Electrode, battery, and method for manufacturing positive electrode

Abstract

The invention provides an electrode, a battery and a manufacturing method of a positive electrode. An electrode (positive electrode 100) has a collector layer (positive electrode collector layer 110), an active material layer (positive electrode active material layer 120), and an intermediate layer (130). An active material layer (positive electrode active material layer 120) and a collector layer (positive electrode collector layer 110) are laminated and bonded, and the active material layer contains an active material (positive electrode active material 121). The intermediate layer (130) is provided between the end (110b) side of the collector layer (positive electrode collector layer (110)) and the end (120b) of the active material layer (positive electrode active material layer (120)) in the lamination direction (Z), and is bonded to the collector layer (positive electrode collector layer (110)) and the active material layer (positive electrode active material layer (120)).

Description

Technical Field

[0001] The invention relates to an electrode, a battery and a method for manufacturing a positive electrode. Background Art

[0002] Conventionally, there is known a technique involving an electrode in which an active material layer is bonded to a current collecting layer (see, for example, Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent No. 3613400 Summary of the invention

[0006] Problems to be solved by the invention

[0007] There is a demand for an electrode in which the end portion of the active material layer is prevented from being relatively thicker than other portions.

[0008] Means for solving problems

[0009] The electrode of the present invention comprises a current collecting layer, an active material layer, and an intermediate layer. The active material layer contains an active material and is laminated and bonded to the current collecting layer. The intermediate layer is arranged in the middle of one end of the current collecting layer and the end of the active material layer along the lamination direction, and is bonded to the current collecting layer and the active material layer.

[0010] The battery of the present invention comprises a positive electrode, a negative electrode, and an insulator provided between the positive electrode and the negative electrode. At least one of the positive electrode and the negative electrode is the electrode.

[0011] The manufacturing method of the positive electrode of the present invention is a manufacturing method of the following positive electrode, the positive electrode comprising: a positive electrode collector layer; a positive electrode active material layer containing a positive electrode active material and laminated and bonded to the positive electrode collector layer; and an intermediate layer provided between one end of the positive electrode collector layer and the end of the positive electrode active material layer along the lamination direction and bonded to the positive electrode collector layer and the positive electrode active material layer. In the manufacturing method of the positive electrode, the positive electrode collector layer containing aluminum is used. In addition, in the manufacturing method of the positive electrode, an intermediate layer slurry containing particles and a volatile solvent and constituting the intermediate layer after being applied on the positive electrode collector layer is used. In addition, in the manufacturing method of the positive electrode, a positive electrode active material layer slurry containing the positive electrode active material and the volatile solvent and constituting the positive electrode active material layer after being applied on the positive electrode collector layer and the intermediate layer slurry is used. The manufacturing method of the positive electrode has a coating step of coating the intermediate layer slurry and the positive electrode active material layer slurry. In the coating step, the intermediate layer slurry is coated on the positive electrode current collecting layer so as to set the contact angle to be 1° or more and 35° or less, and the positive electrode active material layer slurry is coated on the positive electrode current collecting layer and the intermediate layer slurry.

[0012] Effects of the Invention

[0013] It is possible to obtain an electrode in which the end portion of the active material layer is suppressed from being relatively thicker than other portions, and a battery having such an electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a perspective view showing the battery 1 according to the first embodiment.

[0015] Figure 2 It is a perspective view showing the charging and discharging body 10 of the battery 1 .

[0016] Figure 3 Yes means Figure 2 3A-3B is a cross-sectional view of the charge-discharge body 10.

[0017] Figure 4 Yes means Figure 3 4 is a cross-sectional view of the charge-discharge body 10 in the region 4.

[0018] Figure 5 It is a side view schematically showing a method for manufacturing the positive electrode 100 .

[0019] Figure 6 It is a schematic representation of Figure 5 A top view of the coating state of the slurry of the positive electrode collector layer 110.

[0020] Figure 7It is a side view schematically showing a coating state of a positive electrode active material layer slurry 1100 and an intermediate layer slurry 1200 coated on a positive electrode current collecting layer 110 .

[0021] Figure 8 It is a graph showing the measurement results of the outer shapes of the positive electrode active material layer 120 of the positive electrode 100 of the first embodiment and the positive electrode active material layer of a comparative example.

[0022] Fig. 9 It is a cross-sectional view showing a charging and discharging body 20 of a battery according to a second embodiment.

[0023] Fig.10 It is a cross-sectional view showing a charging and discharging body 30 of a battery according to a third embodiment. DETAILED DESCRIPTION

[0024] The embodiments for implementing the present invention are described with reference to the accompanying drawings. In order to make each embodiment easy to understand, in each figure, there is a case where the size or ratio of the constituent parts is exaggerated. In the cross-sectional view of the active material layer, the adjacent active materials are illustrated in a non-contact state, and the binder or additive material around the active material is illustrated. In each figure, the same symbol is attached to the same structure. The short side direction X of the positive electrode 100, the negative electrode 200 and the separator 300 in the stacked state is shown by an arrow. The long side direction Y of the positive electrode 100, the negative electrode 200 and the separator 300 in the stacked state is shown by an arrow. The stacking direction Z of the positive electrode 100, the negative electrode 200 and the separator 300 in the stacked state is shown by an arrow.

[0025] The electrode of the embodiment corresponding to the present invention is assumed to be a positive electrode for description. The electrode of the embodiment corresponding to the present invention also includes a negative electrode. The battery 1 of the embodiment corresponding to the present invention is assumed to be a rectangular parallelepiped battery for description. The battery 1 of the embodiment corresponding to the present invention also includes a cylindrical battery.

[0026] (Structure of Battery 1 Including Positive Electrode 100 of First Embodiment)

[0027] For the structure of the battery 1 including the positive electrode 100 of the first embodiment, refer to Figures 1 to 4 Provide explanation.

[0028] Figure 1 It is a perspective view showing the battery 1 according to the first embodiment. Figure 2 It is a perspective view showing the charging and discharging body 10 of the battery 1 . Figure 3 Yes means Figure 2 3A-3B is a cross-sectional view of the charge-discharge body 10. Figure 4 Yes means Figure 3 4 is a cross-sectional view of the charge-discharge body 10 in the region 4.

[0029] The battery 1 is, for example, a lithium ion secondary battery. Figures 1 to 4 As shown, the battery 1 includes a charging and discharging body 10, an outer casing 50, and an external terminal 60. Hereinafter, the main components of the battery 1 will be described.

