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CN-122000438-A - Solid electrolyte membrane, electrolyte pole piece, solid battery, preparation method and power utilization device

CN122000438ACN 122000438 ACN122000438 ACN 122000438ACN-122000438-A

Abstract

The application relates to a solid electrolyte membrane, an electrolyte pole piece, a solid battery, a preparation method and an electric device. The solid electrolyte membrane includes a first electrolyte layer including a sulfide solid electrolyte and a first layer binder including a first binder having a low water absorption rate. The electrolyte sheet comprises an electrode body and a solid electrolyte membrane on at least one side of the electrode body, or comprises an electrode body and a first electrolyte layer on at least one side of the electrode body. The solid-state battery includes at least one of a first electrolyte layer, a solid electrolyte membrane, and an electrolyte sheet. The solid electrolyte membrane, the electrolyte pole piece and the solid battery have obviously reduced hydrogen sulfide release amount in the water-containing environment.

Inventors

  • WU KAI
  • Ling Yuexia
  • HU BOBING
  • YANG DUNJIE
  • WENG WEI

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 electrolyte membrane comprising a first electrolyte layer, the first electrolyte layer comprising a first solid electrolyte and a first layer binder; the first solid electrolyte comprises sulfide solid electrolyte, the first layer of binder comprises a first binder, and the water absorption rate of the first binder is less than or equal to 0.1%.
  2. 2. The solid electrolyte membrane according to claim 1, wherein the first binder comprises a cycloolefin/olefin copolymer, monomer units of the cycloolefin/olefin copolymer comprising cycloolefin-based monomer units and olefin-based monomer units, and a chain skeleton of the cycloolefin/olefin copolymer comprising a cyclic structure provided by the cycloolefin-based monomer units.
  3. 3. A solid electrolyte membrane comprising a first electrolyte layer, the first electrolyte layer comprising a sulfide solid electrolyte and a first layer binder, the first layer binder comprising a first binder; Wherein the first binder comprises a cycloolefin/alkene copolymer, the monomer units of the cycloolefin/alkene copolymer comprise cycloolefin-based monomer units and alkene-based monomer units, and the chain skeleton of the cycloolefin/alkene copolymer comprises a cyclic structure provided by the cycloolefin-based monomer units.
  4. 4. A solid electrolyte membrane according to claim 3, wherein the first binder satisfies one or more of the following characteristics: the chain skeleton of the cycloolefin/alkene copolymer is a carbon skeleton; The cycloolefin/alkene copolymer is an aliphatic polymer; the cyclic structure of the cycloolefin monomer unit comprises one or more of a single ring structure and a multi-ring structure; the number of ring atoms of the ring structure in the cycloolefin monomer unit is 3-30; The alkene monomer units include structural units corresponding to C 2～6 alkene; The pendant groups of the cyclic olefin/alkene copolymer include one or more of C 1～20 aliphatic chains and fluorinated C 1～20 aliphatic chains; In the cycloolefin/alkene copolymer, the mol fraction of the cycloolefin monomer unit is 10% -85%; In the cycloolefin/alkene copolymer, the alkene monomer unit accounts for 15% -90% of the mole fraction; the weight average molecular weight of the cycloolefin/alkene copolymer is 30 kDa-100 kDa.
  5. 5. The solid electrolyte membrane of claim 4 wherein the first binder satisfies one or more of the following characteristics: the number of ring atoms of the ring structure in the cycloolefin monomer unit is 5-20; The cycloolefin monomer unit includes a structural unit corresponding to one or more monomers of norbornene, cyclopentene, cyclohexene and cycloheptene; The alkene monomer units comprise structural units corresponding to one or more monomers of ethylene and propylene, optionally the alkene monomer units comprise structural units corresponding to ethylene; The pendant groups of the cyclic olefin/alkene copolymer include one or more of a C 1～20 alkyl chain and a fluorinated C 1～20 alkyl chain; in the cycloolefin/alkene copolymer, the mol fraction of the cycloolefin monomer unit is 30% -85%; in the cycloolefin/alkene copolymer, the alkene monomer unit accounts for 15% -70% of the mole fraction; the weight average molecular weight of the cycloolefin/alkene copolymer is 30 kDa-50 kDa.
  6. 6. The solid electrolyte membrane according to any one of claims 3 to 5, wherein the cycloolefin/alkene copolymer includes one or more of an (ethylene-cyclopentene) copolymer, an (ethylene-norbornene) random copolymer and an (ethylene-norbornene) alternating copolymer.
  7. 7. The solid electrolyte membrane according to any one of claims 1 to 6, wherein the water absorption of the first binder is less than or equal to 0.05%, optionally the water absorption of the first binder is less than or equal to 0.02%, further optionally the water absorption of the first binder is less than or equal to 0.01%.
  8. 8. The solid electrolyte membrane according to any one of claims 1 to 7, wherein the first electrolyte layer satisfies one or more of the following characteristics: the weight percentage of the first binder in the first layer of binder is 15% -100%, and the first binder is optionally 40% -95%; the weight percentage of the first binder in the first electrolyte layer is 0.3% -6%, and optionally 0.3% -4%; The weight percentage of the sulfide solid electrolyte in the first electrolyte layer is 94% -99.5%.
