Current collector foil for electrodes, electrodes, batteries, methods for manufacturing current collector foil for electrodes, and methods for manufacturing batteries

Abstract

An electrode (a positive electrode 11 and a negative electrode 12) current collecting foil (for example, a positive electrode current collecting layer 11S) has a current collecting portion 11a to which the active material is to be joined and which is to be wound, and a plurality of (for example, 15) terminal portions (for example, positive electrode tabs 11b) provided at the side edge along the winding direction of the current collecting portion 11a. Among the terminal portions adjacent along the winding direction, those closer to one end portion 11p at the winding start of the current collecting portion 11a are formed with a relatively smaller spacing than those closer to the other end portion 11q at the winding end. The plurality of terminal portions overlap each other in a state in which the current collecting portion 11a is wound. At least one of the terminal portions and the current collecting portion 11a is provided with a mark for distinguishing between one terminal portion (for example, the first) of the current collecting portion 11a and the other (for example, the second to fifteenth) terminal portions.

Description

Technical Field

[0005]

[0001] The present invention relates to a current collector foil of an electrode, an electrode, a battery, a method for manufacturing the current collector foil of the electrode, and a method for manufacturing the battery.

Background Art

[0002] Conventionally, a technique for forming a plurality of terminal portions (electrode tabs) on a wound electrode has been known (for example, see Patent Document 1).

Prior Art Documents

Patent Documents

[0008] The present invention provides a method for manufacturing the current collector foil of an electrode, which involves cutting an electrode substrate in which multiple current collector foils of an electrode are connected in a straight line, each having a current collector section to which an active material is joined and wound, and a plurality of terminal sections provided on the side edge along the winding direction of the current collector section. The electrode substrate has the following configuration: The adjacent terminal sections along the winding direction include those in which the spacing is relatively longer on the side closer to the end of the winding of the current collector section than on the side closer to the beginning of the winding. The plurality of terminal sections overlap when the current collector section is wound. At least one of the terminal sections or the current collector section is provided with a mark to distinguish one terminal section of the current collector section from another terminal section. The present invention provides a method for manufacturing an electrode current collector foil, comprising: a first step of transporting the electrode substrate; a second step of forming the mark; and a third step of cutting the electrode substrate in a direction intersecting the transport direction of the electrode substrate based on the mark to form one end and the other end.

[0009] The present invention provides a method for manufacturing a battery, comprising the steps of winding and cutting a positive electrode, a negative electrode, and an insulator provided between the positive electrode and the negative electrode while recognizing at least one of the marks on the positive electrode and the negative electrode. The current collector foil included in at least one of the positive electrode and the negative electrode is the current collector foil manufactured by the method for manufacturing electrode current collector foils. [Effects of the Invention]

[0010] In the wound charge / discharge body of a battery, multiple terminal portions of the electrodes can be properly overlapped. [Brief explanation of the drawing]

[0011] [Figure 1] A perspective view showing battery 1 of the first embodiment. [Figure 2]Cross-sectional perspective view showing the vicinity of the negative electrode terminal 42 of the battery 1 according to the first embodiment. [Figure 3] Cross-sectional view showing the vicinity of the negative electrode terminal 42 of the battery 1 according to the first embodiment. [Figure 4] Cross-sectional perspective view showing the vicinity of the positive electrode terminal 41 of the battery 1 according to the first embodiment. [Figure 5] Cross-sectional view showing the vicinity of the positive electrode terminal 41 of the battery 1 according to the first embodiment. [Figure 6] Exploded perspective view showing the battery 1 according to the first embodiment. [Figure 7] Perspective view showing the charge / discharge body 10 of the battery 1 according to the first embodiment. [Figure 8] Cross-sectional view showing a part of the charge / discharge body 10 of the battery 1 according to the first embodiment. [Figure 9] Cross-sectional view showing a part of the charge / discharge body 110 which is a modification of the battery 1 according to the first embodiment. [Figure 10] Perspective view showing the electrodes (positive electrode 11 and negative electrode 12) and the separator 13 of the battery 1 according to the first embodiment. [Figure 11] Exploded perspective view showing the vicinity of the negative electrode terminal 42 of the battery 1 according to the first embodiment. [Figure 12] Exploded perspective view showing the lid 52 and the sealing plug 53 of the battery 1 according to the first embodiment. [Figure 13] Exploded perspective view showing the vicinity of the positive electrode terminal 41 of the battery 1 according to the first embodiment. [Figure 14] Perspective view showing the method of manufacturing the current collecting foils (positive electrode current collecting layer 11S and negative electrode current collecting layer 12S) of the electrodes (positive electrode 11 and negative electrode 12) of the battery 1 according to the first embodiment. [Figure 15] Perspective view showing the method of manufacturing the charge / discharge body 10 of the battery 1 according to the first embodiment. [Figure 16] Perspective view showing the electrodes (positive electrode 211 and negative electrode 212) and the separator 13 of the battery according to the second embodiment. [Figure 17] Perspective view showing the electrodes (positive electrode 311 and negative electrode 312) and the separator 13 of the battery according to the third embodiment.

Embodiments for Carrying Out the Invention

[0012] Each embodiment of the present invention will be described with reference to the drawings. In order to facilitate understanding of each embodiment, the size and ratio of the constituent members may be exaggerated in the drawings. In FIG. 15, most of the positive electrode tabs 11b and negative electrode tabs 12b are not shown. In each embodiment, the same components are denoted by the same reference numerals and redundant descriptions are omitted. In each embodiment, a left-handed XYZ orthogonal coordinate system with the X-axis, Y-axis, and Z-axis as coordinate axes is used. The arrows on each of the X-axis, Y-axis, and Z-axis indicate the positive directions of the coordinate axes. The X-axis is the coordinate axis in the longitudinal direction of the rectangular battery. The Y-axis is the coordinate axis in the short-side direction of the battery. The Z-axis is the coordinate axis in the height direction of the battery. The plane formed by the X-axis and Y-axis is referred to as the XY plane, the plane formed by the Y-axis and Z-axis is referred to as the YZ plane, and the plane formed by the X-axis and Z-axis is referred to as the XZ plane. However, the positional relationship represented by the XYZ orthogonal coordinate system is only a relative positional relationship.

[0013] [First Embodiment] (Configuration of the current collector foil, electrode, and battery 1 of the first embodiment) The configuration of the current collector foil, electrode, and battery 1 of the first embodiment will be described with reference to FIGS. 1 to 13.

[0014] The battery 1 includes, for example, as shown in FIGS. 1 to 5, a charge / discharge body 10 that charges and discharges electricity, a current collector 20 connected to the charge / discharge body 10, a current cut-off body 30 connected to the current collector 20, an external terminal 40 connected to the current collector 20 or the current cut-off body 30, and an exterior body 50 in which the constituent members of the battery 1 are housed or attached. Further, the battery 1 includes an insulator 60 that insulates the constituent members of the battery between the battery 1 and the exterior body 50, and a sealing body 70 that seals the constituent members of the battery 1 and the exterior body 50. <00001​​​​ The positive electrode 11 includes, for example, a long positive electrode current collector layer 11S (current collector foil) and a positive electrode active material layer 11T bonded to the positive electrode current collector layer 11S, as shown in Figures 7 and 8. The positive electrode current collector layer 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. The positive electrode active material layer 11T faces the entire area along the short direction (Z-axis direction) of the current collector portion 11a, as shown in Figure 8.

