battery

Abstract

Provided is a battery capable of improving structural reliability. A battery includes a power generation element and a current collecting terminal. The power generation element includes a plurality of current collecting tabs arranged in a thickness direction. The current collecting terminal is joined to the current collecting tabs. At least one of the current collecting tabs has at least one slit that divides an end portion of the current collecting tab in a width direction. Each portion of the end portion of the current collecting tab that is divided by the slit is electrically connected to another current collecting tab adjacent in the thickness direction.

Description

Technical Field

[0001] This application relates to batteries. Background Technology

[0002] Patent Document 1 discloses a joining method for joining a laminated structure and a metal plate disposed at the end of the laminated structure. The laminated structure is composed of multiple metal foils and multiple insulating films. The joining method includes: a first step of fabricating a laminated structure by alternately stacking metal foils with slits at the ends and insulating films; a second step of contacting the metal plate with the slit ends of the laminated structure and aligning and bending the ends of the metal foils in contact with the metal plate in the stacking direction; and a third step of welding the ends of the metal foils and the metal plate together while the ends of the metal foils in contact with the metal plate are aligned and bent in the stacking direction.

[0003] According to the joining method described in Patent Document 1, the following effects are expected: The end of the metal foil is aligned and bent in a predetermined direction by the metal plate. Furthermore, a laser is moved along the direction in which the end of the metal foil is aligned and bent. As a result, the extension of the end of the metal foil in this direction due to thermal expansion is promoted. Simultaneously, even if the end of the metal foil is about to separate from the metal plate due to the impact of the molten metal plate, the end of the metal foil is pressed against the metal plate. Therefore, gaps are less likely to form between the end of the metal foil and the metal plate, and the welding of the metal foil and the metal plate can be performed with a stable welding result and fewer welding defects. As a result, the welding strength between the metal foil and the metal plate can be ensured.

[0004] Existing technical documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2011-129328 Summary of the Invention

[0006] In conventional batteries, the current collector tabs are individually connected to the current collector terminals, which can lead to a problem where power cannot be extracted from certain electrodes in the event of poor soldering. This issue is unique to batteries using electrode laminates in power generation elements. Therefore, a battery with improved structural reliability is desired to avoid this problem.

[0007] Therefore, in view of the above, the purpose of this disclosure is to provide a battery that can improve structural reliability.

[0008] As a solution to the above-mentioned problems, this disclosure provides a battery having a power generation element and a current collector terminal. The power generation element includes a plurality of current collector tabs arranged in the thickness direction. The current collector terminal is engaged with the current collector tabs. At least one current collector tab has at least one slit that divides the end of the current collector tab in the width direction. The portions of the end of the current collector tab that are divided by the slit are electrically connected to other current collector tabs adjacent to each other in the thickness direction.

[0009] In the aforementioned battery, the portion of the end of the current collector tab that is divided by a slit can also be electrically connected to other current collector tabs disposed at different positions in the thickness direction. Additionally, each current collector tab may have at least one slit, and the portions of the end of the current collector tab that are divided by the slit can also be electrically connected to the portions of the ends of other adjacent current collector tabs in the thickness direction. Furthermore, the portions of the ends of the current collector tabs and the portions of the ends of other current collector tabs can also be electrically connected by bending them inwards together to make contact.

[0010] In the battery of this disclosure, the portions of the current collector tabs, separated by slits, are electrically connected to other current collector tabs adjacent to each other in the thickness direction. Then, in this state, the current collector tabs are engaged with the current collector terminals. Therefore, even if a portion of the joint between these electrically connected current collector tabs and current collector terminals becomes poorly connected, these current collector tabs and current collector terminals remain electrically connected via other joints. That is, power can be extracted from the power generation element without electrically isolating the power generation element with poorly soldered current collector tabs. Therefore, the battery according to this disclosure improves structural reliability. Attached Figure Description

[0011] Figure 1 (A) A three-dimensional view of battery 100. Figure 1 (B) is an exploded perspective view of battery 100.