  9. 9. The solid electrolyte membrane of claim 8 wherein the first electrolyte layer satisfies one or more of the following characteristics: The weight percentage of the first binder in the first layer of binder is 50% -75%; the weight percentage of the first binder in the first electrolyte layer is 0.5% -2%; The weight percentage of the sulfide solid electrolyte in the first electrolyte layer is 95% -98%.
  10. 10. The solid electrolyte membrane according to any one of claims 1 to 9, wherein the first layer of binder further comprises a second binder having a water absorption of greater than or equal to 0.5%, optionally greater than or equal to 1%, further optionally greater than or equal to 2%.
  11. 11. The solid electrolyte membrane of claim 10 wherein the second binder comprises one or more of nitrile rubber, styrene-butadiene rubber, hydrogenated nitrile rubber, natural rubber, etherified cellulose, polymethyl methacrylate, polyethylene oxide methyl vinyl silicone rubber, and derivatives of any of the foregoing, wherein the derivative has a water absorption of greater than or equal to 0.5%; optionally, the second binder comprises at least one of a nitrile rubber and a nitrile rubber derivative, the nitrile rubber derivative comprising a hydrogenated nitrile rubber.
  12. 12. The solid electrolyte membrane according to claim 10 or 11, wherein the first electrolyte layer satisfies one or more of the following characteristics: the weight percentage of the second binder in the first binder is 0% -85%, and 5% -60% can be selected; the sum of the weight percentages of the first binder and the second binder in the first electrolyte layer is 0.5% -6%; the weight of the first binder accounts for 15% -100% of the sum of the weight of the first binder and the weight of the second binder, and is optionally 40% -95%; the weight of the second binder accounts for 0% -85%, optionally 5% -60% of the total weight of the first binder and the second binder.
  13. 13. The solid electrolyte membrane of claim 12 wherein the first electrolyte layer satisfies one or more of the following characteristics: The weight percentage of the first binder in the first layer of binder is 50% -75%; The weight percentage of the second binder in the first binder is 25% -50%; the weight percentage of the first binder in the first electrolyte layer is 0.5% -2%; The sum of the weight percentages of the first binder and the second binder in the first electrolyte layer is 2% -5%; the weight percentage of the sulfide solid electrolyte in the first electrolyte layer is 95% -98%; The weight of the first binder accounts for 50% -75% of the sum of the weight of the first binder and the weight of the second binder; the weight of the second binder accounts for 25% -50% of the sum of the weight of the first binder and the weight of the second binder.
  14. 14. The solid electrolyte membrane according to any one of claims 1 to 8, wherein the first layer of binder comprises a cyclic olefin/alkene copolymer, and further comprises one or more of nitrile rubber, styrene-butadiene rubber, hydrogenated nitrile rubber, natural rubber, polyvinylidene fluoride, etherified cellulose, polymethyl methacrylate, and polyoxyethylene methyl vinyl silicone rubber.
  15. 15. The solid electrolyte membrane according to any one of claims 1 to 14, wherein the sulfide solid electrolyte comprises one or more of LGPS-type sulfide electrolyte, silver germanium sulfide ore-type sulfide electrolyte, lithium sulfide phosphorus pentasulfide complex-type sulfide electrolyte, and thio-LISICON sulfide electrolyte.
  16. 16. The solid electrolyte membrane of claim 15 wherein the sulfide solid electrolyte comprises Li 6-x PS 5-x Cl 1+x , wherein 0≤x≤0.9.
  17. 17. The solid electrolyte membrane according to any one of claims 1 to 16, wherein the thickness of the first electrolyte layer is 15 to 75 μm, optionally 25 to 50 μm.
  18. 18. An electrolyte pole piece, which is characterized by comprising an electrode body and a solid electrolyte membrane positioned on at least one side of the electrode body, wherein the solid electrolyte membrane is the solid electrolyte membrane according to any one of claims 1-17; or the electrolyte pole piece comprises an electrode body and a first electrolyte layer positioned on at least one side of the electrode body, wherein the first electrolyte layer is defined in any one of claims 1-17.
  19. 19. The electrolyte sheet according to claim 18, wherein the electrolyte sheet is an electrolyte negative sheet and the electrode body is a negative body; Optionally, the negative electrode body includes a negative electrode current collector and a negative electrode active material layer located on at least one side of the negative electrode current collector, and the first electrolyte layer is located on a side of the negative electrode active material layer away from the negative electrode current collector.
  20. 20. A solid-state battery comprising at least one of the first electrolyte layer defined in any one of claims 1 to 17, the solid electrolyte membrane defined in any one of claims 1 to 17, and the electrolyte sheet defined in claim 18 or 19.

