Electrode body and battery

Abstract

An electrode body (10) having improved electrolyte permeability with a simple structure and a battery including the electrode body are provided. An electrode body (10) comprises: a first electrode layer (11), a second electrode layer (12), and a separator (13) arranged between the first electrode layer and the second electrode layer, wherein the first electrode layer (11) has a convex portion protruding toward the separator (13), and the second electrode layer (12) has a concave portion at a position opposite to the convex portion of the first electrode layer (11).

Description

Technical Field

[0001] The present disclosure relates to an electrode body and a battery. Background Art

[0002] Lithium-ion secondary batteries are generally manufactured by injecting an electrolyte into an outer body, which contains an electrode body including an electrode and a separator. In order to increase the electrode density, the electrode body is subjected to a process such as high-pressure pressing and bonding the electrode and the separator with an adhesive. Due to this treatment, it becomes difficult for the electrolyte to penetrate into the electrode body, and improving the efficiency of the injection operation has become a problem.

[0003] As a method for improving the permeability of the electrolyte solution into the electrode body, for example, Japanese Patent Application Laid-Open No. 2002-15773 proposes providing a portion where the electrode and the separator are not bonded when bonding the electrode and the separator constituting the electrode body.

[0004] The method described in Japanese Patent Application Laid-Open No. 2002-15773 requires a step of providing a portion where the electrode and the separator are not bonded together in order to improve the permeability of the electrolyte, and thus there is room for improvement in terms of working efficiency. Summary of the invention

[0005] In view of the above circumstances, an object of one embodiment of the present disclosure is to provide an electrode body having improved electrolyte permeability with a simple structure, and a battery including the electrode body.

[0006] Means for solving the above-mentioned problems include the following embodiments.

[0007] <1> An electrode body comprises a first electrode layer, a second electrode layer, and a separator arranged between the first electrode layer and the second electrode layer.

[0008] The first electrode layer has a convex portion protruding toward the diaphragm side,

[0009] The second electrode layer has a concave portion at a position facing the convex portion of the first electrode layer.

[0010] <2> according to <1> In the electrode body, a density of a region corresponding to the protrusion of the first electrode layer is lower than a density of a region around the protrusion.

[0011] <3> according to <1> or <2> In the electrode body, the density of a region corresponding to the concave portion of the second electrode layer is greater than the density of a region around the concave portion.

[0012] <4> according to <1> ~ <3> In the electrode body described above, the first electrode layer is a negative electrode layer, and the second electrode layer is a positive electrode layer.

[0013] <5> according to <1> ~ <4> The electrode body described in any one of the above

[0014] The second electrode layer has a convex portion protruding toward the diaphragm side,

[0015] The first electrode layer has a concave portion at a position facing the convex portion of the second electrode layer.

[0016] <6> A battery comprising <1> ~ <5> The electrode body described in any one of the above.

[0017] According to one embodiment of the present disclosure, there are provided an electrode body having improved electrolyte permeability with a simple structure, and a battery including the electrode body. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a cross-sectional view schematically showing an example of the structure of an electrode body.

[0019] Figure 2 This is a cross-sectional view schematically showing an example of the structure of an electrode body.

[0020] Figure 3 This is a diagram schematically showing an example of application of a battery in an electric vehicle.

[0021] Figure 4 This is a diagram schematically showing an example of the structure of a battery module.

[0022] Figure 5 This is a diagram schematically showing an example of the structure of a battery module.

[0023] Figure 6 This is a diagram schematically showing an example of the structure of a battery cell included in a battery module. DETAILED DESCRIPTION

[0024] In the present disclosure, a numerical range expressed using "to" means a range including the numerical values ​​described before and after "to" as the minimum value and the maximum value, respectively.

[0025] In the numerical ranges recorded in stages in the present disclosure, the upper limit or lower limit recorded in a certain numerical range may also be replaced by the upper limit or lower limit of another numerical range recorded in stages. In the numerical ranges recorded in the present disclosure, the upper limit or lower limit recorded in a certain numerical range may also be replaced by the value shown in the embodiments.

[0026] In the present disclosure, the term "process" includes not only an independent process but also a process that cannot be clearly distinguished from other processes as long as the intended purpose of the process can be achieved.

[0027] In the present disclosure, when an embodiment is described with reference to the drawings, the configuration of the embodiment is not limited to the configuration shown in the drawings. In addition, the sizes of components in each figure are conceptual, and the relative relationship between the sizes of the components is not limited to this.

