Positive electrode sheet, solid-state battery, electric device and preparation method

Abstract

Provided are a positive electrode sheet, a solid-state battery, an electric device and a preparation method. The positive electrode sheet comprises a positive electrode current collector and an active film layer located on at least one side of the positive electrode current collector, wherein the active film layer comprises a positive electrode active region and a filling region located on at least part of the periphery of the positive electrode active region. The positive electrode active region comprises positive electrode active particles and a sulfide solid electrolyte, and the filling region comprises a positive electrode stabilizer. The positive electrode sheet has significantly improved air stability, and can also significantly inhibit the escape of hydrogen sulfide gas.

Description

Positive electrode sheet, solid-state battery, power-consuming device and preparation method

[0001] Related applications

[0002] This application claims priority to Chinese patent application number CN202410175721X, filed on February 7, 2024, entitled “Positive electrode sheet, all-solid-state battery, electrical device and preparation method,” the entire text of which is hereby incorporated by reference. Technical Field

[0003] The present application relates to the field of solid-state battery technology, further to the field of all-solid-state battery technology, and further to a positive electrode plate, a solid-state battery, an electrical device and a preparation method, wherein the solid-state battery further relates to an all-solid-state battery. Background Art

[0004] The statements herein merely provide background information related to the present application and do not necessarily constitute prior art.

[0005] Solid-state batteries use non-flammable solid electrolytes instead of the organic electrolytes found in traditional liquid secondary batteries, significantly improving battery safety and being considered the next generation of batteries closest to industrialization. All-solid-state batteries are batteries that use solid electrodes and solid electrolytes. These batteries use solid electrolytes instead of the liquid electrolytes found in traditional batteries, and the solid electrolyte also serves to separate the positive and negative electrodes, eliminating the need for a separator. Their advantages in safety and energy density have garnered widespread attention in recent years. Among solid electrolytes, sulfide electrolytes have attracted considerable attention due to their excellent ion conductivity. However, sulfide electrolytes are poorly air-stable and sensitive to moisture in the air. They readily absorb moisture and react, producing toxic hydrogen sulfide gas, which affects the battery's electrochemical performance, thus limiting their application.

[0006] Summary of the Invention

[0007] According to various embodiments and examples of the present application, a positive electrode plate, a solid-state battery, an electrical device, a preparation method, and applications are provided. The solid-state battery further relates to an all-solid-state battery. The positive electrode plate has a positive electrode stabilizer disposed in the blank area of ​​the overhang design, which significantly improves air stability. This structural design can also significantly inhibit the escape of hydrogen sulfide gas.

[0008] In a first aspect of the present application, a positive electrode plate is provided, which includes a positive electrode current collector and an active film layer located on at least one side of the positive electrode current collector, the active film layer including a positive electrode active area and a filling area located at least a portion of the periphery of the positive electrode active area; wherein the positive electrode active area includes positive electrode active particles and a sulfide solid electrolyte; and the filling area includes a positive electrode stabilizer.

[0009] In some embodiments, the cathode stabilizer includes at least one of a moisture absorber and a hydrogen sulfide absorber.

[0010] In some embodiments, a positive electrode sheet is provided, comprising a positive electrode current collector and an active film layer located on at least one side of the positive electrode current collector, wherein the thickness direction of the active film layer is recorded as a longitudinal direction, and the direction perpendicular to the longitudinal direction is recorded as a transverse direction;

[0011] In the transverse direction, the active membrane layer includes a positive electrode active area and a filling area located at least partially around the positive electrode active area;

[0012] The positive electrode active area includes positive electrode active particles and a positive electrode solid electrolyte, and the positive electrode solid electrolyte includes a sulfide solid electrolyte; the filling area includes a positive electrode stabilizer, and the positive electrode stabilizer includes at least one of a moisture absorber and a hydrogen sulfide absorber.

[0013] For existing solid-state batteries (which may be all-solid-state batteries) that employ an overhang structure, the width of the positive electrode active material layer in the positive electrode layer is smaller than the width of the negative electrode active material layer in the negative electrode layer. The positive electrode plate provided in the first aspect of the present application has a corresponding blank area on the positive electrode side filled with a stabilizer (referred to as a positive electrode stabilizer) that is beneficial for improving the air stability of the positive electrode material. The positive electrode stabilizer includes at least one of a moisture absorber and a hydrogen sulfide absorber. During the preparation of the positive electrode sheet and the assembly of the battery, on the one hand, the filling area can play a certain role in physically isolating moisture in the air from the positive electrode active area; on the other hand, the moisture absorber can reduce or avoid the contact probability between the sulfide electrolyte and moisture, effectively reduce or delay the possibility of the sulfide solid electrolyte reacting with moisture in the air during the positive electrode sheet manufacturing process, inhibit the reaction between the sulfide electrolyte and moisture in the air from the source, and reduce or avoid the generation and escape of toxic hydrogen sulfide gas. In addition, the moisture absorber can also improve the material stability in the positive electrode active area, reduce or avoid the adverse effects of moisture in the air on moisture-sensitive materials in the positive electrode active area, promote the sulfide solid electrolyte to more stably and more effectively perform its rapid ion conduction function, inhibit the increase in interfacial impedance within the positive electrode sheet, give full play to the capacity of the positive electrode active material and the ion conduction ability of the sulfide solid electrolyte, and thus help improve the cycle performance of the assembled solid-state battery (the solid-state battery can be an all-solid-state battery); on the other hand, the hydrogen sulfide absorber can absorb the toxic hydrogen sulfide gas generated by the reaction of the sulfide electrolyte with possible contact moisture, reducing or avoiding the escape of hydrogen sulfide gas.

[0014] In addition, by inhibiting the formation of hydrogen sulfide gas in the sulfide solid electrolyte, the formation of inert by-products in the sulfide solid electrolyte can also be reduced, which can inhibit the increase in impedance and thus improve the rate performance of the battery.

[0015] In addition, the positive electrode sheet can also be used in conjunction with a negative electrode sheet of the same size in the transverse direction, which helps to prevent the positive electrode sheet from shearing the negative electrode sheet during high-voltage processing, thereby helping to prevent the negative electrode sheet from breaking or falling off.

[0016] In some embodiments, the positive electrode stabilizer satisfies one or more of the following characteristics:

[0017] The weight proportion of the positive electrode stabilizer in the filling area is 30wt% to 99.5wt%, and can be optionally 45wt% to 98wt%;

[0018] In the filling area, the mass ratio of the moisture absorbent to the hydrogen sulfide absorbent is 0 to 1, and can be optionally 1:9 to 9:1;

[0019] The weight proportion of the moisture absorbent in the filling area is 0wt% to 99.5wt%, optionally 10wt% to 90wt%, and further optionally 40wt% to 60wt%;

[0020] The weight proportion of the hydrogen sulfide absorbent in the filling area is 0 wt% to 99.5 wt%, optionally 10 wt% to 90 wt%, and further optionally 40 wt% to 60 wt%.

[0021] By adjusting the weight ratio of the positive electrode stabilizer in the filling area (R0 M ), the mass ratio of moisture absorbent and hydrogen sulfide absorbent in the filling area (R H2O / H2S ), the weight ratio of moisture absorbent in the filling area (R1 H2O ) and the weight ratio of hydrogen sulfide absorbent in the filling area (R1 H2S ) can adjust the content of the positive electrode stabilizer in the positive electrode sheet, so as to better play the role of reducing or avoiding the contact probability between the sulfide electrolyte and moisture and thus reducing or avoiding the escape of hydrogen sulfide gas.

[0022] By controlling R1 H2O Within the aforementioned range, the content of the moisture absorber in the positive electrode plate can be adjusted, which is not only conducive to better reducing or avoiding the probability of contact between the sulfide electrolyte and moisture, reducing or avoiding the generation and escape of hydrogen sulfide gas, but also conducive to better enhancing the material stability of the positive electrode active area, promoting the sulfide solid electrolyte to more effectively and stably perform fast ion conduction, and is more conducive to improving the electrochemical properties of the solid-state battery (the solid-state battery can be an all-solid-state battery) assembled secondary using the positive electrode plate, such as achieving better cycle performance.

[0023] By controlling R1 H2S Within the aforementioned range, it is beneficial to better reduce or avoid the escape of hydrogen sulfide gas.

[0024] In some embodiments, the positive electrode stabilizer satisfies one or more of the following characteristics:

[0025] The positive electrode stabilizer includes the moisture absorber, and the moisture absorber includes one or more of a physical water absorbent and a chemical water absorbent;

[0026] The positive electrode stabilizer includes the hydrogen sulfide absorber, and the hydrogen sulfide absorber includes one or more of a hydrogen sulfide physical absorber and a hydrogen sulfide chemical absorber.

[0027] In some embodiments, the positive electrode stabilizer satisfies one or more of the following characteristics:

[0028] The moisture absorbent includes a physical water absorbent, which includes one or more water absorbents selected from the group consisting of silica gel, molecular sieve, metal organic framework, and porous carbon; wherein the porous carbon water absorbent includes activated carbon;

[0029] The moisture absorbent includes a chemical water absorbent, and the chemical water absorbent includes one or more of CaCl2, CaH2, anhydrous CuSO4, LiCl, FeCl3, FeO(OH), KMnO4, Na2CO3, Fe2O3, Fe(OH)3, ZnO, CuO, NiO and Al2O;

[0030] The hydrogen sulfide absorbent includes a hydrogen sulfide physical absorbent, and the hydrogen sulfide physical absorbent includes one or more hydrogen sulfide absorbents selected from activated carbon, molecular sieves, and metal organic frameworks;

[0031] The hydrogen sulfide absorbent includes a hydrogen sulfide chemical absorbent, and the hydrogen sulfide chemical absorbent includes one or more of Fe2O3, ZnO, Bi2O3, CuO and MnO.

[0032] The type of at least one of the moisture absorber and the hydrogen sulfide absorber can be flexibly selected to better reduce or prevent hydrogen sulfide gas leakage. By flexibly selecting the moisture absorber, the probability of contact between the sulfide electrolyte and moisture can be further reduced or prevented, thereby reducing or preventing hydrogen sulfide gas leakage, promoting more stable and effective functioning of the sulfide solid electrolyte, and further improving the battery's cycling performance.

[0033] In some embodiments, the positive electrode stabilizer includes a dual absorber, which refers to a substance that serves as both the moisture absorber and the hydrogen sulfide absorber.

[0034] The dual absorbent includes one or more of a dual physical absorbent and a dual chemical absorbent; the dual physical absorbent refers to a substance that absorbs water and hydrogen sulfide simultaneously based on physical action, and the dual chemical absorbent refers to a substance that absorbs water and hydrogen sulfide simultaneously based on chemical action.

[0035] In some embodiments, the positive electrode stabilizer satisfies one or more of the following characteristics:

[0036] The positive electrode stabilizer includes the dual physical absorbent, and the dual physical absorbent includes one or more of activated carbon, molecular sieve and metal organic framework;

[0037] The positive electrode stabilizer includes the dual chemical absorber, and the dual chemical absorber includes one or more of ZnO and CuO.

[0038] When the positive electrode stabilizer includes a dual absorber, it can simultaneously play the role of a moisture absorber and a hydrogen sulfide absorber, which is beneficial to more effectively reduce or avoid hydrogen sulfide escape, and improve the material and performance stabilizer of the positive electrode active area, thereby better improving the cycle performance of the battery.

[0039] In some embodiments, the positive electrode stabilizer includes the dual chemical absorbent and the dual physical absorbent, and the dual physical absorbent includes one or more of activated carbon and molecular sieve.

[0040] When one or more physical absorbents such as activated carbon and molecular sieve are used in conjunction with dual chemical absorbents, the effect of simultaneously absorbing water and hydrogen sulfide is better.

[0041] In some embodiments, the filling area further includes a first adhesive; the first adhesive includes one or more of a rubber adhesive, carboxymethyl cellulose, a polyolefin adhesive, a polyurethane adhesive, a polyacrylate adhesive, a polyacrylic resin, polyvinylidene fluoride, polytetrafluoroethylene, a vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, a vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, and a tetrafluoroethylene-hexafluoropropylene copolymer;

[0042] Wherein, the rubber adhesive comprises at least one of a fluorinated rubber adhesive and a rubber adhesive that does not contain fluorine element;

[0043] The polyacrylate adhesive includes at least one of a fluorine-containing acrylic resin and a polyacrylate adhesive that does not contain fluorine.

[0044] In some embodiments, the first binder includes one or more of styrene-butadiene rubber, nitrile rubber, hydrogenated nitrile rubber, polyacrylic resin, and polyurethane binders.

[0045] In some embodiments, the weight percentage of the first binder in the filling area is 0.5 wt % to 5 wt %, and can be optionally 2 wt % to 4 wt %.

[0046] By providing a binder in the filling area, the cohesive force between the various filling components in the filling area can be enhanced, thereby stabilizing the filling state of components such as the positive electrode stabilizer, and allowing the filling area to function more consistently and stably. Furthermore, by regulating the weight percentage of the binder in the filling area within the aforementioned range, it is further beneficial to fully utilize the aforementioned functions of the binder while also fully and persistently utilizing the functions of other components such as the positive electrode stabilizer.

[0047] In some embodiments, the filling region includes the first binder, and the positive electrode active region includes a second binder; the first binder and the second binder are of the same type.

[0048] When the filling area and the positive electrode active area use the same type of binder, it is beneficial to improve the adhesion strength of the filling area on the positive electrode current collector.

[0049] In some embodiments, the filling region further includes an insulating material.

[0050] In some embodiments, the filling area satisfies one or more of the following characteristics:

[0051] The insulating material includes one or more of an inorganic oxide insulating material, boehmite, non-woven fiber, and fibrous resin; optionally, the inorganic oxide insulating material includes one or more of Al2O3, MgO, SiO2, BaTiO3, BaCO3, Fe3O4, TiO2, Y2O3, Mn2O3, and Mn2O7;

[0052] The weight percentage of the insulating material in the filling area is less than or equal to 69wt%, and can be optionally 1wt% to 50wt%;

[0053] In the filling region, a mass ratio of the insulating material to the positive electrode stabilizer is less than or equal to 2, and may be selected from 0.5 to 1.

[0054] By placing insulating material in the filling area, on the one hand, the risk of internal short circuits can be better avoided, and on the other hand, the distribution concentration of the positive electrode stabilizer can be adjusted, which can help adjust the content of the positive electrode stabilizer in the filling area. The type of insulating material can be flexibly selected accordingly.

[0055] By adjusting one or both of the parameters of "weight proportion of insulating material in the filling area" and "mass ratio of insulating material to positive electrode stabilizer in the filling area" within the above range, it is beneficial to better avoid the risk of internal short circuit while flexibly setting an appropriate content of positive electrode stabilizer in the filling area.

[0056] In some embodiments, the positive electrode active particles include a positive electrode active body and a coating layer located on at least a portion of the surface of the positive electrode active body, the positive electrode active body includes one or more of a lithium transition metal oxide and a lithium-containing phosphate, and the coating layer includes a lithium oxygen compound.

[0057] In some embodiments, the lithium oxygen compound satisfies one or more of the following characteristics:

[0058] The lithium oxygen compound includes one or more elements selected from the group consisting of B, Nb, Zr, Si, P, Mn, Zn, Al, Fe, and Na;

[0059] The lithium oxygen compound accounts for 0.1 wt % to 5 wt % of the positive electrode active particles.

[0060] In some embodiments, the lithium oxygen compound satisfies one or more of the following characteristics:

[0061] The lithium oxygen compound includes one or more of Li3BO3, LiNbO3, Li2ZrO3, Li2SiO3, LiPO3 and Li2MnO4;

[0062] The lithium oxygen compound accounts for 0.1 wt % to 2 wt % of the positive electrode active particles.

[0063] By setting a coating layer on the surface of the positive electrode active body, it is beneficial to maintain a certain ion conductivity while physically isolating the positive electrode active body from the sulfide solid electrolyte. It can inhibit the side reactions caused by space charge when the positive electrode active body and the sulfide solid electrolyte are in contact, inhibit the decomposition of the sulfide solid electrolyte, reduce the interface impedance, and help the positive electrode active body to fully exert its capacity, and is more conducive to improving the battery cycle performance.

[0064] By adjusting the "weight proportion of the lithium oxide compound in the positive electrode active particles" within the aforementioned range, it is beneficial to achieve a higher energy density while fully exerting the improvement effect of the coating layer.

[0065] In some embodiments, the sulfide solid electrolyte includes at least one of a binary sulfide solid system and a ternary sulfide solid system;

[0066] The binary sulfide solid state system includes one or more of Li2S-P2S5, Li2S-SiS2, Li2S-GeS2 and Li2S-B2S3;

[0067] The ternary sulfide solid-state system includes one or more of an argyrodite-type sulfide electrolyte, a Li2S-MeS2-P2S5 ternary sulfide electrolyte, a lithium-germanium-phosphorus-sulfur sulfide electrolyte, a Li2S-P2S5-MS ternary sulfide electrolyte, a Li2S-P2S5-MCl ternary sulfide electrolyte and a thio-LISICON-type sulfide electrolyte; wherein Me includes one or more elements of Si, Ge, Sn and Al; and M includes one or more elements of Ge, Al, Sn, Pb, Sb, Si and As.

[0068] When a filling area is provided, the selection of a sulfide solid electrolyte does not have to be limited by the strength of its hygroscopicity. The type of sulfide solid electrolyte can be selected more flexibly based on the needs of one or more aspects such as ion conductivity, electrochemical window range, conductivity, particle size, etc.

[0069] In some embodiments, the positive electrode stabilizer includes a moisture absorber, and the positive electrode solid electrolyte further includes a halide solid electrolyte;

[0070] Optionally, the halide solid electrolyte includes lithium, halogen and X element, wherein the X element includes one or more of Y, In, Zr, Sc, Ho, Mn, Cd and Pb, and the halogen includes one or more of Cl, Br and I.

[0071] In some embodiments, the halide solid electrolyte comprises Li3X 1 Cl6、LiX 1 I4、LiX 1 I3 and Li3X 1 Br6, one or more of the halide solid electrolyte X 1 Includes one or more of Y, In, Sc, Ho, Mn, Cd and Pb.

[0072] When the positive electrode solid electrolyte also includes a halide solid electrolyte that is easy to physically absorb water, the positive electrode active material layer may face a more serious water absorption problem, and the water absorption caused by the halide solid electrolyte will further aggravate the instability of the sulfide solid electrolyte. At this time, by adopting the positive electrode plate structure design of the first aspect of the present application and providing a moisture absorber in the positive electrode stabilizer, a more significant improvement in the air stability of the positive electrode plate can be achieved. The moisture absorber can significantly reduce or avoid the absorption of water by the positive electrode active area, reduce or avoid the escape of hydrogen sulfide gas, and can more significantly improve the material stability and performance stability of the positive electrode active area (including the sulfide solid electrolyte), which is more conducive to improving the electrochemical performance of the assembled solid-state battery (the solid-state battery can be an all-solid-state battery), for example, the cycle performance of the battery can be better improved.

