Solid-state battery and preparation method and application thereof

Abstract

The application discloses a solid-state battery and a preparation method and application thereof. The solid-state battery comprises: a positive electrode sheet, a positive electrode current collector and a positive electrode active material layer, the positive electrode active material layer comprising a positive electrode active material, a first conductive agent, a first oxide electrolyte and a first binder; a positive electrode oxide electrolyte layer, comprising a second oxide electrolyte and a second binder; a solid-state electrolyte layer; a negative electrode oxide electrolyte layer, comprising a third oxide electrolyte and a third binder; and a negative electrode sheet, a negative electrode current collector and a negative electrode active material layer, the negative electrode active material layer comprising a negative electrode active material, a second conductive agent, a fourth oxide electrolyte and a fourth binder. The application fundamentally solves the safety problem of the battery, improves the comprehensive electrical performance of the lithium ion battery under the premise of ensuring the structural stability of the active material, and improves the conductive performance between the active material layer and the solid-state electrolyte layer.

Description

Technical Field

[0001] This invention belongs to the field of batteries, specifically relating to a solid-state battery, its preparation method, and its application. Background Technology

[0002] Safety issues with power batteries are primarily influenced by three factors: oxygen, temperature, and organic solvents, which are ignition sources. The impact of organic solvents is paramount. Currently, mainstream power batteries use liquid electrolytes, which contain a large amount of organic solvents. Therefore, reducing or avoiding the use of organic solvents is an effective way to improve battery safety. Research on semi-solid-state or solid-state batteries is currently underway both domestically and internationally to fundamentally address power battery safety issues. Semi-solid-state or solid-state batteries exhibit good high-temperature resistance and relatively good performance at low temperatures. Solid-state batteries are now a hot research topic in the industry, and some companies have achieved mass production and application of semi-solid-state batteries. However, the conductivity between the positive / negative electrode active material layer and the solid electrolyte layer in solid-state batteries is poor, resulting in lower overall electrical performance.

[0003] Furthermore, the electrolytes used in solid-state batteries are mainly divided into three research systems: oxide, sulfide, and polymer electrolytes. Domestic companies primarily focus on oxide electrolytes, Japanese and Korean companies on sulfide electrolytes, and European and American companies on polymer electrolytes. Each electrolyte system has different advantages and disadvantages, thus affecting its application. Oxide electrolytes are easy to prepare and apply, but their high hardness affects the interfacial contact between the electrolyte and active materials. Sulfide electrolytes have conductivity comparable to liquid electrolytes, but they have poor chemical stability, are easily oxidized, and readily produce harmful gases such as hydrogen sulfide when exposed to water, making their production and processing complex. Polymer electrolytes have high conductivity at high temperatures and are easy to form into films, exhibiting good compatibility with both positive and negative electrodes. However, polymer electrolytes have drawbacks, including low conductivity at room temperature, low electrolyte oxidation potential, and the potential for lithium dendrites to penetrate the polymer film. In addition, some domestic companies are simultaneously developing semi-solid-state batteries, adding some liquid electrolyte to the solid-state electrolyte system. While this slightly improves battery safety performance, it does not fundamentally solve safety issues, and the high and low temperature performance of the batteries has not shown significant improvement. Summary of the Invention

[0004] This invention aims to at least partially solve one of the technical problems in related technologies. Therefore, the object of this invention is to propose a solid-state battery, its preparation method, and its applications. This invention fundamentally solves the battery safety problem, improves the overall electrical performance of lithium-ion batteries while ensuring the structural stability of the active material, and enhances the conductivity between the active material layer and the solid electrolyte layer.

[0005] To achieve the above objectives, in one aspect of the present invention, a solid-state battery is provided. According to an embodiment of the present invention, the solid-state battery comprises:

[0006] A positive electrode sheet, the positive electrode sheet comprising a positive current collector and a positive active material layer formed on the positive current collector, the positive active material layer comprising a positive active material, a first conductive agent, a first oxide electrolyte and a first binder;

[0007] A positive oxide electrolyte layer is disposed on the side of the positive active material layer away from the positive current collector, and the positive oxide electrolyte layer includes a second oxide electrolyte and a second binder;

[0008] A solid electrolyte layer is disposed on the side of the positive electrode oxide electrolyte layer away from the positive electrode sheet;

[0009] A negative oxide electrolyte layer is disposed on the side of the solid electrolyte layer away from the positive oxide electrolyte layer, and the negative oxide electrolyte layer includes a third oxide electrolyte and a third binder;

[0010] A negative electrode sheet, the negative electrode sheet comprising a negative electrode current collector and a negative electrode active material layer, the negative electrode active material layer being disposed on the side of the negative electrode oxide electrolyte layer away from the solid electrolyte layer, the negative electrode current collector being disposed on the side of the negative electrode active material layer away from the negative electrode oxide electrolyte layer, the negative electrode active material layer comprising a negative electrode active material, a second conductive agent, a fourth oxide electrolyte and a fourth binder.

[0011] According to embodiments of the solid-state battery of the present invention, firstly, since there is no free organic solvent inside the solid-state battery, the safety problem of the battery is fundamentally solved. Secondly, the conductive agent in the active material layer is composited between the active material and the oxide electrolyte, forming a complete conductive network structure around the active material particles, thereby improving the electrochemical performance and safety performance of the lithium-ion battery while ensuring the structural stability of the active material. Thirdly, the present invention provides an oxide electrolyte layer on both the positive and negative electrode sheets, replacing the separator to avoid short circuits between the positive and negative electrode materials, further improving the conductivity between the active material layer and the solid electrolyte layer.

[0012] In addition, the solid-state battery according to the above embodiments of the present invention may also have the following additional technical features:

[0013] In some embodiments of the present invention, the mass ratio of the positive electrode active material, the first conductive agent and the first oxide electrolyte is 100:(0.1-10):(3-20).

[0014] In some embodiments of the present invention, the thickness of the positive electrode active material layer is 150–450 μm.

[0015] In some embodiments of the present invention, the mass ratio of the second oxide electrolyte to the second binder is 100:(0.1-5).

[0016] In some embodiments of the present invention, the thickness of the positive oxide electrolyte layer is 10–80 μm.

[0017] In some embodiments of the present invention, the solid electrolyte layer comprises a fifth oxide solid electrolyte, a polymer electrolyte, a lithium salt, and an organic solvent, wherein the concentration of the lithium salt in the organic solvent is 2.5 to 4.5 mol / L, preferably 3 to 4 mol / L.

