Search

EP-4738508-A1 - SOLID ELECTROLYTE MEMBRANE AND PREPARING METHOD AND APPLICATION THEREOF

EP4738508A1EP 4738508 A1EP4738508 A1EP 4738508A1EP-4738508-A1

Abstract

The disclosure proposes a solid electrolyte membrane and a preparation method and an application thereof. The solid electrolyte membrane includes a binder and a sulfide solid electrolyte. The sulfide solid electrolyte has a molecular formula of Li f P 1-g E g S w O g Q z , wherein, 5<f<10; 0<g<1, 3<w<6, 4<w+g<6, 0<z<2; E is selected from one or more of Mg, Ca, Sr, Ba, Zn, Cr, Sn or Pb; Q is selected from one or more of Cl, Br or I. Ionic conductivity of the solid electrolyte membrane is 1×10 -3 S/cm to 2×10 -2 S/cm. Through the solid electrolyte membrane and the preparation method and the application thereof proposed by the disclosure, the stability of the conductivity of the solid electrolyte membrane may be enhanced, the air stability may be enhanced, and the lifetime and safety of all-solid-state lithium-ion batteries may be improved.

Inventors

  • YU, LE
  • WU, MING

Assignees

  • AESC Japan Ltd.

Dates

Publication Date
20260506
Application Date
20250922

Claims (11)

  1. A solid electrolyte membrane, comprising: a binder; and a sulfide solid electrolyte, characterized in that , the sulfide solid electrolyte has a molecular formula of Li f P 1-g E g S w O g Q z ; wherein, 5<f<10; 0<g<1, 3<w<6, 4<w+g<6, 0<z<2; E is selected from one or more of Mg, Ca, Sr, Ba, Zn, Cr, Sn or Pb; Q is selected from one or more of Cl, Br or I, wherein an ionic conductivity of the solid electrolyte membrane being 1×10 -3 S/cm to 2×10 -2 S/cm.
  2. The solid electrolyte membrane according to claim 1, wherein E is Mg.
  3. The solid electrolyte membrane according to claim 1, wherein Q is Cl; a value range of g is 0.01≤g≤0.1.
  4. The solid electrolyte membrane according to claim 1, wherein a thickness of the solid electrolyte membrane is 1µm to 200µm.
  5. The solid electrolyte membrane according to claim 1, wherein a mass ratio of the binder to the sulfide solid electrolyte is 0.1:99.9 to 10:90.
  6. A preparing method of the solid electrolyte membrane according to any one of claims 1 to 5, comprising: according to the molecular formula of the sulfide solid electrolyte, mixing raw materials uniformly according to stoichiometry, placing the mixed raw materials in a ball mill jar for ball milling to obtain a sulfide solid electrolyte precursor powder; calcining the sulfide solid electrolyte precursor powder at a preset temperature to obtain the sulfide solid electrolyte; and mixing the sulfide solid electrolyte with the binder, and obtaining the solid electrolyte membrane through a dry method or a wet method.
  7. The preparing method of the solid electrolyte membrane according to claim 6, wherein a Li source of the mixed raw materials is selected from one or more of LiCl, LiBr, LiI or Li 2 S; a P source of the mixed raw materials is selected from one or more of elemental P, P 2 S 5 , P 4 S 6 , PCl 5 or PBr 5 ; a E source of the mixed raw materials is selected from one or more of oxide of E or sulfide of E; a S source of the mixed raw materials is selected from one or more of elemental S, Li 2 S, P 2 S 5 , P 4 S 6 , MgS, CaS, SrS, BaS, ZnS, CrS, SnS or PbS; a Q source of the mixed raw materials is selected from one or more of LiCl, PCl 5 , LiBr, PBr 5 , LiI or I 2 ; the O element in the molecular formula comes from the oxide of E.
  8. The preparing method of the solid electrolyte membrane according to claim 6, wherein when the solid electrolyte membrane is prepared by the dry method, the binder is a first binder, the first binder is selected from one or more of polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer, fluorinated ethylene propylene copolymer, perfluoroalkoxy resin, polychlorotrifluoroethylene, ethylene-chlorotrifluoroethylene copolymer, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer or polyvinylidene fluoride-chlorotrifluoroethylene copolymer.
  9. The preparing method of the solid electrolyte membrane according to claim 6, wherein when the solid electrolyte membrane is prepared by the wet method, the binder is a second binder, the second binder is selected from one or more of polyvinylidene fluoride, carboxymethyl cellulose, styrene-butadiene rubber, polyvinylpyrrolidone, polymethyl methacrylate, polyacrylonitrile, polyacrylic acid, polyurethane, polyvinyl alcohol, sodium alginate, ethylene-propylene-diene monomer, styrene-butadiene rubber, fluororubber, β-cyclodextrin polymer, polypropylene emulsion, polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer, fluorinated ethylene propylene copolymer, perfluoroalkoxy resin, polychlorotrifluoroethylene, ethylene-chlorotrifluoroethylene copolymer, polyvinylidene fluoride-hexafluoropropylene copolymer or polyvinylidene fluoride-chlorotrifluoroethylene copolymer.
  10. An all-solid-state lithium-ion battery, comprising: a cathode electrode sheet, the cathode electrode sheet comprising halide solid electrolyte, the halide solid electrolyte comprising Li 2.35 Zr 0.65 Fe 0.35 Cl 5 Br 0.5 I 0.5 ; an anode electrode sheet; and a solid electrolyte membrane, the solid electrolyte membrane being disposed between the adjacent cathode electrode sheet and the anode electrode sheet, the solid electrolyte membrane being selected from the solid electrolyte membrane according to any one of claims 1 to 5.
  11. An electronic device, comprising the all-solid-state lithium-ion battery according to claim 10.

