Solid-state battery and method of manufacturing the same

Abstract

The application provides a solid-state battery and a preparation method thereof. The solid-state battery comprises: a positive electrode, the positive electrode comprising a positive electrode material; a negative electrode, the negative electrode comprising a negative electrode current collector and a negative electrode material located on at least one side of the negative electrode current collector; and a first solid-state electrolyte located between the positive electrode and the negative electrode; wherein the positive electrode material comprises a polythioquinone polymer and a second solid-state electrolyte. The positive electrode material provided by the application reduces the reactivity between the positive electrode material and the first solid-state electrolyte of the solid-state battery under the joint action of the energy level difference and the pi-pi conjugation, and improves the cycle stability of the battery.

Description

Technical Field

[0001] This application relates to the field of batteries, and more particularly to a solid-state battery and a method for preparing the same. Background Technology

[0002] All-solid-state batteries have become the most promising next-generation rechargeable battery system due to their advantages such as high safety, good stability, and high energy density. Based on the chemical system of the cathode material, all-solid-state batteries can be divided into organic and inorganic types. Compared to inorganic all-solid-state batteries, organic all-solid-state batteries generally have a lower proportion of active material in the cathode. This is mainly because organic electrode materials have lower tap density, electronic conductivity, and ionic conductivity, requiring a higher proportion of solid electrolyte and conductive carbon in the corresponding composite electrode to maintain efficient electron and ion conduction and ensure the effective electrochemical reaction. However, this also causes significant volume expansion during cycling, thus affecting the cycle stability of the all-solid-state battery. Summary of the Invention

[0003] Purpose of the invention: This application provides a solid-state battery that improves the cycle stability of the battery.

[0004] The first aspect of this application provides a solid-state battery, comprising:

[0005] Positive electrode, wherein the positive electrode comprises a positive electrode material;

[0006] The negative electrode includes a negative electrode current collector and a negative electrode material located on at least one side of the negative electrode current collector;

[0007] and a first solid electrolyte located between the positive electrode and the negative electrode;

[0008] The positive electrode material includes a polythioquinone polymer and a second solid electrolyte.

[0009] In some embodiments, the mass ratio of the polythioquinone polymer to the second solid electrolyte is 20–70:30–80.

[0010] In some embodiments, the chemical formula of the first solid electrolyte is: Li X PS Y Cl z R 1 w Where 2≤x≤12, 0.5≤y≤8, 0.1≤z≤3, 0≤w≤5, R 1 It is selected from any one of the following groups: fluorine atom, chlorine atom, bromine atom, iodine atom, nitro group, cyano group, sulfonic acid group, acyl group, and carboxyl group.

[0011] In some embodiments, the second solid-state electrolyte has a chemical formula: Li a PS b Cl c R 2 d wherein 2≤a≤12, 0.5≤b≤8, 0.1≤c≤3, 0.1≤d≤5, R 2 is selected from any one of a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a nitro group, a cyano group, a sulfonic acid group, an acyl group, and a carboxyl group.

[0012] In some embodiments, the negative electrode material comprises a composite binder and silicon powder, and the mass ratio of the composite binder and the silicon powder is 0.5-20:80-99.5.

[0013] The second aspect of the present application provides a preparation method of a solid-state battery, comprising:

[0014] preparing a positive electrode, the positive electrode comprising a positive electrode material;

[0015] preparing a negative electrode, the negative electrode comprising a negative electrode current collector and a negative electrode material located on at least one side of the negative electrode current collector;

[0016] sequentially assembling the positive electrode, the first solid-state electrolyte, and the negative electrode to obtain a solid-state battery.

[0017] wherein the positive electrode material comprises a poly-sulfonequinone polymer and a second solid-state electrolyte.

[0018] In some embodiments, the preparation method of the poly-sulfonequinone polymer comprises:

[0019] dissolving a quinone compound and a sulfide in a first solvent, uniformly mixing, and then heating to react under an inert atmosphere to obtain a poly-sulfonequinone polymer.

[0020] In some embodiments, the molar mass ratio of the quinone compound and the sulfide is 1:1-10.

[0021] In some embodiments, the concentration of the quinone compound in the first solvent is 0.001 mol / L-1 mol / L.

[0022] In some embodiments, the concentration of the sulfide in the first solvent is 0.001 mol / L-1 mol / L.

[0023] In some embodiments, the heating temperature is 85-300°C, and the heating time is 1-24 h.