[0030] The charging and discharging body 10 is charged and discharged. Figure 2 and Figure 3 The charge-discharge body 10 shown includes a positive electrode 100, a negative electrode 200, a separator 300, and an electrolyte (so-called electrolyte solution). The charge-discharge body 10 is formed by, for example, stacking the positive electrode 100, the negative electrode 200, and two separators 300 in the order of the positive electrode 100, the separator 300, the negative electrode 200, and the separator 300, and winding them into a rectangular parallelepiped shape. The charge-discharge body 10 is particularly impregnated with the electrolyte in the separator 300. The charge-discharge body 10 is covered with an insulating sheet in a state where the positive electrode collector plate and the negative electrode collector plate are joined.

[0031] Positive electrode 100 (electrode) such as Figure 3 As shown, it includes a positive electrode collector layer 110 , a positive electrode active material layer 120 and an intermediate layer 130 .

[0032] The positive electrode collector layer 110 (collector layer) is, for example, configured in a long strip shape. That is, the positive electrode collector layer 110 is formed in a foil shape. At one end of the short side direction X of the positive electrode collector layer 110, a positive electrode collector portion 110a is provided along the long side direction Y. The positive electrode collector layer 110 is, for example, formed of aluminum or an aluminum alloy. As the positive electrode collector layer 110, for example, A3003 of the JIS standard is used. A3003 is a non-heat-treatable Al-Mn alloy. The thickness of the positive electrode collector layer 110 along the stacking direction Z is, for example, 10 μm. The thickness of the positive electrode collector layer 110 is, for example, selected within the range of 5 μm to 30 μm.

[0033] The positive electrode active material layer 120 (active material layer) is provided on the positive electrode current collector layer 110. The positive electrode active material layer 120 is stacked and bonded to both sides of the positive electrode current collector layer 110, and faces each other along the stacking direction Z. The thickness of the positive electrode active material layer 120 along the stacking direction Z is, for example, 30 μm or 40 μm. The thickness of the positive electrode active material layer 120 is, for example, selected within the range of 10 μm to 200 μm.

[0034] The positive electrode active material layer 120 contains a positive electrode active material 121 , a positive electrode binder 122 , and a positive electrode conductive aid 123 .

[0035] As the positive electrode active material 121 (active material), for example, a lithium-containing composite oxide is used. The lithium-containing composite oxide is, for example, a metal element such as nickel (Ni), cobalt (Co) and manganese (Mn), and lithium (Li). The positive electrode active material 121 is formed into particles. The average particle size (D50) of the positive electrode active material 121 is, for example, 25 μm. The average particle size (D50) of the positive electrode active material 121 is, for example, selected within the range of 1 μm to 50 μm.

[0036] The positive electrode binder 122 binds the positive electrode active materials 121. As the positive electrode binder 122, for example, polyvinylidene fluoride (PVdF / polyvinylidene fluoride), polytetrafluoroethylene (PTFE), polyethylene (PE), polystyrene, polybutadiene, polyacrylonitrile, polyvinyl fluoride, polypropylene fluoride, polychloroprene fluoride, butyl rubber, nitrile rubber, styrene butadiene rubber (SBR), polysulfide rubber, nitrocellulose, cyanoethyl cellulose, various latexes, acrylic resins, or mixtures thereof are used.

[0037] The positive electrode conductive aid 123 improves the characteristics of the positive electrode 100. The positive electrode conductive aid 123 is mixed with the positive electrode active material 121 to improve the conductivity between the positive electrode collector layer 110 and the positive electrode active material 121. That is, the positive electrode conductive aid 123 ensures the conductive path between the positive electrode collector layer 110 and the positive electrode active material 121 in the positive electrode 100. As the positive electrode conductive aid 123, for example, a carbon-based material is used. Carbon-based materials are, for example, crystalline carbon, amorphous carbon, or a mixture thereof. Crystalline carbon is, for example, artificial graphite, natural graphite, or a mixture thereof. Natural graphite is, for example, flaky graphite, blocky graphite, and earthy graphite. Amorphous carbon is, for example, carbon black. Carbon black is, for example, acetylene black, Ketjen black, channel black, furnace black, lamp black, thermal black, or a mixture thereof.

[0038] The middle layer 130 (middle layer) is as follows Figure 4 As shown, the intermediate layer 130 is disposed between the end 110 b of the positive electrode collector layer 110 and the end 120 b of the positive electrode active material layer 120 in the stacking direction Z. The intermediate layer 130 is bonded to the positive electrode collector layer 110 and the positive electrode active material layer 120 .

[0039] The middle layer 130 is as follows Figure 4As shown, the intermediate layer 130 straddles the end 120b of the positive electrode active material layer 120 along the short side direction X (crossing direction) intersecting the stacking direction Z and is bonded to the positive electrode collector layer 110. The intermediate layer 130 straddles the end 120b of the positive electrode active material layer 120, which means that the intermediate layer 130 straddles the side 120a of the positive electrode active material layer 120. In the intermediate layer 130, the first length L1 of the portion away from the positive electrode active material layer 120 along the short side direction X is longer than the second length L2 of the portion bonded to the positive electrode active material layer 120 along the short side direction X. The portion away from the positive electrode active material layer 120 is a portion bonded only to the positive electrode collector layer 110. The portion bonded to the positive electrode active material layer 120 is a portion bonded to both the positive electrode collector layer 110 and the positive electrode active material layer 120. The intermediate layer 130 faces the negative electrode active material layer 220 of the negative electrode 200 via the separator 330. A thickness t1 of the intermediate layer 130 in the stacking direction Z in a region bonded to the positive electrode active material layer 120 is not less than 1 / 10 and not more than 1 / 2 of a thickness t2 of the positive electrode active material layer 120 in the stacking direction Z.

[0040] In the middle layer 130, Figure 4 The depicted material contains particles 131 , a binder 132 and an additive 133 .

[0041] Particles 131 are inorganic or organic. Particles 131 are, for example, alumina or boehmite. Organic particles are easier to disperse in a solvent than inorganic particles. In particular, acrylic resin particles are relatively easy to disperse in a solvent. The average particle size (D50) of particles 131 is greater than 0.5 μm, which is 5.0 μm. Particles 131 have insulating properties. Particles 131 preferably have heat resistance.

[0042] The binder 132 bonds the particles 131. The binder 132 has insulating properties.

[0043] The additive material 133 evenly disperses the particles 131 and the binder 132 , for example. The additive material 133 is not essential to the intermediate layer 130 .

[0044] The positive electrode 100 may include an insulating layer covering the positive electrode active material layer 120. The insulating layer has heat resistance. The insulating layer contains, for example, an inorganic material or an organic substance, and a binder. The inorganic material is, for example, aluminum oxide particles.

[0045] Negative electrode 200 Figure 3 As shown, it includes a negative electrode collector layer 210 and a negative electrode active material layer 220 .

