Electrode, battery, and method for manufacturing electrode

Abstract

The invention provides an electrode, a battery and a manufacturing method of the 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)) that is laminated and bonded to the collector layer and contains an active material (positive electrode active material (121)); and an end insulating layer (130) that is laminated and bonded from the end (110b) side of the collector layer to the side (120a) of the active material layer (positive electrode active material layer (120)) and contains particles (131) and a binder (132). The proportion of the particles (131) in the end insulating layer (130) is 55% or more and 99.5% or less. The proportion of the particles (131) and the binder (132) in the end insulating layer (130) is 55.5% or more and 99% or less. The thickness of the end insulating layer (130) in the lamination direction (Z) is 1 / 20 to 1 / 2 of the thickness of the active material layer (positive electrode active material layer (120)) in the lamination direction (Z).

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 related to an electrode in which an active material layer and an insulating layer are joined at an end of a current collecting layer (for example, refer to 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] It is required to suppress the end insulating layer bonded to the active material layer from being separated from the current collecting layer.

[0008] Means for solving problems

[0009] The electrode of the present invention comprises a current collecting layer, an active material layer and an end insulating layer. The active material layer contains an active material and is laminated and bonded to the current collecting layer. The end insulating layer contains particles and a binder and is laminated from one end side of the current collecting layer to the side of the active material layer and bonded to them. The proportion of the particles in the end insulating layer is greater than 55% and less than 99.5%. The proportion of the particles and the binder in the end insulating layer is greater than 55.5% and less than 99%. The thickness of the end insulating layer in the stacking direction is greater than 1 / 20 and less than 1 / 2 of the thickness of the active material layer in the stacking direction.

[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 electrode of the present invention is the manufacturing method of the electrode. In the manufacturing method of the electrode, an end insulating layer slurry containing the particles, the binder and a volatile solvent is used, which is applied to the collector layer and the active material layer to form the end insulating layer. The manufacturing method of the electrode includes a coating step of coating the end insulating layer slurry on the collector layer and the active material layer. The shrinkage rate of the end insulating layer slurry accompanying drying is greater than 1% and less than 40%.

[0012] Effects of the Invention

[0013] According to the present invention, it is possible to obtain an electrode in which separation of the end insulating layer from the current collecting layer is suppressed, 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 7 It is a cross-sectional view showing a charging and discharging body 20 of a battery according to a second embodiment.

[0021] Figure 8 It is schematically indicated Figure 7 1 is a side view showing a method for manufacturing a positive electrode 400 included in the charge / discharge body 20.

[0022] Fig. 9 It is a schematic representation of Figure 8 A top view of the coating state of the slurry of the positive electrode collector layer 110.

[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) Figure 3 As shown, the positive electrode collector layer 110 , the positive electrode active material layer 120 and the end insulating layer 130 are included.

[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 end insulating layer 130 is as follows Figure 4 As shown, the positive electrode current collecting layer 110 is stacked from the end 110b side to the side 120a of the positive electrode active material layer 120 and bonded thereto (stacked and bonded from the end 110b side of the positive electrode current collecting layer 110 to the side 120a of the positive electrode active material layer 120).

[0039] The thickness t1 of the end insulating layer 130 along the stacking direction Z is 1 / 20 or more and 1 / 2 or less of the thickness t2 of the positive electrode active material layer 120 along the stacking direction Z. The thickness t1 of the end insulating layer 130 along the stacking direction Z may be set to 1 / 10 or more and 1 / 5 or less of the thickness t2 of the positive electrode active material layer 120 along the stacking direction Z. The thickness t1 of the end insulating layer 130 along the stacking direction Z is 1 μm or more and 15 μm or less at the portion bonded to the positive electrode collector layer 110 or the portion bonded to the positive electrode active material layer 120. The thickness t1 of the end insulating layer 130 along the stacking direction Z may be 2 μm or more and 5 μm or less.

[0040] In the end insulating layer 130, as 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, organic particles or inorganic particles. Organic particles are, for example, acrylic resin particles. 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 and is 5.0 μm. Particles 131 are insulating. Particles 131 are preferably heat-resistant. The proportion of particles 131 in the end insulating layer 130 is greater than 55% and less than 99.5%.

[0042] The binder 132 bonds the particles 131. The binder 132 has insulating properties. The particles 131 and the binder 132 account for 55.5% or more and 99% or less of the end insulating layer 130. That is, the binder 132 accounts for 0.5% or more and 45% or less of the end insulating layer 130.