[0024] In some embodiments, the quinone compound is selected from at least one of benzoquinone derivatives, anthraquinone derivatives, naphthoquinone derivatives, phenanthrenequinone derivatives having an electron-donating group selected from any one of dialkylamino, alkylamino, amino, hydroxyl, alkoxy.

[0025] In some embodiments, the sulfide is selected from at least one of sodium sulfide, sodium polysulfide, lithium sulfide, lithium polysulfide, selenium sulfide, cadmium sulfide, aluminum sulfide, silver sulfide.

[0026] In some embodiments, the first solvent is selected from at least one of N,N-diisopropylethylamine, N,N-dipropylethylamine, N,N-diisopropylethylendiamine, N-isopropylethylendiamine, N-methylpyrrolidone, pyrrolidone, methylpyrrolidone, 3-pyrrolidone.

[0027] In some embodiments, the inert atmosphere is selected from argon or nitrogen.

[0028] In some embodiments, the negative electrode material comprises a composite binder and silicon powder, and a preparation method of the composite binder comprises:

[0029] dissolving the first polymer monomer in the second polymer monomer, stirring, mixing, and reacting to obtain the composite binder;

[0030] The mass ratio of the first polymer monomer to the second polymer monomer is 0.01-20:80-99.9.

[0031] In some embodiments, the first polymer monomer is selected from at least one of lithium acrylate, acrylic acid, lithium methacrylate.

[0032] In some embodiments, the second polymer monomer is selected from at least one of polyethylene glycol methacrylate, polyethylene glycol diacrylate, polyethylene glycol diacrylate, polyethylene glycol allyl methyl ether, polyethylene glycol methyl ether acrylate, polyethylene glycol monomaleate.

[0033] The positive electrode material provided in the present application reduces the reactivity between the positive electrode material and the first solid-state electrolyte in the solid-state battery under the joint action of the energy level difference and the π-π conjugation, and improves the cycle stability of the battery. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present application will be clearly and completely described below in combination with the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0035] In the present specification, a numerical range indicated using "~" shows a range including a range in which the values recited before and after the "~" are respectively taken as the minimum value and the maximum value.

[0036] The first aspect of the present application provides a solid-state battery, comprising: a positive electrode, a negative electrode, and a first solid-state electrolyte between the positive electrode and the negative electrode, the positive electrode comprising a positive electrode material; the negative electrode comprising a negative electrode current collector and a negative electrode material on at least one side of the negative electrode current collector; wherein the positive electrode material comprises a poly-sulfoquinone polymer and a second solid-state electrolyte.

[0037] It can be understood that the positive electrode material provided by the present application, comprising a poly-sulfoquinone polymer and a second solid-state electrolyte, reduces the reactivity between the first solid-state electrolyte under the joint action of the energy level difference and the π-π conjugation, improves the material utilization rate of the solid-state battery, and improves the cycle stability of the battery.

[0038] In some embodiments, the mass ratio of the poly-sulfoquinone polymer and the second solid-state electrolyte is 20-70:30-80. Specifically, the mass ratio of the poly-sulfoquinone polymer and the second solid-state electrolyte can be any one of 20:80, 30:70, 40:60, 50:50, 60:40, 70:30 or a range composed of any two of them.

[0039] It can be understood that the poly-sulfoquinone polymer has a long π-π conjugated structure, which can improve the π-π interaction between molecules, reduce the spontaneous reaction of the poly-sulfoquinone polymer with the first solid-state electrolyte, speed up the charge transfer rate, and improve the reaction kinetics of the positive electrode material.

[0040] In some embodiments, the first solid-state electrolyte has a chemical formula: Li X PS Y Cl z R 1 w wherein 2≤x≤12, 0.5≤y≤8, 0.1≤z≤3, 0≤w≤5, R 1The atom is selected from any one of the following: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), nitro (-NO2), cyano (-CN), sulfonic acid (-SO3H), acyl (-COR), and carboxyl (-COOH). Specifically, x can be any one or any two values ​​from 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12; y can be any one or any two values ​​from 0.5, 1, 2, 3, 4, 5, 6, 7, 8; z can be any one or any two values ​​from 0.1, 0.5, 1, 1.5, 2, 2.5, 3; and w can be any one or any two values ​​from 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5.

