battery

Abstract

The present invention provides a battery that effectively prevents damage to the electrode connector assembly. The battery (100) disclosed in the present invention satisfies D1>D2 when the length of the interval from the first end (21a) in the surface direction along the first sidewall (12b) to the positive electrode connector joint (22J) is D1, and the length of the interval from the second end (21b) in the same surface direction to the negative electrode connector joint (24J) is D2.

Description

[0001] This application is a divisional application of patent application No. 202211010308.5, filed on August 23, 2022, entitled "Battery". Technical Field

[0002] This invention relates to batteries. Background Technology

[0003] Lithium-ion rechargeable batteries and similar batteries generally include: an electrode body with electrodes, an outer packaging body with an opening that houses the electrode body, a sealing plate that seals the opening of the outer packaging body, and terminals that are electrically connected to the electrodes inside the outer packaging body and extend from the sealing plate to the outside of the outer packaging body. In such batteries, a known structure includes an electrode connector assembly with multiple current-collecting terminals on the electrodes, which is connected to the terminals via electrode current-collecting portions. For example, Patent Document 1 discloses a battery in which a positive electrode connector assembly is provided at one end along the length of the electrode body, and a negative electrode connector assembly is provided at the other end. Furthermore, the positive electrode connector assembly is connected to the positive current-collecting portion in a bent state, and the negative electrode connector assembly is connected to the negative current-collecting portion in a bent state.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: International Publication No. 2021 / 060010 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] However, in such batteries, connectors with different bending stiffness are mostly used as the positive and negative terminals. For example, a connector made of aluminum or an aluminum alloy can be used as the positive terminal, while a connector made of copper or a copper alloy can be used as the negative terminal. Furthermore, through research by the inventors, it was discovered that when the electrode body deviates from its designated position due to external force (e.g., an external force applied along the length of the electrode body), the bent portion (hereinafter referred to as the "bent portion") of the connector with higher bending stiffness is easily damaged. Therefore, there is a risk that the electrical connection between the electrode and the terminal will become unstable or poor, which is undesirable.

[0009] The present invention was made in view of the following circumstances, and its main objective is to provide a battery that effectively prevents damage to the electrode junction assembly (especially the positive electrode junction assembly).

[0010] Methods for solving problems

[0011] According to the present invention, a battery is provided comprising one or more electrode bodies including a positive electrode and a negative electrode, and a battery casing housing the electrode bodies. The battery casing is provided with an outer packaging body and a sealing plate. The outer packaging body has a bottom wall, a pair of first side walls extending from the bottom wall and opposing each other, a pair of second side walls extending from the bottom wall and opposing each other, and an opening opposite the bottom wall. The sealing plate seals the opening, and a positive terminal and a negative terminal are mounted on the sealing plate. The electrode body is provided with: a first end portion existing along the surface direction of the first side wall; a positive electrode connector assembly consisting of a plurality of positive electrode connectors protruding from the first end portion, each connector being made of aluminum or an aluminum alloy; a second end portion existing along the surface direction of the first side wall, different from the first end portion; and a negative electrode connector assembly consisting of a plurality of negative electrode connectors protruding from the second end portion, each connector being made of copper or a copper alloy. The thickness of each positive electrode connector constituting the positive electrode connector assembly is greater than the thickness of each negative electrode connector constituting the negative electrode connector assembly. The aforementioned positive terminal assembly and the aforementioned positive terminal are electrically connected via a positive current collector, which is equipped with a positive terminal joint. At the positive terminal joint, the front end portion of the aforementioned positive terminal assembly is joined in a bent configuration along the aforementioned second sidewall. The aforementioned negative terminal assembly and the aforementioned negative terminal are electrically connected via a negative current collector, which is equipped with a negative terminal joint. At the negative terminal joint, the front end portion of the aforementioned negative terminal assembly is joined in a bent configuration along the aforementioned second sidewall. When the length of the distance from the first end to the positive terminal joint in the planar direction is D1, and the length of the distance from the second end to the negative terminal joint in the planar direction is D2, D1>D2 is satisfied. Details will be described later. As described above, by ensuring D1>D2, for example, even if the electrode body deviates from its predetermined configuration position due to an external force applied in the longitudinal direction of the electrode body, damage to the electrode terminal assembly (especially the positive terminal assembly) can be effectively prevented.

[0012] In a preferred embodiment of the battery disclosed herein, the positive electrode connector assembly is joined to the electrode body side surface of the positive electrode current collector, and the negative electrode connector assembly is joined to the electrode body side surface of the negative electrode current collector. When configured in this way, contact between the edge of the electrode current collector and the electrode connector assembly can be effectively suppressed, thus better preventing damage to the electrode connector assembly.

[0013] In one embodiment of the battery disclosed herein, the number of positive terminals constituting the aforementioned positive terminal group is less than the number of negative terminals constituting the aforementioned negative terminal group.

[0014] In one embodiment of the battery disclosed herein, the positive electrode is equipped with an elongated positive current collector and positive terminals formed at multiple locations along the elongated direction of the positive current collector. A positive active material layer is formed on the positive current collector, and a positive protective layer is formed at the ends of the positive active material layer and on the positive terminals. Similarly, the negative electrode is equipped with an elongated negative current collector and negative terminals formed at multiple locations along the elongated direction of the negative current collector. A negative active material layer is formed on both the negative current collector and the negative terminals.

[0015] In one type of battery, the length of the portion of the positive electrode protective layer formed in the protruding direction of the positive electrode connector is smaller than the length of the portion of the negative electrode active material layer formed in the protruding direction of the negative electrode connector.

[0016] In a preferred embodiment of the battery disclosed herein, the electrode body is equipped with a pair of flat outer surfaces, and a fixing member is disposed from at least one of the flat outer surfaces to the positive or negative current collector. When configured in this way, for example, it can effectively prevent the electrode body from deviating from its predetermined position due to the application of an external force along its length. Therefore, it is preferred because it can better prevent damage to the electrode connector assembly.

[0017] In a preferred embodiment of the battery disclosed herein, an insulating member is further provided to insulate the sealing plate from the positive or negative current collector. The insulating member has a base and one or more protrusions. The base is disposed between the sealing plate and the positive or negative current collector, and the protrusions are located on the central side of the electrode body in a direction closer to the surface than the base, protruding from the sealing plate side towards the electrode body side. With this configuration, for example, it is possible to effectively prevent the electrode body from deviating from its predetermined position due to an external force applied in a direction perpendicular to the length direction of the electrode body. Therefore, it is preferred because it better prevents damage to the electrode connector assembly. Attached Figure Description

[0018] Figure 1 This is a schematic perspective view of a battery according to one embodiment.

[0019] Figure 2 It is along Figure 1 A schematic longitudinal section view of line II-II.

[0020] Figure 3 yes Figure 2 Enlarged view of the positive terminal assembly and the area near the negative terminal assembly.

[0021] Figure 4 It is along Figure 1 A schematic longitudinal section view of line IV-IV.

[0022] Figure 5 It is along Figure 1 A schematic cross-sectional view of the VV line.

[0023] Figure 6 yes Figure 5 Enlarged view of the positive terminal assembly and the area near the negative terminal assembly.

[0024] Figure 7 yes Figure 5 Enlarged view of the area near the positive terminal connector group.

[0025] Figure 8 This is a schematic three-dimensional view of the electrode assembly installed on the sealing plate.

[0026] Figure 9 It is a three-dimensional view schematically showing the electrode body with the positive second collector and the negative second collector installed.

[0027] Figure 10 This is a schematic diagram showing the structure of a wound electrode body according to one embodiment.

[0028] Figure 11 It is a schematic representation Figure 2 An enlarged cross-sectional view of the area near the positive end.

[0029] Figure 12 It is a perspective view schematically showing a sealing plate with a positive terminal, a negative terminal, a first positive current collector, a first negative current collector, a positive insulating component, and a negative insulating component installed.

[0030] Figure 13 It is Figure 12 A three-dimensional view of the sealing plate turned upside down.

