Battery and module

Abstract

A battery according to the present disclosure is provided with: a flat electrode body in which positive electrodes and negative electrodes are alternately stacked with separators interposed therebetween; an exterior member that accommodates the electrode body; a positive electrode tab that protrudes from the exterior material in a first direction orthogonal to the thickness direction of the electrode body and is electrically connected to the positive electrode; and a negative electrode tab that protrudes from the exterior material in the first direction or in a direction opposite to the first direction, and that is electrically connected to the negative electrode. The exterior has at least one laminate sheet. The electrode body has, at both edge portions in a second direction orthogonal to the thickness direction and the first direction, non-contact portions where the positive electrode and the negative electrode do not contact the separator. The exterior member has a welded portion that welds between the laminated sheets via at least a portion of the non-contact portions.

Description

Technical Field

[0001] The present disclosure relates to batteries and modules. Background Art

[0002] Lithium secondary batteries (hereinafter also referred to as “batteries”) using non-aqueous electrolytes are used in information and communication technologies (for example, computers, smartphones, etc.), vehicles, power storage, and the like.

[0003] The battery has an electrode body in which positive and negative electrodes are alternately stacked with a separator. Electrode tabs are formed in the electrode body. When the battery is charged or discharged, the electrode tabs through which the current passes generate a lot of heat. The separator is usually a porous film made of resin. Therefore, the portion of the separator adjacent to the electrode tab is prone to shrinkage. If the separator shrinks, the positive electrode and the negative electrode may come into contact and cause a short circuit.

[0004] U.S. Patent Application Publication No. 2018 / 0145376 discloses a battery assembly 900 that can suppress shrinkage of a portion of a separator adjacent to an electrode tab. The battery assembly 900 is disposed in a battery housing of a battery. Figure 6 and Figure 7 As shown, the battery assembly 900 has a plurality of electrode plates 910 (positive or negative), a separator 920, and an insulating reinforcement portion 930 for suppressing thermal shrinkage of the separator 920. The separator 920 is inserted between each of the plurality of electrode plates 910. Each of the plurality of electrode plates 910 is formed with an electrode tab 911. The separator 920 has a surplus peripheral portion that is larger than the periphery of the electrode plate 910. The insulating reinforcement portion 930 is formed at a portion of the surplus peripheral portion of the separator 920 that is adjacent to the electrode tab 911. The insulating reinforcement portion 930 has a width W. The insulating reinforcement portion 930 connects the periphery of the electrode plate 910 and the surplus peripheral portion of the separator 920 to each other.

[0005] However, the specification of U.S. Patent Application Publication No. 2018 / 0145376 does not disclose the relationship between the battery assembly 900 and the battery case. When the battery assembly 900 is simply housed in the battery case, it is possible that the two edges E920 (see FIG. 1 ) of the separator 920 may be Figure 6 ) shrinks and causes a short circuit. Summary of the invention

[0006] The present disclosure has been achieved in view of the above circumstances. An object of one embodiment of the present disclosure is to provide a battery and a module that suppress the occurrence of a short circuit. Technical means to solve problems

[0007] Means for solving the above-mentioned problems include the following embodiments.

[0008] <1> A battery according to a first aspect of the present disclosure includes: A flat electrode body in which positive and negative electrodes are alternately stacked with separators between them; an outer casing containing the electrode body; a positive electrode tab protruding from the exterior member in a first direction perpendicular to the thickness direction of the electrode body and electrically connected to the positive electrode; and a negative electrode tab, protruding from the exterior member in the first direction or in a direction opposite to the first direction and electrically connected to the negative electrode, The outer member has at least one laminated sheet, The electrode body has non-contact portions where the positive electrode and the negative electrode do not contact the separator at two edge portions in a second direction perpendicular to the thickness direction and the first direction, The exterior member has a welding portion where the laminate sheets are welded via at least a portion of the non-contact portion.

[0009] In the present disclosure, a “laminated sheet” refers to a sheet having at least a metal layer, a first resin layer laminated on one main surface of the metal layer, and a second resin layer laminated on the other main surface of the metal layer. In the present disclosure, when the exterior component has one laminate sheet, "between the laminate sheets" refers to the first and second portions of one laminate sheet. When the exterior component has multiple laminate sheets, "between the laminate sheets" refers to a portion of the first laminate sheet and a portion of the second laminate sheet.