[0017] The positive electrode tab 11b (terminal portion) protrudes in the short direction of the current collector 11a from the side edge 11c along the longitudinal direction (winding direction) of the current collector 11a, as shown in Figures 7 and 8, for example. The positive electrode tab 11b is formed integrally with the current collector 11a. Multiple positive electrode tabs 11b are formed on a single current collector 11a.

[0018] The positive electrode tabs 11b are arranged in a so-called unequal pitch. That is, the spacing between adjacent positive electrode tabs 11b (like-polarity terminals adjacent along the winding direction) is relatively longer for adjacent positive electrode tabs 11b closer to the other end 11q of the current collector 11a than for adjacent positive electrode tabs 11b closer to the beginning end 11p of the current collector 11a. All positive electrode tabs 11b are arranged so that the distance between them increases relatively as you move from the end 11p of the current collector 11a to the other end 11q. Therefore, even if the total length of one turn of the positive electrode 11 increases each time the components of the charge / discharge body 10 are wound, all positive electrode tabs 11b will overlap properly when the current collector 11a is wound.

[0019] Here, regarding the spacing between adjacent positive electrode tabs 11b along the winding direction, it is sufficient to include positive electrode tabs 11b in which the spacing between adjacent tabs is relatively longer as you move from one end 11p of the current collector 11a to the other end 11q. In other words, it is not limited to a configuration in which the spacing between adjacent positive electrode tabs 11b along the winding direction is relatively longer as you move from one end 11p of the current collector 11a to the other end 11q. For example, adjacent positive electrode tabs 11b along the winding direction may be configured such that uniform pitch and unequal pitch alternate as you move from one end 11p of the current collector 11a to the other end 11q.

[0020] The positive electrode tab 11d (which is a marker and is one of a plurality of positive electrode tabs 11b) is provided with a marker, as shown in Figure 10. In the first embodiment, the marker is formed by making the shape of the positive electrode tab 11d different from the shape of the other positive electrode tabs 11b. In other words, the marker is an external shape of the positive electrode tab 11d that is different from the other positive electrode tabs 11b. Specifically, as shown in Figure 10, the marker is formed by making the positive electrode tab 11d that is closest to one end 11p of the current collector 11a smaller than the other positive electrode tabs 11b of the current collector 11a.

[0021] Positive electrode tabs 11b and 11d may each be formed in a trapezoidal shape, and a marker may be created by making the ratio of the lengths of the pair of opposite sides (bottom side and top side) different. That is, a marker may be created by making the ratio of the lengths of the bottom side and top side of positive electrode tab 11d (marker) different from the ratio of the lengths of the bottom side and top side of positive electrode tab 11b.

[0022] The corners of the positive electrode tab 11b and the positive electrode tab 11d may be made different in size to form a marker. That is, the corners of the positive electrode tab 11d (marker) and the positive electrode tab 11b may be curved so that the radius of curvature of the corner of the positive electrode tab 11d and the radius of curvature of the corner of the positive electrode tab 11b are different to form a marker.

[0023] Here, the mark on the positive electrode tab 11b only needs to be configured to distinguish one of the multiple positive electrode tabs 11b formed on the current collector 11a from the other positive electrode tabs 11b. In other words, the positive electrode tab 11b with the mark is not limited to the first positive electrode tab 11b located at the beginning of the winding of the current collector 11a. For example, the positive electrode tab 11b with the mark may be the positive electrode tab 11b located at the end of the winding of the current collector 11a, or the positive electrode tab 11b located in the center of the multiple positive electrode tabs 11b formed on the current collector 11a. The other positive electrode tabs 11b are at least one (for example, all) of the multiple positive electrode tabs 11b provided on the positive electrode current collector layer 11S, excluding one of the positive electrode tabs 11b.

[0024] Positive tabs 11b and 11d are examples of terminal sections. The terminal sections may be integrated with the current collector section 11a or may be separate from the current collector section 11a. Multiple terminal sections are provided on the side edges (at least one side edge) of the current collector section 11a along the winding direction (longitudinal direction).

[0025] The current collector 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 composed of a lithium-containing composite oxide, a binder, and a conductive additive. The lithium-containing composite oxide may include, for example, metallic elements such as nickel (Ni), cobalt (Co), and manganese (Mn), along with lithium (Li).

[0026] The negative electrode 12 includes, for example, a long negative electrode current collector layer 12S (current collector foil) and a negative electrode active material layer 12T bonded to the negative electrode current collector layer 12S, as shown in Figures 7 and 8. The negative electrode current collector layer 12S includes a current collector portion 12a and a negative electrode tab 12b. The current collector portion 12a of the negative electrode 12 is wider in the short direction (Z-axis direction) compared to the current collector portion 11a of the positive electrode 11, as shown in Figure 8. Both ends of the current collector portion 11a of the positive electrode 11 are located within the range of the current collector portion 12a of the negative electrode 12, along the short direction, via a separator 13. The 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 along the short direction (Z-axis direction) of the current collector portion 12a.

[0027] The negative electrode tab 12b (terminal portion) protrudes in the short direction of the current collector 12a from the side edge 12c along the longitudinal direction (winding direction) of the current collector 12a, as shown in Figures 7 and 8, for example. 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 collector 12a. Multiple negative electrode tabs 12b are formed on a single current collector 12a.

[0028] The negative electrode tabs 12b, like the positive electrode tabs 11b, are configured with a so-called unequal pitch. That is, the spacing between adjacent negative electrode tabs 12b along the winding direction is relatively longer for negative electrode tabs 12b closer to the other end 12q of the current collector section 12a, than for adjacent negative electrode tabs 12b closer to the starting end 12p of the current collector section 12a. All negative electrode tabs 12b overlap when the current collector section 12a is wound. Here, regarding the spacing of the negative electrode tabs 12b, it is sufficient to include negative electrode tabs 12b in which the spacing between adjacent tabs is relatively longer as you move from the one end 12p of the current collector section 12a towards the other end 12q, similar to the spacing of the positive electrode tabs 11b.

[0029] The negative electrode tab 12d (one of the multiple negative electrode tabs 12b) is provided with a mark, similar to the positive electrode tab 11d, as shown in Figure 10. In the first embodiment, the mark is formed by making the shape of the negative electrode tab 12d different from the shape of the other negative electrode tabs 12d. In other words, the mark is a different external shape of the negative electrode tab 12d compared to the other negative electrode tabs 12b. Specifically, as shown in Figure 10, the mark is formed by making the negative electrode tab 12d located closest to one end 12p of the current collector 12a smaller than the other negative electrode tabs 12b of the current collector 12a.

[0030] The negative electrode tabs 12b and 12d may each be formed in a trapezoidal shape, and a marker may be created by making the ratio of the lengths of the pair of opposite sides (bottom side and top side) different. That is, a marker may be created by making the ratio of the lengths of the bottom side and top side of the negative electrode tab 12d (marker) different from the ratio of the lengths of the bottom side and top side of the negative electrode tab 12b.

[0031] The corners of the negative electrode tab 12b and the negative electrode tab 12d may be made different in size to form a marker. That is, the corners of the negative electrode tab 12d (marker) and the negative electrode tab 12b may be curved so that the radius of curvature of the corner of the negative electrode tab 12d and the radius of curvature of the corner of the negative electrode tab 12b are different to form a marker.