[0073] In some embodiments, the positive electrode active area has a first side surface and a second side surface that are opposite to each other, and the first side surface and the second side surface respectively intersect with the transverse direction;

[0074] The filling areas are respectively arranged on outer sides of opposite areas of the first side surface and the second side surface.

[0075] By setting filling areas on both lateral sides of the positive electrode active area, it is beneficial to better isolate the positive electrode active area from the contact with moisture in the air when assembling a solid-state battery (the solid-state battery can be an all-solid-state battery), thereby reducing or avoiding the escape of hydrogen sulfide gas.

[0076] In some embodiments, the first side surface and the second side surface are completely covered by the filling region.

[0077] When the filling area completely covers both sides of the positive electrode active area in the width direction, it is beneficial to better isolate the positive electrode active area from contact with moisture in the air when assembling the solid-state battery (the solid-state battery can be an all-solid-state battery), thereby reducing or avoiding the escape of hydrogen sulfide gas.

[0078] In some embodiments, in the lateral direction, the positive electrode active area is completely surrounded by the filling area.

[0079] When the filling area completely surrounds the positive electrode active area in the laterally direction, it is beneficial to better isolate the positive electrode active area from the contact with moisture in the air when assembling the solid-state battery (the solid-state battery can be an all-solid-state battery), thereby reducing or avoiding the escape of hydrogen sulfide gas.

[0080] In some embodiments, based on the projection area of ​​the filling area in the transverse direction, the width of the filling area at different positions along the outside of the positive electrode active area is greater than or equal to 0.2 mm, and can be optionally 0.2 mm to 10 mm, and can further be optionally 0.5 mm to 10 mm.

[0081] By controlling the width of the filler region outside the positive electrode active area within a certain range, it is possible to reduce or prevent contact between the positive electrode active area and moisture in the air. Furthermore, by further selecting an appropriate range, a higher energy density can be achieved. Furthermore, this width setting effectively prevents internal short circuits caused by changes in the electrode volume during battery cycling and shearing of the overhang region during charge and discharge.

[0082] In some embodiments, the volume ratio of the filling area to the positive electrode active area is greater than or equal to 0.2%, optionally 0.2% to 20%, and further optionally 0.5% to 10%.

[0083] By regulating one or both of the mass ratio and volume ratio of the filling area in the positive electrode active area within the aforementioned range, it is beneficial to reduce or avoid the contact between the positive electrode active area and moisture in the air. In addition, a higher energy density can be achieved at the same time by further selecting a suitable range.

[0084] In some embodiments, the active membrane layer has the same thickness at different lateral positions.

[0085] When the thickness of the active film layer at different lateral positions is equal, there is no height difference between the positive electrode active area and the filling area on the surface of the active film layer away from the positive electrode current collector. Therefore, when the positive electrode sheet is used in conjunction with the negative electrode sheet and subjected to high-pressure treatment, it is beneficial to avoid the positive electrode sheet shearing the negative electrode sheet, and to avoid the negative electrode sheet from breaking or falling off.

[0086] In a second aspect of the present application, a solid-state battery is provided, comprising a positive electrode layer, a solid electrolyte layer and a negative electrode layer stacked in sequence, wherein the positive electrode layer comprises the positive electrode sheet described in the first aspect of the present application.

[0087] In some embodiments, the solid-state battery is an all-solid-state battery.

[0088] In some embodiments, an all-solid-state battery is provided, comprising a positive electrode layer, a solid electrolyte layer, and a negative electrode layer stacked in sequence, wherein the positive electrode layer comprises the positive electrode sheet described in the first aspect of the present application.

[0089] In some embodiments, the positive electrode layer, the solid electrolyte layer, and the negative electrode layer have the same projection area along the longitudinal direction.

[0090] By setting the positive electrode layer, solid electrolyte layer and negative electrode layer to equal sizes in the horizontal direction and aligning them, so that the projection areas of the three along the longitudinal direction are consistent (at this time, the side surfaces of each structural layer are aligned), it is beneficial to reduce the breakage or powdering of the structural layer caused by interlayer shear during high-pressure treatment.

[0091] In a third aspect of the present application, an electrical device is provided, which includes the solid-state battery described in the second aspect of the present application.

[0092] In some embodiments, an electrical device is provided, which includes the all-solid-state battery described in the second aspect of the present application.

[0093] In the fourth aspect of the present application, a method for preparing an all-solid-state battery is provided, comprising the following steps:

[0094] Providing a substrate including a stacked solid electrolyte layer and a negative electrode layer, wherein the negative electrode layer is located on one side of the solid electrolyte layer;

[0095] The positive electrode sheet described in the first aspect of the present application is composited onto a side of the solid electrolyte layer away from the negative electrode layer to prepare a solid-state battery;

[0096] Optionally, the solid-state battery is an all-solid-state battery.

[0097] In some embodiments, a method for preparing an all-solid-state battery is provided, comprising the following steps:

[0098] Providing a substrate including a solid electrolyte layer and a negative electrode layer stacked together, wherein the negative electrode layer is located on one side of the solid electrolyte layer;

[0099] The positive electrode sheet described in the first aspect of the present application is composited onto the side of the solid electrolyte layer away from the negative electrode layer to prepare an all-solid-state battery.

[0100] The details of one or more embodiments or examples of the present application are set forth in the following drawings and description. Other features, objects, and advantages of the present application will become apparent from the description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0101] In order to better describe and illustrate the embodiments, examples or examples provided in this application, reference may be made to one or more of the accompanying drawings. The additional details or examples used to describe the accompanying drawings should not be considered as limiting the scope of the disclosed application, the currently described embodiments, examples or examples, and any of the currently understood best modes of these applications. It should also be noted that the accompanying drawings are all drawn in a simplified form and are only used to assist in the explanation of this application in a convenient and clear manner. The various dimensions of each component shown in the accompanying drawings are arbitrarily shown and may be accurate or not drawn to scale. For example, in order to make the illustrations clearer, the dimensions of the components are appropriately exaggerated in some places in the accompanying drawings. Unless otherwise specified, the components in the drawings are not drawn to scale. The drawings of this application do not limit each dimension of each component.

[0102] Also, like reference numerals are used throughout the drawings to denote like parts.

[0103] In the attached figure:

[0104] FIG1 is a schematic diagram of the structure and internal components of a positive electrode sheet according to one embodiment of the present application, showing a longitudinal cross section.

[0105] FIG2 is a schematic structural diagram of a positive electrode sheet according to an embodiment of the present application, showing a longitudinal cross section.

[0106] FIG3 is a schematic diagram of the structure and internal components of a positive electrode sheet according to an embodiment of the present application, showing a longitudinal cross section.

[0107] FIG4 is a schematic diagram of the structure and internal components of a positive electrode sheet according to an embodiment of the present application, showing a longitudinal cross section.

[0108] FIG5 is a schematic structural diagram of a positive electrode sheet according to an embodiment of the present application, showing a transverse cross section.

[0109] FIG6 is a schematic structural diagram of a positive electrode sheet according to an embodiment of the present application, showing a transverse cross section.

[0110] FIG7 is a schematic structural diagram of an all-solid-state battery cell according to an embodiment of the present application.

[0111] FIG8 is a schematic structural diagram of an all-solid-state battery cell according to an embodiment of the present application.

[0112] FIG9 is a schematic diagram of the structure of an all-solid-state battery cell according to one embodiment of the present application.

[0113] FIG10 is a schematic diagram of an all-solid-state battery cell according to an embodiment of the present application.

[0114] FIG11 is an exploded view of the all-solid-state battery cell according to one embodiment of the present application shown in FIG10 .

[0115] FIG12 is a schematic diagram of a battery module according to an embodiment of the present application.

[0116] FIG13 is a schematic diagram of a battery pack according to an embodiment of the present application.

[0117] FIG14 is an exploded view of the battery pack shown in FIG13 according to an embodiment of the present application.

[0118] FIG15 is a schematic diagram of an electrical device using an all-solid-state battery as a power source according to an embodiment of the present application.

[0119] About the figure marks: 10, positive electrode sheet; 110, positive electrode current collector; 120, positive electrode active area; 130, filling area; 121, positive electrode active particles; 122, positive electrode solid electrolyte; 131, positive electrode stabilizer; 132, first binder; 133, insulating material; 100, positive electrode layer; 200, solid electrolyte layer; 300, negative electrode layer; 310, negative electrode current collector; 320, negative electrode active material layer; Y, longitudinal direction; X1, width direction of the positive electrode active area in the transverse direction; X2, length direction of the positive electrode active area in the transverse direction; 1, battery pack; 2, upper box; 3, lower box; 4, battery module; 5, all-solid-state battery cell; 51, shell; 52, all-solid-state battery cell; 53, cover plate; 6, electrical device; 10, positive electrode sheet.

[0120] It should be understood that the dimensions of the positive electrode layer 100, positive electrode current collector 110, positive electrode active region 120, filling region 130, solid electrolyte layer 200, negative electrode layer 300, negative electrode current collector 310, and negative electrode active material layer 320 in the drawings do not represent actual dimensions. The shapes and sizes of the positive electrode active particles 121, positive electrode solid electrolyte 122, positive electrode stabilizer 131, first binder 132, and insulating material 133 shown in the drawings do not represent or limit the shapes and sizes of the actual particles, and the illustrated quantities of the components do not represent or limit the actual quantities or ratios. DETAILED DESCRIPTION

[0121] Below, some embodiments of the positive electrode sheet, solid-state battery, all-solid-state battery, electrical device and preparation method of the present application are described in detail with appropriate reference to the accompanying drawings. However, there may be cases where unnecessary detailed descriptions are omitted. For example, there are cases where detailed descriptions of well-known matters and repeated descriptions of actually the same structure are omitted. This is to avoid the following description from becoming unnecessarily lengthy and to facilitate the understanding of those skilled in the art. In addition, the drawings and the following description are provided for those skilled in the art to fully understand the present application and are not intended to limit the subject matter described in the claims.

[0122] " scope " disclosed in the present application can be limited in the form of lower limit and upper limit, and given range is limited by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of special range. The scope limited in this way can be to include end value or not include end value, and any end value can be included or not included independently, and can be arbitrarily combined, that is, any lower limit can form a scope with any upper limit combination. For example, if the scope of 60-120 and 80-110 is listed for specific parameters, it is understood that the scope of 60-110 and 80-120 is also expected. In addition, if minimum range values ​​1 and 2 are listed, and if maximum range values ​​3,4 and 5 are also listed, then the following scope can all be expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In the present application, unless otherwise specified, numerical range " ab " represents the abbreviation of any real number combination between a and b, wherein a and b are all real numbers. For example, the numerical range "0-5" indicates that all real numbers between "0-5" are listed herein, and "0-5" is merely an abbreviation for these numerical combinations. Furthermore, when a parameter is expressed as an integer ≥ 2, this is equivalent to listing the parameter as, for example, the integers 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, and so on. For example, when a parameter is expressed as an integer selected from "2-10", this is equivalent to listing the integers 2, 3, 4, 5, 6, 7, 8, 9, and 10.

[0123] In this application, unless otherwise specified, "about" means within a reasonable range above or below the number. The fluctuation range may vary depending on the type and value of the number. For example, a range of ±10%, ±5%, ±2%, ±1%, etc. may be allowed. For example, taking "about 20°C" and its approximate value of ±1°C as an example, approximate values ​​such as 19°C and 19.5°C within the approximate range of "about 20°C" should also be included in the range indicated by "about 20°C".

[0124] In this application, unless otherwise specified, reference to a "numerical value" includes the number itself and its reasonable approximations. The definition of the "numerical value" may apply to discrete numerical points as well as to the endpoints of a numerical range. In this application, whenever a numerical value or a numerical range is involved, unless otherwise specified, it should be understood that the numerical value covers its reasonable approximations, and the numerical range covers the reasonable approximations of the two endpoints. Those skilled in the art will understand that the acceptable fluctuation range of the relevant approximations can be included in the definition of the numerical value or the numerical range. In this application, unless otherwise specified, "N1" may be reasonably understood as "about N1", and "N1-N2" may be reasonably understood as "about N1 to about N2", wherein N1 and N2 are two unequal numerical values. For example, in some cases, due to one or more factors such as reasonable deviations allowed in the art, instrument control accuracy, etc., it is reasonable to include the approximate values ​​within the approximate range into the range defined by the numerical range; for example, "the temperature is 20°C to 30°C" can be understood as "about 20°C to about 30°C"; further, taking the endpoint "20°C" and its approximate number is ±1°C as an example, the approximate values ​​of 19°C, 19.5°C, etc. within the approximate range of "about 20°C" should also be included in the range indicated by 20°C to 30°C. As a non-limiting example, the percentage content "10%" can be reasonably understood as "about 10%". As another non-limiting example, the percentage content "2% to 10%" can be reasonably understood as "about 2% to about 10%". As another non-limiting example, the percentage content "0%" at least includes "none" and can also include the situation of "below the detection limit".

[0125] In this application, references to "multiple," "multiple," "multiple," "several," and the like, unless otherwise specified, refer to a quantity greater than or equal to two. For example, "one or more" means one or ≥ (greater than or equal to) two. It is understood that references to "any number" of items refer to any suitable combination of multiple items, i.e., any combination of "any number" of items that is not in conflict and that enables the implementation of this application.

[0126] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0127] References to "embodiments" herein mean that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment or implementation of the present application. The appearance of such phrases in various locations in the specification does not necessarily refer to the same embodiment, nor does it necessarily refer to independent or alternative embodiments that are mutually exclusive with other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments. References to "implementations" herein have a similar understanding.

[0128] Those skilled in the art will appreciate that, in the methods of each embodiment or embodiment, the order in which each step is written does not mean a strict order of execution and constitutes any limitation to the implementation process, and the detailed order of execution of each step should be determined by its function and possible inherent logic. Unless otherwise specified, all steps of the present application can be performed in sequence, or can be performed randomly, or can preferably be performed in sequence. For example, method M includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed in sequence, or steps (b) and (a) performed in sequence. For example, method M may also include step (c), indicating that step (c) can be added to method M in any order, for example, method M may include steps (a), (b) and (c), or steps (a), (c) and (b), or steps (c), (a) and (b), etc.

[0129] In this application, open technical features or technical solutions described with words such as "contain," "include," and "includes" do not exclude additional members beyond the listed members unless otherwise specified, and can be regarded as providing both closed features or solutions consisting of the listed members and open features or solutions that include additional members beyond the listed members. For example, if A includes a1, a2, and a3, it may or may not include additional members unless otherwise specified. This can be regarded as providing both the feature or solution of "A consists of a1, a2, and a3" or "A is selected from a1, a2, and a3," and the feature or solution of "A includes not only a1, a2, and a3, but also other members."

[0130] In this application, unless otherwise specified, A (such as B) means that B is a non-limiting example of A, and it can be understood that A is not limited to B.

[0131] In this application, "optionally," "optional," and "optional" mean optional, that is, they refer to either option selected from the two parallel options of "yes" or "no." If multiple "options" appear in a technical solution, unless otherwise specified and there are no contradictions or mutual constraints, each "optional" is independent. Unless otherwise specified, the descriptions "optionally include," "optionally include," etc. in this application, using "optionally include" as an example, mean "may include or not include."

[0132] In this application, unless otherwise specified, the features or solutions corresponding to "and / or" include any one of two or more relevant listed items, and also include any and all combinations of the relevant listed items, wherein any and all combinations include any two relevant listed items, any more relevant listed items, or a combination of all relevant listed items. For example, "A and / or B" means a group consisting of A, B, and "a combination of A and B." Among them, "including A and / or B" can mean "including A, including B, and including A and B", and can also mean "including A, including B, or including A and B", which can be appropriately understood according to the sentence in which it is used.

[0133] As used herein, "combination thereof", "any combination thereof", "any combination thereof" and the like include all suitable combinations of any two or more of the listed items.

[0134] Herein, the word “suitable” in “suitable combination”, “suitable method”, “any suitable method”, etc., shall be based on the technical solution that can implement the present application.

[0135] Herein, the terms "preferred," "better," "more preferable," "suitable," "comparatively better," and "preferable" are used solely to describe preferred implementations or examples and should not be construed as limiting the scope of protection of this application. If multiple "preferred" terms appear in a technical solution, each "preferred" term is considered independent unless otherwise specified and there are no contradictions or mutual constraints.

[0136] In this application, "further", "further", "particularly", "for example", "such as", "example", "for example", etc. are used for descriptive purposes to indicate differences in content, but should not be understood as limiting the scope of protection of this application.

[0137] In this application, the terms "first," "second," "third," "fourth," etc. in "the first aspect," "the second aspect," "the third aspect," "the fourth aspect," etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or quantity, nor should they be understood as implicitly indicating the importance or quantity of the indicated technical features. Furthermore, "first," "second," "third," "fourth," etc. serve only as non-exhaustive enumeration and description, and should be understood not to constitute a closed-ended limitation on quantity.

[0138] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may refer to a relative horizontal positional relationship, or may simply refer to an attachment relationship without limiting the relative horizontal positional relationship.

[0139] In this application, the term "room temperature" generally refers to 4°C to 35°C, and may refer to 20°C ± 5°C. In some embodiments or examples of this application, room temperature refers to 20°C to 30°C.

[0140] In this application, when referring to a data range, if the unit is followed only by the right endpoint, it means that the units of the left and right endpoints are the same. For example, "3~5h" or "3-5h" both mean that the units of the left endpoint "3" and the right endpoint "5" are both hours, and both have the same meaning as "3h~5h". Similarly, descriptions of other parameters such as temperature and size are to be understood in the same manner.

[0141] The weight or mass of the relevant components mentioned in the embodiments or examples of the present application can not only refer to the content of each component, but also represent the proportional relationship of weight or mass between each component. Therefore, as long as the content of the relevant components in accordance with the embodiments or examples of the present application is proportionally enlarged or reduced, it is within the scope described in the present application. Further, the mass involved in the embodiments or examples of the present application can be mass units known to the chemical industry such as micrograms (μg), milligrams (mg), grams (g), kilograms (kg). Unless otherwise specified, the mass ratio is numerically equal to the corresponding weight ratio, such as the mass of substance A is m1, and the weight is W1, the mass of substance B is m2, and the weight is W2, then the mass ratio m1 / m2 of the two is numerically equal to the corresponding weight ratio W1 / W2.

[0142] In this application, unless otherwise specified, wt% represents weight percentage by weight and is numerically equivalent to the corresponding mass percentage by mass. In this application, when a weight percentage is represented by "0", it has the same meaning as "0wt%" and can be used interchangeably.

[0143] The units of parameters involved in this application, unless otherwise specified, are nm for nanometers, μm for micrometers, V for volts, mPa·s for millipascals·seconds, and mg / cm 2 Expressed in milligrams per square centimeter, g / cm 2 Indicates grams per square centimeter, g / cm 3 represents grams per cubic centimeter and ℃ represents degrees Celsius.