[0046] The negative electrode collector layer 210 is, for example, configured in a long strip shape. That is, the negative electrode collector layer 210 is formed in a foil shape. At one end of the short side direction X of the negative electrode collector layer 210, a negative electrode collector portion 210a is provided along the long side direction Y. The negative electrode collector portion 210a of the negative electrode collector layer 210 is opposite to the positive electrode collector portion 110a of the positive electrode collector layer 110 in the short side direction X. The negative electrode collector layer 210 is, for example, formed of copper or a copper alloy. The thickness of the negative electrode collector layer 210 along the stacking direction Z is, for example, 10 μm. The thickness of the negative electrode collector layer 210 is, for example, selected within the range of 5 μm to 30 μm.

[0047] The negative electrode active material layer 220 is provided on the negative electrode collector layer 210. The negative electrode active material layer 220 is opposite to each other along the stacking direction Z in a state of being bonded to both surfaces of the negative electrode collector layer 210. The negative electrode active material layer 220 is longer in width along the short side direction X than the positive electrode active material layer 120. In a state where the negative electrode 200 is opposite to the positive electrode 100 via the separator 300, both ends of the short side direction X of the negative electrode active material layer 220 are located outside the short side direction X compared to both ends of the short side direction X of the positive electrode active material layer 120. The thickness of the negative electrode active material layer 220 along the stacking direction Z is, for example, 30 μm or 40 μm. The thickness of the negative electrode active material layer 220 is selected, for example, in the range of 10 μm to 200 μm.

[0048] The negative electrode active material layer 220 contains a negative electrode active material 221 and a negative electrode binder 222. The negative electrode active material layer 220 may contain a negative electrode conductive aid 223.

[0049] As the negative electrode active material 221, carbon is used, for example. Carbon is, for example, graphite, difficult-to-graphitize carbon (hard carbon), or easily-graphitize carbon (soft carbon). Graphite is, for example, natural graphite or artificial graphite. Natural graphite is, for example, flaky graphite, blocky graphite, and earthy graphite. The negative electrode active material 221 is formed into particles. The average particle size (D50) of the negative electrode active material 221 is, for example, 25 μm. The average particle size (D50) of the negative electrode active material 221 is, for example, selected within the range of 1 μm to 50 μm.

[0050] The negative electrode binder 222 binds the negative electrode active materials 221 together. As the negative electrode binder 222, for example, the same material as the positive electrode binder 122 is used.

[0051] The negative electrode conductive additive 223 improves the characteristics of the negative electrode 200. The negative electrode conductive additive 223 is mixed with the negative electrode active material 221 and improves the conductivity between the negative electrode current collecting layer 210 and the negative electrode active material 221. That is, the negative electrode conductive additive 223 ensures a conductive path between the negative electrode current collecting layer 210 and the negative electrode active material 221 in the negative electrode 200.

[0052] The negative electrode 200 may include an insulating layer covering the negative electrode active material layer 220. The insulating layer has heat resistance. The insulating layer contains, for example, an inorganic material or an organic substance, and a binder. The inorganic material is, for example, aluminum oxide particles.

[0053] Partition 300 Figure 3 As shown, the positive electrode 100 and the negative electrode 200 are insulated. In addition, the separator 300 retains the electrolyte (so-called electrolyte). The separator 300 is formed in a long strip shape. Compared with the negative electrode active material layer 220, the separator 300 has a longer width along the short side direction X. In a state where the positive electrode 100 and the negative electrode 200 are facing each other with the separator 300 in between, the two ends of the short side direction X of the positive electrode active material layer 120 are located within the range of the separator 300 along the short side direction X, and the two ends of the short side direction X of the negative electrode active material layer 220 are located within the range of the separator 300 along the short side direction X. The thickness of the separator 300 along the stacking direction Z is, for example, 20 μm. The thickness of the separator 300 is selected, for example, in the range of 5 μm to 60 μm.

[0054] The separator 300 is formed of a porous material. For example, polyethylene, polypropylene, polyester, cellulose, or polyamide is used as the porous material. The separator 300 may have a structure in which a plurality of different porous materials are stacked.

[0055] The separator 300 may have an insulating layer. The insulating layer has heat resistance. The insulating layer contains, for example, inorganic material or organic matter, and a binder. The non-polar material is, for example, aluminum oxide particles.

[0056] The electrolyte allows lithium ions to flow between the positive electrode 100 and the negative electrode 200. The electrolyte is also called an electrolytic solution.

[0057] The electrolyte contains an organic solvent and a lithium salt. The electrolyte may also contain additives.

[0058] As the organic solvent, for example, carbonate such as ethylene carbonate is used. As the lithium salt, for example, lithium hexafluorophosphate (LiPF6) is used. As the additive material, for example, lithium hexafluorophosphate (LiPF6) is used.

[0059] The outer casing 50 houses the charge / discharge body 10. Figure 1As shown, it includes a container 51, a cover 52, a liquid injection plug 53 and a cleavage valve 54. The container 51 is formed in a rectangular parallelepiped shape. The charge-discharge body 10 is accommodated in the container 51. The cover 52 is welded to the container 51. A liquid injection hole is provided on the cover 52. The liquid injection hole is a hole for injecting electrolyte (so-called electrolyte) into the interior of the battery 1. The liquid injection plug 53 is installed on the liquid injection hole of the cover 52. After the electrolyte is injected into the interior of the battery 1 through the liquid injection hole, the liquid injection plug 53 is inserted into the liquid injection hole and welded. The cleavage valve 54 is provided on the cover 52. The cleavage valve 54 is formed integrally with the cover 52. When the internal pressure of the battery 1 exceeds a specified value, the cleavage valve 54 cleaves toward the outside of the battery 1.

[0060] The external terminal 60 relays the input and output of power between the current collector provided inside the battery 1 and the electrical equipment provided outside the battery 1. For example, the electrical equipment is a relay and an inverter provided in a vehicle. In addition, the external terminal 60 provided in one battery 1 is electrically connected to the external terminal 60 provided in other batteries 1 via a bus bar or the like, and relays the input and output of power between one battery 1 and other batteries 1. The external terminal 60 is as follows: Figure 1 As shown, it includes a positive terminal 61 and a negative terminal 62. The positive terminal 61 is electrically connected to the positive electrode collecting portion 110a of the positive electrode collecting layer 110 via the positive electrode collecting plate. The positive terminal 61 is mounted on the cover 52 via the positive electrode insulating component. The negative terminal 62 is electrically connected to the negative electrode collecting portion 210a of the negative electrode collecting layer 210 via the negative electrode collecting plate. The negative terminal 62 is mounted on the cover 52 via the negative electrode insulating component.