[0031] Figure 14 This is a schematic cross-sectional view illustrating the battery insertion process according to one embodiment.

[0032] Figure 15 This is an explanatory diagram illustrating a battery according to other embodiments. Detailed Implementation

[0033] Hereinafter, with reference to the accompanying drawings, several preferred embodiments of the technology disclosed herein will be described. Furthermore, for matters not specifically mentioned in this specification but necessary for the implementation of the invention (e.g., the general structure and manufacturing process of a non-characteristic battery without the invention), these can be understood as design matters by those skilled in the art based on existing technology. The invention can be implemented based on the disclosures in this specification and common technical knowledge in the art. The following description is not intended to limit the technology disclosed herein to the following embodiments. Additionally, in this specification, the expression "A to B" indicating a numerical range includes not only meaning above A and below B, but also meaning "greater than A" and "less than B".

[0034] Furthermore, in this specification, the term "battery" refers to all energy storage devices capable of extracting electrical energy, encompassing both primary and secondary batteries. Additionally, the term "secondary battery" refers to all energy storage devices capable of repeated charging and discharging, including so-called storage batteries (chemical batteries) such as lithium-ion batteries or nickel-metal hydride batteries, as well as capacitors (physical batteries) such as double-layer capacitors. Furthermore, in this specification, "bending stiffness" is a concept determined by the longitudinal elastic modulus (Young's modulus) and the cross-sectional shape.

[0035] <Battery 100>

[0036] Figure 1 It is a 3D image of battery 100. Figure 2 It is along Figure 1 A schematic longitudinal section view of line II-II. Figure 4 It is along Figure 1 A schematic longitudinal section view of line IV-IV. Figure 5 It is along Figure 1 A schematic cross-sectional view of the VV line. Furthermore, in the following description, the symbols L, R, F, Rr, U, D, etc., in the attached drawings represent left, right, front, back, top, and bottom, respectively; the symbols X, Y, Z represent the short side direction of the battery 100, the long side direction orthogonal to the short side direction (also called the length direction of the electrode body), and the up-down direction, respectively. However, these are merely directions for ease of explanation and do not impose any limitations on the arrangement of the battery 100.

[0037] like Figure 2As shown, the battery 100 is equipped with a battery case 10, an electrode body group 20, a positive terminal 30, a negative terminal 40, a positive current collector 50, a negative current collector 60, a positive insulating member 70, and a negative insulating member 80. Additionally, the electrode bodies 20a, 20b, 20c that make up the electrode body group 20 are respectively equipped with a positive connector group 23 and a negative connector group 25. In the battery 100 according to the present embodiment, the positive connector 22t (refer to Figure 5 ) that makes up the positive connector group 23 is made of aluminum, the negative connector 24t (refer to Figure 5 ) that makes up the negative connector group 25 is made of copper, and the thickness of the positive connector group 23 is greater than the thickness of the negative connector group 25. A structure is formed in which the bending rigidity of the positive connector group 23 is higher than the rigidity of the negative connector group 25. Additionally, although not shown in the figure, here, the battery 100 is also equipped with an electrolyte. Here, the battery 100 is a lithium-ion secondary battery.

[0038] As Figure 3 shown, the battery 100 according to the present embodiment is characterized in that when the length (the shortest distance) of the interval from the first end 21a existing in the plane direction along the first side wall 12b (i.e., Figure 3 the long side direction Y) to the positive connector joint 22J at the positive second current collector 52 is D1, and the length (the shortest distance) of the interval from the second end 21b to the negative connector joint 24J at the negative second current collector 62 in the above-mentioned plane direction is D2, D1 > D2 is satisfied. Thus, by making D1 > D2, compared with a battery where D1 = D2 or D1 < D2, the load applied to the positive connector group 23 can be reduced well. As a result, since damage to the electrode connector group (especially the positive connector group 23) can be prevented well, it is preferable.

[0039] Here, the ratio of D1 to D2 (D1 / D2) is not particularly limited as long as it achieves the technical effects disclosed herein, but it can be approximately 1.1 or higher. From the viewpoint of better reducing the load applied to the positive terminal assembly 23, it is preferable to be 1.2 or higher, more preferably 1.5 or higher, and even more preferably 2 or higher. Furthermore, the upper limit of the above ratio (D1 / D2) is not particularly limited as long as it achieves the technical effects disclosed herein, but it can be approximately 10 or lower. From the viewpoint of making the load applied to the negative terminal assembly more appropriate, it is preferable to be 5 or lower, more preferably 4 or lower (e.g., 3 or lower). Furthermore, the sizes of D1 and D2 are not particularly limited as long as they achieve the technical effects disclosed herein. For example, the size of D2 is approximately 0.5 mm or higher, for example, it can be 1 mm or higher. The upper limit of the size of D2 is not particularly limited as long as it achieves the technical effects disclosed herein, but it can be approximately 5 mm or lower, for example, 4 mm or lower, 3 mm or lower, or 2 mm or lower. That is, the size of D2 can be 1mm to 2mm. In addition, the size of D1 can be appropriately determined by referring to the size of D2, the above ratio (D1 / D2), etc.

[0040] Figure 6 yes Figure 5 Enlarged view of the positive terminal assembly and the area near the negative terminal assembly. Figure 6 In this designation, the bent portion of the positive electrode connector 22t constituting the positive electrode connector assembly 23 is designated as 22W, and the bent portion of the negative electrode connector 24t constituting the negative electrode connector assembly 25 is designated as 24W. Here, the bent portion 22W can be considered as the portion of the positive electrode connector 22t from the first end 21a to the positive electrode connector joint 22J, and the bent portion 24W can be considered as the portion of the negative electrode connector 24t from the second end 21b to the negative electrode connector joint 24J. Furthermore, the bent portion of the innermost positive electrode connector 22t' in the positive electrode connector 22t constituting the positive electrode connector assembly 23 is designated as 22W', and the bent portion of the innermost negative electrode connector 24t' in the negative electrode connector 24t constituting the negative electrode connector assembly 25 is designated as 24W'. Additionally, the arcuate portion of the bent portion 22W' is designated as 22R, and the arcuate portion of the bent portion 24W' is designated as 24R.

[0041] Here, when the minimum bending radius in the arc-shaped portion 22R is 22r (not shown in the figure) and the minimum bending radius in the arc-shaped portion 24R is 24r (not shown in the figure), the ratio of the minimum bending radius 22r to the minimum bending radius 24r (22r / 24r) is not particularly limited as long as the technical effect disclosed herein is achieved, but it can be approximately 1.1 or higher. Furthermore, from the viewpoint that D1>D2, thereby effectively preventing damage to the positive electrode connector assembly 23, the above ratio (22r / 24r) is preferably 1.5 or higher, more preferably 1.8 or higher, and even more preferably 2 or higher. Furthermore, the upper limit of the above ratio (22r / 24r) is not particularly limited as long as the technical effect disclosed herein is achieved, but it can be approximately 4 or lower. From the viewpoint of making the load applied to the negative electrode connector assembly more suitable, it is preferably 3 or lower, more preferably 2.5 or lower. Additionally, the minimum bending radii 22r and 24r can be measured, for example, by an image measuring instrument. For example, the ratio (22r / 24r) can be changed by adjusting the lengths of D1 and D2.

[0042] Figure 7 yes Figure 5 Enlarged view of the area near the positive terminal connector group. Figure 7 In the diagram, D1' represents a length equivalent to 1 / 3 of D1. Furthermore, T1 represents the thickness of the positive electrode connector assembly 23, and T1' represents the thickness of the positive electrode connector assembly 23 at the position of D1'. Here, the thickness of the positive electrode connector assembly 23 can be (the thickness of the positive electrode connector 22t) × (the number of positive electrode connectors 22t). Additionally, for example, if there are gaps between the positive electrode connectors, the thickness of the positive electrode connector assembly can include the thickness of these gaps. Since the possibility of the positive electrode connector contacting the end of the negative electrode by passing over adjacent spacers is reduced when there are gaps between the positive electrode connectors, this is preferable.