[0041] It is understandable that the first solid electrolyte contains lithium atoms (Li), phosphorus atoms (P), sulfur atoms (S), chlorine atoms (Cl), and a first dopant atom R. 1 R 1 Selected from any one of F, Cl, Br, I, -NO2, -CN, -SO3H, -COR, -COOH; the first doped atom R 1 As an electron-withdrawing group, it can reduce the HOMO (Highest Occupied Molecular Orbital) value of the first solid electrolyte, making it easier for the first solid electrolyte to gain electrons and be reduced.

[0042] In some embodiments, the general chemical formula of the second solid electrolyte is: Li a PS b Cl c R 2 d Where 2≤a≤12, 0.5≤b≤8, 0.1≤c≤3, 0.1≤d≤5, R 2The atom is selected from any one of the following: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), nitro (-NO2), cyano (-CN), sulfonic acid (-SO3H), acyl (-COR), and carboxyl (-COOH). Specifically, the value of a can be any one or any two of the following: 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12; specifically, the value of b can be any one or any two of the following: 0.5, 1, 2, 3, 4, 5, 6, 7, 8; specifically, the value of c can be any one or any two of the following: 0.1, 0.5, 1, 1.5, 2, 2.5, 3; specifically, the value of d can be any one or any two of the following: 0.1, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5.

[0043] It is understandable that the second solid electrolyte contains lithium atoms (Li), phosphorus atoms (P), sulfur atoms (S), chlorine atoms (Cl), and a second dopant atom R. 2 R 2 Selected from any one of F, Cl, Br, I, -NO2, -CN, -SO3H, -COR, -COOH; the second doped atom R 2 As an electron-withdrawing group, it can lower the HOMO value of the second solid electrolyte, making it easier for the second solid electrolyte to gain electrons and be reduced.

[0044] In some embodiments, the negative electrode material includes a composite binder and silicon powder, wherein the mass ratio of the composite binder to silicon powder is 0.5–20:80–99.5. Specifically, the mass ratio of the composite binder to silicon powder can be any one or any two of the following ratios: 0.5:99.5, 1:99, 5:95, 10:90, 15:85, and 20:80.

[0045] Understandably, the composite binder provides excellent mechanical strength and elasticity to the negative electrode material, effectively suppressing the volume expansion of silicon and reducing crack formation. The ether bonds form conductive channels for ions, improving the ionic conductivity of the electrode, establishing a high-speed ion-electron conduction path, achieving high electronic conductivity, and improving the cycle stability of the battery. By controlling the mass ratio of composite binder to silicon powder to 0.5–20:80–99.5, the adhesion between the negative electrode material and the negative electrode current collector can be guaranteed. At the same time, the composite binder provides excellent mechanical strength and elasticity to the negative electrode material, effectively suppressing the volume expansion of silicon and reducing crack formation.

[0046] A second aspect of this application provides a method for preparing a solid-state battery, comprising:

[0047] Step S1: preparing a positive electrode, the positive electrode comprising a positive material; wherein the positive material comprises a poly-sulfone-based polymer and a second solid-state electrolyte;

[0048] Step S2: preparing a negative electrode, the negative electrode comprising a negative current collector and a negative material located on at least one side of the negative current collector;

[0049] Step S3: sequentially assembling the positive electrode, the first solid-state electrolyte, and the negative electrode to obtain a solid-state battery.

[0050] It can be understood that the positive material provided by the present application reduces the reactivity between the positive material and the first solid-state electrolyte of the solid-state battery under the joint action of the energy level difference and the pi-pi conjugation, improves the material utilization rate of the solid-state battery, and improves the cycle stability of the battery.

[0051] In some embodiments, the mass ratio of the poly-sulfone-based polymer and the second solid-state electrolyte is 20-70:30-80. Specifically, the mass ratio of the poly-sulfone-based polymer and the second solid-state electrolyte can be any one of 20:80, 30:70, 40:60, 50:50, 60:40, 70:30 or a range composed of any two of them.

[0052] It can be understood that the poly-sulfone-based polymer has a long pi-pi conjugation structure, which can improve the intermolecular pi-pi interaction, reduce the spontaneous reaction between the poly-sulfone-based polymer and the first solid-state electrolyte, speed up the charge transfer rate, and improve the reaction kinetics of the positive material.

[0053] In some embodiments, the preparation method of the poly-sulfone-based polymer comprises:

[0054] The quinone compound and the sulfide are dissolved in a first solvent, uniformly mixed, and then heated to react under an inert atmosphere to obtain the poly-sulfone-based polymer.