[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 end insulating 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 wider 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 1 As 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 Figure 5 and Figure 6 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.

[0063] In the method for manufacturing the positive electrode 100 , in the coating step, the positive electrode active material layer slurry 1100 and the end insulating layer slurry 1200 are coated on the positive electrode current collecting layer 110 .

[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 end insulating layer slurry 1200 used in the coating process contains a solvent in addition to the material constituting the end insulating layer 130. The solvent disperses the particles 131 and the binder 132 contained in the end insulating 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). The shrinkage rate of the end insulating layer slurry 1200 accompanying drying is greater than 1% and less than 40%.

[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 end insulating 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, and the positive electrode collector layer 110 is conveyed at the same time. The conveying direction H of the positive electrode collector layer 110 is equivalent to the long side direction Y of the positive electrode collector layer 110.

[0069] The coating unit 1020 is as follows Figure 5As 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 conveying direction H of the positive electrode collector layer 110, that is, the short side direction X orthogonal to 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 end insulating 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 end insulating layer slurry 1200 on the positive electrode collector layer 110 while the positive electrode collector layer 110 is being conveyed. The end insulating 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 long side of the positive electrode collector layer 110 .

[0071] The second coating head 1023 is as follows Figure 5 and Figure 6 As 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 end insulating 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 5As 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 end insulating 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 end insulating 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 end insulating layer slurry 1200 forms the end insulating layer 130 due to the volatilization of the solvent. The NMP contained in the end insulating layer slurry 1200 volatilizes, and the end insulating layer slurry 1200 is dried. The thickness of the end insulating layer slurry 1200 along the stacking direction Z decreases as it dries. The end insulating layer 130 is bonded to the side portion 120a of the positive electrode active material layer 120.

[0075] The calendering section 1040 is as follows Figure 5 As shown, the positive electrode current collecting layer 110, the positive electrode active material layer 120 and the end insulating 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 end insulating 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 end insulating layer 130 are bonded to one side of the positive electrode current collecting layer 110. That is, Figure 5 and Figure 6The 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 end insulating 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 end insulating 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] The results of a comparative experiment on the positive electrode 100 of the first embodiment and the positive electrode of the comparative example will be described with reference to Table 1. Table 1 shows the results of an experiment on the peeling of the end insulating layer from the positive electrode current collecting layer.

[0080] [Table 1]

[0081]

[0082] The end insulating layer of Condition 1 corresponds to the end insulating layer 130 of the positive electrode 100 of the embodiment (first embodiment). On the other hand, the end insulating layer of Conditions 2, 3, and 4 corresponds to the end insulating layer of the positive electrode of the comparative example.

[0083] In condition 1, in the end insulating layer 130, the ratio of the particles 131 was set to 69%, and the ratio of the binder 132 was set to 31%. In condition 1, the thickness of the end insulating layer 130 in the stacking direction Z was set to 10 μm.

[0084] In condition 2, the ratio of the insulator in the end insulating layer was set to 69% and the ratio of the adhesive was set to 31% similarly to condition 1. In condition 2, unlike condition 1, the thickness of the end insulating layer in the stacking direction Z was set to 18 μm.

[0085] In condition 3, the conditions are reversed compared to condition 1, and the ratio of the insulator in the end insulating layer is set to 31%, and the ratio of the adhesive is set to 69%. In condition 3, similarly to condition 1, the thickness of the end insulating layer in the stacking direction Z is set to 10 μm.

[0086] In condition 4, the ratio of the insulator in the end insulating layer was set to 31% and the ratio of the adhesive was set to 69% similarly to condition 1. In condition 3, similarly to condition 2, the thickness of the end insulating layer in the stacking direction Z was set to 18 μm.

[0087] The end insulating layer 130 of condition 1 sufficiently suppressed reverse bending with respect to the positive electrode current collecting layer 110. That is, the end insulating layer 130 of condition 1 sufficiently suppressed peeling from the positive electrode current collecting layer 110. Therefore, the end insulating layer 130 of condition 1 was evaluated as ○ (sufficiently suppressed peeling) for suppression of peeling.