[0043] Here, the ratio of T1' to T (T1' / T1) is not particularly limited as long as the technical effects disclosed herein are achieved, but it can be approximately 0.5 or higher. From the viewpoint of preventing plastic deformation caused by bending the positive terminal 22t, it is preferable to be 0.6 or higher, more preferably 0.7 or higher, and even more preferably 0.8 or higher. Furthermore, there is no particular limit to the upper limit of the above ratio (T1' / T1), but it can be approximately 0.9 or lower.

[0044] like Figure 2As shown, the battery casing 10 is a frame that houses the electrode assembly 20. Here, the battery casing 10 has a flat, bottomed cuboid shape (square). The material of the battery casing 10 can be the same as that used in the past, without particular limitation. The battery casing 10 is preferably made of metal, for example, more preferably aluminum, aluminum alloy, iron, iron alloy, etc. Figure 2 As shown, the battery casing 10 is equipped with an outer packaging body 12 having an opening 12h and a sealing plate (cover) 14 that blocks the opening 12h.

[0045] like Figure 1 As shown, the outer packaging 12 is equipped with a bottom wall 12a, a pair of long sidewalls 12b extending from the bottom wall 12a and opposite to each other, and a pair of short sidewalls 12c extending from the bottom wall 12a and opposite to each other. The bottom wall 12a is generally rectangular in shape. The bottom wall 12a is opposite to the opening 12h. The area of ​​the short sidewalls 12c is smaller than the area of ​​the long sidewalls 12b. The long sidewalls 12b and the short sidewalls 12c are examples of the first and second sidewalls disclosed herein. A sealing plate 14 is installed on the outer packaging 12 to block the opening 12h of the outer packaging 12. The sealing plate 14 is opposite to the bottom wall 12a of the outer packaging 12. The sealing plate 14 is generally rectangular in shape when viewed from above. The battery housing 10 is integrated by joining (e.g., welding) the sealing plate 14 to the periphery of the opening 12h of the outer packaging 12. The battery housing 10 is hermetically sealed (closed).

[0046] like Figure 2 As shown, the sealing plate 14 is provided with an injection hole 15, a gas vent valve 17, and two terminal outlet holes 18 and 19. The injection hole 15 is for injecting electrolyte after the sealing plate 14 is assembled into the outer packaging body 12. The injection hole 15 is sealed by the sealing member 16. The gas vent valve 17 is configured to rupture when the pressure inside the battery housing 10 reaches a specified value, thereby venting the gas inside the battery housing 10 to the outside. The terminal outlet holes 18 and 19 are formed at both ends of the sealing plate 14 in the long side direction Y. The terminal outlet holes 18 and 19 penetrate the sealing plate 14 in the vertical direction Z. The terminal outlet holes 18 and 19 have an inner diameter that allows the positive terminal 30 and the negative terminal 40 to be inserted through before installation onto the sealing plate 14 (before riveting).

[0047] The positive terminal 30 and the negative terminal 40 are respectively fixed to the sealing plate 14. The positive terminal 30 is located on one side of the long side Y direction of the sealing plate 14. Figure 1 , Figure 2 (Left side). The negative terminal 40 is positioned on the other side of the long side Y direction of the sealing plate 14 ( Figure 1 , Figure 2 (The right side). For example, Figure 1As shown, the positive terminal 30 and the negative terminal 40 are exposed on the outer surface of the sealing plate 14. Figure 2 As shown, the positive terminal 30 and the negative terminal 40 pass through the terminal lead-out holes 18 and 19 and extend outward from the inside of the sealing plate 14. Here, the positive terminal 30 and the negative terminal 40 are riveted to the periphery of the sealing plate 14 surrounding the terminal lead-out holes 18 and 19 by riveting. At the ends of the positive terminal 30 and the negative terminal 40 on the outer packaging body 12 side ( Figure 2 The lower end of the part forms a riveting part 30c, 40c.

[0048] like Figure 2 As shown, the positive terminal 30 is electrically connected to the positive terminal 22 of the electrode assembly 20 via the positive current collector 50 inside the outer packaging 12. The negative terminal 40 is electrically connected to the negative terminal 24 of the electrode assembly 20 via the negative current collector 60 inside the outer packaging 12. The positive terminal 30 is insulated from the sealing plate 14 by means of the positive insulating member 70 and the washer 90. The negative terminal 40 is insulated from the sealing plate 14 by means of the negative insulating member 80 and the washer 90. The positive terminal 30 and the negative terminal 40 are examples of the terminals disclosed herein.

[0049] The positive terminal 30 is preferably made of metal, for example, more preferably aluminum or an aluminum alloy. The negative terminal 40 is preferably made of metal, for example, more preferably copper or a copper alloy. The negative terminal 40 may also be constructed by joining and integrating two conductive members. For example, the portion connected to the negative current collector 60 may be made of copper or a copper alloy, while the portion exposed on the outer surface of the sealing plate 14 may be made of aluminum or an aluminum alloy.

[0050] like Figure 1 As shown, a plate-shaped positive electrode external conductive member 32 and a negative electrode external conductive member 42 are mounted on the outer surface of the sealing plate 14. The positive electrode external conductive member 32 is electrically connected to the positive terminal 30. The negative electrode external conductive member 42 is electrically connected to the negative terminal 40. The positive electrode external conductive member 32 and the negative electrode external conductive member 42 are components that provide a busbar when multiple batteries 100 are electrically connected to each other. The positive electrode external conductive member 32 and the negative electrode external conductive member 42 are preferably made of metal, for example, more preferably aluminum or an aluminum alloy. The positive electrode external conductive member 32 and the negative electrode external conductive member 42 are insulated from the sealing plate 14 by means of an external insulating member 92. However, the positive electrode external conductive member 32 and the negative electrode external conductive member 42 are not essential and may be omitted in other embodiments.

[0051] Figure 8This is a schematic perspective view of the electrode assembly 20 mounted on the sealing plate 14. Here, the electrode assembly 20 has three electrodes 20a, 20b, and 20c. However, there is no particular limitation on the number of electrodes disposed inside an outer packaging body 12; it can be two or more, or it can be one. Here, the electrode assembly 20 is held in place by an electrode holder 29 made of resin sheet (see reference 1). Figure 4 The state configuration covered is located inside the outer packaging 12.

[0052] Figure 9 This is a schematic three-dimensional view of electrode body 20a. Figure 10 This is a schematic diagram illustrating the structure of electrode 20a. Furthermore, the following explanation uses electrode 20a as an example; however, the same structure can also be used for electrodes 20b and 20c. Figure 10 As shown, the electrode body 20a has a positive electrode 22 and a negative electrode 24. Here, the electrode body 20a is a flat wound electrode body formed by stacking the strip-shaped positive electrode 22 and the strip-shaped negative electrode 24 with the strip-shaped spacer 26 in between and winding them around the winding shaft WL.

[0053] Electrode body 20a is disposed inside the outer packaging body 12 with its winding axis WL parallel to the long side direction Y. In other words, electrode body 20a is disposed inside the outer packaging body 12 with its winding axis WL parallel to the bottom wall 12a and orthogonal to the short side wall 12c. The end face of electrode body 20a (in other words, the laminated surface of the positive electrode 22 and the negative electrode 24) Figure 10 The end face of the long side in the Y direction is opposite to the short sidewall 12c.

[0054] like Figure 4 As shown, the electrode body 20a has a pair of curved portions 20r opposite to the bottom wall 12a of the outer packaging body 12 and the sealing plate 14, and a flat portion 20f connecting the pair of curved portions 20r and opposite to the long side wall 12b of the outer packaging body 12. However, the electrode body 20a may also be a stacked electrode body formed by stacking multiple square (typically rectangular) positive electrodes and multiple square (typically rectangular) negative electrodes in an insulated state.

