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EP-4738473-A1 - SULFIDE SOLID ELECTROLYTE, METHOD OF PREPARING THE SAME AND APPLICATION

EP4738473A1EP 4738473 A1EP4738473 A1EP 4738473A1EP-4738473-A1

Abstract

A sulfide solid electrolyte, a method of preparing the same, and an application are provided. A molecular formula of the sulfide solid electrolyte is Li f P 1-g E g S w O g Q z , where, 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, and Q is selected from one or more of Cl, Br, or I. Through the sulfide solid electrolyte, the method of preparing the same, and the application provided by the disclosure, the stability of ionic conductivity of the sulfide solid electrolyte is increased, the air stability is enhanced, and the electrolyte/active material interface properties are improved, so that the service life and safety of an all-solid-state lithium-ion battery are increased.

Inventors

  • YU, LE
  • WU, MING

Assignees

  • AESC Japan Ltd.

Dates

Publication Date
20260506
Application Date
20250822

Claims (10)

  1. A sulfide solid electrolyte, having 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, and Q is selected from one or more of Cl, Br, or I.
  2. The sulfide solid electrolyte according to claim 1, wherein E is selected from Mg, and Q is selected from Cl.
  3. The sulfide solid electrolyte according to claim 1, wherein a value range of g is 0.01≤g≤0.1.
  4. A method of preparing the sulfide solid electrolyte according to any one of claims 1 to 3, comprising: according to a chemical formula of the sulfide solid electrolyte, mixing a Li source, a P source, an E source, a S source, and a Q source according to a stoichiometric ratio, placing the mixture in a ball mill jar for ball milling to obtain sulfide solid electrolyte precursor powder; and calcining the sulfide solid electrolyte precursor powder at a predetermined temperature to obtain the sulfide solid electrolyte.
  5. The method of preparing the sulfide solid electrolyte according to claim 4, wherein the Li source is selected from one or more of LiCl, LiBr, LiI, or Li 2 S, the P source is selected from one or more of elemental P, P 2 S 5 , P 4 S 6 , PCl 5 , or PBr 5 , 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, Li 2 S, P 2 S 5 , P 4 S 6 , MgS, CaS, SrS, BaS, ZnS, CrS, SnS, or PbS, the Q source is selected from one or more of LiCl, PCl 5 , LiBr, PBr 5 , LiI, or I 2 , and the O element in the chemical formula is derived from the oxide of E.
  6. The method of preparing the sulfide solid electrolyte according to claim 4, wherein ball milling time is 1h to 48h, a ball milling rotation speed is 50 rpm to 1,500 rpm, and a ball-to-material ratio is 1:1 to 100:1.
  7. The method of preparing the sulfide solid electrolyte according to claim 4, wherein the predetermined temperature is 400°C to 600°C, and time of the calcining treatment is 1h to 18h.
  8. An all-solid-state lithium-ion battery, at least comprising: a positive electrode sheet comprising a halide solid electrolyte comprising Li 2.35 Zr 0.65 Fe 0.35 Cl 5 Br 0.5 I 0.5 ; a negative electrode sheet; and a solid electrolyte membrane disposed between the adjacent positive electrode sheet and negative electrode sheet, wherein the solid electrolyte membrane comprises the sulfide solid electrolyte according to any one of claims 1 to 3.
  9. The all-solid-state lithium-ion battery according to claim 8, wherein the positive electrode sheet comprises a positive active material selected from one or more of lithium nickel cobalt manganese oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel manganese oxide, lithium cobalt oxide, or lithium nickel cobalt aluminum oxide.
  10. An electronic apparatus, comprising the all-solid-state lithium-ion battery according to any one of claims 8 to 9.

Description

BACKGROUND Technical Field The disclosure relates to the technical field of lithium-ion batteries, and specifically relates to a sulfide solid electrolyte, a method of preparing the same, and an application. Description of Related Art Lithium-ion batteries, as the mainstream secondary batteries at present, is widely used in electric vehicles, electronic products, and other fields. However, conventionally, a lithium-ion battery adopts flammable organic liquid electrolyte, which may pose safety hazards such as electrolyte leakage and flammability, so further development of lithium-ion batteries is limited. In order to overcome the safety problems found in the organic liquid electrolyte, solid electrolyte has become a key research direction for next-generation battery technology. At present, most of the currently-available sulfide electrolytes exhibit poor chemical stability. Further, sulfides are prone to side reactions with electrode materials, so irreversible capacity loss may be generated, and the cycle performance of the battery is thereby seriously affected. In addition, sulfides are also prone to react with components in air such as water and oxygen, leading to deterioration of electrolyte performance, etc. These problems seriously limit the promotion of sulfide solid electrolyte in practical applications. SUMMARY The disclosure provides a sulfide solid electrolyte, a method of preparing the same, and an application through which stability of ionic conductivity of the sulfide solid electrolyte is increased, air stability is enhanced, and electrolyte/active material interface properties are improved, so that the service life and safety of an all-solid-state lithium-ion battery are increased. To address the above technical problems, the disclosure provides a sulfide solid electrolyte having a molecular formula of LifP1-gEgSwOgQz, where, 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, and Q is selected from one or more of Cl, Br, or I. In an embodiment of the disclosure, E is selected from Mg, and Q is selected from Cl. In an embodiment of the disclosure, a value range of g is 0.01<g<0.1. The disclosure further provides a method of preparing the sulfide solid electrolyte, and the method includes the following steps. According to a chemical formula of the sulfide solid electrolyte, a Li source, a P source, an E source, a S source, and a Q source are mixed according to a stoichiometric ratio, and the mixture is 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 predetermined temperature to obtain the sulfide solid electrolyte. In an 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, and the Q source is selected from one or more of LiCl, PCl5, LiBr, PBr5, LiI, or I2. The O element in the chemical formula is derived from the oxide of E. In an embodiment of the disclosure, ball milling time is 1h to 48h, a ball milling rotation speed is 50 rpm to 1,500 rpm, and a ball-to-material ratio is 1:1 to 100:1. In an embodiment of the disclosure, the predetermined temperature is 400°C to 600°C, and time of the calcining treatment is 1h to 18h. The disclosure further provides an all-solid-state lithium-ion battery at least including a positive electrode sheet, a negative electrode sheet, and a solid electrolyte membrane. The positive electrode sheet includes a halide solid electrolyte including Li2.35Zr0.65Fe0.35Cl5Br0.5I0.5. The solid electrolyte membrane is disposed between the adjacent positive electrode sheet and negative electrode sheet. The solid electrolyte membrane includes the sulfide solid electrolyte according to the above. In an embodiment of the disclosure, the positive electrode sheet includes a positive active material selected from one or more of lithium nickel cobalt manganese oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel manganese oxide, lithium cobalt oxide, or lithium nickel cobalt aluminum oxide. The disclosure further provides an electronic apparatus including the all-solid-state lithium-ion battery according to the above. To sum up, the disclosure provides a sulfide solid electrolyte, the method of preparing the same, and the application. By introducing the E element, the O element, and the Q element into the sulfide solid electrolyte, the air stability of the sulfide solid electrolyte is effectively improved, the H2S gas generated by atmospheric degradation is reduced, and the air stability and chemical stability of the sulfide solid electrolyte are enhanced. A special dielectric layer i