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US-20260128368-A1 - SULFIDE SOLID ELECTROLYTE, AND PREPARATION METHOD THEREOF AND USE THEREOF

US20260128368A1US 20260128368 A1US20260128368 A1US 20260128368A1US-20260128368-A1

Abstract

A sulfide solid electrolyte, and a preparation method thereof and a use thereof, where the sulfide solid electrolyte has a chemical composition of Li a Sb b P c S d O e Cl f , where 4.5≤a≤6.5, 0.02≤b≤0.9, 0.01≤e≤0.06, 0.9≤f≤1.6, b+c=1, d+e=5, and a percentage of Sb—S bonding in a total bonding formed by Sb is not less than 98%. In an X-ray diffraction pattern of the sulfide solid electrolyte, intensities of diffraction peaks at 2θ of 29.8±0.25°, 33.33±0.25° and 31.45±0.25° are I a , I b and I c , respectively; where I c /I a is 18-26%, and I c /I b is 25-36%. The sulfide solid electrolyte has good ionic conductivity, and also has good stability in air.

Inventors

  • Xia KONG
  • Huihao LI
  • Daoyan FENG
  • Jonghee Lee
  • Xufeng YAN
  • Xiaoming Wang
  • Jikang LIU
  • Chen Zhao
  • Hua Wang

Assignees

  • NINGBO RONBAY NEW ENERGY TECHNOLOGY Co.,Ltd.

Dates

Publication Date
20260507
Application Date
20251230
Priority Date
20230630

Claims (20)

  1. 1 . A sulfide solid electrolyte, having a chemical composition of Formula 1, wherein a percentage of Sb—S bonding in a total bonding formed by Sb is not less than 98%, in Formula 1, 4.5≤a≤6.5, 0.02≤b≤0.9, 0.01≤e≤0.06, 0.9≤f≤1.6, b+c=1, d+e=5; in an X-ray diffraction pattern of the sulfide solid electrolyte, intensities of diffraction peaks at 2θ of 29.8±0.25°, 33.33±0.25° and 31.45±0.25° are I a , I b and I c , respectively, wherein I c /I a is 18-26%, and I c /I b is 25-36%.
  2. 2 . The sulfide solid electrolyte according to claim 1 , wherein a room-temperature ionic conductivity of the sulfide solid electrolyte is not less than 7.5 mS/cm.
  3. 3 . The sulfide solid electrolyte according to claim 1 , wherein an ionic conductivity retention rate of the sulfide solid electrolyte is not less than 70%.
  4. 4 . The sulfide solid electrolyte according to claim 1 , wherein the sulfide solid electrolyte is prepared by a method comprising the following processes: mixing Sb 2 S 5 , a P source and an O source and performing a primary milling, adding a Li source and a Cl source and performing a secondary milling, to obtain an intermediate phase, sintering the intermediate phase, to obtain the sulfide solid electrolyte.
  5. 5 . The sulfide solid electrolyte according to claim 2 , wherein the sulfide solid electrolyte is prepared by a method comprising the following processes: mixing Sb 2 S 5 , a P source and an O source and performing a primary milling, adding a Li source and a Cl source and performing a secondary milling, to obtain an intermediate phase, sintering the intermediate phase, to obtain the sulfide solid electrolyte.
  6. 6 . The sulfide solid electrolyte according to claim 3 , wherein the sulfide solid electrolyte is prepared by a method comprising the following processes: mixing Sb 2 S 5 , a P source and an O source and performing a primary milling, adding a Li source and a Cl source and performing a secondary milling, to obtain an intermediate phase, sintering the intermediate phase, to obtain the sulfide solid electrolyte.
  7. 7 . A preparation method of the sulfide solid electrolyte according to claim 1 , comprising the following steps: (1) mixing Sb 2 S 5 , a P source and an O source and performing a primary milling, then adding a Li source and a Cl source and performing a secondary milling, to obtain an intermediate phase; and (2) performing a sintering treatment on the intermediate phase, to obtain the sulfide solid electrolyte.
  8. 8 . The preparation method of the sulfide solid electrolyte according to claim 7 , wherein a room-temperature ionic conductivity of the sulfide solid electrolyte is not less than 7.5 mS/cm.
  9. 9 . The preparation method of the sulfide solid electrolyte according to claim 7 , wherein an ionic conductivity retention rate of the sulfide solid electrolyte is not less than 70%.
  10. 10 . The preparation method of the sulfide solid electrolyte according to claim 7 , wherein in step (1), the P source comprises at least one of P 2 O 5 and P 2 S 5 ; the O source comprises at least one of P 2 O 5 and Li 2 O; the Li source comprises at least one of Li 2 O, Li 2 S and LiCl; the Cl source comprises LiCl.
  11. 11 . The preparation method of the sulfide solid electrolyte according to claim 8 , wherein in step (1), the P source comprises at least one of P 2 O 5 and P 2 S 5 ; the O source comprises at least one of P 2 O 5 and Li 2 O; the Li source comprises at least one of Li 2 O, Li 2 S and LiCl; the Cl source comprises LiCl.
  12. 12 . The preparation method of the sulfide solid electrolyte according to claim 9 , wherein in step (1), the P source comprises at least one of P 2 O 5 and P 2 S 5 ; the O source comprises at least one of P 2 O 5 and Li 2 O; the Li source comprises at least one of Li 2 O, Li 2 S and LiCl; the Cl source comprises LiCl.
  13. 13 . The preparation method of the sulfide solid electrolyte according to claim 7 , wherein in step (1), a rotation speed of the primary milling is 350-550 r/min, and a time for the primary milling is 0.5-2 h.
  14. 14 . The preparation method of the sulfide solid electrolyte according to claim 8 , wherein in step (1), a rotation speed of the primary milling is 350-550 r/min, and a time for the primary milling is 0.5-2 h.
  15. 15 . The preparation method of the sulfide solid electrolyte according to claim 9 , wherein in step (1), a rotation speed of the primary milling is 350-550 r/min, and a time for the primary milling is 0.5-2 h.
  16. 16 . The preparation method of the sulfide solid electrolyte according to claim 7 , wherein in step (1), a rotation speed of the secondary milling is 350-550 r/min, and a time for the secondary milling is 3-5 h.
  17. 17 . The preparation method of the sulfide solid electrolyte according to claim 8 , wherein in step (1), a rotation speed of the secondary milling is 350-550 r/min, and a time for the secondary milling is 3-5 h.
  18. 18 . The preparation method of the sulfide solid electrolyte according to claim 9 , wherein in step (1), a rotation speed of the secondary milling is 350-550 r/min, and a time for the secondary milling is 3-5 h.
  19. 19 . The preparation method of the sulfide solid electrolyte according to claim 7 , wherein a temperature of the sintering treatment is 530-580° C., and a time for the sintering treatment is 4-6 h.
  20. 20 . An all-solid-state lithium-ion battery, comprising the sulfide solid electrolyte according to claim 1 .