[0055] like Figure 10 As shown, the positive electrode 22 has a positive current collector 22c, and a positive active material layer 22a and a positive protective layer 22p fixed to at least one surface of the positive current collector 22c. However, the positive protective layer 22p is not necessary and can be omitted in other embodiments. The positive current collector 22c is strip-shaped. The positive current collector 22c is made of conductive metals such as aluminum, aluminum alloy, nickel, and stainless steel. Here, the positive current collector 22c is a metal foil, specifically an aluminum foil.

[0056] At one end of the positive current collector 22c along the long side direction Y ( Figure 10 The first end 21a) is provided with multiple positive terminals 22t. The multiple positive terminals 22t are respectively positioned towards one side of the long side direction Y ( Figure 10 The first end 21a) protrudes. Multiple positive electrode connectors 22t protrude in the long side direction Y from the spacer 26. The multiple positive electrode connectors 22t are spaced apart (intermittently) along the length of the positive electrode 22. Each of the multiple positive electrode connectors 22t is trapezoidal in shape. The positive electrode connectors in the technology disclosed herein are made of aluminum (Al) or an aluminum alloy. Furthermore, "aluminum" in this specification and claims may also refer to materials containing unavoidable components other than aluminum. Additionally, "aluminum alloy" may be an alloy primarily composed of aluminum; for example, it may be an alloy containing 70% or more, 80% or more, or 90% or more (e.g., 95% or more) aluminum when the total mass of the aluminum alloy is 100% by mass, but it is not limited to this. Here, the positive electrode connector 22t is formed as part of the positive current collector 22c made of aluminum; however, the positive electrode connector may also be a separate component independent of the positive current collector. The positive terminal connector 22t is the portion of the positive current collector 22c where the positive active material layer 22a and the positive protective layer 22p are not formed (the exposed portion of the current collector). Alternatively, the positive terminal connector 22t can also be located at the end on the opposite side of the long side direction Y. Figure 10 (the right end).

[0057] like Figure 5 As shown, multiple positive terminals 22t are located at one end of the terminal in the Y direction (long side direction). Figure 5 The positive electrode connectors 21a) are stacked at the first end to form a positive electrode connector group 23. Multiple positive electrode connectors 22t are bent and folded with their outer ends aligned. The positive electrode connector group 23 is electrically connected to the positive terminal 30 via the positive electrode current collector 50. In this embodiment, the positive electrode connector group 23 is attached to the surface of the electrode body 20a side at the positive electrode second current collector 52. While the technology disclosed herein can also be applied in the case where the positive electrode connector group is attached to the surface of the second sidewall side at the positive electrode second current collector, in the former case, since contact between the edge of the positive electrode second current collector 52 and the positive electrode connector group 23 can be well suppressed, damage to the electrode connector group can be better prevented. Furthermore, as... Figure 5 As shown, the positive electrode second current collector 52 is equipped with a positive electrode connector joint 22J. At the positive electrode connector joint 22J, the front end portion 22S of the positive electrode connector assembly 23 is joined in a bent configuration along the second sidewall 12c. For the dimensions of the plurality of positive electrode connectors 22t (length in the long side direction Y and width orthogonal to the long side direction Y), refer to... Figure 10The connection to the positive current collector 50 can be appropriately adjusted, for example, by means of its formation position. While not limited thereto, the thickness of the positive electrode connector 22t can be, for example, between 5 μm and 30 μm (preferably between 10 μm and 20 μm). Here, the plurality of positive electrode connectors 22t have different dimensions from each other so that the outer ends align when bent. The positive electrode connector group 23 is an example of the electrode connector group disclosed herein.

[0058] like Figure 10 As shown, the positive electrode active material layer 22a is arranged in a strip shape along the length direction of the strip-shaped positive electrode current collector 22c. The positive electrode active material layer 22a includes a positive electrode active material (e.g., a lithium transition metal composite oxide such as a lithium nickel cobalt manganese composite oxide) capable of reversibly attracting and releasing charge carriers. When the total solid content of the positive electrode active material layer 22a is 100% by mass, the positive electrode active material can account for approximately 80% by mass or more, typically 90% by mass or more, for example, 95% by mass or more. The positive electrode active material layer 22a may also contain any components other than the positive electrode active material, such as conductive materials, binders, various additives, etc. As a conductive material, for example, carbon materials such as acetylene black (AB) can be used. As a binder, for example, polyvinylidene fluoride (PVdF) can be used. Although not limited to these, the thickness of the positive electrode active material layer 22a can be, for example, 100 μm to 200 μm (preferably, 120 μm to 150 μm).

[0059] like Figure 10 As shown, the positive electrode protective layer 22p is disposed in the longitudinal direction Y at the interface between the positive electrode current collector 22c and the positive electrode active material layer 22a. Here, the positive electrode protective layer 22p is disposed at one end of the positive electrode current collector 22c in the longitudinal direction Y ( Figure 10 (The left end). However, the positive electrode protective layer 22p can also be provided at both ends in the long side direction Y. The positive electrode protective layer 22p is provided in a strip shape along the positive electrode active material layer 22a. The positive electrode protective layer 22p contains an inorganic filler (e.g., alumina). When the total solid content of the positive electrode protective layer 22p is 100% by mass, the inorganic filler can account for approximately 50% by mass or more, typically 70% by mass or more, for example, 80% by mass or more. The positive electrode protective layer 22p can also contain any component other than the inorganic filler, such as conductive materials, binders, various additives, etc. The conductive materials and binders can also be the same as those exemplified materials that can be included in the positive electrode active material layer 22a. Although not limited to this, the thickness of the positive electrode protective layer 22p can, for example, be in the range of 30 μm to 150 μm (preferably, in the range of 50 μm to 100 μm).

[0060] like Figure 10As shown, in the battery 100 according to this embodiment, in addition to the positive current collector 22c, a positive electrode protective layer 22p is also formed on the positive electrode connector 22t. Here, for the protruding direction of the positive electrode connector 22t (i.e., Figure 10 The shortest length 22A of the positive electrode protective layer 22p formed on the left side can be appropriately adjusted, for example, by means of its formation position, taking into account the state of connection with the positive electrode current collector 50. Although not limited to this, the length 22A can be, for example, 1 mm to 10 mm (preferably 2 mm to 5 mm). In addition, there is no particular limitation on the ratio of the thickness of the positive electrode protective layer 22p to the thickness of the positive electrode active material layer 22a (thickness of the positive electrode protective layer / thickness of the positive electrode active material layer), as long as the technical effects disclosed herein are achieved, but it can be approximately 0.3 to 0.7 (preferably 0.4 to 0.6).

[0061] like Figure 10 As shown, the negative electrode 24 has a negative electrode current collector 24c and a negative electrode active material layer 24a fixed to at least one surface of the negative electrode current collector 24c. The negative electrode current collector 24c is strip-shaped. The negative electrode current collector 24c is made of conductive metals such as copper, copper alloy, nickel, and stainless steel. Here, the negative electrode current collector 24c is a metal foil, specifically a copper foil.

[0062] At one end of the negative current collector 24c along the long side direction Y ( Figure 10 The second end 21b is provided with multiple negative terminals 24t. The multiple negative terminals 24t are positioned towards the side in the long side direction Y ( Figure 10 The second end 21b) protrudes. Multiple negative terminals 24t protrude in the long side direction Y of the spacer 26. Multiple negative terminals 24t are spaced apart (intermittently) along the length of the negative electrode 24. Each of the multiple negative terminals 24t is trapezoidal in shape. The negative terminals in the technology disclosed herein are made of copper (Cu) or a copper alloy. Furthermore, "copper" in this specification and claims may also refer to materials containing unavoidable components other than copper. Additionally, "copper alloy" may be an alloy primarily composed of copper; for example, it may be an alloy containing 70% or more, 80% or more, or 90% or more (e.g., 95% or more) copper when the total mass of the copper alloy is 100% by mass, but it is not limited to this. Here, the negative terminal 24t is formed as part of the negative current collector 24c made of copper; however, the negative terminal may also be a separate component independent of the negative current collector. Here, the negative electrode connector 24t is the portion of the negative electrode current collector 24c where the negative electrode active material layer 24a is not formed (the exposed portion of the current collector). Alternatively, the negative electrode connector 24t can also be located at the end on the opposite side in the long Y direction. Figure 10(The left end).