[0061] (Method for Manufacturing Positive Electrode 100 According to First Embodiment)

[0062] For the method of manufacturing the positive electrode 100, refer to Figures 5 to 7 Provide explanation. Figure 5 It is a side view schematically showing a method for manufacturing the positive electrode 100 . Figure 6 It is a schematic representation of Figure 5 A top view of the coating state of the slurry of the positive electrode collector layer 110. Figure 7 It is a side view schematically showing a coating state of a positive electrode active material layer slurry 1100 and an intermediate layer slurry 1200 coated on a positive electrode current collecting layer 110 .

[0063] In the method for manufacturing the positive electrode 100, in the coating step, a positive electrode active material layer slurry 1100 and an intermediate layer slurry 1200 are coated. In the coating step, the intermediate layer slurry 1200 is coated on the positive electrode collector layer 110. In addition, in the coating step, the positive electrode active material layer 1100 is coated on the positive electrode collector layer 110 and the intermediate layer slurry 1200. In the coating step, the thickness of the intermediate layer slurry 1200 coated on the positive electrode collector layer 110 is set to be not less than 1 / 10 and not more than 1 / 2 of the thickness of the positive electrode active material layer slurry 1100 coated on the positive electrode collector layer 110. In the coating step, as Figure 7 As shown, the contact angle θ1 of the intermediate layer slurry 1200 with respect to the positive electrode collector layer 110 is set to be greater than 1° and less than 35°. The contact angle is a contact angle based on θ / 2 (A half-angle method). In this case, the contact angle θ2 of the positive electrode active material layer slurry 1100 with respect to the positive electrode collector layer 110 is less than θ1.

[0064] The positive electrode active material layer slurry 1100 used in the coating process contains a solvent in addition to the material constituting the positive electrode active material layer 120. The material constituting the positive electrode active material layer 120 includes a positive electrode active material 121, a positive electrode binder 122, and a positive electrode conductive aid 123. The solvent disperses the material contained in the positive electrode active material layer 120. As the solvent, for example, a solvent that is volatile at a temperature above room temperature is used. For example, the solvent is N-methyl-2-pyrrolidone (NMP, N-methylpyrrolidone).

[0065] The intermediate layer slurry 1200 used in the coating process contains a solvent in addition to the material constituting the intermediate layer 130. The solvent disperses the particles 131 and the binder 132 contained in the intermediate layer 130. As the solvent, for example, a solvent that is volatile at a temperature above room temperature is used. For example, the solvent is N-methyl-2-pyrrolidone (NMP).

[0066] The manufacturing device 1000 of the positive electrode 100 is as follows Figure 5 As shown, it includes a conveying section 1010 , a coating section 1020 , a drying section 1030 and a calendering section 1040 .

[0067] The transport unit 1010 Figure 5 As shown, the components constituting the positive electrode 100 are conveyed. The conveying unit 1010 includes conveying rollers 1011 .

[0068] The conveying unit 1010 conveys the positive electrode collector layer 110 wound on the first roller (not shown) to the coating unit 1020, the drying unit 1030 and the rolling unit 1040 via the conveying roller 1011 and the like. The conveying unit 1010 winds the positive electrode collector layer 110 after the positive electrode active material layer 120 and the intermediate layer 130 are joined on the second roller (not shown). When the second roller on which the positive electrode collector layer 110 is mounted rotates, the conveying roller 1011 and the first roller in contact with the positive electrode collector layer 110 also rotate to convey the positive electrode collector layer 110. The conveying direction H of the positive electrode collector layer 110 corresponds to the long side direction Y of the positive electrode collector layer 110.

[0069] The coating unit 1020 is as follows Figure 5 As shown, the slurry is coated on the positive electrode current collecting layer 110 etc. The coating unit 1020 includes a first coating head 1021 , a first liquid feeding pipe 1022 , a second coating head 1023 and a second liquid feeding pipe 1024 .

[0070] The first coating head 1021 is as Figure 5 and Figure 6 As shown, two are provided along the short side direction X which is orthogonal to the conveying direction H of the positive electrode collector layer 110, that is, the long side direction Y of the positive electrode collector layer 110. The two first coating heads 1021 are opposite to each other along the short side direction X of the positive electrode collector layer 110. An opening is formed in the first coating head 1021. The opening is connected to the first liquid feeding pipe 1022. For each first coating head 1021, the intermediate layer slurry 1200 is supplied from a container not shown in the figure via a pump not shown and the first liquid feeding pipe 1022. Each first coating head 1021 is opposite to the conveying roller 1011 across the positive electrode collector layer 110. Each first coating head 1021 coats the intermediate layer slurry 1200 on the positive electrode collector layer 110 while the positive electrode collector layer 110 is being conveyed. The intermediate layer slurry 1200 is coated on the positive electrode collector layer 110 in a direction opposite to the short side of the positive electrode collector layer 110 and along the length direction of the positive electrode collector layer 110 .

[0071] The second coating head 1023 is as follows Figure 5 and Figure 6As shown, it is arranged along the short side direction X of the positive electrode collector layer 110. The second coating head 1023 is arranged in parallel with the two first coating heads 1021 along the conveying direction H of the positive electrode collector layer 110. The second coating head 1023 is located on the downstream side of the conveying direction H of the positive electrode collector layer 110 relative to each first coating head 1021. In the second coating head 1023, a long strip opening is formed. The long strip opening is connected to the second liquid supply pipe 1024. For the second coating head 1023, the positive electrode active material layer slurry 1100 is supplied from a container not shown in the figure via a pump not shown in the figure and the second liquid supply pipe 1024. The second coating head 1023 is opposite to the conveying roller 1011 across the positive electrode collector layer 110. The second coating head 1023 coats the positive electrode active material layer slurry 1100 on the positive electrode current collecting layer 110 and the intermediate layer slurry 1200 while conveying the positive electrode current collecting layer 110 .

[0072] Drying section 1030 Figure 5 The drying unit 1030 is provided on the downstream side of the coating unit 1020 in the conveying direction H of the positive electrode current collecting layer 110 . The drying unit 1030 includes a dryer 1031 .

[0073] Dryer 1031 Figure 5 As shown, the dryer 1031 is arranged along the conveying direction H of the positive electrode collector layer 110, that is, the long side direction Y of the positive electrode collector layer 110. The dryer 1031 dries the positive electrode active material layer slurry 1100 and the intermediate layer slurry 1200 while the positive electrode collector layer 110 is being conveyed. The dryer 1031 has a plurality of heat sources along the conveying direction H of the positive electrode collector layer 110. The dryer 1031 uses a plurality of heat sources to dry the positive electrode active material layer slurry 1100 and the intermediate layer slurry 1200 based on a variety of conditions.

