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CN-122000420-A - Solid-state battery, positive electrode sheet, positive electrode active material, preparation method, power utilization device and application

CN122000420ACN 122000420 ACN122000420 ACN 122000420ACN-122000420-A

Abstract

The application relates to a solid-state battery, a positive electrode plate, a positive electrode active material, a preparation method, an electric device and application, wherein the solid-state battery comprises a positive electrode layer, the positive electrode layer comprises a positive electrode active material layer, the positive electrode active material layer comprises a positive electrode active material and a sulfide electrolyte, the positive electrode active material comprises positive electrode composite coated particles, the positive electrode composite coated particles comprise a core containing a lithium-rich manganese-based positive electrode material, a first coating layer coated on at least part of the surface of the core and a second coating layer coated on at least part of the surface of the first coating layer, the first coating layer comprises a first coating material, the first coating material comprises a metal oxide with the electronic conductivity of more than or equal to 1S/cm, the second coating layer comprises a second coating material, and the second coating material comprises a lithium-indium-based halide, wherein the atomic mole ratio of lithium element, indium element and halogen in the lithium-indium-based halide is a:b, c, a is more than or equal to 2 and less than or equal to 3, and more than or equal to 0 and less than or equal to 4c and less than or equal to 6. The discharge capacity and the cycle performance of the solid-state battery are effectively improved.

Inventors

  • WU KAI
  • Shao Qinong
  • ZHANG HONGTU
  • Zheng Chuanzuo
  • HUANG JINFENG
  • HU BOBING
  • NING ZIYANG

Assignees

  • 宁德时代新能源科技股份有限公司

Dates

Publication Date
20260508
Application Date
20241108

Claims (20)