[0144] In this application, "greater than or equal to", "greater than or equal to", and "≥" have the same meaning and can be used interchangeably; "less than or equal to", "less than or equal to", and "≤" have the same meaning and can be used interchangeably; "greater than" can be equivalently expressed as ">", and "less than" can be equivalently expressed as "<". In this application, unless otherwise specified, "greater than or equal to" and "≥" can be regarded as providing two solutions of "greater than" and "equal to". In this application, unless otherwise specified, "less than or equal to" and "≤" can be regarded as providing two solutions of "less than" and "equal to".

[0145] In this application, exemplary descriptions such as "in some embodiments (or examples)" and "in one embodiment (or example)" may include but are not limited to the following meanings: these solutions can be combined with other solutions in a suitable manner to form new technical solutions.

[0146] In this application, unless otherwise specified, the "solid-state battery" provided in this application refers to a battery in which the electrolyte in the battery includes a solid electrolyte; generally, a solid-state battery includes a positive electrode layer, a solid electrolyte layer and a negative electrode layer. During the charge and discharge process of the battery, active ions are embedded and released back and forth between the positive electrode layer and the negative electrode layer. The solid electrolyte layer plays the role of conducting ions between the positive electrode layer and the negative electrode layer, and can also isolate the positive electrode layer from the negative electrode layer to prevent the positive and negative electrodes from short-circuiting. Therefore, the isolation membrane in the traditional lithium-ion battery can be omitted in the solid-state battery. The solid-state battery uses a non-flammable solid electrolyte to replace the organic electrolyte in the traditional liquid lithium-ion battery, which greatly improves the safety of the battery. In addition to improving safety, solid-state batteries can better adapt to high-energy-density positive and negative electrode materials and reduce the weight of the system, which is conducive to taking into account the improvement of energy density.

[0147] In this application, unless otherwise specified, the "all-solid-state battery" provided in this application refers to a battery in which the electrolyte in the battery adopts a solid electrolyte; generally, the all-solid-state battery includes a positive electrode layer, a solid electrolyte layer and a negative electrode layer. During the charge and discharge process of the battery, active ions are embedded and released back and forth between the positive electrode layer and the negative electrode layer. The solid electrolyte layer plays the role of conducting ions between the positive electrode layer and the negative electrode layer, and can also isolate the positive electrode layer from the negative electrode layer to prevent the positive and negative electrodes from short-circuiting. Therefore, the isolation membrane used in traditional lithium-ion batteries can be omitted in the all-solid-state battery.

[0148] In this application, unless otherwise specified, "solid electrolyte" refers to an electrolyte material or substance that exists in a solid form during the storage and preparation of a solid-state battery, as well as during the operation of the solid-state battery. It is understood that the solid electrolyte exists in a solid form, including but not limited to, at room temperature.

[0149] In this application, unless otherwise specified, the electrode layer is a functional layer containing active materials, which can be a positive electrode layer or a negative electrode layer. The "active material" in the electrode layer refers to a substance that can reversibly embed and release active ions. Unless otherwise specified, "negative electrode active material" refers to a substance used in the negative electrode layer that can reversibly embed and release active ions; "positive electrode active material" refers to a substance used in the positive electrode layer that can reversibly release and embed active ions. When the solid-state battery or the all-solid-state battery is charged, the active ions are released from the positive electrode and embedded in the negative electrode through the solid electrolyte layer; and when the solid-state battery or the all-solid-state battery is discharged, the active ions are released from the negative electrode and embedded in the positive electrode. There is no special limitation on the active ions, and they are non-restrictive. The active ions in the solid-state battery can be lithium ions, in which case it corresponds to a lithium-ion solid-state battery; the active ions in the all-solid-state battery can be lithium ions, in which case it corresponds to a lithium-ion all-solid-state battery.

[0150] In this application, "electrode active material", "electrode active substance", "active material" and "active substance" have the same meaning and can be used interchangeably; "positive electrode active substance" and "positive electrode active material" have the same meaning and can be used interchangeably; "negative electrode active substance" and "negative electrode active material" have the same meaning and can be used interchangeably. "Positive electrode active substance" and "positive electrode active material" have the same meaning and can be used interchangeably; "negative electrode active substance" and "negative electrode active material" have the same meaning and can be used interchangeably.

[0151] Regarding the positive electrode in solid-state batteries, for example, in all-solid-state batteries, a solid electrolyte is typically added to promote lithium ion conduction. Sulfide electrolytes have attracted considerable attention as solid electrolyte materials due to their excellent ion conductivity. However, sulfide electrolytes have poor air stability and are sensitive to moisture in the air. They easily absorb and react with moisture, producing toxic hydrogen sulfide gas. During the preparation of the positive electrode, exposure to moisture in the air is unavoidable. This air instability of the sulfide electrolyte can lead to the release of highly toxic hydrogen sulfide gas during the preparation and assembly of the positive electrode in all-solid-state batteries, hindering practical application and industrial production. Furthermore, the sulfide solid electrolyte decomposes after reacting with any moisture, impairing its ion conductivity and increasing the interfacial impedance between the positive electrode active particles and the solid electrolyte particles in the positive electrode, affecting the electrochemical performance of the assembled all-solid-state battery and impairing its cycling performance.

[0152] For example, the reaction between a sulfide solid electrolyte and water is as follows:

[0153] Existing research on the structure of all-solid-state batteries usually adopts the overhang structure design of traditional lithium-ion batteries. That is, based on the projection along the stacking direction of the various structural layers of the all-solid-state battery, the area of ​​the positive electrode active material layer is made smaller than that of the negative electrode active material layer. When the electrode sheets are subjected to high pressure treatment, this size difference will cause the relatively smaller positive electrode sheet to shear the negative electrode sheet, which can easily cause the negative electrode sheet to break or lose powder.

[0154] In a first aspect of the present application, a positive electrode plate is provided, wherein a positive electrode stabilizer is provided in a positive electrode blank area of ​​an overhang structure.

[0155] In some embodiments, a positive electrode plate is provided, which includes a positive electrode current collector and an active film layer located on at least one side of the positive electrode current collector, the active film layer including a positive electrode active area and a filling area located at least a portion of the periphery of the positive electrode active area; wherein the positive electrode active area includes positive electrode active particles and a sulfide solid electrolyte; and the filling area includes a positive electrode stabilizer.

[0156] In some embodiments, the cathode stabilizer includes at least one of a moisture absorber and a hydrogen sulfide absorber.

[0157] In some embodiments, a positive electrode sheet is provided, wherein a positive electrode stabilizer is disposed in a positive electrode blank area of ​​an overhang structure, and the positive electrode stabilizer includes at least one of a moisture absorber and a hydrogen sulfide absorber.

[0158] The positive electrode plate and solid-state battery (the solid-state battery can be an all-solid-state battery) provided in this application cleverly utilize the traditional overhang structural design, and fill the blank area of ​​the positive electrode plate with a stabilizer that is beneficial to improving the air stability of the positive electrode material, so that the positive electrode plate has significantly improved air stability. This structural design can also significantly inhibit the escape of hydrogen sulfide gas.

[0159] In some embodiments, a positive electrode sheet is provided, comprising a positive electrode current collector and an active film layer located on at least one side of the positive electrode current collector, wherein the thickness direction of the active film layer is referred to as a longitudinal direction, and the direction perpendicular to the longitudinal direction is referred to as a transverse direction;

[0160] In the transverse direction, the active film layer includes a positive electrode active area and a filling area located at least partially around the positive electrode active area;

[0161] The positive electrode active area includes positive electrode active particles and a positive electrode solid electrolyte, and the positive electrode solid electrolyte includes a sulfide solid electrolyte; the filling area includes a positive electrode stabilizer, and the positive electrode stabilizer includes at least one of a moisture absorber and a hydrogen sulfide absorber.

[0162] In this application, unless otherwise specified, the "thickness direction of the active film layer" is referred to as the longitudinal direction (see the Y direction in Figures 1-4), and the direction perpendicular to the longitudinal direction is referred to as the transverse direction. Generally speaking, the thickness direction of the positive electrode sheet is consistent with the thickness direction of the active film layer and the thickness direction of the positive electrode active region.

[0163] In this application, unless otherwise specified, “positive electrode active particles” refer to particles containing positive electrode active materials, which have the ability to reversibly release and embed active ions.

[0164] In this application, unless otherwise specified, "positive electrode stabilizer" refers to an agent that can improve the air stability of the positive electrode material. Unless otherwise specified, the positive electrode stabilizer includes at least one of a moisture absorber and a hydrogen sulfide absorber. The positive electrode stabilizer may include only a moisture absorber, or only a hydrogen sulfide absorber, or may include both a moisture absorber and a hydrogen sulfide absorber. Regarding the "absorption" in the moisture absorber, it may be based on at least one of a physical effect and a chemical effect. As long as it can play the role of binding, fixing or eliminating moisture, it is within the meaning of the moisture absorber in this application. Regarding the "absorption" in the hydrogen sulfide absorber, it may be based on at least one of a physical effect and a chemical effect. As long as it can play the role of binding, fixing or eliminating hydrogen sulfide gas, it is within the meaning of the hydrogen sulfide absorber in this application. When the moisture absorber and the hydrogen sulfide absorber exist at the same time, they may be the same substance or different substances, that is, the positive electrode stabilizer is allowed to play the dual role of a moisture absorber and a hydrogen sulfide absorber at the same time.

[0165] The positive electrode plate provided in the first aspect of the present application has a stabilizer (referred to as a positive electrode stabilizer) filled in the corresponding blank area on the positive electrode side, which is beneficial to improving the air stability of the positive electrode material. The positive electrode stabilizer includes at least one of a moisture absorber and a hydrogen sulfide absorber. In the process of preparing the positive electrode plate and assembling the battery, on the one hand, the filling area can play a certain role in physically isolating the moisture in the air from the positive electrode active area; on the other hand, the moisture absorber can reduce or avoid the contact probability between the sulfide electrolyte and moisture, effectively reduce or delay the possibility of the sulfide solid electrolyte reacting with moisture in the air during the positive electrode plate manufacturing process, inhibit the reaction between the sulfide electrolyte and moisture in the air from the source, reduce or avoid the generation and escape of hydrogen sulfide toxic gas, and in addition, the moisture absorber can also improve the material stability in the positive electrode active area, reduce or avoid moisture in the air. It has an adverse effect on moisture-sensitive materials in the positive electrode active area, promotes the sulfide solid electrolyte to play a more stable and effective role in rapid ion conduction, inhibits the increase in interfacial impedance in the positive electrode plate, and gives full play to the capacity of the positive electrode active material and the ion conduction ability of the sulfide solid electrolyte, which is beneficial to improve the electrochemical properties of the assembled solid-state battery (the solid-state battery can be an all-solid-state battery), for example, it can improve the cycle performance of the battery; on the other hand, the hydrogen sulfide absorber can absorb the toxic hydrogen sulfide gas generated by the reaction of the sulfide electrolyte with possible contact with moisture, thereby reducing or avoiding the escape of hydrogen sulfide gas.

[0166] In addition, by inhibiting the formation of hydrogen sulfide gas in the sulfide solid electrolyte, the formation of inert by-products in the sulfide solid electrolyte can also be reduced, which can inhibit the increase in impedance and thus improve the rate performance of the battery.

[0167] In addition, the positive electrode sheet can also be used in conjunction with a negative electrode sheet of the same size in the transverse direction, which helps to prevent the positive electrode sheet from shearing the negative electrode sheet during high-voltage processing, thereby helping to prevent the negative electrode sheet from breaking or falling off.

[0168] In this application, unless otherwise specified, the positive electrode plate sample can be obtained from a solid-state battery (the solid-state battery can be an all-solid-state battery) in the following manner: the battery can be disassembled to obtain the positive electrode active area sample and the filling area sample of the electrode plate, and the chemical composition in the positive electrode active area and the filling area can be further analyzed by the following method: the nano-spatial dynamic resolution and layer-by-layer cutting technology of FIB-SEM are used to reconstruct the three-dimensional structure of the sample, and the EDS element energy spectrum analysis is used in combination to obtain the distribution and proportion of each element, and finally the composition and size and other parameters of each part of the structure of the positive electrode plate are obtained through software quantitative analysis.

[0169] In this application, unless otherwise specified, the types and contents of substances in the positive electrode active region (including but not limited to positive electrode active particles and positive electrode solid electrolyte) and substances in the filling region (including but not limited to positive electrode stabilizers) in the active film layer of the positive electrode plate can be detected by the following methods: The structure and composition analysis of the active film layer can be tested and analyzed by focused electron beam (FIB) technology, scanning electron microscopy (SEM) and elemental analysis technology, for example, it can be obtained by combining cryo-focused electron beam (FIB) continuous sectioning, cross-sectional SEM morphology observation, energy dispersive spectroscopy (EDS) elemental spectrum and three-dimensional reconstruction analysis software analysis. For example, a cryo-focused ion beam (FIB) is used to finely slice the sample layer by layer along the transverse direction at different thickness positions (the minimum scale can be nanometer-level thin slices), and separate different layers of samples at different thickness positions. Scanning electron microscopy (SEM) testing can also be used to analyze the morphology, structure and element distribution of each layer of the cross section under FIB continuous sectioning. Combined with three-dimensional structure reconstruction software, the three-dimensional structure of the sample can be reconstructed to estimate the mass and / or volume of different regions of the sample to be tested. As a non-limiting example, the above parameters may be tested and analyzed using a FEI Scios 2HiVac device.

[0170] In addition, the types and contents of the chemical components in the positive electrode active region and the filling region, including but not limited to the positive electrode stabilizer and the first binder described below, the insulating material, the positive electrode active particles, the positive electrode active body, the coating layer in the positive electrode active particles, etc., can also be tested and analyzed using other suitable methods among the chemical composition detection means, such as X-ray diffraction (XRD), inductively coupled plasma spectrometry (ICP), gas chromatography-mass spectrometry (GC-MS), Fourier transform infrared spectrometry (FT-IR), Raman spectroscopy (Raman), etc. Without limitation, the material components of the coating layers of different positive electrode active particles can be detected and analyzed using elemental analysis methods such as XRD and ICP, and the binder (first binder or second binder) can be analyzed using FT-IR and Raman methods. In addition, the area size of the filling region can be analyzed using methods such as SEM and FIB.

[0171] In this application, the weight ratio of the positive electrode stabilizer in the filling area can be recorded as R0 M The mass ratio of moisture absorbent to hydrogen sulfide absorbent in the filling area can be recorded as R H2O / H2S The weight ratio of the moisture absorbent in the filling area can be recorded as R1 H2O The weight ratio of hydrogen sulfide absorbent in the filling area can be recorded as R1 H2S For the positive electrode stabilizer that can play the dual role of moisture absorber and hydrogen sulfide absorber, calculate R H2O / H2S 、R1 H2O and R1 H2SWhen the same substance is used as a moisture absorber and a hydrogen sulfide absorber, the same substance can be counted repeatedly. For example, when the positive electrode stabilizer is only one substance and plays the dual role of moisture absorber and hydrogen sulfide absorber, then R H2O / H2S is 1, further when R0 M When it is 95wt%, R1 H2O and R1 H2S are all 95 wt %, refer to Examples 16-19, etc. When there is more than one positive electrode stabilizer, and all of them can play the dual role of moisture absorber and hydrogen sulfide absorber, similarly, R H2O / H2S is 1, and R0 M 、R1 H2O and R1 H2S The values ​​are equal, please refer to Examples 27-28, etc.

[0172] In some embodiments, the weight ratio of the positive electrode stabilizer in the filling region (R0 M ) satisfies 0wt% <R0 M ≤99.5wt%, optionally 30wt% to 99.5wt%, further optionally 45wt% to 98wt%, further optionally 49wt% to 98wt%. The weight proportion of the positive electrode stabilizer in the filling area can also be any of the following weight proportions: 5wt%, 10wt%, 15wt%, 20wt%, 25wt%, 30wt%, 35wt%, 40wt%, 45wt%, 49wt%, 50wt%, 55wt%, 60wt%, 65wt%, 70wt%, 75wt%, 80wt%, 85wt%, 90wt%, 95wt%, 98wt%, 99wt%, 99.5wt%, etc. The weight proportion of the positive electrode stabilizer in the filling area can be selected from the interval consisting of any two of the foregoing weight proportions.

[0173] In some embodiments, in the filling area, the mass ratio of the moisture absorbent to the hydrogen sulfide absorbent (R H2O / H2S ) is 0-1, and can be optionally 1:9 to 9:1 (also equivalent to 1 / 9 to 9), and can also be any of the following mass ratios or an interval consisting of any two of the following mass ratios: 0, 0.05, 0.1, 1 / 9, 0.15, 0.2, 0.25, 0.3, 0.33, 1 / 3, 0.4, 0.5, 0.6, 0.75, 0.8, 0.9, 1, 1.05, 1.1, 1.2, 1.25, 1.3, 1.35, 1.4, 1.45, 1.5, 1.6, 1.75, 1.8, 2, 2.25, 2.4, 2.5, 3, 3.5, 3.6, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, etc.

[0174] In this application, "numerical ratios" may be described in the form of ratios, percentages, or numerical values ​​unless otherwise specified. For example, "mass ratio is 9:1" and "mass ratio is 9" have the same meaning and can be used interchangeably. For another example, "volume ratio is 0.1," "volume ratio is 1:10," and "volume ratio is 10%" have the same meaning and can be used interchangeably.

[0175] In some embodiments, the weight ratio of the moisture absorbent in the filling area (R1 H2O ) is 0wt% to 99.5wt%, optionally 10wt% to 90wt%, further optionally 30wt% to 70wt%, and further optionally 40wt% to 60wt%. The weight proportion of the moisture absorbent in the filling area can also be any of the following weight proportions or an interval consisting of any two of the following weight proportions: 0wt%, 1wt%, 2wt%, 4wt%, 5wt%, 6wt%, 8wt%, 10wt%, 15wt%, 20wt%, 25wt%, 30wt%, 35wt%, 40wt%, 45wt%, 50wt%, 55wt%, 60wt%, 65wt%, 70wt%, 75wt%, 80wt%, 85wt%, 90wt%, 95wt%, 98wt%, 99wt%, 99.5wt%, etc.

[0176] In some embodiments, the weight ratio of the hydrogen sulfide absorbent in the filling area (R1 H2S ) is 0wt% to 99.5wt%, optionally 10wt% to 90wt%, further optionally 30wt% to 70wt%, and further optionally 40wt% to 60wt%. The weight proportion of the hydrogen sulfide absorbent in the filling area can also be any of the following weight proportions or an interval consisting of any two of the following weight proportions: 0wt%, 1wt%, 2wt%, 4wt%, 5wt%, 6wt%, 8wt%, 10wt%, 15wt%, 20wt%, 25wt%, 30wt%, 35wt%, 40wt%, 45wt%, 50wt%, 55wt%, 60wt%, 65wt%, 70wt%, 75wt%, 80wt%, 85wt%, 90wt%, 95wt%, 98wt%, 99wt%, 99.5wt%, etc.