[0063] like Figure 5 As shown, multiple negative terminals 24t are located at one end of the terminal in the Y direction (long side direction). Figure 10 The negative electrode connectors 24t are stacked at the second end 21b) to form a negative electrode connector assembly 25. Multiple negative electrode connectors 24t are bent and folded with their outer ends aligned. The negative electrode connector assembly 25 is electrically connected to the negative terminal 40 via the negative electrode current collector 60. In this embodiment, the negative electrode connector assembly 25 is joined to the surface of the electrode body 20a side at the negative electrode second current collector 62. While the technology disclosed herein can also be applied to a surface connection between the negative electrode connector assembly and the second sidewall side at the negative electrode second current collector, in the former case, since contact between the edge of the negative electrode second current collector 62 and the negative electrode connector assembly 25 can be effectively suppressed, damage to the electrode connector assembly can be better prevented. Furthermore, as... Figure 5 As shown, the negative electrode second current collector 62 is equipped with a negative electrode connector engagement portion 24J, in which the front end portion 24S of the negative electrode connector assembly 25 is engaged in a bent state arranged along the second sidewall 12c. Preferably, a plurality of negative electrode connectors 24t are bent and electrically connected to the negative terminal 40. The negative electrode second current collector 62, which will be described later, is attached to the negative electrode connector assembly 25. For the dimensions of the plurality of negative electrode connectors 24t (length in the long side direction Y and width orthogonal to the long side direction Y), refer to Figure 10 Considering the connection state with the negative electrode current collector 60, adjustments can be made appropriately, for example, by means of its formation position. While not limited to this, the thickness of the negative electrode connector 24t can, for example, be between 3 μm and 30 μm (preferably between 5 μm and 15 μm). Here, the dimensions of the plurality of negative electrode connectors 24t are different from each other so that the outer ends are aligned when bent. The negative electrode connector group 25 is an example of the electrode connector group disclosed herein.

[0064] The negative electrode active material layer 24a is arranged in a strip shape along the length direction of the strip-shaped negative electrode current collector 24c. The negative electrode active material layer 24a contains a negative electrode active material (e.g., a carbon material such as graphite) capable of reversibly adsorbing and releasing charge carriers. When the total solid content of the negative electrode active material layer 24a is 100% by mass, the negative electrode active material can, for example, account for approximately 80% by mass or more, typically 90% by mass or more, for example 95% by mass or more. The negative electrode active material layer 24a may also contain any components other than the negative electrode active material, such as binders, dispersants, various additives, etc. As a binder, for example, rubbers such as styrene-butadiene rubber (SBR) can be used. As a dispersant, for example, cellulose-based materials such as carboxymethyl cellulose (CMC) can be used. Although not limited to these, the thickness of the negative electrode active material layer 24a can, for example, be in the range of 100 μm to 200 μm (preferably, in the range of 160 μm to 190 μm).

[0065] like Figure 10 As shown, in the battery 100 according to this embodiment, in addition to the negative electrode current collector 24c, a negative electrode active material layer 24a is also formed on the negative electrode connector 24t. Here, for the protruding direction of the negative electrode connector 24t (i.e., Figure 10 The shortest length 24A of the negative electrode active material layer 24a formed on the right side of the negative electrode active material layer 24a can be appropriately adjusted, for example, by means of its formation position, taking into account the state of connection with the negative electrode current collector 60. Although not limited to this, the length 24A can be, for example, in the range of 1 mm to 10 mm (preferably, in the range of 2 mm to 5 mm).

[0066] Furthermore, regarding the ratio (24A / 22A) of the aforementioned length 24A, there are no particular limitations as long as the technical effects disclosed herein are achieved; it can be approximately 0.5 or more, preferably 1.1 or more (e.g., 1.2 or more). Additionally, regarding the upper limit of the aforementioned ratio (24A / 22A), there are no particular limitations as long as the technical effects disclosed herein are achieved; it can be approximately 2 or less, for example, 1.8 or less or 1.5 or less. Here, when manufacturing an orthogonal connector group and a negative connector group satisfying D1>D2, it is necessary to make the length protruding from the first end 21a of each positive connector constituting the positive connector group greater than the length protruding from the second end 21b of each negative connector constituting the negative connector group. Furthermore, for example, when 24A>22A is achieved as in this embodiment, it is easy to make the length protruding from the first end 21a of the positive connector 22t greater than the length protruding from the second end 21b of the negative connector 24t (see reference). Figure 10Therefore, it is easy to manufacture a battery 100 that satisfies D1>D2. Furthermore, in the case where 24A≤22A, it is sufficient to pre-make the length of the protruding direction of the plurality of positive terminals 22t greater than the length of the protruding direction of the plurality of negative terminals 24t.

[0067] Furthermore, in the battery 100 according to this embodiment, the number of positive electrode terminals 22t' constituting the positive electrode terminal group 23 is the same as the number of negative electrode terminals 24t' constituting the negative electrode terminal group 25, but this is not a limitation. The ratio of the number of positive electrode terminals constituting the positive electrode terminal group to the number of negative electrode terminals constituting the negative electrode terminal group (number of positive electrode terminals / number of negative electrode terminals) is not particularly limited as long as the technical effects disclosed herein are achieved, and can be approximately 0.5 or higher. Furthermore, from the viewpoint of better reducing the load applied to the positive electrode terminals, the ratio (number of positive electrode terminals / number of negative electrode terminals) is preferably 0.9 or higher, more preferably 0.95 or higher. The upper limit of the ratio (number of positive electrode terminals / number of negative electrode terminals) is not particularly limited as long as the technical effects disclosed herein are achieved, and can be approximately 2.0 or lower. From the viewpoint of better ensuring the strength of the electrode terminal group, it is preferably 1.1 or lower, more preferably 1 or lower. In addition, when the ratio (number of positive terminals / number of negative terminals) is less than 1 (i.e., the number of positive terminals constituting the positive terminal group is less than the number of negative terminals constituting the negative terminal group), the capacity degradation that occurs with the charging and discharging of the battery can be reduced.

[0068] In the battery 100 according to this embodiment, the ratio of the thickness of the positive electrode connector 22t' constituting the positive electrode connector group 23 to the thickness of the negative electrode connector 24t' constituting the negative electrode connector group 25 (thickness of the positive electrode connector / thickness of the negative electrode connector) is not particularly limited as long as the technical effects disclosed herein are achieved, and can be approximately 1.1 or more, preferably 1.2 or more, and more preferably 1.5 or more. The upper limit of the above ratio (thickness of the positive electrode connector / thickness of the negative electrode connector) is not particularly limited as long as the technical effects disclosed herein are achieved, and can be approximately 5 or less. Furthermore, from the viewpoint of ensuring the strength of the electrode connector group, the above ratio (thickness of the positive electrode connector / thickness of the negative electrode connector) is preferably 3 or less, and more preferably 2.5 or less.

[0069] The spacer 26 is a component that insulates the positive electrode active material layer 22a of the positive electrode 22 from the negative electrode active material layer 24a of the negative electrode 24. As the spacer 26, a porous resin sheet made of a polyolefin resin such as polyethylene (PE) or polypropylene (PP) is preferably preferred. Furthermore, a heat resistance layer (HRL) containing an inorganic filler may be provided on the surface of the spacer 26. Examples of inorganic fillers include alumina, borosilicate, aluminum hydroxide, and titanium dioxide.

[0070] The electrolyte can be the same as in the past, without any particular restrictions. For example, the electrolyte can be a non-aqueous electrolyte containing a non-aqueous solvent and a supporting salt. Non-aqueous solvents include carbonates such as ethylene carbonate, dimethyl carbonate, and methyl ethyl carbonate. Supporting salts include, for example, fluorinated lithium salts such as LiPF6. The electrolyte can also be in solid form (solid electrolyte) and integrated with the electrode assembly 20.