[0018] In some embodiments of the present invention, the mass ratio of the fifth oxide solid electrolyte, the polymer electrolyte, and the lithium salt is (0-1):(0.1-0.5):(0.8-1.2).

[0019] In some embodiments of the present invention, the fifth oxide electrolyte is selected from at least one of garnet-type solid electrolyte, perovskite-type solid electrolyte, LISICON-type solid electrolyte, and NASICON-type solid electrolyte.

[0020] In some embodiments of the present invention, the monomers of the polymer electrolyte include butyl acrylate and glycerol.

[0021] In some embodiments of the present invention, the lithium salt is selected from at least one of lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethylsulfonyl)imide, and lithium bis(oxalatoborate).

[0022] In some embodiments of the present invention, the organic solvent is selected from at least one of propylene carbonate, ethylene carbonate, butene carbonate, methyl ethyl carbonate, dimethyl carbonate, and diethyl carbonate.

[0023] In some embodiments of the present invention, the mass ratio of the negative electrode active material, the second conductive agent and the fourth oxide electrolyte is 100:(0.1-10):(3-20).

[0024] In some embodiments of the present invention, the thickness of the negative electrode active material layer is 200–500 μm.

[0025] In some embodiments of the present invention, the mass ratio of the third oxide electrolyte to the third binder is 100:(0.1-5).

[0026] In some embodiments of the present invention, the thickness of the negative electrode oxide electrolyte layer is 10–80 μm.

[0027] In some embodiments of the present invention, the positive electrode active material is selected from at least one of ternary NCM materials and LFP materials.

[0028] In some embodiments of the present invention, the first oxide electrolyte, the second oxide electrolyte, the third oxide electrolyte, and the fourth oxide electrolyte are each independently selected from at least one of garnet-type solid electrolyte, perovskite-type solid electrolyte, LISICON-type solid electrolyte, and NASICON-type solid electrolyte.

[0029] In some embodiments of the present invention, the first conductive agent and the second conductive agent are each independently selected from at least one of graphene and graphene oxide.

[0030] In some embodiments of the present invention, the negative electrode active material is selected from at least one of graphite material, hard carbon, soft carbon, silicon material and silicon-carbon composite material.

[0031] In a second aspect, the present invention provides a method for preparing a solid-state battery. According to an embodiment of the present invention, the method includes the following steps:

[0032] (1) A positive electrode active material layer is formed on the positive electrode current collector, the positive electrode active material layer comprising a positive electrode active material, a first conductive agent, a first oxide electrolyte and a first binder;

[0033] (2) A positive oxide electrolyte layer is formed on the side of the positive active material layer away from the positive current collector, the positive oxide electrolyte layer comprising a second oxide electrolyte and a second binder;

[0034] (3) A negative electrode active material layer is formed on the negative electrode current collector, wherein the negative electrode active material layer includes a negative electrode active material, a second conductive agent, a fourth oxide electrolyte and a fourth binder;

[0035] (4) A negative electrode oxide electrolyte layer is formed on the side of the negative electrode active material layer away from the negative electrode current collector, the negative electrode oxide electrolyte layer comprising a third oxide electrolyte and a third binder;

[0036] (5) A solid electrolyte layer is formed between the positive oxide electrolyte layer and the negative oxide electrolyte layer.

[0037] According to the method for preparing solid-state batteries according to embodiments of the present invention, the resulting solid-state batteries contain no free organic solvents, thus fundamentally solving the battery safety problem. Simultaneously, the conductive agent in the active material layer is composited between the active material and the oxide electrolyte, forming a complete conductive network structure around the active material particles, thereby improving the overall electrical performance of the lithium-ion battery while ensuring the structural stability of the active material. Furthermore, this method prepares an oxide electrolyte layer on both the positive and negative electrode sheets, replacing the separator to prevent short circuits between the positive and negative electrode materials, further improving the conductivity between the active material layer and the solid electrolyte layer.

[0038] In addition, the method for preparing solid-state batteries according to the above embodiments of the present invention may also have the following additional technical features:

[0039] In some embodiments of the present invention, step (1) includes:

[0040] (1-1) The positive electrode active material, the first conductive agent, the first oxide electrolyte and the first solvent are mixed, ball-milled and dried to obtain a composite positive electrode material;

[0041] (1-2) The composite positive electrode material, the first binder and the second solvent are mixed to form a positive electrode slurry, and the positive electrode slurry is coated on the positive electrode current collector to form a positive electrode sheet.

[0042] In some embodiments of the present invention, step (3) includes:

[0043] (3-1) Mix the negative electrode active material, the second conductive agent, the fourth oxide electrolyte and the third solvent, ball mill and dry to obtain the composite negative electrode material;

[0044] (3-2) The composite negative electrode material, the fourth binder and the fourth solvent are mixed to form a negative electrode slurry, and the negative electrode slurry is coated on the negative electrode current collector to form a negative electrode sheet.

[0045] In some embodiments of the present invention, step (5) includes:

[0046] (5-1) Mix the fifth oxide solid electrolyte, polymer electrolyte monomer, initiator, lithium salt and organic solvent to obtain a liquid electrolyte;

[0047] (5-2) The liquid electrolyte is injected into a solid lithium-ion battery to carry out a polymerization reaction in order to obtain a solid electrolyte layer.

[0048] In some embodiments of the present invention, the polymerization reaction is carried out at a temperature of 50–80°C and for a duration of 2–5 hours.

[0049] According to a third aspect of the present invention, a vehicle is provided, wherein, according to an embodiment of the present invention, the vehicle has the above-described solid-state battery or a solid-state battery prepared by the above-described method. Compared with the prior art, the vehicle of the present invention has higher safety and the battery has superior overall electrical performance. It should be noted that the features and effects described above for the solid-state battery and the method for preparing the solid-state battery also apply to this vehicle, and will not be repeated here.

[0050] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0051] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0052] Figure 1 This is a schematic diagram of the solid-state battery according to an embodiment of the present invention;

[0053] Among them, 100-positive current collector, 200-positive active material layer, 300-positive oxide electrolyte layer, 400-solid electrolyte layer, 500-negative oxide electrolyte layer, 600-negative active material layer, and 700-negative current collector. Detailed Implementation

[0054] The embodiments of the present invention are described in detail below. These embodiments are exemplary and are only used to explain the present invention, and should not be construed as limiting the invention. Where specific techniques or conditions are not specified in the embodiments, they are performed according to the techniques or conditions described in the literature in the art or according to the product instructions. Reagents or instruments used, unless otherwise specified, are all commercially available conventional products.

