Battery

Abstract

To provide a battery that regulates the movement of an electrode body and prevents damages to the electrode body.SOLUTION: A battery 100 includes: an electrode body 20 having a positive electrode and a negative electrode; an outer casing 12 that has a bottom part, an open part 12u, and a side wall 12b and houses the electrode body 20; a sealing plate 14 that seals an open part 12u; a collector 35 that is electrically connected with the positive electrode and the negative electrode; a terminal 6 that is electrically connected to the collector 35 and is attached to the sealing plate 14; and a resin insulation member 80 that insulates the collector 35 and at least a part of the sealing plate 14 at at least any one of the positive electrode and the negative electrode. Here, the resin insulation member 80 is integrally formed with at least a part of the collector 35, and at least a part of region is arranged at a position 81 that is opposite to the electrode body 20 between the collector 35 and the side wall 12b in a vertical direction Z directed to the bottom part of the outer casing 12 from the sealing plate 14.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present disclosure relates to a battery.

Background Art

[0002] In recent years, batteries such as lithium-ion secondary batteries have been suitably used as portable power sources for personal computers, mobile terminals, etc., and power sources for driving vehicles such as battery electric vehicles (BEVs), hybrid electric vehicles (HEVs), and plug-in hybrid electric vehicles (PHEVs). Conventionally, a battery having such applications includes an electrode body having a positive electrode and a negative electrode, an exterior body that houses the electrode body, a sealing plate, a current collector electrically connected to the positive electrode or the negative electrode, a terminal electrically connected to the current collector, and a resin insulating member. Patent Document 1 discloses a battery including a protruding portion that protrudes from the side of the sealing plate toward the side of the electrode body and an insulating member.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, when using a battery for the above-mentioned applications, vibration, shock, etc. may be applied to the battery from the outside. As a result of intensive studies by the present inventor, it has been found that there is room for improvement in the battery disclosed in Patent Document 1 from the viewpoint of vibration resistance. More specifically, in a battery having such a configuration, a gap is generated between the electrode body and the current collector. In other words, the degree of freedom of the electrode body becomes high in the horizontal direction (lateral direction). Therefore, when the electrode body moves horizontally within the exterior body due to an external force such as a vibration load, there is a risk of inconvenience such as damage to the electrode body.

[0005] The object of the technology disclosed herein is made in view of the above circumstances, and it is to provide a battery that restricts the movement of the electrode body and prevents damage to the electrode body.

Means for Solving the Problems

[0006] The battery disclosed herein includes an electrode body having a positive electrode and a negative electrode, a bottom portion, an opening facing the bottom portion, and a side wall extending from an end of the bottom portion toward the opening, and an exterior body that houses the electrode body; a sealing plate having a terminal hole and sealing the opening; a current collector disposed within the exterior body and electrically connected to the positive electrode or the negative electrode; a terminal that is electrically connected to the current collector within the exterior body, is inserted through the terminal hole, and is attached to the sealing plate; and a resin insulating member that insulates at least one of the positive electrode or the negative electrode from at least a part of the current collector and at least a part of the sealing plate. Here, the resin insulating member is integrally formed with at least a part of the current collector. And at least a part of the resin insulating member is disposed at a position facing the electrode body between the current collector and the side wall in a vertical direction from the sealing plate toward the bottom portion of the exterior body.

[0007] According to such a configuration, the resin insulating member is integrally formed with at least a part of the current collector. Thereby, the number of parts is reduced, and it is possible to reduce the man-hours for assembling the battery. And at least a part of the resin insulating member is disposed at a position facing the electrode body between the current collector and the side wall in a vertical direction from the sealing plate toward the bottom portion of the exterior body. According to this, the gap between the electrode body and the current collector is reduced by the resin insulating member. Therefore, the movement of the electrode body in the horizontal direction (also referred to as the lateral direction or the width direction of the exterior body) is restricted, and the reliability of the vibration resistance of the electrode body is improved. Thus, damage to the electrode body can be prevented.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments according to the technology disclosed herein will be described with reference to the drawings. Note that matters not mentioned in this specification and necessary for implementing the technology disclosed herein can be grasped as design matters of those skilled in the art based on the prior art in the relevant field. The technology disclosed herein can be implemented based on the content disclosed in this specification and the common general knowledge in the relevant field. Also, in the following drawings, members and parts having the same function are denoted by the same reference numerals for explanation. Also, the dimensional relationships (length, width, thickness, etc.) in each figure do not reflect the actual dimensional relationships. In this specification, the numerical range expressed as "A to B" includes A and B, and also includes the meaning of "preferably greater than A" and "preferably less than B".

[0010] Note that in this specification, the term "battery" refers to all power storage devices capable of extracting electrical energy, and is a concept including primary batteries and secondary batteries. Also, in this specification, the term "secondary battery" refers to all power storage devices capable of repeated charge and discharge, and is a concept including so-called storage batteries (chemical batteries) such as lithium ion secondary batteries and nickel metal hydride batteries.

[0011] FIG. 1 is a perspective view schematically showing a battery 100 according to an embodiment. FIG. 2 is a schematic longitudinal sectional view taken along line II-II in FIG. 1. FIG. 3 is a schematic longitudinal sectional view taken along line III-III in FIG. 2. In the following description, the reference signs L, R, F, Rr, U, and D in the drawings represent left, right, front, rear, upper, and lower, respectively. Also, the reference sign X in the drawings indicates the short side direction of the battery 100, the reference sign Y indicates the long side direction (also referred to as the lateral direction or the horizontal direction) of the battery 100, and the reference sign Z indicates the vertical direction (also referred to as the longitudinal direction or the height direction) of the battery 100. However, these are merely directions for convenience of explanation and do not limit the installation form of the battery 100 in any way.

