Battery and battery manufacturing method

Abstract

Provided is a battery (1) capable of activating a current shut-off valve (diaphragm (31)) by using proper actuation pressure. This battery (1) comprises: a charge / discharge body (10); a current collecting member (20) (positive electrode current collector (21)) conductive to the charge / discharge body (10); the current shut-off valve (diaphragm (31)) laminated and joined to the positive current collector (21); an external terminal (positive terminal (41)) conductive to the diaphragm (31); a support (33) that supports the diaphragm (31) along the lamination direction (Z-axis direction) of the positive electrode current collector (21) and the diaphragm (31); and a low-rigidity member (protruding part (33e)) aligned with the support base (33) along the Z-axis direction and configured to have lower rigidity than the support base (33).

Description

[Technical Field]

[0001] The present invention relates to a battery and a method for manufacturing the battery. [Background technology]

[0002] BACKGROUND ART Conventionally, a current interrupt device (CID) that physically opens and interrupts the current path of a battery when the internal pressure of the battery rises has been known (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-155200 Summary of the Invention [Problem to be solved by the invention]

[0004] The current cutoff valve is required to be actuated by an appropriate actuation pressure. [Means for solving the problem]

[0005] The battery of the present invention comprises a charging / discharging body, a current collecting member that is electrically connected to the charging / discharging body, a current cut-off valve that is stacked and joined to the current collecting member, an external terminal that is electrically connected to the current cut-off valve, a support member that supports the current cut-off valve along the stacking direction of the current collecting member and the current cut-off valve, and a low-rigidity member that is aligned with the support member along the stacking direction and has lower rigidity than the support member.

[0006] The method for manufacturing a battery of the present invention includes a first step of measuring the distance between the current collecting member and the current cutoff valve along the stacking direction, a second step of bringing the support member and the current collecting member relatively close to each other along the stacking direction and pressing the low-rigidity member and the current collecting member simultaneously with or after the first step, and a third step of joining the current collecting member and the current cutoff valve, which are in contact with each other, after the second step. [Effects of the Invention]

[0007] According to the battery of the present invention, the current cutoff valve can be operated by an appropriate operating pressure, and according to the battery manufacturing method of the present invention, productivity of batteries having a current cutoff valve can be improved. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view showing a battery 1 of a first embodiment. [Figure 2] FIG. 2 is a cross-sectional perspective view showing the periphery of a negative electrode terminal 42 of the battery 1 according to the first embodiment. [Figure 3] FIG. 2 is a cross-sectional view showing the periphery of a negative electrode terminal 42 of the battery 1 according to the first embodiment. [Figure 4] FIG. 2 is a cross-sectional perspective view showing the periphery of a positive electrode terminal 41 of the battery 1 according to the first embodiment. [Figure 5] FIG. 2 is a cross-sectional view showing the periphery of a positive electrode terminal 41 of the battery 1 according to the first embodiment. [Figure 6] 1 is an exploded perspective view showing a battery 1 according to a first embodiment. [Figure 7] 1 is a perspective view showing a charging / discharging unit 10 of a battery 1 according to a first embodiment. [Figure 8] 1 is a cross-sectional view showing a part of a charging / discharging body 10 of a battery 1 according to a first embodiment. [Figure 9] FIG. 4 is a cross-sectional view showing a part of a charging / discharging body 110 of a modified example of the battery 1 of the first embodiment. [Figure 10] FIG. 2 is an exploded perspective view showing the periphery of a negative electrode terminal 42 of the battery 1 according to the first embodiment. [Figure 11]FIG. 2 is an exploded perspective view showing the lid 52 and sealing plug 53 of the battery 1 of the first embodiment. [Figure 12] FIG. 2 is an exploded perspective view showing the periphery of a positive electrode terminal 41 of the battery 1 according to the first embodiment. [Figure 13] 3 is an exploded perspective view showing components around a current interrupter 30 of the battery 1 according to the first embodiment. FIG. [Figure 14] FIG. 14 is a perspective view showing the components of FIG. 13 from the rear side. [Figure 15] 3 is a side view showing a cross section of components such as a current interrupter 30 in a manufacturing method for the current interrupter 30 of the battery 1 according to the first embodiment. FIG. [Figure 16] Continuing from the state of Figure 15, this is a side view showing in cross section the state in which the positive electrode current collector 21 and the support base 33 are moved toward the conductive member 32, and then the distance between the positive electrode current collector 21 and the diaphragm 31 is measured along the Z-axis direction. [Figure 17] 16, the protrusion 33e of the support base 33 is plastically deformed while the positive current collector 21 is further moved toward the conductive member 32, thereby bringing the positive current collector 21 and the diaphragm 31 into contact with each other. [Figure 18] 18 is a side view showing in cross section a state in which the positive current collector plate 21 and the support base 33 are welded together and the positive current collector plate 21 and the diaphragm 31 are laser-welded together, following the state in FIG. 17. [Figure 19] 3A and 3B are side views showing cross sections of essential parts of a method for manufacturing the current interrupter 30 of the battery 1 according to the first embodiment. [Figure 20] 10 is a side view showing a cross section of a main part of a manufacturing method for a current interrupter 130 of a battery 2 according to a second embodiment. FIG. [Figure 21] 10 is a side view showing a cross section of a main part of a manufacturing method for a current interrupter 230 of a battery 3 according to a third embodiment. FIG. [Figure 22] 10 is a side view showing a cross section of a main part of a method for manufacturing a current interrupter 330 of a battery 4 according to a fourth embodiment. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] Each embodiment of the present invention will be described with reference to the drawings. To facilitate understanding of each embodiment, the size and proportions of components may be exaggerated in the drawings. In each embodiment, the same components are assigned the same reference numerals, and redundant description will be omitted. Each embodiment uses a left-handed XYZ Cartesian coordinate system with the X, Y, and Z axes as its coordinate axes. The arrows on each of the X, Y, and Z axes indicate the positive direction of the coordinate axis. The X axis is the coordinate axis in the longitudinal direction of the rectangular parallelepiped battery. The Y axis is the coordinate axis in the lateral direction of the battery. The Z axis is the coordinate axis in the height direction of the battery. However, the positional relationships expressed in the XYZ Cartesian coordinate system are merely relative positional relationships.

[0010] [First embodiment] (Configuration of Battery 1 of First Embodiment) The configuration of the battery 1 will be described with reference to FIGS.