[0032] Here, the markings on the negative electrode tab 12b should be configured to distinguish one of the multiple negative electrode tabs 12b formed on the current collector 12a from the other negative electrode tabs 12b, similar to the positive electrode tab 11b. The other negative electrode tabs 12b refer to at least one (for example, all) of the multiple negative electrode tabs 12b provided on the negative electrode current collector layer 12S, excluding one negative electrode tab 12b.

[0033] The negative electrode tabs 12b and 12d are examples of terminal sections. The terminal sections may be integrated with the current collector section 12a or they may be separate from the current collector section 12a. Multiple terminal sections are provided on the side edges (at least one side edge) of the current collector section 12a along the winding direction (longitudinal direction).

[0034] The current collector 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 composed of a carbon-based material, a binder, and a conductive additive. For example, graphite is used as the carbon-based material.

[0035] The separator 13 (insulator) allows lithium ions to pass through while insulating the space between the positive electrode 11 and the negative electrode 12, as shown in Figures 7 and 8, for example. The separator 13 is formed in a long, rectangular shape. The separator 13 has a longer width in the shorter direction (Z-axis direction) compared to 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 and both ends of the current collector 12a of the negative electrode 12 are located within the range of the separator 13 in the shorter direction. The separator 13 is made of a porous material. Polyethylene (PE) or polypropylene (PP) are used for the separator 13. A heat-resistant insulating material may be used instead of the separator 13. For example, ceramics can be used for the heat-resistant insulating material. This configuration is a so-called separatorless configuration.

[0036] Electrolyte 14 corresponds to a so-called electrolyte solution. Electrolyte 14 is impregnated into the separator 13. Electrolyte 14 contains an organic solvent, a supporting salt, and additives. For example, a carbonate ester is used as the organic solvent. For example, a lithium salt is used as the supporting salt.

[0037] A modified example of the charge / discharge body 10, the charge / discharge body 110, will be described with reference to Figure 9. The configuration of the positive electrode 111 of the charge / discharge body 110 differs from that of the positive electrode 11 of the first embodiment. In the configuration of the charge / discharge body 110, components identical to those of the charge / discharge body 10 are given the same reference numerals and their explanation is omitted. The positive electrode active material layer 111T of the charge / discharge body 110 faces the portion of the current collector 11a excluding both ends along the short direction (Z-axis direction). The heat-resistant insulating layer 111U of the charge / discharge body 110 is bonded to both ends along the short direction of the current collector 11a and to the base end portion of the positive electrode tab 11b. The heat-resistant insulating layer 111U contains, for example, ceramics.

[0038] The current collector 20 is connected to the charge / discharge unit 10. The current collector 20 shown in Figures 2 to 5, 11 and 13 includes a positive electrode current collector plate 21 and a negative electrode current collector plate 22.

[0039] The positive electrode current collector plate 21 connects the positive electrode tab 11b of the charge / discharge body 10 to the positive electrode terminal 41 via a current interrupter 30, as shown in Figures 4 and 5, for example. The positive electrode current collector plate 21 includes a rectangular plate-shaped first base portion 21a, a rectangular 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 Figure 13, for example. A recess 21d is formed on the upper surface (the surface on the positive Z-axis side) of the second base portion 21b, where the thickness of the second base portion 21b is made thinner. A ring-shaped recessed weak portion, the weak portion 21e, is formed in the center of the recess 21d. The positive electrode current collector plate 21 is made of, for example, aluminum or an aluminum alloy.

[0040] The negative electrode current collector plate 22 connects the negative electrode tab 12b of the charge / discharge body 10 to the negative electrode terminal 42, as shown in Figures 2 and 3, for example. The negative electrode current collector plate 22 includes a rectangular plate-shaped base 22a and an insertion hole 22b that penetrates the base 22a, as shown in Figure 11, for example. The insertion portion 42b of the negative electrode terminal 42 is inserted into the insertion hole 22b of the negative electrode current collector plate 22. The negative electrode current collector plate 22 is made of, for example, copper or a copper alloy.

[0041] The current interrupter 30 is connected to the current collector 20, and makes electrical contact between the current collector 20 and the positive terminal 41. The current interrupter 30 shown in Figures 4, 5 and 13 includes a diaphragm 31, a conductive member 32, and a pair of support bases 33.

[0042] The diaphragm 31 includes, for example, a curved cylindrical body portion 31a, a disc-shaped first joint portion 31b provided on the tip side (negative Z-axis side) of the body portion 31a, and a ring-shaped second joint portion 31c provided on the base side (positive Z-axis side) of the body portion 31a. The first joint portion 31b is joined to the recess 21d of the positive electrode current collector plate 21. The second joint portion 31c is joined to the conductive member 32. The diaphragm 31 is formed of, for example, aluminum or an aluminum alloy.

[0043] The conductive member 32 is formed in a cylindrical shape, as shown in Figure 13, for example. The upper surface (the surface on the positive Z-axis side) of the conductive member 32 is joined to the positive electrode side first insulating plate 62. The periphery of the lower surface (the surface on the negative Z-axis side) of the conductive member 32 is joined to the second joint portion 31c of the diaphragm 31. The conductive member 32 is formed of, for example, aluminum or an aluminum alloy.

[0044] The support base 33 includes, for example, a rectangular main body 33a extending in the short direction (Y-axis direction) of the battery 1, and legs 33b extending downward (negative Z-axis direction) from both sides of the main body 33a in the longitudinal direction (Y-axis direction). One support base 33 is provided at each end of the diaphragm 31 along the longitudinal direction (X-axis direction) of the battery 1. The main body 33a is attached to the positive electrode side first insulating plate 62. The legs 33b are attached to the second base 21b of the positive electrode current collector plate 21. The support base 33 is formed of, for example, an insulating resin.

[0045] The external terminal 40 is connected to the current collector 20 or the current interrupter 30. The external terminal 40 shown in Figures 1 to 6, 11 and 13 includes a positive terminal 41 and a negative terminal 42.

[0046] The positive terminal 41 is connected to the conductive member 32 of the current interrupter 30, for example, as shown in Figure 5. The positive terminal 41 includes a rectangular 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.

[0047] The base portion 41a is in contact with the base portion 64a of the positive electrode side second insulating plate 64, for example, as shown in Figure 13. 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 cover 52, the insertion hole 62b of the positive electrode side first insulating plate 62, and the insertion hole 32b of the conductive member 32.

[0048] The joint portion 41c protrudes downward (in the negative Z-axis direction) from the insertion hole 32b of the conductive member 32, as shown in Figure 13, for example, and is expanded radially outward to join with 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.

[0049] The negative electrode terminal 42 is connected to the negative electrode current collector plate 22, for example, as shown in Figure 3. The negative electrode terminal 42 includes a rectangular 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.

[0050] The base portion 42a is in contact with the base portion 65a of the negative electrode side second insulating plate 65, for example, as shown in Figure 11. 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 cover 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.

[0051] The joint portion 42c protrudes downward from the insertion hole 22b of the negative electrode current collector plate 22, as shown in Figure 11, for example, and is expanded radially outward to join with the negative electrode current collector plate 22. That is, the joint portion 42c is crimped to the periphery of the insertion hole 22b of the negative electrode current collector plate 22. Furthermore, the joint portion 42c is welded to the periphery of the insertion hole 22b of the negative electrode current collector plate 22. The negative electrode terminal 42 is formed of, for example, copper or a copper alloy.