[0074] In the drying section 1030, the positive electrode active material layer slurry 1100 forms the positive electrode active material layer 120 due to the volatilization of the solvent. The NMP contained in the positive electrode active material layer slurry 1100 volatilizes, and the positive electrode active material layer slurry 1100 is dried. The thickness of the positive electrode active material layer slurry 1100 along the stacking direction Z decreases as it dries. The positive electrode active material layer 120 is bonded to the positive electrode collector layer 110. The intermediate layer slurry 1200 forms the intermediate layer 130 due to the volatilization of the solvent. The NMP contained in the intermediate layer slurry 1200 volatilizes, and the intermediate layer slurry 1200 is dried. The thickness of the intermediate layer slurry 1200 along the stacking direction Z decreases as it dries. The intermediate layer 130 is bonded to the positive electrode collector layer 110 and the positive electrode active material layer 120.

[0075] The calendering section 1040 is as follows Figure 5As shown, the positive electrode current collecting layer 110, the positive electrode active material layer 120, and the intermediate layer 130 in a bonded state are rolled. The rolling unit 1040 is provided downstream of the drying unit 1030 in the conveying direction H of the positive electrode current collecting layer 110. The rolling unit 1040 includes a rolling roll 1041 and a driven roll 1042.

[0076] Calendering roller 1041 Figure 5 As shown in FIG. 1 , the roller 1041 is arranged along the short side direction X of the positive electrode current collecting layer 110. The calendering roller 1041 faces the positive electrode active material layer 120 and the intermediate layer 130 in the positive electrode 100. The driven roller 1042 is as shown in FIG. Figure 5 As shown, the rollers 1042 are arranged along the short side direction X of the positive electrode current collecting layer 110. The driven roller 1042 faces the calendering roller 1041 across the positive electrode 100. The driven roller 1042 faces the positive electrode current collecting layer 110 in the positive electrode 100. The calendering unit 1040 defines the thickness of the positive electrode active material layer 120 by the interval between the calendering roller 1041 and the driven roller 1042.

[0077] In the method for manufacturing the positive electrode 100, reference is made to Figure 5 and Figure 6 The structure described above is a structure in which the positive electrode active material layer 120 and the intermediate layer 130 are bonded to one surface of the positive electrode current collecting layer 110. That is, Figure 5 and Figure 6 The method for manufacturing the positive electrode 100 shown in FIG. 1 is a method for manufacturing the positive electrode 100 by so-called single-sided coating. Figure 3 As shown, for example, a positive electrode active material layer 120 and an intermediate layer 130 are bonded to both sides of a positive electrode current collecting layer 110. That is, Figure 3 The positive electrode 100 shown in FIG. 1 is formed by so-called double-sided coating. Figure 5 and Figure 6 After the structure described above, the positive electrode active material layer 120 and the intermediate layer 130 are bonded to the other surface of the positive electrode active material layer 120 .

[0078] (Comparative Experimental Results of Positive Electrode 100 of First Embodiment and Positive Electrode of Comparative Example)

[0079] For the comparison test results of the positive electrode 100 of the first embodiment and the positive electrode of the comparative example, refer to Figure 8 Provide explanation. Figure 8 It is a graph showing the measurement results of the outer shapes of the positive electrode active material layer 120 of the positive electrode 100 of the first embodiment and the positive electrode active material layer of a comparative example.

[0080] Figure 8 The solid line graph shown is the measurement result of the outer shape of the positive electrode active material layer 120 of the positive electrode 100 according to the first embodiment. Figure 8The dashed line graph is a measurement result of the outer shape of the positive electrode active material layer of the positive electrode of the comparative example. The positive electrode 100 of the first embodiment and the positive electrode of the comparative example differ in manufacturing conditions only in whether the intermediate layer 130 is provided. The positive electrode 100 of the first embodiment is provided with the intermediate layer 130. The positive electrode of the comparative example is not provided with the intermediate layer 130. Figure 8 The vertical axis represents the layer thickness in the stacking direction Z of the positive electrode active material layer. Figure 8 The horizontal axis represents the distance in the short side direction X of the positive electrode active material layer.

[0081] like Figure 8 As shown, in the positive electrode active material layer 120 of the positive electrode 100 of the first embodiment, the end portion does not bulge in the stacking direction Z. That is, in the positive electrode active material layer 120 of the positive electrode 100 of the first embodiment, it is suppressed from being relatively thicker than other portions. On the other hand, in the positive electrode active material layer of the positive electrode of the comparative example, the end portion bulges in the stacking direction Z. That is, in the positive electrode active material layer of the positive electrode of the comparative example, it is relatively thicker than other portions. The bulge in the end portion of the positive electrode active material layer of the comparative example is 2% or more relative to the average layer thickness of the positive electrode active material layer.

[0082] (Effects of the Battery 1 and the Like Including the Positive Electrode 100 of the First Embodiment)

[0083] Effects of the battery 1 including the positive electrode 100 according to the first embodiment and the like will be described.

[0084] (1)(5)(9)(10) The positive electrode 100 (electrode) has an intermediate layer 130 (intermediate layer). The intermediate layer 130 is provided in the middle of the end 110b side of the positive electrode collector layer 110 (collector layer) and the end 120b of the positive electrode active material layer 120 (active material layer) along the stacking direction Z. The intermediate layer 130 is bonded to the positive electrode collector layer 110 and the positive electrode active material layer 120. According to such a structure, the end 120b of the positive electrode active material layer 120 (the positive electrode active material layer slurry 1100 when the positive electrode 100 is manufactured) bonded to the positive electrode collector layer 110 is separated from the positive electrode collector layer 110 during manufacturing, thereby being able to suppress its relative thickening. That is, the end 120b of the positive electrode active material layer 120 bonded to the positive electrode collector layer 110 is separated from the positive electrode collector layer 110 by the intermediate layer 130 (intermediate layer slurry 1200 when the positive electrode 100 is manufactured) during manufacturing, thereby being able to suppress detachment from the positive electrode collector layer 110. The detachment of the positive electrode active material layer slurry 1100 from the positive electrode collector layer 110 means that the affinity between the positive electrode active material layer slurry 1100 and the positive electrode collector layer 110 is relatively low. The ability to suppress detachment of the positive electrode active material layer slurry 1100 from the intermediate layer 130 means that the affinity between the positive electrode active material layer slurry 1100 and the intermediate layer slurry 1200 is relatively high. As a result, the positive electrode 100 can be obtained in which the end 120b of the positive electrode active material layer 120 is suppressed from being relatively thicker than other parts. In addition, according to such a structure, a battery 1 having a positive electrode 100 in which the end 120b of the positive electrode active material layer 120 is suppressed from becoming thicker can be obtained. That is, according to such a structure, the thickness of the positive electrode active material layer 120 can be made uniform.