[0010] In the first embodiment, the outer member has a welding portion that welds at least a portion of the laminated sheets through the non-contact portion. That is, the portion of the separator corresponding to the two edges of the second direction of the electrode body (hereinafter also referred to as "two edges") is clamped between the laminated sheets and fixed to the welding portion. Therefore, when the battery is abnormally heated, the two edges of the separator of the first embodiment are more difficult to shrink than when the two edges of the separator are not clamped between the laminated sheets. As a result, the occurrence of short circuit is suppressed in the battery of the first embodiment.

[0011] <2> A second aspect of the present disclosure is a battery according to the battery described in <1> above, The positive electrode comprises a plurality of positive electrode sheets, The negative electrode comprises a plurality of negative electrode sheets, The separator comprises a plurality of separators. The electrode body is composed of the positive electrode sheets and the negative electrode sheets alternately stacked in the thickness direction with the separators interposed therebetween. The non-contact portion extends along the first direction.

[0012] The battery of the second embodiment is a so-called stacked type battery.

[0013] <3> A third aspect of the present disclosure is a battery according to the battery described in <1> or <2> above, When observing the exterior component from the thickness direction, the ratio of the area of ​​the non-contact portion in the welded portion (hereinafter also referred to as "SR10A") to the area of ​​the welded portion (hereinafter also referred to as "SR20") (hereinafter also referred to as "ratio (SR10A / SR20)") is greater than 10%.

[0014] As a result, the two edges of the separator of the third type are more firmly fixed at the welding portion than when the ratio (SR10A / SR20) is less than 10%. Therefore, the two edges of the separator of the third type are less likely to shrink when the battery is abnormally heated. As a result, the occurrence of short circuit is further suppressed in the battery of the third type.

[0015] <4> A fourth aspect of the present disclosure is a battery according to any one of <1> to <3>, wherein The surface of the non-contact portion of the welded portion of the separator (hereinafter also referred to as the "first portion") is rougher than the surface of a portion of the separator other than the non-contact portion of the welded portion (hereinafter also referred to as the "second portion").

[0016] In the present disclosure, "surface roughness" means that the value of surface roughness is large. As surface roughness, the arithmetic mean roughness (Ra) measured according to JIS B 0601:2013 can be mentioned.

[0017] Thus, the contact area between the first part of the fourth embodiment and the welded part is larger than that in the case where the surface of the first part is not rougher than the surface of the second part. Thus, the two edges of the separator of the fourth embodiment are more firmly fixed to the welded part. As a result, in the battery of the fourth embodiment, the occurrence of short circuit is further suppressed.

[0018] <5> A fifth aspect of the present disclosure is a battery according to any one of <1> to <4>, wherein The thickness of the non-contact portion in the welded portion of the separator is thinner than the thickness of a portion of the separator other than the non-contact portion in the welded portion.

[0019] Thus, the contact area between the first portion of the fifth embodiment and the welded portion is larger than that in the case where the thickness of the first portion is not thicker than the thickness of the second portion. Thus, the two edges of the separator of the fifth embodiment are more firmly fixed to the welded portion. As a result, in the battery of the fifth embodiment, the occurrence of a short circuit is further suppressed.

[0020] <6> A module according to a sixth aspect of the present disclosure includes: A plurality of batteries described in any one of <1> to <5>; and A housing that accommodates the plurality of batteries.

[0021] Thus, in the module of the sixth aspect, occurrence of a short circuit is suppressed.

[0022] According to the present disclosure, a battery and a module are provided in which occurrence of a short circuit is suppressed. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Exemplary embodiments of the present invention will be described in detail based on the following drawings, in which: Figure 1 It is a front view of a battery according to an embodiment of the present disclosure. Figure 2 yes Figure 1 II-II line cross-sectional view of a battery. Figure 3 It is a perspective view of a module involved in an embodiment of the present disclosure. Figure 4 It is a plan view of a state where a case cover of the module according to the embodiment of the present disclosure is removed. Figure 5 It is a schematic diagram of a vehicle equipped with a module according to an embodiment of the present disclosure. Figure 6 This is a front view of a battery assembly disposed in a battery case of a conventional battery. Figure 7 This is a side view of a battery assembly disposed in a battery case of a conventional battery. DETAILED DESCRIPTION