[0052] The outer casing 50 houses or mounts the components of the battery 1. The outer casing 50 shown in Figures 1 to 6 and Figures 11 to 13 includes a container 51, a lid 52, and a sealing plug 53.

[0053] The container 51 houses a charge / discharge unit 10 covered by an insulating cover 61, as shown in Figures 2 and 6, for example. The container 51 is made of a rectangular metal can. The container 51 includes an opening 51a that opens along the longitudinal direction and a housing section 51b connected to the opening 51a, as shown in Figure 6, for example. The container 51 is made of aluminum or an aluminum alloy, for example.

[0054] The lid 52 seals the opening 51a of the container 51, as shown in Figures 2 and 6, for example. The lid 52 faces one side 10a (side portion) of the charge / discharge body 10 where the positive electrode 11, separator 13, and negative electrode 12 are adjacent. The lid 52 is formed from a long, plate-shaped metal sheet. The lid 52 has a positive electrode side insertion hole 52a, which is 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, which is 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.

[0055] The lid 52 has an injection hole 52c formed by 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 injection hole 52c. The insertion portion 53b of the sealing plug 53 is inserted into the injection hole 52c. The lid 52 has a splitting valve 52d formed in the longitudinal center. The lid 52 is welded to the container 51. The lid 52 is made of, for example, aluminum or an aluminum alloy.

[0056] The sealing plug 53 seals the liquid injection hole 52c of the lid 52, for example, as shown in Figure 12. The sealing plug 53 is formed in a cylindrical shape. The sealing plug 53 includes a head 53a with a relatively large outer diameter and an insertion portion 53b that is continuous with the head 53a and has a relatively smaller outer diameter. The head 53a of the sealing plug 53 is welded to the lid 52. The sealing plug 53 is made of, for example, aluminum or an aluminum alloy.

[0057] The insulator 60 insulates the components of the battery 1 from the outer casing 50. The insulator 60 shown in Figures 2 to 6, 11 and 13 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.

[0058] The insulating cover 61 insulates the charge / discharge element 10 by covering it, as shown in Figure 6, for example. The insulating cover 61 has a pair of opposing sides (first side 61a and second side 61b) and an opening 61c between the first side 61a (one side) and the second side 61b (the other side) that exposes one side 10a of the charge / discharge element 10. The insulating cover 61 covers all sides of one side 10a of the charge / discharge element 10 except for one side. That is, the insulating cover 61 covers the other side 10b of the charge / discharge element 10 that is opposite to the first side 10a, and the outer periphery 10c located between the first side 10a and the other side 10b of the charge / discharge element 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.

[0059] 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 Figure 5, for example. The positive electrode side first insulating plate 62 includes a rectangular plate-shaped base portion 62a, an insertion hole 62b that penetrates the base portion 62a, and a protrusion 62c that surrounds the side edge of the base portion 62a in an annular shape and protrudes away from the lid 52, as shown in Figure 13, for example. The positive electrode side first insulating plate 62 houses the positive electrode current collector plate 21 and the conductive member 32, etc., in the space formed by the base portion 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, an insulating resin.

[0060] The negative electrode side first insulating plate 63 insulates the negative electrode current collector plate 22 from the cover 52, as shown in Figure 3, for example. The negative electrode side first insulating plate 63 includes a rectangular plate-shaped base portion 63a, an insertion hole 63b that penetrates the base portion 63a, and a protrusion 63c that surrounds the side edge of the base portion 63a in an annular shape and protrudes away from the cover 52, as shown in Figure 11, for example. The negative electrode current collector plate 22 is housed in the space formed by the base portion 63a and the protrusion 63c of the negative electrode side first insulating plate 63. 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, an insulating resin.

[0061] The positive electrode side second insulating plate 64 insulates the positive electrode terminal 41 from the cover 52, as shown in Figure 5, for example. The positive electrode side second insulating plate 64 includes a rectangular plate-shaped base 64a, an insertion hole 64b that penetrates the base 64a, and a protrusion 64c that surrounds the side edge of the base 64a in an annular shape and protrudes away from the cover 52, as shown in Figure 13, for example. The positive electrode terminal 41 is housed in the space formed by the base 64a and the protrusion 64c of the positive electrode side second insulating plate 64. 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 of, for example, an insulating resin.

[0062] The negative electrode side second insulating plate 65 insulates the negative electrode terminal 42 from the cover 52, for example, as shown in Figure 3. The negative electrode side second insulating plate 65 includes a rectangular plate-shaped base 65a, an insertion hole 65b that penetrates the base 65a, and a protrusion 65c that surrounds the side edge of the base 65a in an annular shape and protrudes away from the cover 52, for example, as shown in Figure 11. The negative electrode terminal 42 is housed in the space formed by the base 65a and the protrusion 65c of the negative electrode side second insulating plate 65. 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, an insulating resin.

[0063] The sealing body 70 seals the components of the battery 1 and the outer casing 50. The sealing body 70 shown in Figures 2 to 5, 11 and 13 includes a positive electrode gasket 71 and a negative electrode gasket 72.

[0064] The positive electrode gasket 71 insulates the positive electrode second insulating plate 64 from the lid 52, as shown in Figure 5, for example. The positive electrode gasket 71 is formed in a cylindrical shape. The positive electrode gasket 71 includes a first insertion portion 71a with a relatively large outer diameter, a second insertion portion 71b that is continuous with the first insertion portion 71a and has a relatively smaller outer diameter, and an insertion hole 71c that penetrates the first insertion portion 71a and the second insertion portion 71b, as shown in Figure 13, for example. The first insertion portion 71a of the positive electrode gasket 71 is inserted into the insertion hole 64b of the positive electrode second insulating plate 64. The second insertion portion 71b of the positive electrode gasket 71 is inserted into the positive electrode 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 gasket 71 is formed of, for example, rubber that has insulating and elastic properties.

[0065] The negative electrode gasket 72 insulates the negative electrode second insulating plate 65 from the lid 52, as shown in Figure 3, for example. The negative electrode gasket 72 is formed in a cylindrical shape. The negative electrode 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 smaller outer diameter, and an insertion hole 72c that penetrates the first insertion portion 72a and the second insertion portion 72b, as shown in Figure 11, for example. The first insertion portion 72a of the negative electrode gasket 72 is inserted into the insertion hole 65b of the negative electrode second insulating plate 65. The second insertion portion 72b of the negative electrode gasket 72 is inserted into the negative electrode 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 gasket 72 is formed of, for example, rubber that has insulating and elastic properties.

[0066] (Method for manufacturing the electrode current collector foil and battery 1 of the first embodiment) The current collector foil for the electrodes and the manufacturing method of the battery 1 according to the first embodiment will be described with reference to Figures 14 and 15. Here, the manufacturing method for the current collector foil for the electrodes will be described in terms of the manufacturing method for the multiple positive electrode tabs 11b, including the positive electrode tab 11d which serves as a marker and is a configuration unique to the first embodiment. The manufacturing method for the multiple negative electrode tabs 12b, including the negative electrode tab 12d which serves as a marker, is the same as the manufacturing method for the multiple positive electrode tabs 11b, including the positive electrode tab 11d which serves as a marker, so the description will be omitted.