[0012] <Battery 100> As shown in FIGS. 1 and 2, the battery 100 includes a battery case 1, an electrode body 20, a positive electrode terminal 6, a negative electrode terminal 8, a positive electrode current collector 35, a negative electrode current collector 45, and a resin insulating member 80. Although not shown in the drawings, the battery 100 further includes an electrolytic solution here. The battery 100 is characterized by including the resin insulating member 80 disclosed herein, and the other configurations may be the same as those in the prior art. Here, the battery 100 is a non-aqueous electrolyte secondary battery.

[0013] As shown in FIG. 1 or 2, the battery case 1 includes an exterior body 12 having an opening 12u portion and a sealing plate 14 that seals the opening 12u. As shown in FIG. 1, the battery case 1 has a flat and bottomed rectangular parallelepiped (rectangular) outer shape here. The material of the battery case 1 (the exterior body 12 and the sealing plate 14) may be the same as those conventionally used, and is formed of, for example, aluminum or an aluminum alloy. The exterior body 12 and the sealing plate 14 have sizes corresponding to the number of electrode bodies 20 to be accommodated (one or more, here, a plurality) and the size and the like.

[0014] The exterior body 12 is a housing that houses the electrode body 20 and the electrolytic solution. The exterior body 12 is a bottomed and rectangular container having an opening 12u on its upper surface. As shown in FIG. 1, the exterior body 12 includes a bottom 12d, a pair of long side walls 12a that extend upward from the long sides of the bottom 12d and face each other, and a pair of short side walls 12b that extend upward from the short sides of the bottom 12d and face each other. The bottom 12d is substantially rectangular. The opening 12u faces the bottom 12d. The long side walls 12a and the short side walls 12b are examples of side walls in the technology disclosed herein.

[0015] The sealing plate 14 is a planar substantially rectangular plate-like member that seals the opening 12u of the exterior body 12. The sealing plate 14 faces the bottom 12d of the exterior body 12. The sealing plate 14 is substantially rectangular. The battery case 1 is integrated by joining (e.g., welding) the sealing plate 14 to the periphery of the opening 12u of the exterior body 12. Thereby, the battery case 1 is hermetically sealed. As shown in FIG. 2, the sealing plate 14 is provided with a liquid injection hole 15, a gas discharge valve 17, and terminal holes 18 and 19. The liquid injection hole 15 is a through hole for injecting the electrolytic solution into the battery case 1 after assembling the sealing plate 14 to the exterior body 12. The liquid injection hole 15 is sealed by a sealing member 16 after the injection of the electrolytic solution. The gas discharge valve 17 is a thin-walled portion configured to break when the pressure in the battery case 1 reaches a predetermined value or more and discharge the gas in the battery case 1 to the outside.

[0016] Although illustration is omitted, the electrolytic solution can be housed in the battery case 1 together with the electrode body 20 as described above. As the electrolytic solution, those used in conventionally known batteries can be used without particular limitation. As an example, a non-aqueous electrolytic solution in which a supporting salt (electrolyte salt) is dissolved in a non-aqueous solvent (organic solvent) is preferably used. As an example of the non-aqueous solvent, carbonate solvents such as ethylene carbonate, dimethyl carbonate, and ethyl methyl carbonate can be mentioned. As an example of the supporting salt, fluorine-containing lithium salts such as LiPF6 can be mentioned. The electrolytic solution may contain additives as necessary.

[0017] The positive electrode terminal 6 is attached to one end of the sealing plate 14 in the long side direction Y (the left end in FIGS. 1 and 2). The negative electrode terminal 8 is attached to the other end of the sealing plate 14 in the long side direction Y (the right end in FIGS. 1 and 2). The positive electrode terminal 6 and the negative electrode terminal 8 are inserted through the terminal holes 18 and 19 and exposed on the outer surface of the sealing plate 14. The positive electrode terminal 6 is electrically connected to the positive electrode 3 of the electrode body 20 through the positive electrode current collector 35 inside the exterior body 12. The negative electrode terminal 8 is electrically connected to the negative electrode 4 of the electrode body 20 through the negative electrode current collector 45 inside the exterior body 12. A current interruption mechanism (CID) may be installed between the positive electrode terminal 6 and the positive electrode current collector 35 or between the negative electrode terminal 8 and the negative electrode current collector 45. The positive electrode terminal 6 and the negative electrode terminal 8 are examples of terminals in the technology disclosed herein.

[0018] The positive electrode terminal 6 is electrically connected to the plate-shaped positive electrode external conductive member 70 outside the battery case 1. The negative electrode terminal 8 is electrically connected to the plate-shaped negative electrode external conductive member 71 outside the battery case 1. The positive electrode external conductive member 70 and the negative electrode external conductive member 71 are connected to other batteries or external devices through an external connection member such as a bus bar. The positive electrode external conductive member 70 and the negative electrode external conductive member 71 are preferably made of a metal having excellent conductivity, and are, for example, made of aluminum, an aluminum alloy, copper, a copper alloy, or the like. The positive electrode external conductive member 70 and the negative electrode external conductive member 71 are insulated from the sealing plate 14 by the external resin member 74. However, the positive electrode external conductive member 70 and the negative electrode external conductive member 71 are not essential and may be omitted in other embodiments.

[0019] The positive electrode terminal 6 is preferably made of metal, and more preferably made of aluminum or an aluminum alloy, for example. The negative electrode terminal 8 is preferably made of metal, and more preferably made of copper or a copper alloy, for example. The negative electrode terminal 8 may be configured by joining and integrating two conductive members. For example, the portion connected to the negative electrode current collector 45 may be made of copper or a copper alloy, and the portion exposed on the outer surface of the sealing plate 14 may be made of aluminum or an aluminum alloy.