[0055] In one aspect of the invention, a solid-state battery is provided. According to an embodiment of the invention, refer to the accompanying drawing. Figure 1The solid-state battery includes a positive electrode sheet, which includes a positive current collector 100 and a positive active material layer 200 formed on the positive current collector 100. The positive active material layer 200 includes a positive active material, a first conductive agent, a first oxide electrolyte, and a first binder. A positive oxide electrolyte layer 300 is disposed on the side of the positive active material layer 200 away from the positive current collector 100, and includes a second oxide electrolyte and a second binder. A solid electrolyte layer 400 is disposed on the side of the positive oxide electrolyte layer 300 away from the positive electrode sheet. A negative oxide electrolyte layer 5... The negative electrode oxide electrolyte layer 500 is disposed on the side of the solid electrolyte layer 400 away from the positive electrode oxide electrolyte layer 300. The negative electrode oxide electrolyte layer 500 includes a third oxide electrolyte and a third binder. The negative electrode sheet includes a negative electrode current collector 700 and a negative electrode active material layer 600. The negative electrode active material layer 600 is disposed on the side of the negative electrode oxide electrolyte layer 500 away from the solid electrolyte layer 400, and the negative electrode current collector 700 is disposed on the side of the negative electrode active material layer 600 away from the negative electrode oxide electrolyte layer 500. The negative electrode active material layer 600 includes a negative electrode active material, a second conductive agent, a fourth oxide electrolyte, and a fourth binder. Therefore, since there is no free organic solvent inside the solid-state battery, the battery safety problem is fundamentally solved. Simultaneously, the first conductive agent in the positive electrode active material layer is composited between the positive electrode active material and the first oxide electrolyte, forming a complete conductive network structure around the positive electrode active material particles. This improves the overall electrical performance of the lithium-ion battery while ensuring the structural stability of the positive electrode active material. Similarly, the second conductive agent in the negative electrode active material layer is composited between the negative electrode active material and the fourth oxide electrolyte, forming a complete conductive network structure around the negative electrode active material particles. This also improves the overall electrical performance of the lithium-ion battery while ensuring the structural stability of the negative electrode active material. Furthermore, this invention provides an oxide electrolyte layer on both the positive and negative electrode sheets, replacing the separator to prevent short circuits between the positive and negative electrode materials, further improving the conductivity between the active material layer and the solid electrolyte layer.

[0056] According to some specific embodiments of the present invention, in the positive electrode active material layer, the mass ratio of the positive electrode active material, the first conductive agent, and the first oxide electrolyte is 100:(0.1-10):(3-20). This limits the mass ratio of the positive electrode active material, the first conductive agent, and the first oxide electrolyte to the aforementioned range, further ensuring the formation of a complete conductive network structure around the positive electrode active material particles, thereby further improving the overall electrical performance of the lithium-ion battery while ensuring the structural stability of the positive electrode active material. Furthermore, the thickness of the positive electrode active material layer is 150-450 μm.

[0057] According to further embodiments of the present invention, in the positive oxide electrolyte layer, the mass ratio of the second oxide electrolyte to the second binder is 100:(0.1-5), preferably 100:(0.5-3). By limiting the mass ratio of the second oxide electrolyte to the second binder within the above range, the second oxide electrolyte can be effectively bonded, while also increasing the contact between the second oxide particles, which is beneficial for ion transport. Furthermore, the thickness of the positive oxide electrolyte layer is 10-80 μm, preferably 20-50 μm. This limits the thickness of the positive oxide electrolyte layer within the above range, effectively avoiding contact between the positive and negative electrodes, and also reducing the ion transport distance.

[0058] According to further embodiments of the present invention, in the negative electrode active material layer, the mass ratio of the negative electrode active material, the second conductive agent, and the fourth oxide electrolyte is 100:(0.1-10):(3-20). This limits the mass ratio of the negative electrode active material, the second conductive agent, and the fourth oxide electrolyte to the aforementioned range, further ensuring the formation of a complete conductive network structure around the negative electrode active material particles, thereby further improving the overall electrical performance of the lithium-ion battery while ensuring the structural stability of the negative electrode active material. Furthermore, the thickness of the negative electrode active material layer is 200-500 μm.

[0059] According to further embodiments of the present invention, in the negative electrode oxide electrolyte layer, the mass ratio of the third oxide electrolyte to the third binder is 100:(0.1-5), preferably 100:(0.5-3). By limiting the mass ratio of the third oxide electrolyte to the third binder within the above range, the third oxide electrolyte can be effectively bonded, while also increasing the contact between the third oxide particles, which is beneficial for ion transport. Furthermore, the thickness of the negative electrode oxide electrolyte layer is 10-80 μm, preferably 20-50 μm. This limits the thickness of the negative electrode oxide electrolyte layer within the above range, effectively avoiding contact between the positive and negative electrodes, and also reducing the ion transport distance.

[0060] In the embodiments of the present invention, the specific type of the above-mentioned positive electrode active material is not particularly limited. As some specific examples, the positive electrode active material may be selected from at least one of ternary NCM materials and LFP materials. Similarly, the specific type of the above-mentioned negative electrode active material is also not particularly limited. As some specific examples, the negative electrode active material may be selected from at least one of graphite materials, hard carbon, soft carbon, silicon materials, and silicon-carbon composite materials.

[0061] In embodiments of the present invention, the specific types of the first and second conductive agents are not particularly limited. As specific examples, the first and second conductive agents can each be independently selected from at least one of graphene and graphene oxide. Similarly, the specific types of the first, second, third, and fourth oxide electrolytes are not particularly limited. As specific examples, the first, second, third, and fourth oxide electrolytes can each be independently selected from garnet-type Li7La3Zr2O. 12 At least one of (LLZO), perovskite, LISICON, and NASICON solid electrolytes. The first, second, third, and fourth binders described above are all conventional binders in the art, and their specific types are not particularly limited.