[0012] Figure 2 It is along Figure 1 (B) Schematic diagram of the cross section cut by line II-II.

[0013] Figure 3 This is a three-dimensional view of the negative collector tab 11b.

[0014] Figure 4 (A) is from Figure 3 The frontal view observed by IVA. Figure 4 (B) is along Figure 3 A cross-sectional view of the IVB-IVB line cut off. Figure 4 (C) is along Figure 3 A cross-sectional view of the IVC-IVC line cut off.

[0015] Figure 5 Is with Figure 4 (B) Figure 4 (C) The corresponding cross-sectional views are cross-sectional views when the negative collector terminal 20b is connected to the negative collector ear 11b.

[0016] Figure 6 (A) is a front view of another configuration of the negative collector tab 11b. Figure 6 (B) is along Figure 6 (A) Cross-sectional view of the VIB-VIB line cut. Figure 6 (C) is along Figure 6 (A) Cross-sectional view of the VIC-VIC line cut.

[0017] Figure 7 (A) is a front view of another configuration of the negative collector tab 11b. Figure 7 (B) is along Figure 7 (A) Cross-sectional view of line VIIB-VIIB cut. Figure 7 (C) is along Figure 7 (A) Cross-sectional view of line VIIC-VIIC cut.

[0018] Figure 8 This is a schematic diagram showing the state of each step in a battery manufacturing method according to one embodiment.

[0019] Explanation of reference numerals in the attached figures

[0020] 10 power generation components

[0021] 11 Negative current collector layer

[0022] 11a negative electrode plate section

[0023] 11b negative collector ear

[0024] 11c slit

[0025] Part 11d

[0026] 12 negative electrode active material layers

[0027] 13 Solid Electrolyte Layer

[0028] 14 Positive Electrode Active Material Layer

[0029] 15 Positive Current Collector Layer

[0030] 15a Positive Plate Section

[0031] 15b Positive Collector Ear

[0032] 16-electrode body

[0033] 20a negative collector terminal

[0034] 20b positive collector terminal

[0035] 100 batteries Detailed Implementation

[0036] [Battery]

[0037] The battery of this disclosure will be described with reference to battery 100 as one embodiment. Figure 1 (A) shows a perspective view of battery 100. Figure 1 (B) shows an exploded perspective view of battery 100. Figure 2 Show along Figure 1 (B) Schematic diagram of the cross section cut by line II-II.

[0038] like Figure 1 (A) and Figure 1 As shown in (B), the battery 100 includes a power generation element 10 and current collector terminals (negative current collector terminal 20a and positive current collector terminal 20b). The power generation element 10 includes a plurality of current collector tabs (negative current collector tab 11b and positive current collector tab 15b) arranged in the thickness direction, and the current collector terminals are connected to the current collector tabs. Furthermore, in Figure 1 (A) and Figure 1 In (B), each collector tab is arranged on the same surface of the power generation element 10, but the present invention is not limited thereto, and each collector tab may also be arranged on different surfaces of the power generation element 10. The same applies to the arrangement of the collector terminals.

[0039] <Power Generation Component 10>

[0040] The power generation element 10 is the power generation component of the battery. It can be a laminate formed by stacking electrodes or a wound body formed by winding electrodes. There is no particular limitation on the type of power generation element 10; it can be a power generation element for liquid-state batteries or a power generation element for all-solid-state batteries. In addition, there is no particular limitation on the shape of the power generation element 10; for example, it can be rectangular when viewed from above. Figure 1 The example shown is a battery 100 including a power generation element 10, which is a laminate of electrodes for a solid-state battery. Hereinafter, the power generation element 10, which is a laminate of electrodes for a solid-state battery, will be described. However, the structure of the power generation element 10 is not limited to this.