[0067] The manufacturing method for the positive electrode current collector layer 11S (current collector foil) of the positive electrode 11 of the battery 1 shown in Figure 14 includes a first step of transporting the positive electrode first substrate 11J (electrode substrate) and a second step of forming a positive electrode tab 11d (marker) on the positive electrode first substrate 11J.

[0068] As shown in Figure 14, the electrode tab manufacturing apparatus 500 includes a controller 501, an unloading roller 502, a first winding roller 503, a second winding roller 504, a first laser processing machine 505, a second laser processing machine 506, and a third laser processing machine 507.

[0069] The electrode tab manufacturing apparatus 500 laser-processes the positive electrode first substrate 11J to form a plurality of positive electrode tabs 11b, including a positive electrode tab 11d that serves as a marker. The controller 501 controls the operation of the discharge roller 502, the first winding roller 503, the second winding roller 504, the first laser processing machine 505, the second laser processing machine 506, and the third laser processing machine 507. The positive electrode first substrate 11J is elongated and formed by bonding a positive electrode active material layer 11T to a positive electrode current collector layer 11S. On the positive electrode first substrate 11J, the positive electrode active material layer 11T shown in Figures 7 and 8 is not bonded to a pair of side edges along the longitudinal direction, and the positive electrode current collector layer 11S is exposed. The positive electrode first substrate 11J is wound around the discharge roller 502, which has a cylindrical cross-section.

[0070] The controller 601 operates the first winding roller 503 and the second winding roller 504. The operation of the first winding roller 503 and the second winding roller 504 causes the positive electrode first substrate 11J, which has been discharged from the discharge roller 502, to move toward the first laser processing machine 505, the second laser processing machine 506, and the third laser processing machine 507. The first laser processing machine 505 scans one side edge of the positive electrode first substrate 11J along its longitudinal direction while irradiating it with laser light L1. The laser light L1 cuts and discards the portion of the positive electrode first substrate 11J corresponding to the space between adjacent positive electrode tabs 11b along one side edge along its longitudinal direction. As a result, a marker positive electrode tab 11d and positive electrode tab 11b are formed on one side edge along the longitudinal direction of the positive electrode first substrate 11J. The multiple positive electrode tabs 11b are formed at unequal pitches. One positive electrode tab 11d is formed at each length that makes up a single positive electrode 11. The second laser processing machine 506 scans the other side edge along the longitudinal direction of the positive electrode first substrate 11J while irradiating it with laser light L2. The laser light L2 cuts and discards the portion corresponding to the space between adjacent positive electrode tabs 11b along the other side edge along the longitudinal direction of the positive electrode first substrate 11J. As a result, a positive electrode tab 11d and a positive electrode tab 11b are formed on the other side edge along the longitudinal direction of the positive electrode first substrate 11J.

[0071] The third laser processing machine 507 irradiates the center of the moving positive electrode first substrate 11J with laser light L3. The laser light L3 cuts the positive electrode first substrate 11J into two, forming a pair of positive electrode second substrates 11K. Of the pair of positive electrode second substrates 11K, one is wound up by the first winding roller 503. Of the pair of positive electrode second substrates 11K, the other is wound up by the second winding roller 504. In other words, the positive electrode first substrate 11J is cut in the middle, forming two positive electrode second substrates 11K. On each positive electrode second substrate 11K, one side edge along the longitudinal direction has multiple positive electrode tabs 11b formed, including a positive electrode tab 11d that serves as a marker. Furthermore, in each positive electrode second substrate 11K, the other side edge along the longitudinal direction is in a state where the positive electrode current collector layer 11S and the positive electrode active material layer 11T are connected, as shown in Figures 7 and 8.

[0072] The manufacturing method for the positive electrode current collector layer 11S (current collector foil) of the positive electrode 11 of the battery 1 shown in Figure 15 includes a third step of cutting the positive electrode second substrate 11K (electrode substrate) in a direction intersecting the transport direction based on the positive electrode tab 11d to form one end 11p and the other end 11q. Furthermore, the manufacturing method for the charge / discharge body 10 constituting the battery 1 shown in Figure 15 includes a step of winding the positive electrode 11, the negative electrode 12, and the separator 13 while recognizing the markings on the positive electrode 11 and the negative electrode 12.

[0073] As shown in Figure 15, the winding device 600 includes a controller 601, a feed roller 602, a driven roller 603, a first discharge roller 604, a second discharge roller 605, a first camera 606, a first adjustment roller 607, a first driven roller 608, a cutter 609, a cutter support 610, a second camera 611, a second adjustment roller 612, a second driven roller 613, and a winding spindle 614.

[0074] The winding device 600 is equipped with a first winding roller 503 on which the positive electrode second base material 11K is wound, and a second winding roller 504 on which the negative electrode second base material 12K is wound.

[0075] The winding device 600 winds the material while recognizing the markings on the positive electrode 11 and the negative electrode 12 to form the charge / discharge body 10. The controller 601 controls the operation of the first winding roller 503, the second winding roller 504, the delivery roller 602, the first discharge roller 604, the second discharge roller 605, the first camera 606, the first adjustment roller 607, the cutter 609, the second camera 611, the second adjustment roller 612, and the winding spindle 614.

[0076] The first adjustment roller 607 and the first driven roller 608 are positioned between the feed roller 602 and the first winding roller 503. The first camera 606 is positioned near the first adjustment roller 607. The second adjustment roller 612 and the second driven roller 613 are positioned between the feed roller 602 and the second winding roller 504. The second camera 611 is positioned near the second adjustment roller 612. The cutter 609 and the cutter support 610 are positioned between the feed roller 602 and the winding spindle 614.

[0077] The controller 601 activates the feed roller 602. As the feed roller 602 is activated, the positive electrode second substrate 11K discharged from the first winding roller 503, the separator substrate 13K discharged from the first discharge roller 604, the negative electrode second substrate 12K discharged from the second winding roller 504, and the separator substrate 13K discharged from the second discharge roller 605 move toward the cutter 609 and the cutter support 610. The positive electrode second substrate 11K, the separator substrate 13K, the negative electrode second substrate 12K, and the separator substrate 13K are stacked in that order and move toward the cutter 609 and the cutter support 610 while being sandwiched between the feed roller 602 and the driven roller 603.

[0078] The controller 601 activates the first camera 606 to photograph the positive electrode second substrate 11K. Based on the image of the positive electrode second substrate 11K that has been photographed, the controller 601 determines whether the position of the positive electrode tab 11d formed on the positive electrode second substrate 11K is at the position corresponding to the starting position of winding the positive electrode 11 in the charge / discharge body 10. If the controller 601 determines that the position of the positive electrode tab 11d is not at the corresponding position, it determines that the position of the positive electrode tab 11d at the starting position of winding the positive electrode second substrate 11K is misaligned and adjusts the position of the positive electrode tab 11d. The controller 601 activates the first adjustment roller 607 to move the positive electrode second substrate 11K, which is sandwiched between the first adjustment roller 607 and the first driven roller 608, toward the cutter 609 and the cutter support 610. After the position of the positive electrode tab 11d at the start of winding of the positive electrode second substrate 11K is adjusted by the first adjustment roller 607, an excess portion of the positive electrode second substrate 11K protrudes from the feed roller 602 and the driven roller 603. The controller 601 operates the cutter 609 and, together with the cutter support 610, cuts off the excess portion of the positive electrode second substrate 11K. Under the control of the controller 601, the starting position of winding of the positive electrode second substrate 11K relative to the charge / discharge body 10 is adjusted using the positive electrode tab 11d corresponding to the starting position of winding as a guide.