[0020] As shown in FIG. 3, here, a plurality (here, three) of electrode bodies 20 are accommodated in the battery case 1 such that the thickness direction of each electrode body 20 (also referred to as the “stacking direction of the electrode bodies 20”. Here, it is the short side direction X.) is the same direction. However, the number of electrode bodies 20 disposed inside one exterior body 12 is not particularly limited, and may be two or more (plural) or one. As shown in FIGS. 2 and 3, the electrode body 20 is disposed inside the exterior body 12 in a state covered with an electrode body folder 9 made of a resin sheet. Thereby, it is possible to prevent the electrode body 20 from directly contacting the exterior body 12.

[0021] FIG. 4 is a schematic diagram showing the configuration of the electrode body 20. As shown in FIG. 4, the electrode body 20 has a positive electrode 3 and a negative electrode 4. As shown in FIG. 4, here, the electrode body 20 is a flat wound electrode body in which a strip-shaped positive electrode 3 and a strip-shaped negative electrode 4 are laminated in an insulated state via a strip-shaped separator 7 and wound around a winding axis WL. However, the electrode body 20 may be a laminated electrode body in which a plurality of rectangular (typically rectangular) positive electrodes and a plurality of rectangular (typically rectangular) negative electrodes are stacked in an insulated state. As shown in FIG. 3, the electrode body 20 has a pair of curved surface portions 21 facing the bottom portion 12d of the exterior body 12 and the sealing plate 14, and a flat portion 22 that connects the pair of curved surface portions 21 and faces the long side wall 12a of the exterior body 12.

[0022] As shown in FIG. 4, the positive electrode 3 has a positive electrode current collector foil 30, a positive electrode active material layer 31 fixed on at least one surface of the positive electrode current collector foil 30, and a positive electrode protective layer 32. However, the positive electrode protective layer 32 is not essential and may be omitted in other embodiments. The positive electrode current collector foil 30 is made of a conductive metal such as aluminum, an aluminum alloy, nickel, or stainless steel, and preferably made of aluminum or an aluminum alloy. The positive electrode active material layer 31 is a layer containing a positive electrode active material (for example, a lithium transition metal composite oxide such as lithium nickel cobalt manganese composite oxide) that can reversibly occlude and release charge carriers. The positive electrode protective layer 32 is a layer containing an inorganic filler such as alumina, for example.

[0023] As shown in FIG. 4, the negative electrode 4 includes a negative electrode current collector foil 40 and a negative electrode active material layer 41 fixed on the negative electrode current collector foil 40. The negative electrode current collector foil 40 is made of a conductive metal such as copper, a copper alloy, nickel, or stainless steel, and preferably made of copper or a copper alloy. The negative electrode active material layer 41 is a layer containing a negative electrode active material (for example, a carbon material such as graphite) that can reversibly occlude and release charge carriers.

[0024] The separator 7 is a member that insulates the positive electrode active material layer 31 of the positive electrode 3 and the negative electrode active material layer 41 of the negative electrode 4. As the separator 7, for example, a porous resin sheet made of a polyolefin resin such as polyethylene (PE) or polypropylene (PP) is suitable. Note that a heat resistance layer (HRL) containing an inorganic filler may be provided on the surface of the separator 7.

[0025] A plurality of positive electrode tabs 50 are provided at one end (the left end in FIG. 4) in the long side direction Y of the positive electrode current collector foil 30. The plurality of positive electrode tabs 50 each protrude toward one side in the long side direction Y (the left side in FIG. 4). The plurality of positive electrode tabs 50 protrude in the long side direction Y more than the separator 7. The shape and size of the positive electrode tab 50 can be appropriately adjusted depending on, for example, the state of connection to the positive electrode current collector 35 and its formation position. The positive electrode tab 50 is preferably made of a metal foil, and more preferably made of an aluminum foil or an aluminum alloy foil. Here, the positive electrode tab 50 is a portion (so-called current collector foil exposed portion) where the positive electrode active material layer 31 and the positive electrode protective layer 32 of the positive electrode current collector foil 30 are not formed. However, the positive electrode tab 50 may be a member separate from the positive electrode current collector foil 30.

[0026] At one end of the negative electrode current collector foil 40 in the long side direction Y (the right end in FIG. 4), a plurality of negative electrode tabs 60 are provided. The plurality of negative electrode tabs 60 project toward one side in the long side direction Y (the right side in FIG. 4). The plurality of negative electrode tabs 60 project in the long side direction Y more than the separator 7. The shape and size of the negative electrode tab 60 can be appropriately adjusted according to, for example, the formed position and the like in consideration of the state of being connected to the negative electrode current collector 45. The negative electrode tab 60 is preferably made of a metal foil, and more preferably made of a copper foil or a copper alloy foil. Here, the negative electrode tab 60 is a portion where the negative electrode active material layer 41 of the negative electrode current collector foil 40 is not formed (a so-called current collector foil exposed portion). However, the negative electrode tab 60 may be a member different from the negative electrode current collector foil 40.

[0027] As shown in FIG. 2, a plurality of positive electrode tabs 50 are laminated at one end in the long side direction Y (the left end in FIG. 2) to form a positive electrode tab group 54. On the other hand, a plurality of negative electrode tabs 60 are laminated at one end in the long side direction Y (the right end in FIG. 2) to form a negative electrode tab group 64. Here, the battery 100 has a so-called horizontal tab structure in which the positive electrode tab group 54 and the negative electrode tab group 64 are located on the left and right sides of the electrode body 20. The positive electrode tab group 54 is curved in a state of being joined to the positive electrode current collector 35. Similarly, the negative electrode tab group 64 is curved in a state of being joined to the negative electrode current collector 45.

