 may be formed integrally with the conductive film 130 using the same material as the conductive film 130 .

[0054] In this case, if Figure 10 As shown, the second mold 20 may include a first split mold 21 and a second split mold 22 that can be separated from each other.

[0055] In this embodiment, compared to a case where the collector terminal 140 is formed of a member different from the conductive film 130 , separation of the collector terminal 140 from the conductive film 130 can be suppressed.

[0056] <Third Modification>

[0057] like Figure 11 As shown, the cover 150 can be omitted. In this example, the laminated outer body 160 is in contact with the connecting portion 134.

[0058] Those skilled in the art will understand that the above-described exemplary embodiments are specific examples of the following aspects.

[0059] [Scheme 1]

[0060] A power storage unit comprising:

[0061] a pair of electrode bodies, each having an electrode tab, arranged to face each other;

[0062] an interposing member, made of an insulating material, and disposed between the electrode tabs of the pair of electrode bodies;

[0063] a laminated outer package housing the pair of electrode bodies and the intervening member;

[0064] a conductive film, disposed on a surface of the intervening member and connected to each of the electrode tabs; and

[0065] A current collecting terminal is connected to the conductive film and protrudes from the laminated outer package.

[0066] In this electricity storage cell, the electrode tab and the current collecting terminal are electrically connected via the conductive film provided on the surface of the intervening member, and thus the number of components can be reduced.

[0067] [Scheme 2]

[0068] According to the power storage unit of claim 1,

[0069] The current collecting terminal is formed integrally with the conductive film using the same material as that of the conductive film.

[0070] In this embodiment, the current collecting terminal can be prevented from peeling off from the conductive film, compared to a case where the current collecting terminal is formed of a member different from the conductive film. Furthermore, the step of connecting the current collecting terminal to the conductive film can be omitted.

[0071] [Scheme 3]

[0072] According to the power storage unit of claim 1,

[0073] Each of the electrode bodies further includes an electrode foil and a coating portion of an active material layer provided on the electrode foil.

[0074] Each of the electrode tabs protrudes from the coating portion in a direction perpendicular to the stacking direction in which the pair of electrode bodies face each other.

[0075] The pair of electrode tabs facing each other in the stacking direction have the same polarity.

[0076] The intervening member has:

[0077] a spacer portion adjacent to a boundary portion of a pair of the coating portions adjacent to each other in the orthogonal direction and adjacent to a pair of the electrode tabs adjacent to each other in the stacking direction; and

[0078] A support portion protrudes outward from the spacer in the orthogonal direction to support each of the electrode tabs.

[0079] The spacer has a shape in which a dimension in the stacking direction gradually increases as it moves away from the boundary between a pair of adjacent application portions in the orthogonal direction.

[0080] In this embodiment, the distance between a pair of adjacent electrode tabs is maintained by the spacer, and each electrode tab is effectively supported by the support portion. Furthermore, breakage of the electrode tab due to contact between the spacer and the electrode tab can be suppressed.

[0081] [Scheme 4]

[0082] According to the power storage unit of claim 3,

[0083] The conductive film has:

[0084] a pair of connection bases covering outer side surfaces of the support portion in the stacking direction and connected to the electrode tabs; and

[0085] a connecting portion covering the outer side surface of the support portion in the orthogonal direction and connecting the pair of connecting bases to each other;

[0086] The current collecting terminal is connected to the connecting portion.

[0087] [Scheme 5]

[0088] According to the power storage unit of claim 4,

[0089] The intervening member includes a covering portion that covers an edge portion of the connecting base.

[0090] In this aspect, it is possible to suppress the separation of the connection base from the support portion.

[0091] [Scheme 6]

[0092] A method for manufacturing a power storage unit is the method for manufacturing a power storage unit according to any one of claims 1 to 5.

[0093] The method for manufacturing the power storage unit comprises:

[0094] an arranging step of arranging the conductive film in a first mold and a second mold that are capable of contacting and separating from each other and have a space corresponding to the intervening member when in contact with each other; and

[0095] A filling step in which the conductive film and the intervening member are integrally formed by filling the space with an insulating material forming the intervening member while the conductive film is arranged in the first mold and the second mold.

[0096] While the embodiments of the present invention have been described, the embodiments disclosed herein are to be construed as illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, and is intended to encompass all modifications within the meaning and scope of the claims and equivalents thereof.

Claims

1. A power storage unit comprising: a pair of electrode bodies, each having an electrode tab and arranged to face each other; an interposing member, made of an insulating material, and disposed between the electrode tabs of the pair of electrode bodies; a laminated outer package housing the pair of electrode bodies and the intervening member; A conductive film is provided on the surface of the interposing member and is connected to each of the electrode tabs; as well as A current collecting terminal is connected to the conductive film and protrudes from the laminated outer package.

2. The power storage unit according to claim 1, The collector terminal is formed integrally with the conductive film using the same material as that of the conductive film.

3. The power storage unit according to claim 1, Each of the electrode bodies further includes an electrode foil and a coating portion of an active material layer provided on the electrode foil. Each of the electrode tabs protrudes from the coating portion in a direction perpendicular to the stacking direction in which the pair of electrode bodies face each other. The pair of electrode tabs facing each other in the stacking direction have the same polarity. The intervening member has: a spacer portion adjacent to a boundary portion of a pair of the coating portions adjacent to each other in the orthogonal direction and adjacent to a pair of the electrode tabs adjacent to each other in the stacking direction; and a supporting portion protruding outward from the spacer in the orthogonal direction and supporting each of the electrode tabs; The spacer has a shape in which a dimension in the stacking direction gradually increases as it moves away from the boundary between a pair of adjacent application portions in the orthogonal direction.

4. The power storage unit according to claim 3, The conductive film has: a pair of connection bases covering outer side surfaces of the support portion in the stacking direction and connected to the electrode tabs; and a connecting portion covering the outer side surface of the support portion in the orthogonal direction and connecting the pair of connecting bases to each other, The current collecting terminal is connected to the connecting portion.

5. The power storage unit according to claim 4, The intervening member includes a covering portion that covers an edge portion of the connecting base.

6. A method for manufacturing a storage battery cell, the method for manufacturing a storage battery cell according to claim 1, The method for manufacturing the power storage unit comprises: an arranging step of arranging the conductive film in a first mold and a second mold that are capable of contacting and separating from each other and have a space corresponding to the intervening member when in contact with each other; and A filling step in which the conductive film and the intervening member are integrally formed by filling the space with an insulating material forming the intervening member while the conductive film is arranged in the first mold and the second mold.

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