[0055] It can be understood that the quinone compound extends the pi-pi conjugation structure through polymerization, which is conducive to improving the intermolecular pi-pi interaction, thereby reducing the spontaneous reaction between the positive material and the first solid-state electrolyte, speeding up the charge transfer rate, and improving the reaction kinetics of the positive material.

[0056] In some embodiments, after heating to react under an inert atmosphere, the method further comprises:

[0057] The second solvent is used for washing, and then drying treatment is performed to obtain the poly-sulfone-based polymer.

[0058] In some embodiments, the second solvent is selected from any one of methanol, distilled water, acetone, and propanol.

[0059] In some embodiments, the drying temperature is 60-150°C and the drying time is 6-48h during the drying process. Specifically, the drying temperature can be any one of 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C or a range between any two of them; the drying time can be any one of 6h, 10h, 15h, 20h, 25h, 30h, 35h, 40h, 45h, 48h or a range between any two of them.

[0060] In some embodiments, the mass ratio of the quinone compound and the sulfide is 1:1-10. Specifically, the mass ratio of the quinone compound and the sulfide can be any one of 1:1, 1:2, 1:3, 1:4, 1:5, 1:6, 1:7, 1:8, 1:9, 1:10 or a range between any two of them.

[0061] It can be understood that the quinone compound is a compound containing a quinone group, and by mixing and polymerizing the quinone compound and the sulfide, the quinone group in the quinone compound can react with the sulfur atom in the sulfide to form a new chemical bond, thereby forming a polysulfone quinone polymer.

[0062] In some embodiments, the concentration of the quinone compound in the first solvent is 0.001-1 mol / L. Specifically, the concentration of the quinone compound in the first solvent can be any one of 0.001 mol / L, 0.01 mol / L, 0.1 mol / L, 0.3 mol / L, 0.5 mol / L, 0.8 mol / L, 1 mol / L or a range between any two of them.

[0063] It can be understood that by controlling the concentration of the quinone compound in the first solvent to be 0.001-1 mol / L, the polymerization rate of the quinone compound and the sulfide can be controlled.

[0064] In some embodiments, the concentration of the sulfide in the first solvent is 0.001-1 mol / L. Specifically, the concentration of the sulfide in the first solvent can be any one of 0.001 mol / L, 0.01 mol / L, 0.1 mol / L, 0.3 mol / L, 0.5 mol / L, 0.8 mol / L, 1 mol / L or a range between any two of them.

[0065] It can be understood that by controlling the concentration of the sulfide in the first solvent to be 0.001-1 mol / L, the polymerization rate of the quinone compound and the sulfide can be controlled.

[0066] In some embodiments, the heating temperature is 85-300℃, and the heating time is 1-24h. Specifically, the heating temperature can be any one of 85℃, 100℃, 150℃, 200℃, 250℃, 300℃ or a range formed by any two of them; the heating time can be any one of 1h, 5h, 10h, 15h, 20h, 24h or a range formed by any two of them.

[0067] It can be understood that by controlling the heating temperature to be 85-300℃ and the heating time to be 1-24h, the polymerization reaction of the quinone compound and the sulfide can be smoothly carried out.

[0068] In some embodiments, the quinone compound is selected from at least one of benzoquinone derivatives, anthraquinone derivatives, naphthoquinone derivatives, phenanthraquinone derivatives having an electron-donating group, and the electron-donating group is selected from any one of dialkylamino (-NR2), alkylamino (-NHR), amino (-NH2), hydroxyl (-OH), alkoxy (-OR).

[0069] It can be understood that the quinone compound has a large number of strong electron-donating groups, which increases the LUMO (Lower Unoccupied Molecular Orbital, lowest unoccupied molecular orbital) value and is not easy to be reduced, but easy to be oxidized; at the same time, the second solid-state electrolyte has an electron-withdrawing group, which reduces the HOMO (Highest Occupied Molecular Orbital, highest occupied molecular orbital) value and is more likely to be reduced to obtain electrons, so that the LUMO of the quinone compound is much higher than the HOMO value of the second solid-state electrolyte, and the energy level difference between the LUMO energy level of the quinone compound and the HOMO energy level of the second solid-state electrolyte is getting larger (more than 2eV), which can reduce the reactivity between the quinone compound and the first solid-state electrolyte, improve the material utilization rate of the solid-state battery, and thus improve the energy density of the solid-state battery.