[0177] By adjusting the weight ratio of the positive electrode stabilizer in the filling area (R0 M ), the mass ratio of moisture absorbent and hydrogen sulfide absorbent in the filling area (R H2O / H2S ), the weight ratio of moisture absorbent in the filling area (R1 H2O ) and the weight ratio of hydrogen sulfide absorbent in the filling area (R1 H2S) can adjust the content of the positive electrode stabilizer in the positive electrode sheet, so as to better play the role of reducing or avoiding the contact probability between the sulfide electrolyte and moisture and thus reducing or avoiding the escape of hydrogen sulfide gas.

[0178] It should be noted that some positive electrode stabilizers can act as moisture absorbers and hydrogen sulfide absorbers at the same time, so R1 H2O With R1 H2S The sum of the M .

[0179] By controlling R1 H2O Within the aforementioned range, the content of the moisture absorber in the positive electrode plate can be adjusted, which is not only conducive to better reducing or avoiding the probability of contact between the sulfide electrolyte and moisture, reducing or avoiding the generation and escape of hydrogen sulfide gas, but also conducive to better enhancing the material stability of the positive electrode active area, promoting the sulfide solid electrolyte to more effectively and stably perform fast ion conduction, and is more conducive to improving the electrochemical properties of the solid-state battery (the solid-state battery can be an all-solid-state battery) assembled secondary using the positive electrode plate, such as achieving better cycle performance.

[0180] By controlling R1 H2S Within the aforementioned range, it is beneficial to better reduce or avoid the escape of hydrogen sulfide gas.

[0181] In some embodiments, the positive electrode stabilizer includes a moisture absorbent. Without limitation, the moisture absorbent may include one or more of a physical moisture absorbent and a chemical moisture absorbent. In some embodiments, the moisture absorbent may include, but is not limited to, a physical moisture absorbent. Non-limiting examples of physical moisture absorbents may include one or more moisture absorbents of silica gel, molecular sieve moisture absorbents, metal organic frameworks, and porous carbon, and the moisture absorbent of porous carbon includes activated carbon. In some embodiments, the moisture absorbent may include, but is not limited to, a chemical moisture absorbent. Non-limiting examples of chemical moisture absorbents may include, but are not limited to, one or more of CaCl2, CaH2, anhydrous CuSO4, lithium chloride (LiCl), FeCl3, FeO(OH), KMnO4, Na2CO3, Fe2O3, Fe(OH)3, ZnO, CuO, NiO, Al2O, etc.

[0182] In some embodiments, the positive electrode stabilizer includes a hydrogen sulfide absorber. Without limitation, the hydrogen sulfide absorber may include one or more of a hydrogen sulfide physical absorber and a hydrogen sulfide chemical absorber. In some embodiments, the hydrogen sulfide absorber includes but is not limited to a hydrogen sulfide physical absorber. Non-limiting examples of hydrogen sulfide physical absorbers may include one or more hydrogen sulfide absorbers from activated carbon, molecular sieves, and metal organic frameworks. In some embodiments, the hydrogen sulfide absorber may include but is not limited to a hydrogen sulfide chemical absorber. Non-limiting examples of hydrogen sulfide chemical absorbers may include one or more of Fe2O3, ZnO, Bi2O3, CuO, MnO, etc.

[0183] The type of at least one of the moisture absorber and the hydrogen sulfide absorber can be flexibly selected to better reduce or prevent hydrogen sulfide gas leakage. By flexibly selecting the moisture absorber, the probability of contact between the sulfide electrolyte and moisture can be further reduced or prevented, thereby reducing or preventing hydrogen sulfide gas leakage, promoting more stable and effective functioning of the sulfide solid electrolyte, and further improving the battery's cycling performance.

[0184] Those skilled in the art can understand the mechanism of action of the above-mentioned various moisture absorbers from the relevant technical fields based on the description in this application, and can use different types of moisture absorbers in combination as needed, and can also use moisture absorbers with different mechanisms of action in combination.

[0185] Those skilled in the art can understand the mechanisms of action of the various hydrogen sulfide absorbers described above from the relevant technical fields, based on the disclosures in this application. This allows for the combined use of different types of hydrogen sulfide absorbers, and also allows for the combined use of hydrogen sulfide absorbers with different mechanisms of action. For example, the hydrogen sulfide chemical absorbent ZnO can eliminate hydrogen sulfide gas using the following chemical reaction: ZnO + H₂S → ZnS + H₂O. However, this reaction produces water, so it can be used in conjunction with a moisture absorbent.

[0186] In some embodiments, the positive electrode stabilizer includes a dual absorbent, which refers to a substance that acts as both a moisture absorbent and a hydrogen sulfide absorbent. The dual absorbent may include one or more of a dual physical absorbent and a dual chemical absorbent; a dual physical absorbent refers to a substance that absorbs moisture and hydrogen sulfide simultaneously based on a physical effect; a dual chemical absorbent refers to a substance that absorbs moisture and hydrogen sulfide simultaneously based on a chemical effect. Without limitation, the dual physical absorbent may include one or more of activated carbon, molecular sieves, and metal-organic frameworks. Without limitation, the dual chemical absorbent may include one or more of ZnO, CuO, Fe2O3, CaO, etc. In some embodiments, the dual chemical absorbent includes at least one of ZnO and CuO. In some embodiments, the dual chemical absorbent includes ZnO. Without limitation, the dual absorbent may include one or more of ZnO, CuO, activated carbon, molecular sieves, and metal-organic frameworks.

[0187] In some embodiments, the positive electrode stabilizer includes one or more of ZnO, CuO, Fe2O3, CaO, etc. Optionally, the positive electrode stabilizer includes at least one of ZnO and CuO. Further optionally, the positive electrode stabilizer includes ZnO.

[0188] When the positive electrode stabilizer includes a dual absorber, it can simultaneously play the role of a moisture absorber and a hydrogen sulfide absorber, which is beneficial to more effectively reduce or avoid hydrogen sulfide escape, and improve the material and performance stabilizer of the positive electrode active area, thereby better improving the cycle performance of the battery.

[0189] In some embodiments, the positive electrode stabilizer includes a dual absorber, and the dual absorber includes a dual physical absorber and a dual chemical absorber.

[0190] When physical absorbents are used in conjunction with dual chemical absorbents, the effect of absorbing both water and hydrogen sulfide is better.

[0191] In some embodiments, the positive electrode stabilizer includes a dual chemical absorbent and a dual physical absorbent, and the dual physical absorbent includes one or more of activated carbon and molecular sieve.

[0192] When the positive electrode stabilizer contains only dual absorbers, which means that the types and weights of the moisture absorber and the hydrogen sulfide absorber are exactly the same, then R H2O / H2S Equal to 1, R1 H2O 、R1 H2S and R0 M The values ​​of the three are equal.

[0193] When one or more physical absorbents such as activated carbon and molecular sieve are used in conjunction with dual chemical absorbents, the effect of simultaneously absorbing water and hydrogen sulfide is better.

[0194] In some embodiments, the filling region includes a binder (referred to as a first binder). In this case, the filling region includes at least a positive electrode stabilizer and a first binder. Non-limitingly, the first binder may include, but is not limited to, one or more of a rubber binder, carboxymethyl cellulose, a polyolefin binder, a polyurethane binder, a polyacrylate binder, a polyacrylic resin, polyvinylidene fluoride, polytetrafluoroethylene, a vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, a vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, and a tetrafluoroethylene-hexafluoropropylene copolymer.

[0195] Without limitation, the rubber adhesive may include at least one of fluorinated rubber or rubber adhesives that do not contain fluorine. In some embodiments, the rubber adhesive includes fluorinated rubber, and may further be a fluorinated rubber adhesive. In other embodiments, the rubber adhesive includes a rubber adhesive that does not contain fluorine. Without limitation, the polyacrylate adhesive may include at least one of a fluorinated acrylic resin or a polyacrylate adhesive that does not contain fluorine. In some embodiments, the polyacrylate adhesive includes a fluorinated acrylic resin. In some embodiments, the polyacrylate adhesive includes a polyacrylate adhesive that does not contain fluorine. Non-limiting examples of the first adhesive may include one or more of styrene-butadiene rubber, nitrile rubber, hydrogenated nitrile rubber, polyacrylic resin, polyurethane adhesive, etc.

[0196] In this application, unless otherwise specified, the "binder" in the filling area is referred to as the first binder, which refers to a binder that can at least bind the components of the filling area.

[0197] In some embodiments, the weight percentage of the first binder in the filling area is 0.5wt% to 5wt%, optionally 1wt% to 4wt%, further optionally 2wt% to 4wt%, and can also be any of the following percentages or an interval consisting of any two of the following percentages: 0.5wt%, 0.6wt%, 0.8wt%, 1wt%, 1.2wt%, 1.5wt%, 1.6wt%, 1.8wt%, 2wt%, 2.5wt%, 3wt%, 3.5wt%, 4wt%, 4.5wt%, 5wt%, etc.

[0198] In some embodiments, the positive electrode active area includes a binder (which may be referred to as a second binder). The types of the first binder and the second binder may be the same or different. The type of the second binder may refer to the description of the first binder. For example, the second binder may include, but is not limited to, one or more of a rubber binder, carboxymethyl cellulose, a polyolefin binder, a polyurethane binder, a polyacrylate binder, a polyacrylic resin, polyvinylidene fluoride, polytetrafluoroethylene, a vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, a vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, a tetrafluoroethylene-hexafluoropropylene copolymer, and the like. Non-limiting examples of the second binder may include one or more of styrene-butadiene rubber, nitrile rubber, hydrogenated nitrile rubber, polyacrylic resin, polyurethane binder, and the like. As one of the non-limiting examples, the second binder may include one or more of a rubber binder, polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), a vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, a vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, a tetrafluoroethylene-hexafluoropropylene copolymer, and a fluorine-containing acrylate resin. In a non-limiting manner, the weight percentage of the second binder in the positive electrode active area can be 0-10wt%, further can be 0-8wt%, further can be 0.1wt%-5wt%, further can be 1wt%-5wt%, based on the total weight of the positive electrode active area. The weight percentage of the second binder in the positive electrode active area can also be 0.2wt%-5wt%, 0.5wt%-5wt%, 0.1wt%-3wt%, 0.3wt%-3wt%, 1wt%-3wt%, etc.

[0199] In the present application, the first binder located in the filling region and the second binder located in the positive electrode active region, when both are present, may be the same or different.

[0200] In some embodiments, the filling region includes a first binder, the positive electrode active region includes a second binder, and the first binder and the second binder are of the same type.

[0201] When the filling area and the positive electrode active area use the same type of binder, it is beneficial to improve the adhesion strength of the filling area on the positive electrode current collector.

[0202] The filling area may or may not include insulating material. The weight proportion of the insulating material in the filling area may be 0 wt % to 69 wt %, optionally 0 wt % to 66 wt %, further optionally 0 wt % to 60 wt %, further optionally 0 wt % to 50 wt %, but is not limited thereto.

[0203] In some embodiments, the filling region includes an insulating material. In this case, the filling region includes at least a positive electrode stabilizer and an insulating material. In some embodiments, the filling region includes a positive electrode stabilizer, a first binder, and an insulating material.

[0204] Without limitation, the insulating material may include one or more of an inorganic oxide insulating material, boehmite, non-woven fabric fiber, and fibrous resin. Without limitation, the inorganic oxide insulating material may include one or more of Al2O3, MgO, SiO2, BaTiO3, BaCO3, Fe3O4, TiO2, Y2O3, Mn2O3, and Mn2O7.

[0205] By placing insulating material in the filling area, on the one hand, the risk of internal short circuits can be better avoided, and on the other hand, the distribution concentration of the positive electrode stabilizer can be adjusted, which can help adjust the content of the positive electrode stabilizer in the filling area. The type of insulating material can be flexibly selected accordingly.

[0206] In some embodiments, the weight proportion of the insulating material in the filling area is 0 wt % to 50 wt %, further optionally 1 wt % to 50 wt %, further optionally 1 wt % to 10 wt %, further optionally 3 wt % to 7 wt %.

[0207] Without limitation, the weight proportion of the insulating material in the filling area can be any of the following suitable weight proportions or a suitable range selected from any two of the following weight proportions: 0wt%, 1wt%, 2wt%, 4wt%, 5wt%, 6wt%, 8wt%, 10wt%, 15wt%, 20wt%, 25wt%, 30wt%, 35wt%, 40wt%, 45wt%, 50wt%, 55wt%, 60wt%, 66wt%, 69wt%, etc.

[0208] In some embodiments, the mass ratio of the insulating material to the positive electrode stabilizer is less than or equal to 2, and may be 0 to 2, further 0.5 to 2, further 0.5 to 1, or 1 to 1.5. Without limitation, the mass ratio of the insulating material to the positive electrode stabilizer may be any of the following ratios or an interval selected from any of the following ratios: 0, 0.05, 0.1, 1 / 9, 0.15, 0.2, 0.25, 0.3, 0.33, 1 / 3, 0.4, 0.5, 0.6, 0.75, 0.8, 0.9, 1, 1.05, 1.1, 1.2, 1.25, 1.3, 1.35, 1.4, 1.45, 1.5, 1.6, 1.75, 1.8, 2, etc.

[0209] By adjusting one or both of the parameters of "weight proportion of insulating material in the filling area" and "mass ratio of insulating material to positive electrode stabilizer in the filling area" within the above range, it is beneficial to better avoid the risk of internal short circuit while flexibly setting an appropriate content of positive electrode stabilizer in the filling area.

[0210] In some embodiments, the positive electrode active particles include at least a positive electrode active body, which may or may not include a coating layer on at least a portion of the surface of the positive electrode active body. As defined above, the positive electrode active body includes a positive electrode active material.

[0211] Without limitation, the weight percentage of the positive electrode active material in the positive electrode active body can be 95wt% to 100wt%, or can be any of the following percentages or an interval consisting of any two of the following percentages: 95wt%, 96wt%, 97wt%, 98wt%, 99wt%, 100wt%, etc.

[0212] When the positive electrode active particles include a coating layer, the coating layer may include, but is not limited to, a lithium oxide compound. The weight percentage of the coating layer in the positive electrode active particles may be 0 wt% to 5 wt%, optionally 0.1 wt% to 5 wt%, further optionally 0.5 wt% to 5 wt%, further 0.1 wt% to 2 wt%, further 0.5 wt% to 2 wt%, or any one or two of the following weight percentages: 0 wt%, 0.1 wt%, 0.2 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.8 wt%, 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 4 wt%, 4.5 wt%, 5 wt%, etc.

[0213] In this application, unless otherwise specified, "positive electrode active particles" may or may not include a coating layer. When a coating layer is included, the coating layer is located on at least a portion of the surface of the positive electrode active body. Without limitation, the weight percentage of the coating layer in the positive electrode active particles can be 0.1wt% to 5wt%, optionally 0.5wt% to 5wt%, or 0.1wt% to 2wt%, and reference may also be made to the above definition. Without limitation, the thickness of the coating layer can be 0.1nm to 50nm, optionally 0.5nm to 10nm. It can also be any of the following thicknesses or a range consisting of any two of the following thicknesses: 0.1nm, 0.2nm, 0.4nm, 0.5nm, 0.6nm, 0.8nm, 1nm, 2nm, 3nm, 4nm, 5nm, 6nm, 7nm, 8nm, 9nm, 10nm, 12nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, etc.

[0214] Without limitation, the weight percentage of the positive electrode active material in the positive electrode active particles can be 95wt% to 100wt%, or can be any of the following percentages or an interval consisting of any two of the following percentages: 95wt%, 96wt%, 97wt%, 98wt%, 99wt%, 100wt%, etc.

[0215] The structure (e.g., presence or absence of a coating) and chemical composition of the positive electrode active particles can be detected using the aforementioned methods, such as, but not limited to, X-ray diffraction (XRD), inductively coupled plasma spectrometry (ICP), and other analytical methods. Any method that can be used to detect the structure and chemical composition of the positive electrode active particles can be used in this application.

[0216] In this application, unless otherwise specified, the D v 50 can be 1μm~15μm, optionally 5μm~15μm, further optionally 5μm~12μm, or can be any of the following particle sizes or an interval consisting of the following two particle sizes: 1μm, 2μm, 3μm, 4μm, 5μm, 6μm, 8μm, 10μm, 12μm, 15μm, etc.

[0217] In some embodiments, the D of the particles in the coating layer is v 50 is less than or equal to 1μm.

[0218] In some embodiments, the D of the lithium oxygen compound in the coating layer is v 50 is less than or equal to 1μm.

[0219] In the context of this application, the volume cumulative distribution particle size D can be used v N (where N represents any value selected from 0 to 100) is used to characterize the particle size of the material, which refers to the particle size corresponding to when the cumulative volume distribution percentage of the material reaches N%. The particle size is less than or equal to D v The volume percentage of N is N%. v N can be obtained from the volume cumulative distribution curve of the material particle size. If there is no other explanation, the volume cumulative distribution curve starts from zero from the small particle size side. v 50 is used as an example. In this application, if there is no other description, D v 50 refers to the particle size corresponding to when the cumulative volume distribution percentage of the material reaches 50%. This parameter indicates that the particle size of 50% of the material volume is less than or equal to D v 50, and 50% of the volume of the material has a particle size larger than D v 50. Those skilled in the art will understand that vThe particle size distribution of the particle size distribution is defined as 50, and can be measured using instruments and methods known in the art. For example, it can be conveniently measured using a laser particle size analyzer, such as the Mastersizer 2000E laser particle size analyzer or the LS-909 laser particle size analyzer (Omega), manufactured by Malvern Instruments Ltd., UK.

[0220] Without limitation, the positive electrode active material in the positive electrode active particles can be any known battery positive electrode active material in the art. As non-limiting examples, the positive electrode active material can include one or more of the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. Furthermore, the positive electrode active material can include one or more of the following materials: lithium-containing phosphates with an olivine structure, lithium transition metal oxides, and their respective modified compounds. However, this application is not limited to these materials; other conventional materials that can be used as battery positive electrode active materials can also be used. These positive electrode active materials can be used singly or in combination. Examples of lithium transition metal oxides include, but are not limited to, one or more of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, and their modified compounds. Non-limiting examples of lithium-containing phosphates with an olivine structure include, but are not limited to, one or more of lithium iron phosphate, a composite material of lithium iron phosphate and carbon, lithium manganese phosphate, a composite material of lithium manganese phosphate and carbon, lithium iron manganese phosphate, and a composite material of lithium iron manganese phosphate and carbon. Non-limiting examples of lithium cobalt oxides may include LiCoO2; non-limiting examples of lithium nickel oxides may include LiNiO2; non-limiting examples of lithium manganese oxides may include LiMnO2, LiMn2O4, etc.; non-limiting examples of lithium nickel cobalt manganese oxides may include LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also referred to as NCM 333 ), LiNi 0.5 Co 0.2 Mn 0.3 O2 (also referred to as NCM 523 ), LiNi 0.5 Co 0.25 Mn 0.25 O2 (also referred to as NCM 211 ), LiNi 0.6 Co 0.2 Mn 0.2 O2 (also referred to as NCM 622 ), LiNi 0.8 Co 0.1 Mn 0.1O2 (also referred to as NCM 811 ) etc. Non-limiting examples of lithium nickel cobalt aluminum oxide may include LiNi 0.80 Co 0.15 Al 0.05 O2. An example of lithium iron phosphate is LiFePO4 (also referred to as LFP). An example of lithium manganese phosphate is LiMnPO4.