[0041] The power generation element 10 sequentially comprises a negative electrode current collector layer 11, a negative electrode active material layer 12, a solid electrolyte layer 13, a positive electrode active material layer 14, and a positive electrode current collector layer 15 in the thickness direction. The power generation element 10 can have multiple electrode bodies 16 in the thickness direction, where the negative electrode current collector layer 11, negative electrode active material layer 12, solid electrolyte layer 13, positive electrode active material layer 14, and positive electrode current collector layer 15 are considered as a repeating unit (electrode body 16). The electrode bodies 16 can be stacked in series or in parallel. Furthermore, when the power generation element 10 has multiple electrode bodies 16, adjacent electrode bodies 16 can share either the positive electrode current collector layer 11 or the negative electrode current collector layer 15. Figure 1 The diagram shows a power generation element 10 having multiple electrode bodies 16.

[0042] (Negative electrode current collector layer 11)

[0043] The negative electrode current collector layer 11 is a sheet-like metal foil. The negative electrode current collector layer 11 includes a negative electrode plate portion 11a in contact with the negative electrode active material layer 12 and negative electrode current collector tabs 11b extending outward from the negative electrode plate portion 11a. The negative electrode current collector tabs 11b are components for connecting the negative electrode plate portion 11a and the negative electrode current collector terminal 40a. The negative electrode plate portion 11a and the negative electrode current collector tabs 11b can be constituted by a single component or by separate components. When the power generation element 10 has multiple electrode bodies 16, the negative electrode current collector tabs 11b can also be arranged in a straight line in the thickness direction.

[0044] The metal constituting the negative electrode current collector layer 11 is not particularly limited, and examples include Cu, Ni, Cr, Au, Pt, Ag, Al, Fe, Ti, Zn, Co, and stainless steel. Cu is preferred. The negative electrode current collector layer 11 may have some coating (e.g., carbon coating) on ​​its surface for adjusting resistance. The thickness of the negative electrode current collector layer 11 may be, for example, 0.1 μm or more and 1 mm or less.

[0045] (Negative electrode active material layer 12)

[0046] The negative electrode active material layer is a sheet-like layer containing negative electrode active material. There are no particular limitations on the type of negative electrode active material. Examples include silicon and Si alloys, silicon-based active materials such as silicon oxide, carbon-based active materials such as graphite and hard carbon, various oxide-based active materials such as lithium titanate, metallic lithium, and lithium alloys.

[0047] The negative electrode active material layer 12 may optionally include a conductive additive, a binder, and a solid electrolyte. The type of conductive additive is not particularly limited. Examples include carbon materials such as acetylene black and Ketjen black, and metal materials such as nickel, aluminum, and stainless steel. The type of binder is not particularly limited. Examples include butadiene rubber (BR), butene rubber (IIR), acrylate butadiene rubber (ABR), and polyvinylidene fluoride (PVdF). The type of solid electrolyte is not particularly limited. For example, it can be an organic polymer electrolyte or an inorganic solid electrolyte. An inorganic solid electrolyte is preferred because it has higher ionic conductivity and better heat resistance compared to organic polymer electrolytes. The inorganic solid electrolyte can be an oxide solid electrolyte or a sulfide solid electrolyte. A sulfide solid electrolyte is preferred. Examples of oxide solid electrolytes include lithium lanthanum zirconate, LiPON, and Li 1+X Al X Ge 2-X (PO4)3, Li-SiO glass, Li-Al-SO glass, etc. Examples of sulfide solid electrolytes include Li2S-P2S5, Li2S-SiS2, LiI-Li2S-SiS2, LiI-Si2S-P2S5, Li2S-P2S5-LiI-LiBr, LiI-Li2S-P2S5, LiI-Li2S-P2O5, LiI-Li3PO4-P2S5, and Li2S-P2S5-GeS2.

[0048] The content of each component in the negative electrode active material layer 12 can be appropriately set according to the purpose. The thickness of the negative electrode active material layer can be, for example, greater than 0.1 μm and less than 1 mm.

[0049] (Solid electrolyte layer 13)

[0050] The solid electrolyte layer 13 is a sheet-like layer containing a solid electrolyte. The type of solid electrolyte is not particularly limited and can be appropriately selected from solid electrolytes suitable for use in the negative electrode active material layer.