[0088] The end insulating layer of condition 2 suppressed reverse bending to the positive electrode collector layer to a certain extent. That is, the end insulating layer of condition 2 suppressed peeling from the positive electrode collector layer to a certain extent. Therefore, the end insulating layer of condition 2 was evaluated as △ (suppressing peeling to a certain extent) for suppressing peeling.

[0089] The end insulating layer of condition 3 was greatly bent in the opposite direction to the positive electrode current collecting layer. That is, the end insulating layer of condition 3 was peeled off from the positive electrode current collecting layer. Therefore, the end insulating layer of condition 3 was evaluated as × (peeling could not be suppressed) for the suppression of peeling.

[0090] The end insulating layer of condition 4 was more bent in the opposite direction to the positive electrode current collecting layer than the end insulating layer of condition 3. That is, the end insulating layer of condition 4 was peeled off from the positive electrode current collecting layer in the same manner as the end insulating layer of condition 3. Therefore, the end insulating layer of condition 4 was evaluated as × (peeling could not be suppressed) for the suppression of peeling.

[0091] In condition 1, the shrinkage of the end insulating layer slurry 1200 with a relatively small amount of binder 132 is relatively suppressed when the solvent is dried to form the end insulating layer 130. As a result, the peeling of the end insulating layer 130 from the positive electrode collector layer 110 is suppressed. The shrinkage of the end insulating layer slurry 1200 with a relatively thin layer thickness is relatively suppressed when the solvent is dried to form the end insulating layer 130. As a result, the peeling of the end insulating layer 130 from the positive electrode collector layer 110 is suppressed.

[0092] (Effects of the Battery 1 and Others Including the Positive Electrode 100 of the First Embodiment)

[0093] Effects of the battery 1 and the like including the positive electrode 100 according to the first embodiment will be described.

[0094] (1)(7)(8) The positive electrode 100 (electrode) has an end insulating layer 130. The end insulating layer 130 is laminated from the end 110b side of the positive electrode current collecting layer 110 (current collecting layer) to the side 120a of the positive electrode active material layer 120 (active material layer) and is bonded to them. The end insulating layer 130 contains particles 131 and a binder 132. The ratio of the particles 131 to the end insulating layer 130 is greater than 55% and less than 99.5%. The ratio of the particles 131 and the binder 132 to the end insulating layer 130 is greater than 55.5% and less than 99%. In this case, the binder 132 is greater than 0.5% and less than 45%. The thickness of the end insulating layer 130 along the stacking direction Z is greater than 1 / 20 and less than 1 / 2 of the thickness of the positive electrode active material layer 120 along the stacking direction Z. According to such a structure, the reverse bending of the end insulating layer 130 with respect to the positive electrode current collecting layer 110 can be suppressed. That is, according to such a structure, it is possible to suppress the end insulating layer 130 from peeling off from the positive electrode collector layer 110. As a result, it is possible to obtain the positive electrode 100 in which the end insulating layer 130 is suppressed from peeling off from the positive electrode collector layer 110. In addition, according to such a structure, it is possible to obtain the battery 1 having the positive electrode 100 in which the end insulating layer 130 is suppressed from peeling off from the positive electrode collector layer 110.

[0095] (2) The thickness of the end insulating layer 130 along the stacking direction Z is not less than 1 / 10 and not more than 1 / 5 of the thickness of the positive electrode active material layer 120 along the stacking direction Z. With such a structure, the end insulating layer 130 is also sufficiently bonded to the positive electrode active material layer 120 , thereby being sufficiently prevented from being peeled off from the positive electrode current collecting layer 110 .

[0096] (3) The thickness of the end insulating layer 130 along the stacking direction Z is 1 μm or more and 15 μm or less at the portion bonded to the positive electrode collector layer 110 or the portion bonded to the positive electrode active material layer 120. With such a structure, the end insulating layer 130 is also sufficiently bonded to the positive electrode active material layer 120, thereby being sufficiently prevented from peeling off from the positive electrode collector layer 110.

[0097] (4) The thickness of the end insulating layer 130 in the stacking direction Z is 2 μm or more and 5 μm or less. With such a structure, the end insulating layer 130 is also sufficiently bonded to the positive electrode active material layer 120 , thereby being sufficiently prevented from being separated from the positive electrode current collecting layer 110 .