[0028] <Electrode body>

[0029] The electrode body disclosed in the present invention includes a first electrode layer, a second electrode layer, and a separator disposed between the first electrode layer and the second electrode layer.

[0030] The first electrode layer has a convex portion protruding toward the diaphragm side,

[0031] The second electrode layer has a concave portion at a position facing the convex portion of the first electrode layer.

[0032] In a general method of manufacturing a battery, an electrolyte is injected into an outer casing containing an electrode body, and the electrolyte is allowed to permeate into the electrode body. At this time, in order to promote the permeation of the electrolyte, the interior of the outer casing is sometimes depressurized before the electrolyte is injected.

[0033] However, in the case of applying pressure to increase the density of the electrode body, the degassing of the electrode body cannot be fully performed, and the pressure difference between the inside and outside of the outer body may not be sufficiently ensured. As a result, the electrolyte penetration promotion effect brought about by the reduced pressure may not be fully exerted.

[0034] In the electrode body disclosed herein, the region corresponding to the protrusion of the first electrode layer becomes a branch of air, and the interior of the electrode body is effectively decompressed. As a result, the pressure difference between the interior and exterior of the outer casing is sufficiently ensured, and the penetration of the electrolyte into the electrode body is promoted.

[0035] (1st electrode layer)

[0036] The first electrode layer has a protrusion protruding toward the separator side.

[0037] From the viewpoint of allowing the region corresponding to the protrusion of the first electrode layer to effectively function as a branch flow of air, the density of the region corresponding to the protrusion of the first electrode layer is preferably smaller than the density of the region around the protrusion.

[0038] A state in which the density of the area corresponding to the protrusion of the first electrode layer is lower than the density of the surrounding area can be formed by, for example, making the pressure applied to the area corresponding to the protrusion lower than the pressure applied to the area around the protrusion when the first electrode layer is subjected to a pressurization treatment, or by not applying pressure to the area corresponding to the protrusion.

[0039] As a method for forming the convex portion on the first electrode layer, there is a method of pressing the first electrode layer using a roller having concave portions on its surface. According to this method, the convex portion can be formed at the portion of the first electrode layer where the concave portion of the roller passes (i.e., the portion not pressed by the roller or where the pressing force is relatively weak).

[0040] From the viewpoint of allowing the region corresponding to the protrusion of the first electrode layer to effectively function as a branch flow of air, the shape of the protrusion when the first electrode layer is viewed from the main surface is preferably linear, more preferably straight.

[0041] When the projections are linear, the ends (preferably both ends) of the projections are preferably present on the end surface of the electrode body.

[0042] The number of the protrusions provided on the first electrode layer is not particularly limited, and may be one or more.

[0043] For example, the first electrode layer may be in a state where a plurality of linear protrusions are provided in a stripe shape or a grid shape.

[0044] The ratio of the protrusions to the main surface of the first electrode layer is not particularly limited.

[0045] From the viewpoint of effectively degassing the inside of the electrode body, the ratio of the area of ​​the protrusions to the main surface area of ​​the first electrode layer is preferably 1% or more, more preferably 5% or more, and even more preferably 10% or more.

[0046] From the viewpoint of ensuring the energy density of the battery, the ratio of the area of ​​the protrusions to the main surface area of ​​the first electrode layer is preferably 30% or less, more preferably 25% or less, and even more preferably 20% or less.

[0047] When there are a plurality of protrusions provided on the first electrode layer, the area of ​​the protrusions is the total area of ​​the areas of the plurality of protrusions.

[0048] The thickness of the first electrode layer is not particularly limited and can be selected from the thicknesses of common electrode layers.

[0049] For example, the thickness of the region around the protrusion of the first electrode layer can be selected from the range of 10 μm to 200 μm.

[0050] The thickness of the region corresponding to the protrusion of the first electrode layer is not particularly limited.

[0051] For example, the thickness of the region corresponding to the protrusion of the first electrode layer can be selected from a range of 110% to 150% of the thickness of the region around the protrusion of the first electrode layer.

[0052] The electrode body may include a plurality of first electrode layers. In this case, some of the plurality of first electrode layers may have the protrusions, or all of the first electrode layers may have the protrusions.

[0053] (Second electrode layer)

[0054] The second electrode layer has a concave portion at a position facing the convex portion of the first electrode layer.

[0055] Since the second electrode layer has the recessed portion at a position facing the raised portion of the first electrode layer, the thickness of the electrode body including the first electrode layer, the second electrode layer, and the separator is made uniform.