[0221] Taking a solid-state battery in which active ions include lithium ions as an example, and further taking an all-solid-state battery in which active ions include lithium ions as an example, it is understandable that the all-solid-state battery will be accompanied by lithium (Li) deintercalation and consumption during the charge and discharge process, and the Li content in the positive electrode layer is different when the battery is discharged to different states. In the exemplary description of the positive electrode active material in this application, unless otherwise specified, the Li content can be the initial state of the material or the non-initial state after the charge and discharge cycle. The positive electrode active material is applied to the positive electrode layer in the all-solid-state battery system. After the charge and discharge cycle, the Li content in the positive electrode active material contained in the positive electrode layer usually changes. Among them, the Li content can be measured using atomic molar content, but is not limited to this. Regarding "the Li content is the initial state of the material", the initial state of the material refers to the state before being placed in the positive electrode layer. It is understandable that new materials or new substances obtained by appropriate modification based on the listed positive electrode active materials are also within the scope of positive electrode active materials. The aforementioned appropriate modification refers to an acceptable modification method for the positive electrode active material, and a non-limiting example is coating modification. In the exemplary descriptions of the positive electrode active material in this application, the oxygen (O) content is generally a theoretical value. Lattice oxygen release will cause the atomic molar content of oxygen to change, and the actual O content will fluctuate. The O content can be measured by atomic molar content, but is not limited to this.

[0222] In some embodiments, the positive electrode active particles include a positive electrode active body and a coating layer located on at least a portion of the surface of the positive electrode active body, the positive electrode active body includes one or more of a lithium transition metal oxide and a lithium-containing phosphate, and the coating layer includes a lithium oxygen compound.

[0223] The coating layer of the positive active particles may or may not include a lithium oxygen compound.

[0224] Without limitation, the weight percentage of the lithium oxygen compound in the positive electrode active particles can be 0 wt % to 5 wt %. When the positive electrode active particles include a coating layer, and the coating layer includes a lithium oxygen compound, the weight percentage of the lithium oxygen compound in the positive electrode active particles can be 0.1 wt % to 5 wt %, further 0.5 wt % to 5 wt %, 0.1 wt % to 2 wt %, or 0.5 wt % to 2 wt %. The weight percentage of the lithium oxygen compound in the positive electrode active particles can also be any one of the following weight percentages, or any two of the following weight percentages: 0 wt %, 0.1 wt %, 0.2 wt %, 0.4 wt %, 0.5 wt %, 0.6 wt %, 0.8 wt %, 1 wt %, 1.5 wt %, 2 wt %, 2.5 wt %, 3 wt %, 4 wt %, 4.5 wt %, 5 wt %, etc.

[0225] In some embodiments, the positive electrode active particles include a positive electrode active body and a coating layer located on at least a portion of the surface of the positive electrode active body, wherein the coating layer includes a lithium oxygen compound. The weight percentage of the lithium oxygen compound in the coating layer may be 90 wt% to 100 wt%, or may be any of the following percentages, or a range consisting of any two of the following percentages: 90 wt%, 92 wt%, 94 wt%, 95 wt%, 96 wt%, 97 wt%, 98 wt%, 99 wt%, 100 wt%, etc., but is not limited thereto.

[0226] Without limitation, the lithium oxygen compound in the coating layer may include one or more elements selected from the group consisting of B, Nb, Zr, Si, P, Mn, Zn, Al, Fe, and Na. In some embodiments, the lithium oxygen compound in the coating layer may include one or more selected from the group consisting of Li3BO3, LiNbO3, Li2ZrO3, Li2SiO3, LiPO3, and Li2MnO4.

[0227] By setting a coating layer on the surface of the positive electrode active body and introducing a compound component (such as lithium oxygen compound) that is insensitive to water and has a certain ion conductivity into the coating layer, it is beneficial to maintain a certain ion conductivity while physically isolating the positive electrode active body from the sulfide solid electrolyte. It can inhibit the side reactions caused by space charge when the positive electrode active body and the sulfide solid electrolyte are in contact, inhibit the decomposition of the sulfide solid electrolyte, reduce the interface impedance, and help the positive electrode active body to fully exert its capacity, and is more conducive to improving the battery cycle performance.

[0228] In the present application, the following methods can be used to prepare positive electrode active particles provided with a coating layer: (1) According to the elemental composition and atomic stoichiometry, the positive electrode active body can be prepared by sol-gel method (Sol-Gel), atomic layer deposition (ALD), molecular layer deposition (MLD), melt coating, dry coating, hydrothermal method, coprecipitation method, spray drying method and the like; (2) According to the material composition of the coating layer, a physical coating or chemical coating method is used to form a coating layer with a certain weight percentage on the surface of the positive electrode active body. Those skilled in the art can select a suitable method to prepare the positive electrode active body and achieve surface coating according to the structure and elemental composition of the positive electrode active particles in the present application. By adjusting the amount of coating layer material input in the coating operation, the weight percentage of the coating layer in the positive electrode active particles can be controlled.

[0229] Without limitation, the weight percentage of the lithium oxygen compound in the coating layer relative to the positive electrode active particles is 0.1 wt% to 5 wt%, optionally 0.5 wt% to 5 wt%, further 0.1 wt% to 2 wt%, further 0.5 wt% to 2 wt%, and further, see the above definition. Adjusting the "weight percentage of the lithium oxygen compound relative to the positive electrode active particles" within the aforementioned range is advantageous for achieving a higher energy density while fully utilizing the improvement effect of the coating layer.

[0230] Without limitation, when the positive electrode active particles or the positive electrode active body contain lithium transition metal oxides, the lithium transition metal oxides may include lithium transition metal oxides that are well known in the art and can be used as positive electrode active materials in solid-state batteries (solid-state batteries can be all-solid-state batteries), but are not limited thereto. Examples of lithium transition metal oxides may include, but are not limited to, one or more of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, and modified compounds thereof. Examples of various lithium transition metal oxides can be found above. For example, non-limiting examples of lithium nickel cobalt manganese oxides may include NCM 333 、NCM 523 、NCM 211 、NCM 622 、NCM 811 Non-limiting examples of lithium nickel cobalt aluminum oxide may include LiNi 0.80 Co 0.15 Al 0.05 O2.

[0231] In some embodiments, the positive electrode active body includes a lithium-containing phosphate. The types of lithium-containing phosphates are defined above. This helps reduce the chemical potential difference between the positive electrode active particles and the electrolyte material in the positive electrode active region, thereby reducing interfacial side reactions, lowering interfacial impedance, improving material stability, and enhancing cycling performance.

[0232] In some embodiments, the sulfide solid electrolyte includes at least one of a binary sulfide solid system and a ternary sulfide solid system. Without limitation, the binary sulfide solid system may include one or more of Li2S-P2S5, Li2S-SiS2, Li2S-GeS2, and Li2S-B2S3. Without limitation, the ternary sulfide solid system may include one or more of an argyrodite-type sulfide electrolyte, a Li2S-MeS2-P2S5 ternary sulfide electrolyte, a lithium-germanium-phosphorus-sulfur sulfide electrolyte, a Li2S-P2S5-MS ternary sulfide electrolyte, a Li2S-P2S5-MCl ternary sulfide electrolyte, and a thio-LISICON-type sulfide electrolyte; wherein Me may include one or more elements of Si, Ge, Sn, and Al; and M may include one or more elements of Ge, Al, Sn, Pb, Sb, Si, and As. In some embodiments, Me is selected from one or more elements of Si, Ge, Sn, and Al. In some embodiments, M is selected from one or more elements of Ge, Al, Sn, Pb, Sb, Si, and As.

[0233] When a filling area is provided, the selection of a sulfide solid electrolyte does not have to be limited by the strength of its hygroscopicity. The type of sulfide solid electrolyte can be selected more flexibly based on the needs of one or more aspects such as ion conductivity, electrochemical window range, conductivity, particle size, etc.

[0234] In some embodiments, the positive electrode stabilizer includes a moisture absorber, and the positive electrode solid electrolyte further includes a halide solid electrolyte. Without limitation, the halide solid electrolyte may include lithium, a halogen, and an X element, wherein the X element may include one or more of Y, In, Zr, Sc, Ho, Mn, Cd, Pd, etc., or may be selected from one or more of the aforementioned elements. Without limitation, the halogen may include one or more of Cl, Br, and I, or may be selected from one or more of the aforementioned elements. In some embodiments, the halogen is selected from one or both of Cl and Br, and may further be Cl or Br.

[0235] In some embodiments, the halide solid electrolyte may include Li3X 1 Cl6、LiX 1 I4、LiX 1 I3、Li3X 1 Br6 etc., optionally, X in the halide solid electrolyte 1 It may include one or more of Y, In, Zr, Sc, Ho, Mn, Cd, Pd, etc., and may also be selected from one or more of the aforementioned elements.

[0236] When the positive electrode solid electrolyte also includes a halide solid electrolyte that is easy to physically absorb water, the positive electrode active material layer may face a more serious water absorption problem, and the water absorption caused by the halide solid electrolyte will further aggravate the instability of the hydrogen sulfide solid electrolyte. At this time, by adopting the positive electrode plate structure design of the first aspect of the present application and providing a moisture absorber in the positive electrode stabilizer, a more significant improvement in the air stability of the positive electrode plate can be achieved. The moisture absorber can significantly reduce or avoid the absorption of water by the positive electrode active area, reduce or avoid the escape of hydrogen sulfide gas, and can more significantly improve the material stability and performance stability of the positive electrode active area (including the sulfide solid electrolyte), which is more conducive to improving the electrochemical performance of the assembled solid-state battery (the solid-state battery can be an all-solid-state battery), for example, it can better improve the cycle performance of the battery.

[0237] In some embodiments, the positive electrode active region has a first side surface and a second side surface that are opposite to each other, and the first side surface and the second side surface respectively intersect with the transverse direction;

[0238] Filling areas are respectively provided on the outer sides of the opposing areas of the first side surface and the second side surface;

[0239] An example of this can be seen in Figure 5. In Figure 5, for example, along the width direction X1 of the positive electrode active area, the positive electrode active area is provided with filler regions on both sides; along the length direction X2 of the positive electrode active area, the positive electrode active area is not provided with filler regions on both sides. Taking a wound structure as an example, the X2 direction can correspond to the winding direction when assembling a solid-state battery (the solid-state battery can be an all-solid-state battery). In this case, the lengthwise sides of the positive electrode active area of ​​a single layer can be free from air.

[0240] By setting filling areas on both lateral sides of the positive electrode active area, it is beneficial to better isolate the positive electrode active area from the contact with moisture in the air when assembling a solid-state battery (the solid-state battery can be an all-solid-state battery), thereby reducing or avoiding the escape of hydrogen sulfide gas.

[0241] In some embodiments, a positive electrode sheet includes a positive electrode current collector 110 and an active membrane layer located on one side of the positive electrode current collector 110. The active membrane layer includes a positive electrode active region 120. The positive electrode active region 120 has a first side surface and a second side surface that are opposed to each other, and the first side surface and the second side surface intersect with the transverse direction. A filling region 130 is provided outside the opposing regions of the first side surface and the second side surface. The positive electrode active region 120 includes positive electrode active particles 121 and a positive electrode solid electrolyte 122, and the filling region 130 includes a positive electrode stabilizer 131. An example of this can be seen in Figure 1. In Figure 1, the first side surface and the second side surface are illustratively perpendicular to the transverse direction, that is, parallel to the longitudinal direction Y. The positive electrode solid electrolyte includes a sulfide solid electrolyte; and the positive electrode stabilizer includes at least one of a moisture absorber and a hydrogen sulfide absorber.

[0242] In some embodiments, based on the positive electrode sheet shown in FIG1 , the filling region 130 further includes a first binder 132 , an example of which can be seen in FIG3 .

[0243] In some embodiments, based on the positive electrode sheet shown in FIG1 , the filling region 130 further includes a first binder 132 and an insulating material 133 , an example of which can be seen in FIG4 .

[0244] In some embodiments, a positive electrode sheet includes a positive electrode current collector 110 and active membrane layers located on both sides of the positive electrode current collector 110. The active membrane layers on either side independently include a positive electrode active region 120. The positive electrode active region 120 on either side independently has two opposing side surfaces, with the two side surfaces on one side being designated as a first side surface and a second side surface, and the two side surfaces on the other side being designated as a third side surface and a fourth side surface. The first side surface, the second side surface, the third side surface, and the fourth side surface intersect with a transverse direction, respectively. A filling region 130 is provided outside the opposing regions of the first and second side surfaces, respectively, and a filling region 130 is provided outside the opposing regions of the third and fourth side surfaces, respectively. An example of this is shown in FIG2 . In FIG2 , the first, second, third, and fourth side surfaces are illustratively perpendicular to the transverse direction, i.e., parallel to the longitudinal direction Y. The positive electrode active region includes positive electrode active particles and a positive electrode solid electrolyte, wherein the positive electrode solid electrolyte includes a sulfide solid electrolyte; the filling region includes a positive electrode stabilizer, which includes at least one of a moisture absorber and a hydrogen sulfide absorber.

[0245] In some embodiments, the first side and the second side are completely covered by the filling region.

[0246] When the filling area completely covers both sides of the positive electrode active area in the width direction, it is beneficial to better isolate the positive electrode active area from contact with moisture in the air when assembling the solid-state battery (the solid-state battery can be an all-solid-state battery), thereby reducing or avoiding the escape of hydrogen sulfide gas.

[0247] In some embodiments, the positive electrode active area is completely surrounded by the filling area in the transverse direction. An example of this is shown in FIG6 .

[0248] When the filling area completely surrounds the positive electrode active area in the laterally direction, it is beneficial to better isolate the positive electrode active area from the contact with moisture in the air when assembling the solid-state battery (the solid-state battery can be an all-solid-state battery), thereby reducing or avoiding the escape of hydrogen sulfide gas.

[0249] In some embodiments, based on the horizontal projection area of ​​the filling area, the width of the filling area at different positions along the outside of the positive electrode active area is greater than or equal to 0.2 mm, and can be selected from 0.2 mm to 10 mm, further selected from 0.25 mm to 10 mm, and further selected from 0.5 mm to 10 mm. It can also be any of the following widths or an interval consisting of any two of the following widths: 0.2 mm, 0.25 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.8 mm, 1 mm, 1.2 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.8 mm, 2 mm, 2.5 mm, 3 mm, 4 mm, 5 mm, 6 mm, 8 mm, 10 mm (corresponding to 1 cm), etc.

[0250] By controlling the width of the filler region outside the positive electrode active area within a certain range, it is possible to reduce or prevent contact between the positive electrode active area and moisture in the air. Furthermore, by further selecting an appropriate range, a higher energy density can be achieved. Furthermore, this width setting effectively prevents internal short circuits caused by changes in the electrode volume during battery cycling and shearing of the overhang region during charge and discharge.

[0251] In some embodiments, the volume ratio of the filling area relative to the positive electrode active area is greater than or equal to 0.2%, and can be optionally 0.2% to 20%, further optionally 0.5% to 10%, and further optionally 1% to 10%. It can also be any of the following percentages or an interval consisting of any two of the following percentages: 0.2%, 0.4%, 0.5%, 0.6%, 0.8%, 1%, 1.2%, 1.4%, 1.6%, 1.8%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 6%, 6.5%, 7%, 7.5%, 8%, 9%, 10%, etc., and can also be a suitable range among the following: 0.5% to 20%, 0.2% to 10%, 3% to 7%, etc.

[0252] By regulating one or both of the mass ratio and volume ratio of the filling area in the positive electrode active area within the aforementioned range, it is beneficial to reduce or avoid the contact between the positive electrode active area and moisture in the air. In addition, a higher energy density can be achieved at the same time by further selecting a suitable range.

[0253] In some embodiments, the thickness of the active membrane layer is equal at different lateral locations.

[0254] When the thickness of the active film layer at different lateral positions is equal, there is no height difference between the positive electrode active area and the filling area on the surface of the active film layer away from the positive electrode current collector. Therefore, when the positive electrode sheet is used in conjunction with the negative electrode sheet and subjected to high-pressure treatment, it is beneficial to avoid the positive electrode sheet shearing the negative electrode sheet, and to avoid the negative electrode sheet from breaking or falling off.

[0255] Without limitation, the thickness of the active film layer, the positive electrode active area or the filling area on a single side of the positive electrode current collector can be 30μm to 200μm, optionally 60μm to 130μm, or any of the following thicknesses or an interval consisting of any two of the following thicknesses: 30μm, 40μm, 50μm, 60μm, 80μm, 100μm, 120μm, 130μm, 140μm, 150μm, 160μm, 180μm, 200μm, etc.; it can also be any of the following ranges: 40μm to 150μm, 40μm to 130μm, 40μm to 120μm, 50μm to 150μm, 50μm to 130μm, 50μm to 120μm, 60μm to 150μm, 60μm to 120μm, etc.

[0256] In a non-limiting manner, the weight percentage of the positive electrode active particles in the positive electrode active region may be ≥80 wt %, and further may be ≥90 wt %.

[0257] In some embodiments, the positive electrode active area includes a conductive agent (which may be referred to as a positive electrode conductive agent). As a non-limiting example, the positive electrode conductive agent may be a carbon conductive agent. Non-limitingly, the positive electrode carbon conductive agent may include one or more of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene and carbon nanofibers. Non-limitingly, the weight percentage of the positive electrode conductive agent in the positive electrode active area may be 0 to 10 wt%, further 0 to 8 wt%, further 0 to 5 wt%, further 0.1 wt% to 3 wt%, based on the total weight of the positive electrode active area. The weight percentage of the positive electrode conductive agent in the positive electrode active area may also be 0.2 wt% to 5 wt%, 0.5 wt% to 5 wt%, 0.1 wt% to 3 wt%, and the like.

[0258] As a non-limiting example, the positive electrode current collector has two surfaces facing away from each other in its thickness direction, and the active film layer is disposed on either or both of the two facing surfaces of the positive electrode current collector.

[0259] In some embodiments, the positive electrode current collector may be a metal foil or a composite current collector. For example, aluminum foil may be used as the metal foil. In the positive electrode current collector, the composite current collector may include a polymer material base layer and a metal layer formed on at least one surface of the polymer material base layer. In the positive electrode current collector, the composite current collector may be obtained by forming a metal material on a polymer material substrate. In the positive electrode current collector, non-limiting examples of the metal material may include at least one of aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy. In the positive electrode current collector, non-limiting examples of the polymer material substrate may include one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.

[0260] The positive electrode sheet can be prepared by a dry process or a wet process. For example, a dry process can be used to press the positive electrode sheet into a film. Another example is a wet process that can be used to coat the positive electrode sheet into a film.