[0085] (2) The intermediate layer 130 is bonded to the positive electrode current collecting layer 110 along the short side direction X intersecting the stacking direction Z, across the end 120b of the positive electrode active material layer 120. According to such a structure, the end 120b of the positive electrode active material layer 120 (the positive electrode active material layer slurry 1100 when the positive electrode 100 is manufactured) bonded to the positive electrode current collecting layer 110 can be sufficiently suppressed from being separated from the positive electrode current collecting layer 110 during manufacturing. The end 120b of the positive electrode active material layer 120 is most likely to be separated from the positive electrode current collecting layer 110 during manufacturing. That is, the end 120b of the positive electrode active material layer 120 bonded to the positive electrode current collecting layer 110 is sufficiently separated from the intermediate layer 130 during manufacturing, thereby being sufficiently suppressed from being separated from the positive electrode current collecting layer 110.

[0086] (3) In the intermediate layer 130, the first length L1 of the portion away from the positive electrode active material layer 120 along the short side direction X is longer than the second length L2 of the portion joined to the positive electrode active material layer 120 along the short side direction X. In the intermediate layer 130, the portion away from the positive electrode active material layer 120 is a portion joined only to the positive electrode collector layer 110. In the intermediate layer 130, the portion joined to the positive electrode active material layer 120 is a portion joined to both the positive electrode collector layer 110 and the positive electrode active material layer 120. According to such a structure, it is possible to sufficiently suppress the end 120b of the positive electrode active material layer 120 joined to the positive electrode collector layer 110 from being peeled off from the positive electrode collector layer 110.

[0087] (6) The thickness of the positive electrode active material layer 120 is greater than 10 μm and less than 60 μm. The thinner the positive electrode active material layer 120 (the positive electrode active material layer slurry 1100 when the positive electrode 100 is manufactured) is, the easier it is to be separated from the positive electrode collector layer 110 during manufacturing. The thickness of the positive electrode active material layer 120 is relatively thin when it is greater than 10 μm and less than 60 μm. However, because the intermediate layer 130 is present in the positive electrode 100, it is possible to suppress the end 120b of the positive electrode active material layer 120 bonded to the positive electrode collector layer 110 from being separated from the positive electrode collector layer 110 during manufacturing.

[0088] (7) In the intermediate layer 130, the thickness t1 in the region joined to the positive electrode active material layer 120 along the stacking direction Z is not less than 1 / 10 and not more than 1 / 2 of the thickness t2 of the positive electrode active material layer 120 along the stacking direction Z. According to such a structure, during manufacturing, the intermediate layer 130 (intermediate layer slurry 1200 when the positive electrode 100 is manufactured) can be used to suppress the end 120b of the positive electrode active material layer 120 (positive electrode active material layer slurry 1100 when the positive electrode 100 is manufactured) from being separated from the positive electrode collector layer 110, and at the same time, the thickness of the intermediate layer 130 that does not participate in the battery reaction can be suppressed.

[0089] (8) The intermediate layer 130 contains the particles 131 having insulating properties. With such a structure, the intermediate layer 130 can be formed using the particles 131 having high versatility.

[0090] (11) The intermediate layer 130 faces the negative electrode active material layer 220 of the negative electrode 200 via the separator 300 (insulator). With such a structure, the separator 300 can compensate for the insulation between the positive electrode 100 and the negative electrode 200 .

[0091] (12) In the method for manufacturing positive electrode 100, in the coating step, intermediate layer slurry 1200 is coated on positive electrode current collecting layer 110 of aluminum with a contact angle of 1° to 35°. With such a structure, separation of intermediate layer slurry 1200 from positive electrode current collecting layer 110 can be suppressed.

[0092] (13) In the coating step, the intermediate layer slurry 1200 is coated with the positive electrode current collecting layer 110 of aluminum so that the contact angle is set to 25° or less. With such a structure, it is possible to sufficiently suppress the intermediate layer slurry 1200 from being separated from the positive electrode current collecting layer 110 .

[0093] (14) In the coating process, the thickness of the intermediate layer slurry 1200 coated on the positive electrode collector layer 110 is set to be greater than 1 / 10 and less than 1 / 2 of the thickness of the positive electrode active material layer slurry 1100 coated on the positive electrode collector layer 110. According to such a structure, the intermediate layer slurry 1200 can suppress the end of the positive electrode active material layer slurry 1100 from being separated from the positive electrode collector layer 110, and at the same time, the thickness of the intermediate layer 130 that does not participate in the battery reaction can be suppressed.

[0094] (Structure of Positive Electrode 400 of Second Embodiment)

[0095] For the structure of the positive electrode 400 of the second embodiment, refer to Fig. 9 Provide explanation. Fig. 9 It is a cross-sectional view showing a charging and discharging body 20 of a battery according to a second embodiment.

[0096] The positive electrode 400 is different from the positive electrode 100 of the first embodiment in the arrangement of the intermediate layer 430 facing the positive electrode current collecting layer 110 and the positive electrode active material layer 120. Regarding the second embodiment, the same reference numerals are used for the same structures as those of the first embodiment, and description thereof is omitted.

[0097] The middle layer 430 is as follows Fig. 9 As shown in FIG. 1 , the third length L3 of the portion away from the positive electrode active material layer 120 along the short side direction X is shorter than the fourth length L4 of the portion joined to the positive electrode active material layer 120 along the short side direction X. The portion away from the positive electrode active material layer 120 is the portion where the intermediate layer 430 is joined only to the positive electrode collector layer 110. The portion joined to the positive electrode active material layer 120 is the portion where the intermediate layer 430 is joined to both the positive electrode collector layer 110 and the positive electrode active material layer 120. The intermediate layer 430 is as shown in FIG. Fig. 9 As shown, along the short side direction X, more positive electrode active material layers 120 and positive electrode collecting layers 110 are disposed in the region where the positive electrode active material layer 120 and positive electrode collecting layers 110 exist than in the region where the positive electrode active material layer 120 does not exist and only the positive electrode collecting layers 110 exist.

[0098] (Effects of the Positive Electrode 400 of the Second Embodiment)

[0099] The effects of the positive electrode 400 according to the second embodiment will be described.

[0100] (4) In the intermediate layer 430, the third length L3 of the portion away from the positive electrode active material layer 120 is shorter than the fourth length L4 of the portion joined to the positive electrode active material layer 120. According to such a structure, the end 120b of the positive electrode active material layer 120 (the positive electrode active material layer slurry 1100 when the positive electrode 100 is manufactured) joined to the positive electrode collector layer 110 can be sufficiently suppressed from being separated from the positive electrode collector layer 110 during manufacturing. That is, the end 120b of the positive electrode active material layer 120 joined to the positive electrode collector layer 110 is sufficiently separated from the intermediate layer 130 during manufacturing, thereby being sufficiently suppressed from being separated from the positive electrode collector layer 110.