[0051] The solid electrolyte layer 13 may optionally include a binder. There is no particular limitation on the type of binder; it may be appropriately selected from binders suitable for use in the negative electrode active material layer.

[0052] The content of each component in the solid electrolyte layer 13 can be appropriately set according to the purpose. The thickness of the solid electrolyte layer 13 can be, for example, greater than 0.1 μm and less than 1 mm.

[0053] (Positive electrode active material layer 14)

[0054] The positive electrode active material layer 14 is a sheet-like layer containing positive electrode active material. The type of positive electrode active material is not particularly limited. Examples include various lithium-containing composite oxides such as lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel cobalt oxide, lithium nickel cobalt manganese oxide, and spinel-based lithium compounds.

[0055] The positive electrode active material layer may optionally include conductive additives, binders, and solid electrolytes. There are no particular limitations on the types of conductive additives, binders, and solid electrolytes; appropriate selections can be made from those suitable for use in the negative electrode active material layer.

[0056] The content of each component in the positive electrode active material layer 14 can be appropriately set according to the purpose. Alternatively, the surface of the positive electrode active material can be coated with an oxide layer such as lithium niobate, lithium titanate, or lithium phosphate. The thickness of the positive electrode active material layer 14 can be, for example, 0.1 μm or more and 1 mm or less.

[0057] (Positive current collector layer 15)

[0058] The positive current collector layer 15 is a sheet-like metal foil. The positive current collector layer 15 includes a positive electrode plate portion 15a in contact with the positive electrode active material layer 14 and positive electrode current collector tabs 15b extending outward from the positive electrode plate portion 15a. The positive electrode current collector tabs 15b are components for connecting the positive electrode plate portion 15a and the positive electrode current collector terminal 40b. The positive electrode plate portion 15a and the positive electrode current collector tabs 15b can be constituted by a single component or by separate components. When the power generation element 10 has multiple electrode bodies 16, the positive electrode current collector tabs 15b can also be arranged in a straight line in the thickness direction.

[0059] The metal constituting the positive current collector layer 15 is not particularly limited, and examples include Cu, Ni, Cr, Au, Pt, Ag, Al, Fe, Ti, Zn, Co, and stainless steel. Al is preferred. The positive current collector layer 15 may have some coating (e.g., carbon coating) on ​​its surface for adjusting resistance. The thickness of the positive current collector layer 15 may be, for example, 0.1 μm or more and 1 mm or less.

[0060] (Morphology of the collector ear)

[0061] The current collector tab of battery 100 has a characteristic shape. Hereinafter, the characteristic shape of the current collector tab will be described with reference to the negative current collector tab 11b. However, the characteristic shape of the current collector tab can also be applied to the positive current collector tab 15b. Therefore, the following description also applies to the positive current collector tab 15b.

[0062] Figure 3 A three-dimensional view of the negative collector tab 11b is shown. Figure 4 (A) shows from Figure 3 Frontal view of IVA observation. Figure 4 (B) shows along Figure 3 A cross-sectional view of the IVB-IVB line cut off. Figure 4 (C) shows along Figure 3 A cross-sectional view of the IVC-IVC line cut off. Additionally, Figure 5 (A) Figure 5 (B) Showing the negative collector ear 11b connected to the negative collector terminal 20b Figure 4 (B) Figure 4 (C) shows the corresponding cross-sectional views. Here, in Figure 3 In the diagram, the X direction is the extension direction (the direction in which the collector tab extends), the Y direction is the width direction (the width direction of the collector tab), and the Z direction is the thickness direction (the thickness direction of the collector tab). They are orthogonal to each other.

[0063] like Figure 3 , Figure 4 As shown in (A) to 4(C), a plurality of negative electrode collector ears 11b are arranged in the thickness direction. Furthermore, each negative electrode collector ear 11b has three slits 11c that divide the end (the outer end in the extending direction) of the negative electrode collector ear 11b in the width direction. Thus, the end of each negative electrode collector ear 11b is divided into four parts 11d.