[0062] According to further embodiments of the present invention, the solid electrolyte layer comprises a fifth oxide solid electrolyte, a polymer electrolyte, a lithium salt, and an organic solvent. The concentration of the lithium salt in the organic solvent is 2.5–4.5 mol / L, preferably 3–4 mol / L. Thus, the flexible polymer electrolyte and the high-concentration lithium salt electrolyte with high conductivity improve the wettability between the fifth oxide electrolyte and the electrode material, reduce their contact resistance, and increase the conductivity of the composite electrolyte, thereby effectively improving the overall electrical performance of the solid-state battery. Furthermore, the fifth oxide electrolyte exhibits good high-temperature performance, and the high-concentration lithium salt electrolyte exhibits good low-temperature performance, thus effectively broadening the battery's operating temperature window. Specifically, the operating temperature range of conventional lithium-ion batteries is -30°C to 60°C; the solid-state battery of the present invention can support use within the range of -40°C to 70°C. It should be noted that the high-concentration electrolyte, due to its high ion carrier density, helps to increase the interfacial reaction frequency, thus essentially enabling high-speed electrode reactions, especially at low temperatures.

[0063] According to some specific embodiments of the present invention, the mass ratio of the fifth oxide solid electrolyte, the polymer electrolyte, and the lithium salt is (0-1):(0.1-0.5):(0.8-1.2). Thus, by limiting the mass ratio of the fifth oxide solid electrolyte, the polymer electrolyte, and the lithium salt to the above range, the wettability between the fifth oxide electrolyte and the electrode material is further effectively improved, the contact internal resistance between the two is reduced, and the conductivity of the composite electrolyte is increased, thereby further effectively improving the overall electrical performance of the solid-state battery.

[0064] The polymer electrolyte is formed by polymerizing monomers of a polymer electrolyte. As a specific example, the monomers of the polymer electrolyte include butyl acrylate and glycerol. The specific type of the aforementioned pentoxide electrolyte is not particularly limited. As some specific examples, the pentoxide electrolyte may be selected from at least one of garnet-type, perovskite-type, LISICON-type, and NASICON-type solid electrolytes. Similarly, the specific type of the aforementioned lithium salt is not particularly limited. As some specific examples, the lithium salt may be selected from at least one of lithium bis(fluorosulfonyl)imide (LiFSI), lithium bis(trifluoromethanesulfonyl)imide, and lithium bis(oxalatoborate). Likewise, the specific type of the aforementioned organic solvent is not particularly limited. As some specific examples, the organic solvent may be selected from at least one of propylene carbonate (PC), ethylene carbonate, butene carbonate, methyl ethyl carbonate, dimethyl carbonate, and diethyl carbonate.

[0065] In a second aspect, the present invention provides a method for preparing a solid-state battery. According to an embodiment of the present invention, the method includes the following steps:

[0066] S100: Forming a positive electrode active material layer on the positive electrode current collector.

[0067] In this step, a positive electrode active material layer is formed on the positive electrode current collector. The positive electrode active material layer includes a positive electrode active material, a first conductive agent, a first oxide electrolyte, and a first binder. Preferably, step S100 includes the following steps:

[0068] S110: Preparation of composite cathode materials

[0069] In this step, the positive electrode active material, the first conductive agent, the first oxide electrolyte, and the first solvent are mixed, ball-milled, and dried to obtain a composite positive electrode material. Specifically, the first conductive agent (e.g., graphene sheet) is first dispersed in the first solvent (e.g., N-methylpyrrolidone) and ultrasonically dispersed to obtain a first conductive agent dispersion. Then, the positive electrode active material and the first oxide electrolyte are added to the first conductive agent dispersion, and the mixture is effectively composited using mechanical ball milling. Finally, the ball-milled mixture is placed in a vacuum oven and vacuum-dried at high temperature (e.g., 120°C) for 24–48 hours to effectively evaporate the solvent. This allows the first conductive agent to be well composited between the positive electrode material and the oxide electrolyte, forming a complete conductive network structure around the positive electrode material particles. This improves the overall electrical performance of the lithium-ion battery while ensuring the structural stability of the positive electrode active material.

[0070] S120: Preparation of positive electrode sheet

[0071] In this step, the composite positive electrode material, the first binder, and the second solvent are mixed to form a positive electrode slurry. The positive electrode slurry is then coated onto the positive electrode current collector to form a positive electrode sheet containing positive electrode active material and oxide electrolyte material.

[0072] S200: A positive oxide electrolyte layer is formed on the side of the positive electrode active material layer away from the positive electrode current collector.

[0073] In this step, the second oxide electrolyte, the second binder, and the solvent (e.g., NMP) are mixed, dispersed evenly, and then uniformly coated onto the side of the positive electrode active material layer away from the positive electrode current collector to form the positive electrode oxide electrolyte layer.

[0074] S300: A layer of negative electrode active material is formed on the negative electrode current collector.

[0075] In this step, a negative electrode active material layer is formed on the negative electrode current collector. The negative electrode active material layer includes a negative electrode active material, a second conductive agent, a fourth oxide electrolyte, and a fourth binder. Step S300 includes the following steps:

[0076] S310: Preparation of composite anode materials

[0077] In this step, the negative electrode active material, the second conductive agent, the fourth oxide electrolyte, and the third solvent are mixed, ball-milled, and dried to obtain a composite negative electrode material. Specifically, the second conductive agent (e.g., graphene oxide) is first dispersed in the third solvent (e.g., deionized water) and ultrasonically dispersed to obtain a second conductive agent dispersion. Then, the negative electrode active material and the fourth oxide electrolyte are added to the second conductive agent dispersion, and the mixture is effectively composited using mechanical ball milling. Finally, the ball-milled mixture is placed in a vacuum oven and vacuum-dried at high temperature (e.g., 100°C) for 24–48 hours to effectively evaporate the solvent. This process allows the second conductive agent to be well composited between the negative electrode material and the oxide electrolyte, forming a complete conductive network structure around the negative electrode material particles. This improves the overall electrical performance of the lithium-ion battery while ensuring the structural stability of the negative electrode active material.

[0078] S320: Preparation of negative electrode sheet

[0079] In this step, the composite negative electrode material, the fourth binder, and the fourth solvent are mixed to form a negative electrode slurry. The negative electrode slurry is then coated onto the negative electrode current collector to form a negative electrode sheet containing a negative electrode active material and an oxide electrolyte material.

[0080] S400: A negative electrode oxide electrolyte layer is formed on the side of the negative electrode active material layer away from the negative electrode current collector.

[0081] In this step, the third oxide electrolyte, the third binder and the solvent are mixed, dispersed evenly and then uniformly coated on the side of the negative electrode active material layer away from the negative electrode current collector to form the negative electrode oxide electrolyte layer.

