Composite electrode plate and manufacturing method therefor, and solid state battery

Abstract

A composite electrode plate and its manufacturing method and a solid state battery are provided. The composite electrode plate includes an electrode plate body. At least part of side edges of the electrode plate body is provided with an edge sealing portion, and the edge sealing portion is made of an insulation material. The electrode plate body includes a current collector and a functional layer stacked with the current collector, and the edge sealing portion at least covers part of side edges of the current collector and part of side edges of the functional layer. By providing the edge sealing portion, the composite electrode plate can reduce the risk of short circuit during the hot-pressing process, the risk of coming into contact with water and oxygen during the manufacturing process, and the risk of occurring cracks or even fractures during use.

Description

COMPOSITE ELECTRODE PLATE AND MANUFACTURING METHOD THEREFOR,AND SOLID STATE BATTERYCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to U.S. Provisional Application No. 63 / 622,496, filed on January 18, 2024, which is hereby incorporated by reference in its entirety.TECHNICAL FIELD

[0002] This application relates to the field of battery technology, and in particular to a composite electrode plate and its manufacturing method, and a solid state battery.BACKGROUND

[0003] In the research, development and application of solid state batteries, bipolar stacked structures are widely regarded as an important means to improve battery energy density and performance. The battery cell of solid state batteries generally includes multiple composite electrode plates, each of which includes a current collector and a positive active material layer and a negative active material layer respectively arranged on opposite sides of the current collector; the multiple composite electrode plates are stacked in sequence, adjacent composite electrode plates are separated by a solid electrolyte layer, and the multiple composite electrode plates are combined with the solid electrolyte layers through hot-pressing process.

[0004] The current collector, the positive active material layer, the negative active material layer and the solid electrolyte layer may have different sizes, and the distance between the side edges of these layers is relatively small; during the hot-pressing process, the side edge of the positive active material layer and the side edge of the negative active material layer may stretch and come into contact under pressure, thereby resulting in short circuit.

[0005] In addition, since battery active materials and solid electrolyte materials are sensitive to water and oxygen, contact and reaction with water and oxygen will reduce the electrochemical performance of solid state batteries or even lead to their failure; currently, in the manufacturingprocess of solid state batteries, the composite electrode plates are in an exposed state, which poses a risk of the battery active materials and the solid electrolyte materials coming into contact with water and oxygen.

[0006] Moreover, during the use of solid state batteries, volume changes caused by charging and discharging processes, as well as vibrations experienced by solid state batteries, may lead to cracks or even fractures in the composite electrode plates inside solid state batteries (the positive active material layer, the negative active material layer and the solid electrolyte layer may have cracks or even fractures), thereby affecting the use performance and safety of solid state batteries.SUMMARY

[0007] The object of the present application is to provide a composite electrode plate that, by providing the edge sealing portion, can reduce the risk of short circuit during the hot-pressing process of the composite electrode plate, the risk of coming into contact with water and oxygen during the manufacturing process of the composite electrode plate, and the risk of occurring cracks or even fractures during use of the composite electrode plate.

[0008] The present application provides a composite electrode plate including an electrode plate body, wherein at least part of side edges of the electrode plate body is provided with an edge sealing portion, and the edge sealing portion is made of an insulation material; the electrode plate body includes a current collector and a functional layer stacked with the current collector, and the edge sealing portion at least covers part of side edges of the current collector and part of side edges of the functional layer.

[0009] In an achievable manner, the functional layer includes a first electrode material layer, and the first electrode material layer is arranged on a surface of one side of the current collector; the edge sealing portion at least covers part of side edges of the first electrode material layer.

[0010] In an achievable manner, the first electrode material layer is a positive active material layer or a negative active material layer.

[0011] In an achievable manner, the functional layer further includes a solid electrolyte layer, and the solid electrolyte layer is arranged on a surface of one side of the first electrode material layer away from the current collector; the edge sealing portion at least covers part of side edges of the solid electrolyte layer.

[0012] In an achievable manner, the solid electrolyte layer at least covers part of the side edges of the first electrode material layer.

[0013] In an achievable manner, the solid electrolyte layer includes a main body portion and a folded edge portion extending and protruding from a side edge of the main body portion towards the current collector, the main body portion is provided on a surface of one side of the first electrode material layer away from the current collector, and the folded edge portion at least covers part of the side edges of the first electrode material layer; the edge sealing portion at least partially covers an outer side wall of the folded edge portion.

[0014] In an achievable manner, the functional layer further includes a second electrode material layer, and the second electrode material layer is arranged on a surface of one side of the solid electrolyte layer away from the current collector, or the second electrode material layer is arranged on a surface of one side of the current collector away from the first electrode material layer; the edge sealing portion at least covers part of side edges of the second electrode material layer.

[0015] In an achievable manner, one of the first electrode material layer and the second electrode material layer is a positive active material layer, and the other is a negative active material layer.

[0016] In an achievable manner, along a thickness direction of the composite electrode plate, the upper and lower surfaces of the edge sealing portion do not exceed the upper and lower surfaces of the electrode plate body.

[0017] In an achievable manner, along the thickness direction of the composite electrode plate, upper and lower surfaces of the edge sealing portion are respectively flush with upper and lower surfaces of the electrode plate body.

[0018] In an achievable manner, an outer side wall of the edge sealing portion is a planar structure.

[0019] In an achievable manner, the edge sealing portion is provided on all the side edges of the electrode plate body, and the edge sealing portion covers all the side edges of the current collector and all the side edges of the functional layer.

[0020] In an achievable manner, a material of the edge sealing portion is insulation adhesive, and the edge sealing portion is fixed to the side edge(s) of the electrode plate body by adhering.

[0021] The present application also provides a manufacturing method for the composite electrode plate as described above, including:

[0022] SI : providing a current collector, and providing a functional layer on a surface of the current collector to obtain an electrode plate body;

[0023] S2: providing an edge sealing portion made of an insulation material on at least part of side edges of the electrode plate body to obtain a composite electrode plate, wherein the edge sealing portion at least covers part of side edges of the current collector and part of side edges of the functional layer.

[0024] In an achievable manner, in the step SI, the functional layer includes a first electrode material layer, and the first electrode material layer is arranged on a surface of one side of the current collector;

[0025] in the step S2, the edge sealing portion at least covers part of side edges of the first electrode material layer.

[0026] In an achievable manner, in the step SI, the functional layer further includes a solid electrolyte layer, and the solid electrolyte layer is arranged on a surface of one side of the first electrode material layer away from the current collector;

[0027] in the step S2, the edge sealing portion also at least covers part of side edges of the solid electrolyte layer.

[0028] In an achievable manner, in the step SI, the functional layer further includes a second electrode material layer, and the second electrode material layer is arranged on a surface of one side of the solid electrolyte layer away from the current collector, or the second electrode material layer is arranged on a surface of one side of the current collector away from the first electrode material layer;

[0029] in the step S2, the edge sealing portion also at least covers part of side edges of the second electrode material layer.

[0030] In an achievable manner, the manufacturing method for the composite electrode plate further includes:

[0031] S3 : hot-pressing the composite electrode plate.

[0032] In an achievable manner, the insulation material is an insulation adhesive, and the edge sealing portion is fixed to the side edge(s) of the electrode plate body by adhering.

[0033] The present application also provides a solid state battery, including multiple composite electrode plates as described above, wherein the multiple composite electrode plates are stacked along a thickness direction thereof.