[0098] (9) In the method for manufacturing the positive electrode 100, in the coating step, the shrinkage rate of the end insulating layer slurry 1200 accompanying drying is 1% or more and 40% or less. With such a structure, the end insulating layer 130 can be sufficiently suppressed from bending in the opposite direction to the positive electrode collector layer 110 due to shrinkage during drying. That is, with such a structure, it is possible to sufficiently suppress the end insulating layer 130 from peeling off from the positive electrode collector layer 110.

[0099] (Structure of Positive Electrode 400 of Second Embodiment)

[0100] For the structure of the positive electrode 400 of the second embodiment, refer to Figure 7 Provide explanation. Figure 7 It is a cross-sectional view showing a charging and discharging body 20 of a battery according to a second embodiment.

[0101] The positive electrode 400 is different from the positive electrode 100 of the first embodiment in that an end insulating layer 430 is also provided on the end 120b of the positive electrode active material layer 120. Regarding the second embodiment, the same components as those of the first embodiment are denoted by the same reference numerals and their description is omitted.

[0102] The end insulating layer 430 is stacked from the end 110b of the positive electrode collector layer 110 and passes through the side 120a of the positive electrode active material layer 120 (the end insulating layer 430 is stacked and bonded from the end 110b of the positive electrode collector layer 110 through the side 120a of the positive electrode active material layer 120 to the end 120b of the positive electrode active material layer 120), and is bonded to the end 120b of the positive electrode active material layer 120. The end insulating layer 430 is bonded to both the positive electrode collector layer 110 and the positive electrode active material layer 120 along the short side direction X with the side 120a of the positive electrode active material layer 120 as the boundary. That is, the end insulating layer 430 partially overlaps with the positive electrode active material layer 120 along the stacking direction Z.

[0103] (Method for Manufacturing Positive Electrode 400 According to Second Embodiment)

[0104] For the method of manufacturing the positive electrode 400, refer to Figure 8 and Fig. 9 Only the structure that is different from the manufacturing method of the positive electrode 100 will be described. Figure 8 It is schematically indicated Figure 7 1 is a side view showing a method for manufacturing a positive electrode 400 included in the charge / discharge body 20. Fig. 9 It is a schematic representation of Figure 8 A top view of the coating state of the slurry of the positive electrode collector layer 110.

[0105] The manufacturing device 2000 of the positive electrode 400 is as follows Figure 8 As shown, it includes a conveying section 1010 , a coating section 2020 , a drying section 1030 and a calendering section 1040 .

[0106] Coating Department 2020 Figure 8 As shown, the slurry is coated on the positive electrode current collecting layer 110 etc. The coating unit 2020 includes a first coating head 2021 , a first liquid feeding pipe 1022 , a second coating head 2023 and a second liquid feeding pipe 1024 .

[0107] First coating head 2021 Figure 8 and Fig. 9 As shown, it is arranged 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. An elongated opening is formed in the first coating head 2021. The elongated opening is connected to the first liquid feeding pipe 1022. For the first coating head 2021, the positive electrode active material layer slurry 1100 is supplied from a container not shown in the figure via a pump not shown and the first liquid feeding pipe 1022. The first coating head 2021 is opposite to the conveying roller 1011 across the positive electrode collector layer 110. The first coating head 2021 coats the positive electrode active material layer slurry 1100 on the positive electrode collector layer 110 while the positive electrode collector layer 110 is being conveyed.

[0108] The second coating head 2023 Figure 8 and Fig. 9 As shown, two are provided along the short side direction X of the positive electrode collector layer 110. The two second coating heads 2023 are opposite to each other along the short side direction X of the positive electrode collector layer 110. The second coating head 2023 is arranged in parallel with the first coating head 2021 along the conveying direction H of the positive electrode collector layer 110. The second coating head 2023 is located on the downstream side of the conveying direction H of the positive electrode collector layer 110 relative to the first coating head 2021. An opening is formed in the second coating head 2023. The opening is connected to the second liquid supply pipe 1024. For each second coating head 2023, the end insulating layer slurry 1200 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. Each second coating head 2023 is opposite to the conveying pipe 1011 across the positive electrode collector layer 110. Each second coating head 2023 applies the end insulating layer slurry 1200 to the ends of the positive electrode collector layer 110 and the positive electrode active material layer slurry 1100 while conveying the positive electrode collector layer 110. The end insulating layer slurry 1200 is applied to the positive electrode collector layer 110 in a direction opposite to the short side of the positive electrode collector layer 110 and along the long side of the positive electrode collector layer 110. The end insulating layer slurry 1200 is applied in a manner of covering both ends of the short side of the positive electrode active material layer slurry 1100.