[0056] As a method of forming the recessed portion in the second electrode layer, there is a method of pressing the second electrode layer using a roller having a convex portion on its surface. According to this method, the recessed portion can be formed at the portion of the second electrode layer where the convex portion of the roller passes.

[0057] The shape of the recessed portion provided in the second electrode layer is preferably set to a shape corresponding to the convex portion arranged in the first electrode layer. For example, when the convex portion provided in the first electrode layer is linear, the recessed portion provided in the second electrode layer is preferably also linear.

[0058] The thickness of the second electrode layer is not particularly limited and can be selected from the thicknesses of common electrode layers.

[0059] For example, the thickness of the region around the recessed portion of the second electrode layer can be selected from a range of 10 μm to 200 μm.

[0060] The thickness of the region corresponding to the concave portion of the second electrode layer is not particularly limited.

[0061] For example, the thickness of the region corresponding to the concave portion of the second electrode layer can be selected from a range of 50% to 90% of the thickness of the region around the concave portion of the second electrode layer.

[0062] The electrode body may include a plurality of second electrode layers. In this case, some of the plurality of second electrode layers may have the recessed portion, or all of the second electrode layers may have the recessed portion.

[0063] The second electrode layer may have a convex portion protruding toward the separator side in addition to the above-mentioned concave portion. In this case, the first electrode layer may have a concave portion at a position facing the convex portion of the second electrode layer.

[0064] When the second electrode layer has a protrusion, the details and preferred embodiments thereof are the same as those of the protrusion of the first electrode layer.

[0065] When the first electrode layer has a concave portion, the details and preferred embodiments thereof are the same as the details and preferred embodiments of the concave portion of the second electrode layer.

[0066] (Diaphragm)

[0067] The separator is disposed between the first electrode layer and the second electrode layer.

[0068] The type of the separator is not particularly limited, and can be selected from separators commonly used as separators for electrodes. For example, a microporous film made of a resin such as polyethylene can be used.

[0069] It is preferable that the separator can be sufficiently deformed in accordance with the shapes of the protrusions of the first electrode layer and the recesses of the second electrode layer.

[0070] The thickness of the separator can be selected from the range of 5 μm to 100 μm, for example.

[0071] (Active substance)

[0072] The first electrode layer and the second electrode layer contain any one of a negative electrode active material and a positive electrode active material.

[0073] When the first electrode layer is a negative electrode layer containing a negative electrode active material, the second electrode layer is a positive electrode layer containing a positive electrode active material. When the first electrode layer is a positive electrode layer containing a positive electrode active material, the second electrode layer is a negative electrode layer containing a negative electrode active material.

[0074] From the viewpoint of making the protrusions of the first electrode layer function as branch flows of air, the first electrode layer is preferably a negative electrode layer.

[0075] The type of the negative electrode active material is not particularly limited, and it can be selected from materials generally used as negative electrode active materials for batteries.

[0076] Specific examples of the negative electrode active material include carbon materials, silicon, etc. Examples of the carbon material include graphite, soft carbon, and hard carbon.

[0077] The negative electrode active material contained in the negative electrode layer may be a single type or two or more types.

[0078] The particle size of the negative electrode active material is not particularly limited, and can be selected from the range of 5 μm to 30 μm, for example.

[0079] The type of the positive electrode active material is not particularly limited, and it can be selected from materials commonly used as positive electrode active materials for batteries.

[0080] As the positive electrode active material, a composite oxide composed of lithium and a transition metal and other metals that may be optionally contained (hereinafter also referred to as a lithium transition metal composite oxide) can be cited. As transition metals and other metals, Ni, Co, Mn, Al, B, Mg, Ti, V, Cr, Fe, Cu, Zn, Ga, Sr, Zr, Nb, In, Sn, Ta, W, etc. can be cited. Among them, preferably containing at least one lithium transition metal composite oxide selected from Ni, Co and Mn, more preferably containing Ni, Co and Mn lithium transition metal composite oxide (NCM, nickel cobalt manganese oxide).

[0081] Specific examples of lithium transition metal composite oxides include lithium cobalt oxide (LiCoO2), lithium nickel oxide (LiNiO2), lithium manganese oxide (LiMnO2), and composite oxides thereof (LiCo x Ni y Mn z O2, x+y+z=1), and a composite oxide (LiCo a Ni b Mn c M' d O2, a+b+c+d=1, M': Al, Mg, Ti, Zr or Ge), spinel lithium manganese oxide (LiMn2O4), olivine LiMPO4 (M: Co, Ni, Mn, Fe), etc.