[0034] The composite electrode plate provided in this application is provided with an insulating edge sealing portion on at least part of the side edges of the electrode plate body. On the one hand,the edge sealing portion can insulate and encapsulate at least part of the side edges of the functional layer, thereby reducing the risk of short circuit between the positive and negative active material layers during hot-pressing process. Meanwhile, during the hot-pressing process, the edge sealing portion can restrain the functional layer to prevent it from being excessively expanded, thereby reducing or avoiding the occurrence of cracks or even fractures in the functional layer due to high pressure during the hot-pressing process. On the other hand, the edge sealing portion can seal at least part of the side edges of the electrode plate body, thereby reducing the risk of the composite electrode plate coming into contact with water, oxygen, etc. during the manufacturing process. Moreover, the edge sealing portion can provide protection, reinforcement, and vibration reduction to the sides of the electrode plate body, thereby reducing the risk of cracks or even fractures in the composite electrode plate during use, and improving the electrochemical performance and safety of solid state batteries.BRIEF DESCRIPTION OF THE DRAWINGS

[0035] FIG. l is a schematic diagram of the three-dimensional structure of a composite electrode plate in an embodiment of the present application.

[0036] FIG. 2 is a schematic diagram of the three-dimensional structure of a composite electrode plate in another embodiment of the present application.

[0037] FIG. 3 is a schematic cross-sectional view taken along the A-A line in FIG. 1.

[0038] FIG. 4 is a schematic cross-sectional view of a composite electrode plate in another embodiment of the present application.

[0039] FIG. 5 is a schematic cross-sectional view of a composite electrode plate in another embodiment of the present application.

[0040] FIG. 6 is a schematic cross-sectional view of a composite electrode plate in another embodiment of the present application.

[0041] FIG. 7 is a schematic cross-sectional view of a composite electrode plate in another embodiment of the present application.

[0042] FIG. 8 is a schematic cross-sectional view of a composite electrode plate in another embodiment of the present application.

[0043] FIG. 9 is a schematic cross-sectional view of a composite electrode plate in another embodiment of the present application.

[0044] FIG. 10 is a schematic cross-sectional view of a composite electrode plate in another embodiment of the present application.

[0045] FIG. 11 is a schematic cross-sectional view of a composite electrode plate in another embodiment of the present application.

[0046] FIG. 12 is a schematic cross-sectional view of a composite electrode plate in another embodiment of the present application.

[0047] FIG. 13 is a schematic cross-sectional view of a composite electrode plate in another embodiment of the present application.

[0048] FIG. 14 is a schematic cross-sectional view of a composite electrode plate in another embodiment of the present application.

[0049] FIG. 15 is a schematic cross-sectional view of a solid state battery cell in an embodiment of the present application.

[0050] FIG. 16 is a schematic cross-sectional view of a solid state battery cell in another embodiment of the present application.

[0051] FIG. 17 is a schematic cross-sectional view of a solid state battery cell in another embodiment of the present application.

[0052] FIG. 18 is a schematic cross-sectional view of a solid state battery cell in another embodiment of the present application.

[0053] FIG. 19 is a schematic cross-sectional view of a solid state battery cell in another embodiment of the present application.

[0054] In the figures: 100-composite electrode plate, 1 -electrode plate body, 11 -current collector, 12-functional layer, 121 -first electrode material layer, 122-second electrode material layer, 120A- positive active material layer, 120B-negative active material layer, 123-solid electrolyte layer, 123A-main body portion, 123B-folded edge portion, 2-edge sealing portion, 3-current collector layer, 4-first electrode tab, 5-second electrode tab.DETAILED DESCRIPTION OF THE EMBODIMENTS

[0055] The following will provide a further detailed description of the specific implementations of the present application in conjunction with the accompanying drawings and embodiments. The following embodiments are used to illustrate the present application, but are not intended to limit the scope of the present application.

[0056] The terms “first”, “second”, “third”, “fourth”, etc. (if any) in the specification and claims of the present application are only used to distinguish similar objects, and are not intended to be used to describe a specific sequence or order.

[0057] The terms “up”, “down”, “left”, “right”, “front”, “back”, “top”, “bottom” (if any) in the specification and claims of the present application are defined based on the position of the structure in the figures and the position between the structures in the figures, only for the clarity and convenience of expressing the technical solution. It should be understood that the use of these directional words should not limit the scope of protection in the present application.

[0058] As shown in FIGS. 1 and 3, a composite electrode plate 100 for solid state batteries is provided in an embodiment of the present application. The composite electrode plate 100 includes an electrode plate body 1, and at least part of side edges of the electrode plate body 1 is provided with an edge sealing portion 2. The edge sealing portion 2 is made of an insulation material. The electrode plate body 1 includes a current collector 11 and a functional layer 12 stacked with the current collector 11. Specifically, the composite electrode plate 100 has a thickness direction T, and the functional layer 12 and the current collector 11 are stacked along the thickness direction T. The edge sealing portion 2 at least covers part of side edges of the current collector 11 and part of side edges of the functional layer 12.

[0059] The composite electrode plate provided in this embodiment is provided with an insulating edge sealing portion 2 on at least part of the side edges of the electrode plate body 1. On the one hand, the edge sealing portion 2 can insulate and encapsulate at least part of the side edges of the functional layer 12, thereby reducing the risk of short circuit between the positive and negative active material layers during hot-pressing process (during the hot-pressing process, even if the positive and negative active material layers are stretched, the edge sealing portion 2 can effectively prevent them from coming into contact). Meanwhile, during the hot-pressing process, the edge sealing portion 2 can restrain the functional layer 12 to prevent it from being excessively expanded,thereby reducing or avoiding the occurrence of cracks or even fractures in the functional layer 12 due to high pressure during the hot-pressing process. On the other hand, the edge sealing portion 2 can seal at least part of the side edges of the electrode plate body 1, thereby reducing the risk of the composite electrode plate 100 coming into contact with water, oxygen, etc. during the manufacturing process (the edge sealing portion 2 can reduce the risk of the current collector 11 and the functional layer 12 coming into contact with water, oxygen, etc.). Moreover, the edge sealing portion 2 can provide protection, reinforcement, and vibration reduction to the sides of the electrode plate body 1 (especially when the material of the edge sealing portion 2 is an insulation adhesive, which has a certain degree of elasticity, the vibration reduction can be better realized), thereby reducing the risk of cracks or even fractures in the composite electrode plate 100 during use (especially reducing the risk of cracks or even fractures in the functional layer 12), and improving the electrochemical performance and safety of solid state batteries.

[0060] As one embodiment, the current collector 11 can be aluminum foil, roughened aluminum foil, perforated aluminum foil, copper aluminum composite foil, stainless steel foil, roughened stainless steel foil, or perforated stainless steel foil, etc.

[0061] As shown in FIG. 3, as one embodiment, the functional layer 12 includes a first electrode material layer 121, and the first electrode material layer 121 is arranged on the surface of one side of the current collector 11. The edge sealing portion 2 at least covers part of side edges of the first electrode material layer 121. Specifically, during manufacturing, the first electrode material layer 121 can be first provided on the current collector 11 to obtain the electrode plate body 1, and thereafter, the edge sealing portion 2 is provided on the side edge(s) of the electrode plate body 1 to obtain the composite electrode plate 100.

[0062] As shown in FIG. 3, as one embodiment, the first electrode material layer 121 is a positive active material layer 120A. The positive active material in the positive active material layer 120A can be the positive active material that is commonly used in lithium-ion secondary batteries. For example, the positive active material can be selected from one or more of olivine structured lithium metal oxides, layered structured lithium metal oxides, and spinel structured lithium metal oxides, or the positive active material can be selected from one or more of lithium nickel cobalt manganese, lithium cobalt oxide, lithium nickel oxide, lithium nickel cobalt aluminum, lithium iron phosphate, and lithium rich manganese based materials. The positive active material layer 120A can be formed by electrostatic spraying, slurry coating, or dry filming.

