SOLID ELECTROLYTE AND LITHIUM BATTERY INCLUDING THE SAME

• US 20170040637A1
• Filed: 08/02/2016
• Published: 02/09/2017
• Est. Priority Date: 08/04/2015
• Status: Active Grant

• Current Assignee: Massachusetts Institute of Technology, Samsung Electronics Co. Ltd.
• Original Assignee: Massachusetts Institute of Technology, Samsung Electronics Co. Ltd.
• Inventors: CEDER, Gerbrand, Kim, Jaechul, Miara, Lincoln, Richards, William, Tsujimura, Tomoyuki, Suzuki, Naoki, Wang, Yan
• Granted Patent: US 10,446,872 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C01B 17/22 Alkali metal sulfides or polysulfides
• CPC Class Codes: C01B 25/14 Sulfur, selenium, or tellurium compounds of phosphorus
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/0562 Solid materials
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H01M 2300/0065 Solid electrolytes
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A solid electrolyte material represented by Formula 1:

L_1+2x(M1)_1-x(M2)(M3)₄  Formula 1

• • wherein 0.25<x<1, L is at least one element selected from a Group 1 element, M1 is at least one element selected from a Group 2 element, a Group 3 element, a Group 12 element, and a Group 13 element, M2 is at least one element selected from a Group 5 element, a Group 14 element, and a Group 15 element, and M3 is at least one element selected from a Group 16 element, and wherein the solid electrolyte material has an I-4 crystal structure.

Claims

1. A solid electrolyte material represented by Formula 1:

L_1+2x(M1)₁(M2)(M3)₄ 

 

Formula 1

wherein 0.25<

x<

1,

L is at least one element selected from a Group 1 element,

M1 is at least one element selected from a Group 2 element, a Group 3 element, a Group 12 element, and a Group 13 element,

M2 is at least one element selected from a Group 5 element, a Group 14 element, and a Group 15 element, and

M3 is at least one element selected from a Group 16 element, and

wherein the solid electrolyte material has an I-4 crystal structure.

2. The solid electrolyte material of claim 1, wherein x of Formula 1 satisfies 0.625≦

x≦

0.8.

3. The solid electrolyte material of claim 1, wherein L of Formula 1 is at least one element selected from Li and Na.

4. The solid electrolyte material of claim 1, wherein the solid electrolyte material comprises greater than 1 mole of L with respect to 4 moles of M3.

5. The solid electrolyte material of claim 1, wherein M1 of Formula 1 is at least one element selected from Be, Mg, Ca, B, Al, Si, Zn, Ga, In, and Cd, and

M2 of Formula 1 is at least one element selected from P, Ge, Sn, and As.

6. The solid electrolyte material of claim 1, wherein M1 of Formula 1 is Zn and M2 of Formula 1 is P.

7. The solid electrolyte material of claim 1, wherein M3 of Formula 1 is S.

8. The solid electrolyte material of claim 1, wherein the solid electrolyte material does not comprise a disulfide bond.

9. The solid electrolyte material of claim 1, wherein the solid electrolyte material further comprises [(M2)(M3)₄]³⁻

as an anion.

10. The solid electrolyte material of claim 1, wherein the solid electrolyte material is represented by Formula 2:

Li_1+2xZn_1-xPS₄ 

 

Formula 2

wherein 0.625≦

x≦

0.8.

11. The solid electrolyte material of claim 1, wherein the solid electrolyte material has an ionic conductivity of greater than 2.9×

10<sup>−

8</sup> Siemen per centimeter as measured at room temperature.

20. A secondary battery comprising:

a positive electrode comprising a positive active material;

a negative electrode comprising a negative active material; and

a solid electrolyte layer comprising the solid electrolyte material of claim 1.

12. A method of preparing a solid electrolyte, the method comprising:

mixing a compound represented by Formula 3 and amorphous Li₃PS₄ to obtain a mixture; and

performing a heat treatment on the mixture;

L(M1)(M2)(M3)₄, 

 

Formula 3

wherein L is at least one element selected from a Group 1 element,

M1 is at least one element selected from a Group 2 element, a Group 3 element, a Group 12 element, and a Group 13 element,

M2 is at least one element selected from a Group 5 element, a Group 14 element, and a Group 15 elements, and

M3 is at least one element selected from a Group 16 element.

13. The method of claim 12, wherein the compound represented by Formula 3 is prepared by:

combining Li₂S as a L precursor, ZnS as a M1 precursor, and P₂S₅ as M2 and M3 precursors in a sealed container;

mixing the precursors Li₂S, ZnS, and P₂S₅ to obtain mixed precursors; and

performing a heat treatment on the mixed precursors at a first temperature to prepare the compound represented by Formula 3,

wherein the performing of the heat treatment on the mixture is at a second temperature and the first temperature is higher than the second temperature.

14. The method of claim 13, wherein the compound represented by Formula 3 is prepared by combining Li₂S as a L precursor, ZnS as an M1 precursor, and P₂S₅ as M2 and M3 precursors, at a molar ratio of 1:

2;

1.

15. The method of claim 12, wherein the amorphous Li₃PS₄ is prepared by mixing Li₂S and P₂S₅ at a molar ratio of 3:

1.

16. The method of claim 12, wherein the compound represented by Formula 3 and amorphous Li₃PS₄ are mixed at a molar ratio of 1:

3.

17. The method of claim 13, wherein the first temperature is in a range of about 200°

C. to about 500°

C.

18. The method of claim 13, wherein the second temperature is in a range of about 200°

C. to about 230°

C.

19. The method of claim 13, wherein the compound represented by Formula 3 has an I-4 crystal structure.