[0024] Hereinafter, embodiments of the present disclosure will be described. These descriptions and examples are provided to illustrate the embodiments, and are not intended to limit the scope of the embodiments. In the present disclosure, a combination of two or more preferred embodiments is a more preferred embodiment. In the present disclosure, a numerical range expressed using “to” indicates a range including the numerical values ​​described before and after “to” as the lower limit and the upper limit. In the numerical ranges recorded in the present disclosure, the upper limit or lower limit of one numerical range can be replaced by the upper limit or lower limit of another numerical range recorded in the present disclosure. In the numerical ranges recorded in the present disclosure, the upper limit or lower limit of the numerical range can be replaced by the value shown in the embodiment.

[0025] Hereinafter, embodiments of the battery and the module of the present disclosure will be described with reference to the accompanying drawings. In the drawings, the same reference numerals are given to the same or corresponding parts, and the description thereof will not be repeated.

[0026] (1)Battery like Figure 1 As shown, the battery 1 according to the embodiment of the present disclosure includes a flat electrode body 10, an exterior member 20, a positive electrode tab 30, a negative electrode tab 40, and a non-aqueous electrolyte (not shown). The battery 1 is a rectangular parallelepiped object.

[0027] In the present embodiment, one side of the short side direction of the main surface of the battery 1 is defined as the positive direction of the X-axis, and the opposite side thereof is defined as the negative direction of the X-axis. The positive electrode tab 30 side of the long side direction of the main surface of the battery 1 is defined as the positive direction of the Y-axis, and the opposite side thereof is defined as the negative direction of the Y-axis. One side of the thickness direction of the battery 1 is defined as the positive direction of the Z-axis, and the opposite side thereof is defined as the negative direction of the Z-axis. The X-axis, Y-axis, and Z-axis are respectively orthogonal to each other. The Y-axis is an example of a first direction. The X-axis is an example of a second direction. The Z-axis is an example of a thickness direction of an electrode body. In addition, these directions do not limit the directions of the battery of the present disclosure when in use.

[0028] The outer casing 20 contains the electrode body 10 and the non-aqueous electrolyte. The outer casing 20 has two welded portions R20. The positive electrode tab 30 faces the positive direction of the Y axis and protrudes from the outer casing 20. The negative electrode tab 40 faces the negative direction of the Y axis and protrudes from the outer casing 20.

[0029] The length L1 of the battery 1 in the X-axis direction (see Figure 1 ) is, for example, 80 mm to 110 mm. The length L2 of the battery 1 in the Y-axis direction (see Figure 1 ) is, for example, 530 mm to 600 mm. The length L3 of the battery 1 in the Z-axis direction (see Figure 2 ) For example, 7.0mm to 9.0mm.

[0030] (1.1) Electrode body The electrode body 10 has a stacked structure. Figure 2 As shown, the electrode body 10 includes a plurality of positive electrode sheets 11, a plurality of negative electrode sheets 12, and a plurality of separators 13. The electrode body 10 is formed by alternately stacking the positive electrode sheets 11 and the negative electrode sheets 12 with the separators 13 interposed therebetween. The positive electrode sheets 11 are an example of a positive electrode. The negative electrode sheets 12 are an example of a negative electrode. The separators 13 are an example of a separator.

[0031] The number of each of the positive electrode sheet 11 , the negative electrode sheet 12 , and the separator 13 is not particularly limited, and is appropriately selected according to the purpose of the battery 1 .

[0032] like Figure 1As shown, the electrode body 10 has a pair of non-contact portions R10A and an electrode portion R10B. The pair of non-contact portions R10A are located at both ends of the electrode body 10 in the X-axis direction. The electrode portion R10B is located between the pair of non-contact portions R10A in the X-axis direction.

[0033] The electrode portion R10B is a portion for generating electricity. In the electrode portion R10B, the positive electrode sheets 11 and the negative electrode sheets 12 are alternately stacked with separators 13 interposed therebetween. In the present embodiment, the outermost layer of the electrode portion R10B is formed by the separators 13. The length L4 of the electrode portion R10B in the X-axis direction (see Figure 1 ) is, for example, 60 mm to 105 mm. The length L5 of the electrode portion R10B in the Y-axis direction (see Figure 1 ) For example, 500mm~520mm.