[0011] 1 to 5, the battery 1 includes a charging / discharging body 10 that charges and discharges electricity, a current collecting member 20 connected to the charging / discharging body 10, a current interrupting body 30 connected to the current collecting member 20, an external terminal 40 connected to the current collecting member 20 or the current interrupting body 30, and an exterior body 50 that houses or attaches the components of the battery 1. The battery 1 also includes an insulator 60 that insulates the components of the battery 1 from the exterior body 50, and a sealing body 70 that seals the components of the battery 1 from the exterior body 50.

[0012] The charge / discharge unit 10 charges and discharges electricity. The charge / discharge unit 10 shown in Figures 2 to 8 includes a positive electrode 11, a negative electrode 12, a separator 13 (insulating member), and an electrolyte 14. As shown in Figure 7, the charge / discharge unit 10 is configured by winding components, in which the positive electrode 11, the separator 13, the negative electrode 12, and the separator 13 are stacked in this order, into a rectangular parallelepiped shape.

[0013] As shown in FIGS. 7 and 8, the positive electrode 11 includes a long positive electrode current collector foil 11S and a positive electrode active material layer 11T bonded to the positive electrode current collector foil 11S. The positive electrode current collector foil 11S includes a current collector portion 11a and a positive electrode tab 11b. The current collector portion 11a is wound. The positive electrode active material layer 11T is bonded to the current collector portion 11a. As shown in FIG. 8, the positive electrode active material layer 11T faces the entire area of ​​the current collector portion 11a along the short side direction (Z-axis direction), for example.

[0014] 7 and 8, the positive electrode tab 11b protrudes in the short direction of the current collecting part 11a from a side edge 11c along the longitudinal direction (winding direction) of the current collecting part 11a. The positive electrode tab 11b is formed integrally with the current collecting part 11a. For example, one positive electrode tab 11b is formed per current collecting part 11a.

[0015] The current collecting portion 11a of the positive electrode 11 is formed of, for example, aluminum or an aluminum alloy. The positive electrode active material layer 11T contains a positive electrode active material constituted by a lithium-containing composite oxide, a binder, a conductive additive, etc. The lithium-containing composite oxide contains, for example, a metal element such as nickel (Ni), cobalt (Co), or manganese (Mn), and lithium (Li).

[0016] As shown in FIGS. 7 and 8, the negative electrode 12 includes a long negative electrode current collector foil 12S and a negative electrode active material layer 12T bonded to the negative electrode current collector foil 12S. The negative electrode current collector foil 12S includes a current collector portion 12a and a negative electrode tab 12b. As shown in FIG. 8, the current collector portion 12a of the negative electrode 12 has a width along the short side direction (Z-axis direction) greater than that of the current collector portion 11a of the positive electrode 11. Both ends of the current collector portion 11a of the positive electrode 11 along the short side direction are located within the range along the short side direction of the current collector portion 12a of the negative electrode 12, with a separator 13 interposed between them. A negative electrode active material layer 12T is bonded to the current collector portion 12a. The negative electrode active material layer 12T faces, for example, the entire area of ​​the current collector portion 12a along the short side direction (Z-axis direction).

[0017] As shown in FIGS. 7 and 8, for example, the negative electrode tab 12b protrudes in the width direction of the current collecting part 12a from a side edge 12c along the longitudinal direction (winding direction) of the current collecting part 12a. When stacked with the positive electrode 11 via the separator 13, the negative electrode tab 12b protrudes in the same direction as the positive electrode tab 11b of the positive electrode 11. When stacked with the positive electrode 11 via the separator 13, the negative electrode tab 12b is separated from the positive electrode tab 11b of the positive electrode 11. The negative electrode tab 12b is formed integrally with the current collecting part 12a. For example, one negative electrode tab 12b is formed per current collecting part 12a.

[0018] The current collecting portion 12a of the negative electrode 12 is formed of, for example, copper or a copper alloy. The negative electrode active material layer 12T contains a negative electrode active material made of a carbon-based material, a binder, a conductive additive, etc. The carbon-based material is, for example, graphite.

[0019] As shown in FIGS. 7 and 8, the separator 13 (insulator) insulates the positive electrode 11 from the negative electrode 12 while allowing lithium ions to pass through. The separator 13 is formed in an elongated shape. The separator 13 has a width along its short side (Z-axis direction) greater than that of the current collector 11a of the positive electrode 11 and the current collector 12a of the negative electrode 12. Both ends of the current collector 11a of the positive electrode 11 along the short side are located within the short side of the separator 13, and both ends of the current collector 12a of the negative electrode 12 along the short side are located within the short side of the separator 13. The separator 13 is made of a porous material. Polyethylene (PE) or polypropylene (PP) is used for the separator 13. A heat-resistant insulating material may be used instead of the separator 13. The heat-resistant insulating material may be, for example, ceramic. This configuration is known as a separator-less configuration.

[0020] The electrolyte 14 corresponds to a so-called electrolytic solution. The electrolyte 14 is impregnated in the separator 13. The electrolyte 14 contains an organic solvent, a supporting salt, and an additive. The organic solvent may be, for example, a carbonate ester. The supporting salt may be, for example, a lithium salt.

[0021] A charge / discharge body 110, which is a modified example of the charge / discharge body 10, will be described with reference to FIG. 9. The charge / discharge body 110 differs in the configuration of the positive electrode 111 from the configuration of the positive electrode 11 of the first embodiment. In the configuration of the charge / discharge body 110, the same components as those of the charge / discharge body 10 are given the same reference numerals, and their description will be omitted. The positive electrode active material layer 111T of the charge / discharge body 110 faces the current collecting part 11a except for both ends along the short side direction (Z-axis direction). The heat-resistant insulating layer 111U of the charge / discharge body 110 is bonded to both ends along the short side direction of the current collecting part 11a and to the base end portion of the positive electrode tab 11b. The heat-resistant insulating layer 111U contains, for example, ceramics.

[0022] The current collecting member 20 is electrically connected to the charge / discharge body 10. The current collecting member 20 shown in Figures 2 to 5, 10, and 12 to 14 includes a positive current collecting plate 21 and a negative current collecting plate 22.