Description

BACKGROUND Technical Field This disclosure relates to the technical field of lithium-ion batteries, and specifically relates to a solid electrolyte membrane and a preparation method and an application thereof. Description of Related Art With the rapid development of new energy technology, lithium-ion batteries are widely applied due to their advantages such as high energy density and long cycle lifetime. However, traditional lithium-ion batteries use liquid electrolyte, which has safety hazards such as electrolyte leakage and combustion. To overcome these disadvantages, solid electrolyte materials have received widespread attention. Among them, sulfide solid electrolyte is highly favored due to its high ionic conductivity and good mechanical performance. Currently, various sulfide solid electrolyte materials have been developed, such as Li10GeP2S12 or Li6PS5Cl. However, most current sulfide electrolytes have poor chemical stability and are prone to decomposition in air, generating toxic hydrogen sulfide gas, which causes harm to the environment and human health, and the production conditions require strict requirements, increasing production complexity and cost. In addition, the interface compatibility between sulfide solid electrolyte and electrode materials also needs to be improved, with large interface impedance, affecting battery performance. SUMMARY The disclosure proposes a solid electrolyte membrane and a preparation method and an application thereof. Through the solid electrolyte membrane and the preparation method and the application thereof proposed by the disclosure, the stability of the conductivity of the solid electrolyte membrane may be enhanced, the air stability may be enhanced, electrolyte/active material interface properties may be improved, and the lifetime and safety of all-solid-state lithium-ion batteries may be improved. To solve the above technical problems, the disclosure proposes a solid electrolyte membrane, at least including a binder; and a sulfide solid electrolyte. The sulfide solid electrolyte has a molecular formula of LifP1-gEgSwOgQz; wherein, 5<f<10; 0<g<1, 3<w<6, 4<w+g<6, 0<z<2; E is selected from one or more of Mg, Ca, Sr, Ba, Zn, Cr, Sn or Pb; Q is selected from one or more of Cl, Br or I. Ionic conductivity of the solid electrolyte membrane is 1×10-3S/cm to 2×10-2S/cm. In one embodiment of the disclosure, E is Mg. In one embodiment of the disclosure, Q is selected from Cl; a value range of g is 0.01≤g≤0.1. In one embodiment of the disclosure, a thickness of the solid electrolyte membrane is 1µm to 200µm. In one embodiment of the disclosure, a mass ratio of the binder to the sulfide solid electrolyte is 0.1:99.9 to 10:90. The disclosure also provides a preparing method of the solid electrolyte membrane described above, including the following steps. According to a chemical formula of the sulfide solid electrolyte, raw materials are mixed uniformly according to stoichiometry, placed in a ball mill jar for ball milling to obtain sulfide solid electrolyte precursor powder. The sulfide solid electrolyte precursor powder is calcined at a preset temperature to obtain the sulfide solid electrolyte. The sulfide solid electrolyte is mixed with the binder, and the solid electrolyte membrane is obtained through dry method preparation or wet method preparation. In one embodiment of the disclosure, the Li source is selected from one or more of LiCl, LiBr, LiI or Li2S; the P source is selected from one or more of elemental P, P2S5, P4S6, PCl5 or PBr5; the E source is selected from one or more of oxide of E or sulfide of E; the S source is selected from one or more of elemental S, Li2S, P2S5, P4S6, MgS, CaS, SrS, BaS, ZnS, CrS, SnS or PbS; the Q source is selected from one or more of LiCl, PCl5, LiBr, PBr5, LiI or I2; the O element in the chemical formula comes from the oxide of E. In one embodiment of the disclosure, when the solid electrolyte membrane is prepared by dry method, the binder is selected from a first binder, the first binder is selected from one or more of polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer, fluorinated ethylene propylene copolymer, perfluoroalkoxy resin, polychlorotrifluoroethylene, ethylene-chlorotrifluoroethylene copolymer, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer or polyvinylidene fluoride-chlorotrifluoroethylene copolymer. In one embodiment of the disclosure, when the solid electrolyte membrane is prepared by wet method, the binder is selected from a second binder, the second binder is selected from one or more of polyvinylidene fluoride, carboxymethyl cellulose, styrene-butadiene rubber, polyvinylpyrrolidone, polymethyl methacrylate, polyacrylonitrile, polyacrylic acid, polyurethane, polyvinyl alcohol, sodium alginate, ethylene-propylene-diene monomer, styrene-butadiene rubber, fluororubber, β-cyclodextrin polymer, polypropylene emulsion, polytetrafluoroethylene, ethylene-tetrafluoroethylene copo