[0071] The positive current collector 50 forms a conductive path that electrically connects the positive terminal group 23, consisting of multiple positive terminals 22t, to the positive terminal 30. For example... Figure 2 As shown, the positive current collector 50 is equipped with a first positive current collector 51 and a second positive current collector 52. The first positive current collector 51 and the second positive current collector 52 may also be made of the same type of metal as the positive current collector 22c, such as conductive metals such as aluminum, aluminum alloy, nickel, and stainless steel.

[0072] Figure 11 It is a schematic representation Figure 2 Enlarged cross-sectional view of the portion near the positive end 30. Figure 12 This is a schematic three-dimensional view of the sealing plate 14. Figure 13 It is Figure 12 A three-dimensional view of the sealing plate turned upside down. Figure 13 This refers to the inner side of the outer packaging body 12 of the sealing plate 14. For example... Figures 11-13 As shown, the positive electrode first current collector 51 is mounted on the inner surface of the sealing plate 14. The positive electrode first current collector 51 is an example of a current collector disclosed herein. The positive electrode first current collector 51 has a first region 51a and a second region 51b. The positive electrode first current collector 51 can be constructed by bending a component, for example, using pressure processing, or by integrating multiple components together using welding. Here, the positive electrode first current collector 51 is fixed to the sealing plate 14 by riveting.

[0073] The first region 51a is located between the sealing plate 14 and the electrode assembly 20. The first region 51a extends along the long side direction Y. The first region 51a extends horizontally along the inner surface of the sealing plate 14. A positive electrode insulating member 70 is disposed between the sealing plate 14 and the first region 51a. The first region 51a is insulated from the sealing plate 14 by means of the positive electrode insulating member 70. Here, the first region 51a is electrically connected to the positive terminal 30 by riveting. In the first region 51a, a through hole 51h is formed at a position corresponding to the terminal lead-out hole 18 of the sealing plate 14, extending in the vertical direction Z. The second region 51b is located between the short sidewall 12c of the outer packaging body 12 and the electrode assembly 20. The second region 51b extends from one end of the first region 51a along the long side direction Y ( Figure 11 The second region 51b extends along the vertical direction Z from the left end of the outer packaging body 12 to the short sidewall 12c.

[0074] The positive electrode second current collector 52 extends along the short sidewall 12c of the outer packaging body 12. The positive electrode second current collector 52, as... Figure 9 As shown, the device includes a current collector connection portion 52a, an inclined portion 52b, and a connector joint portion 52c. The current collector connection portion 52a is the part that is electrically connected to the positive electrode first current collector portion 51. The current collector connection portion 52a extends along the vertical direction Z. The current collector connection portion 52a is arranged approximately perpendicular to the winding axis WL of the electrode bodies 20a, 20b, and 20c. A recess 52d is provided in the current collector connection portion 52a, which is thinner than the surrounding thickness. A through hole 52e is provided in the recess 52d, extending in the short side direction X. A joint portion is formed in the through hole 52e to engage with the positive electrode first current collector portion 51. The joint portion is, for example, a welded joint portion formed by welding such as ultrasonic welding, resistance welding, or laser welding. A fuse may also be provided in the positive electrode second current collector portion 52.

[0075] The connector joint 52c is attached to the positive terminal connector group 23 and is the part that is electrically connected to multiple positive terminal connectors 22t. For example... Figure 8 As shown, the connector joint 52c extends along the vertical direction Z. The connector joint 52c is arranged substantially perpendicular to the winding axis WL of the electrode bodies 20a, 20b, and 20c. The surface of the connector joint 52c that connects to the plurality of positive electrode connectors 22t is arranged substantially parallel to the short sidewall 12c of the outer packaging body 12. Figure 5As shown, a positive electrode connector joint 22J is formed at the connector joint 52c to engage with the positive electrode connector assembly 23. The positive electrode connector joint 22J is, for example, a welded joint formed by ultrasonic welding, resistance welding, laser welding, or other welding methods when multiple positive electrode connectors 22t are overlapping. The welded structure positions the multiple positive electrode connectors 22t towards the side of the short side in the X direction of the electrode bodies 20a, 20b, and 20c. This allows for better bending of the multiple positive electrode connectors 22t, resulting in a stable formation such as... Figure 5 The positive terminal assembly 23 is shown in a curved shape.

[0076] The inclined portion 52b is the part connecting the lower end of the current collector connection portion 52a and the upper end of the connector joint portion 52c. The inclined portion 52b is inclined relative to the current collector connection portion 52a and the connector joint portion 52c. The inclined portion 52b connects the current collector connection portion 52a and the connector joint portion 52c such that, in the long side direction Y, the current collector connection portion 52a is located closer to the center than the connector joint portion 52c. This allows for an increase in the housing space of the electrode assembly 20, thereby achieving a higher energy density in the battery 100. Preferably, the lower end of the inclined portion 52b (in other words, the end on the bottom wall 12a side of the outer packaging 12) is located below the lower end of the positive electrode connector assembly 23. This allows for better bending of the multiple positive electrode connectors 22t and stable formation. Figure 5 The positive terminal assembly 23 is shown in a curved shape.

[0077] The negative current collector 60 forms a conductive path that electrically connects the negative terminal assembly 25, consisting of multiple negative terminals 24t, to the negative terminal 40. For example... Figure 2 As shown, the negative current collector 60 is equipped with a first negative current collector 61 and a second negative current collector 62. The first negative current collector 61 is an example of the current collector disclosed herein. The first negative current collector 61 and the second negative current collector 62 can be made of the same type of metal as the negative current collector 24c, for example, they can be made of conductive metals such as copper, copper alloy, nickel, and stainless steel. The structure of the first negative current collector 61 and the second negative current collector 62 can be the same as that of the first positive current collector 51 and the second positive current collector 52 of the positive current collector 50.

[0078] The negative electrode first collector section 61, such as Figure 13 As shown, it has a first region 61a and a second region 61b. A negative electrode insulating member 80 is disposed between the sealing plate 14 and the first region 61a. The first region 61a is insulated from the sealing plate 14 by means of the negative electrode insulating member 80. In the first region 61a, a through hole 61h is formed at a position corresponding to the terminal lead-out hole 19 of the sealing plate 14, extending in the vertical direction Z. The negative electrode second current collector 62, as shown... Figure 9As shown, the device has a current collector plate connecting portion 62a, an inclined portion 62b, and a connector engagement portion 62c attached to the negative electrode connector group 25 and electrically connected to a plurality of negative electrode connectors 24t. The current collector plate connecting portion 62a has a recess 62d that connects to the connector engagement portion 62c. A through hole 62e extending in the short side direction X is provided in the recess 62d.

[0079] Next, the positive electrode insulating member 70 will be described. Although the following description uses the positive electrode insulating member 70 as an example, the negative electrode insulating member 80 can also have the same structure. The positive electrode insulating member 70 is a member that insulates the sealing plate 14 from the positive electrode first current collector 51. The positive electrode insulating member 70 has resistance to the electrolyte used and electrical insulation properties, and is made of a resin material that can be elastically deformed. For example, preferably, it is made of polyolefin resins such as polypropylene (PP), fluorinated resins such as tetrafluoroethylene perfluoroalkoxyethylene copolymer (PFA), or polyphenylene sulfide (PPS).

[0080] Positive electrode insulating component 70, such as Figure 13 As shown, it has a base 70a and multiple protrusions 70b. Figure 11 As shown, in the long side direction Y, multiple protrusions 70b are provided on the central side of the base bottom 70a near the sealing plate 14. Figure 13 (Right side). Here, the base 70a and the protrusion 70b are integrally formed. Here, the positive electrode insulating member 70 is an integrally molded article formed from the resin material described above. Therefore, compared with the case where the base 70a and the protrusion 70b are formed as separate members, the number of members used can be reduced, and cost reduction can be achieved. In addition, the positive electrode insulating member 70 can be prepared more simply. By adopting such a configuration, for example, it is possible to effectively prevent the electrode bodies 20a, 20b, and 20c from deviating from their predetermined configuration positions due to external forces applied in a direction perpendicular to the length direction of the electrode body. Therefore, it is preferred because damage to the electrode connector assembly can be better prevented. In addition, the number of protrusions 70b can be appropriately changed. In addition, the same configuration can also be used for the base 80a and the multiple protrusions 80b.