[0034] The non-contact portion R10A is a portion that does not generate electricity. The non-contact portion R10A is a portion of the electrode body 10 where the positive electrode sheet 11 and the negative electrode sheet 12 do not contact the separator 13. That is, the non-contact portion R10A is composed only of a plurality of separators 13. The non-contact portion R10A extends in the Y-axis direction. The length L6 of the non-contact portion R10A in the X-axis direction (refer to Figure 1 ) is, for example, 1 mm to 20 mm. The length of the non-contact portion R10A in the Y-axis direction is equal to the length L5 of the electrode portion R10B in the Y-axis direction (see Figure 1 )same.

[0035] (1.1.1) Positive electrode The positive electrode sheet 11 has a positive electrode current collector (such as aluminum foil) and a positive electrode active material layer supported by the positive electrode current collector. The positive electrode active material layer contains a positive electrode active material. The positive electrode active material releases lithium ions into the non-aqueous electrolyte or absorbs lithium ions from the non-aqueous electrolyte. The positive electrode active material can be any known positive electrode active material (such as LiNiO2, LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 The positive electrode active material layer may further contain a known conductive material (such as carbon black), trilithium phosphate, and a known binder (such as polyvinylidene fluoride).

[0036] (1.1.2) Negative electrode The negative electrode sheet 12 has a negative electrode collector (such as copper foil, etc.) and a negative electrode active material layer supported by the negative electrode collector. The negative electrode active material layer contains a negative electrode active material. The negative electrode active material absorbs and stores lithium ions as charge carriers from a non-aqueous electrolyte and releases them to the non-aqueous electrolyte during charging and discharging. The negative electrode active material can be any known negative electrode active material (artificial graphite, lithium alloy (such as LiXM, M is C, Si, Sn, Sb, Al, Mg, Ti, Bi, Ge, Pb or P, etc., X is a natural number), etc.). The negative electrode active material layer may also contain a known binder (such as styrene butadiene copolymer, etc.).

[0037] (1.1.3) Separator The separator 13 electrically insulates the positive electrode from the negative electrode and provides a path for lithium ions to move between the positive electrode active material layer and the negative electrode active material layer. A porous film or the like can be cited as the separator 13. For example, polyethylene, polypropylene, etc. can be cited as the material of the porous film. The separator 13 can be a single-layer structure or a multi-layer structure.

[0038] The surface of the non-contact portion R10A in the welding portion R20 of the separator 13 is rougher than the surface of the portion of the separator 13 that is different from the non-contact portion R10A in the welding portion R20 (i.e., the electrode portion R10B). The welding portion R20 is usually formed by hot pressing. During hot pressing, creep occurs in the non-contact portion R10A of the separator 13. "Creep" refers to the phenomenon that when an external force acts on an object, the strain increases over time relative to a certain stress. That is, the surface of the non-contact portion R10A of the separator 13 is extended compared to the surface before hot pressing (i.e., the same surface as the surface of the electrode portion R10B). Therefore, the surface of the non-contact portion R10A in the welding portion R20 of the separator 13 becomes rougher than the surface of the electrode portion R10B.

[0039] The thickness of the non-contact portion R10A in the welding portion R20 of the separator 13 is thinner than the thickness of the portion (i.e., the electrode portion R10B) of the separator 13 other than the non-contact portion R10A in the welding portion R20. The welding portion R20 is generally formed by hot pressing. Therefore, the thickness of the non-contact portion R10A in the welding portion R20 of the separator 13 becomes thinner than the thickness of the electrode portion R10B.

[0040] (1.2) External parts The exterior member 20 covers the electrode body 10 , and seals the electrode body 10 and the non-aqueous electrolyte together with the positive electrode tab 30 and the negative electrode tab 40 .

[0041] In this embodiment, the outer packaging member 20 has one laminate sheet 200. One laminate sheet 200 has two convex portions 210 (see Figure 2 ). The outer packaging member 20 is obtained by bending one laminate sheet 200 and sandwiching and sealing the electrode body 10 between two convex portions 210 .