  1. 1. A solid-state battery comprising a positive electrode layer, the positive electrode layer comprising a positive electrode active material and a sulfide electrolyte, the positive electrode active material comprising positive electrode composite coated particles, the positive electrode composite coated particles comprising: a core comprising a lithium-rich manganese-based positive electrode material; A first coating layer coated on at least part of the surface of the inner core, the first coating layer comprising a first coating material comprising a metal oxide having an electron conductivity of 1S/cm or more, and The second coating layer is coated on at least part of the surface of the first coating layer, and comprises a second coating material, wherein the second coating material comprises lithium indium-based halide, and the atomic mole ratio of lithium element, indium element and halogen in the lithium indium-based halide is a, b is b, a is more than or equal to 2 and less than or equal to 3, b is more than or equal to 0 and less than or equal to 1, and c is more than or equal to 4 and less than or equal to 6.
  2. 2. The solid state battery of claim 1, wherein the lithium indium-based halide has a chemical formula of Li a In b Q x Cl c , 2≤a≤3, 0≤b≤1, 0≤x <1, 0≤b+x≤1, 4≤c≤ 6,Q, including at least one of Sc, Y and Zr.
  3. 3. The solid state battery of any of claims 1 to 2, wherein the first cladding material comprises one or more of Li 2 RuO 3 、Fe 3 O 4 , sb doped SnO 2 , sn doped In 2 O 3 and Al doped ZnO.
  4. 4. The solid state battery of claim 3, wherein the first cladding material comprises at least one of the following features (1) - (3): (1) In the Sb-doped SnO 2 , taking the total atomic number of Sb and Sn as a reference, the atomic percentage of Sb is recorded as w1,0< w1 is less than or equal to 10at%; (2) In 2 O 3 doped with Sn, the atomic percentage of Sn is recorded as w2,0< w2 is less than or equal to 20at% based on the total atomic number of Sn and In; (3) In Al-doped ZnO, the atomic percentage of Al is recorded as w3,0< w3≤10at% based on the total atomic number of Al and Zn.
  5. 5. The solid-state battery according to any one of claims 1 to 4, wherein the first coating layer has at least one of the following features (1) - (2): (1) The mass ratio of the first coating material contained in the first coating layer in the positive electrode composite coating particles is 0.1% -5%; (2) The thickness of the first coating layer is 0.1nm-50nm.
  6. 6. The solid-state battery according to any one of claims 1 to 5, wherein the first coating layer has at least one of the following features (1) - (2): (1) The mass ratio of the first coating material contained in the first coating layer in the positive composite coating particles is 0.1% -3%; (2) The thickness of the first coating layer is 0.1nm-10nm.
  7. 7. The solid-state battery according to any one of claims 1 to 6, wherein the second coating layer has at least one of the following features (1) - (2): (1) The mass ratio of the second coating material contained in the second coating layer in the positive electrode composite coating particles is 0.1% -5%; (2) The thickness of the second coating layer is 0.1nm-50nm.
  8. 8. The solid-state battery according to any one of claims 1 to 7, wherein the second coating layer has at least one of the following features (1) - (2): (1) The mass ratio of the second coating material contained in the second coating layer in the positive electrode composite coating particles is 0.1% -3%; (2) The thickness of the second coating layer is 0.1nm-10nm.
  9. 9. The solid state battery of any of claims 1 to 8, wherein the lithium-rich manganese-based positive electrode material is a layered lithium-rich manganese-based positive electrode material.
  10. 10. The solid-state battery according to any one of claims 1 to 9, wherein the chemical formula of the lithium-rich manganese-based positive electrode material satisfies xLi 2 MnO 3 ·(1-x)LiMO 2 , and the M element includes one or several elements of Ni, co, mn, cr, fe, al, nb, zr, mo and Ta, 0< x <1.
  11. 11. The solid-state battery according to any one of claims 1 to 10, wherein the Dv50 of the positive electrode composite coated particles is 0.5 μm to 15 μm.
  12. 12. The solid-state battery according to any one of claims 1 to 11, wherein the Dv50 of the positive electrode composite coated particles is 1 μm to 10 μm.
  13. 13. The solid state battery according to any one of claims 1 to 12, wherein the sulfide electrolyte has a Dv50 of 0.001 μm-20 μm.
  14. 14. The solid state battery according to any one of claims 1 to 13, wherein the sulfide electrolyte has a Dv50 of 0.05 μm-1 μm.
  15. 15. The solid state battery of any of claims 1 to 14, wherein the sulfide electrolyte comprises one or more of a sulfur silver germanium ore type sulfide electrolyte, a lithium germanium phosphorus sulfur type sulfide electrolyte, and a lithium phosphorus sulfide pentasulfide complex type sulfide electrolyte.
  16. 16. The solid state battery of claim 15, wherein the sulfide electrolyte comprises at least one of the following features (1) - (3): (1) The chemical formula of the sulfur silver germanium ore type sulfide electrolyte meets Li 6±s P 1-j A j S 5±s-t B t X 1±s , j is more than or equal to 0 and less than or equal to 1, t is more than or equal to 0 and less than or equal to 1, s is more than or equal to 0 and less than or equal to 1, A element comprises one or more elements of Ge, si, sn and Sb, B element comprises one or more elements of O, se and Te, and X element is one or more elements of Cl, br, I and F; (2) The chemical formula of the lithium germanium phosphorus sulfur sulfide electrolyte meets the requirement that Li 10±δ Ge 1-g G g P 2-q Q q S 12-w W w ,0≤δ<1,0≤g≤1,0≤q≤2,0≤w<1,G elements comprise one or more elements of Si and Sn, Q elements comprise Sb, and W elements are one or more elements selected from O, se, te, cl, br, I and F; (3) The chemical formula of the lithium-phosphorus sulfide pentasulfide compound sulfide electrolyte meets the requirement that (100-u-v)Li 2 S·uP 2 S 5 ·vM m N n ,0<u<100,0≤v<100,0≤u+v<100,0≤m<4,0≤n<6,M elements are one or more elements selected from Li, B, ge, si, sn and Sb, and N elements are one or more elements selected from S, se, te, O, cl, br, I and F.
  17. 17. The solid-state battery according to any one of claims 1 to 16, characterized in that the solid-state battery has at least one of the following features (1) - (2): (1) The mass ratio of the positive electrode active material in the positive electrode active material layer is 50% -99%; (2) The sulfide electrolyte accounts for 0.1-50% of the positive electrode active material layer by mass.
  18. 18. The solid-state battery according to any one of claims 1 to 17, characterized in that the solid-state battery has at least one of the following features (1) - (2): (1) The mass ratio of the positive electrode active material in the positive electrode active material layer is 70% -95%; (2) The sulfide electrolyte accounts for 5-30% of the positive electrode active material layer by mass.
  19. 19. The solid state battery according to any one of claims 1 to 18, wherein the solid state battery is a lithium ion all solid state battery.
  20. 20. The positive electrode plate is characterized by comprising a positive electrode active material layer, wherein the positive electrode active material layer comprises a positive electrode active material and a sulfide electrolyte, the positive electrode active material comprises positive electrode composite coating particles, and the positive electrode composite coating particles comprise: a core comprising a lithium-rich manganese-based positive electrode material; A first coating layer coated on at least part of the surface of the core, the first coating layer comprising a first coating material having an electron conductivity of 1S/cm or more, and The second coating layer is coated on at least part of the surface of the first coating layer, and comprises a second coating material, wherein the second coating material comprises lithium indium-based halide, and the atomic mole ratio of lithium element, indium element and halogen in the lithium indium-based halide is a, b is b, a is more than or equal to 2 and less than or equal to 3, b is more than or equal to 0 and less than or equal to 1, and c is more than or equal to 4 and less than or equal to 6.