[0079] The controller 601 activates the second camera 611 to photograph the negative electrode second substrate 12K. Based on the image of the negative electrode second substrate 12K that has been photographed, the controller 601 determines whether the position of the negative electrode tab 12d formed on the negative electrode second substrate 12K is at the position corresponding to the starting position of winding the negative electrode 12 in the charge / discharge body 10. If the controller 601 determines that the position of the negative electrode tab 12d is not at the corresponding position, it determines that the position of the negative electrode tab 12d at the starting position of winding the negative electrode second substrate 12K is misaligned and adjusts the position of the negative electrode tab 12d. The controller 601 activates the second adjustment roller 612 to move the negative electrode second substrate 12K, which is sandwiched between the second adjustment roller 612 and the second driven roller 613, toward the cutter 609 and the cutter support 610. After the position of the negative electrode tab 12d at the start of winding of the negative electrode second substrate 12K is adjusted by the second adjustment roller 612, an excess portion of the negative electrode second substrate 12K protrudes from the feed roller 602 and the driven roller 603. The controller 601 operates the cutter 609 to cut the excess portion of the negative electrode second substrate 12K together with the cutter support 610. Under the control of the controller 601, the starting position of winding of the negative electrode second substrate 12K relative to the charge / discharge body 10 is adjusted using the negative electrode tab 12d corresponding to the starting position of winding as a guide.

[0080] The controller 601 operates the feed roller 602 to feed the stacked positive electrode second substrate 11K, separator substrate 13K, negative electrode second substrate 12K, and separator substrate 13K toward the winding spindle 614. The controller 601 operates the winding spindle 614 to wind the stacked positive electrode second substrate 11K, separator substrate 13K, negative electrode second substrate 12K, and separator substrate 13K. The positive electrode second substrate 11K, separator substrate 13K, negative electrode second substrate 12K, and separator substrate 13K are wound by the winding spindle 614 to form one charge / discharge body 10. The controller 601 operates the cutter 609 to cut the ends of the wound positive electrode second substrate 11K, separator substrate 13K, negative electrode second substrate 12K, and separator substrate 13K.

[0081] Subsequently, the charge / discharge unit 10 is removed from the winding spindle 614. The charge / discharge unit 10 is placed in the container 51. The lid 52 is attached to the container 51. The electrolyte 14 is injected into the container 51 through the injection hole 52c of the lid 52. The electrolyte 14 impregnates the separator 13. The sealing plug 53 is attached to the injection hole 52c of the lid 52.

[0082] (Current collector foil for the electrode, electrode, battery 1, method for manufacturing the current collector foil for the electrode, and effects of the method for manufacturing the battery 1 according to the first embodiment) The current collector foil of the electrode, the electrode, the battery 1, the method for manufacturing the current collector foil of the electrode, and the effects of the method for manufacturing the battery 1 of the first embodiment will be explained with reference to Figures 7, 8, 10, 14, and 15. In particular, the effects of the markings formed on the positive electrode 11 will be explained first. The configuration and effects of the markings formed on the negative electrode 12 are the same as those of the markings formed on the positive electrode 11.

[0083] In battery 1, for example, the positive electrode current collector layer 11S (current collector foil) of the positive electrode 11 (electrode) is provided with a mark to distinguish one positive electrode tab 11b of the current collector section 11a from the other positive electrode tabs 11b. Furthermore, in the manufacturing method of the positive electrode current collector layer 11S of the positive electrode 11 of battery 1, for example, the mark is formed. Furthermore, in the manufacturing method of battery 1, the positive electrode 11, the negative electrode 12, and the separator (insulator) are wound while recognizing the mark.

[0084] With this configuration, it is possible to prevent the position of the positive electrode tab 11d at the beginning of winding of the positive electrode 11 from shifting in the charge / discharge body 10 of the battery 1. Therefore, multiple positive electrode tabs 11b of the positive electrode 11 can be properly overlapped in the charge / discharge body 10. The charge / discharge body 10 of the battery 1 is composed of a positive electrode 11, a separator 13, and a negative electrode 12 wound together. Therefore, by properly overlapping multiple positive electrode tabs 11b, the battery 1 can meet the expected battery performance. Furthermore, with this configuration, in the manufacturing method of the battery 1, the cutting position of the positive electrode 11 can be correctly recognized based on the markings. In addition, in the manufacturing of the positive electrode current collector layer 11S of the positive electrode 11 and the manufacturing method of the battery 1, when manufacturing is stopped for any reason and then resumed, the cutting position of the positive electrode 11 can be correctly recognized based on the markings. Furthermore, when forming the positive electrode tab 11b on the positive electrode first substrate 11J (electrode substrate), if manufacturing is stopped for any reason and then resumed, the state of the formed positive electrode tab 11b can be correctly recognized based on the markings.

[0085] The markers are formed in the positive electrode 11 so that the positive electrode tab 11d (the first one) closest to one end 11p (the starting point of the winding) of the current collector portion 11a and the other positive electrode tabs 11b (for example, the second to the fifteenth, a total of 14) can be distinguished. In the manufacturing method of the positive electrode current collector layer 11S of the positive electrode 11, the above-mentioned markers are formed in the second step. That is, the first positive electrode tab 11d, which is closest to one end 11p of the current collector portion 11a and is the easiest to distinguish, is used as the marker. With this configuration, the markers can be formed based on a simple and easily distinguishable method.

[0086] The marker is the outer shape of the positive electrode tab 11d (the first one) closest to one end 11p (the starting point of the winding) of the current collector portion 11a of the positive electrode 11, and is different in shape from the other positive electrode tabs 11b (for example, the second to the fifteenth, a total of 14). In the manufacturing method of the positive electrode current collector layer 11S of the positive electrode 11, the above marker is formed in the second step. With this configuration, the marker can be formed by the outer shape of the positive electrode tab 11d, which is simple and easy to distinguish.

[0087] In the positive electrode 11, the positive electrode tabs 11d and 11b may be formed in a trapezoidal shape. In this case, in the positive electrode 11, for example, the positive electrode tab 11d closest to one end 11p of the current collector 11a and the other positive electrode tabs 11b will have different ratios of the lengths of opposite sides in the trapezoidal shape. With such a configuration, the marker positive electrode tab 11d and the multiple positive electrode tabs 11b can be distinguished by slight differences in their external shape. Furthermore, the marker positive electrode tab 11d and the multiple positive electrode tabs 11b can be manufactured separately without increasing the manufacturing time.

[0088] In the positive electrode 11, the positive electrode tabs 11d and 11b may have different sizes of curved corners. In this case, for example, in the positive electrode 11, the positive electrode tab 11d closest to one end 11p of the current collector 11a and the other positive electrode tabs 11b may have different radii of curvature of their corners. With such a configuration, the marker positive electrode tab 11d and the multiple positive electrode tabs 11b can be distinguished by slight differences in their external shape. Furthermore, the marker positive electrode tab 11d and the multiple positive electrode tabs 11b can be manufactured separately without increasing the manufacturing time.