[0042] The exterior member 20 has two welded portions R20. In the present embodiment, in the welded portions R20, the laminated sheets 200 are welded via the entire non-contact portion R10A.

[0043] In the present embodiment, when the exterior member 20 is viewed from the Z-axis direction, the area SR10A of the non-contact portion R10A of the welded portion R20 (see Figure 1 ) relative to the area SR20 of the weld portion R20 (hereinafter also referred to as "ratio (SR10A / SR20)") is 10% or more.

[0044] (1.2.1) Laminated Sheet like Figure 2 As shown, the laminated sheet 200 includes a metal layer 201, an inner resin layer 202, and an outer resin layer 203. The inner resin layer 202 is laminated on a surface S201A of the metal layer 201 on the electrode body 10 side. The outer resin layer 203 is laminated on a surface S201B of the metal layer 201 on the opposite side to the electrode body 10 side.

[0045] The metal layer 201 blocks the entry and exit of gas (eg, water vapor, air, etc.) between the outside of the battery 1 and the inside of the battery 1. The material of the metal layer 201 is metal (eg, aluminum, etc.).

[0046] The inner resin layer 202 constitutes the welding portion R20. In addition, the inner resin layer 202 electrically insulates the electrode body 10, the positive electrode tab 30 and the negative electrode tab 40, and the metal layer 201. The inner resin layer 202 may contain a thermoplastic resin. As thermoplastic resins, for example, olefin resins (such as polypropylene, polyethylene, etc.), polyvinyl chloride, polyvinylidene chloride, polystyrene resins, acrylonitrile-styrene copolymer (AS) resin, acrylonitrile-butadiene-styrene copolymer (ABS) resin, polyester resin, poly (meth) acrylate resin, polyvinyl alcohol, polycarbonate resin, polyamide resin, polyimide resin, polyether resin, polyoxymethylene resin, fluororesin, polysulfone resin, polyphenylene sulfide resin, polyketone resin, etc. can be cited.

[0047] Among them, it is preferred that the thermoplastic resin contains a resin that is compatible with the separator 13. This improves the adhesion between the welding portion R20 and the separator 13. "Compatible" means that the first resin and the second resin are not separated from each other but mixed together in an atmosphere where the first resin and the second resin are melted. The resin that is compatible with the separator 13 is appropriately selected according to the material of the separator 13. When the separator 13 contains polyethylene, the inner resin layer 202 preferably contains polyethylene. When the separator 13 contains polypropylene, the inner resin layer 202 preferably contains polypropylene.

[0048] The inner resin layer 202 may contain a compounding agent as required. Examples of the compounding agent include heat stabilizers, antioxidants, pigments, weathering agents, flame retardants, plasticizers, dispersants, lubricants, release agents, and antistatic agents.

[0049] The outer resin layer 203 improves the durability of the laminate 200. The outer resin layer 203 may also contain a thermoplastic resin. The thermoplastic resin of the outer resin layer 203 is not particularly limited, and the same thermoplastic resin as the resin exemplified as the thermoplastic resin of the inner resin layer 202 may be cited. The thermoplastic resin of the outer resin layer 203 may be the same as or different from the thermoplastic resin of the inner resin layer 202. The outer resin layer 203 may also contain a compounding agent as required. As the compounding agent, for example, a heat stabilizer, an antioxidant, a pigment, a weathering agent, a flame retardant, a plasticizer, a dispersant, a lubricant, a release agent, an antistatic agent, etc. may be cited.

[0050] (1.3) Positive electrode tab The positive electrode tab 30 is electrically connected to the plurality of positive electrode sheets 11 .

[0051] The positive electrode current collector has a positive electrode lead portion extending in the positive direction of the Y axis. No positive electrode active material layer is formed in the positive electrode lead portion. The positive electrode tab 30 may be composed of only a plurality of positive electrode lead portions. The positive electrode tab 30 may also include a plurality of positive electrode lead portions and a positive electrode lead connected to the plurality of positive electrode lead portions. The length L7 of the positive electrode tab 30 in the X axis direction (see Figure 1 ) For example, 40mm~50mm.