Description

Solid-state battery, positive electrode sheet, positive electrode active material, preparation method, power utilization device and application Technical Field The application relates to the technical field of solid-state batteries, in particular to a solid-state battery, a positive electrode plate, a positive electrode active material, a preparation method, an electric device and application. Background The statements herein merely provide background information related to the present disclosure and may not necessarily constitute prior art. The solid-state battery adopts a nonflammable solid electrolyte to replace organic electrolyte in the traditional liquid-state battery, so that the safety of the battery is greatly improved, and the battery is considered to be a new generation battery closest to industrialization. However, when the lithium-rich manganese-based positive electrode material is applied to an all-solid-state battery, the capacity of the solid-state battery is low and the cycle performance is poor. Disclosure of Invention The application provides a solid-state battery, a positive electrode plate, a positive electrode active material, a preparation method, an electric device and application. In order to achieve the above object, a first aspect of the present application provides a solid-state battery including a positive electrode layer including a positive electrode active material and a sulfide electrolyte, the positive electrode active material including positive electrode composite coated particles including: a core comprising a lithium-rich manganese-based positive electrode material; A first coating layer coated on at least part of the surface of the inner core, the first coating layer comprising a first coating material comprising a metal oxide having an electron conductivity of 1S/cm or more, and The second coating layer is coated on at least part of the surface of the first coating layer, and comprises a second coating material, wherein the second coating material comprises lithium indium-based halide, and the atomic mole ratio of lithium element, indium element and halogen in the lithium indium-based halide is a, b is b, a is more than or equal to 2 and less than or equal to 3, b is more than or equal to 0 and less than or equal to 1, and c is more than or equal to 4 and less than or equal to 6. Therefore, the positive electrode active material adopted by the positive electrode active material layer of the solid-state battery comprises an inner core containing the lithium-rich manganese-based positive electrode material and a composite coating layer comprising a first coating layer and a second coating layer, wherein the coating material contained in the first coating layer comprises metal oxide with higher electronic conductivity (for example, more than or equal to 1S/cm), the metal oxide, the lithium-rich manganese-based positive electrode material and sulfide electrolyte have better stability, the metal oxide, the lithium-rich manganese-based positive electrode material and the sulfide electrolyte can be used as the coating layer to effectively improve the electronic conductivity of the positive electrode active material, and meanwhile, part of metal elements in the metal oxide can be doped into crystal lattices of the lithium-rich manganese-based positive electrode material, so that the structural stability of the lithium-rich manganese-based positive electrode material is improved. The second coating material containing lithium indium-based halide in the second coating layer has higher ion conductivity (for example >1 mS/cm), and the interfacial ion conduction of the positive electrode active material can be effectively improved by using the second coating material as the coating layer. Therefore, by forming the composite coating layer on the surface of the lithium-rich manganese-based positive electrode material, the electronic conductivity and the ionic conductivity of the positive electrode active material can be remarkably improved, so that the utilization rate of the negative ion redox of the positive electrode active material is improved, and the discharge capacity of the positive electrode active material in the solid-state battery is improved. Meanwhile, in the charging process, the oxidation process from O 2- to O 22- is carried out on the lithium-rich manganese-based positive electrode material, so that the discharge capacity of the positive electrode active material in the solid-state battery is further improved. in the oxidation process from O 2- to O 22-, O 22- can be stabilized by In element In the second coating material to form an In-O bond, so that the release of oxygen In the lithium-rich manganese-based cathode material is avoided. In-O bond can be reduced into In-Cl bond In the discharging process, so that oxygen release can be inhibited continuously In the subsequent charge-discharge cycle. Therefore, the coupling relation exists between the oxygen ion