[0063] As shown in FTG. 4, as another embodiment, the first electrode material layer 121 is a negative active material layer 120B. The negative active material in the negative active material layer 120B can be the negative active material that is commonly used in lithium-ion secondary batteries. For example, the negative active material can be selected from one or more of graphite, silicon, silicon oxide, silicon carbon, lithium titanate, metallic lithium, and lithium alloy. The negative active material layer 120B can be formed by electrostatic spraying, slurry coating, or dry fdming.

[0064] In some embodiments, a design of no negative electrode can also be adopted, in which case the negative active material layer 120B can be replaced with a negative electrode free structural layer (not shown), that is, the first electrode material layer 121 can also be a negative electrode free structural layer. The negative electrode free structural layer includes one or more of a carbon layer and a metal layer, wherein the material of the carbon layer can be various crystalline carbon, amorphous carbon, and transition carbon, etc., and the material of the metal layer includes, but is not limited to, metals such as gold, silver, tin, aluminum, zinc, magnesium, silicon, etc. that can undergo alloying reactions with metallic lithium. The carbon layer and the metal layer can be formed through processes such as coating, evaporation, sputtering, bonding, or pressing.

[0065] As one embodiment, the electrode plate body 1 is a quadrilateral structure (specifically can be a rectangular structure or a square structure), and the edge sealing portion 2 can be provided on one side, two sides (including adjacent or opposite sides), three sides, or four sides of the electrode plate body 1. Of course, the electrode plate body 1 can also have other shapes, such as circular, polygonal, or irregular shapes, and in this case, the edge sealing portion 2 can be provided on at least part of the side edges of the electrode plate body 1 according to requirements.

[0066] As shown in FIG. 1, as one embodiment, the edge sealing portion 2 is provided on opposite sides of the electrode plate body 1. Specifically, the edge sealing portion 2 can be provided on opposite sides of the electrode plate body 1 along its length or width direction. As shown in FIG. 2, as another embodiment, the edge sealing portion 2 is provided on all the side edges of the electrode plate body 1, and the edge sealing portion 2 covers all the side edges of the current collector 11 and all the side edges of the functional layer 12, thereby further improving the encapsulation, insulation, and protection effects of the edge sealing portion 2. As shown in FIGS. 1 and 2, the edge sealing portion 2 on each side edge of the electrode plate body 1 is a continuous elongated structure so as to cover the entire side edge.

[0067] As shown in FIG. 3, as one embodiment, along the thickness direction T of the composite electrode plate 100, the upper and lower surfaces of the edge sealing portion 2 do not exceed the upper and lower surfaces of the electrode plate body 1, so as to facilitate the stacking of the composite electrode plate 100 with other composite electrode plates 100 and / or the stacking of the composite electrode plate 100 with other structural layers, and ensure that there is no gap between the composite electrode plate 100 and other composite electrode plates 100 and / or between the composite electrode plate 100 and other structural layers after stacking (specifically as shown in FIG. 15 to FIG. 19).

[0068] As shown in FIG. 3, as one embodiment, along the thickness direction T of the composite electrode plate 100, the upper and lower surfaces of the edge sealing portion 2 are respectively flush with the upper and lower surfaces of the electrode plate body 1, so that after the composite electrode plate 100 is stacked with other composite electrode plates 100 and / or the composite electrode plate 100 is stacked with other structural layers to form a solid state battery, the edge sealing portions 2 on adjacent composite electrode plates 100 and / or the edge sealing portion 2 on the composite electrode plate 100 and other structural layers can abut against each other tightly (specifically as shown in FIG. 15 to FIG. 19), to improve sealing and insulation properties.

[0069] As shown in FIG. 3, as one embodiment, the outer side wall of the edge sealing portion 2 is a planar structure, thereby improving the flatness of the outer side wall of the composite electrode plate 100, and thus improving the flatness of the outer side wall of the solid state battery (specifically as shown in FIG. 18 and FIG. 19), which facilitates the encapsulation of the solid state battery.

[0070] As one embodiment, the material of the edge sealing portion 2 is insulation adhesive, and the edge sealing portion 2 is fixed to the side edge(s) of the electrode plate body 1 by adhering. The insulation adhesive not only has good insulation performance, sealing performance, and structural strength, but also is convenient to use. The insulation adhesive can be provided at the side edge(s) of the electrode plate body 1 by injection, bonding, or coating (such as roller coating or spray coating).

[0071] As one embodiment, the type of the insulation adhesive can be selected according to the manufacturing process of the solid state battery (e.g., according to the hot-pressing temperature). The insulation adhesive can specifically be hot melt adhesive, light curing adhesive, or two-component adhesive. The melting temperature (or the softening temperature) of the insulation adhesive can be 50°C-500°C, or 80°C-300°C, or 100°C-250°C, or 15O°C-35O°C, or 120°C-400°C.

[0072] As one embodiment, in order to improve the high temperature resistance and aging resistance of the insulation adhesive, this embodiment also provides an insulation adhesive. The insulation adhesive includes a first component and at least a second component, wherein the first component is aramid. The mass content of the first component in the insulation adhesive is greater than or equal to 50%, and the rest is the second component. The second component includes, but is not limited to, one or more of polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyamide, polyoxymethylene, polycarbonate, polyphenylene ether, polysulfone, rubber, and other thermoplastic materials, and polyimide, alumina, boehmite, and other high-temperature resistant materials.

[0073] As shown in FIGS. 5 and 6, as another embodiment, the functional layer 12 further includes a solid electrolyte layer 123, and the solid electrolyte layer 123 is arranged on the surface of one side of the first electrode material layer 121 away from the current collector 11. The edge sealing portion 2 at least covers part of side edges of the solid electrolyte layer 123. By sealing the current collector 11, the first electrode material layer 121 and the solid electrolyte layer 123 together, it is more conducive to the interface contact between the first electrode material layer 121 and the solid electrolyte layer 123, thereby improving the performance of the solid state battery.

[0074] Specifically, as shown in FIG. 5, the first electrode material layer 121 is a positive active material layer 120A, and in this case, the positive active material layer 120A can be first provided on the current collector 11, the solid electrolyte layer 123 is then provided on the positive active material layer 120A to obtain the electrode plate body 1, and thereafter, the edge sealing portion 2 is provided on the side edge(s) of the electrode plate body 1 to obtain the composite electrode plate 100. As shown in FIG. 6, the first electrode material layer 121 is a negative active material layer 120B, and in this case, the negative active material layer 120B can be first provided on the current collector 11, the solid electrolyte layer 123 is then provided on the negative active material layer 120B to obtain the electrode plate body 1, and thereafter, the edge sealing portion 2 is provided on the side edge(s) of the electrode plate body 1 to obtain the composite electrode plate 100.

[0075] As one embodiment, specifically, the solid electrolyte layer 123 can be one or more of sulfide solid electrolyte, halide solid electrolyte, oxide solid electrolyte, or polymer solidelectrolyte. The solid electrolyte layer 123 can be formed by electrostatic spraying, slurry coating, or dry filming.

[0076] As shown in FIGS. 5 and 6, as one embodiment, the solid electrolyte layer 123 is a flat layered structure as a whole, and the solid electrolyte layer 123 is stacked with the first electrode material layer 121 along the thickness direction T.

[0077] As shown in FIGS. 7 and 8, as another embodiment, the solid electrolyte layer 123 at least covers part of the side edges of the first electrode material layer 121 (in other embodiments, the solid electrolyte layer 123 also at least covers part of the side edges of the current collector 11), and then the side edge is sealed by the edge sealing portion 2. By providing dual protection through the solid electrolyte layer 123 and the edge sealing portion 2, the composite electrode plate 100 can better avoid the risk of short circuit and fractures during manufacturing or use.