[0082] The positive electrode active material contained in the positive electrode layer may be a single type or two or more types.

[0083] The particle size of the positive electrode active material is not particularly limited, and can be selected from the range of 5 μm to 30 μm, for example.

[0084] The first electrode layer and the second electrode layer may contain a conductive material as necessary.

[0085] Specific examples of the conductive material include carbon materials such as carbon black (acetylene black, thermal black, furnace black, etc.), carbon nanotubes, and graphite.

[0086] The conductive material contained in the first electrode layer and the second electrode layer may be a single type or two or more types.

[0087] The first electrode layer and the second electrode layer may contain a binder as necessary.

[0088] Specific examples of the binder include polyvinylidene fluoride (PVdF), polyethylene, polypropylene, polyethylene terephthalate, cellulose, nitrocellulose, carboxymethyl cellulose, polyethylene oxide, polyepichlorohydrin, polyacrylonitrile, styrene-butadiene rubber (SBR), acrylonitrile-butadiene rubber (NBR), polyacrylate, polymethacrylate, polytetrafluoroethylene (PTFE), and the like.

[0089] The conductive material contained in the first electrode layer and the second electrode layer may be a single type or two or more types.

[0090] (Current Collector)

[0091] The electrode body of the present disclosure may include a first current collector in contact with the surface of the first electrode layer opposite to the surface facing the separator.

[0092] The electrode body of the present disclosure may include a second current collector in contact with the surface of the second electrode layer opposite to the surface facing the separator.

[0093] The types of the first collector and the second collector are not particularly limited and can be selected from collectors commonly used as collectors for electrodes. For example, a collector containing copper can be used as a collector for the negative electrode, and a collector containing aluminum can be used as a collector for the positive electrode.

[0094] The thickness of the current collector can be selected from the range of 5 μm to 50 μm, for example.

[0095] (Method for producing electrode layer)

[0096] The method for producing the electrode layer is not particularly limited and can be selected from known methods.

[0097] For example, an electrode mixture containing an active material may be applied to one or both surfaces of a current collector to form an electrode layer.

[0098] The electrode layer may be subjected to a pressure treatment to increase its density. At this time, the pressure applied to a specific region of the electrode layer may be reduced or not applied to the specific region, thereby forming a convex portion in the region of the electrode layer.

[0099] An example of the structure of the electrode body disclosed in the present invention is shown in Figure 1 .

[0100] Figure 1 The electrode body 10 shown includes a first electrode layer 11 , a second electrode layer 12 , and a separator 13 disposed therebetween.

[0101] A first current collector 14 is disposed on the surface of the first electrode layer 11 opposite to the surface facing the separator 13 .

[0102] A second current collector 15 is disposed on the surface of the second electrode layer 12 opposite to the surface facing the separator 13 .

[0103] The first electrode layer 11 has a convex portion protruding toward the separator 13 , and the second electrode layer 12 has a concave portion at a position facing the convex portion of the first electrode layer 11 .

[0104] The density of the region X1 corresponding to the protrusion of the first electrode layer 11 is lower than the density of the region Y1 around the protrusion.

[0105] The density of the region X2 corresponding to the concave portion of the second electrode layer 12 is greater than the density of the region X2 around the concave portion.

[0106] Another example of the structure of the electrode body disclosed in the present invention is shown in Figure 2 .

[0107] Figure 2 The electrode body 20 shown includes a first electrode layer 21 , a second electrode layer 22 , and a separator 23 disposed therebetween.

[0108] A first current collector 24 is disposed on the surface of the first electrode layer 21 opposite to the surface facing the separator 23 .

[0109] A second current collector 25 is disposed on the surface of the second electrode layer 22 opposite to the surface facing the separator 23 .

[0110] The second electrode layer 22 has a convex portion protruding toward the separator 23 in addition to a concave portion at a position facing the convex portion of the first electrode layer 21. The first electrode layer 21 has a concave portion at a position facing the convex portion of the second electrode layer 22.

[0111] <Battery>

[0112] The battery of the present disclosure is a battery including the electrode body of the present disclosure described above.

[0113] For example, the battery of the present disclosure includes an electrode body, an outer casing that houses the electrode body, and an electrolyte solution.

[0114] (outer body)

[0115] The type of the outer casing for housing the electrode assembly is not particularly limited and can be selected according to the type of battery.

[0116] In one embodiment, a sheet-like outer casing may be used.