[0261] In some embodiments, the positive electrode active area can be compounded with the positive electrode current collector in the following manner: the components used to prepare the positive electrode active area, such as positive electrode active particles, positive electrode solid electrolyte, second binder, positive electrode conductive agent and other optional components are dry mixed, and then the mixed material is heated, pressurized and kneaded into a mass material, which is hot rolled to form a self-supporting positive electrode active sheet, and the self-supporting positive electrode active sheet is hot rolled to compound with the positive electrode current collector. The self-supporting positive electrode active sheet can be compounded on at least one side (one side or two sides) of the positive electrode current collector to obtain a substrate including the positive electrode active area. Non-limitingly, a double planetary mixer can be used for dry mixing. Non-limitingly, an internal mixer can be used for heating, pressurizing and kneading. Non-limitingly, the temperature for hot rolling can be 75°C to 85°C, and further such as 78°C, 80°C, 82°C, etc. The method of assembling solid-state batteries (solid-state batteries can be all-solid-state batteries) using positive electrode sheets can be suitable for industrial mass production.

[0262] In the present application, the width of the positive electrode active area (refer to the X1 direction) can be 50mm~500mm, but is not limited to this. For example, it can also be an interval consisting of any one or any two of the following widths: 50mm, 100mm, 200mm, 300mm, 400mm, 500mm, etc.

[0263] In some embodiments, a substrate including a positive electrode active region can be prepared by dispersing the components used to prepare the positive electrode active region, such as the positive electrode active particles, the positive electrode solid electrolyte, the second binder, the positive electrode conductive agent, and other optional components, in an organic solvent to form a positive electrode slurry. Furthermore, the positive electrode slurry is coated on at least one surface of a positive electrode current collector. After drying and cold pressing, the positive electrode active region is obtained, thereby obtaining a substrate including the positive electrode active region. The cold pressing can be performed using a cold rolling mill. The organic solvent in the positive electrode slurry can include one or two of p-xylene, trimethylbenzene, butyl butyrate, heptane, and can further include p-xylene. The positive electrode slurry can be coated on a single surface of the positive electrode current collector or on both surfaces of the positive electrode current collector. The solids content of the positive electrode slurry can be 40 wt% to 80 wt%. The viscosity of the positive electrode slurry at room temperature can be adjusted to 5000 mPa·s to 25000 mPa·s. The compaction density of the positive electrode can be 3.0g / cm 3 ~3.6g / cm 3 , optional 3.3g / cm 3 ~3.5g / cm 3 .

[0264] The term "compacted density" as used in this application has a well-known meaning in the art and is one of the reference indicators of material energy density. In this application, unless otherwise specified, the compacted density of an electrode plate refers to the ratio of the mass of the electrode active material layer to its volume. The compacted density of a positive electrode plate refers to the ratio of the mass of the positive electrode active area to its volume, and the compacted density of a negative electrode plate refers to the ratio of the mass of the negative electrode active material layer to its volume.

[0265] Without limitation, the material of the filling area can be set in the target area on the positive electrode current collector by coating. Without limitation, the positive electrode stabilizer, the first binder and optional other components (such as insulating materials) can be mixed with an organic solvent to form a stabilizer slurry, and then an appropriate amount of the stabilizer slurry is applied to the target area, and a filling area can be formed after drying and cold pressing, wherein the cold pressing can achieve densification. The solid content of the stabilizer slurry can be 40wt% to 80wt%. The type of organic solvent in the stabilizer slurry can include one or two of p-xylene, trimethylbenzene, butyl butyrate, heptane, etc., and can further be p-xylene.

[0266] In the present application, the cold pressing process for preparing the positive electrode active area and the cold pressing process for preparing the filling area can be implemented simultaneously using the same process: the structural layer formed by coating and drying the positive electrode slurry and the structural layer formed by coating and drying the stabilizer slurry can be cold pressed together, thereby obtaining the positive electrode active area and the filling area at the same time. At this time, the positive electrode active area and the filling area have high consistency in the thickness direction, and the surface of the active film layer in the positive electrode sheet is smoother as a whole.

[0267] Another aspect of the present application provides the use of the aforementioned positive electrode sheet in the preparation of a solid-state battery.

[0268] In a second aspect of the present application, a solid-state battery is provided, which includes a positive electrode layer, a solid electrolyte layer and a negative electrode layer stacked in sequence, wherein the positive electrode layer includes the positive electrode sheet described in the first aspect of the present application.

[0269] In some embodiments, the solid-state battery is an all-solid-state battery.

[0270] In some embodiments, an all-solid-state battery is provided, comprising a positive electrode layer, a solid electrolyte layer, and a negative electrode layer stacked in sequence, wherein the positive electrode layer comprises the positive electrode sheet described in the first aspect of the present application.

[0271] Unless otherwise specified, the solid-state battery provided in this application is a solid-state secondary battery.

[0272] Unless otherwise specified, the all-solid-state battery provided in this application is an all-solid-state secondary battery.

[0273] In the present application, the all-solid-state battery includes a solid-state battery cell, and the solid-state battery cell includes the positive electrode plate described in the first aspect of the present application.

[0274] In this application, unless otherwise specified, a "solid-state battery cell" refers to a basic unit that can realize the mutual conversion of chemical energy and electrical energy, and its components are all solid. In some embodiments, the solid-state battery cell can be an all-solid-state battery cell.

[0275] In the present application, the all-solid-state battery includes an all-solid-state battery cell, and the all-solid-state battery cell includes the positive electrode sheet described in the first aspect of the present application.

[0276] In this application, unless otherwise specified, "all-solid-state battery cells" refer to basic units that can achieve mutual conversion between chemical energy and electrical energy, and whose components are all solid. In this case, the electrolyte in the battery is all solid electrolyte solid battery cells. In this case, the positive electrode layer, negative electrode layer and electrolyte are all made of solid materials, and the battery cell does not contain liquid electrolyte. Therefore, it can be called an "all-solid-state battery cell."

[0277] Without limitation, a solid-state battery cell (which may be an all-solid-state battery cell) may include a positive electrode layer, a solid electrolyte layer, and a negative electrode layer, wherein the solid electrolyte layer is located between the positive electrode layer and the negative electrode layer. During the charge and discharge process of the battery, active ions are embedded and extracted back and forth between the positive electrode layer and the negative electrode layer. The solid electrolyte layer acts as an ion conductor between the positive electrode layer and the negative electrode layer, and can also isolate the positive electrode layer from the negative electrode layer to prevent a short circuit between the positive and negative electrodes.

[0278] In some embodiments, the projection areas of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer along the longitudinal direction are consistent.

[0279] By setting the positive electrode layer, solid electrolyte layer and negative electrode layer to equal sizes in the horizontal direction and aligning them, so that the projection areas of the three along the longitudinal direction are consistent (at this time, the side surfaces of each structural layer are aligned), it is beneficial to reduce the breakage or powdering of the structural layer caused by interlayer shear during high-pressure treatment.

[0280] The following is some description about the negative electrode layer.

[0281] The negative electrode layer can be provided by a negative electrode plate that can be used in solid-state batteries (the solid-state battery can be an all-solid-state battery) in the art, or the constituent materials of the negative electrode layer can be pressed into a film on one side surface of the solid electrolyte layer.

[0282] The negative electrode layer can be prepared by a dry process or a wet process. For example, a dry process can be used to form a film by pressing. Another example is a wet process can be used to form a film by coating.

[0283] The negative electrode layer includes a negative electrode active material layer, and the negative electrode active material layer includes a negative electrode active material.

[0284] Without limitation, the weight percentage of the negative electrode active material in the negative electrode active material layer may be ≥80 wt %, and further may be ≥90 wt %.

[0285] In some embodiments, the negative electrode active material is a lithium-indium alloy (InLi alloy).

[0286] In some embodiments, the negative electrode layer is an InLi alloy film.

[0287] In some embodiments, the negative electrode active material may also be a negative electrode active material known in the art that can be used for solid-state batteries (solid-state batteries can be all-solid-state batteries). As a non-limiting example, the negative electrode active material may include one or more of the following materials: elemental silicon, elemental tin, silicon-carbon negative electrode, silicon monoxide, graphite, and one or more of metallic lithium. However, the present application is not limited to these materials or substances, and other traditional materials that can be used as battery negative electrode active materials may also be used. These negative electrode active materials may be used alone or in combination of two or more.

[0288] In some embodiments, the negative electrode active material includes one or more of a carbon-based material, a silicon-based material, a tin-based material, and lithium titanate, as well as modified forms of any of the foregoing materials, wherein the modified form includes one or more of a doping modification and a coating modification. Both the doping modification method and the coating modification method can adopt or refer to existing modification methods in the art, including but not limited to the selection of element types and doping amounts. Carbon-based materials may include but are not limited to one or more of graphite materials, soft carbon, hard carbon, etc. Graphite materials may include one or more of artificial graphite and natural graphite.

[0289] In some embodiments, the negative electrode active material includes a carbon-based material and a silicon-based material. Without limitation, the combined weight of the carbon-based material and the silicon-based material may account for ≥80% of the total weight of the negative electrode active material, optionally ≥90%, further optionally ≥95%, further optionally ≥96%, and further optionally 100%. The combined weight of the graphite material and the silicon-based material may also account for any of the following percentages, or a percentage greater than or equal to any of the following percentages and less than or equal to 100%, or a range consisting of any two of the following percentages: 80%, 82%, 83%, 84%, 85%, 86%, 88%, 90%, 92%, 94%, 95%, 96%, 98%, and the like. The definition of carbon-based material can be found above. For example, the carbon-based material can be a graphite material. The content of the carbon-based material can also be found in any suitable embodiment described above.

[0290] In some embodiments, the negative electrode active material includes a carbon-based material and a silicon-based material in a mass ratio of 1:(1-3). The mass ratio of the carbon-based material to the silicon-based material may also be 1:(1-2), 1:(1.5-2), etc.

[0291] In some embodiments, the negative electrode layer may include a negative electrode current collector and a negative electrode active material layer disposed on at least one surface of the negative electrode current collector, wherein the negative electrode active material layer includes a negative electrode active material. As a non-limiting example, the negative electrode current collector has two surfaces that face away from each other in the thickness direction of the negative electrode current collector, and the negative electrode active material layer is disposed on either or both of the two facing surfaces of the negative electrode current collector. In some embodiments, the negative electrode current collector may be a metal foil or a composite current collector. For example, copper foil may be used as the metal foil. In the negative electrode current collector, the composite current collector may include a polymer material base layer and a metal layer formed on at least one surface of the polymer material base layer. In the negative electrode current collector, the composite current collector may be formed by forming a metal material on a polymer material base layer. Non-limiting examples of the metal material in the negative electrode current collector may include one or more of copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys. In the negative electrode current collector, non-limiting examples of the polymer material substrate may include one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), and the like.

[0292] In some embodiments, the negative electrode active material layer includes a binder (which may be referred to as a negative electrode binder). Non-limiting examples of negative electrode binders may include one or more of a rubber binder, polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), a vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, a vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, a tetrafluoroethylene-hexafluoropropylene copolymer, a fluorinated acrylate resin, polyacrylic acid (PAA), sodium polyacrylate (PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), polymethacrylic acid (PMAA), and carboxymethyl chitosan (CMCS). Without limitation, the weight percentage of the negative electrode binder in the negative electrode active material layer may be 0-10 wt%, further 0-5 wt%, further 1 wt%-5 wt%, and further optionally 1 wt%-3 wt%. The types of rubber binders may refer to the above, for example, may include one or more of styrene-butadiene rubber, nitrile rubber, hydrogenated nitrile rubber, and the like. In some embodiments, non-limiting examples of the negative electrode binder may include one or more of styrene-butadiene rubber (SBR), polyacrylic acid (PAA), sodium polyacrylate (PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), polymethacrylic acid (PMAA), and carboxymethyl chitosan (CMCS).

[0293] In some embodiments, the negative electrode active material layer includes a conductive agent (which may be referred to as a negative electrode conductive agent). Without limitation, the negative electrode conductive agent may include a carbon conductive agent. Without limitation, the negative electrode carbon conductive agent may include one or more of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers. In the negative electrode active material layer, the weight percentage of the negative electrode conductive agent may be 0 to 15 wt%, further optionally 0 to 10 wt%, further optionally 0 to 5 wt%, further optionally 0.1 wt% to 5 wt%. In the negative electrode active material layer, the weight percentage of the negative electrode conductive agent may also be 0.2 wt% to 5 wt%, 0.5 wt% to 5 wt%, 0.1 wt% to 3 wt%, and the like.

[0294] In some embodiments, the negative electrode active material layer may optionally include other additives, such as a thickener (e.g., sodium carboxymethyl cellulose (CMC-Na)). The weight percentage of the other additives in the negative electrode active material layer may be 0-15 wt %, further preferably 0-10 wt %, further preferably 0-5 wt %, further preferably 0-3 wt %, and further preferably 0-2 wt %.

[0295] In some embodiments, the negative electrode layer can be prepared by dispersing the components for preparing the negative electrode layer, such as the negative electrode active material, negative electrode conductive agent, negative electrode binder, and other optional components, in a solvent to form a negative electrode slurry. In some embodiments, the solvent is a non-aqueous solvent, and a non-limiting example of a non-aqueous solvent is N-methylpyrrolidone (NMP). Furthermore, the negative electrode slurry is coated on at least one surface of the negative electrode current collector. After drying and cold pressing, a negative electrode sheet can be obtained. The cold pressing can be performed using a cold rolling mill. The negative electrode current collector surface coated with the negative electrode slurry can be a single surface of the negative electrode current collector or both surfaces of the negative electrode current collector. The solid content of the negative electrode slurry can be 30 wt% to 70 wt%, and optionally 40 wt% to 60 wt%. The viscosity of the negative electrode slurry at room temperature can be adjusted to 2000 mPa·s to 10000 mPa·s, and optionally 3000 mPa·s to 10000 mPa·s. The compaction density of the negative electrode sheet can be 1.0g / cm 3 ~2.0g / cm 3 , 1.0g / cm 3 ~1.8g / cm 3 .

[0296] The following is some description about the solid electrolyte layer.

[0297] The solid electrolyte layer plays the role of conducting ions between the positive electrode layer and the negative electrode layer, and can also isolate the positive electrode layer and the negative electrode layer to prevent the positive and negative electrodes from short-circuiting.

[0298] The solid electrolyte layer includes a solid electrolyte. The solid electrolyte in the solid electrolyte layer can adopt a solid electrolyte known in the art that can be used for solid-state batteries (solid-state batteries can be all-solid-state batteries). As a non-limiting example, the solid electrolyte in the solid electrolyte layer may include one or more of the following materials: a sulfide solid electrolyte, a halide solid electrolyte, an oxide solid electrolyte, a polymer solid electrolyte, etc. The type of sulfide solid electrolyte in the solid electrolyte layer may be the same as or different from the sulfide solid electrolyte in the positive electrode layer.

[0299] In some embodiments, the solid electrolyte layer may be pressed from a solid electrolyte material into a solid electrolyte membrane.

[0300] In some embodiments, the thickness of the solid electrolyte layer may be 0.1 μm to 1000 μm, and optionally 10 μm to 100 μm.

[0301] In the present application, the positive electrode layer, the solid electrolyte layer and the negative electrode layer may be assembled in a stacked manner using at least one of a lamination manner and a winding manner.

[0302] Without limitation, the positive electrode sheet, solid electrolyte membrane and negative electrode sheet can be stacked in sequence (assembled in a stacking manner), the solid electrolyte can be placed between the positive electrode sheet and the negative electrode sheet, and a solid-state battery cell can be prepared by hot rolling (the solid-state battery cell can be an all-solid-state battery cell).

[0303] In some embodiments, a solid-state battery cell includes a solid-state battery cell.

[0304] In some embodiments, the solid-state battery cell is an all-solid-state battery cell.

[0305] In some embodiments, an all-solid-state battery cell includes an all-solid-state battery cell.

[0306] In some embodiments, referring to FIG7 , a solid-state battery cell (which may be an all-solid-state battery cell) includes a positive electrode layer 100, a solid electrolyte layer 200, and a negative electrode layer 300 stacked in sequence. For example, the positive electrode layer 100 in FIG7 is provided by the positive electrode sheet 10 shown in FIG2 .

[0307] In some embodiments, the negative electrode layer 300 includes a negative electrode current collector 310 and negative electrode active material layers 320 located on both sides of the negative electrode current collector 310 .

[0308] In some embodiments, based on the all-solid-state battery cell shown in FIG7 , the negative electrode layer 300 includes a negative electrode current collector 310 and negative electrode active material layers 320 located on both sides of the negative electrode current collector 310 , an example of which can be seen in FIG8 .

[0309] In some embodiments, a solid-state battery cell (the solid-state battery cell may be an all-solid-state battery cell) includes a plurality of stacked positive electrode layers 100 and negative electrode layers 300, with a solid electrolyte layer 200 disposed between any two adjacent positive electrode layers and negative electrode layers. An example of this is shown in FIG9 . The multiple positive electrode layers in the solid-state battery cell may be the same or different. The multiple negative electrode layers in the solid-state battery cell may be the same or different. The multiple solid electrolyte layers in the solid-state battery cell may be the same or different. The multiple positive electrode layers in the all-solid-state battery cell may be the same or different. The multiple negative electrode layers in the all-solid-state battery cell may be the same or different. The multiple solid electrolyte layers in the all-solid-state battery cell may be the same or different.

[0310] In some embodiments, the solid-state battery may include an outer packaging that can be used to encapsulate the solid-state battery cell.

[0311] In some embodiments, the all-solid-state battery may include an outer packaging that can be used to encapsulate the above-mentioned all-solid-state battery cell.

[0312] In some embodiments, the outer packaging of the solid-state battery (the solid-state battery may be an all-solid-state battery) may be a hard shell, such as a hard plastic shell, an aluminum shell, a steel shell, etc. The outer packaging of the solid-state battery (the solid-state battery may be an all-solid-state battery) may also be a soft package, such as a bag-type soft package. The material of the soft package may be plastic. Further, non-limiting examples of plastic may include one or more of polypropylene, polybutylene terephthalate, and polybutylene succinate.

[0313] A solid-state battery includes at least one solid-state battery cell. A solid-state battery may include one or more solid-state battery cells.

[0314] The all-solid-state battery includes at least one all-solid-state battery cell. The all-solid-state battery may include one or more all-solid-state battery cells.

[0315] The present application has no particular restrictions on the shape of the solid-state battery (the solid-state battery cell may be an all-solid-state battery cell), which may be cylindrical, square, or any other shape. For example, FIG10 shows an all-solid-state battery cell 5 having a square structure as an example.

[0316] In some embodiments of solid-state batteries, the outer packaging may include a housing and a cover plate. The housing may include a base plate and side plates connected to the base plate, with the base plate and side plates enclosing a receiving cavity. The housing has an opening communicating with the receiving cavity, and the cover plate can be positioned over the opening to seal the receiving cavity. The solid-state battery cell is encapsulated within the receiving cavity. The number of solid-state battery cells contained in a solid-state battery cell may be one or more, and those skilled in the art can select the appropriate number based on actual needs.