[0064] Each portion 11d of the end of the negative electrode collector ear 11b, which is divided by a slit, is electrically connected to the portion 11d of the end of another negative electrode collector ear 11b adjacent to it in the thickness direction, which is also divided by a slit 11c. At this time, the portion 11d of the end of the negative electrode collector 11b, which is divided by the slit 11c, is electrically connected to other negative electrode collector ears 11b located at different positions in the thickness direction. Furthermore, a portion 11d of an adjacent negative electrode collector ear 11b is connected to other portions 11d of the negative electrode collector ear 11b by bending their ends (particularly the tip portion) together inwards.

[0065] Thus, the battery 100 has negative electrode collector tabs 11b in the form of each end 11d being wound in, such as... Figure 4 As indicated by the arrow in (A), each negative collector tab 11b is electrically connected. Furthermore, as... Figure 5 (A) Figure 5 As shown in (B), each portion 11d of the negative collector tab 11b is connected to the negative collector terminal 20a. Figure 5 (A) Figure 5 In (B), the joint portion is represented by B.

[0066] The battery 100 has negative electrode collector tabs 11b with this characteristic shape, and each negative electrode collector tab 11b is electrically connected. Therefore, even if a part of the joint between the negative electrode collector tab 11b and the negative electrode current collector terminal 20a is poorly joined, the negative electrode collector tab 11b and the negative electrode current collector terminal 20a are still electrically connected via other joints. That is, power can be extracted from each electrode body 16 without electrically isolating the electrode body 16 with the poorly joined negative electrode collector tab 11b. Therefore, the structural reliability of the battery 100 can be improved.

[0067] The shape of the slit 11c of the negative electrode collector tab 1b is not particularly limited; the end of the negative electrode collector tab 11b can be divided. Figure 3 In this design, slit 11c is a straight cut along its extension direction. The length of slit 11c in the extension direction is not particularly limited, as long as it is the length that allows each portion 11d of the negative collector tab 11b separated by slit 11c to connect with other negative collector tabs 11b. Furthermore, the lengths of each slit 11c can be the same or different. The number of slits 11c in the negative collector tab 11b is not particularly limited, but at least one is required. Figure 3 The diagram shows a negative collector tab 11b with three slits 11c. Furthermore, the number of slits 11c in each negative collector tab 11b may be the same or different.

[0068] There are no particular limitations on the method of electrical connection between adjacent negative electrode collector tabs 11b in the thickness direction. Figure 3 In this configuration, the portions 11d of the negative collector tab 11b are electrically connected through direct contact, but they can also be electrically connected via, for example, a conductive member. There is no particular limitation on the number of portions 11d of the negative collector tab 11b that are electrically connected. It is permissible for three or more portions 11d of the negative collector tab 11b (especially the tip portions) to be bent together for electrical connection. Figure 3 The diagram shows the configuration where portions 11d of the two negative collector tabs 11b are bent together and electrically connected. Additionally, Figure 3 In this structure, the various parts 11d are electrically connected by bending them together inwards to make contact, but the connection method is not limited to this. For example, the parts may simply make contact without bending. Furthermore, the direction in which the ends 11d are bent together is not particularly limited; it may be one side or the other side of the thickness direction, or a mixture of both. Additionally, as... Figure 3 As shown, there may also be negative collector ears 11b that are not connected to the adjacent negative collector ears 11b. In this case, the negative collector ears 11b that are not connected to the adjacent negative collector ears 11b may also be bent in order to facilitate connection to the negative collector terminal 20a.

[0069] The method of joining the negative collector tab 11b to the negative collector terminal 20a is not particularly limited, and known methods can be appropriately used. For example, joining methods such as soldering, ultrasonic bonding, or laser welding can be employed. Furthermore, Figure 5 (A) Figure 5 In (B), the overlapping portions of the ends 11d are joined together, but the present invention is not limited thereto. The number of joined portions is not particularly limited; there can be at least one. As described above, each of the wound negative collector ears 11b is electrically connected.