[0028] The positive electrode current collector 35 constitutes a conduction path that electrically connects the positive electrode tab group 54 of the electrode body 20 and the positive electrode terminal 6. The positive electrode current collector 35 is an example of the "current collector" in the technology disclosed herein. As shown in FIG. 2, the positive electrode current collector 35 includes a first positive electrode current collector 36 and a second positive electrode current collector 38. Here, the first positive electrode current collector 36 has a base portion 36a and a protruding portion 36b. The first positive electrode current collector 36 may be formed by bending a single member, for example, by press working or the like, or may be formed by integrating a plurality of members by welding or the like. The base portion 36a is a portion disposed between the sealing plate 14 and the electrode body 20. The base portion 36a extends along the long side direction Y. The base portion 36a extends horizontally along the inner surface of the sealing plate 14. Here, the base portion 36a is electrically connected to the lower end portion 6c of the positive electrode terminal 6 by caulking. The protruding portion 36b is a portion disposed between the short side wall 12b of the exterior body 12 and the electrode body 20. The protruding portion 36b extends from one end (the left end in FIG. 2) of the base portion 36a in the long side direction Y toward the short side wall 12b of the exterior body 12. The protruding portion 36b extends along the vertical direction Z. The end portion of the protruding portion 36b is electrically connected to the second positive electrode current collector 38. As shown in FIG. 2, the second positive electrode current collector 38 is a plate-shaped conductive member that extends along the vertical direction Z here. The end portion of the second positive electrode current collector 38 is electrically connected to the positive electrode tab group 54. The positive electrode terminal 6 and the positive electrode current collector 35 (the first positive electrode current collector 36 and the second positive electrode current collector 38) are preferably composed of a metal having excellent conductivity. Preferably, it is composed of, for example, aluminum or an aluminum alloy.

[0029] The negative electrode current collector 45 constitutes a conduction path that electrically connects the negative electrode tab group 64 of the electrode body 20 and the negative electrode terminal 8. The negative electrode current collector 45 is an example of the "current collector" in the technology disclosed herein. As shown in FIG. 2, the negative electrode current collector 45 includes a negative electrode first current collector 46 and a negative electrode second current collector 48. Here, the negative electrode first current collector 46 has a base portion 46a and a protruding portion 46b. The negative electrode first current collector 46 may be formed by bending a single member, for example, by pressing or the like, or may be formed by integrating a plurality of members by welding or the like. The base portion 46a is a portion disposed between the sealing plate 14 and the electrode body 20. The base portion 46a extends along the long side direction Y. The base portion 46a extends horizontally along the inner surface of the sealing plate 14. Here, the base portion 46a is electrically connected to the lower end portion 8c of the negative electrode terminal 8 by caulking. The protruding portion 46b is a portion disposed between the short side wall 12b of the exterior body 12 and the electrode body 20. The protruding portion 46b extends from one end (the right end in FIG. 2) of the base portion 46a in the long side direction Y toward the short side wall 12b of the exterior body 12. The protruding portion 36b extends along the vertical direction Z. The end portion of the protruding portion 36b is electrically connected to the negative electrode second current collector 48. As shown in FIG. 2, the negative electrode second current collector 48 is a plate-shaped conductive member that extends along the vertical direction Z here. The end portion of the negative electrode second current collector 48 is electrically connected to the negative electrode tab group 64. The negative electrode terminal 8 and the negative electrode current collector 45 (the negative electrode first current collector 46 and the negative electrode second current collector 48) are preferably made of a metal having excellent conductivity, for example, copper or a copper alloy.

[0030] As shown in FIG. 2, here, the battery 100 has a substantially symmetric structure with respect to the center line CL of the battery 100 in the long side direction Y. Note that "substantially symmetric" in the technology disclosed here refers to being symmetric when viewed roughly. For example, as shown in FIG. 2, here, the liquid injection hole 15 is arranged on the positive electrode terminal 6 side (left side) with respect to the center line CL of the battery 100. Also, for example, the positive electrode terminal 6, the positive electrode current collector 35, and the negative electrode terminal 8, the negative electrode current collector 45, etc. may have different thicknesses, shapes, etc. depending on the material. For example, as shown in FIG. 2, here, the positive electrode terminal 6 and the negative electrode terminal 8 do not have the same shape. Therefore, even if the details (for example, terminal shape, etc.) are different, if it is symmetric when viewed roughly, it is included in "substantially symmetric".

[0031] FIG. 5 is a partially enlarged view schematically showing the vicinity of the positive electrode terminal 6 in FIG. 2. Note that hereinafter, the structure on the positive electrode terminal 6 side will be described in detail as an example, but the structure on the negative electrode terminal 8 side may be the same. In that case, in the following description, the parts of "positive electrode" can be appropriately read as "negative electrode".

[0032] <Resin insulating member 80> As shown in FIG. 5, the resin insulating member 80 has a first region 81, a second region 82, a third region 83, a fourth region 84, a fifth region 85, and a gasket portion 86. Here, the first region 81, the second region 82, the third region 83, the fourth region 84, the fifth region 85, and the gasket portion 86 are integrally formed. As shown in FIG. 3, on the upper surface (sealing plate 14 side) of the base portion 36a of the first positive current collector 36, the resin insulating member 80 forms the third region 83 along the short side direction X, and from both ends of the third region 83, it wraps around the side surface of the base portion 36a of the first positive current collector 36 in the vertical direction Z. Then, on the lower surface (electrode body 20 side) of the base portion 36a of the first positive current collector 36, the resin insulating member 80 forms the second region 82 along the short side direction X. That is, the resin insulating member 80 is integrated with the first positive current collector 36 by integral molding (insert molding). Thereby, compared with the case where the above configuration is made of separate members, the number of members to be used can be reduced, and cost reduction can be achieved. However, as shown in FIG. 5, here, the resin insulating member 80 is not integrally molded with the second positive current collector 38. The resin insulating member 80 is made of, for example, a fluororesin such as perfluoroalkoxyalkane (PFA) or polytetrafluoroethylene (PTFE), or a synthetic resin material such as polyphenylene sulfide (PPS). Inorganic fillers or the like may be added to such a synthetic resin material.