[0317] In some embodiments, referring to Figure 11, the outer packaging may include a shell 51 and a cover plate 53. The shell 51 may include a bottom plate and side plates connected to the bottom plate, and the bottom plate and the side plates enclose a receiving cavity. The shell 51 has an opening connected to the receiving cavity, and the cover plate 53 can be covered on the opening to close the receiving cavity. The all-solid-state battery cell 52 is encapsulated in the receiving cavity. The number of all-solid-state battery cells 52 contained in the all-solid-state battery cell 5 can be one or more, and those skilled in the art can select according to actual needs.

[0318] The solid-state battery can be a battery module 4 or a battery pack 1 .

[0319] The all-solid-state battery can be a battery module 4 or a battery pack 1 .

[0320] The battery module includes at least one solid-state battery cell.

[0321] In some embodiments, the battery module includes at least one all-solid-state battery cell. The number of all-solid-state battery cells contained in the battery module can be one or more, and those skilled in the art can select an appropriate number based on the application and capacity of the battery module.

[0322] In some embodiments, in a battery module, multiple solid-state battery cells may be arranged sequentially along the length of the battery module. Of course, they may also be arranged in any other manner. Furthermore, the multiple solid-state battery cells may be secured by fasteners. Optionally, the battery module may further include a housing having a storage space, wherein the multiple solid-state battery cells are housed in the storage space.

[0323] Figure 12 shows an example battery module 4. Referring to Figure 12 , within the battery module 4, multiple all-solid-state battery cells 5 may be arranged sequentially along the length of the battery module 4. Of course, they may also be arranged in any other manner. Furthermore, the multiple all-solid-state battery cells 5 may be secured together using fasteners.

[0324] Optionally, the battery module 4 may further include a housing having a receiving space, and the plurality of all-solid-state battery cells 5 are received in the receiving space.

[0325] In some embodiments, the battery modules may be assembled into a battery pack. The battery pack may contain one or more battery modules. Those skilled in the art may select an appropriate number based on the application and capacity of the battery pack.

[0326] Figures 13 and 14 illustrate an example battery pack 1. Referring to Figures 13 and 14 , the battery pack 1 may include a battery box and multiple battery modules 4 disposed within the battery box. The battery box comprises an upper case 2 and a lower case 3. The upper case 2 can be positioned over the lower case 3 to form an enclosed space for accommodating the battery modules 4. The multiple battery modules 4 can be arranged in any manner within the battery box.

[0327] In a third aspect of the present application, an electrical device is provided, which includes the solid-state battery described in the second aspect of the present application.

[0328] In some embodiments, an electrical device is provided, which includes the all-solid-state battery described in the second aspect of the present application.

[0329] In the fourth aspect of the present application, a method for preparing an all-solid-state battery is provided, comprising the following steps:

[0330] Providing a substrate including a solid electrolyte layer and a negative electrode layer stacked together, wherein the negative electrode layer is located on one side of the solid electrolyte layer;

[0331] The positive electrode sheet described in the first aspect of the present application is composited onto a side of the solid electrolyte layer away from the negative electrode layer to prepare a solid-state battery.

[0332] In some embodiments, a method for preparing an all-solid-state battery is provided, comprising the following steps:

[0333] Providing a substrate including a stacked solid electrolyte layer and a negative electrode layer, wherein the negative electrode layer is located on one side of the solid electrolyte layer;

[0334] The positive electrode sheet described in the first aspect of the present application is composited onto the side of the solid electrolyte layer away from the negative electrode layer to prepare an all-solid-state battery.

[0335] In some embodiments, the electrical device includes the all-solid-state battery of any embodiment provided in this application.

[0336] Without limitation, solid-state batteries (solid-state batteries may be all-solid-state batteries) may be used as power sources for electrical devices, or as energy storage units for electrical devices. Electrical devices may include, but are not limited to, mobile devices, electric vehicles, electric trains, ships and satellites, energy storage systems, and the like. Among them, mobile devices may be, for example, mobile phones, laptop computers, and the like; electric vehicles may be, for example, pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, electric motorcycles, electric tools, and the like, but are not limited thereto. The electrical device may also be used in fields such as military equipment, aerospace, and may also be used in energy storage power supply systems such as hydropower, thermal power, wind power, and solar power stations.

[0337] As an electrical device, a solid-state battery (the solid-state battery can be an all-solid-state battery) can be selected according to its usage requirements.

[0338] Figure 15 shows an example of an electric device 6. This device can be a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle. To meet the high power and high energy density requirements of solid-state batteries or all-solid-state batteries, a battery pack or battery module can be used.

[0339] As another example, the device may be a mobile phone, a tablet computer, a laptop computer, etc. Such a device is generally required to be lightweight and thin, and may use a solid-state battery (the solid-state battery may be an all-solid-state battery) as a power source.

[0340] Below, some embodiments of the present application are described. The embodiment described below is exemplary, is only used to explain the present application, and cannot be construed as limiting the present application. In the embodiment, if no technology or conditions are indicated, it is carried out according to the description above, or according to the technology or conditions described in the document in this area, or according to the product specification. Reagents used or instruments that do not indicate manufacturers are conventional products that can be obtained commercially, or can be synthesized in a conventional manner by commercially available products.

[0341] In the following examples, room temperature refers to 20°C to 30°C.

[0342] It should be noted that all-solid-state batteries are used as non-limiting examples of solid-state batteries in the following embodiments and examples.

[0343] Unless otherwise specified, the D v 50, obtained by referring to the particle size distribution laser diffraction method in accordance with GB / T 19077-2016, using a Mastersizer 2000E laser particle size analyzer from Malvern Instruments Ltd., UK.

[0344] The positive electrode active particles used in the following examples can be prepared by the above-mentioned method. For example, in Example 1, the positive electrode active material NCM811 (LiNi 0.8 Co 0.1 Mn 0.1 O2), the coating layer is Li3BO3, the positive electrode active body is NCM811, the weight proportion of the coating layer in the positive electrode active particles is 0.2wt%, and the thickness of the coating layer is about 5nm.

[0345] (1) Preparation of positive electrode active body: According to LiNi 0.8 Co 0.1 Mn 0.1O2 corresponding atomic molar ratio, lithium chloride, nickel oxide, cobalt oxide and manganese sulfate are mixed evenly, pure water is added, and the solid content of the slurry is adjusted to about 30wt%, and then it is placed in a beater for mixing for 30min to prepare a mixed liquid, and the mixed liquid is further placed in a ball mill, and ball milled with 0.1mm zirconium oxide grinding balls at a speed of 1000rpm for 12h, and the obtained slurry is placed in a spray dryer for drying and granulation to obtain a positive electrode material precursor; an air flow spray drying method is used for atomization, and the air inlet temperature of the equipment is set to 250℃, the air outlet temperature is 80℃, and the compressed air pressure is 0.7MPa; finally, the obtained positive electrode material precursor is placed in a tubular furnace and calcined at 950℃ for 13h in an oxygen atmosphere. After calcination, it is air flow crushed and sieved through 300 mesh to obtain a positive electrode active body composed of a powdered ternary NCM positive electrode material, which can be recorded as an NCM body.

[0346] (2) Preparation of coating material. Li2CO3 and B2O3 were mixed in a molar ratio of 3:1 and heated at 600℃ in air for 10h to obtain LBO powder. The LBO powder was ball milled at a speed of 400 rpm for 10 minutes, then paused for 20 minutes, and the "grinding / pause" operation was repeated 99 times. Then the LBO powder was pulverized to obtain D v 50 is reduced to less than or equal to 1 μm to obtain LBO coated material.

[0347] (3) Forming a coating layer on the surface of the positive electrode active body. The LBO coating material was mixed with the NCM body at a mass ratio of 3:7, ball-milled at 400 rpm for 30 min, and then calcined in air at 800°C for 2 h. The positive electrode active particles of Example 1 were prepared.

[0348] 1. Preparation Example

[0349] Example 1

[0350] (1) Prepare an adhesive solution containing an adhesive.

[0351] Paraxylene and nitrile rubber (NBR) were mixed to prepare glue, wherein the mass ratio of xylene to NBR was 95:5; the above solid and liquid raw materials were weighed and stirred at a speed of 1000 rpm at 25°C for 300 minutes to finally obtain a uniform adhesive glue solution.

[0352] In this example, NBR is used as both the first binder in the filling region and the second binder in the positive electrode active region.

[0353] (2) Prepare a positive electrode substrate including a positive electrode active area.

[0354] Li3BO3 coated positive electrode active material NCM811 (LiNi 0.8 Co0.1 Mn 0.1 O2) as the positive electrode active particles, the weight proportion of the Li3BO3 coating layer in the positive electrode active particles is 0.2wt%; Li6PS5Cl is used as the positive electrode solid electrolyte, vapor-grown carbon fiber (VGCF) is used as the positive electrode conductive agent, and the binder glue prepared in step (1) is used to provide a second binder. The positive electrode active particles, the positive electrode solid electrolyte, the positive electrode conductive agent and the second binder are mixed in a mass ratio of 78:19:1:2 to obtain a mixed slurry; by adding xylene to the above mixed slurry, the slurry solid content is controlled to 60wt%, and a positive electrode slurry is obtained. The carbon-coated aluminum foil was coated on both sides by gap coating. The size of the positive electrode active area was 5cm×8.5cm, the coating gap was 1cm, the blank space on the ear side was 5cm, and the total blank space width of the position of the filling area to be prepared was 1cm (the volume ratio of the formed filling area to the positive electrode active area was 20%, the thickness and length of the filling area were the same as those of the positive electrode active area, and the volume ratio and width ratio were numerically equal). After the coating was completed, the coating was dried at a drying temperature of 120°C. After drying, a positive electrode substrate including the positive electrode active area was obtained. The compacted density of the positive electrode active area was 3.5g / cm 3 .

[0355] (3) Prepare stabilizer slurry.

[0356] A binder NBR (first binder) is selected and mixed with a positive electrode stabilizer CaCl2, wherein the mass ratio of CaCl2 to NBR is 95:5; wherein NBR is added in the form of the binder glue prepared in step (1), and at the same time, the solid content of the filler slurry is controlled by adjusting the amount of solvent xylene added, and the solid content is adjusted to 50wt%. The above materials are stirred at a speed of 1000 rpm at 25°C for 300 minutes to mix uniformly, thereby obtaining a stabilizer slurry.

[0357] (4) Prepare a positive electrode sheet including a filling area and a positive electrode active area.

[0358] Adopt the gap coating method, use the stabilizer slurry prepared in step (3) to coat the positive electrode substrate including the positive electrode active area again, and coat the stabilizer slurry around the positive electrode active area, that is, coat the 5mm area outside the positive electrode active area, and the total area on both sides is 1cm.

[0359] Since the coating gap of the positive active area of ​​the positive electrode substrate is 1 cm during the preparation process, the stabilizer slurry can be applied to the gap of the positive active area, and the 5mm area outside the positive active area on the reserved ear side and the opposite side needs to be coated with the stabilizer slurry; after coating, it is dried at a temperature of 120°C. After drying, a positive electrode sheet including both the filling area and the positive active area is obtained; a customized knife die is used to die-cut the electrode sheet, and the lateral size of the active film layer corresponding to the knife die is 6cm×9.5cm.

[0360] (5) Prepare a solid electrolyte slurry for preparing a solid electrolyte layer.

[0361] An electrolyte slurry was prepared by mixing a binder NBR with a solid electrolyte Li6PS5Cl, wherein the mass ratio of Li6PS5Cl to NBR was 98:2, wherein NBR was added in the form of a binder glue prepared in step (1), and the solid content of the slurry was controlled by adjusting the amount of solvent xylene added, and the solid content was adjusted to 50 wt %. The slurry was stirred at a speed of 1000 rpm at 25°C for 300 min to mix evenly, and finally a solid electrolyte slurry was obtained.

[0362] (6) Prepare the negative electrode sheet.

[0363] Take nano-silicon, graphite, VGCF and binder polyvinylidene fluoride (PVDF), use the binder glue prepared in step (1) as the binder, and mix them in solvent N-methylpyrrolidone (NMP) at a mass ratio of 55:30:12:3. Use NMP to dissolve PVDF, stir and mix the binder glue with the materials of other components to form a slurry, and control the solid content of the slurry to 30wt% by adding NMP to the above mixed slurry. Mix the above materials to obtain a negative electrode slurry, and continuously coat the negative electrode slurry on both sides of the copper foil. The coating width of the electrode is 9.5cm. After coating, dry it at a drying temperature of 80℃. After drying, roll it and finally obtain a negative electrode. The compaction density of the negative electrode is 2.1g / cm 3 .

[0364] (7) Prepare a solid electrolyte-coated negative electrode sheet.

[0365] Solid electrolyte slurry is continuously coated on the negative electrode sheet, and then dried at 80°C. After drying, it is rolled to obtain a solid electrolyte-coated negative electrode sheet; a customized die is used to die-cut the electrolyte-coated negative electrode sheet, and the size of the negative electrode active material layer corresponding to the die is 6cm×9.5cm.

[0366] (8) Assemble to obtain an all-solid-state battery.

[0367] The die-cut pole pieces in steps (4) and (7) are aligned and packaged in a stacking manner. After packaging, they are subjected to warm isostatic pressing at 550 MPa and 90°C for 30 minutes. After the pressing is completed, the battery cells are welded and packaged to obtain an all-solid-state battery.

[0368] Example 2-6. Changing the coating layer composition of the positive electrode active particles.

[0369] An all-solid-state battery was prepared using a method substantially identical to that of Example 1, with the difference that the coating layer of the positive electrode active particles in the positive electrode active region was different. The same conditions as in Example 1 were used except that, in step (2), the coating layer materials coating the positive electrode active material were replaced with LiNbO3, Li2ZrO3, Li2SiO3, LiPO3, and Li2MnO4, respectively, while maintaining substantially the same coating layer thickness.

[0370] Example 7-11. Changing the type of solid electrolyte in the solid electrolyte layer.

[0371] The all-solid-state battery was prepared by the same method as in Example 1, except that the type of solid electrolyte used to prepare the solid electrolyte layer was different. In addition, the solid electrolyte materials used in the preparation of the solid electrolyte slurry in step (5) were replaced with Li3YCl6, Li 10 GeP2S 12 、Li7La3Zr2O 12 , Li2S-P2S5 and LiI-LiBr-Li2S-P2S5, and the other operating conditions are the same as those in Example 1.

[0372] Examples 12-21. Changing the positive electrode stabilizer.

[0373] An all-solid-state battery was prepared using a method substantially the same as in Example 1, except that the type of positive electrode stabilizer was different. The conditions were the same as in Example 1 except that the positive electrode stabilizers in the stabilizer slurry preparation process in step (3) were replaced with CaH2, anhydrous CuSO4, silica gel, lithium chloride, imidazole acid molecular sieve, porous carbon (activated carbon), Fe2O3, ZnO, Bi2O3, and CuO, respectively.

[0374] Examples 22-26. Variations in the positive electrode stabilizer, including dual absorbers.

[0375] An all-solid-state battery was prepared using a method substantially identical to that of Example 1, except that the positive electrode stabilizer was replaced with a combination of anhydrous CuSO4 and ZnO in mass ratios of 2:8, 4:6, 5:5, 6:4, and 8:2, respectively. The conditions were the same as in Example 1, except that the positive electrode stabilizer in step (3) of preparing the stabilizer slurry was replaced according to the aforementioned ratios.

[0376] Examples 27-28. Changing the positive electrode stabilizer to a dual physical absorber and a dual chemical absorber.

[0377] An all-solid-state battery was prepared using a method substantially identical to that of Example 1, with the difference being the type of positive electrode stabilizer. In Example 27, the positive electrode stabilizer was replaced with imidazolic acid molecular sieve and ZnO in a 1:1 mass ratio; in Example 28, the positive electrode stabilizer was replaced with activated carbon and CuO in a 1:1 mass ratio.

[0378] Example 29. Changing the positive electrode stabilizer.

[0379] An all-solid-state battery was prepared using a method substantially the same as in Example 1, with the difference being that the positive electrode stabilizer was replaced with anhydrous CuSO4 and Bi2O3 in a mass ratio of 1:1.

[0380] Example 30. Insulating material is added to the filling area.

[0381] An all-solid-state battery was prepared using a method substantially similar to that of Example 1, with the following differences: an insulating material, Al2O3, was added to the filling region; and when preparing the stabilizer slurry in step (3), a binder, NBR (a first binder), a positive electrode stabilizer, CaCl2, and an insulating material, Al2O3, were mixed, wherein the mass ratio of CaCl2, NBR, and insulating material, Al2O3, was 49:2:49. The remaining steps were the same as in Example 1.

[0382] Example 31. The positive electrode active particles are not provided with a coating layer.

[0383] An all-solid-state battery was prepared using a method substantially similar to that of Example 1, with the difference being that lithium iron phosphate (LFP) without a coating layer was used as the positive electrode active particles. The remaining steps were the same as in Example 1.

[0384] Example 32. Changing the content of the positive electrode stabilizer and the first binder in the filling area.

[0385] An all-solid-state battery was prepared using a method substantially the same as in Example 1, except that the contents of the positive electrode stabilizer and the first binder in the filling region were different, and the mass ratio of CaCl2 to NBR in step (3) was controlled to be 98:2. The remaining steps were the same as in Example 1.

[0386] Example 33.

[0387] An all-solid-state battery was prepared using a method substantially identical to that of Example 1, except that the warm isostatic pressing conditions during assembly of the all-solid-state battery in step (8) were different. The warm isostatic pressing conditions were adjusted as follows: pressure of 350 MPa, holding temperature of 60°C, and holding time of 10 min. Other conditions were the same as those of Example 1.

[0388] Examples 34-35. The positive electrode solid electrolyte further includes a halide solid electrolyte.

[0389] An all-solid-state battery was prepared using a method substantially the same as that in Example 1, except that the positive electrode solid electrolyte also included a halide solid electrolyte, and when preparing the solid electrolyte slurry in step (5), a portion of the sulfide solid electrolyte was replaced with a halide solid electrolyte Li3YCl6. The mass ratios of the sulfide solid electrolyte and the halide solid electrolyte in Examples 34 and 35 were 8:2 and 5:5, respectively.

[0390] Examples 36-37.

[0391] An all-solid-state battery was prepared using a method basically the same as that in Example 1, with the following differences: the weight proportion of the positive electrode stabilizer in the filling area, the weight proportion of the first binder in the filling area, the weight proportion of the insulating material in the filling area, the volume ratio of the filling area to the positive electrode active area (numerically equal to the width ratio of the filling area to the positive electrode active area), and the weight proportion of the coating layer in the positive electrode active particles. Please refer to Tables 1-3.

[0392] When adjusting the volume ratio of the filling area relative to the positive electrode active area, the width of the positive electrode active area remains unchanged (5 cm), and the relative volume ratio of the filling area is changed by changing the width of the filling area on both sides of the positive electrode active area. In addition, the width of the filling area on both sides of the positive electrode active area is made consistent.