[0081] <Manufacturing Method of Battery 100>

[0082] The manufacturing method of battery 100 is characterized by employing electrode bodies 20a, 20b, and 20c that satisfy D1>D2 as described above. Other than this, the manufacturing process is the same as before. For battery 100, the following components can be prepared as described above: battery casing 10 (outer packaging 12 and sealing plate 14), electrode body assembly 20 (electrode bodies 20a, 20b, and 20c), electrolyte, positive terminal 30, negative terminal 40, positive current collector 50 (positive first current collector 51 and positive second current collector 52), negative current collector 60 (negative first current collector 61 and negative second current collector 62), positive insulating member 70, and negative insulating member 80. For example, it can be manufactured using a manufacturing method including a first mounting step, a second mounting step, an insertion step, and a sealing step. Furthermore, the manufacturing method disclosed herein may also include other steps at any stage.

[0083] In the first installation process, the following is made: Figure 12 , Figure 13 The first assembly shown. Specifically, firstly, the positive terminal 30, the positive first current collector 51, the positive insulating member 70, the negative terminal 40, the negative first current collector 61, and the negative insulating member 80 are installed on the sealing plate 14.

[0084] The positive terminal 30, the first positive current collector 51, and the positive insulating member 70 are, for example, fixed to the sealing plate 14 by riveting (riveting). Figure 11 As shown, a riveting process is performed by clamping the washer 90 between the outer surface of the sealing plate 14 and the positive terminal 30, and then clamping the positive electrode insulating member 70 between the inner surface of the sealing plate 14 and the positive electrode first current collector 51. Alternatively, the washer 90 can be made of the same material as the positive electrode insulating member 70. Specifically, before riveting, the positive terminal 30 is inserted sequentially from above the sealing plate 14 into the through hole 90h of the washer 90, the terminal lead-out hole 18 of the sealing plate 14, the through hole 70h of the positive electrode insulating member 70, and the through hole 51h of the positive electrode first current collector 51, so that it protrudes below the sealing plate 14. Furthermore, the portion of the positive terminal 30 that protrudes downwards from the sealing plate 14 is riveted to apply compressive force in the vertical Z direction. Thus, at the front end of the positive terminal 30 ( Figure 2 The lower end of the part forms a riveting part 30c.

[0085] Through this riveting process, the washer 90, sealing plate 14, positive electrode insulating member 70, and positive electrode first current collector 51 are integrally fixed to the sealing plate 14, and the terminal lead-out hole 18 is sealed. Additionally, the riveting part 30c can also be welded to the positive electrode first current collector 51. This further improves conductivity reliability.

[0086] The fixing of the negative terminal 40, the first negative current collector 61, and the negative insulating member 80 can be performed in the same manner as the positive terminal side. That is, before riveting, the negative terminal 40 is inserted sequentially from above the sealing plate 14 into the through hole of the washer, the terminal lead-out hole 19 of the sealing plate 14, the through hole of the negative insulating member 80, and the through hole of the first negative current collector 61, so that it protrudes below the sealing plate 14. Furthermore, the portion of the negative terminal 40 that protrudes downward from the sealing plate 14 is riveted to apply compressive force in the vertical direction Z. As a result, at the front end of the negative terminal 40 ( Figure 2 The lower end of the part forms a riveting part 40c.

[0087] Next, on the outer surface of the sealing plate 14, the positive electrode external conductive member 32 and the negative electrode external conductive member 42 are installed via the external insulating member 92. Furthermore, the material of the external insulating member 92 can be the same as that of the positive electrode insulating member 70. Additionally, the positive electrode external conductive member 32 and the negative electrode external conductive member 42 can be installed after the insertion process (for example, after sealing the injection hole 15).

[0088] In the second installation step, using the first assembly produced in the first installation step, a process is fabricated as follows: Figure 8 The second assembly shown is the electrode assembly 20, which is integrated with the sealing plate 14. Specifically, firstly, as shown... Figure 10 As shown, an electrode body 20a is prepared, wherein the length of the positive terminal 22t protruding from the first end 21a is greater than the length of the negative terminal 24t protruding from the second end 21b. Furthermore, as... Figure 9 As shown, three electrode bodies 20a are prepared, and each electrode body having a positive electrode second current collector 52 and a negative electrode second current collector 62 attached thereto is designated as electrode bodies 20a, 20b, and 20c, and arranged side by side in the short side direction X. At this time, electrode bodies 20a, 20b, and 20c are all arranged side by side such that the positive electrode second current collector 52 is positioned on one side in the long side direction Y. Figure 8 (on the left side), the negative electrode second collector 62 is arranged on the other side in the long side direction Y ( Figure 8 (on the right side).

[0089] Next, as Figure 5As shown, with the multiple positive electrode connectors 22t bent, the first positive electrode current collector 51 (specifically, the second region 51b) fixed to the sealing plate 14 is joined to the second positive electrode current collector 52 (specifically, the current collector plate connection portion 52a) of the electrode bodies 20a, 20b, and 20c. Similarly, with the multiple negative electrode connectors 24t bent, the first negative electrode current collector 61 fixed to the sealing plate 14 is joined to the second negative electrode current collector 62 of the electrode bodies 20a, 20b, and 20c. As a joining method, for example, ultrasonic welding, resistance welding, laser welding, etc., can be used. In particular, welding performed by irradiation with high-energy rays such as lasers is preferred. Through this welding process, joint portions are formed in the recesses 52d of the second positive electrode current collector 52 and the recesses 62d of the second negative electrode current collector 62.

[0090] In the insertion process, the second composite object, which was created in the second installation process, is housed in the internal space of the outer packaging 12. Figure 14 This is a schematic cross-sectional view illustrating the insertion process. Specifically, firstly, for example, an insulating resin sheet made of a resin material such as polyethylene (PE) is bent into a bag or box shape to prepare an electrode holder 29. Secondly, the electrode assembly 20 is housed in the electrode holder 29. Then, the electrode assembly 20, covered by the electrode holder 29, is inserted into the outer packaging 12. If the electrode assembly 20 is heavy, approximately 1 kg or more, for example 1.5 kg or more, and further 2-3 kg, then... Figure 14 As shown, the outer packaging body 12 is preferably configured such that the long sidewall 12b of the outer packaging body 12 intersects the direction of gravity (the outer packaging body 12 is placed horizontally), and the electrode body assembly 20 is inserted into the outer packaging body 12.

[0091] In the sealing process, the sealing plate 14 is joined to the edge of the opening 12h of the outer packaging body 12, sealing the opening 12h. The sealing process can be performed simultaneously with the insertion process or after the insertion process. In the sealing process, it is preferable to weld the outer packaging body 12 to the sealing plate 14. The welding of the outer packaging body 12 to the sealing plate 14 can be performed, for example, by laser welding. Afterward, electrolyte is injected through the injection hole 15, and the injection hole 15 is blocked by the sealing member 16, thereby sealing the battery 100. The battery 100 can be manufactured as described above.

[0092] The battery 100 can be used for various purposes, but it is particularly suitable as a power source (drive power source) for electric motors in moving bodies (typically passenger cars, trucks, etc.) where external forces such as vibration or impact are applied during use. There are no particular limitations on the type of vehicle; examples include plug-in hybrid electric vehicles (PHEVs), hybrid electric vehicles (HEVs), and battery electric vehicles (BEVs). The battery 100 can also be suitable as a battery pack in which multiple batteries 100 are arranged in a predetermined orientation and a load is applied from the orientation using a constraint mechanism.