[0070] Next, another configuration of the negative collector tab 11b will be described. Figure 3 In the present invention, each negative electrode current collector tab 11b has a slit 11c, but the battery disclosed herein is not limited to this, and at least one negative electrode current collector tab 11b may have a slit. For example, in a battery with five negative electrode current collector tabs 11b arranged in the thickness direction, the method of having a slit 11c only from the third negative electrode current collector tab 11b from the top will be described. Figure 6 (A) shows a front view of this method. Figure 6 (B) shows along Figure 6 (A) Cross-sectional view of VIB-VIB line cut off. Figure 6 (C) shows along Figure 6 (A) Cross-sectional view of the VIC-VIC line cut.

[0071] like Figure 6 (A)~ Figure 6 As shown in (C), a portion 11d of the ends 11d of the negative electrode collector ears 11b, which are separated by the slit 11c, is electrically connected to other adjacent negative electrode collector ears 11b in the thickness direction. The other portion 11d is electrically connected to other adjacent negative electrode collector ears 11b in the thickness direction. Thus, each end 11d of the negative electrode collector ear 11b with the slit 11c is wound into the adjacent negative electrode collector ear 11b, as... Figure 6 As indicated by the arrow in (A), the negative collector ear 11b with slit 11c is electrically connected to each adjacent negative collector ear 11b via end 11d.

[0072] Therefore, even if a portion of the connection between the negative current collector tabs 11b (one set of negative current collector tabs) and the negative current collector terminal 20a becomes poorly joined, the one set of negative current collector tabs 11b and the negative current collector terminal 20a can still be electrically connected via other connection portions. That is, in the one set of negative current collector tabs 11b, power can be extracted from all electrode bodies 16 without electrically isolating the electrode body with the poorly joined negative current collector tab 11b. Therefore, the battery 100 with this configuration of negative current collector tabs 11b can improve structural reliability.

[0073] Furthermore, another method of negative electrode collector tab 11b will be described. Figure 3 In this embodiment, the end portions 11d of the negative electrode collector tab 11b, which are separated by a slit 11c, are electrically connected to the end portions 11d of other negative electrode collector tabs 11b located at different positions in the thickness direction. However, the battery disclosed herein is not limited to this, and each portion 11d may also be electrically connected to the same other negative electrode collector tab 11b. For example, in a group of four negative electrode collector tabs 11b arranged in the thickness direction, the second and third negative electrode collector tabs 11b from the top are described in such a way that the slit 11c is present. Figure 7 (A) shows a front view of this method. Figure 7 (B) shows along Figure 7 (A) Cross-sectional view of line VIIB-VIIB cut off. Figure 7 (C) shows along Figure 7 (A) Cross-sectional view of line VIIC-VIIC cut.

[0074] like Figure 7 (A)~ Figure 7 As shown in (C), the portions 11d of the ends of the negative electrode collector ears 11b, which are separated by the slit 11c, are electrically connected to the portions 1d of the ends of the other negative electrode collector ears 11b. Therefore, even if a portion of the joint between these electrically connected negative electrode collector ears 11b (one set of negative electrode collector ears) and the negative electrode current collector terminal 20a becomes poorly joined, the one set of negative electrode collector ears 11b and the negative electrode current collector terminal 20a can still be electrically connected via other joints. That is, in one set of negative electrode collector ears 11b, power can be extracted from the entire electrode body 16 without electrically isolating the electrode body with the poorly joined negative electrode collector ears 11b. Therefore, the battery 100 with this configuration of negative electrode collector ears 11b can improve structural reliability.

[0075] <Collider Terminal>

[0076] The collector terminal is a component used to connect the power generation element 10 and external components. The negative collector terminal 40a is connected to the negative collector tab 11b, and the positive collector terminal 40b is connected to the positive collector tab 15b. The material of the terminal is not particularly limited, and can be appropriately selected from metal materials that can be used for the negative collector terminal 40a or the positive collector terminal 40b.

[0077] <Other Components>

[0078] Battery 100 can be stored in the outer casing. There are no particular limitations on the type of outer casing; for example, metal laminates such as Al laminates and metal frames such as metal cans can be used.