[0109] (Effects of Battery Including Positive Electrode 400 of Second Embodiment)

[0110] The effects of the battery including the positive electrode 400 of the second embodiment will be described.

[0111] (5) The end insulating layer 430 is stacked from the end 110b side of the positive electrode collector layer 110 and passes through the side 120a of the positive electrode active material layer 120 to the end 120b of the positive electrode active material layer 120 to be bonded to them. According to such a structure, the positive electrode active material layer 120 is sufficiently bonded to the end insulating layer 130, thereby being sufficiently suppressed from peeling off from the positive electrode collector layer 110. In addition, according to such a structure, the end insulating layer 130 is sufficiently bonded to the positive electrode active material layer 120, thereby being sufficiently suppressed from peeling off from the positive electrode collector layer 110.

[0112] (Structure of Positive Electrode 500 of Third Embodiment)

[0113] For the structure of the positive electrode 500 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.

[0114] The positive electrode 500 is different from the positive electrode 100 of the first embodiment in that an end insulating layer 530 is also provided between the positive electrode current collecting layer 110 and the positive electrode active material layer 120 along the stacking direction Z. 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.

[0115] The end insulating layer 530 is stacked from the end 110b side of the positive electrode collector layer 110 to between the positive electrode active material layer 120 and the positive electrode collector layer 110 and joined to them. The end insulating layer 530 is joined to both the positive electrode collector layer 110 and the positive electrode active material layer 120 along the short side direction X with the side portion 120a of the positive electrode active material layer 120 as the boundary. The end insulating layer 530 is also provided between the positive electrode collector layer 110 and the positive electrode active material layer 120. That is, the end insulating layer 530 and the positive electrode active material layer 120 partially overlap along the stacking direction Z.

[0116] (Effects of Battery Including Positive Electrode 500 of Third Embodiment)

[0117] The effects of the battery including the positive electrode 500 of the third embodiment will be described.

[0118] (6) The end insulating layer 530 is stacked between the positive electrode active material layer 120 and the positive electrode collector layer 110 from the end 110b side of the positive electrode collector layer 110 and bonded to them. That is, the positive electrode active material layer 120 is fully bonded to the positive electrode collector layer 110 along the stacking direction Z via the end insulating layer 130 having a higher affinity than the positive electrode collector layer 110. According to such a structure, the positive electrode active material layer 120 is fully bonded to the end insulating layer 130, thereby being able to fully suppress its peeling from the positive electrode collector layer 110. In addition, according to such a structure, the end insulating layer 130 is sandwiched between the positive electrode active material layer 120 and the positive electrode collector layer 110 and is fully bonded, thereby being able to fully suppress its peeling from the positive electrode collector layer 110.

[0119] (Battery of Other Embodiments)

[0120] 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.

[0121] 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.

[0122] 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.

[0123] 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.

[0124] 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.

[0125] 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.

[0126] The battery of the present invention is not limited to a secondary battery, but can be applied to a primary battery.

[0127] 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.

[0128] 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.

[0129] 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.

[0130] 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.

[0131] 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.

[0132] 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.

[0133] 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.

[0134] 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.

[0135] 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 end insulating layer are formed by simultaneously applying the active material layer slurry and the end insulating 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 active material layer slurry is first applied to the collector layer and dried to form the active material layer. In the case of such a structure, the end insulating layer slurry is then applied to the collector layer and dried to form the end insulating layer. In addition, the manufacturing method of the electrode (positive electrode, negative electrode) of the present invention can be applied to the structure in which the end insulating layer slurry is first applied to the collector layer and dried to form the end insulating layer. In the case of such a structure, the active material layer slurry is then applied to the collector layer and dried to form the active material layer.

[0136] 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.