[0101] (Structure of Positive Electrode 500 of Third Embodiment)

[0102] For the structure of the positive electrode 400 of the third embodiment, refer to Fig.10 Provide explanation. Fig.10 It is a cross-sectional view showing a charging and discharging body 30 of a battery according to a third embodiment.

[0103] The positive electrode 500 is different from the positive electrode 100 of the first embodiment in the arrangement of the intermediate layer 530 facing the positive electrode current collecting layer 110 and the positive electrode active material layer 120. Regarding the third embodiment, the same reference numerals are used for the same structures as those of the first embodiment, and description thereof is omitted.

[0104] The middle layer 530 is as follows Fig.10 As shown, the intermediate layer 530 is only provided between the positive electrode collector layer 110 and the positive electrode active material layer 120 along the stacking direction Z. The intermediate layer 530 is sandwiched between the positive electrode collector layer 110 and the positive electrode active material layer 120. The intermediate layer 530 is not provided in the region where the positive electrode active material layer 120 does not exist and only the positive electrode collector layer 110 exists along the short side direction X. The intermediate layer 530 is provided in the region where the positive electrode active material layer 120 and the positive electrode collector layer 110 exist along the short side direction X. The third embodiment is a structure in which the intermediate layer 130 is intentionally not provided in the region where the positive electrode active material layer 120 does not exist and only the positive electrode collector layer 110 exists. That is, the third embodiment includes a structure in which the intermediate layer 130 exists within the range of manufacturing error due to manufacturing error in the region where the positive electrode active material layer 120 does not exist and only the positive electrode collector layer 110 exists.

[0105] (Effects of the Positive Electrode 500 of the Third Embodiment)

[0106] Effects of the positive electrode 500 according to the third embodiment will be described.

[0107] (1) The middle layer 530 is as follows Fig.10As shown, it is only arranged between the positive electrode collector layer 110 and the positive electrode active material layer 120 along the stacking direction Z. According to such a structure, it is possible to fully suppress the end 120b of the positive electrode active material layer 120 (the positive electrode active material layer slurry 1100 when the positive electrode 100 is manufactured) bonded to the positive electrode collector layer 110 from being separated from the positive electrode collector layer 110 during manufacturing, while minimizing the intermediate layer 130 that does not participate in the battery reaction.

[0108] (Battery of Other Embodiments)

[0109] The battery of the present invention is not limited to the structure of the battery described in the embodiment, and can be appropriately configured based on the contents described in the claims.

[0110] The embodiment is described in detail or briefly for the purpose of explaining the present invention in an easy-to-understand manner, and does not need to have all the structures described, or may also have structures not shown. In addition, a part of the structure of the embodiment may be deleted, or replaced with the structure of other embodiments, or the structure of other embodiments may be combined.

[0111] In the electrode (positive electrode) of the present invention, the positive electrode active material is not limited to nickel (Ni), cobalt (Co) and manganese (Mn) based materials, but may be, for example, Fe (olivine iron) based materials.

[0112] In the electrode (negative electrode) of the present invention, the negative electrode active material is not limited to carbon-based materials, and the negative electrode active material of the present invention may also be silicon-based materials, for example.

[0113] The battery of the present invention is not limited to a structure in which the charge-discharge element is sealed by a container and a cover, but can be applied to a structure in which the charge-discharge element is sealed by a laminate film.

[0114] The battery of the present invention is not limited to a lithium ion battery, but can be applied to a nickel-hydrogen battery, for example.

[0115] The battery of the present invention is not limited to a secondary battery, but can be applied to a primary battery.

[0116] In the battery of the present invention, the charge-discharge body is not limited to a wound type in which the positive electrode, separator and negative electrode, which are respectively formed into long strips, are bundled and wound. As the charge-discharge body of the battery of the present invention, a stacked type in which the positive electrode, separator and negative electrode, which are respectively formed into rectangular shapes, are alternately stacked in multiple layers can be applied.

[0117] In the battery of the present invention, as a charge-discharge body, a stacked type can be applied in which a plurality of positive electrodes and a plurality of negative electrodes formed into relatively short shapes are alternately arranged opposite to each other through a separator for a single separator formed into a long strip. The charge-discharge body of such a structure is stacked by folding the separator so that the positive electrode and the negative electrode face each other through the separator.

[0118] In the battery of the present invention, the charge and discharge body is not limited to a rectangular parallelepiped type, and a cylindrical or columnar type can be applied as the charge and discharge body of the battery of the present invention.

[0119] In the battery of the present invention, the charge and discharge body is not limited to a structure in which a separator having insulating properties is provided between the positive electrode and the negative electrode. The battery of the present invention can be applied to a structure in which a separator is not provided but an insulating layer is provided in at least one of the positive electrode and the negative electrode. Such a structure is equivalent to a so-called separator-free structure.

[0120] In the battery of the present invention, in addition to the structure in which the separator 300 having insulating properties is provided between the positive electrode 100 and the negative electrode 200, the charging and discharging body can also be applied to a structure in which an insulating layer is provided on the positive electrode 100 or an insulating layer is provided on the negative electrode 200.

[0121] In the battery of the present invention, the charging and discharging body is not limited to a structure in which only one charging and discharging body is provided. The battery of the present invention can be applied to a structure in which two or more charging and discharging bodies are provided.

[0122] The electrode (positive electrode, negative electrode) of the present invention is not limited to the structure in which the end of the collector layer is joined to the collector plate. The battery electrode of the present invention can be applied to the type in which an electrode tab protruding from the edge of the collector layer is joined to the collector plate.

[0123] The electrode (positive electrode, negative electrode) of the present invention is not limited to a structure in which an active material layer is bonded to both surfaces of a current collecting layer, but can be applied to a structure in which an active material layer is bonded to only one surface of a current collecting layer.

[0124] The manufacturing method of the electrode (positive electrode, negative electrode) of the present invention is not limited to the structure in which the active material layer and the intermediate layer are formed by simultaneously applying the active material layer slurry and the intermediate layer slurry and drying them. The manufacturing method of the electrode (positive electrode, negative electrode) of the present invention can be applied to the structure in which the intermediate layer slurry is first applied to the collector layer and dried to form the intermediate layer. In the case of such a structure, the active material layer slurry is then applied to the collector layer and the intermediate layer and dried to form the active material layer.

[0125] The method for manufacturing an electrode (positive electrode, negative electrode) of the present invention is not limited to a structure in which the first coating head and the second coating head are independently provided. The method for manufacturing an electrode (positive electrode, negative electrode) of the present invention can be applied to a structure in which the first coating head and the second coating head are integrated.