[0023] As shown in FIGS. 4 and 5, the positive current collector plate 21 electrically connects the positive electrode tab 11b of the charge / discharge unit 10 to the positive electrode terminal 41 via the current interrupter 30. As shown in FIG. 12, the positive current collector plate 21 includes a rectangular parallelepiped plate-shaped first base portion 21a, a rectangular parallelepiped plate-shaped second base portion 21b, and a connecting portion 21c that connects the first base portion 21a and the second base portion 21b in a stepped manner with different heights. As shown in FIGS. 13 and 14, a recess 21d is formed on the upper surface (the surface facing the positive Z-axis direction) of the second base portion 21b, by reducing the thickness of the second base portion 21b. The recess 21d is formed in an arc shape. A weak portion 21e, which is a ring-shaped recessed weak portion, is formed in the center of the recess 21d, as shown in FIGS. 13 and 14. The fragile portion 21e is configured to have relatively lower rigidity at a joint T with the diaphragm 31 than at the joint T. A through hole 21f is formed in the center of the recess 21d, as shown in Figures 13 and 14, for example. The through hole 21f is formed inside the fragile portion 21e in the recess 21d. The through hole 21f exposes the diaphragm 31 to the side of the charge / discharge body 10. A positioning hole 21g is formed in the second base portion 21b, into which a positioning pin 33c of a support base 33 of the current interrupter 30 is inserted. The positive electrode current collector 21 is made of, for example, aluminum or an aluminum alloy.

[0024] 2 and 3, the negative electrode current collector 22 electrically connects the negative electrode tab 12b of the charge / discharge body 10 to the negative electrode terminal 42. As shown in FIG. 10, the negative electrode current collector 22 includes a rectangular parallelepiped base 22a and an insertion hole 22b penetrating the base 22a. The insertion hole 22b of the negative electrode current collector 22 is inserted into the insertion hole 22b of the negative electrode current collector 22. The negative electrode current collector 22 is formed of, for example, copper or a copper alloy.

[0025] The current interrupter 30 is connected to the current collecting member 20 and provides electrical continuity between the current collecting member 20 and the positive electrode terminal 41. The current interrupter 30 shown in Figures 4, 5, and 12 to 14 includes a diaphragm 31, a conductive member 32, and a pair of support bases 33. The current interrupter 30 may be provided on the negative electrode terminal 42 side.

[0026] As shown in Figs. 12 to 14, the diaphragm 31 (current cutoff valve) is laminated and bonded to the positive current collector plate 21. As shown in Fig. 13, for example, the diaphragm 31 includes a curved cylindrical main body 31a, a disk-shaped first joint portion 31b provided at the tip end of the main body 31a, and a ring-shaped second joint portion 31c provided at the base end of the main body 31a. The first joint portion 31b is bonded to the recess 21d of the positive current collector plate 21. The second joint portion 31c is bonded to the conductive member 32. The diaphragm 31 is formed of, for example, aluminum or an aluminum alloy.

[0027] 12 to 14, the conductive member 32 is formed in a cylindrical shape. The positive electrode side first insulating plate 62 is joined to the upper surface of the conductive member 32. The second joint portion 31c of the diaphragm 31 is joined to the periphery of the lower surface of the conductive member 32. The conductive member 32 is formed of, for example, aluminum or an aluminum alloy.

[0028] As shown in FIGS. 12 to 14, the support base 33 (support member) supports the diaphragm 31 along the Z-axis direction, which corresponds to the stacking direction of the positive current collector plate 21 and the diaphragm 31. As shown in FIG. 14, for example, the support base 33 includes a rectangular parallelepiped main body 33a extending in the short-side direction of the battery 1 and a pair of legs 33b extending downward from both longitudinal sides of the main body 33a. One support base 33 is provided on each end of the diaphragm 31 along the longitudinal direction of the battery 1. The main body 33a is attached to the positive-side first insulating plate 62. Positioning holes 33d are formed in the main body 33a at both ends that overlap with the pair of legs 33b. Positioning pins 62d formed on the positive-side first insulating plate 62 are inserted into the positioning holes 33d. The legs 33b are attached to the second base 21b of the positive current collector plate 21. The leg portion 33b has a cylindrical positioning pin 33c extending downward. The positioning pin 33c is inserted into a positioning hole 21g of the positive current collector plate 21.

[0029] As shown in FIG. 14, for example, the support base 33 has a hemispherical protrusion 33e (low-rigidity member) extending downward from the leg 33b. The protrusion 33e is aligned with the positioning pin 33c on the leg 33b. The protrusion 33e is aligned with the support base 33 along the Z-axis direction and is configured to have lower rigidity than the support base 33. The protrusion 33e is formed integrally with the support base 33. The protrusion 33e protrudes in a hemispherical shape from the support base 33 toward the positive current collector plate 21. The protrusion 33e is configured to be plastically deformable. The support base 33 is formed, for example, from an insulating resin.

[0030] The external terminals 40 are connected to the current collecting members 20 or the current interrupters 30. The external terminals 40 shown in Figures 1 to 6, 10 and 12 include a positive terminal 41 and a negative terminal 42.

[0031] 5, the positive electrode terminal 41 is connected to the conductive member 32 of the current interrupter 30. That is, the positive electrode terminal 41 is electrically connected to the diaphragm 31. As shown in FIG. 12, the positive electrode terminal 41 includes a rectangular parallelepiped plate-shaped base 41a, a cylindrical insertion portion 41b protruding downward (in the negative Z-axis direction) from the base 41a, and a cylindrical joint portion 41c protruding downward (in the negative Z-axis direction) from the periphery of the base 41a.

[0032] 12, the base 41a is in contact with the base 64a of the positive electrode-side second insulating plate 64. The insertion portion 41b is inserted into the insertion hole 64b of the positive electrode-side second insulating plate 64, the positive electrode-side insertion hole 52a of the lid 52, the insertion hole 62b of the positive electrode-side first insulating plate 62, and the insertion hole 32b of the conductive member 32.

[0033] 12, the joint portion 41c protrudes downward (in the negative direction of the Z axis) from the insertion hole 32b of the conductive member 32 and is expanded radially outward to be joined to the conductive member 32. That is, the joint portion 41c is crimped to the periphery of the insertion hole 32b of the conductive member 32. Furthermore, the joint portion 41c is welded to the periphery of the insertion hole 32b of the conductive member 32. The positive electrode terminal 41 is formed of, for example, aluminum or an aluminum alloy.