[0033] The first region 81 is a region disposed between the protruding portion 36b of the first positive current collector 36 and the electrode body 20 in the vertical direction Z from the sealing plate 14 toward the bottom 12d of the exterior body 12. The first region 81 extends in the vertical direction Z along the protruding portion 36b of the first positive current collector 36. By arranging the first region 81 in such a configuration, it serves to reduce the gap S1 between the electrode body 20 and the protruding portion 36b of the first positive current collector 36 in the long side direction Y. Thereby, the movement of the electrode body 20 in the horizontal direction (long side direction Y) is restricted. Therefore, damage to the electrode body 20 can be prevented. The vertical direction Z is an example of the "vertical direction from the sealing plate toward the bottom of the battery case" in the technology disclosed herein. Also, the first region 81 is an example of the "region disposed at a position facing the electrode body between the current collector and the side wall among the resin insulating members" in the technology disclosed herein.

[0034] To preferably restrict the movement of the electrode body 20 in the horizontal direction, in the long side direction Y, the shortest distance L1 between the electrode body 20 and the first region 81 is preferably, for example, 2 mm or less, and more preferably 1 mm or less. When the shortest distance L1 is 0 mm (i.e., the first region 81 and the electrode body 20 are in contact), the movement of the electrode body 20 in the horizontal direction is more preferably restricted. However, it is not necessarily required that the shortest distance L1 be 0 mm. When the shortest distance L1 is greater than 0 mm (i.e., the first region 81 and the electrode body 20 are separated), the manufacturing of the battery 100 (for example, the current collector joining process described later) can be easily performed.

[0035] In some preferred embodiments, the resin insulating member 80 includes a second region 82. The second region 82 is a region disposed between the lower part of the base portion 36a of the first positive current collector 36 and the electrode body 20 in the long side direction Y. The second region 82 is formed along the base portion 36a of the first positive current collector 36 in the long side direction Y. As shown in FIG. 3, the second region 82 is disposed along the base portion 36a of the first positive current collector 36 so as to face the curved surface portion 21 of the electrode body 20. By disposing the second region 82 in such a configuration, it serves to reduce the gap S2 between the curved surface portion 21 of the electrode body 20 and the base portion 36a of the first positive current collector 36 in the vertical direction Z. Thereby, the movement of the electrode body 20 in the vertical direction Z is restricted. Therefore, damage to the electrode body 20 can be more preferably prevented. The long side direction Y is an example of the "lateral direction orthogonal to the vertical direction" in the technology disclosed herein. Further, the second region 82 is an example of the "region in the resin insulating member that is disposed along the current collector and faces the electrode body between the current collector and the electrode body" in the technology disclosed herein.

[0036] To preferably restrict the movement of the electrode body 20 in the vertical direction, in the vertical direction Z, the shortest distance L2 between the electrode body 20 and the second region 82 is preferably, for example, 2 mm or less, and more preferably 1 mm or less. When the shortest distance L2 is 0 mm (i.e., the second region 82 and the curved surface portion 21 of the electrode body 20 are in contact), the movement of the electrode body 20 in the vertical direction is more preferably restricted. However, it is not necessarily required that the shortest distance L2 is 0 mm. When the shortest distance L2 is greater than 0 mm (i.e., the second region 82 and the curved surface portion 21 of the electrode body 20 are separated), the manufacture of the battery 100 (for example, the current collector joining step described later) can be easily performed.

[0037] In some preferred embodiments, the resin insulating member 80 includes a third region 83. The third region 83 is a region disposed between the base portion 36a of the first positive current collector 36 and the sealing plate 14 in the long side direction Y. As shown in FIG. 5, the third region 83 extends horizontally along the upper portion of the base portion 36a of the first positive current collector 36. The third region 83 serves to insulate the sealing plate 14 and the first positive current collector 36. By including the third region 83, the vibration resistance of the first positive current collector 36 and the resin insulating member 80 in the vertical direction Z is improved. That is, the reliability of the vibration resistance of the electrode body 20 can be improved. Further, as shown in FIG. 3, the second region 82 and the third region 83 serve as bosses with respect to the base portion 36a of the first positive current collector 36. Therefore, the bonding reliability between the first positive current collector 36 and the resin insulating member 80 can be further improved. The third region 83 is an example of "the region disposed between the current collector and the sealing plate among the resin insulating members" in the technology disclosed herein.

[0038] In some preferred embodiments, the resin insulating member 80 includes a fourth region 84. The fourth region 84 is a region disposed between the protruding portion 36b of the first positive current collector 36 and the short side wall 12b of the exterior body 12 in the vertical direction Z from the sealing plate 14 toward the bottom 12d of the exterior body 12. As shown in FIG. 5, the fourth region 84 extends in the vertical direction Z along the protruding portion 36b of the first positive current collector 36. The fourth region 84 serves to insulate the exterior body 12 (for example, the short side wall 12b) and the first positive current collector 36. By including the fourth region 84, the vibration resistance of the first positive current collector 36 and the resin insulating member 80 in the long side direction Y is improved. That is, the reliability of the vibration resistance of the electrode body 20 can be improved.