[0070] In some embodiments, the sulfide is selected from at least one of sodium sulfide, sodium polysulfide, lithium sulfide, lithium polysulfide, selenium sulfide, cadmium sulfide, aluminum sulfide, and silver sulfide.

[0071] It can be understood that by mixing the quinone compound and the sulfide, the quinone group in the quinone compound can react with the sulfur atom in the sulfide to form a new chemical bond, thereby forming a polysulfone polymer.

[0072] In some embodiments, the first solvent is selected from at least one of N,N-diisopropylethylamine, N,N-dipropylethylamine, N,N-diisopropylethylendiamine, N-isopropylethylendiamine, N-methylpyrrolidone, pyrrolidone, methylpyrrolidone, and 3-pyrrolidone.

[0073] It can be understood that the quinone compound and the sulfide are dissolved in the first solvent, and the first solvent should have good solubility and not have side reactions with the quinone compound and the sulfide.

[0074] In some embodiments, the inert atmosphere is selected from argon (Ar) or nitrogen (N2).

[0075] It can be understood that by polymerizing the quinone compound and the sulfide under an inert atmosphere, the polymerization reaction can be more complete and side reactions can not occur.

[0076] In some embodiments, the negative electrode material comprises a composite binder and silicon powder, and the preparation method of the composite binder comprises:

[0077] The first polymer monomer is dissolved in the second polymer monomer, and after stirring, mixing and reaction, the composite binder is obtained.

[0078] The mass ratio of the first polymer monomer to the second polymer monomer is 0.01-20:80-99.5. Specifically, the mass ratio of the first polymer monomer to the second polymer monomer can be any one of 0.5:99.5, 1:99, 5:95, 10:90, 15:85, 20:80 or a range composed of any two of them.

[0079] It can be understood that the first polymer monomer provides a hard segment, and the second polymer monomer provides a soft segment. The combination of the hard segment of acrylic acid and the soft segment of poly(ethylene glycol) methacrylate makes the composite binder have excellent mechanical strength and elasticity, effectively inhibits the volume expansion of silicon, and reduces the generation of cracks; the ether bond forms a conductive channel for lithium ions, improves the lithium ion conductivity of the electrode, and realizes high electronic conductivity between lithium nanoparticles and the negative electrode current collector; at the same time, a three-dimensional continuous conductive network is formed inside the silicon negative electrode, which promotes the uniform transmission of lithium ions.

[0080] In some embodiments, the first polymer monomer is selected from at least one of lithium acrylate, acrylic acid, and lithium methacrylate.

[0081] In some embodiments, the second polymer monomer is selected from at least one of polyethylene glycol methacrylate, polyethylene glycol diacrylate, polyethylene glycol diacrylate, polyethylene glycol allyl methyl ether, polyethylene glycol methyl ether acrylate, and polyethylene glycol monomaleate.

[0082] In some embodiments, the application also provides a preparation method of a positive electrode, comprising:

[0083] The polythioquinone polymer and the second solid polymer are mixed, ground and dispersed, and pressed under a first pressure to form a positive electrode.

[0084] In some embodiments, the grinding time is 10-20 min. Specifically, the grinding time can be any one of 10 min, 12 min, 14 min, 16 min, 18 min, 20 min or a range between any two of them.

[0085] In some embodiments, the first pressure is 125-130 MPa and the pressing time is 1-3 min. Specifically, the first pressure can be any one of 125 MPa, 126 MPa, 127 MPa, 128 MPa, 129 MPa, 130 MPa or a range between any two of them; the pressing time can be any one of 1 min, 2 min, 3 min or a range between any two of them.

[0086] In some embodiments, the application further provides a method for preparing a negative electrode, comprising:

[0087] dissolving the composite binder and the silicon powder in a third solvent, stirring and mixing to obtain a negative electrode slurry;

[0088] applying the negative electrode slurry to at least one side of the negative electrode current collector and drying to obtain the negative electrode.

[0089] In some embodiments, the third solvent is selected from any one of N, N-dimethylformamide, dimethylformamide, dimethyl sulfoxide, N-methyl pyrrolidone, pyrrolidone, tetrahydrofuran, methyl pyrrolidone, and 3-pyrrolidone.

[0090] In some embodiments, the application further provides a method for preparing a solid-state electrolyte, comprising:

[0091] stirring and mixing lithium atoms (Li), phosphorus atoms (P), sulfur atoms (S), chlorine atoms (Cl), and doping atoms to obtain a mixture;

[0092] pressing the mixture under a second pressure to obtain the solid-state electrolyte.