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application is a continuation of International Application No. PCT/CN2024/102140, filed on Jun. 27, 2024, which claims priority to Chinese Patent Application No. 202310798194.3 filed with China National Intellectual Property Administration on Jun. 30, 2023. Both of the aforementioned applications are incorporated by reference in their entireties. TECHNICAL FIELD The present application relates to the field of lithium-ion batteries, and particularly relates to a sulfide solid electrolyte and a preparation method thereof and a use thereof. BACKGROUND Lithium-ion batteries have been widely used in various portable electronic products, new energy vehicles and other fields due to their advantages such as high energy density, high operating voltage, and long service life. However, the liquid electrolytes used in traditional lithium-ion batteries are highly unstable and prone to combustion and explosion under high temperatures, short circuits, or physical impacts, posing significant safety risks. In contrast, solid electrolytes used in solid-state lithium-ion batteries can fundamentally resolve the safety issues of liquid lithium-ion batteries and can also operate under extreme conditions such as high or low temperatures. Currently, the more extensively studied solid electrolytes mainly include oxide solid electrolytes and sulfide solid electrolytes. Among them, oxide solid electrolytes exhibit high oxidation potential and good stability, but generally suffer from low ionic conductivity, high rigidity, and poor ductility. Sulfide solid electrolytes have higher ionic conductivity and good mechanical properties because the sulfur ions have weaker binding to cations due to smaller electronegativity and facilitate lithium-ion transport due to larger radius. However, sulfide solid electrolytes are unstable in air and readily undergo irreversible side reactions with moisture, oxygen, and carbon dioxide in the air, releasing toxic hydrogen sulfide gas, which causes a collapsed structure of the sulfide solid electrolyte, a decreased ionic conductivity, and affects the long-term cycling performance of the battery, and thus seriously restricts the application of sulfide solid electrolytes in all-solid-state lithium batteries. Therefore, it is necessary to develop a sulfide solid electrolyte with good air stability. SUMMARY In view of the above-described defects in the prior art, the present application provides a sulfide solid electrolyte having good ionic conductivity and having good stability in air. The present application provides a preparation method of a sulfide solid electrolyte, which method is simple, has low operation cost, and can promote the formation of Sb—S bonding and P—O bonding, improving the air stability and ionic conductivity of the electrolyte. The present application further provides an all-solid-state lithium-ion battery, including the sulfide solid electrolyte described above. The all-solid-state lithium-ion battery has good cycling performance and rate capability. The present application provides a sulfide solid electrolyte, having a chemical composition of Formula 1, where a percentage of Sb—S bonding in a total bonding formed by Sb is not less than 98%, in Formula 1, 4.5≤a≤6.5, 0.02≤b≤0.9, 0.01≤e≤0.06, 0.9≤f≤1.6, b+c=1, d+e=5;in an X-ray diffraction pattern of the sulfide solid electrolyte, intensities of diffraction peaks at 2θ of 29.8±0.25°, 33.33±0.25° and 31.45±0.25° are Ia, Ib and Ic, respectively, where Ic/Ia is 18-26%, and Ic/Ib is 25-36%. Further, a room-temperature ionic conductivity of the sulfide solid electrolyte is not less than 7.5 mS/cm. Further, an ionic conductivity retention rate of the sulfide solid electrolyte is not less than 70%. Further, the sulfide solid electrolyte is prepared by a method including the following process: mixing Sb2S5, a P source and an O source and performing a primary milling, then adding a Li source and a Cl source and performing a secondary milling, to obtain an intermediate phase, sintering the intermediate phase, to obtain the sulfide solid electrolyte. The present application further provides a preparation method of a sulfide solid electrolyte, including the following steps: (1) mixing Sb2S5, a P source and an O source and performing a primary milling, then adding a Li source and a Cl source and performing a secondary milling, to obtain an intermediate phase; and(2) performing a sintering treatment on the intermediate phase, to obtain the sulfide solid electrolyte. Further, in step (1), the P source includes at least one of P2O5 and P2S5; the O source includes at least one of P2O5 and Li2O; the Li source includes at least one of Li2O, Li2S and LiCl; the Cl source includes LiCl. Further, in step (1), a rotation speed of the primary milling is 350-550 r/min, and a time for the primary milling is 0.5-2 h. Further, in step (1), a rotation speed of the secondary milling is 350-550 r/min, and a time for the seco