Description

Solid electrolyte membrane, electrolyte pole piece, solid battery, preparation method and power utilization device Technical Field The application relates to the technical field of solid batteries, in particular to a solid electrolyte membrane, an electrolyte pole piece, a solid battery, a preparation method and an electric device, and further relates to the solid electrolyte membrane and the preparation method thereof, the electrolyte pole piece, the solid battery and the preparation method thereof and the electric device. Background The statements herein merely provide background information related to the present disclosure and may not necessarily constitute prior art. The solid-state battery introduces nonflammable solid electrolyte to replace organic electrolyte in the traditional liquid secondary battery, so that the safety of the battery is greatly improved. Among the numerous solid electrolyte materials, sulfide solid electrolyte is one of the most promising solid electrolyte materials for practical use and industrialization due to its extremely high ionic conductivity and excellent mechanical properties. The chemical stability problem under the water-containing atmosphere is one of the most serious problems faced by sulfide solid electrolyte, and water in the air reacts with sulfide to generate highly toxic and harmful gas hydrogen sulfide, so that the degradation of sulfide is further accelerated, and the practical application of the sulfide solid electrolyte is severely restricted. Disclosure of Invention In view of the above, the present application provides a solid electrolyte membrane, an electrolyte sheet, a solid battery, a manufacturing method and an electrical device, and further provides a solid electrolyte membrane and a manufacturing method thereof, an electrolyte sheet, a solid battery and a manufacturing method thereof, and an electrical device, according to various embodiments and various examples of the present application. The solid electrolyte membrane, the electrolyte pole piece and the solid battery have obviously reduced hydrogen sulfide release amount in the water-containing environment. In a first aspect, the present application provides a solid electrolyte membrane comprising a first electrolyte layer comprising a sulfide solid electrolyte and a first layer binder, the first layer binder comprising a first binder; the first binder satisfies one or more of the following characteristics: (t 1) the water absorption rate of the first binder is less than or equal to 0.1%; (t 2) the first binder comprises a cycloolefin/olefin copolymer, the monomer unit of which comprises a cycloolefin monomer unit and an olefin monomer unit, and the chain skeleton of which comprises a cyclic structure provided by the cycloolefin monomer unit. In some embodiments, a solid electrolyte membrane is provided that includes a first electrolyte layer including a first solid electrolyte and a first layer binder; the first solid electrolyte comprises sulfide solid electrolyte, the first layer of binder comprises a first binder, and the water absorption rate of the first binder is less than or equal to 0.1%. In some embodiments, the first binder includes a cyclic olefin/alkene copolymer, the monomer units of the cyclic olefin/alkene copolymer including cyclic olefin monomer units and alkene monomer units, and the chain backbone of the cyclic olefin/alkene copolymer including a cyclic structure provided by the cyclic olefin monomer units. In some embodiments, a solid electrolyte membrane is provided that includes a first electrolyte layer including a sulfide solid electrolyte and a first layer binder including a first binder; Wherein the first binder comprises a cycloolefin/alkene copolymer, the monomer units of the cycloolefin/alkene copolymer comprise cycloolefin-based monomer units and alkene-based monomer units, and the chain skeleton of the cycloolefin/alkene copolymer comprises a cyclic structure provided by the cycloolefin-based monomer units. The first binder is a binder having a relatively low water absorption, and may have a water absorption of 0.1% or less. The first binder may include a cycloolefin/olefin copolymer having a relatively low water absorption rate, and for example, may include a cycloolefin/olefin copolymer having a water absorption rate of 0.01% or less. By introducing the first binder having a low water absorption rate into the phase solid electrolyte membrane containing the sulfide solid electrolyte, the absorption of moisture by the solid electrolyte membrane can be reduced, the probability of contact reaction between the sulfide solid electrolyte and water can be reduced, the decomposition of the sulfide solid electrolyte can be reduced or suppressed, and the release amount of hydrogen sulfide in the aqueous environment (such as air) of the solid electrolyte membrane can be significantly reduced. Further, the release amount of hydrogen sulfide in an aqueous environment (such as