[0039] The first region 81 and the fourth region 84 are integrated such that at least a part of the regions allows the resin insulating member 80 to wrap around the peripheral edge (on the long side wall 12a side) of the protruding portion 36b of the first positive current collector 36. That is, the first region 81 and the fourth region 84 serve as boss portions with respect to the protruding portion 36b of the first positive current collector 36. Therefore, the bonding reliability between the first positive current collector 36 and the resin insulating member 80 can be further improved. As shown in FIG. 5, when the third region 83 and the fourth region 84 are integrated, the resin insulating member 80 is disposed so as to fill the gap connected to the short side wall 12b through the opening 12u from the sealing plate 14. Therefore, it becomes possible to preferably fix the resin insulating member 80 inside the battery case 1. And according to such a configuration, even when a strong impact is applied inside the battery case 1 such that the positions of the electrode body 20 and the positive current collector 35 are displaced, the resin insulating member 80 suppresses the electrode body 20 and the positive current collector 35 from protruding in the direction outside the battery case 1. Therefore, damage to the electrode body 20 can be reduced.

[0040] As shown in FIGS. 2 and 5, the gasket portions 86 are respectively disposed between the positive electrode terminal 6 and the sealing plate 14, and between the negative electrode terminal 8 and the sealing plate 14. The gasket portions 86 have a function of insulating the positive electrode terminal 6 and the sealing plate 14, and the negative electrode terminal 8 and the sealing plate 14, and closing the terminal holes 18 and 19. As shown in FIG. 5, here, the gasket portions 86 are integrally formed with the resin insulating member 80. Thereby, the number of members of the battery 100 can be further reduced, and the assembling man-hour of the battery 100 can be reduced. However, it is not limited thereto, and the gasket portions 86 may be separate members from the resin insulating member 80 (that is, independent as gaskets). The gasket portions 86 are an example of "the region disposed between the terminal and the sealing plate" in the technology disclosed herein.

[0041] In some preferred embodiments, the resin insulating member 80 includes a fifth region 85. The fifth region 85 is a region that protrudes toward the electrode body 20 from a region where the base portion 36a of the positive electrode first current collector 36 is not formed among the ends of the third region 83 that extends from the short side wall 12b to the center line CL (the side where the fourth region 84 is not formed) in the long side direction Y. According to such a configuration, inside the battery case 1, the movement of the electrode body 20 in the vertical direction Z can be more preferably restricted. Regarding the detailed structure of the fifth region 85, it may be the same as the second region 82 except that it is not integrated with the positive electrode first current collector 36.

[0042] In addition, it is preferable to perform a roughening treatment on at least a part of the surfaces of the sealing plate 14, the positive electrode terminal 6, the positive electrode first current collector 36, the negative electrode terminal 8, and the negative electrode first current collector 46 that are in contact with the resin insulating member 80. Here, the "roughening treatment" is a treatment for increasing the surface area by forming irregularities (forming a rough surface portion) on the surface. Thereby, the anchor effect can be enhanced, and the bonding property and adhesion with the resin insulating member 80 can be further improved. Such a roughening treatment can be performed, for example, by laser irradiation or sandblasting. Here, the sealing plate 14, the positive electrode terminal 6, the positive electrode first current collector 36, the negative electrode terminal 8, and the negative electrode first current collector 46 are joined to the resin insulating member 80 by the anchor effect.

[0043] As described above, in the battery 100 including the resin insulating member 80 having the above configuration, by restricting the movement of the electrode body 20, damage to the electrode body 20 can be prevented. And the number of parts of the battery 100 is reduced, and the assembly man-hours of the battery 100 can be reduced.

[0044] <Manufacturing method of battery 100> The manufacturing method of the battery 100 is characterized by molding the resin insulating member 80 as described above in a resin insulating member molding step to be described later. Other manufacturing processes may be the same as those in the prior art. The battery 100 includes the battery case 1 (the outer package 12 and the sealing plate 14) as described above, the electrode body 20 (one or more, here three), the positive electrode terminal 6, the negative electrode terminal 8, the positive electrode current collector 35 (the first positive electrode current collector 36 and the second positive electrode current collector 38), the negative electrode current collector 45 (the first negative electrode current collector 46 and the second negative electrode current collector 48), and the electrolytic solution. For example, it can be manufactured by a manufacturing method typically including a sealing plate mounting step, a resin insulating member molding step, a tab group joining step, a current collector joining step, and a sealing step in this order. Further, the manufacturing method disclosed herein may further include other steps at any stage.

[0045] (Sealing Plate Mounting Step) In the sealing plate mounting step, the positive electrode terminal 6, the first positive electrode current collector 36, the negative electrode terminal 8, and the first negative electrode current collector 46 are attached to the sealing plate 14. The positive electrode terminal 6 and the first positive electrode current collector 36 are fixed to the sealing plate 14 by, for example, caulking (riveting). Specifically, the positive electrode terminal 6 before caulking is inserted from above (U side) of the sealing plate 14 in the order of the terminal hole 18 and the first positive electrode current collector 36, and projected below the sealing plate 14. Then, the portion of the positive electrode terminal 6 projecting below the sealing plate 14 is caulked so that a compressive force is applied in the vertical direction Z. As a result, a lower end portion 6c is formed at the tip end portion (the lower end portion in FIG. 2) of the positive electrode terminal 6. Thereby, the positive electrode terminal 6 and the first positive electrode current collector 36 are integrally fixed to the sealing plate 14. Note that the lower end portion 6c may be welded and joined to the first positive electrode current collector 36. Thereby, the conduction reliability can be further improved.