[0078] Specifically, the solid electrolyte layer 123 includes a main body portion 123 A and a folded edge portion 123B extending and protruding from a side edge of the main body portion 123A towards the current collector 11. The main body portion 123 A has a flat layered structure, and the main body portion 123A is arranged on the surface of one side of the first electrode material layer 121 away from the current collector 11, that is, the main body portion 123A and the first electrode material layer 121 are stacked along the thickness direction T. The folded edge portion 123B at least covers part of the side edges of the first electrode material layer 121 (in other embodiments, the folded edge portion 123B also at least covers part of the side edges of the current collector 11), and the edge sealing portion 2 at least partially covers the outer side wall of the folded edge portion 123B. As one embodiment, the folded edge portion 123B covers the entire side edge of the first electrode material layer 121 along the thickness direction T, and the edge sealing portion 2 covers the outer side wall of the entire folded edge portion 123B along the thickness direction T.

[0079] Specifically, as shown in FIG. 7, the first electrode material layer 121 is a positive active material layer 120A, and in this case, the positive active material layer 120A can be first provided on the current collector 11, the solid electrolyte layer 123 is then provided on the positive active material layer 120A, and the solid electrolyte layer 123 covers the upper surface and at least part of the side edges of the positive active material layer 120A to obtain the electrode plate body 1. Thereafter, the edge sealing portion 2 is provided on the side edge(s) of the electrode plate body 1 to obtain the composite electrode plate 100. As shown in FIG. 8, the first electrode material layer 121 is a negative active material layer 120B, and in this case, the negative active material layer120B can be first provided on the current collector 11 , the solid electrolyte layer 123 is then provided on the negative active material layer 120B, and the solid electrolyte layer 123 covers the upper surface and at least part of the side edges of the negative active material layer 120B to obtain the electrode plate body 1. Thereafter, the edge sealing portion 2 is provided on the side edge(s) of the electrode plate body 1 to obtain the composite electrode plate 100.

[0080] As shown in FIGS. 9 to 14, as another embodiment, the functional layer 12 further includes a second electrode material layer 122. The second electrode material layer 122 is arranged on the surface of one side of the solid electrolyte layer 123 away from the current collector 11, or the second electrode material layer 122 is arranged on the surface of one side of the current collector 11 away from the first electrode material layer 121. The edge sealing portion 2 at least covers part of the side edges of the second electrode material layer 122. One of the first electrode material layer 121 and the second electrode material layer 122 is a positive active material layer 120A, and the other is a negative active material layer 120B. By sealing the current collector 11, the first electrode material layer 121, the solid electrolyte layer 123 and the second electrode material layer 122 together, it is more conducive to the interface contact between the first electrode material layer 121 and / or the second electrode material layer 122 and the solid electrolyte layer 123, thereby improving the performance of the solid state battery.

[0081] As shown in FIG. 9, the first electrode material layer 121 is a positive active material layer 120A, the second electrode material layer 122 is a negative active material layer 120B, and the second electrode material layer 122 is arranged on the surface of one side of the solid electrolyte layer 123 away from the current collector 11. In this case, the positive active material layer 120A can be first provided on the current collector 11, the solid electrolyte layer 123 is then provided on the positive active material layer 120A, and the negative active material layer 120B is then provided on the solid electrolyte layer 123 to obtain the electrode plate body 1. Thereafter, the edge sealing portion 2 is provided on the side edge(s) of the electrode plate body 1 to obtain the composite electrode plate 100.

[0082] As shown in FIG. 10, the first electrode material layer 121 is a negative active material layer 120B, the second electrode material layer 122 is a positive active material layer 120A, and the second electrode material layer 122 is arranged on the surface of one side of the solid electrolyte layer 123 away from the current collector 11. In this case, the negative active material layer 120B can be first provided on the current collector 11, the solid electrolyte layer 123 is thenprovided on the negative active material layer 120B, and the positive active material layer 120A is then provided on the solid electrolyte layer 123 to obtain the electrode plate body 1. Thereafter, the edge sealing portion 2 is provided on the side edge(s) of the electrode plate body 1 to obtain the composite electrode plate 100.

[0083] As shown in FIG. 13, the first electrode material layer 121 is a positive active material layer 120A, the second electrode material layer 122 is a negative active material layer 120B, and the second electrode material layer 122 is arranged on the surface of one side of the current collector 11 away from the first electrode material layer 121. In this case, the positive active material layer 120 A can be first provided on one side of the current collector 11, the solid electrolyte layer 123 is then provided on the positive active material layer 120A, and the negative active material layer 120B is then provided on the other side of the current collector 11 to obtain the electrode plate body 1. Thereafter, the edge sealing portion 2 is provided on the side edge(s) of the electrode plate body 1 to obtain the composite electrode plate 100.

[0084] As shown in FIG. 14, the first electrode material layer 121 is a negative active material layer 1206, the second electrode material layer 122 is a positive active material layer 120A, and the second electrode material layer 122 is arranged on the surface of one side of the current collector 11 away from the first electrode material layer 121. In this case, the negative active material layer 120B can be first provided on one side of the current collector 11, the solid electrolyte layer 123 is then provided on the negative active material layer 120B, and the positive active material layer 120A is then provided on the other side of the current collector 11 to obtain the electrode plate body 1. Thereafter, the edge sealing portion 2 is provided on the side edge(s) of the electrode plate body 1 to obtain the composite electrode plate 100.

[0085] As shown in FIGS. 9, 10, 13, and 14, as one embodiment, the solid electrolyte layer 123 is a flat layered structure as a whole, and the solid electrolyte layer 123 is stacked with the first electrode material layer 121 along the thickness direction T.

[0086] As shown in FIGS. 11 and 12, as another embodiment, the solid electrolyte layer 123 at least covers part of the side edges of the first electrode material layer 121 (in other embodiments, the solid electrolyte layer 123 also at least covers part of the side edges of the current collector 11 and / or part of the side edges of the second electrode material layer 122), and then the side edge is sealed by the edge sealing portion 2.

[0087] As shown in FIG. 11 , the first electrode material layer 121 is a positive active material layer 120A, the second electrode material layer 122 is a negative active material layer 120B, and the second electrode material layer 122 is arranged on the surface of one side of the solid electrolyte layer 123 away from the current collector 11. In this case, the positive active material layer 120A can be first provided on the current collector 11, and the solid electrolyte layer 123 is then provided on the positive active material layer 120A, wherein the solid electrolyte layer 123 covers the upper surface and at least part of the side edges of the positive active material layer 120A. The negative active material layer 120B is then provided on the solid electrolyte layer 123 to obtain the electrode plate body 1. Thereafter, the edge sealing portion 2 is provided on the side edge(s) of the electrode plate body 1 to obtain the composite electrode plate 100.

[0088] As shown in FIG. 12, the first electrode material layer 121 is a negative active material layer 120B, the second electrode material layer 122 is a positive active material layer 120A, and the second electrode material layer 122 is arranged on the surface of one side of the solid electrolyte layer 123 away from the current collector 11. In this case, the negative active material layer 120B can be first provided on the current collector 11, and the solid electrolyte layer 123 is then provided on the negative active material layer 120B, wherein the solid electrolyte layer 123 covers the upper surface and at least part of the side edges of the negative active material layer 120B. The positive active material layer 120A is then provided on the solid electrolyte layer 123 to obtain the electrode plate body 1. Thereafter, the edge sealing portion 2 is provided on the side edge(s) of the electrode plate body 1 to obtain the composite electrode plate 100.

[0089] This embodiment also provides a manufacturing method for the composite electrode plate as described above, and the manufacturing method for the composite electrode plate includes:

[0090] SI : providing a current collector 11, and providing a functional layer 12 on the surface of the current collector 11 to obtain an electrode plate body 1;

[0091] S2: providing an edge sealing portion 2 made of insulation material on at least part of side edges of the electrode plate body 1 to obtain a composite electrode plate 100, wherein the edge sealing portion 2 at least covers part of side edges of the current collector 11 and part of side edges of the functional layer 12.