[0093] In some embodiments, the second pressure is 125-130 MPa and the pressing time is 2-5 min. Specifically, the second pressure can be any one of 125 MPa, 126 MPa, 127 MPa, 128 MPa, 129 MPa, 130 MPa or a range between any two of them; the pressing time can be any one of 2 min, 3 min, 4 min, 5 min or a range between any two of them.

[0094] The application will be described in detail below with reference to specific embodiments.

[0095] Example 1

[0096] Preparation of the positive electrode material: 0.0015 mol / L of 2,3,5,6-tetra( amino) p-benzoquinone and 0.0015 mol / L of sodium sulfide were dissolved in N- methylpyrrolidone and mixed uniformly, and then placed in an Ar atmosphere and heated at 180°C for 6h, washed with propanol, and finally dried at 85°C for 12h to obtain a polyquinone polymer.

[0097] Preparation of the first solid electrolyte: 120mg of Li 5.3 PS 4.3 ClBr 0.7 The first solid electrolyte was formed by pressing at 128MPa for 2min.

[0098] Preparation of the second solid electrolyte: 120mg of Li 5.3 PS 4.3 ClBr 0.7 The second solid electrolyte was formed by pressing at 128MPa for 2min. Preparation of the positive electrode: 130mg of the polyquinone polymer and the second solid electrolyte Li 5.3 PS 4.3 ClBr 0.7 The mass ratio of the polyquinone polymer and the second solid electrolyte Li 5.3 PS 4.3 ClBr 0.7 was 45:55) was mixed and ground in a mortar for 15min to uniformly disperse them; the positive electrode was formed by pressing at 128MPa for 1min.

[0099] Preparation of the composite binder: 1g of lithium acrylate and poly( ethylene glycol) methacrylate (the mass ratio of lithium acrylate and poly( ethylene glycol) methacrylate was 10:90) was mixed, and the lithium acrylate was dissolved in the poly( ethylene glycol) methacrylate, and stirred uniformly until fully polymerized to obtain a composite binder.

[0100] Preparation of the negative electrode: 100mg of the composite binder and silicon powder (the mass ratio of the composite binder and silicon powder was 15:85) was stirred uniformly in N, N-dimethylformamide to obtain a negative electrode slurry.

[0101] The negative electrode slurry was coated on a negative current collector, and dried to obtain a negative electrode.

[0102] Preparation of the full solid-state battery: the positive electrode shell, aluminum, positive electrode, first solid electrolyte, negative electrode, and negative electrode shell were sequentially assembled and sealed in a CR2016 type button cell in an argon-filled glove box to obtain a full solid-state battery.

[0103] The preparation method of Example 2 was the same as that of Example 1, except that the mass ratio of the polyquinone polymer and the second solid electrolyte Li 5.3 PS 4.3 ClBr0.7 at a mass ratio of 50:50.

[0104] Example 3 was prepared according to Example 1, except that the polythioquinone-based polymer and the second solid-state electrolyte Li 5.3 PS 4.3 ClBr 0.7 at a mass ratio of 55:45.

[0105] Example 4 was prepared according to Example 1, except that the second solid-state electrolyte was 120 mg of Li 5.3 PS 4.3 ClI 0.7 , the polythioquinone-based polymer and the second solid-state electrolyte Li 5.3 PS 4.3 ClI 0.7 at a mass ratio of 45:55.

[0106] Example 5 was prepared according to Example 1, except that the second solid-state electrolyte was Li 5.3 PS 4.3 Cl(NO2) 0.7 , the polythioquinone-based polymer and the second solid-state electrolyte Li 5.3 PS 4.3 Cl(NO2) 0.7 at a mass ratio of 45:55.

[0107] Example 6 was prepared according to Example 1, except that the quinone-based compound was 2,3,5,6-tetra(hydroxy) p-benzoquinone.

[0108] Example 7 was prepared according to Example 1, except that the mass ratio of the composite binder and the silicon powder was 10:90.

[0109] Example 8 was prepared according to Example 1, except that the mass ratio of the composite binder and the silicon powder was 5:95;

[0110] Comparative Example 1 was prepared according to Example 1, except that the positive electrode material was 2,3,5,6-tetra(amino) p-benzoquinone.