[0052] (1.4) Negative electrode tab The negative electrode tab 40 is electrically connected to the plurality of negative electrode sheets 12 .

[0053] The negative electrode current collector has a negative electrode lead portion extending in the negative direction of the Y axis. No negative electrode active material layer is formed in the negative electrode lead portion. The negative electrode tab 40 may be composed of only a plurality of negative electrode lead portions. The negative electrode tab 40 may also include a plurality of negative electrode lead portions and a negative electrode lead connected to the plurality of negative electrode lead portions. The length L7 of the negative electrode tab 40 in the X-axis direction (see Figure 1) For example, 40mm~50mm.

[0054] (1.5) Non-aqueous electrolyte The battery 1 has a non-aqueous electrolyte. The non-aqueous electrolyte is contained in the outer casing 20 together with the electrode body 10. As the non-aqueous electrolyte, any non-aqueous electrolyte can be used as long as a supporting electrolyte (such as LiPF6, etc.) as an electrolyte is dissolved or dispersed in a non-aqueous solvent (such as ethylene carbonate, etc.). The non-aqueous electrolyte can contain various types of additives (such as lithium bis(oxalate)borate, etc.).

[0055] (1.6) Purpose The use of the battery 1 is not particularly limited, and examples thereof include a vehicle power source, a power source for an information processing device (for example, a personal computer, a smartphone, etc.), and a power source for power storage.

[0056] (1.7) Effects As reference Figure 1 and Figure 2 As shown in the description, the battery 1 includes an electrode body 10, an exterior member 20, a positive electrode tab 30, and a negative electrode tab 40. The exterior member 20 includes a laminate sheet 200. The electrode body 10 includes non-contact portions R10A at both edges in the X-axis direction. The exterior member 20 includes a welded portion R20 across the non-contact portion R10A. That is, the portions of the separator 13 corresponding to the two edges of the electrode body 10 in the X-axis direction (hereinafter also referred to as "two edges") are sandwiched between the laminate sheets 200 and fixed to the welded portion R20. Therefore, when the battery 1 is abnormally heated, the two edges of the separator 13 are less likely to shrink than when the two edges of the separator 13 are not sandwiched between the laminate sheets 200. As a result, the occurrence of a short circuit in the battery 1 is suppressed.

[0057] As reference Figure 1 and Figure 2 As shown in the description, in the battery 1, the electrode body 10 includes a plurality of positive electrode sheets 11, a plurality of negative electrode sheets 12, and a plurality of separators 13. The electrode body 10 is composed of the positive electrode sheets 11 and the negative electrode sheets 12 alternately stacked in the Z-axis direction with the separators 13 interposed therebetween. The non-contact portion R10A extends in the Y-axis direction. That is, the battery 1 is a so-called laminated type battery.

[0058] As reference Figure 1 and Figure 2 As described above, in the battery 1 , when the exterior member 20 is viewed from the Z-axis direction, the ratio (SR10A / SR20) is 10% or more. As a result, the two edges of the separator 13 in the X-axis direction are more firmly fixed at the welded portion R20 than when the ratio (SR10A / SR20) is less than 10%. Therefore, the two edges of the separator 13 in the X-axis direction are less likely to shrink when the battery 1 is abnormally heated. As a result, the occurrence of a short circuit in the battery 1 is suppressed.

[0059] As reference Figure 1 and Figure 2 As described above, in the battery 1 , the surface of the non-contact portion R10A in the welded portion R20 of the separator 13 is rougher than the surface of a portion of the separator 13 other than the non-contact portion R10A in the welded portion R20 (ie, the electrode portion R10B). As a result, the contact area between the non-contact portion R10A of the separator 13 and the welded portion R20 is larger than when the surface of the non-contact portion R10A is not rougher than the surface of the electrode portion R10B. As a result, the two edges of the separator 13 are more firmly fixed to the welded portion R20. As a result, the occurrence of a short circuit in the battery 1 is further suppressed.

[0060] As reference Figure 1 and Figure 2 As described above, in the battery 1 , the thickness of the non-contact portion R10A in the welded portion R20 of the separator 13 is thinner than the thickness of the portion of the separator 13 other than the non-contact portion R10A in the welded portion R20 (ie, the electrode portion R10B). As a result, the contact area between the non-contact portion R10A of the separator 13 and the welded portion R20 is larger than when the thickness of the non-contact portion R10A is not thinner than the thickness of the electrode portion R10B. As a result, the two edges of the separator 13 are more firmly fixed to the welded portion R20. As a result, the occurrence of a short circuit in the battery 1 is further suppressed.