[0092] As shown in FIGS. 3 and 4, as one embodiment, in the step SI above, the functional layer 12 includes a first electrode material layer 121, and the first electrode material layer 121 is arrangedon the surface of one side of the current collector 11 . In the step S2 above, the edge sealing portion 2 at least covers part of side edges of the first electrode material layer 121.

[0093] Specifically, during manufacturing, the first electrode material layer 121 can be first provided on the current collector 11 to obtain the electrode plate body 1, and an insulation material is then provided on the side edge(s) of the electrode plate body 1 to form the edge sealing portion 2, thereby obtaining the composite electrode plate 100.

[0094] As shown in FIGS. 5 to 8, as one embodiment, in the step SI above, the functional layer 12 further includes a solid electrolyte layer 123, and the solid electrolyte layer 123 is arranged on the surface of one side of the first electrode material layer 121 away from the current collector 11. In the step S2 above, the edge sealing portion 2 also at least covers part of side edges of the solid electrolyte layer 123.

[0095] Specifically, during manufacturing, the first electrode material layer 121 can be first provided on the current collector 11, and the solid electrolyte layer 123 is then provided on the first electrode material layer 121 to obtain the electrode plate body 1. Thereafter, an insulation material is provided on the side edge(s) of the electrode plate body 1 to form the edge sealing portion 2, thereby obtaining the composite electrode plate 100.

[0096] As shown in FIGS. 9 to 14, as one embodiment, in the step SI above, the functional layer 12 further includes a second electrode material layer 122, wherein the second electrode material layer 122 is arranged on the surface of one side of the solid electrolyte layer 123 away from the current collector 11, or the second electrode material layer 122 is arranged on the surface of one side of the current collector 11 away from the first electrode material layer 121. In the step S2 above, the edge sealing portion 2 also at least covers part of side edges of the second electrode material layer 122.

[0097] Specifically, during manufacturing, the first electrode material layer 121 can be first provided on the current collector 11, and the solid electrolyte layer 123 is then provided on the first electrode material layer 121. Then, the second electrode material layer 122 is provided on the solid electrolyte layer 123, or the second electrode material layer 122 is provided on the surface of one side of the current collector 11 away from the first electrode material layer 121, to obtain the electrode plate body 1. Thereafter, an insulation material is provided on the side edge(s) of the electrode plate body 1 to form the edge sealing portion 2, thereby obtaining the composite electrode plate 100.

[0098] As one embodiment, in the step S2 above, the insulation material is an insulation adhesive, and the edge sealing portion 2 is fixed to the side edge(s) of the electrode plate body 1 by adhering. The insulation adhesive can be provided at the side edge of the electrode plate body 1 by injection, bonding, or coating.

[0099] As one embodiment, the manufacturing method for the composite electrode plate further includes:

[0100] S3: after the step S2 above, hot-pressing the composite electrode plate 100.

[0101] By hot-pressing the composite electrode plate 100, better interface performance can be obtained (including the interface performance between the first electrode material layer 121 and the current collector 11, and / or the interface performance between the solid electrolyte layer 123 and the first electrode material layer 121, and / or the interface performance between the second electrode material layer 122 and the solid electrolyte layer 123, and / or the interface performance between the second electrode material layer 122 and the current collector 11), thereby improving the electrochemical performance of the solid state battery.

[0102] Specifically, the hot-pressing temperature can be determined based on the surface melting temperature of the solid electrolyte materials, which exists in the solid electrolyte layer 123, the first electrode material layer 121, and / or the second electrode material layer 122. For example, in some embodiments, the hot-pressing temperature may be between 80°C and 500°C, or between 100°C and 300°C, or between 150°C and 400°C, or between 180°C and 35O°C. The hot-pressing pressure can be determined according to the selection of materials. For example, in some embodiments, the hot-pressing pressure is between lOMpa and 500Mpa, or between 50Mpa and 500Mpa, or between lOOMpa and 300Mpa, or between 50Mpa and 250Mpa. The hot-pressing time can be determined according to the degree of melting of the materials. For example, in some embodiments, the hot-pressing time is between 15min and 60min, or between lOmin and 60min, or between 30min and 120min, or between 60min and 600min.

[0103] As shown in FIG. 15 to FIG. 19, the embodiments of the present application also provide a solid state battery, particularly an all-solid state battery. The solid state battery includes multiple composite electrode plates 100 as described above, and the multiple composite electrode plates 100 are stacked along the thickness direction T to form a solid state battery cell (not labeled), wherein the composite electrode plate 100 can be any one or more of the composite electrode plates 100 shown in FIG. 3 to FIG. 14.

[0104] Generally, during the stacking process of the multiple composite electrode plates 100, a hot-pressing treatment is required for stacking each layer of the composite electrode plate 100 (i.e., after stacking another composite electrode plate 100 on one composite electrode plate 100, a hot- pressing treatment is required), to ensure that each solid electrolyte layer 123 is in full contact with the adjacent positive active material layer 120A and negative active material layer 120B.

[0105] It should be noted that, as shown in FIG. 15, when multiple composite electrode plates 100 as shown in FIG. 3 are stacked to form the solid state battery cell, since the composite electrode plate 100 is provided with only the positive active material layer 120A and is not provided with the negative active material layer 120B and the solid electrolyte layer 123, this type of composite electrode plate 100 therefore needs to be combined with the negative active material layer 120B and the solid electrolyte layer 123 during manufacturing of the solid state battery.

[0106] It can be understood that when multiple composite electrode plates 100 as shown in FIG. 4 are stacked to form the solid state battery cell, since the composite electrode plate 100 is provided with only the negative active material layer 120B and is not provided with the positive active material layer 120A and the solid electrolyte layer 123, this type of composite electrode plate 100 therefore needs to be combined with the positive active material layer 120A and the solid electrolyte layer 123 during manufacturing of the solid state battery.

[0107] As shown in FIGS. 16 and 17, when multiple composite electrode plates 100 as shown in FIG. 5 or FIG. 7 are stacked to form the solid state battery cell, since the composite electrode plate 100 is provided with only the positive active material layer 120A and the solid electrolyte layer 123, and is not provided with the negative active material layer 120B, this type of composite electrode plate 100 therefore needs to be combined with the negative active material layer 120B during manufacturing of the solid state battery.

[0108] It can be understood that when multiple composite electrode plates 100 as shown in FIG. 6 or FIG. 8 are stacked to form the solid state battery cell, since the composite electrode plate 100 is provided with only the negative active material layer 120B and the solid electrolyte layer 123, and is not provided with the positive active material layer 120A, this type of composite electrode plate 100 therefore needs to be combined with the positive active material layer 120A during manufacturing of the solid state battery.

[0109] As shown in FIGS. 18 and 19, when the solid state battery is stacked using a plurality of any one of the composite electrode plates 100 as shown in FIGS. 9 to 14, since the compositeelectrode plates 100 are provided with the positive active material layer 120 A, the negative active material layer 120B and the solid electrolyte layer 123 at the same time, this type of composite electrode plate 100 therefore can be directly stacked and used during manufacturing of the solid state battery.

[0110] As shown in FIG. 15 to FIG. 19, as one embodiment, the solid state battery further includes a first electrode tab 4 and a second electrode tab 5. The first electrode tab 4 and the second electrode tab 5 are respectively electrically connected to the opposite sides of the solid state battery cell, thereby leading out the solid state battery cell. The first electrode tab 4 and the second electrode tab 5 are used for electrical connection with external devices (not shown). One of the first electrode tab 4 and the second electrode tab 5 serves as the positive electrode tab and the other as the negative electrode tab.