[0093] The above description illustrates several embodiments of the present invention; however, these embodiments are merely examples. The present invention can also be implemented in various other ways. The present invention can be implemented based on the disclosure herein and common technical knowledge in the field. The technology described in the claims includes various modifications and alterations to the embodiments illustrated above. For example, a portion of the above embodiments can be transformed into other modifications, and other modifications can be added to the above embodiments. Furthermore, any technical feature not described as essential can be appropriately deleted.

[0094] For example, such as Figure 15 As shown, for electrode bodies 20a, 20b, and 20c that satisfy D1>D2, a fixing member A can also be configured. Figure 15 In this configuration, from one of the flat outer surfaces 27a of the electrode body 20a to the positive electrode second collector 52 and the other flat outer surface 27b, the fixing member A is arranged in the shape of the Japanese katakana character "コ". The same applies to the other electrode bodies 20b and 20c. Furthermore, Figure 15 Reference numerals 27c and 27d denote the flat outer surface of electrode body 20b, and reference numerals 27e and 27f denote the flat outer surface of electrode body 20c. When this configuration is adopted, for example, it can effectively prevent electrode bodies 20a, 20b, and 20c from deviating from their designated positions due to external forces applied along the length of the electrode bodies. Therefore, damage to the electrode connector assembly can be better prevented, and this configuration is preferred. Furthermore, such a fixing member, for example, can be manufactured using... Figure 9 After the complex shown is prepared, it is then properly configured.

[0095] As the fixing member A, for example, a fixing member having a base material and an adhesive layer formed on the base material is preferably used. Examples of the base material include polyethylene (PE), polypropylene (PP), polyester, nylon, polyvinyl chloride, Teflon (registered trademark; polytetrafluoroethylene), polyimide, Kapaton (registered trademark; polyimide film), p-phenylene ether, polyethylene naphthalate, etc. The thickness of the base material is not particularly limited as long as the technical effects disclosed herein are achieved; it can be approximately 5 μm to 100 μm, preferably 10 μm to 50 μm. Furthermore, examples of materials constituting the adhesive layer include polyacrylic adhesive materials, silane adhesive materials, rubber adhesive materials, etc. Preferably, the adhesive layer has adhesive properties at room temperature (typically around 20°C). The thickness of the adhesive layer is not particularly limited as long as the technical effects disclosed herein are achieved; it can be approximately 5 μm to 100 μm, preferably 5 μm to 20 μm.

[0096] Alternatively, the fixing member can be configured from one flat outer surface all the way to the second collector of the negative electrode and another flat outer surface, or this configuration can be combined with the configuration described above. Alternatively, the fixing member can be configured in an L-shape from one flat outer surface to either the second collector of the positive electrode or the second collector of the negative electrode.

[0097] Explanation of reference numerals in the attached figures

[0098] 10 Battery casing

[0099] 12 Outer Packaging

[0100] 14 Sealing board

[0101] 20 electrode assembly

[0102] Electrode bodies 20a, 20b, and 20c

[0103] 22t, 22t' positive terminal connector

[0104] 22R curved section

[0105] 22W, 22W' Bend

[0106] 22J Positive terminal connector joint

[0107] 23 Positive terminal assembly (electrode assembly)

[0108] 24t, 24t' negative terminal connector

[0109] 24R curved section

[0110] 24W, 24W' Bend

[0111] 24J Negative terminal connector joint

[0112] 25. Negative electrode connector assembly (electrode connector assembly)

[0113] 30 Positive terminal (terminal)

[0114] 40 Negative terminal (terminal)

[0115] 50 Positive current collector

[0116] 51 Positive electrode first current collector

[0117] 52 Positive electrode second current collector

[0118] 60 Negative current collector

[0119] 61 Negative electrode first collector section

[0120] 62 Negative electrode second collector section

[0121] 70 Positive electrode insulating component (insulating component)

[0122] 70a base

[0123] 70b Protrusion

[0124] 80 Negative electrode insulating component (insulating component)

[0125] 80a base

[0126] 80b protrusion

[0127] 100 batteries

Claims

1. A method for manufacturing a battery, the battery being equipped with one or more electrode bodies including a positive electrode and a negative electrode, and a battery casing housing the electrode bodies, wherein, The battery casing is equipped with: An outer packaging body having a bottom wall, a pair of first side walls extending from the bottom wall and opposite each other, a pair of second side walls extending from the bottom wall and opposite each other, and an opening opposite the bottom wall; as well as A sealing plate, which seals the opening. The sealing plate is equipped with a positive terminal and a negative terminal. The electrode body is equipped with: A first end portion is present along the surface direction of the first sidewall; a positive electrode connector assembly is composed of a plurality of positive electrode connectors protruding from the first end portion, each connector being made of aluminum or an aluminum alloy; A second end, different from the first end, exists along the surface direction of the first sidewall; and a negative electrode connector assembly, the negative electrode connector assembly consisting of a plurality of negative electrode connectors protruding from the second end, each connector being made of copper or a copper alloy. The thickness of each positive terminal in the positive terminal assembly is greater than the thickness of each negative terminal in the negative terminal assembly. The positive terminal assembly and the positive terminal are electrically connected via the positive current collector. The positive current collector is equipped with a positive terminal connector joint, wherein the front end portion of the positive terminal connector assembly is engaged in a bent configuration along the second sidewall. The negative terminal assembly and the negative terminal are electrically connected via the negative current collector. The negative electrode current collector is equipped with a negative electrode connector engagement portion, wherein the front end portion of the negative electrode connector assembly is engaged in a bent configuration along the second sidewall. When the length of the interval from the first end to the positive terminal joint in the planar direction is D1, and the length of the interval from the second end to the negative terminal joint in the planar direction is D2, D1>D2, wherein the battery manufacturing method includes: The assembly process involves assembling the insulating components between the electrode body and the sealing plate; and In the insertion process, after the assembly process, with the outer packaging body arranged laterally such that the opening is on the side, the electrode body is inserted into the outer packaging body in such a state that the insulating member abuts against the electrode body.

2. The method for manufacturing a battery as described in claim 1, wherein, The positive electrode connector assembly is joined to the surface of the electrode body side in the positive electrode current collector. The negative electrode connector assembly is joined to the surface of the electrode body in the negative electrode current collector.

3. The method for manufacturing a battery as described in claim 1 or 2, wherein, The number of positive terminals constituting the positive terminal group is less than the number of negative terminals constituting the negative terminal group.

4. The method for manufacturing a battery as described in claim 1 or 2, wherein, The positive electrode is equipped with an elongated positive current collector and positive terminals formed at multiple locations along the elongated direction of the positive current collector. A positive electrode active material layer is formed on the positive electrode current collector, and a positive electrode protective layer is formed along the ends of the positive electrode active material layer and on the positive electrode connector. The negative electrode is equipped with a long strip of negative electrode current collector and negative electrode connectors formed at multiple locations along the long strip direction of the negative electrode current collector. A layer of negative electrode active material is formed on the negative electrode current collector and the negative electrode terminal.

5. The method for manufacturing a battery as described in claim 4, wherein, The length of the positive electrode protective layer forming portion in the protruding direction of the positive electrode connector is smaller than the length of the negative electrode active material layer forming portion in the protruding direction of the negative electrode connector.

6. The method for manufacturing a battery as described in claim 1 or 2, wherein, The electrode body is equipped with a pair of flat outer surfaces, and a fixing member is disposed from at least one of the flat outer surfaces to the positive electrode current collector or the negative electrode current collector.

7. The method for manufacturing a battery as described in claim 1 or 2, wherein, It is also equipped with an insulating component that insulates the sealing plate from the positive electrode current collector or the negative electrode current collector. The insulating component is equipped with: The base, wherein the base is disposed between the sealing plate and the positive current collector or the negative current collector; and One or more protrusions are provided on the central side of the electrode body in the direction closer to the surface than the base, and protrude from the sealing plate side toward the electrode body side.

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