[0034] The negative electrode terminal 42 is connected to the negative electrode current collector plate 22, as shown in Fig. 3, for example. As shown in Fig. 10, for example, the negative electrode terminal 42 includes a rectangular parallelepiped plate-shaped base portion 42a, a cylindrical insertion portion 42b protruding downward (in the negative Z-axis direction) from the base portion 42a, and a cylindrical joint portion 42c protruding downward (in the negative Z-axis direction) from the periphery of the base portion 42a.

[0035] 10 , the base 42a is in contact with the base 65a of the negative electrode side second insulating plate 65. The insertion portion 42b is inserted into the insertion hole 65b of the negative electrode side second insulating plate 65, the negative electrode side insertion hole 52b of the lid 52, the insertion hole 63b of the negative electrode side first insulating plate 63, and the insertion hole 22b of the negative electrode current collector plate 22.

[0036] 10 , the joint portion 42c protrudes downward from the insertion hole 22b of the negative current collector plate 22 and is expanded radially outward to be joined to the negative current collector plate 22. That is, the joint portion 42c is crimped to the periphery of the insertion hole 22b of the negative current collector plate 22. Furthermore, the joint portion 42c is welded to the periphery of the insertion hole 22b of the negative current collector plate 22. The negative terminal 42 is formed of, for example, copper or a copper alloy.

[0037] The components of the battery 1 are housed or attached in the exterior body 50. The exterior body 50 shown in Figures 1 to 6 and 10 to 12 includes a container 51, a lid 52, and a sealing plug 53.

[0038] 2 and 6, the container 51 contains the charge / discharge unit 10 covered with an insulating cover 61 and the like. The container 51 is made of a rectangular metal can. As shown in FIG. 6, the container 51 includes an opening 51a that opens along the longitudinal direction and a container portion 51b that is continuous with the opening 51a. The container 51 is made of, for example, aluminum or an aluminum alloy.

[0039] The lid 52 seals the opening 51a of the container 51, as shown in, for example, FIGS. 2 and 6. The lid 52 faces one side 10a (side) of the charge / discharge body 10, where the positive electrode 11, the separator 13, and the negative electrode 12 are adjacent to each other. The lid 52 is formed of a long, plate-shaped metal plate. The lid 52 has a positive electrode side insertion hole 52a formed as a circular through-hole at one end in the longitudinal direction. The insertion portion 41b of the positive electrode terminal 41 is inserted into the positive electrode side insertion hole 52a. The lid 52 has a negative electrode side insertion hole 52b formed as a circular through-hole at the other end in the longitudinal direction. The insertion portion 42b of the negative electrode terminal 42 is inserted into the negative electrode side insertion hole 52b.

[0040] The lid 52 has a liquid inlet 52c formed as a circular through-hole between the positive electrode side insertion hole 52a and the negative electrode side insertion hole 52b. The electrolyte 14 is injected from the lid 52 toward the container 51 through the liquid inlet 52c. An insertion portion 53b of a sealing plug 53 is inserted into the liquid inlet 52c. A split valve 52d is formed in the center of the lid 52 in the longitudinal direction. The lid 52 is welded to the container 51. The lid 52 is made of, for example, aluminum or an aluminum alloy.

[0041] 11, the sealing plug 53 seals the liquid inlet hole 52c of the lid 52. The sealing plug 53 is formed in a cylindrical shape. The sealing plug 53 includes a head portion 53a having a relatively large outer diameter and an insertion portion 53b that is continuous with the head portion 53a and has a relatively small outer diameter. The head portion 53a of the sealing plug 53 is welded to the lid 52. The sealing plug 53 is formed of, for example, aluminum or an aluminum alloy.

[0042] The insulator 60 insulates the components of the battery 1 from the exterior body 50. The insulator 60 shown in Figures 2 to 6, 10, and 12 to 14 includes an insulating cover 61, a positive electrode-side first insulating plate 62, a negative electrode-side first insulating plate 63, a positive electrode-side second insulating plate 64, and a negative electrode-side second insulating plate 65.

[0043] As shown in FIG. 6, the insulating cover 61 covers and insulates the charging / discharging unit 10. The insulating cover 61 includes a pair of opposing side surfaces (a first side surface 61a and a second side surface 61b) and an opening 61c between the first side surface 61a (one side surface) and the second side surface 61b (the other side surface) through which one side portion 10a of the charging / discharging unit 10 is exposed. The insulating cover 61 covers all but one side of the one side portion 10a of the charging / discharging unit 10. That is, the insulating cover 61 covers the other side portion 10b opposite to the one side portion 10a of the charging / discharging unit 10, and the outer periphery portion 10c located between the one side portion 10a and the other side portion 10b of the charging / discharging unit 10. The insulating cover 61 is formed into a pentahedron shape by folding a polyhedron-shaped sheet into a box shape. The insulating cover 61 is made of, for example, polypropylene.

[0044] As shown in FIG. 5, the positive electrode side first insulating plate 62 insulates the positive electrode current collector plate 21 and the conductive member 32 from the lid 52. As shown in FIG. 12, the positive electrode side first insulating plate 62 includes a rectangular parallelepiped base 62a, an insertion hole 62b penetrating the base 62a, and a protrusion 62c annularly extending from the side edge of the base 62a and protruding in a direction away from the surrounding lid 52. As shown in FIG. 14, the positive electrode side first insulating plate 62 includes a positioning pin 62d protruding downward from the base 62a. The positioning pin 62d is inserted into a positioning hole 33d of the support base 33 shown in FIG. 13. The positive electrode side first insulating plate 62 accommodates the positive electrode current collector plate 21, the conductive member 32, and the like in a space defined by the base 62a and the protrusion 62c. The insertion portion 41b of the positive electrode terminal 41 is inserted into the insertion hole 62b. The positive electrode side first insulating plate 62 is formed of, for example, insulating resin.

[0045] As shown in FIG. 3, for example, the negative electrode side first insulating plate 63 insulates the negative electrode current collector plate 22 from the lid 52. As shown in FIG. 10, for example, the negative electrode side first insulating plate 63 includes a rectangular parallelepiped base 63a, an insertion hole 63b penetrating the base 63a, and a protrusion 63c annularly extending from the side edge of the base 63a and protruding in a direction away from the surrounding lid 52. The negative electrode side first insulating plate 63 accommodates the negative electrode current collector plate 22 in a space defined by the base 63a and the protrusion 63c. The insertion portion 42b of the negative electrode terminal 42 is inserted into the insertion hole 63b. The negative electrode side first insulating plate 63 is formed of, for example, insulating resin.