[0126] Explanation of symbols

[0127] 1 battery,

[0128] 10, 20, 30 charge and discharge,

[0129] 50 outer body,

[0130] 51 containers,

[0131] 52 Cover,

[0132] 53 Filling plug,

[0133] 54 Cracking valve,

[0134] 60 external terminals,

[0135] 61 positive terminal,

[0136] 62 Negative terminal,

[0137] 100, 400, 500 positive electrode (electrode),

[0138] 110 positive electrode collector layer (collector layer),

[0139] 110a: positive electrode current collecting portion,

[0140] 110b end,

[0141] 120 positive electrode active material layer (active material layer),

[0142] 120b end,

[0143] 121 positive electrode active material (active material),

[0144] 122 positive electrode binder,

[0145] 123 Positive electrode conductive additive,

[0146] 130, 430, 530 middle layer,

[0147] 131 particles,

[0148] 132 Binder,

[0149] 133 Added materials (additional parts),

[0150] 200 negative electrode,

[0151] 210 negative electrode current collecting layer,

[0152] 210a negative electrode current collecting portion,

[0153] 220 negative electrode active material layer,

[0154] 221 Negative electrode active material,

[0155] 222 negative electrode binder,

[0156] 223 Negative electrode conductive additive,

[0157] 300 separator (insulator),

[0158] 1000 Manufacturing Devices,

[0159] 1010 Transportation Department,

[0160] 1011 Transport roller,

[0161] 1020 Coating Department,

[0162] 1021 First coating head,

[0163] 1022 first liquid delivery pipe,

[0164] 1023 Second coating head,

[0165] 1024 Second liquid delivery pipe,

[0166] 1030 Drying Department

[0167] 1031 Dryer,

[0168] 1040 Calendering Department,

[0169] 1041 calender roller,

[0170] 1042 driven roller,

[0171] 1100 positive electrode active material layer slurry,

[0172] 1200 Insulation paste,

[0173] t1 (thickness of the intermediate layer 130 along the stacking direction Z),

[0174] t2 (thickness of the positive electrode active material layer 120 along the stacking direction Z),

[0175] L1 (a first length of a portion of the intermediate layer 130 away from the positive electrode active material layer 120 along the short side direction X),

[0176] L2 (a second length along the short side direction X of the portion of the intermediate layer 130 that is bonded to the positive electrode active material layer 120),

[0177] L3 (a third length of the portion of the intermediate layer 130 away from the positive electrode active material layer 120 along the short side direction X),

[0178] L4 (a fourth length along the short side direction X of the portion of the intermediate layer 130 that is bonded to the positive electrode active material layer 120),

[0179] θ1 (contact angle of the intermediate layer slurry 1200 for the positive electrode current collector layer 110),

[0180] θ2 (contact angle of the positive electrode active material layer slurry 1100 with respect to the positive electrode current collector layer 110),

[0181] X is the short side direction (of the positive electrode 100, the negative electrode 200, and the separator 300),

[0182] Y (the long side direction of the positive electrode 100, the negative electrode 200, and the separator 300),

[0183] Z (the stacking direction of the positive electrode 100, the negative electrode 200, and the separator 300),

[0184] H: conveying direction (longitudinal direction Y) of (positive electrode 100 , negative electrode 200 , and separator 300 ).

Claims

1. An electrode, comprising: Current collecting layer; an active material layer, which contains an active material and is laminated and bonded to the current collecting layer; and The intermediate layer is provided between one end of the current collecting layer and the end of the active material layer in the stacking direction and is bonded to the current collecting layer and the active material layer.

2. The electrode according to claim 1, wherein The intermediate layer is bonded to the current collecting layer across the end of the active material layer in a direction intersecting the stacking direction.

3. The electrode according to claim 2, wherein A first length of a portion of the intermediate layer separated from the active material layer along the intersecting direction is longer than a second length of a portion of the intermediate layer bonded to the active material layer along the intersecting direction.

4. The electrode according to claim 2, wherein A third length of a portion of the intermediate layer separated from the active material layer along the intersecting direction is shorter than a fourth length of a portion of the intermediate layer bonded to the active material layer along the intersecting direction.

5. The electrode according to claim 1, wherein The current collecting layer is a positive electrode current collecting layer, The active material layer is a positive electrode active material layer containing a positive electrode active material.

6. The electrode according to claim 1, wherein The active material layer has a thickness of 10 μm or more and 60 μm or less.

7. The electrode according to claim 1, wherein A thickness of the intermediate layer in a region bonded to the active material layer along the stacking direction is not less than 1 / 10 and not more than 1 / 2 of a thickness of the active material layer along the stacking direction.

8. The electrode according to claim 1, wherein The intermediate layer contains particles having insulating properties.

9. A battery comprising a positive electrode, a negative electrode and an insulator for insulating the positive electrode from the negative electrode, At least one of the positive electrode and the negative electrode has: Current collecting layer; an active material layer containing an active material and laminated and bonded to the current collecting layer; and The intermediate layer is provided between one end of the current collecting layer and the end of the active material layer in the stacking direction and is bonded to the current collecting layer and the active material layer.

10. The battery according to claim 9, which is applied to the positive electrode.

11. The battery according to claim 10, wherein The intermediate layer of the positive electrode faces the negative electrode active material layer of the negative electrode via the insulator.

12. A method for manufacturing a positive electrode, The positive electrode comprises: Positive electrode current collecting layer; A positive electrode active material layer, which contains a positive electrode active material and is laminated and bonded to the positive electrode current collecting layer; and an intermediate layer, which is provided between one end of the positive electrode collector layer and the end of the positive electrode active material layer in the stacking direction and is bonded to the positive electrode collector layer and the positive electrode active material layer, The method for manufacturing the positive electrode uses: The positive electrode current collecting layer contains aluminum; An intermediate layer slurry containing particles and a volatile solvent and constituting the intermediate layer after being coated on the positive electrode current collecting layer; and a positive electrode active material layer slurry containing the positive electrode active material and the volatile solvent and constituting the positive electrode active material layer after being coated on the positive electrode collector layer and the intermediate layer slurry, The positive electrode manufacturing method includes a coating step of coating the intermediate layer slurry and the positive electrode active material layer slurry. In the coating process, The intermediate layer slurry is applied to the positive electrode current collecting layer with a contact angle set to be greater than 1° and less than 35°, The positive electrode active material layer slurry is applied to the positive electrode collector layer and the intermediate layer slurry.

13. The method for manufacturing a positive electrode according to claim 12, wherein: In the coating step, the intermediate layer slurry is coated on the positive electrode current collecting layer with a contact angle set to 25° or less.

14. The method for manufacturing a positive electrode according to claim 12, wherein: In the coating step, the thickness of the intermediate layer slurry coated on the positive electrode current collecting layer is set to be 1 / 10 or more and 1 / 2 or less of the thickness of the positive electrode active material layer slurry coated on the positive electrode current collecting layer.

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