[0111] As shown in FIG. 15 to FIG. 18, as one embodiment, the outermost layer on one side of the solid state battery cell is the current collector 11 (i.e., the current collector 11 in the composite electrode plate 100 on this side is exposed), and the second electrode tab 5 is electrically connected to the current collector 11, while the other side of the solid state battery cell is stacked with a current collector layer 3 (as the current collector 11 in the composite electrode plate 100 on this side is not exposed, an additional current collector layer 3 is thus required), and the first electrode tab 4 is electrically connected to the current collector layer 3. The specific material of the current collector layer 3 can be stainless steel, copper, aluminum, composite foil (such as copper aluminum composite foil, copper stainless steel composite foil), etc. As shown in FIG. 19, in another embodiment, when the current collectors 11 on opposite sides of the solid state battery cell are not exposed, it is generally necessary to provide the current collector layer 3 on both sides of the solid state battery cell to facilitate connection with the first electrode tab 4 and the second electrode tab 5.

[0112] Example 1

[0113] Referring to FIGS. 3 and 15, a composite electrode plate and a solid state battery cell are prepared. The manufacturing method for the composite electrode plate includes:

[0114] SI : providing a current collector, and providing a functional layer on the surface of the current collector to obtain an electrode plate body, wherein the functional layer includes a first electrode material layer, and the first electrode material layer is provided on the surface of one side of the current collector;

[0115] S2: providing an edge sealing portion made of an insulation adhesive on at least part of side edges of the electrode plate body to obtain a composite electrode plate, wherein the edge sealing portion at least covers part of side edges of the current collector and part of side edges of the functional layer (the specific structure of the composite electrode plate can refer to FIG. 3).

[0116] Specifically, the current collector is a copper aluminum composite foil, and the current collector has a quadrilateral structure. The first electrode material layer is a positive active material layer, which includes positive active material, conductive agent, binder, and solid electrolyte as its components, wherein the ratio (mass ratio) of the four is 80:2:2: 16, the positive active material is LiNiosCoo 1Mno 1O2, the conductive agent is CNTs (carbon nanotubes), the binder is SBR (styrene butadiene rubber), and the solid electrolyte is LiePSsCl. The insulation adhesive is hot melt adhesive and made of PP (polypropylene). When manufacturing the composite electrode plate, the positive active material, the conductive agent, the binder and the solid electrolyte are mixed in a solvent to form a slurry. The slurry is coated on the aluminum foil side of the copper aluminum composite foil and dried to obtain an electrode plate body with a quadrilateral structure. Then, the insulation adhesive is provided on four side edges of the electrode plate body, so that the upper and lower surfaces of the insulation adhesive are on the same horizontal plane as the upper and lower surfaces of the electrode plate body to obtain a composite electrode plate.

[0117] A solid electrolyte layer is provided on the composite electrode plate. The solid electrolyte layer is prepared by dry filming method, and the material of the solid electrolyte layer is LLZTO (tantalum doped lithium lanthanum zirconium oxide), which is an oxide solid electrolyte. Then, a second electrode material layer is provided on the solid electrolyte layer. The second electrode material layer is prepared by dry filming method. The second electrode material layer is a negative active material layer, and the material of the second electrode material layer is graphite. The composite electrode plate, the solid electrolyte layer and the second electrode material layer are subjected to hot-pressing treatment, with a hot-pressing temperature of 120°C, a hot-pressing pressure of 300Mpa, and a hot-pressing time of 30 minutes, to form a battery unit. Then, multiple battery units are stacked and connected in series, and shaped by hot-pressing. Finally, electrode tabs are led out on both sides to obtain a solid state battery cell as shown in FIG. 15.

[0118] Specifically, due to the edge sealing portion on the composite electrode plate, the edge sealing portion can block external water, oxygen, etc., protect the sulfide solid electrolyte in the positive active material layer, and improve the performance of the positive active material layer.Further, the edge sealing portion can also avoid the problem of short circuit between the positive active material layer and the negative active material layer during the hot-pressing process, thereby improving the yield rate of the battery. Meanwhile, the edge sealing portion can also restrain the expansion of the positive active material layer, thereby avoiding the fracture of the positive active material layer caused by high pressure during the hot-pressing process.

[0119] Example 2

[0120] Referring to FIGS. 5 and 16, a composite electrode plate and a solid state battery cell are prepared. The manufacturing method for the composite electrode plate includes:

[0121] SI : providing a current collector, and providing a functional layer on the surface of the current collector to obtain an electrode plate body, wherein the functional layer includes a first electrode material layer and a solid electrolyte layer, the first electrode material layer is arranged on the surface of one side of the current collector, and the solid electrolyte layer is arranged on the surface of one side of the first electrode material layer away from the current collector;

[0122] S2: providing an edge sealing portion made of an insulation adhesive on at least part of side edges of the electrode plate body to obtain a composite electrode plate, wherein the edge sealing portion at least covers part of side edges of the current collector and part of side edges of the functional layer (the specific structure of the composite electrode plate can refer to FIG. 5).

[0123] Specifically, the current collector is a copper aluminum composite foil, and the current collector has a quadrilateral structure. The first electrode material layer is a positive active material layer, which includes positive active material, conductive agent, binder, and solid electrolyte as its components, wherein the ratio (mass ratio) of the four is 83:2:2:13, the positive active material is LiNio.7Coo.1Mno.2O2, the conductive agent is SP (conductive carbon black), the binder is SBR (styrene butadiene rubber), and the solid electrolyte is LiioGeP2Si2. The insulation adhesive is a two-component adhesive, with the first component being aramid, accounting for 68% by mass, and the second component being PE (polyethylene), accounting for 32%. When manufacturing the composite electrode plate, the positive active material, the conductive agent, the binder and the solid electrolyte are mixed in a solvent to form a slurry. The slurry is coated on the aluminum foil side of the copper aluminum composite foil and dried to form the first electrode material layer; then, the solid electrolyte layer is provided on the first electrode material layer to obtain an electrode plate body with a quadrilateral structure. The solid electrolyte layer is prepared by dry filming method, and the material of the solid electrolyte layer is LiioGeP2Si2, which is a sulfidesolid electrolyte. Then, the insulation adhesive is provided on four side edges of the electrode plate body, so that the upper and lower surfaces of the insulation adhesive are on the same horizontal plane as the upper and lower surfaces of the electrode plate body to obtain a composite electrode plate.

[0124] A second electrode material layer is provided on the composite electrode plate. The second electrode material layer is prepared by dry filming method. The second electrode material layer is a negative active material layer, and the material of the second electrode material layer is silicon. The composite electrode plate and the second electrode material layer are subjected to hot-pressing treatment, with a hot-pressing temperature of 180°C, a hot-pressing pressure of 500Mpa, and a hot-pressing time of 15 minutes, to form a battery unit. Then, multiple battery units are stacked and connected in series, and shaped by hot-pressing. Finally, electrode tabs are led out on both sides to obtain a solid state battery cell as shown in FIG. 16.

[0125] Specifically, due to the edge sealing portion on the composite electrode plate, the edge sealing portion can block external water, oxygen, etc., protect the sulfide solid electrolyte in the positive active material layer and the solid electrolyte layer, and improve the performance of the positive active material layer and the solid electrolyte layer. Further, the edge sealing portion can also avoid the problem of short circuit between the positive active material layer and the negative active material layer during the hot-pressing process, thereby improving the yield rate of the battery. Meanwhile, the edge sealing portion can also restrain the expansion of the positive active material layer and the solid electrolyte layer, thereby avoiding the fracture of the positive active material layer and the solid electrolyte layer due to high pressure during the hot-pressing process.