[0137] Explanation of symbols

[0138] 1 battery,

[0139] 10, 20, 30 charge and discharge,

[0140] 50 outer body,

[0141] 51 containers,

[0142] 52 Cover,

[0143] 53 Filling plug,

[0144] 54 Cracking valve,

[0145] 60 external terminals,

[0146] 61 positive terminal,

[0147] 62 Negative terminal,

[0148] 100, 400, 500 positive electrode (electrode),

[0149] 110 positive electrode collector layer (collector layer),

[0150] 110a: positive electrode current collecting portion,

[0151] 110b end,

[0152] 120 positive electrode active material layer (active material layer),

[0153] 120a side,

[0154] 120b end,

[0155] 121 positive electrode active material (active material),

[0156] 122 positive electrode binder,

[0157] 123 Positive electrode conductive additive,

[0158] 130, 430, 530 end insulation layer,

[0159] 131 particles,

[0160] 132 Binder,

[0161] 133 Added materials (additional parts),

[0162] 200 negative electrode,

[0163] 210 negative electrode current collecting layer,

[0164] 210a negative electrode current collecting portion,

[0165] 220 negative electrode active material layer,

[0166] 221 Negative electrode active material,

[0167] 222 negative electrode binder,

[0168] 223 Negative electrode conductive additive,

[0169] 300 separator (insulator),

[0170] 1000, 2000 manufacturing equipment,

[0171] 1010 Transportation Department,

[0172] 1011 Transport roller,

[0173] 1020, 2020 Coating Department

[0174] 1021, 2021 first coating head,

[0175] 1022 a first liquid delivery pipe,

[0176] 1023, 2023 second coating head,

[0177] 1024 Second liquid delivery pipe,

[0178] 1030 Drying Department

[0179] 1031 Dryer,

[0180] 1040 Calendering Department,

[0181] 1041 calender roller,

[0182] 1042 driven roller,

[0183] 1100 positive electrode active material layer slurry,

[0184] 1200 Insulation paste,

[0185] t1 Thickness of the end insulating layer 130 along the stacking direction Z

[0186] t2 Thickness of the positive electrode active material layer 120 along the stacking direction Z

[0187] X is the short side direction (of the positive electrode 100, the negative electrode 200, and the separator 300),

[0188] Y (the long side direction of the positive electrode 100, the negative electrode 200, and the separator 300),

[0189] Z (the stacking direction of the positive electrode 100, the negative electrode 200, and the separator 300),

[0190] 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 an end insulating layer containing particles and a binder, which is laminated from the end side of the collector layer to the side of the active material layer and is bonded to them, The particles account for 55% or more and 99.5% or less of the end insulating layer. The particles and the binder account for a proportion of 55.5% or more and 99% or less of the end insulating layer, The thickness of the end insulating layer in the stacking direction is not less than 1 / 20 and not more than 1 / 2 of the thickness of the active material layer in the stacking direction.

2. The electrode according to claim 1, wherein The thickness of the end insulating layer in the stacking direction is 1 / 10 or more and 1 / 5 or less of the thickness of the active material layer in the stacking direction.

3. The electrode according to claim 1, wherein The thickness of the end insulating layer in the stacking direction is 1 μm or more and 15 μm or less in a portion bonded to the current collecting layer or a portion bonded to the active material layer.

4. The electrode according to claim 3, wherein The end insulating layer has a thickness in the stacking direction of not less than 2 μm and not more than 5 μm.

5. The electrode according to claim 1, wherein The end insulating layer is stacked from the end side of the current collecting layer, passes through the side portion of the active material layer, reaches the end of the active material layer, and is bonded to the ends.

6. The electrode according to claim 1, wherein The end insulating layer is stacked between the active material layer and the current collecting layer from the end side of the current collecting layer to be bonded to these layers.

7. 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.

8. 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 comprises: Current collecting layer; an active material layer containing an active material and joined to the current collecting layer; and The end insulating layer contains particles and a binder and extends from one end side of the collector layer to the side of the active material layer to be bonded to the active material layer.

9. A method for manufacturing an electrode, the 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 an end insulating layer containing particles and a binder, which is laminated from the end side of the collector layer to the side of the active material layer and is bonded to them, The particles account for 55% or more and 99.5% or less of the end insulating layer. The particles and the binder account for a proportion of 55.5% or more and 99% or less of the end insulating layer, The thickness of the end insulating layer in the stacking direction is not less than 1 / 20 and not more than 1 / 2 of the thickness of the active material layer in the stacking direction. In the manufacturing method, using an end insulating layer slurry which is applied onto the collector layer and the active material layer and then forms the end insulating layer, wherein the end insulating layer slurry contains the particles, the binder, and a volatile solvent, The manufacturing method comprises: a coating step of coating the end insulating layer slurry on the current collecting layer and the active material layer, The shrinkage rate of the end insulating layer slurry during the drying process is greater than 1% and less than 40%.

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