[0079] [Battery manufacturing method]

[0080] Next, the method for manufacturing the battery disclosed herein will be described. The method for manufacturing the battery disclosed herein is not particularly limited, and known methods can be used. Hereinafter, one embodiment of the method for manufacturing a battery having a power generation element, which is a laminate formed by stacking electrodes for an all-solid-state battery, will be described.

[0081] One embodiment of the battery manufacturing method includes: an electrode fabrication step S1, a slit application step S2, an electrode stacking step S3, a current collector ear winding step S4, and a current collector terminal bonding step S5. Figure 8 It is a schematic diagram showing the status of each process.

[0082] <Electrode fabrication process S1>

[0083] Electrode fabrication step S1 is the process of fabricating the negative electrode and the positive electrode. The negative electrode and the positive electrode can be fabricated using known methods. For example, the material constituting the negative electrode active material layer can be dispersed in an organic solvent, the resulting slurry can be coated onto the negative electrode current collector layer and dried to obtain the negative electrode. The positive electrode can be obtained using the same method.

[0084] The solid electrolyte layer can be fabricated by laminating it onto one of the negative electrode and the positive electrode, or it can be fabricated separately from these electrodes. For example, the solid electrolyte layer can be laminated onto the negative electrode by dispersing the material constituting the solid electrolyte layer in an organic solvent, coating it onto the surface of the negative electrode active material layer of the negative electrode, and then drying it. Alternatively, the solid electrolyte layer can be fabricated separately and placed between the positive electrode and the negative electrode in the electrode lamination process S3.

[0085] Here, the negative and positive electrodes used inside the laminate can form electrode layers on both sides.

[0086] <Slit application process S2>

[0087] The slit-applying process S2 is the process of applying slits to each collector tab. As a slit-applying method, a known method can be appropriately applied. For example, it is sufficient to simply cut the collector tab to have slits.

[0088] <Electrode stacking process S3>

[0089] Electrode lamination process S3 is a process of fabricating a laminate by laminating negative and positive electrodes. There are no particular limitations on the lamination method for each electrode; known methods can be appropriately used. Furthermore, after fabricating the laminate, pressure can be applied to the laminate to enhance the adhesion between the electrodes.

[0090] <In-line process S4>

[0091] The winding process S4 is a process of winding in the ends of each collector tab that is separated by slits. The winding process S4 can be performed in parallel with the electrode lamination process S3. That is, the winding of each collector tab can be performed while the negative electrode and the positive electrode are being laminated.

[0092] <Collider terminal bonding process S5>

[0093] The collector terminal bonding process S5 is a process of bonding the wound collector tabs to the collector terminals. There are no particular limitations on the bonding method; examples include laser welding, ultrasonic bonding, and soldering.

Claims

1. A battery comprising a power generation element and a current collection terminal, The power generation element comprises a plurality of collector tabs arranged in the thickness direction. The current collector terminal is coupled to the plurality of current collector tabs. At least one of the collector ears has at least one slit that divides the end of the collector ear in the width direction. The portions of the ends of the current collectors, separated by the slit, are electrically connected to the other current collectors adjacent to each other in the thickness direction. The electrical connection is formed by bending the portions of the two collector tabs together to form an electrical connection. A portion of the ends of the collector tabs that are separated by the slit are electrically connected to other collector tabs adjacent to each other on the upper side in the thickness direction, and another portion is electrically connected to other collector tabs adjacent to each other on the lower side in the thickness direction.

2. The battery according to claim 1, The portion of the end of the current collector ear that is divided by the slit is electrically connected to other current collector ears that are positioned at different locations in the thickness direction.

3. The battery according to claim 1 or 2, Each of the aforementioned collector ears has at least one of the aforementioned slits. The portions of the ends of the current collectors that are separated by the slit are electrically connected to the portions of the ends of the other current collectors that are adjacent in the thickness direction.

4. The battery according to claim 3, The portion of the end of the current collector ear and the portions of the ends of the other current collector ears are electrically connected by bending inward together to make contact.

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