[0082] S500: A solid electrolyte layer is formed between the positive oxide electrolyte layer and the negative oxide electrolyte layer.

[0083] In this step, a solid electrolyte layer is formed between the positive electrode oxide electrolyte layer and the negative electrode oxide electrolyte layer. Preferably, step S500 includes:

[0084] S510: Mix the fifth oxide solid electrolyte, polymer electrolyte monomer, initiator (e.g., azobisisobutyronitrile ABVN), lithium salt and organic solvent to obtain a liquid electrolyte.

[0085] S520: Liquid electrolyte is injected into a solid-state lithium-ion battery, and the battery is heated in a vacuum environment to carry out a polymerization reaction in order to obtain a solid electrolyte layer, thereby producing a solid-state battery.

[0086] According to some specific embodiments of the present invention, the polymerization temperature is 50-80°C and the polymerization time is 2-5 hours, thereby ensuring that the polymerization reaction proceeds smoothly.

[0087] According to the method for preparing a solid-state battery according to embodiments of the present invention, firstly, the resulting solid-state battery contains no free organic solvents, thus fundamentally solving the battery safety problem. Secondly, the conductive agent in the active material layer is composited between the active material and the oxide electrolyte, forming a complete conductive network structure around the active material particles, thereby improving the overall electrical performance of the lithium-ion battery while ensuring the structural stability of the active material. Thirdly, this method prepares an oxide electrolyte layer on both the positive and negative electrode sheets, replacing the separator to avoid short circuits between the positive and negative electrode materials, further improving the conductivity between the active material layer and the solid electrolyte layer. Fourthly, the flexible polymer electrolyte and the high-concentration lithium salt electrolyte with high conductivity improve the wettability between the fifth oxide electrolyte and the electrode materials, reduce their contact resistance, and improve the conductivity of the composite electrolyte, thereby effectively improving the overall electrical performance of the solid-state battery; moreover, the fifth oxide electrolyte has good high-temperature performance, and the high-concentration lithium salt electrolyte has good low-temperature performance, thus effectively widening the battery's operating temperature window.

[0088] According to a third aspect of the present invention, a vehicle is provided, wherein, according to an embodiment of the present invention, the vehicle has the above-described solid-state battery or a solid-state battery prepared by the above-described method. Compared with the prior art, the vehicle of the present invention has higher safety, superior overall electrical performance of the battery, and effectively widens the battery's operating temperature window. It should be noted that the features and effects described above for the solid-state battery and the method for preparing the solid-state battery also apply to this vehicle, and will not be repeated here.

[0089] The embodiments of the present invention are described in detail below. It should be noted that the embodiments described below are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention. In addition, unless otherwise specified, all reagents used in the following embodiments are commercially available or can be synthesized according to the methods described herein or known to others. For reaction conditions not listed, they are also readily available to those skilled in the art.

[0090] Example 1

[0091] This embodiment provides a solid-state battery, the preparation method of which includes:

[0092] 1) Composite Cathode: First, graphene oxide is dispersed in N-methylpyrrolidone and ultrasonically dispersed to obtain a first conductive agent dispersion. Then, ternary NCM material and garnet-type solid electrolyte are added to the first conductive agent dispersion, and the mixture is effectively composited using mechanical ball milling. Finally, the ball-milled mixture is placed in a vacuum oven and dried at 120°C for 36 hours to effectively evaporate the solvent and allow graphene oxide to be well composited between the ternary NCM material and the garnet-type solid electrolyte, forming a composite cathode material. In this step, the mass ratio of ternary NCM material, graphene oxide, and garnet-type solid electrolyte is 100:5:12.

[0093] A composite cathode material, PVDF binder, and NMP are mixed to form a cathode slurry. This slurry is then coated onto the surface of an aluminum foil current collector to prepare a cathode sheet. In this step, the mass ratio of the composite cathode material to the binder is 100:2.5. The thickness of the cathode active material layer on the cathode sheet is 300 μm.

[0094] Garnet-type solid electrolyte, binder, and NMP are mixed, dispersed evenly, and then uniformly coated onto the side of the positive electrode active material layer away from the positive electrode current collector to form a positive electrode oxide electrolyte layer, thus obtaining a composite positive electrode. In this step, the mass ratio of garnet-type solid electrolyte to binder is 100:2. The thickness of the positive electrode oxide electrolyte layer is 45 μm.

[0095] 2) Composite Anode: First, graphene oxide is dispersed in deionized water and ultrasonically dispersed to obtain a second conductive agent dispersion. Then, graphite material and garnet-type solid electrolyte are added to the second conductive agent dispersion, and the mixture is effectively composited using mechanical ball milling. Finally, the ball-milled mixture is placed in a vacuum oven and dried at 100°C for 36 hours to effectively evaporate the solvent and allow graphene oxide to be well composited between the anode material and the garnet-type solid electrolyte, forming a composite anode material. In this step, the mass ratio of graphite material, graphene oxide, and garnet-type solid electrolyte is 100:5:12.

[0096] A composite negative electrode material, SBR binder, and deionized water are mixed to form a negative electrode slurry. This slurry is then coated onto the surface of a copper foil current collector to prepare a negative electrode sheet. In this step, the mass ratio of the composite negative electrode material to the binder is 100:2.5. The thickness of the negative electrode active material layer on the negative electrode sheet is 300 μm.

[0097] Garnet-type solid electrolyte, binder, and solvent are mixed and dispersed evenly, then uniformly coated onto the side of the negative electrode active material layer away from the negative electrode current collector to form a negative electrode oxide electrolyte layer, thus obtaining a composite negative electrode. In this step, the mass ratio of garnet-type solid electrolyte to binder is 100:2. The thickness of the negative electrode oxide electrolyte layer is 45 μm.

[0098] 3) Battery assembly: The composite positive electrode sheet and the composite negative electrode sheet are wound or stacked alternately to form a single core or stacked core, and then installed inside the casing.

[0099] 4) Injection of composite electrolyte: Garnet-type solid electrolyte, butyl acrylate, glycerol monomer, azobisisobutyronitrile initiator, and lithium difluorosulfonyl imide are dissolved in propylene carbonate and injected into the battery. The battery is heated under vacuum to achieve polymerization of the polymer monomers, ultimately forming a composite solid electrolyte inside the battery, thus obtaining a solid-state battery. In this step, the concentration of lithium difluorosulfonyl imide in propylene carbonate is 3 mol / L, and the mass ratio of garnet-type solid electrolyte, butyl acrylate, glycerol monomer, lithium difluorosulfonyl imide, and initiator is 0.5:0.2:0.4:1:0.02.