[0126] Example 3

[0127] Referring to FIGS. 7 and 17, a composite electrode plate and a solid state battery cell are prepared. The manufacturing method for the composite electrode plate includes:

[0128] SI: providing a current collector, and providing a functional layer on the surface of the current collector to obtain an electrode plate body, wherein the functional layer includes a first electrode material layer and a solid electrolyte layer, the first electrode material layer is arranged on the surface of one side of the current collector, the solid electrolyte layer is arranged on the surface of one side of the first electrode material layer away from the current collector, and the solid electrolyte layer at least covers part of side edges of the first electrode material layer;

[0129] S2: providing an edge sealing portion made of an insulation adhesive on at least part of side edges of the electrode plate body to obtain a composite electrode plate, wherein the edge sealing portion at least covers part of side edges of the current collector and part of side edges of the functional layer (the specific structure of the composite electrode plate can refer to FIG. 7).

[0130] Specifically, the current collector is a stainless steel foil, and the current collector has a quadrilateral structure. The first electrode material layer is a positive active material layer, which includes positive active material, conductive agent, binder, and solid electrolyte as its components, wherein the ratio (mass ratio) of the four is 78:2:2: 18, the positive active material is LiNi09Co005Mn005O2, the conductive agent is SP (conductive carbon black), the binder is SBR (styrene butadiene rubber), and the solid electrolyte is LiioGeP2Si2. The insulation adhesive is hot melt adhesive and made of PA (polyamide). When manufacturing the composite electrode plate, the positive active material, the conductive agent, the binder and the solid electrolyte are mixed in a solvent to form a slurry. The slurry is coated on one side of the stainless steel foil and dried to form the first electrode material layer; then, the solid electrolyte layer is provided on the first electrode material layer, and the solid electrolyte layer covers four side edges of the first electrode material layer to obtain an electrode plate body with a quadrilateral structure, wherein the solid electrolyte layer is formed by coating slurry, and the material of the solid electrolyte layer is PEO (polyethylene oxide), which is a polymer solid electrolyte. Then, the insulation adhesive is provided on four side edges of the electrode plate body, so that the upper and lower surfaces of the insulation adhesive are on the same horizontal plane as the upper and lower surfaces of the electrode plate body to obtain a composite electrode plate.

[0131] A second electrode material layer is provided on the composite electrode plate. The second electrode material layer is prepared by dry filming method. The second electrode material layer is a negative active material layer, and the material of the second electrode material layer is silicon. The composite electrode plate and the second electrode material layer are subjected to hot-pressing treatment, with a hot-pressing temperature of 200°C, a hot-pressing pressure of 400Mpa, and a hot-pressing time of 60 minutes, to form a battery unit. Then, multiple battery units are stacked and connected in series, and shaped by hot-pressing. Finally, electrode tabs are led out on both sides to obtain a solid state battery cell as shown in FIG. 17.

[0132] Specifically, due to the edge sealing portion on the composite electrode plate, the edge sealing portion can block external water, oxygen, etc., protect the sulfide solid electrolyte in thepositive active material layer and the solid electrolyte layer, and improve the performance of the positive active material layer and the solid electrolyte layer. Further, the edge sealing portion can also avoid the problem of short circuit between the positive active material layer and the negative active material layer during the hot-pressing process, thereby improving the yield rate of the battery. Meanwhile, the edge sealing portion can also restrain the expansion of the positive active material layer and the solid electrolyte layer, thereby avoiding the fracture of the positive active material layer and the solid electrolyte layer due to high pressure during the hot-pressing process.

[0133] Example 4

[0134] Referring to FIGS. 9 and 18, a composite electrode plate and a solid state battery cell are prepared. The manufacturing method for the composite electrode plate includes:

[0135] SI : providing a current collector, and providing a functional layer on the surface of the current collector to obtain an electrode plate body, wherein the functional layer includes a first electrode material layer, a solid electrolyte layer and a second electrode material layer, the first electrode material layer is arranged on the surface of one side of the current collector, the solid electrolyte layer is arranged on the surface of one side of the first electrode material layer away from the current collector, and the second electrode material layer is arranged on the surface of one side of the solid electrolyte layer away from the current collector;

[0136] S2: providing an edge sealing portion made of an insulation adhesive on at least part of side edges of the electrode plate body to obtain a composite electrode plate, wherein the edge sealing portion at least covers part of side edges of the current collector and part of side edges of the functional layer (the specific structure of the composite electrode plate can refer to FIG. 9).

[0137] Specifically, the current collector is a copper aluminum composite foil, and the current collector has a quadrilateral structure. The first electrode material layer is a positive active material layer, which includes positive active material, conductive agent, binder, and solid electrolyte as its components, wherein the ratio (mass ratio) of the four is 75:2:2:21, the positive active material is LiNio.8Coo.1Mno.1O2, the conductive agent is SP (conductive carbon black), the binder is SBR (styrene butadiene rubber), and the solid electrolyte is LiePSsCl. The second electrode material layer is a negative active material layer. The second electrode material layer is prepared by dry filming method, and the material of the second electrode material layer is silicon carbon. The insulation adhesive is a two-component adhesive, with the first component being aramid, accounting for 53% by mass, and the second component being PVC (polyvinyl chloride),accounting for 47%. When manufacturing the composite electrode plate, the positive active material, the conductive agent, the binder and the solid electrolyte are mixed in a solvent to form a slurry. The slurry is coated on the aluminum foil side of the copper aluminum composite foil and dried to form the first electrode material layer; then, the solid electrolyte layer is provided on the first electrode material layer, the solid electrolyte layer is prepared by dry filming method, and the material of the solid electrolyte layer is PAN (polyacrylonitrile), which is a polymer solid electrolyte; then, the second electrode material layer is provided on the solid electrolyte layer to obtain an electrode plate body with a quadrilateral structure. Then, the insulation adhesive is provided on four side edges of the electrode plate body, so that the upper and lower surfaces of the insulation adhesive are on the same horizontal plane as the upper and lower surfaces of the electrode plate body to obtain a composite electrode plate.

[0138] The composite electrode plate is subjected to hot-pressing treatment, with a hot-pressing temperature of 150°C, a hot-pressing pressure of 200Mpa, and a hot-pressing time of 60 minutes, to form a battery unit. Then, multiple battery units are stacked and connected in series, and shaped by hot-pressing. Finally, electrode tabs are led out on both sides to obtain a solid state battery cell as shown in FIG. 18.

[0139] Specifically, due to the edge sealing portion on the composite electrode plate, the edge sealing portion can block external water, oxygen, etc., protect the sulfide solid electrolyte in the positive active material layer and the solid electrolyte layer, and improve the performance of the positive active material layer and the solid electrolyte layer. Further, the edge sealing portion can also avoid the problem of short circuit between the positive active material layer and the negative active material layer during the hot-pressing process, thereby improving the yield rate of the battery. Meanwhile, the edge sealing portion can also restrain the expansion of the positive active material layer, the negative active material layer and the solid electrolyte layer, thereby avoiding the fracture of the positive active material layer, the negative active material layer and the solid electrolyte layer due to high pressure during the hot-pressing process.

[0140] Example 5

[0141] Referring to FIGS. 13 and 19, a composite electrode plate and a solid state battery cell are prepared. The manufacturing method for the composite electrode plate includes:

[0142] SI : providing a current collector, and providing a functional layer on the surface of the current collector to obtain an electrode plate body, wherein the functional layer includes a firstelectrode material layer, a solid electrolyte layer and a second electrode material layer, the first electrode material layer is arranged on the surface of one side of the current collector, the solid electrolyte layer is arranged on the surface of one side of the first electrode material layer away from the current collector, and the second electrode material layer is arranged on the surface of one side of the current collector away from the first electrode material layer;

[0143] S2: providing an edge sealing portion made of an insulation adhesive on at least part of side edges of the electrode plate body to obtain a composite electrode plate, wherein the edge sealing portion at least covers part of side edges of the current collector and part of side edges of the functional layer (the specific structure of the composite electrode plate can refer to FIG. 13).