[0046] As shown in FIG. 5, for example, the positive electrode side second insulating plate 64 insulates the positive electrode terminal 41 from the lid 52. As shown in FIG. 12, for example, the positive electrode side second insulating plate 64 includes a rectangular parallelepiped base 64a, an insertion hole 64b penetrating the base 64a, and a protrusion 64c annularly extending from the side edge of the base 64a and protruding in a direction away from the surrounding lid 52. The positive electrode side second insulating plate 64 accommodates the positive electrode terminal 41 in a space defined by the base 64a and the protrusion 64c. The insertion portion 41b of the positive electrode terminal 41 is inserted into the insertion hole 64b. The positive electrode side second insulating plate 64 is formed, for example, from insulating resin.

[0047] As shown in FIG. 3, for example, the negative electrode side second insulating plate 65 insulates the negative electrode terminal 42 from the lid 52. As shown in FIG. 10, for example, the negative electrode side second insulating plate 65 includes a rectangular parallelepiped base 65a, an insertion hole 65b penetrating the base 65a, and a protrusion 65c annularly extending from the side edge of the base 65a and protruding in a direction away from the surrounding lid 52. The negative electrode side second insulating plate 65 accommodates the negative electrode terminal 42 in a space defined by the base 65a and the protrusion 65c. The insertion portion 42b of the negative electrode terminal 42 is inserted into the insertion hole 65b. The negative electrode side second insulating plate 65 is formed of, for example, insulating resin.

[0048] The sealing body 70 seals the components of the battery 1 and the exterior body 50. The sealing body 70 shown in Figures 2 to 5, 10 and 12 includes a positive electrode side gasket 71 and a negative electrode side gasket 72.

[0049] As shown in FIG. 5, for example, the positive electrode side gasket 71 insulates the positive electrode side second insulating plate 64 from the lid 52. The positive electrode side gasket 71 is formed in a cylindrical shape. As shown in FIG. 12, for example, the positive electrode side gasket 71 includes a first insertion portion 71a having a relatively large outer diameter, a second insertion portion 71b continuous with the first insertion portion 71a and having a relatively small outer diameter, and an insertion hole 71c passing through the first insertion portion 71a and the second insertion portion 71b. The first insertion portion 71a of the positive electrode side gasket 71 is inserted into the insertion hole 64b of the positive electrode side second insulating plate 64. The second insertion portion 71b of the positive electrode side gasket 71 is inserted into the positive electrode side insertion hole 52a of the lid 52. The insertion portion 41b of the positive electrode terminal 41 is inserted into the insertion hole 71c. The positive electrode side gasket 71 is formed, for example, from rubber having insulating properties and elasticity.

[0050] As shown in FIG. 3 , the negative electrode side gasket 72 insulates the negative electrode side second insulating plate 65 from the lid 52. The negative electrode side gasket 72 is formed in a cylindrical shape. As shown in FIG. 10 , the negative electrode side gasket 72 includes a first insertion portion 72a with a relatively large outer diameter, a second insertion portion 72b that is continuous with the first insertion portion 72a and has a relatively small outer diameter, and an insertion hole 72c that passes through the first insertion portion 72a and the second insertion portion 72b. The first insertion portion 72a of the negative electrode side gasket 72 is inserted into the insertion hole 65b of the negative electrode side second insulating plate 65. The second insertion portion 72b of the negative electrode side gasket 72 is inserted into the negative electrode side insertion hole 52b of the lid 52. The insertion portion 42b of the negative electrode terminal 42 is inserted into the insertion hole 72c. The negative electrode side gasket 72 is formed, for example, from rubber that has insulating properties and elasticity.

[0051] (Method for manufacturing battery 1 of the first embodiment) A manufacturing method of the battery 1 will be described with reference to Fig. 15 to Fig. 19. Among the manufacturing methods of the battery 1, a manufacturing method specific to the battery 1 of the first embodiment will be described. The manufacturing method specific to the battery 1 of the first embodiment is a manufacturing method corresponding to the first step, the second step, and the third step.

[0052] Before the first step, as shown in FIG. 15, the positive electrode current collector plate 21 and the diaphragm 31 are spaced apart and not joined together.

[0053] 16 and 19, before the first step, a pair of support bases 33 are attached to the positive electrode side first insulating plate 62. The positioning pins 62d of the positive electrode side first insulating plate 62 are inserted into the positioning holes 33d of the support bases 33.

[0054] 16 and 19, before the first step, the positive current collector 21 and the diaphragm 31 are brought closer to each other. Specifically, before the first step, a pressing force P1 is applied to the positive current collector 21 toward the diaphragm 31. The positive current collector 21 is brought closer to the diaphragm 31 than in the state shown in FIG. 15. As a result, the positioning pin 33c of the support base 33 is inserted into the positioning hole 21g of the positive current collector 21. Furthermore, the positive current collector 21 comes into contact with the protrusion 33e of the support base 33.

[0055] In the first step, as shown in FIG. 16 , the relative distance between the positive current collector 21 and the diaphragm 31 is measured. Specifically, in the first step, a laser beam L1 is irradiated onto the surface of the positive current collector 21 near the through-hole 21f of the diaphragm 31. The reflected light of the laser beam L1 is measured to measure the position of the surface of the positive current collector 21. Similarly, in the first step, a laser beam L1 is irradiated onto the surface of the diaphragm 31 through the through-hole 21f of the diaphragm 31 from the side where the charge / discharge body 10 is placed. The reflected light of the laser beam L1 is measured to measure the position of the surface of the diaphragm 31. Next, the distance (C = AB) from the positive current collector 21 to the diaphragm 31 is calculated based on the difference (A) between the surface positions of the positive current collector 21 and the diaphragm 31 and the known thickness (B) of the positive current collector 21. The distance (C = AB) from the positive current collector 21 to the diaphragm 31 corresponds to the gap between the positive current collector 21 and the diaphragm 31. In this manner, the relative distance (C = AB) along the Z-axis direction at the joint T between the positive current collector 21 and the diaphragm 31 is measured.