[0046] In the process of attaching the sealing plate, the fixing of the negative electrode terminal 8 and the first negative electrode current collector 46 can be performed in the same manner as on the positive electrode side described above. That is, the negative electrode terminal 8 before caulking is inserted in order from above (U side) of the sealing plate 14 into the terminal hole 19 of the sealing plate 14 and the through hole of the first negative electrode current collector 46, and protruded below the sealing plate 14. Then, the portion of the negative electrode terminal 8 protruding below the sealing plate 14 is caulked so that a compressive force is applied in the vertical direction Z. Thereby, a lower end portion 8c is formed at the tip portion (the lower end portion in FIG. 2) of the negative electrode terminal 8.

[0047] (Resin Insulating Member Molding Process) In the resin insulating member molding process, a resin insulating member 80 is molded. The resin insulating member 80 can be produced, for example, by insert molding the sealing plate 14, the positive electrode terminal 6, the first positive electrode current collector 36, the negative electrode terminal 8, and the first negative electrode current collector 46. Thereby, it becomes possible to reduce the number of parts. The insert molding can be performed according to a conventionally known method as described in, for example, JP-A-2021-086813, JP-A-2021-086814, Patent No. 3986368, Patent No. 6648671, etc. For example, it can be produced by a method including a part setting process, a positioning process, an upper mold setting process, an injection molding process, an upper mold release process, and a part taking-out process using a molding die having a lower mold and an upper mold.

[0048] In the component set process, a sealing plate 14 to which a positive electrode terminal 6, a first positive electrode current collector 36, a negative electrode terminal 8, and a first negative electrode current collector 46 are attached is mounted on the lower mold. In the positioning process, the positive electrode terminal 6, the first positive electrode current collector 36, the negative electrode terminal 8, and the first negative electrode current collector 46 are positioned and fixed. In the upper mold set process, the upper mold is mounted so as to sandwich the first positive electrode current collector 36, the first negative electrode current collector 46, the positive electrode terminal 6, and the negative electrode terminal 8 in the vertical direction together with the lower mold. In the injection molding process, first, the molding die is heated. Next, molten resin is injected into the molding die. On the side of the positive electrode terminal 6, the molten resin flows from the upper mold through the terminal hole 18 and wraps around the periphery of the first positive electrode current collector 36 and then flows into the lower mold. On the other hand, on the side of the negative electrode terminal 8, the molten resin flows from the upper mold through the terminal hole 19 and wraps around the periphery of the first negative electrode current collector 46 and then flows into the lower mold. Thereafter, the molding die and the molded product are cooled. Thereby, a resin insulating member 80 is molded. In the upper mold release process, the upper mold is separated from the lower mold. In the component removal process, the molded product is removed from the lower mold.

[0049] (Tab group joining process) In the tab group joining process, the positive electrode tab group 54 and the second positive electrode current collector 38, and the negative electrode tab group 64 and the second negative electrode current collector 48 are electrically joined. Here, ultrasonic joining using an ultrasonic horn and an anvil (receiving jig) will be described as an example, but the joining method in the tab group joining process is not limited to this, and for example, welding such as laser welding may be used. Although illustration is omitted, when performing the tab group joining process by ultrasonic joining, the positive electrode tab group 54, the second positive electrode current collector 38, the ultrasonic horn, and the anvil are sandwiched. Then, by vibrating the ultrasonic horn while pressing the ultrasonic horn in the direction of the anvil, the positive electrode tab group 54 and the second positive electrode current collector 38 are joined. Note that the joining method of the negative electrode tab group 64 and the second negative electrode current collector 48 may be the same as the joining method of the positive electrode tab group 54 and the second positive electrode current collector 38 described above.

[0050] (Current collector joining process) In the current collector joining process, the first positive current collector 36 is joined to the second positive current collector 38, and the first negative current collector 46 is joined to the second negative current collector 48. Specifically, with the positive tab group 54 in a curved state, the first positive current collector 36 fixed to the sealing plate 14 and the second positive current collector 38 connected to the electrode body 20 via the positive tab group 54 are joined respectively. Also, with the plurality of negative tab groups 64 in a curved state, the first negative current collector 46 fixed to the sealing plate 14 and the second negative current collector 48 connected to the electrode body 20 via the negative tab group 64 are joined respectively. As the joining method, for example, welding such as ultrasonic welding, resistance welding, laser welding, etc. can be used.

[0051] (Sealing process) In the sealing process, the electrode body 20 integrated with the sealing plate 14 is wrapped by the electrode body folder 9 and inserted (accommodated) into the exterior body 12. Then, the sealing plate 14 is pushed into the direction of the bottom 12d of the exterior body 12. And the exterior body 12 (opening 12u) and the sealing plate 14 are sealed. Sealing can be performed by welding such as laser welding, for example. After that, the electrolyte is injected through the liquid injection hole 15, and the liquid injection hole 15 is sealed with the sealing member 16, thereby sealing the battery 100. In this way, the battery 100 can be manufactured.

[0052] The battery 100 can be used for various applications, but it is preferably used as a power source (driving power source) for motors mounted on vehicles such as passenger cars and trucks, where external forces such as vibration and impact may be applied during use. The type of vehicle is not particularly limited, and examples include plug-in hybrid electric vehicles (PHEV), hybrid electric vehicles (HEV), battery electric vehicles (BEV), etc. Also, the battery 100 can be used as a battery pack.

[0053] Although some embodiments according to the technology disclosed herein have been described above, the above embodiments are merely examples. The technology disclosed herein can be implemented in various other forms. The technology disclosed herein can be implemented based on the content disclosed in this specification and common general knowledge in the art. The technology described in the claims includes various modifications and changes to the above-exemplified embodiments. For example, it is possible to replace a part of the above-described embodiments with other modified forms, and it is also possible to add other modified forms to the above-described embodiments. Also, if the technical features are not described as essential, they can be appropriately deleted.