[0111] Comparative Example 2 was prepared according to Example 1, except that the negative electrode material was silicon powder.

[0112] Comparative Example 3 was prepared according to Example 1, except that the second solid-state electrolyte was Li 5.3 PS 4.3 Cl, the polythioquinone-based polymer and the second solid-state electrolyte Li 5.3 PS 4.3 Cl at a mass ratio of 45:55.

[0113] Test method:

[0114] (1) The test method of the initial efficiency: discharge the battery at 35±3℃ with 0.05C constant current to 1.5V, record the discharge capacity as D1, charge to 3.5V with 0.05C constant current, charge to the cut-off current 0.05C with 3.5V constant voltage, record the charge capacity as C1, then; the initial efficiency = (C1 / D1) x 100%, calculate the ratio of the discharge capacity and the charge capacity to obtain the initial efficiency.

[0115] (2) The first cycle discharge capacity and the capacity retention rate: discharge the battery at 35±3℃ with 0.1C constant current to 1.5V, record the discharge capacity as C1, then charge to 3.5V with 0.1C constant current, charge to the cut-off current 0.05C with 3.5V constant voltage, repeat the charge and discharge steps for N cycles to obtain the discharge capacity C N of the Nth cycle, the capacity retention rate of the Nth cycle = (C N / C1) x 100%, obtain the first cycle discharge capacity and the capacity retention rate.

[0116] Note: if the capacity retention rate is lower than 80% and the coulombic efficiency is lower than 98%, the battery stops the test.

[0117] Table 1 is the parameter setting of examples 1-8 and comparative examples 1-3

[0118]

[0119]

[0120]

[0121] Table 2 is the test results of examples 1-8 and comparative examples 1-3

[0122]

[0123]

[0124] Result analysis:

[0125] Comparing examples 1-8 and comparative example 1, from the test results in table 2, it can be seen that the capacity retention rate of the 70th cycle of the solid-state battery prepared by comparative example 1 is 80.19%, which does not reach the capacity retention rate of the 100th cycle being more than 80%, while the capacity retention rate of the 100th cycle of the solid-state battery prepared by examples 1-8 is about 90% and above, which shows that, by mixing the polythioquinone polymer and the second solid-state electrolyte to prepare the positive electrode material, the reactivity between the quinone compound and the first solid-state electrolyte can be reduced, thereby improving the cycle stability of the solid-state battery.

[0126] Compared with Comparative Example 2, from the test results in Table 2, it can be seen that the capacity retention rate of the solid-state battery prepared by Comparative Example 2 is 85.72% at the 70th cycle, while the capacity retention rate of the solid-state battery prepared by Examples 1-8 is about 90% or more at the 100th cycle, indicating that the negative electrode material is prepared by mixing the composite binder and the silicon powder in the present application, the composite binder provides excellent mechanical strength and elasticity for the negative electrode material, effectively inhibits the volume expansion of silicon, reduces the generation of cracks, and can improve the cycle stability of the solid-state battery.

[0127] Compared with Comparative Example 3, from the test results in Table 2, it can be seen that the capacity retention rate of the solid-state battery prepared by Comparative Example 3 is 87.92% at the 100th cycle, while the capacity retention rate of the solid-state battery prepared by Examples 1-8 is about 90% or more at the 100th cycle, indicating that the present application introduces an electron-accepting group on the second solid-state electrolyte, so that the energy level difference between the LUMO energy level of the quinone compound and the HOMO energy level of the second solid-state electrolyte becomes larger and larger, thereby reducing the reactivity between the quinone compound and the first solid-state electrolyte, and improving the cycle stability of the solid-state battery.