[0100] Example 2

[0101] This embodiment provides a solid-state battery, the preparation method of which includes:

[0102] 1) Composite Cathode: First, graphene oxide is dispersed in N-methylpyrrolidone and ultrasonically dispersed to obtain a first conductive agent dispersion. Then, ternary NCM material and garnet-type solid electrolyte are added to the first conductive agent dispersion, and the mixture is effectively composited using mechanical ball milling. Finally, the ball-milled mixture is placed in a vacuum oven and dried at 120°C for 36 hours to effectively evaporate the solvent and allow graphene oxide to be well composited between the ternary NCM material and the garnet-type solid electrolyte, forming a composite cathode material. In this step, the mass ratio of ternary NCM material, graphene oxide, and garnet-type solid electrolyte is 100:1:20.

[0103] A composite cathode material, binder, and NMP are mixed to form a cathode slurry. This slurry is then coated onto the surface of an aluminum foil current collector to prepare a cathode sheet. In this step, the mass ratio of the composite cathode material to the binder is 100:1.5. The thickness of the cathode active material layer on the cathode sheet is 150 μm.

[0104] Garnet-type solid electrolyte, binder, and NMP are mixed, dispersed evenly, and then uniformly coated onto the side of the positive electrode active material layer away from the positive electrode current collector to form a positive electrode oxide electrolyte layer, thus obtaining a composite positive electrode. In this step, the mass ratio of garnet-type solid electrolyte to binder is 100:1. The thickness of the positive electrode oxide electrolyte layer is 10 μm.

[0105] 2) Composite Anode: First, graphene oxide is dispersed in deionized water and ultrasonically dispersed to obtain a second conductive agent dispersion. Then, graphite material and garnet-type solid electrolyte are added to the second conductive agent dispersion, and the mixture is effectively composited using mechanical ball milling. Finally, the ball-milled mixture is placed in a vacuum oven and dried at 100°C for 36 hours to effectively evaporate the solvent and allow graphene oxide to be well composited between the anode material and the garnet-type solid electrolyte, forming a composite anode material. In this step, the mass ratio of graphite material, graphene oxide, and garnet-type solid electrolyte is 100:1:20.

[0106] A composite negative electrode material, SBR binder, and deionized water are mixed to form a negative electrode slurry. This slurry is then coated onto the surface of a copper foil current collector to prepare a negative electrode sheet. In this step, the mass ratio of the composite negative electrode material to the binder is 100:1.5. The thickness of the negative electrode active material layer on the negative electrode sheet is 300 μm.

[0107] Garnet-type solid electrolyte, binder, and solvent are mixed and dispersed evenly, then uniformly coated onto the side of the negative electrode active material layer away from the negative electrode current collector to form a negative electrode oxide electrolyte layer, thus obtaining a composite negative electrode. In this step, the mass ratio of garnet-type solid electrolyte to binder is 100:1. The thickness of the negative electrode oxide electrolyte layer is 10 μm.

[0108] 3) Battery assembly: The composite positive electrode sheet and the composite negative electrode sheet are wound or stacked alternately to form a single core or stacked core, and then installed inside the casing.

[0109] 4) Injection of composite electrolyte: Garnet-type solid electrolyte, butyl acrylate, glycerol monomer, azobisisobutyronitrile initiator, and lithium bis(fluorosulfonyl)imide are dissolved in propylene carbonate and injected into the battery. The battery is heated under vacuum to induce polymerization of the polymer monomers, ultimately forming a composite solid electrolyte inside the battery, thus producing a solid-state battery. In this step, the concentration of lithium bis(fluorosulfonyl)imide in propylene carbonate is 2.5 mol / L, and the mass ratio of garnet-type solid electrolyte, butyl acrylate, glycerol monomer, lithium bis(fluorosulfonyl)imide, and initiator is 0.3:0.2:0.4:1:0.02.

[0110] Example 3

[0111] This embodiment provides a solid-state battery, the preparation method of which includes:

[0112] 1) Composite Cathode: First, graphene oxide is dispersed in N-methylpyrrolidone and ultrasonically dispersed to obtain a first conductive agent dispersion. Then, ternary NCM material and garnet-type solid electrolyte are added to the first conductive agent dispersion, and the mixture is effectively composited using mechanical ball milling. Finally, the ball-milled mixture is placed in a vacuum oven and dried at 120°C for 36 hours to effectively evaporate the solvent and allow graphene oxide to be well composited between the ternary NCM material and the garnet-type solid electrolyte, forming a composite cathode material. In this step, the mass ratio of ternary NCM material, graphene oxide, and garnet-type solid electrolyte is 100:10:3.

[0113] A composite cathode material, SBR binder, and NMP are mixed to form a cathode slurry. This slurry is then coated onto the surface of an aluminum foil current collector to prepare a cathode sheet. In this step, the mass ratio of the composite cathode material to the binder is 100:2.5. The thickness of the cathode active material layer on the cathode sheet is 450 μm.

[0114] Garnet-type solid electrolyte, binder, and NMP are mixed, dispersed evenly, and then uniformly coated onto the side of the positive electrode active material layer away from the positive electrode current collector to form a positive electrode oxide electrolyte layer, thus obtaining a composite positive electrode. In this step, the mass ratio of garnet-type solid electrolyte to binder is 100:2. The thickness of the positive electrode oxide electrolyte layer is 80 μm.

[0115] 2) Composite Anode: First, graphene oxide is dispersed in deionized water and ultrasonically dispersed to obtain a second conductive agent dispersion. Then, graphite material and garnet-type solid electrolyte are added to the second conductive agent dispersion, and the mixture is effectively composited using mechanical ball milling. Finally, the ball-milled mixture is placed in a vacuum oven and dried at 100°C for 36 hours to effectively evaporate the solvent and allow graphene oxide to be well composited between the anode material and the garnet-type solid electrolyte, forming a composite anode material. In this step, the mass ratio of graphite material, graphene oxide, and garnet-type solid electrolyte is 100:10:3.

[0116] A composite negative electrode material, SBR binder, and deionized water are mixed to form a negative electrode slurry. This slurry is then coated onto the surface of a copper foil current collector to prepare a negative electrode sheet. In this step, the mass ratio of the composite negative electrode material to the binder is 100:2.5. The thickness of the negative electrode active material layer on the negative electrode sheet is 300 μm.