[0089] In the first embodiment, the configuration and effects of the positive electrode tab 11d (marker) formed on the positive electrode 11 were described above. The configuration and effects of the negative electrode tab 12d (marker) formed on the negative electrode 12 are the same as those of the positive electrode tab 11d (marker) formed on the positive electrode 11.

[0090] [Second Embodiment] (Configuration of the mark formed on the electrode in the second embodiment) The configuration of the mark formed on the positive electrode 211 of the second embodiment will be described with reference to Figure 16.

[0091] In the second embodiment, recesses (recesses 211e and 212e) formed on the electrode tabs (positive electrode tab 211b and negative electrode tab 212b) are used as markers. The second embodiment will be described in detail, focusing on the recess 211e formed on the positive electrode tab 211b, which corresponds to the marker on the positive electrode side. In the second embodiment, the structure and manufacturing method of the recess 212e of the negative electrode tab 21bb are the same as those of the recess 211e of the positive electrode tab 211b, so the explanation will be omitted.

[0092] In the positive electrode 211, the marker is formed on the positive electrode tab 211d, which is the closest of the multiple positive electrode tabs 211b to one end 211p of the current collector 211a. A concave recess 211e is formed on the positive electrode tab 211d as a marker. The recess 211e is formed in a circular shape, for example, in the center of the positive electrode tab 211d. The recess 211e may also be formed at the end of the positive electrode tab 211d, avoiding the joint between the positive electrode tab 211d and the multiple positive electrode tabs 211b.

[0093] Here, the markings on the positive electrode tab 211b only need to be configured to distinguish one of the multiple positive electrode tabs 211b formed on the current collector 11a from the other positive electrode tabs 211b. In other words, the positive electrode tab 211b with the markings is not limited to the first positive electrode tab 211b located at the beginning of the winding of the current collector 211a. For example, the positive electrode tab 211b with the markings may be the positive electrode tab 211b located at the end of the winding of the current collector 211a, or the positive electrode tab 211b located in the center of the multiple positive electrode tabs 211b formed on the current collector 211a.

[0094] (Method for manufacturing a mark formed on an electrode in the second embodiment) A method for manufacturing the mark formed on the positive electrode 211 of the second embodiment will be described with reference to Figure 16.

[0095] The marker depression 211e is formed as a melting mark created by partially concavely indenting the positive electrode tab 211d by irradiating it with laser light. The depression 211e is formed when the positive electrode tab 211d is formed by the laser light L1 of the first laser processing machine 505 or the laser light L2 of the second laser processing machine 506, using the laser light of a laser processing machine with lower power than the first laser processing machine 505 or the second laser processing machine 506. Alternatively, the depression 211e is formed by the laser light L1 of the first laser processing machine 505 or the laser light L2 of the second laser processing machine 506 while the positive electrode tab 211d is being formed. In this case, the output of the laser light L1 of the first laser processing machine 505 or the laser light L2 of the second laser processing machine 506 is sufficiently reduced.

[0096] The marker, the recessed portion 211e, may be formed as an indentation created by pressing the positive electrode tab 211d with a convex jig, thereby partially concavening the positive electrode tab 211d.

[0097] (Effect of the mark formed on the electrode in the second embodiment) The effect of the mark formed on the positive electrode 211 of the second embodiment will be explained with reference to Figure 16.

[0098] The marker is, for example, a recess 211e formed on the positive electrode tab 211d of the positive electrode 211. With this configuration, the marker can be formed by a simple and easily distinguishable recess 211e.

[0099] The depression 211e is a laser mark or an indentation. With this configuration, the shape and depth of the mark can be arbitrarily set using a highly versatile method.

[0100] In the second embodiment, the configuration and effects of the recess 211e (marker) formed on the positive electrode tab 211b were described above. The configuration and effects of the recess 212e (marker) formed on the negative electrode tab 212b are the same as those of the recess 211e (marker) formed on the positive electrode tab 211b.

[0101] [Third Embodiment] (Configuration of the mark formed on the electrode in the third embodiment) The configuration of the mark formed on the positive electrode 311 of the third embodiment will be described with reference to Figure 17.

[0102] In the third embodiment, notches (notches 311f and 312f) formed in the current collector section 311a adjacent to the electrode tabs (positive electrode tab 311b and negative electrode tab 312b) are used as markers. The third embodiment will be described in detail, focusing on the notch 311f formed in the current collector section 311a, which corresponds to the marker on the positive electrode side. In the third embodiment, the configuration and manufacturing method of the notch 312f, which corresponds to the marker on the negative electrode 312, are the same as those of the notch 311f, which corresponds to the marker on the positive electrode 311, so the explanation will be omitted.

[0103] As shown in Figure 17, the marker is formed as a notch 311f in the current collector portion 311a of the positive electrode 311, adjacent to the first positive electrode tab 311d that is closest to one end 311p of the current collector portion 311a. The notch 311f is formed by cutting out a rectangular shape in the portion of the current collector portion 311a that is located at the base of the positive electrode tab 311d. The notch 311f may also be formed by cutting out a semicircular or groove-shaped portion of the current collector portion 311a that is located at the base of the positive electrode tab 311d. The notch 311f is formed on one side of the base of the positive electrode tab 311d in the current collector portion 311a. The notch 311f may also be formed on both sides of the base of the positive electrode tab 311d in the current collector portion 311a.

[0104] Here, the mark provided on the current collector 311a only needs to be configured to distinguish one of the multiple positive electrode tabs 311b formed on the current collector 11a from the other positive electrode tabs 311b. In other words, the notch 311f of the mark is not limited to being formed in the portion adjacent to the base of the first positive electrode tab 311b closest to one end 311p. For example, the mark provided on the current collector 311a may be formed in the portion adjacent to the base of the positive electrode tab 311b located at the end of the winding of the current collector 311a, or in the portion adjacent to the base of the central positive electrode tab 311b among the multiple positive electrode tabs 311b formed on the current collector 311a. The notch 311f of the mark is not limited to being formed in the portion at the base of the positive electrode tab 311d. For example, the notched portion 311f of the marker may be formed between two adjacent positive electrode tabs 311b among the multiple positive electrode tabs 311b formed on the current collector portion 311a.

[0105] The markings are not limited to a notched portion 311f formed by partially cutting out the current collector portion 311a. For example, the markings may be formed by partially recessing or groove-shaped depressions on the surface of the current collector portion 311a.

[0106] The marker is formed on the current collector portion 311a, for example, on the part where the positive electrode active material layer is not bonded. Therefore, the marker does not affect the electrical characteristics of the battery.

[0107] (Method for manufacturing a mark formed on an electrode in the third embodiment) A method for manufacturing the mark formed on the positive electrode 311 of the third embodiment will be described with reference to Figure 17, etc.

[0108] The notch 311f, which serves as a marker, is formed together with the positive electrode tab 311d when forming the positive electrode tab 311d on the positive electrode first substrate in the manufacturing method shown in Figure 14. That is, the positive electrode tab 311d and the notch 311f are formed simultaneously by irradiating the side edges of the positive electrode first substrate with laser beams L1 and L2 and cutting them.

[0109] (Effect of the mark formed on the electrode in the third embodiment) The effect of the mark formed on the positive electrode 311 of the third embodiment will be explained with reference to Figure 17.