[0117] As the sheet-like outer casing, an outer casing containing metal can be cited. Specifically, a laminate having a metal layer containing a metal such as aluminum and a heat-sealing layer containing a resin melted by heating (so-called laminated film) can be cited. That is, the battery of the present disclosure can also be a battery using a laminated film as an outer casing (so-called laminated battery).

[0118] The outer casing may be a single member or may be composed of two or more members. For example, when the outer casing is a sheet-like object, the outer casing may be composed of a single sheet-like object or may be composed of two sheet-like objects.

[0119] If necessary, a recessed portion for housing the electrode assembly may be formed in the sheet-like exterior body by embossing.

[0120] As a method of housing the electrode assembly in the outer casing using the sheet-like outer casing, for example, the following method 1 and method 2 can be cited.

[0121] Method 1: A method of joining the outer casing around the electrode body while placing the electrode body between one outer casing folded in half or between two outer casings stacked together

[0122] Method 2: The electrode assembly is placed in a bag made by joining the peripheries of a folded outer casing or two overlapped outer casings.

[0123] (Electrolyte)

[0124] The type of electrolyte is not particularly limited and can be selected according to the type of battery.

[0125] As the electrolyte solution, for example, an electrolyte solution obtained by dissolving an electrolyte such as LiPF 6 in a non-aqueous solvent can be used.

[0126] The battery of the present disclosure can be mounted on an electric vehicle. Hereinafter, an example of applying the battery of the present disclosure to an electric vehicle will be described with reference to the accompanying drawings. In the following description, "battery unit 20" is equivalent to the battery of the present disclosure.

[0127] Figure 3 1 is a schematic top view showing the main parts of a vehicle 100 to which the battery pack 10 according to the embodiment is applied. Figure 3 As shown, the vehicle 100 is an electric vehicle (BEV) equipped with a battery pack 10 under the cab. In addition, the arrows UP, FR, and LH in each figure respectively indicate the upper side in the vehicle vertical direction, the front side in the vehicle front-back direction, and the left side in the vehicle width direction. When the directions of front, back, left, right, up, and down are used for description, unless otherwise specified, they indicate the front and back in the vehicle front-back direction, the left and right in the vehicle width direction, and the up and down in the vehicle vertical direction.

[0128] As an example of a vehicle 100 of the present embodiment, a DC / DC converter 102, an electric compressor 104, and a PTC (Positive Temperature Coefficient) heater 106 are arranged on the front side of the vehicle relative to the battery pack 10. In addition, a motor 108, a gear box 110, an inverter 112, and a charger 114 are arranged on the rear side of the vehicle relative to the battery pack 10.

[0129] The DC current output from battery pack 10 is regulated in voltage by DC / DC converter 102 and then supplied to electric compressor 104, PTC heater 106, inverter 112, etc. In addition, by supplying power to motor 108 via inverter 112, rear wheels are rotated and vehicle 100 travels.

[0130] A charging port 116 is provided on the right side of the rear portion of the vehicle 100 . By connecting a charging plug of an external charging device (not shown) to the charging port 116 , electric power can be stored in the battery pack 10 via the charger 114 .

[0131] The configuration and structure of each component constituting the vehicle 100 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 addition, in the present embodiment, the motor 108 is mounted on the rear of the vehicle to drive the rear wheels, but it is not limited to this. It can also be a front-wheel drive vehicle with the motor 108 mounted on the front of the vehicle, and a pair of motors 108 can be mounted on the front and rear of the vehicle. In addition, it can also be a vehicle with an in-wheel motor on each wheel.

[0132] The battery pack 10 is composed of a plurality of battery modules 11. In the present embodiment, as an example, 10 battery modules 11 are provided. Specifically, five battery modules 11 are arranged along the front-rear direction of the vehicle on the right side of the vehicle 100, and five battery modules 11 are arranged along the front-rear direction of the vehicle on the left side of the vehicle 100. In addition, each battery module 11 is electrically connected.

[0133] Figure 4 1 is a schematic three-dimensional diagram of the battery module 11. Figure 4 As shown, the battery module 11 is formed into a substantially rectangular parallelepiped shape with the vehicle width direction as the long side direction. In addition, the outer shell of the battery module 11 is formed of an aluminum alloy. For example, an aluminum die casting is joined to both ends of an aluminum alloy pressing member by laser welding or the like, thereby forming the outer shell of the battery module 11.

[0134] A pair of voltage terminals 12 and a connector 14 are provided at both ends of the battery module 11 in the vehicle width direction. A flexible printed circuit board 21 described later is connected to the connector 14. Bus bars (not shown) are welded to both ends of the battery module 11 in the vehicle width direction.