[0117] Garnet-type solid electrolyte, binder, and solvent are mixed and dispersed evenly, then uniformly coated onto the side of the negative electrode active material layer away from the negative electrode current collector to form a negative electrode oxide electrolyte layer, thus obtaining a composite negative electrode. In this step, the mass ratio of garnet-type solid electrolyte to binder is 100:2. The thickness of the negative electrode oxide electrolyte layer is 80 μm.

[0118] 3) Battery assembly: The composite positive electrode sheet and the composite negative electrode sheet are wound or stacked alternately to form a single core or stacked core, and then installed inside the casing.

[0119] 4) Injection of composite electrolyte: Garnet-type solid electrolyte, butyl acrylate, glycerol monomer, azobisisobutyronitrile initiator, and lithium bisfluorosulfonyl imide are dissolved in propylene carbonate and injected into the battery. The battery is heated under vacuum to induce polymerization of the polymer monomers, ultimately forming a composite solid electrolyte inside the battery, thus producing a solid-state battery. In this step, the concentration of lithium bisfluorosulfonyl imide in propylene carbonate is 4.5 mol / L, and the mass ratio of garnet-type solid electrolyte, butyl acrylate, glycerol monomer, lithium bisfluorosulfonyl imide, and initiator is 0.6:0.3:0.6:1:0.02.

[0120] Example 4

[0121] The only difference between this embodiment and Example 1 is that the concentration of lithium bis(fluorosulfonyl)imide in propylene carbonate is 1 mol / L; all other contents are the same as in Example 1.

[0122] Comparative Example 1

[0123] This comparative example provides a conventional liquid lithium-ion battery, the preparation method of which includes:

[0124] 1) Positive Electrode: A positive electrode slurry is formed by mixing the positive electrode material NCM, binder PVDF, and NMP. The positive electrode slurry is then coated onto the surface of the positive electrode current collector aluminum foil to prepare the positive electrode sheet. In this step, the mass ratio of the positive electrode material to the binder is 100:1.5. The thickness of the positive electrode active material layer on the positive electrode sheet is 150 μm.

[0125] 2) Negative Electrode: A negative electrode slurry is formed by mixing graphite (the negative electrode material), SBR (the binder), and deionized water. This slurry is then coated onto the surface of a copper foil current collector to prepare the negative electrode sheet. In this step, the mass ratio of the negative electrode material to the binder is 100:1.5. The thickness of the negative electrode active material layer on the negative electrode sheet is 300 μm.

[0126] 3) Battery assembly: The positive and negative electrode sheets are wound or stacked alternately to form a single core or stacked core, which is then installed inside the casing.

[0127] 4) Injection of liquid electrolyte: Traditional liquid electrolyte 1 mol / L lithium hexafluorophosphate + EC / EMC / DMC (mass ratio of 1:1:1) + film-forming additive VC (mass ratio of 0.5%) is used to prepare a traditional liquid lithium-ion battery.

[0128] Comparative Example 2

[0129] This embodiment provides a solid-state battery, the preparation method of which includes:

[0130] 1) Composite cathode: Ternary NCM material and garnet-type solid electrolyte are added to N-methylpyrrolidone and effectively composited using mechanical ball milling; finally, the ball-milled mixture is placed in a vacuum oven and dried at 120°C for 36 hours to effectively evaporate the solvent, forming the composite cathode material. In this step, the mass ratio of ternary NCM material to garnet-type solid electrolyte is 100:20.

[0131] A composite cathode material, binder, and NMP are mixed to form a cathode slurry. This slurry is then coated onto the surface of an aluminum foil current collector to prepare a cathode sheet. In this step, the mass ratio of the composite cathode material to the binder is 100:1.5. The thickness of the cathode active material layer on the cathode sheet is 150 μm.

[0132] Garnet-type solid electrolyte, binder, and NMP are mixed, dispersed evenly, and then uniformly coated onto the side of the positive electrode active material layer away from the positive electrode current collector to form a positive electrode oxide electrolyte layer, thus obtaining a composite positive electrode. In this step, the mass ratio of garnet-type solid electrolyte to binder is 100:1. The thickness of the positive electrode oxide electrolyte layer is 10 μm.

[0133] 2) Composite Anode: Graphite material and garnet-type solid electrolyte are added to deionized water, and the mixture is effectively composited using mechanical ball milling. Finally, the milled mixture is placed in a vacuum oven and dried at 100°C for 36 hours to effectively evaporate the solvent, forming the composite anode material. In this step, the mass ratio of graphite material to garnet-type solid electrolyte is 100:20.

[0134] A composite negative electrode material, SBR binder, and deionized water are mixed to form a negative electrode slurry. This slurry is then coated onto the surface of a copper foil current collector to prepare a negative electrode sheet. In this step, the mass ratio of the composite negative electrode material to the binder is 100:1.5. The thickness of the negative electrode active material layer on the negative electrode sheet is 300 μm.

[0135] Garnet-type solid electrolyte, binder, and solvent are mixed and dispersed evenly, then uniformly coated onto the side of the negative electrode active material layer away from the negative electrode current collector to form a negative electrode oxide electrolyte layer, thus obtaining a composite negative electrode. In this step, the mass ratio of garnet-type solid electrolyte to binder is 100:1. The thickness of the negative electrode oxide electrolyte layer is 10 μm.

[0136] 3) Battery assembly: Composite positive electrode sheets and composite negative electrode sheets are wound or stacked alternately to form a single core or stacked core, which is then installed inside the casing to produce a solid-state battery.

[0137] The batteries prepared in Examples 1-4 and Comparative Examples 1-2 were subjected to low-temperature discharge, high-temperature cycling, and safety performance tests, respectively. The test results are shown in Table 1. The results show that the batteries in Examples 1-4 and Comparative Example 2 are all solid-state batteries, and their safety performance is satisfactory. The traditional liquid lithium-ion battery in Comparative Example 1 failed the safety performance test. Furthermore, the high-temperature cycling efficiency of the batteries in Examples 1-4 and Comparative Example 2 is superior to that of Comparative Example 1. Comparative Example 1 exhibits good low-temperature discharge performance, while Comparative Example 2, using only an oxide solid electrolyte, suffers a significant decrease in low-temperature performance. Examples 1-3, using a composite solid electrolyte and a high-concentration electrolyte, significantly improve low-temperature performance, while Example 4, using a composite solid electrolyte and a low-concentration electrolyte, shows limited improvement in low-temperature performance. Therefore, Examples 1-3 not only passed the safety performance test but also demonstrate excellent low-temperature and high-temperature performance.