[0054] For example, in the above-described embodiment, resin insulating members 80 were provided on the positive electrode 3 (positive electrode terminal 6) side and the negative electrode 4 (negative electrode terminal 8) side, respectively. However, it is not limited thereto. The resin insulating member 80 may be provided only on either the positive electrode 3 side or the negative electrode 4 side. Even in such a configuration, the vibration suppressing effect of the electrode body 20 can be exhibited. However, when resin insulating members 80 are provided on the positive electrode 3 side and the negative electrode 4 side, respectively, the vibration resistance of the electrode body 20 is more preferably improved.

[0055] Also, in the above-described embodiment, the external resin member 74 and the resin insulating member 80 had independent configurations. However, it is not limited thereto. The external resin member 74 may be integrally formed with the resin insulating member 80 (in other words, the external resin member 74 is configured as a part of the resin insulating member 80). According to such a configuration, it is more preferably possible to reduce the number of parts of the battery 100.

[0056] Also, in the above-described embodiment, the battery 100 was substantially symmetric with respect to the center line CL. However, it is not limited thereto. For example, the battery 100 may be asymmetric with respect to the center line CL. Even when the battery 100 is asymmetric with respect to the center line CL, by providing the above-described resin insulating member 80, damage to the electrode body 20 can be preferably prevented.

[0057] As described above, specific embodiments of the technology disclosed herein include those described in the following items. Item 1: A battery comprising: an electrode body having a positive electrode and a negative electrode; an exterior body having a bottom portion, an opening facing the bottom portion, and a side wall extending from an end portion of the bottom portion toward the opening and accommodating the electrode body; a sealing plate having a terminal hole and sealing the opening; a current collector disposed within the exterior body and electrically connected to the positive electrode or the negative electrode; a terminal inserted through the terminal hole and attached to the sealing plate and electrically connected to the current collector within the exterior body; and a resin insulating member that insulates at least a part of the current collector and at least a part of the sealing plate, wherein the resin insulating member is integrally formed with at least a part of the current collector, and at least a part of the resin insulating member is disposed at a position facing the electrode body between the current collector and the side wall in a vertical direction from the sealing plate toward the bottom portion of the exterior body. Item 2: The battery according to Item 1, wherein at least a part of the resin insulating member is disposed so as to face the electrode body along the current collector between the current collector and the electrode body in a horizontal direction orthogonal to the vertical direction. Item 3: The battery according to Item 1 or 2, wherein at least a part of the resin insulating member is disposed between the current collector and the sealing plate. Item 4: The battery according to any one of Items 1 to 3, wherein at least a part of the resin insulating member is disposed between the terminal and the sealing plate. Item 5: The battery according to any one of Items 1 to 4, wherein at least a part of the resin insulating member is joined to the sealing plate, the terminal, and the current collector by an anchor effect.

Description of Reference Numerals

[0058] 1 Battery case 3 Positive electrode 4 Negative electrode 6 Positive electrode terminal 7 Separator 8 Negative electrode terminal 9 Electrode body folder 12 Outer package 12d Bottom 12a Long side wall 12b Short side wall 12u Opening 14 Sealing plate 20 Electrode body 30 Positive current collector foil 31 Positive active material layer 32 Positive protective layer 35 Positive current collector 36 First positive current collector 36a Base part of the first positive current collector 36b Protruding part of the first positive current collector 38 Second positive current collector 40 Negative current collector foil 41 Negative active material layer 45 Negative current collector 46 First negative current collector 46a Base part of the first negative current collector 46b Protruding part of the first negative current collector 48 Second negative current collector 50 Positive tab 54 Positive tab group 60 Negative tab 64 Negative tab group 74 External resin member 80 Resin insulating member 81 First region 82 Second region 83 Third region 84 Fourth region 85 Fifth region 86 Gasket part 100 Battery

Claims

1. An electrode body having a positive electrode and a negative electrode; An exterior body having a bottom, an opening facing the bottom, a long side wall extending from the long side of the bottom toward the opening, and a short side wall extending from the short side of the bottom toward the opening, for housing the electrode body; A sealing plate having a terminal hole for sealing the opening; A current collector disposed within the exterior body and electrically connected to the positive electrode or the negative electrode; A terminal electrically connected to the current collector within the exterior body, inserted through the terminal hole, and attached to the sealing plate; At least one of the positive electrode or the negative electrode includes a resin insulating member that insulates at least a part of the current collector and the sealing plate; Comprising: The current collector includes: A base portion disposed between the sealing plate and the electrode body; A protruding portion disposed between the short side wall of the exterior body and the electrode body, extending along the longitudinal direction from the sealing plate toward the bottom of the exterior body; Here, the resin insulating member includes: In the longitudinal direction, a first region disposed along the protruding portion of the current collector and between the protruding portion of the current collector and the electrode body; In the longitudinal direction, a fourth region disposed between the protruding portion of the current collector and the short side wall; The resin insulating member is integrally formed with at least a part of the current collector. A battery.

2. The battery according to claim 1, wherein the resin insulating member further has a second region disposed in a lateral direction orthogonal to the longitudinal direction, between the base portion of the current collector and the electrode body, along the base portion of the current collector, and facing the electrode body.

3. The battery according to claim 1, wherein the resin insulating member further has a third region disposed between the base portion of the current collector and the sealing plate.

4. The battery according to claim 1 or 2, wherein at least a part of the resin insulating member is disposed between the terminal and the sealing plate.

5. The battery according to claim 1 or 2, wherein at least a part of the resin insulating member is joined to the sealing plate, the terminal, and the current collector by an anchor effect.

6. The battery according to claim 3, wherein the resin insulating member further has a fifth region protruding toward the electrode body side from a region where the base portion of the current collector is not formed among the ends of the third region on the side where the fourth region is not formed in the lateral direction.

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