[0056] In the second step, as shown in FIG. 17 , the support base 33 and the positive current collector plate 21 are brought relatively closer together along the Z-axis direction, and the protrusion 33e of the support base 33 and the positive current collector plate 21 are pressed against each other. The second step is performed simultaneously with or after the first step. Specifically, in the second step, a pressing force P2 is applied to the positive current collector plate 21 toward the support base 33. As a result, the positive current collector plate 21 and the support base 33 are brought relatively closer together along the Z-axis direction than in the state shown in FIG. 16 , and the positive current collector plate 21 and the protrusion 33e are pressed against each other more strongly. The protrusion 33e of the support base 33 has lower rigidity than the positive current collector plate 21 and other parts of the support base 33. Therefore, the protrusion 33e is pressed against the positive current collector plate 21 and other parts of the support base 33, as shown in FIG. 17 , and is plastically deformed. Here, in the first step prior to the second step, the relative distance between the positive current collector 21 and the diaphragm 31 is measured. Therefore, the relative distance between the positive current collector 21 and the diaphragm 31 is adjusted by adjusting the amount of plastic deformation of the protrusion 33e. Specifically, the more the protrusion 33e is plastically deformed, the closer the positive current collector 21 and the diaphragm 31 become. Therefore, the protrusion 33e is plastically deformed so as to eliminate the distance (C = AB) from the positive current collector 21 to the diaphragm 31, i.e., the gap between the positive current collector 21 and the diaphragm 31. In this way, the positive current collector 21 and the diaphragm 31 are changed from the spaced-apart state shown in FIGS. 16 and 19 to the contacting state shown in FIG. 17.

[0057] Before the third step, the positive current collector plate 21 and the support base 33 are joined as shown in FIG. 18. Specifically, before the third step, the tips of the positioning pins 33c of the pair of support bases 33 are heated to soften the tips. At the same time, a pressing force P3 is applied from the tips of the positioning pins 33c toward the positive current collector plate 21. As a result, the tips of the positioning pins 33c are plastically deformed toward the positive current collector plate 21. The positive current collector plate 21 is sandwiched between the tips of the positioning pins 33c and the legs 33b. Thereafter, heating of the tips of the positioning pins 33c is stopped to harden the tips of the positioning pins 33c. In this manner, the positive current collector plate 21 and the support base 33 are joined.

[0058] 18, the positive current collector 21 and the diaphragm 31 are joined together. The third step is performed after the second step. Specifically, in the third step, the joint T between the positive current collector 21 and the diaphragm 31, which are in contact with each other, is laser-welded using, for example, laser light L2.

[0059] (Effects of the Battery 1 and the Manufacturing Method of the Battery 1 of the First Embodiment) The effects of the battery 1 and the method for manufacturing the battery 1 will be described.

[0060] In the battery 1, the protrusion 33e is aligned with the support base 33 along the Z-axis direction and has lower rigidity than the support base 33. In the manufacturing method of the battery 1, in a first step, the distance between the positive current collector plate 21 and the diaphragm 31 is measured along the Z-axis direction. In a second step, the support base 33 and the positive current collector plate 21 are brought relatively close to each other along the Z-axis direction, and the protrusion 33e and the positive current collector plate 21 are pressed against each other. In a third step, after the second step, the positive current collector plate 21 and the diaphragm 31, which are in contact with each other, are joined together. According to the battery 1 and the manufacturing method of the battery 1 configured as described above, the protrusion 33e can be deformed in accordance with manufacturing errors of the components of the battery 1, thereby absorbing manufacturing errors of the components of the battery 1. Examples of the components of the battery 1 include the positive current collector plate 21 and the diaphragm 31. The diaphragm 31 and the like can be joined to the positive current collector plate 21 while maintaining a predetermined shape. Therefore, in the battery 1, the operating pressure of the diaphragm 31 can be kept within a certain range without being affected by manufacturing errors of the components. That is, the diaphragm 31 can be operated as a current cutoff valve with an appropriate operating pressure. This improves the reliability of the battery 1. Furthermore, in the manufacturing method of the battery 1, the positive electrode current collector plate 21 and the diaphragm 31 can be sufficiently joined without being affected by manufacturing errors of the components of the battery 1. This improves the productivity of the battery 1 having the diaphragm 31.

[0061] The protrusion 33e is formed integrally with the support base 33 and protrudes from the support base 33 toward the positive current collector plate 21. The protrusion 33e is configured to be plastically deformable. With the battery 1 configured as described above, the protrusion 33e can be realized with a simple configuration. The protrusion 33e may be formed integrally with the positive current collector plate 21.

[0062] The positive current collector plate 21 has a through-hole 21f that exposes the diaphragm 31 on the side of the charge / discharge body 10. In a first step, the relative distance between the joint T between the positive current collector plate 21 and the diaphragm 31 is measured from the side where the charge / discharge body 10 is disposed, via the through-hole 21f of the positive current collector plate 21. According to the battery 1 and the method for manufacturing the battery 1 configured as described above, the relative distance between the joint T between the positive current collector plate 21 and the diaphragm 31 can be easily measured with a simple configuration that uses the through-hole 21f formed in the positive current collector plate 21. This allows for improved productivity of the battery 1.

[0063] The positive current collector plate 21 has a fragile portion 21e formed around a joint T between the positive current collector plate 21 and the diaphragm 31, the fragile portion 21e having a relatively lower rigidity than the joint T. The manufacturing method of the battery 1 uses the positive current collector plate 21 having the fragile portion 21e formed therein. Even with the battery 1 and the manufacturing method of the battery 1 having such a configuration, the load applied to the fragile portion 21e and the joint T can be reduced by actively deforming the protrusion 33e when joining the current collecting member 20 and the diaphragm 31. In other words, damage to the fragile portion 21e and the joint T during manufacturing of the battery 1 can be reduced. Therefore, in the battery 1, the operating pressure of the diaphragm 31 can be kept within a certain range. In other words, the diaphragm 31 can function properly as a current cutoff valve. Furthermore, in the manufacturing method of the battery 1, the current collecting member 20 and the diaphragm 31 can be sufficiently joined while reducing the load applied to the fragile portion 21e and the joint T. This improves productivity of the battery 1.

[0064] [Second embodiment] (Configuration of Battery 2 of Second Embodiment) The configuration of the battery 2 of the second embodiment will be described with reference to FIG.