[0128] In summary, although the detailed introduction of the embodiments of the present application is as above, the above embodiments are not intended to limit the present application, and those of ordinary skill in the art should understand that the technical solutions described in the foregoing embodiments can still be modified, or some technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A solid-state battery, characterized by, The application relates to a solid-state battery, comprising: a positive electrode comprising a positive electrode material; a negative electrode comprising a negative electrode current collector and a negative electrode material located on at least one side of the negative electrode current collector; and a first solid-state electrolyte located between the positive electrode and the negative electrode; wherein the negative electrode material comprises a composite binder and silicon powder, the composite binder comprises a first polymer monomer providing a hard segment and a second polymer monomer providing a soft segment, and the composite binder and the silicon powder have a mass ratio of 0.5-20:80-99.5; and the composite binder comprises a polythioquinone polymer, the polythioquinone polymer is prepared by dissolving a quinone compound and a sulfide in a first solvent, mixing uniformly, and then heating; the quinone compound and the sulfide have a mass ratio of 1:1-10; the quinone compound is at least one selected from a benzene quinone derivative, an anthraquinone derivative, a naphthoquinone derivative, and a phenanthraquinone derivative, and the quinone compound has an electron-donating group selected from any one of dialkylamino, alkylamino, amino, hydroxyl, and alkoxy; and the sulfide is at least one selected from sodium sulfide, sodium polysulfide, lithium sulfide, lithium polysulfide, selenium sulfide, cadmium sulfide, aluminum sulfide, and silver sulfide. The application relates to a solid-state battery, comprising: a positive electrode comprising a positive electrode material; a negative electrode comprising a negative electrode current collector and a negative electrode material located on at least one side of the negative electrode current collector; and a first solid-state electrolyte located between the positive electrode and the negative electrode; wherein the positive electrode material comprises a polythioquinone polymer and a second solid-state electrolyte.

4. The preparation method of the solid-state battery according to claim 3, wherein the concentration of the quinone compound in the first solvent is 0.001 mol / L-1 mol / L.

5. The preparation method of the solid-state battery according to claim 3, wherein the concentration of the sulfide in the first solvent is 0.001 mol / L-1 mol / L. The positive electrode material comprises a poly-sulfoquinone polymer and a second solid-state electrolyte, the second solid-state electrolyte has a chemical formula of Li a PS b Cl c R 2 d , wherein 2≤a≤12, 0.5≤b≤8, 0.1≤c≤3, 0.1≤d≤5, R 2 is any one selected from a fluorine atom, a bromine atom, an iodine atom, a nitro group, a cyano group, a sulfonic acid group, an acyl group, and a carboxyl group; and a mass ratio of the poly-sulfoquinone polymer to the second solid-state electrolyte is 20-70:30-80.

6. The preparation method of the solid-state battery according to claim 3, wherein the heating temperature is 85-300 DEG C, and the heating time is 1-24 h.

7. The preparation method of the solid-state battery according to claim 3, wherein the quinone compound is at least one selected from a benzene quinone derivative, an anthraquinone derivative, a naphthoquinone derivative, and a phenanthraquinone derivative, and the quinone compound has an electron-donating group selected from any one of dialkylamino, alkylamino, amino, hydroxyl, and alkoxy.

2. The solid-state battery of claim 1, wherein, Chemical formula of the first solid-state electrolyte: Li X PS Y Cl z R 1 w , wherein 2≤x≤12, 0.5≤y≤8, 0.1≤z≤3, 0≤w≤5, R 1 is selected from any one of a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a nitro group, a cyano group, a sulfonic acid group, an acyl group, a carboxyl group.

3. A method of producing a solid-state battery as claimed in claim 1 or 2, characterized in that 8. The preparation method of the solid-state battery according to claim 3, wherein the sulfide is at least one selected from sodium sulfide, sodium polysulfide, lithium sulfide, lithium polysulfide, selenium sulfide, cadmium sulfide, aluminum sulfide, and silver sulfide.

9. The preparation method of the solid-state battery according to claim 3, wherein the first solvent is at least one selected from N, N-diisopropylethylamine, N, N-dipropylethylamine, N, N-diisopropylethylendiamine, N-isopropylethylendiamine, N-methylpyrrolidone, pyrrolidone, methylpyrrolidone, and 3-pyrrolidone. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 10.The method of claim 3, wherein the inert atmosphere is selected from argon or nitrogen. The negative electrode material comprises a composite binder and silicon powder, and the preparation method of the composite binder comprises:

11. The method of producing a solid-state battery according to claim 3, characterized by, dissolving the first polymer monomer in the second polymer monomer, stirring, mixing, and reacting to obtain the composite binder; The mass ratio of the first polymer monomer to the second polymer monomer is 0.01-20:80-99.

5. 12.The method of claim 11, wherein the first polymer monomer is selected from at least one of lithium acrylate, acrylic acid, and lithium methacrylate. 13.The method of claim 11, wherein the second polymer monomer is selected from at least one of polyethylene glycol methacrylate, polyethylene glycol diacrylate, polyethylene glycol allyl methyl ether, polyethylene glycol methyl ether acrylate, and polyethylene glycol monomaleate. ​ ​ ​

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