Sulfide solid electrolyte

Patent metadata

Field	Value
Publication number	US-2020091552-A1
Application number	US-201816610136-A
Country	US
Kind code	A1
Filing date	May 23, 2018
Priority date	May 24, 2017
Publication date	Mar 19, 2020
Grant date	—

Abstract

It is an object of the invention to provide sulfide solid electrolytes having good processability at the time of manufacturing a battery and high ionic conductivity. The present invention relates to a sulfide solid electrolyte containing lithium, phosphorus and sulfur, having a diffraction peak A at 2θ=25.2±0.5 deg and a diffraction peak B at 29.7±0.5 deg in powder X-ray diffraction using CuKα rays, and the half-value width of at least one peak obtained by separating the peaks observed in a range of 60 to 120 ppm in solid-state 31P-NMR measurements is 500 to 800 Hz.

First claim

1 . A sulfide solid electrolyte comprising lithium, phosphorus and sulfur, wherein the sulfide solid electrolyte has a diffraction peak A at 2θ=25.2±0.5 deg and a diffraction peak B at 29.7±0.5 deg in powder X-ray diffraction using CuKα rays, and
the half-value width of at least one peak obtained by separating the peaks observed in a range of 60 to 120 ppm in solid-state 31 P-NMR measurements is 500 to 800 Hz.

2 . The sulfide solid electrolyte according to claim 1 , wherein a Si-relative half-value width of the diffraction peak B is 1.3 or more and 3.0 or less.

3 . A sulfide solid electrolyte comprising lithium, phosphorus and sulfur, wherein the sulfide solid electrolyte has a diffraction peak A at 2θ=25.2±0.5 deg and a diffraction peak B at 29.7±0.5 deg in powder X-ray diffraction using CuKα rays,
a Si-relative half-value width of the diffraction peak B is 1.3 or more and 3.0 or less, and
a Si-relative peak intensity of the diffraction peak B is 0.01 or more and 0.15 or less.

4 . The sulfide solid electrolyte according to claim 1 , wherein a ratio of the area of the glass-derived peak to the total area of all peaks at 60 to 120 ppm observed in solid-state 31 P-NMR measurements is 0% or more and 10% or less.

5 . The sulfide solid electrolyte according to claim 1 , further comprising a halogen.

6 . The sulfide solid electrolyte according to claim 5 , wherein a molar ratio of the lithium to the phosphorus, a (Li/P), a molar ratio of the sulfur to the phosphorus, b (S/P), and a molar ratio of the halogen to the phosphorus, c (X/P), satisfy the following formulas (A) to (C):
5.0≤ a≤ 7.5  (A)
6.5≤ a+c≤ 7.5  (B)
0.5≤ a−b≤ 1.5  (C)
wherein in the formulas, b>0 and c>0 are satisfied.

7 . The sulfide solid electrolyte according to claim 5 , having a composition represented by the following formula (1):
Li a (P 1-α M α )S b X c   (1)
wherein in the formula, M is one or more elements selected from the group consisting of Si, Ge, Sn, Pb, B, Al, Ga, As, Sb, and Bi, and X is one or more elements selected from the group consisting of F, Cl, Br, and I; a to c satisfy the following formulas (A) to (C); and α is 0≤α≤0.3:
5.0≤ a≤ 7.5  (A)

6.5≤ a+c≤ 7.5  (B)

0.5≤ a−b≤ 1.5  (C)

wherein in the formulas, b>0 and c>0 are satisfied.

8 . The sulfide solid electrolyte according to claim 5 , comprising chlorine (Cl).

9 . The sulfide solid electrolyte according to claim 5 , comprising chlorine (Cl) and bromine (Br).

10 . An electrode mix comprising the sulfide solid electrolyte according to claim 1 and an active material.

11 . A lithium ion battery comprising the sulfide solid electrolyte according to claim 1 .

12 . An electrode mix produced from the sulfide solid electrolyte according to claim 1 .

13 . A lithium ion battery produced from the sulfide solid electrolyte according to claim 1 .

14 . A lithium ion battery comprising the electrode mix according to claim 10 .

15 . A lithium ion battery produced from the electrode mix according to claim 10 .

16 . A lithium ion battery produced from the electrode mix according to claim 12 .

Assignees

• Idemitsu Kosan Co

Inventors

• Terai Kota
• Sato Atsushi
• Utsuno Futoshi

Classifications

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• C01B25/14

  Sulfur, selenium, or tellurium compounds of phosphorus · CPC title

• C01P2002/72

  by d-values or two theta-values, e.g. as X-ray diagram · CPC title

• H01M2300/0068

  inorganic · CPC title

• C01B17/22 Primary

  Alkali metal sulfides or polysulfides · CPC title