[0144] Specifically, the current collector is made of stainless steel foil, and the current collector has a quadrilateral structure. The first electrode material layer is a positive active material layer, which includes positive active material, conductive agent, binder, and solid electrolyte as its components, wherein the ratio (mass ratio) of the four is 80:2:2:16, the positive active material is LiFePCh, the conductive agent is SP (conductive carbon black), the binder is SBR (styrene butadiene rubber), and the solid electrolyte is LiePSsCl. The second electrode material layer is a negative active material layer. The second electrode material layer is prepared by coating slurry, and the material of the second electrode material layer is lithium titanate. The insulation adhesive is hot melt adhesive and made of PC (polycarbonate). When manufacturing the composite electrode plate, the positive active material, the conductive agent, the binder and the solid electrolyte are mixed in a solvent to form a slurry. The slurry is coated on one side of the stainless steel foil and dried to form the first electrode material layer; then, the solid electrolyte layer is provided on the first electrode material layer, the solid electrolyte layer is prepared by dry filming method, and the material of the solid electrolyte layer is sulfide solid electrolyte LiePSsCl; then, the second electrode material layer is provided on the other side of the stainless steel foil to obtain an electrode plate body with a quadrilateral structure. Then, the insulation adhesive is provided on four side edges of the electrode plate body, so that the upper and lower surfaces of the insulation adhesive are on the same horizontal plane as the upper and lower surfaces of the electrode plate body to obtain a composite electrode plate.

[0145] The composite electrode plate is subjected to hot-pressing treatment, with a hot-pressing temperature of 200°C, a hot-pressing pressure of 280Mpa, and a hot-pressing time of 45 minutes, to form a battery unit. Then, multiple battery units are stacked and connected in series, and shapedby hot-pressing. Finally, electrode tabs are led out on both sides to obtain a solid state battery cell as shown in FIG. 19.

[0146] Specifically, due to the edge sealing portion on the composite electrode plate, the edge sealing portion can block external water, oxygen, etc., protect the sulfide solid electrolyte in the positive active material layer and the solid electrolyte layer, and improve the performance of the positive active material layer and the solid electrolyte layer. Further, the edge sealing portion can also avoid the problem of short circuit between the positive active material layer and the negative active material layer during the hot-pressing process, thereby improving the yield rate of the battery. Meanwhile, the edge sealing portion can also restrain the expansion of the positive active material layer, the negative active material layer and the solid electrolyte layer, thereby avoiding the fracture of the positive active material layer, the negative active material layer and the solid electrolyte layer due to high pressure during the hot-pressing process.

[0147] The above are only the specific embodiments of the present application, but the scope of protection of the present application is not limited to this. Any technical personnel familiar with this technical field who can easily think of changes or replacements within the scope of technology disclosed in the present application should be covered within the scope of protection of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

CLAIM(S)What is claimed is:

1. A composite electrode plate, comprising an electrode plate body, wherein at least part of side edges of the electrode plate body is provided with an edge sealing portion, and the edge sealing portion is made of an insulation material; the electrode plate body comprises a current collector and a functional layer stacked with the current collector, and the edge sealing portion at least covers part of side edges of the current collector and part of side edges of the functional layer.

2. The composite electrode plate as claimed in claim 1, wherein the functional layer comprises a first electrode material layer, and the first electrode material layer is arranged on a surface of one side of the current collector; the edge sealing portion at least covers part of side edges of the first electrode material layer.

3. The composite electrode plate as claimed in claim 2, wherein the first electrode material layer is a positive active material layer or a negative active material layer.

4. The composite electrode plate as claimed in claim 2, wherein the functional layer further comprises a solid electrolyte layer, and the solid electrolyte layer is arranged on a surface of one side of the first electrode material layer away from the current collector; the edge sealing portion at least covers part of side edges of the solid electrolyte layer.

5. The composite electrode plate as claimed in claim 4, wherein the solid electrolyte layer at least covers part of the side edges of the first electrode material layer.

6. The composite electrode plate as claimed in claim 5, wherein the solid electrolyte layer comprises a main body portion and a folded edge portion extending and protruding from a side edge of the main body portion towards the current collector, the main body portion is provided on a surface of one side of the first electrode material layer away from the current collector, and the folded edge portion at least covers part of the side edges of the first electrode material layer; the edge sealing portion at least partially covers an outer side wall of the folded edge portion.

7. The composite electrode plate as claimed in claim 4, wherein the functional layer further comprises a second electrode material layer, and the second electrode material layer is arranged on a surface of one side of the solid electrolyte layer away from the current collector, or the second electrode material layer is arranged on a surface of one side of the current collector away from the first electrode material layer; the edge sealing portion at least covers part of side edges of the second electrode material layer.

8. The composite electrode plate as claimed in claim 7, wherein one of the first electrode material layer and the second electrode material layer is a positive active material layer, and the other is a negative active material layer.

9. The composite electrode plate as claimed in claim 1, wherein, along a thickness direction of the composite electrode plate, upper and lower surfaces of the edge sealing portion do not exceed upper and lower surfaces of the electrode plate body.

10. The composite electrode plate as claimed in claim 9, wherein, along the thickness direction of the composite electrode plate, the upper and lower surfaces of the edge sealing portion are respectively flush with the upper and lower surfaces of the electrode plate body.

11. The composite electrode plate as claimed in claim 1, wherein an outer side wall of the edge sealing portion is a planar structure.

12. The composite electrode plate as claimed in claim 1, wherein the edge sealing portion is provided on all the side edges of the electrode plate body, and the edge sealing portion covers all the side edges of the current collector and all the side edges of the functional layer.

13. The composite electrode plate as claimed in claim 1, wherein a material of the edge sealing portion is insulation adhesive, and the edge sealing portion is fixed to the side edge(s) of the electrode plate body by adhering.

14. A manufacturing method for the composite electrode plate as claimed in claim 1, comprising:SI : providing a current collector, and providing a functional layer on a surface of the current collector to obtain an electrode plate body;S2: providing an edge sealing portion made of an insulation material on at least part of side edges of the electrode plate body to obtain a composite electrode plate, wherein the edge sealing portion at least covers part of side edges of the current collector and part of side edges of the functional layer.

15. The manufacturing method for the composite electrode plate as claimed in claim 14, wherein in the step SI, the functional layer comprises a first electrode material layer, and the first electrode material layer is arranged on a surface of one side of the current collector; in the step S2, the edge sealing portion at least covers part of side edges of the first electrode material layer.

16. The manufacturing method for the composite electrode plate as claimed in claim 15, wherein in the step SI, the functional layer further comprises a solid electrolyte layer, and the solid electrolyte layer is arranged on a surface of one side of the first electrode material layer away from the current collector; in the step S2, the edge sealing portion also at least covers part of side edges of the solid electrolyte layer.

17. The manufacturing method for the composite electrode plate as claimed in claim 16, wherein in the step SI, the functional layer further comprises a second electrode material layer, and the second electrode material layer is arranged on a surface of one side of the solid electrolyte layer away from the current collector, or the second electrode material layer is arranged on a surface of one side of the current collector away from the first electrode material layer; in the step S2, the edge sealing portion also at least covers part of side edges of the second electrode material layer.

18. The manufacturing method for the composite electrode plate as claimed in claim 14, further comprising:S3: hot-pressing the composite electrode plate.

19. The manufacturing method for the composite electrode plate as claimed in claim 14, wherein the insulation material is an insulation adhesive, and the edge sealing portion is fixed to the side edge(s) of the electrode plate body by adhering.

20. A solid state battery, comprising multiple composite electrode plates as claimed in claim 1, wherein the multiple composite electrode plates are stacked along a thickness direction thereof.

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