[0065] The battery 2 of the second embodiment differs from the battery 1 of the first embodiment in that the protrusion 81 (low-rigidity member) is formed separately from the support base 133 (support member). In the battery 2 of the second embodiment, the same components as those in the battery 1 of the first embodiment are assigned the same reference numerals, and descriptions thereof are omitted. The second embodiment will be described mainly with respect to components different from the first embodiment.

[0066] 20, the support base 133 has the same configuration as the support base 33, except that it does not have the protrusion 81. The support base 133 includes a main body 133a, a pair of legs 133b, a pin 133c, and a positioning hole 133d.

[0067] As shown in FIG. 20 , the protrusions 81 are formed separately from the support base 133. The protrusions 81 are provided between the support base 133 and the positive current collector plate 21. The protrusions 81 are attached to, for example, the positive current collector plate 21. The protrusions 81 protrude in a hemispherical shape from the positive current collector plate 21 toward the leg portions 133b. The protrusions 81 are configured to be plastically deformable. The protrusions 81 have lower rigidity than the positive current collector plate 21 and the leg portions 33b. The protrusions 81 are formed, for example, by dropping a liquid resin onto the positive current collector plate 21 and then hardening it. In this case, the protrusions 81 are configured, for example, from a hemispherical resin member.

[0068] (Method for manufacturing battery 2 of second embodiment) The manufacturing method of the battery 2 is the same as the manufacturing method of the battery 1 of the first embodiment. However, in the second step, the protrusion 81 is pressed by the leg 133b of the support base 133 and the positive current collector plate 21, causing plastic deformation. As a result, the positive current collector plate 21 and the diaphragm 31 come into contact with each other.

[0069] (Effects of Battery 2 of Second Embodiment) The effects of the battery 2 of the second embodiment will be described.

[0070] The protrusion 81 is formed separately from the support base 133 and the positive current collector plate 21. The protrusion 81 is configured to be plastically deformable. The battery 2 configured as described above allows the protrusion 81 to be realized with a simple configuration. That is, similar to the battery 1 of the first embodiment, the battery 2 allows the manufacturing error of the battery 2's components to be absorbed by deforming the protrusion 81 in accordance with the manufacturing error of the battery 2's components. The diaphragm 31 can be joined to the positive current collector plate 21 while maintaining a predetermined shape. The diaphragm 31 and the like can be joined to the positive current collector plate 21 while maintaining a predetermined shape. Therefore, the operating pressure of the diaphragm 31 can be kept within a certain range without being affected by the manufacturing error of the battery 2's components. That is, the diaphragm 31 can function properly as a current cutoff valve. The protrusion 81 is attached to the positive current collector plate 21, for example. The protrusion 81 may also be attached to the support base 133.

[0071] [Third embodiment] (Configuration of battery 3 of third embodiment) The configuration of the battery 3 of the third embodiment will be described with reference to FIG.

[0072] The battery 3 of the third embodiment differs from the battery 1 of the first embodiment in that a protrusion 233e (low-rigidity member) protrudes from the support base 233 (support member) in the direction opposite to the positive current collector plate 21. In the battery 3 of the third embodiment, the same components as those in the battery 1 of the first embodiment are denoted by the same reference numerals, and descriptions thereof will be omitted. The third embodiment will be described mainly with respect to components different from the first embodiment.

[0073] 21, the support base 233 has the same configuration as the support base 33, except that a protrusion 233e protrudes from the support base 233 in the direction opposite to the positive current collector plate 21. The support base 233 includes a main body 233a, a pair of legs 233b, a positioning pin 233c, a positioning hole 233d, and the protrusion 233e.

[0074] The protrusion 233e is formed integrally with the support base 233. The protrusion 233e protrudes from the support base 233 in the direction opposite to the positive current collector plate 21 side. The protrusion 233e protrudes in a hemispherical shape from the support base 233 toward the positive electrode side first insulating plate 62. The protrusion 233e is configured to be plastically deformable. The protrusion 233e has lower rigidity than the positive electrode current collector plate 21 and the main body portion 233a. The protrusion 233e is sandwiched between the support base 233 and the positive electrode side first insulating plate 62.

[0075] (Method for manufacturing battery 3 of the third embodiment) The manufacturing method of the battery 3 is the same as the manufacturing method of the battery 1 of the first embodiment. However, in the second step, the protrusion 233e is pressed by the main body 233a of the support base 233 and the positive electrode side first insulating plate 62, causing plastic deformation. As a result, the positive electrode current collector plate 21 and the diaphragm 31 come into contact with each other.

[0076] (Effects of Battery 3 of Third Embodiment) The effects of the battery 3 of the third embodiment will be described.

[0077] The protrusion 233e protrudes from the support base 233 in the direction opposite to the positive current collector plate 21. The protrusion 233e is configured to be plastically deformable. According to the battery 3 configured as described above, as with the battery 1 of the first embodiment, the manufacturing error of the components of the battery 3 can be absorbed by deforming the protrusion 233e in accordance with the manufacturing error of the components of the battery 3. The diaphragm 31 and the like can be joined to the positive current collector plate 21 while maintaining a predetermined shape. Therefore, the operating pressure of the diaphragm 31 can be kept within a certain range without being affected by the manufacturing error of the components of the battery 3. In other words, the diaphragm 31 can function properly as a current cutoff valve.

[0078] [Fourth embodiment] (Configuration of battery 4 of fourth embodiment) The configuration of the battery 4 of the fourth embodiment will be described with reference to FIG.

[0079] The battery 4 of the fourth embodiment differs from the battery 3 of the third embodiment in that a convex portion 162e (low-rigidity member) is formed on the side of the positive electrode side first insulating plate 162 (covering member). In the battery 4 of the fourth embodiment, the same components as those of the battery 3 of the third embodiment are assigned the same reference numerals, and descriptions thereof are omitted. The fourth embodiment will be described mainly with respect to components different from the third embodiment.

[0080] 22, the support base 333 (support member) has the same configuration as the support base 33, except that the protrusion 162e is not integrally formed. The support base 333 includes a main body 333a, a pair of legs 333b, a positioning pin 333c, and a positioning hole 333d.