[0393] Comparative Example 1: The overhang design was not adopted (no filling area was provided), and the sizes of the positive electrode active area and the negative electrode active material layer were the same.

[0394] This comparative example uses the same material formula as that of each layer in Example 1. Except for removing the coating process of the desiccant slurry during the preparation of the positive electrode sheet, the die-cutting size of the positive and negative electrode sheets remains consistent, and the corresponding lateral size of the die is 5cm×8.5cm. Other conditions are the same as in Example 1.

[0395] Comparative Example 2: No filling area is provided, and the size of the positive electrode active area is smaller than the size of the negative electrode active material layer.

[0396] This comparative example uses the same material formula as that of each layer in comparative example 1. In the preparation process of the positive electrode sheet, the step (4) of coating the stabilizer slurry is omitted. The positive electrode substrate including the positive electrode active area is used to assemble the all-solid-state battery. The die-cutting size of the positive and negative electrode sheets is 5 cm × 8.5 cm for the positive electrode, and 6 cm × 9.5 cm for the composite negative electrode and electrolyte layer. The preparation process of the battery is consistent with that of Example 1. At the same time, the desiccant slurry is coated on the outside of the battery. Other test methods and conditions are the same as those of Example 1.

[0397] Comparative Example 3: The positive electrode stabilizer is replaced with an insulating material.

[0398] An all-solid-state battery is prepared using a method substantially the same as that in Example 1, except that in step (3), all the positive electrode stabilizers in the filling area are replaced with insulating material TiO2.

[0399] Comparative Example 4: The positive electrode stabilizer was replaced with the first binder.

[0400] An all-solid-state battery was prepared by a method substantially the same as that in Example 1, except that: in step (3), all the positive electrode stabilizers in the filling area were replaced with NBR; in step (4), the binder glue prepared in step (1) was diluted to about 2000 mPa·s with xylene, and the diluted binder glue was used instead of the stabilizer slurry in Example 1 to be coated on the corresponding blank area outside the positive electrode active area, and then dried.

[0401] Comparative Example 5: The positive electrode stabilizer was replaced with a water-stable solid electrolyte.

[0402] The all-solid-state battery was prepared by the same method as in Example 1, except that in step (3), the positive electrode stabilizer in the filling area was completely replaced with a lithium-containing electrolyte LATP (Li 1.3 Al 0.3 Ti 1.7 (PO4)3).

[0403] Comparative Example 6-7. The positive electrode stabilizer was replaced with an insulating material.

[0404] All-solid-state batteries were prepared using methods substantially identical to those of Examples 34-35, with the difference that in step (3), the positive electrode stabilizer in the filling region was completely replaced with the insulating material Al2O3. Comparative Example 6 corresponds to Example 34, and Comparative Example 7 corresponds to Example 5.

[0405] The preparation parameters of Examples 1 to 37 and Comparative Examples 6-7 can also be found in Tables 1-3.

[0406] Table 1.

[0407] Table 2.

[0408] Table 3.

[0409] 2. All-solid-state battery related parameter test

[0410] The testing process of some battery performance parameters of the all-solid-state batteries prepared in each embodiment and each comparative example is as follows.

[0411] 1. Test of battery open circuit voltage and internal resistance

[0412] The battery open circuit voltage test process is as follows: at 25°C, the all-solid-state battery to be tested is tested for voltage and internal resistance using a multimeter.

[0413] 2. Determination of sulfide generation in all-solid-state batteries

[0414] For all-solid-state battery samples that have been warm isostatically pressed but not subjected to tab welding and packaging operations, the samples were placed in a sealed bag in a glove box that was fully dried with Ar gas (dew point below -60°C). 3 The polyacrylic acid box is placed in a constant temperature and humidity chamber maintained at room temperature (25°C) and 30% RH in an atmospheric atmosphere until the environment inside the polyacrylic acid box is the same as that inside the constant temperature and humidity chamber. Then, the sealed bag containing the sample is opened in the constant temperature and humidity chamber, and the sample is quickly placed in the polyacrylic acid box. The hydrogen sulfide concentration generated immediately after the sample is placed in the polyacrylic acid box and within 300 seconds is measured using a hydrogen sulfide sensor (GX-2009 manufactured by Riken Keiki). The volume V (in cubic centimeters) of hydrogen sulfide at standard atmospheric pressure at 25°C is calculated from the hydrogen sulfide concentration after 300 seconds, and divided by the mass m (in g) of all sulfide electrolyte materials in the solid-state battery. The amount of hydrogen sulfide generated is calculated to be V / m, in cm 3 ·g -1 , which represents the volume of hydrogen sulfide gas per gram of sulfide solid electrolyte parameters.

[0415] 3. Battery capacity retention test

[0416] The battery capacity retention rate test process is as follows: at 25°C, the all-solid-state battery to be tested is charged to 4.3V at a constant current of 1 / 3C, then charged to a current of 0.05C at a constant voltage of 4.3V, left for 5 minutes, and then discharged to 2V at a constant voltage of 1 / 3C. The obtained capacity is recorded as the initial capacity C0. Repeat the above steps for the same battery and record the discharge capacity Cn of the battery after the nth cycle. The battery capacity retention rate after each cycle is Pn = Cn / C0 × 100%; the data measured after 100 cycles under the above test conditions, that is, the value of P100, can be recorded as the "capacity retention rate after 100 cycles".

[0417] 3. Test Analysis Results

[0418] The test results can be found in Tables 4 and 5.

[0419] Examples 1 to 37 all have a filling area containing a positive electrode stabilizer set in the positive electrode plate under the overhang design, and all have lower internal resistance, lower hydrogen sulfide generation and better cycle performance.

[0420] Comparative Examples 1 to 7 do not include a filling area for the positive electrode stabilizer. Among them, Comparative Example 1 does not adopt an overhang design, the overhang design of Comparative Example 2 leaves a blank area without filling material, Comparative Examples 3, 6-7 replace the positive electrode stabilizer with an insulating material, Comparative Example 4 replaces the positive electrode stabilizer with a first binder, and Comparative Example 5 replaces the positive electrode stabilizer with a water-stable solid electrolyte. The results show that the internal resistance of Comparative Examples 1 to 7 is significantly increased, the amount of hydrogen sulfide generated is significantly increased, and the cycle performance is deteriorated to a certain extent.

[0421] Table 4.

[0422] Table 5.

[0423] The above description of the various embodiments tends to emphasize the differences between the various embodiments. The same or similar aspects can be referenced to each other and will not be repeated herein for the sake of brevity.

[0424] The technical features of the embodiments described above can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0425] It should be noted that the present application is not limited to the above-mentioned embodiments and examples. The above-mentioned embodiments and examples are only examples, and within the scope of the technical solution of the present application, embodiments that have substantially the same structure as the technical idea and exert the same effect are all included in the technical scope of the present application. The above-described embodiments and examples only express several embodiments of the present application, and the description thereof is relatively detailed, but it cannot be understood as a limitation on the scope of the patent. In addition, without departing from the scope of the subject matter of the present application, other methods of applying various modifications that can be thought of by those skilled in the art to the embodiments or examples, and combining some of the constituent elements in the embodiments or examples to construct the embodiments are also included in the scope of the present application.

Claims

1. A positive electrode sheet comprising a positive electrode current collector and an active membrane layer located on at least one side of the positive electrode current collector, wherein the thickness direction of the active membrane layer is designated as a longitudinal direction, and the direction perpendicular to the longitudinal direction is designated as a transverse direction; In the transverse direction, the active membrane layer includes a positive electrode active area and a filling area located at least partially around the positive electrode active area; in, The positive electrode active area includes positive electrode active particles and a positive electrode solid electrolyte, and the positive electrode solid electrolyte includes a sulfide solid electrolyte; the filling area includes a positive electrode stabilizer, and the positive electrode stabilizer includes at least one of a moisture absorber and a hydrogen sulfide absorber.

2. The positive electrode sheet according to claim 1, wherein: The positive electrode stabilizer meets one or more of the following characteristics: The weight proportion of the positive electrode stabilizer in the filling area is 30wt% to 99.5wt%; In the filling area, the mass ratio of the moisture absorbent to the hydrogen sulfide absorbent is 0 to 1; The weight proportion of the moisture absorbent in the filling area is 0wt% to 99.5wt%; The weight proportion of the hydrogen sulfide absorbent in the filling area is 0 wt % to 99.5 wt %.

3. The positive electrode sheet according to claim 1 or 2, wherein: The positive electrode stabilizer meets one or more of the following characteristics: The weight proportion of the positive electrode stabilizer in the filling area is 45wt% to 98wt%; In the filling area, the mass ratio of the moisture absorbent to the hydrogen sulfide absorbent is selected from 1:9 to 9:1; The weight proportion of the moisture absorbent in the filling area is 10wt% to 90wt%, and can be optionally 40wt% to 60wt%; The weight percentage of the hydrogen sulfide absorbent in the filling area is 10 wt% to 90 wt%, and can be optionally 40 wt% to 60 wt%.

4. The positive electrode sheet according to any one of claims 1 to 3, wherein: The positive electrode stabilizer meets one or more of the following characteristics: The positive electrode stabilizer includes the moisture absorber, and the moisture absorber includes one or more of a physical water absorbent and a chemical water absorbent; The positive electrode stabilizer includes the hydrogen sulfide absorber, and the hydrogen sulfide absorber includes one or more of a hydrogen sulfide physical absorber and a hydrogen sulfide chemical absorber.

5. The positive electrode sheet according to claim 4, wherein: The positive electrode stabilizer meets one or more of the following characteristics: The moisture absorbent includes a physical water absorbent, which includes one or more water absorbents selected from the group consisting of silica gel, molecular sieve, metal organic framework, and porous carbon; wherein the porous carbon water absorbent includes activated carbon; The moisture absorbent includes a chemical water absorbent, and the chemical water absorbent includes one or more of CaCl2, CaH2, anhydrous CuSO4, LiCl, FeCl3, FeO(OH), KMnO4, Na2CO3, Fe2O3, Fe(OH)3, ZnO, CuO, NiO and Al2O; The hydrogen sulfide absorbent includes a hydrogen sulfide physical absorbent, and the hydrogen sulfide physical absorbent includes one or more hydrogen sulfide absorbents selected from activated carbon, molecular sieves, and metal organic frameworks; The hydrogen sulfide absorbent includes a hydrogen sulfide chemical absorbent, and the hydrogen sulfide chemical absorbent includes one or more of Fe2O3, ZnO, Bi2O3, CuO and MnO.

6. The positive electrode sheet according to claim 4 or 5, wherein: The positive electrode stabilizer includes a dual absorber, which refers to a substance that serves as both the moisture absorber and the hydrogen sulfide absorber; The dual absorbent includes one or more of a dual physical absorbent and a dual chemical absorbent; The dual physical absorbent refers to a substance that absorbs water and hydrogen sulfide simultaneously based on a physical effect, and the dual chemical absorbent refers to a substance that absorbs water and hydrogen sulfide simultaneously based on a chemical effect.

7. The positive electrode sheet according to claim 6, wherein: The positive electrode stabilizer meets one or more of the following characteristics: The positive electrode stabilizer includes the dual physical absorbent, and the dual physical absorbent includes one or more of activated carbon, molecular sieve and metal organic framework; The positive electrode stabilizer includes the dual chemical absorber, and the dual chemical absorber includes one or more of ZnO and CuO.

8. The positive electrode sheet according to claim 6 or 7, wherein: The positive electrode stabilizer includes the dual chemical absorbent and the dual physical absorbent, and the dual physical absorbent includes one or more of activated carbon and molecular sieve.

9. The positive electrode sheet according to any one of claims 1 to 8, wherein: The filling area further includes a first adhesive; the first adhesive includes one or more of a rubber adhesive, carboxymethyl cellulose, a polyolefin adhesive, a polyurethane adhesive, a polyacrylate adhesive, a polyacrylic resin, polyvinylidene fluoride, polytetrafluoroethylene, a vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, a vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, and a tetrafluoroethylene-hexafluoropropylene copolymer; Wherein, the rubber adhesive comprises at least one of a fluorinated rubber adhesive and a rubber adhesive that does not contain fluorine element; The polyacrylate adhesive includes at least one of a fluorine-containing acrylic resin and a polyacrylate adhesive that does not contain fluorine.

10. The positive electrode sheet according to claim 9, wherein: The first adhesive includes one or more of styrene-butadiene rubber, nitrile rubber, hydrogenated nitrile rubber, polyacrylic resin and polyurethane adhesive.

11. The positive electrode sheet according to claim 9 or 10, wherein: The weight percentage of the first binder in the filling area is 0.5 wt % to 5 wt %.

12. The positive electrode sheet according to claim 9 or 10, wherein: The weight percentage of the first binder in the filling area is 2 wt % to 4 wt %.

13. The positive electrode sheet according to any one of claims 9 to 12, wherein: The filling area includes the first binder, and the positive electrode active area includes a second binder; the first binder and the second binder are of the same type.

14. The positive electrode sheet according to any one of claims 1 to 13, wherein: The filling region also includes insulating material.

15. The positive electrode sheet according to claim 14, wherein: The filling area satisfies one or more of the following characteristics: The insulating material includes one or more of an inorganic oxide insulating material, boehmite, non-woven fiber, and fibrous resin; optionally, the inorganic oxide insulating material includes one or more of Al2O3, MgO, SiO2, BaTiO3, BaCO3, Fe3O4, TiO2, Y2O3, Mn2O3, and Mn2O7; The weight percentage of the insulating material in the filling area is less than or equal to 69 wt %; In the filling region, a mass ratio of the insulating material to the positive electrode stabilizer is less than or equal to 2.

16. The positive electrode sheet according to claim 15, wherein: The filling area satisfies one or more of the following characteristics: The weight proportion of the insulating material in the filling area is 1wt% to 50wt%; In the filling region, a mass ratio of the insulating material to the positive electrode stabilizer is 0.5-1.

17. The positive electrode sheet according to any one of claims 1 to 16, wherein: The positive electrode active particles include a positive electrode active body and a coating layer located on at least a portion of the surface of the positive electrode active body. The positive electrode active body includes one or more of a lithium transition metal oxide and a lithium-containing phosphate, and the coating layer includes a lithium oxygen compound.

18. The positive electrode sheet according to claim 17, wherein: The lithium oxygen compound satisfies one or more of the following characteristics: The lithium oxygen compound includes one or more elements selected from the group consisting of B, Nb, Zr, Si, P, Mn, Zn, Al, Fe, and Na; The lithium oxygen compound accounts for 0.1 wt % to 5 wt % of the positive electrode active particles.

19. The positive electrode sheet according to claim 17 or 18, wherein: The lithium oxygen compound satisfies one or more of the following characteristics: The lithium oxygen compound includes one or more of Li3BO3, LiNbO3, Li2ZrO3, Li2SiO3, LiPO3 and Li2MnO4; The lithium oxygen compound accounts for 0.1 wt % to 2 wt % of the positive electrode active particles.

20. The positive electrode sheet according to any one of claims 1 to 19, wherein: The sulfide solid electrolyte includes at least one of a binary sulfide solid system and a ternary sulfide solid system; The binary sulfide solid state system includes one or more of Li2S-P2S5, Li2S-SiS2, Li2S-GeS2 and Li2S-B2S3; The ternary sulfide solid-state system includes one or more of an argyrodite-type sulfide electrolyte, a Li2S-MeS2-P2S5 ternary sulfide electrolyte, a lithium-germanium-phosphorus-sulfur sulfide electrolyte, a Li2S-P2S5-MS ternary sulfide electrolyte, a Li2S-P2S5-MCl ternary sulfide electrolyte and a thio-LISICON-type sulfide electrolyte; wherein Me includes one or more elements of Si, Ge, Sn and Al; and M includes one or more elements of Ge, Al, Sn, Pb, Sb, Si and As.

21. The positive electrode sheet according to any one of claims 1 to 20, wherein: The positive electrode stabilizer includes a moisture absorber, and the positive electrode solid electrolyte further includes a halide solid electrolyte; The halide solid electrolyte includes lithium, halogen and X element, wherein the X element includes one or more of Y, In, Zr, Sc, Ho, Mn, Cd and Pb, and the halogen includes one or more of Cl, Br and I.

22. The positive electrode sheet according to claim 21, wherein: The halide solid electrolyte includes Li3X 1 Cl6、LiX 1 I4、LiX 1 I3 and Li3X 1 One or more of Br6, X in the halide solid electrolyte 1 Includes one or more of Y, In, Sc, Ho, Mn, Cd and Pb.

23. The positive electrode sheet according to any one of claims 1 to 22, wherein: The positive electrode active area has a first side surface and a second side surface that are separated from each other, and the first side surface and the second side surface respectively intersect with the transverse direction; The filling areas are respectively arranged on outer sides of opposite areas of the first side surface and the second side surface.

24. The positive electrode sheet according to claim 23, wherein: The first side surface and the second side surface are completely covered by the filling area.

25. The positive electrode sheet according to any one of claims 1 to 24, wherein: In the lateral direction, the positive electrode active area is completely surrounded by the filling area.

26. The positive electrode sheet according to any one of claims 1 to 25, wherein: Measured by the projection area of the filling area in the transverse direction, the width of the filling area at different positions along the outer side of the positive electrode active area is greater than or equal to 0.2 mm.

27. The positive electrode sheet according to claim 25, wherein: Measured by the projection area of the filling area in the transverse direction, the width of the filling area at different positions along the outer side of the positive electrode active area is 0.2 mm to 10 mm, and can be optionally 0.5 mm to 10 mm.

28. The positive electrode sheet according to any one of claims 1 to 27, wherein: The volume ratio of the filling area to the positive electrode active area is greater than or equal to 0.2%.

29. The positive electrode sheet according to claim 28, wherein: The volume ratio of the filling area to the positive electrode active area is 0.2% to 20%, and can be optionally 0.5% to 10%.

30. The positive electrode sheet according to any one of claims 1 to 29, wherein: The thickness of the active membrane layer at different lateral positions is equal.

31. A solid-state battery comprising a positive electrode layer, a solid electrolyte layer and a negative electrode layer stacked in sequence, wherein: The positive electrode layer includes the positive electrode sheet according to any one of claims 1 to 30.

32. The solid-state battery according to claim 31, wherein The solid-state battery is an all-solid-state battery.

33. The solid-state battery according to claim 31 or 32, wherein: The projection areas of the positive electrode layer, the solid electrolyte layer, and the negative electrode layer along the longitudinal direction are consistent.

34. An electrical device comprising the solid-state battery according to any one of claims 31 to 33.

35. A method for preparing a solid-state battery, comprising the following steps: Providing a substrate including a solid electrolyte layer and a negative electrode layer stacked together, wherein the negative electrode layer is located on one side of the solid electrolyte layer; Composite the positive electrode sheet according to any one of claims 1 to 30 on a side of the solid electrolyte layer away from the negative electrode layer to prepare a solid-state battery; Optionally, the solid-state battery is an all-solid-state battery.

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