[0061] (2) Module like Figure 3 and Figure 4 As shown in FIG. 1 , the module 2 according to the embodiment of the present disclosure includes a plurality of batteries 1 and a case 50 . The case 50 accommodates the plurality of batteries 1 .

[0062] like Figure 3 As shown, the module 2 is a rectangular parallelepiped object. The length L10 of the module 2 in the Y-axis direction is, for example, 350 mm to 600 mm. The length L11 of the module 2 in the Z-axis direction is, for example, 150 mm to 250 mm. The length L12 of the module 2 in the X-axis direction is, for example, 80 mm to 110 mm.

[0063] A pair of voltage terminals 61 and a connector 62 are provided at both ends of the module 2 in the Y-axis direction. A flexible printed circuit board 63 described later is connected to the connector 62. Bus bars (not shown) are welded to both ends of the module 2 in the Y-axis direction.

[0064] The housing 50 includes a housing body 51 and a housing cover 52. The housing 50 is made of an aluminum alloy. The housing 50 is formed by, for example, joining aluminum die castings at both ends of an extruded material of an aluminum alloy by laser welding or the like.

[0065] like Figure 4 As shown, a plurality of batteries 1 are accommodated in an arranged state inside the module 2. In this embodiment, 24 batteries 1 are arranged along the Z-axis direction. Adjacent batteries 1 are bonded to each other.

[0066] A flexible printed circuit (FPC) 63 is disposed on the battery 1. The flexible printed circuit 63 is formed in a strip shape with the X-axis direction as the long side direction, and thermistors 64 are provided at both ends of the flexible printed circuit 63. In the module 2, the thermistor 64 is not bonded to the battery 1, but is pressed to the battery 1 side by the case cover 52.

[0067] One or more buffers (not shown) are accommodated inside the module 2. For example, the buffer is a thin plate-shaped member that can be elastically deformed, and is arranged between adjacent batteries 1 with the arrangement direction of the batteries 1 as the thickness direction. In this embodiment, as an example, buffers are arranged at both ends and the center of the module 2 in the long side direction.

[0068] (2.2) Application examples The module 2 is suitable for use as a power source for the vehicle 300, namely a battery pack 310. Figure 5 As shown, a vehicle 300 is an electric vehicle (BEV: Battery Electric Vehicle) having a battery pack 310 mounted under the floor.

[0069] In the present embodiment, the positive X-axis direction, the positive Z-axis direction, and the positive Y-axis direction respectively indicate the upper side in the vehicle vertical direction, the front side in the vehicle front-rear direction, and the left side in the vehicle width direction.

[0070] The vehicle 300 of this embodiment, as an example, is provided with a DC / DC converter 301, an electric compressor 302, and a PTC (Positive Temperature Coefficient) heater 303 on the vehicle front side of a battery pack 310. In addition, a motor 304, a gear box 305, an inverter 306, and a charger 307 are provided on the vehicle rear side of the battery pack 310.

[0071] The DC current output from battery pack 310 is regulated in voltage by DC / DC converter 301 and then supplied to electric compressor 302, PTC heater 303, inverter 306, etc. In addition, by supplying power to motor 304 via inverter 306, rear wheels rotate and vehicle 300 travels.

[0072] A charging port 308 is provided on the right side of the rear portion of the vehicle 300 . By connecting a charging plug of an external charging device (not shown) to the charging port 308 , electric power can be stored in the battery pack 310 via the charger 307 .

[0073] In addition, the configuration and structure of each component constituting the vehicle 300 are not limited to the above-mentioned configuration. For example, it can also be applied to a hybrid vehicle (HV: Hybrid Vehicle) or a plug-in hybrid vehicle (PHEV: Plug-in Hybrid Electric Vehicle) equipped with an engine. In the present embodiment, the motor 304 is mounted on the rear of the vehicle and is a rear-wheel drive vehicle, but it is not limited to this. It can also be a front-wheel drive vehicle with the motor 304 mounted on the front of the vehicle, or it can be a pair of motors 304 mounted on the front and rear of the vehicle. In addition, it can also be a vehicle with an in-wheel motor in each wheel.