[0110] The marker is, for example, a notch 311f formed by partially cutting out the current collector portion 311a in the positive electrode 311. With this configuration, the marker can be formed by a notch 311f that is simple to construct and easy to distinguish. Furthermore, with this configuration, the notch 311f can be formed together with the positive electrode tab 311d, making it easy to form the notch 311f.

[0111] The notch 311f is formed, for example, in the positive electrode 311, in the portion adjacent to the positive electrode tab 311d that is closest to one end 311p of the current collector portion 311a. With this configuration, the starting position of the winding of the positive electrode 311 relative to the charge / discharge body 10 can be easily adjusted using the notch 311f, which is located near the positive electrode tab 311d corresponding to the starting position of the winding of the positive electrode 311, as a guide.

[0112] In the third embodiment, the configuration and effects of the notch 311f (marker) formed in the current collector portion 311a of the positive electrode 311 were described. The configuration and effects of the notch 312f (marker) formed in the current collector portion 312a of the negative electrode 312 are the same as those of the notch 311f (marker) formed in the current collector portion 311a of the positive electrode 311.

[0113] The battery of the present invention is not limited to the configuration described in the embodiments, but can be appropriately configured based on the content described in the claims.

[0114] 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 charge / discharge unit is sealed by a container and a lid. The battery of the present invention can be applied to a configuration in which the charge / discharge unit is sealed by a laminate film. Each embodiment is described in detail or in a simplified manner to illustrate the present invention, and it is not necessary to have all the described configurations, or it may have configurations that are not shown. Also, some of the configurations of one embodiment may be deleted, replaced with configurations of other embodiments, or combined with configurations of other embodiments. [Explanation of Symbols]

[0115] 1 Battery, 11 Positive electrode, 11J Positive electrode first substrate (electrode substrate), 11K Positive electrode second substrate (electrode substrate), 11S Positive electrode current collector layer (current collector foil), 11a Current collector part, 11b Positive electrode tab (terminal part), 11c Side edge, 11d Positive electrode tab (marker), 11p One end, 12 Negative electrode, 12J Negative electrode first substrate (electrode substrate), 12K Negative electrode second substrate (electrode substrate), 12S Negative electrode current collector layer (current collector foil), 12a Current collector part, 12b Negative electrode tab (terminal part), 12c Side edge, 12d Negative electrode tab (marker), 12p One end, 13 Separator (insulator), 14 Electrolyte, 211 Positive electrode, 211a Current collector part, 211b Positive electrode tab (terminal part), 211d Positive electrode tab (terminal part), 211e Recess (mark), 211p One end, 212 Negative electrode (electrode), 212a Current collector, 212b Negative electrode tab (terminal part), 212d Negative electrode tab (terminal part), 212e Recess (mark), 212p One end, 311 Positive electrode (electrode), 311a Current collector, 311b Positive electrode tab (terminal part), 311d Positive electrode tab (terminal part), 311f Notch (mark), 311p One end, 312 Negative electrode (electrode), 312a Current collector, 312b Negative electrode tab (terminal part), 312d Negative electrode tab (terminal part), 312f Notch (mark), 312p One end

Claims

1. An electrode comprising a current collector foil having a current collector portion on which an active material is joined and wound, and a plurality of terminal portions provided on the side edge along the winding direction of the current collector portion, in a battery comprising said electrode, The adjacent terminal portions along the winding direction include those in which the spacing is relatively longer on the side closer to the end of the winding than on the side closer to the beginning of the winding of the current collector portion. The multiple terminal portions overlap when the current collector is wound around them. At least one of the terminal portion or the current collector portion is provided with a mark that distinguishes one of the terminal portions of the current collector portion from the other terminal portion. The terminal portion is formed in a trapezoidal shape, The terminal portion closest to one end of the current collector and the other terminal portions have different ratios of the lengths of the pairs of opposite sides in the trapezoidal shape. Current collector foil.

2. The current collector section in which the active material is joined and wound, Multiple terminal portions are provided on the side edge of the current collector along the winding direction, It has, The adjacent terminal portions along the winding direction include those in which the spacing is relatively longer on the side closer to the end of the winding than on the side closer to the beginning of the winding of the current collector portion. The multiple terminal portions overlap when the current collector is wound around them. At least one of the terminal portion or the current collector portion is provided with a mark that distinguishes one of the terminal portions of the current collector portion from the other terminal portion. The terminal portion is formed in a rectangular shape having at least one curved corner, A current collector foil in which the terminal portion closest to one end of the current collector portion and the other terminal portions differ in the degree of curvature at the corner.

3. The current collector section in which the active material is joined and wound, The current collector section has a plurality of terminal portions provided on the side edge along the winding direction, The adjacent terminal portions along the winding direction include those in which the spacing is relatively longer on the side closer to the end of the winding than on the side closer to the beginning of the winding of the current collector portion. The multiple terminal portions overlap when the current collector is wound around them. At least one of the terminal portion or the current collector portion is provided with a mark that distinguishes one of the terminal portions of the current collector portion from the other terminal portion. The aforementioned mark is a concave recess formed in the terminal portion. Current collector foil.

4. The aforementioned depression is a laser mark or an indentation. The electrode current collector foil according to claim 3.

5. The current collector section in which the active material is joined and wound, The current collector section has a plurality of terminal portions provided on the side edge along the winding direction, The adjacent terminal portions along the winding direction include those in which the spacing is relatively longer on the side closer to the end of the winding than on the side closer to the beginning of the winding of the current collector portion. The multiple terminal portions overlap when the current collector is wound around them. At least one of the terminal portion or the current collector portion is provided with a mark that distinguishes one of the terminal portions of the current collector portion from the other terminal portion. The aforementioned mark is formed by partially cutting out the current collection portion. Current collector foil.

6. The aforementioned mark is formed in the current collector portion on the portion adjacent to the terminal portion that is closest to one end of the current collector portion. The electrode current collector foil according to claim 5.

7. A current collector foil for an electrode according to any one of claims 1 to 6, An electrode having an active material bonded to the current collector foil.

8. Positive electrode and, The negative electrode and, An insulator provided between the positive electrode and the negative electrode, The electrolyte impregnated in the insulator, It has, At least one of the positive electrode and the negative electrode is the electrode described in claim 7. battery.

9. A method for manufacturing a current collector foil according to any one of claims 1 to 6, The first step involves transporting an electrode substrate in which multiple current-collecting foils of the aforementioned electrodes are arranged in a straight line, A second step of forming the mark on the electrode substrate, A third step is to cut the electrode substrate in a direction intersecting the transport direction of the electrode substrate based on the aforementioned markings to form one end and the other end, A method for manufacturing a current collector foil having an electrode.

10. In the second step, the mark is formed so that the terminal portion closest to one end of the current collector portion and the other terminal portions can be distinguished. A method for manufacturing the current collector foil of an electrode according to claim 9.

11. In the second step, the mark is formed which has an external shape that is different from the external shape of the other terminals that is closest to one end of the current collector. A method for manufacturing an electrode current collector foil according to claim 9 or 10.

12. The process includes winding a positive electrode, a negative electrode, and an insulator provided between the positive electrode and the negative electrode while recognizing at least one of the marks on the positive electrode and the negative electrode. The current collector foil included in at least one of the positive electrode and the negative electrode is manufactured by the method for manufacturing electrode current collector foils described in any one of claims 9 to 11. Battery manufacturing method.

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