[0081] As shown in FIG. 22 , the positive electrode side first insulating plate 162 has the same configuration as the positive electrode side first insulating plate 62, except that a protrusion 162e is formed on the positive electrode side first insulating plate 162. The positive electrode side first insulating plate 162 includes a positioning pin 162d and the like. The protrusion 162e protrudes in a semispherical shape from the positive electrode side first insulating plate 162 toward the support base 333. The protrusion 162e is configured to be plastically deformable. The protrusion 162e has lower rigidity than the other parts of the positive electrode side first insulating plate 162 and the main body 333a. The protrusion 162e is sandwiched between the main body 333a of the support base 333 and the positive electrode side first insulating plate 162.

[0082] (Method for manufacturing battery 4 of the fourth embodiment) The manufacturing method of the battery 4 is the same as the manufacturing method of the battery 1 of the first embodiment. However, in the second step, the protrusion 162e is pressed by the main body 333a of the support base 333 and the positive electrode side first insulating plate 62, causing plastic deformation. As a result, the positive electrode current collector plate 21 and the diaphragm 31 come into contact with each other.

[0083] (Effects of Battery 4 of Fourth Embodiment) The effects of the battery 4 of the fourth embodiment will be described.

[0084] The protrusion 162e is formed on the side of the positive electrode-side first insulating plate 162. The protrusion 162e is configured to be plastically deformable. According to the battery 4 configured in this manner, similar to the battery 3 of the third embodiment, the protrusion 162e can be plastically deformed in accordance with the manufacturing tolerances of the components of the battery 4, thereby absorbing the manufacturing tolerances of the components of the battery 4. The diaphragm 31 and the like can be joined to the positive electrode current collector plate 21 while maintaining a predetermined shape. Therefore, the operating pressure of the diaphragm 31 can be kept within a certain range without being affected by the manufacturing tolerances of the components of the battery 4. In other words, the diaphragm 31 can function properly as a current cutoff valve.

[0085] The battery of the present invention is not limited to the configurations described in the embodiments, but can be configured appropriately based on the contents described in the claims.

[0086] The battery of the present invention is not limited to lithium-ion batteries. The battery of the present invention can be applied to, for example, nickel-metal hydride batteries and lead-acid batteries. The battery of the present invention is not limited to secondary batteries. The battery of the present invention can be applied to primary batteries. The battery of the present invention is not limited to a configuration in which the charging / discharging body is sealed by a container and a lid. The battery of the present invention can be applied to a configuration in which the charging / discharging body is sealed by a laminate film. Each embodiment has been described in detail or simply to clearly explain the present invention, and it is not necessary to include all of the components described, or components not shown may be included. Furthermore, some of the components of one embodiment may be deleted, replaced with components of another embodiment, or combined with components of another embodiment. [Explanation of symbols]

[0087] 1, 2, 3, 4 battery, 10 charging / discharging body, 20 current collecting member, 21 positive electrode current collecting plate (current collecting member), 21e fragile portion, 21f through hole, 30 current interrupter, 31 diaphragm (current interrupting valve), 33 support base (supporting member), 33e convex portion (low rigidity member), 41 positive electrode terminal (external terminal), 62 positive electrode side first insulating plate (covering member), 81 convex portion (low rigidity member), 162e convex portion (low rigidity member), 133 support base (supporting member), 233 support base (supporting member), 233e convex portion (low rigidity member), 333 support base (supporting member), T-joint portion.

Claims

1. A charge / discharge body; a current collecting member that is electrically connected to the charge / discharge body; a current cutoff valve laminated and joined to the current collecting member; an external terminal that is electrically connected to the current cutoff valve; A covering member; a support member that supports the covering member along a stacking direction of the current collecting member and the current cutoff valve; a low-rigidity member that is aligned with the support member along the stacking direction, has lower rigidity than the support member, and is configured to be plastically deformable; and the low-rigidity member is pressed by the current collecting member and the support member and plastically deforms, thereby adjusting the relative distance between the current collecting member and the current cut-off valve; The low-rigidity member is formed integrally with at least one of the support member and the current collecting member, protruding from the support member toward the current collecting member; battery.

2. A charge / discharge body; a current collecting member that is electrically connected to the charge / discharge body; a current cutoff valve laminated and joined to the current collecting member; an external terminal that is electrically connected to the current cutoff valve; A covering member; a support member that supports the covering member along a stacking direction of the current collecting member and the current cutoff valve; a low-rigidity member that is aligned with the support member along the stacking direction, has lower rigidity than the support member, and is configured to be plastically deformable; and the low-rigidity member is pressed by the current collecting member and the support member and plastically deforms, thereby adjusting the relative distance between the current collecting member and the current cut-off valve; The low-rigidity member is formed integrally with or separately from the support member, provided in a direction opposite to the current collecting member from the support member, The covering member sandwiches the low-rigidity member together with the support member. battery.

3. The current collecting member has a through hole formed therein, through which the current cutoff valve is exposed to the charging / discharging body side. The battery according to claim 1 or 2.

4. At least one of the current collecting member and the current cutoff valve has a weak portion formed around a joint between the current collecting member and the current cutoff valve, the weak portion having a relatively lower rigidity than the joint. The battery according to claim 1 or 2.

5. A charge / discharge body; a current collecting member that is electrically connected to the charge / discharge body; a current cutoff valve laminated and joined to the current collecting member; an external terminal that is electrically connected to the current cutoff valve; A covering member; a support member that supports the covering member along a stacking direction of the current collecting member and the current cutoff valve; a low-rigidity member that is aligned with the support member along the stacking direction, has lower rigidity than the support member, and is configured to be plastically deformable; A method for manufacturing a battery having a first step of measuring a distance between the current collecting member and the current cutoff valve along the stacking direction; a second step of pressing the low-rigidity member and the current collecting member together by bringing the support member and the current collecting member relatively close to each other along the stacking direction, simultaneously with or after the first step; a third step of joining the current collecting member and the current cutoff valve that are in contact with each other after the second step; A method for manufacturing a battery having the above structure.

6. the current collecting member has a through hole formed therein to expose the current cutoff valve to the side of the charging / discharging body; In the first step, a relative distance between a joint between the current collecting member and the current cutoff valve is measured through the through hole from a side where the charging / discharging body is disposed. The method for manufacturing the battery according to claim 5 .

7. The current collecting member or the current cutoff valve is used, wherein a weak portion having a relatively lower rigidity than the joint portion is formed around the joint portion between the current collecting member and the current cutoff valve. The method for manufacturing the battery according to claim 5 or 6.

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