[0135] The battery module 11 has a length MW in the vehicle width direction of, for example, 350 mm to 600 mm, a length ML in the vehicle front-rear direction of, for example, 150 mm to 250 mm, and a height MH in the vehicle vertical direction of, for example, 80 mm to 110 mm.

[0136] Figure 5 FIG. 1 is a top view of the battery module 11 with the upper cover removed. Figure 5 As shown, a plurality of battery cells 20 are housed in an aligned state inside the battery module 11. In the present embodiment, as an example, 24 battery cells 20 are aligned in the vehicle front-rear direction and bonded to each other.

[0137] A flexible printed circuit (FPC) 21 is disposed on the battery cell 20. The flexible printed circuit 21 is formed in a strip shape with the vehicle width direction as the long side direction, and thermistors 23 are provided at both ends of the flexible printed circuit 21. The thermistors 23 are not bonded to the battery cell 20, but are pressed toward the battery cell 20 by the upper cover of the battery module 11.

[0138] In addition, one or more buffers (not shown) are stored inside the battery module 11. For example, the buffer is a thin plate-shaped member that can be elastically deformed, and is arranged between adjacent battery cells 20 with the arrangement direction of the battery cells 20 as the thickness direction. In this embodiment, as an example, buffers are arranged at both ends and the center of the battery module 11 in the long side direction.

[0139] Figure 6 2 is a schematic diagram of the battery cell 20 housed in the battery module 11 as viewed from the thickness direction. Figure 6 As shown, the battery cell 20 is formed in a substantially rectangular plate shape, and an electrode body (not shown) is accommodated therein. The electrode body is formed by laminating a positive electrode, a negative electrode, and a separator, and is sealed by a laminate film 22 .

[0140] In this embodiment, as an example, the storage part of the electrode body is formed by folding and laminating the embossed sheet-shaped laminate film 22. In addition, two structures, a single cup embossed structure with embossing at one place and a double cup embossed structure with embossing at two places, can be adopted, but in this embodiment, a single cup embossed structure with a drawing depth of about 8 mm to 10 mm is adopted.

[0141] The upper ends of both ends of the battery cell 20 in the longitudinal direction are bent to form an angular shape. In addition, the upper end of the battery cell 20 is bent, and a fixing band 24 is wound around the upper end of the battery cell 20 along the longitudinal direction.

[0142] Here, terminals (tabs) 26 are provided at both ends in the longitudinal direction of the battery cell 20. In this embodiment, as an example, the terminals 26 are arranged below the vertical center of the battery cell 20. The terminals 26 are joined to a bus bar (not shown) by laser welding or the like.

[0143] The length CW1 of the battery cell 20 in the vehicle width direction is, for example, 530 mm to 600 mm, 600 mm to 700 mm, 700 mm to 800 mm, 800 mm to 900 mm, or 1000 mm or more, the length CW2 of the region where the electrode body is stored is, for example, 500 mm to 520 mm, 600 mm to 700 mm, 700 mm to 800 mm, 800 mm to 900 mm, or 1000 mm or more, and the height CH of the battery cell 20 is, for example, 80 mm to 110 mm, 110 mm to 140 mm. In addition, the thickness of the battery cell 20 is 5.0 mm to 7.0 mm, 7.0 mm to 9.0 mm, or 9.0 mm to 11.0 mm, and the height TH of the terminal 26 is 40 mm to 50 mm, 50 mm to 60 mm, or 60 mm to 70 mm.

Claims

1. An electrode body, The invention comprises a first electrode layer, a second electrode layer, and a separator arranged between the first electrode layer and the second electrode layer, wherein the first electrode layer has a convex portion protruding toward the separator. The second electrode layer has a concave portion at a position facing the convex portion of the first electrode layer.

2. The electrode body according to claim 1, The density of the region corresponding to the protrusion of the first electrode layer is lower than the density of the region around the protrusion.

3. The electrode body according to claim 1, The density of the region corresponding to the concave portion of the second electrode layer is higher than the density of the region around the concave portion.

4. The electrode body according to claim 1, The first electrode layer is a negative electrode layer, and the second electrode layer is a positive electrode layer.

5. The electrode body according to claim 1, The second electrode layer has a convex portion protruding toward the diaphragm side, The first electrode layer has a concave portion at a position facing the convex portion of the second electrode layer. 6 . A battery comprising the electrode body according to claim 1 .

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