[0074] The battery pack 310 includes a plurality of modules 2. In the present embodiment, ten modules 2 are provided. Specifically, five modules 2 are arranged in the vehicle front-rear direction on the right side of the vehicle 300, and five modules 2 are arranged in the vehicle front-rear direction on the left side of the vehicle 300. The plurality of modules 2 are electrically connected to each other.

[0075] (2.3) Effects As reference Figure 1 to Figure 4 As described above, the module 2 includes a plurality of batteries 1 and a case 50 . Thus, the occurrence of a short circuit in the module 2 is suppressed.

[0076] (3) Modification In the present embodiment, the electrode body 10 has a stacked structure, but the present disclosure is not limited thereto. The electrode body of the present disclosure may also have a wound structure.

[0077] In the present embodiment, the ratio (SR10A / SR20) is 10% or more, but the present disclosure is not limited thereto. The ratio (SR10A / SR20) of the present disclosure may be less than 10%.

[0078] In the present embodiment, the surface of the non-contact portion R10A in the welded portion R20 of the separator 13 is rougher than the surface of the electrode portion R10B, but the present disclosure is not limited thereto. In the present disclosure, the surface of the non-contact portion R10A in the welded portion R20 of the separator 13 may not be rougher than the surface of the electrode portion R10B.

[0079] In the present embodiment, the thickness of the non-contacting portion R10A in the welding portion R20 of the separator 13 is thinner than the thickness of the electrode portion R10B, but the present disclosure is not limited thereto. In the present disclosure, the thickness of the non-contacting portion R10A in the welding portion R20 of the separator 13 may not be thinner than the thickness of the electrode portion R10B.

[0080] In the present embodiment, the exterior material 20 is composed of one laminate sheet 200 , but the present disclosure is not limited thereto. The exterior material 20 may be composed of a plurality of laminate sheets 200 .

[0081] In the present embodiment, the welding portion R20 welds the laminated sheets 200 through the entire non-contact portion R10A, but the present disclosure is not limited thereto. The welding portion R20 may weld the laminated sheets 200 through a portion of the non-contact portion R10A.

[0082] In the present embodiment, the exterior member 20 has a double cup-shaped convex structure, but the present disclosure is not limited thereto. The exterior member 20 may also have a single cup-shaped convex structure.

Claims

1. A battery comprising: A flat electrode body in which positive and negative electrodes are alternately stacked with separators between them; An outer casing containing the electrode body; a positive electrode tab protruding from the exterior member in a first direction perpendicular to the thickness direction of the electrode body and electrically connected to the positive electrode; and a negative electrode tab, protruding from the exterior member in the first direction or in a direction opposite to the first direction and electrically connected to the negative electrode, The outer member has at least one laminated sheet, The electrode body has non-contact portions where the positive electrode and the negative electrode do not contact the separator at two edge portions in a second direction perpendicular to the thickness direction and the first direction, The exterior member has a welding portion where the laminate sheets are welded via at least a portion of the non-contact portion.

2. The battery according to claim 1, wherein The positive electrode comprises a plurality of positive electrode sheets, The negative electrode comprises a plurality of negative electrode sheets, The separator comprises a plurality of separators. The electrode body is composed of the positive electrode sheets and the negative electrode sheets alternately stacked in the thickness direction with the separators interposed therebetween. The non-contact portion extends along the first direction.

3. The battery according to claim 1, wherein When the exterior member is viewed in the thickness direction, a ratio of an area of ​​the non-contact portion in the welded portion to an area of ​​the welded portion is 10% or more.

4. The battery according to claim 1, wherein The surface of the non-contact portion in the welded portion of the separator is rougher than the surface of a portion of the separator other than the non-contact portion in the welded portion.

5. The battery according to claim 1, wherein The thickness of the non-contact portion in the welded portion of the separator is thinner than the thickness of a portion of the separator other than the non-contact portion in the welded portion.

6. A module comprising: A plurality of batteries according to any one of claims 1 to 5; and A housing houses the plurality of batteries.

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