[0138] Table 1

[0139]

[0140] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0141] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A solid-state battery, characterized in that, include: A positive electrode sheet, the positive electrode sheet comprising a positive current collector and a positive active material layer formed on the positive current collector, the positive active material layer comprising a positive active material, a first conductive agent, a first oxide electrolyte and a first binder; A positive oxide electrolyte layer is disposed on the side of the positive active material layer away from the positive current collector, and the positive oxide electrolyte layer includes a second oxide electrolyte and a second binder; A solid electrolyte layer is disposed on the side of the positive electrode oxide electrolyte layer away from the positive electrode sheet; A negative oxide electrolyte layer is disposed on the side of the solid electrolyte layer away from the positive oxide electrolyte layer, and the negative oxide electrolyte layer includes a third oxide electrolyte and a third binder; A negative electrode sheet, the negative electrode sheet comprising a negative electrode current collector and a negative electrode active material layer, the negative electrode active material layer being disposed on the side of the negative electrode oxide electrolyte layer away from the solid electrolyte layer, the negative electrode current collector being disposed on the side of the negative electrode active material layer away from the negative electrode oxide electrolyte layer, the negative electrode active material layer comprising a negative electrode active material, a second conductive agent, a fourth oxide electrolyte and a fourth binder; The solid electrolyte layer comprises a fifth oxide solid electrolyte, a polymer electrolyte, a lithium salt, and an organic solvent, wherein the concentration of the lithium salt in the organic solvent is 2.5~4.5 mol / L; The mass ratio of the fifth oxide solid electrolyte, the polymer electrolyte, and the lithium salt is (0~1):(0.1~0.5):(0.8~1.2). The fifth oxide electrolyte is selected from at least one of garnet-type solid electrolyte, perovskite-type solid electrolyte, LISICON-type solid electrolyte and NASICON-type solid electrolyte; The monomers of the polymer electrolyte include butyl acrylate and glycerol; The lithium salt is selected from at least one of lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethylsulfonyl)imide, and lithium bis(oxalatoborate). The organic solvent is selected from at least one of propylene carbonate, ethylene carbonate, butene carbonate, ethyl methyl carbonate, dimethyl carbonate, and diethyl carbonate.

2. The solid-state battery according to claim 1, characterized in that, The mass ratio of the positive electrode active material, the first conductive agent, and the first oxide electrolyte is 100:(0.1~10):(3~20); The thickness of the positive electrode active material layer is 150~450μm.

3. The solid-state battery according to claim 1, characterized in that, The mass ratio of the second oxide electrolyte to the second binder is 100:(0.1~5); The thickness of the positive oxide electrolyte layer is 10~80μm.

4. The solid-state battery according to claim 1, characterized in that, The concentration of the lithium salt in the organic solvent is 3~4 mol / L.

5. The solid-state battery according to claim 1, characterized in that, The mass ratio of the negative electrode active material, the second conductive agent, and the fourth oxide electrolyte is 100:(0.1~10):(3~20); The thickness of the negative electrode active material layer is 200~500μm; The mass ratio of the third oxide electrolyte to the third binder is 100:(0.1~5); The thickness of the negative electrode oxide electrolyte layer is 10~80μm.

6. The solid-state battery according to claim 1, characterized in that, The positive electrode active material is selected from at least one of ternary NCM materials and LFP materials; The first oxide electrolyte, the second oxide electrolyte, the third oxide electrolyte, and the fourth oxide electrolyte are each independently selected from at least one of garnet-type solid electrolyte, perovskite-type solid electrolyte, LISICON-type solid electrolyte, and NASICON-type solid electrolyte; The first conductive agent and the second conductive agent are each independently selected from at least one of graphene and graphene oxide; The negative electrode active material is selected from at least one of graphite materials, hard carbon, soft carbon, silicon materials, and silicon-carbon composite materials.

7. A method for preparing a solid-state battery according to any one of claims 1-5, characterized in that, include: (1) A positive electrode active material layer is formed on the positive electrode current collector, the positive electrode active material layer comprising a positive electrode active material, a first conductive agent, a first oxide electrolyte and a first binder; (2) A positive oxide electrolyte layer is formed on the side of the positive active material layer away from the positive current collector, the positive oxide electrolyte layer comprising a second oxide electrolyte and a second binder; (3) A negative electrode active material layer is formed on the negative electrode current collector, wherein the negative electrode active material layer includes a negative electrode active material, a second conductive agent, a fourth oxide electrolyte and a fourth binder; (4) A negative electrode oxide electrolyte layer is formed on the side of the negative electrode active material layer away from the negative electrode current collector, the negative electrode oxide electrolyte layer comprising a third oxide electrolyte and a third binder; (5) A solid electrolyte layer is formed between the positive oxide electrolyte layer and the negative oxide electrolyte layer.

8. The method according to claim 7, characterized in that, Step (1) includes: (1-1) The positive electrode active material, the first conductive agent, the first oxide electrolyte and the first solvent are mixed, ball-milled and dried to obtain a composite positive electrode material; (1-2) The composite positive electrode material, the first binder and the second solvent are mixed to form a positive electrode slurry, and the positive electrode slurry is coated on the positive electrode current collector to form a positive electrode sheet.

9. The method according to claim 7, characterized in that, Step (3) includes: (3-1) Mix the negative electrode active material, the second conductive agent, the fourth oxide electrolyte and the third solvent, ball mill and dry to obtain a composite negative electrode material; (3-2) The composite negative electrode material, the fourth binder and the fourth solvent are mixed to form a negative electrode slurry, and the negative electrode slurry is coated on the negative electrode current collector to form a negative electrode sheet; Step (5) includes: (5-1) Mix the fifth oxide solid electrolyte, polymer electrolyte monomer, initiator, lithium salt and organic solvent to obtain a liquid electrolyte; (5-2) The liquid electrolyte is injected into a solid lithium-ion battery to carry out a polymerization reaction in order to obtain a solid electrolyte layer; The polymerization reaction is carried out at a temperature of 50-80°C for 2-5 hours.

10. A vehicle, characterized in that, The solid-state battery includes any one of claims 1 to 6 or a solid-state battery prepared by any one of claims 7 to 9.

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