Sulfide solid electrolyte

Patent metadata

Field	Value
Publication number	US-10374253-B2
Application number	US-201916239645-A
Country	US
Kind code	B2
Filing date	Jan 4, 2019
Priority date	Sep 12, 2016
Publication date	Aug 6, 2019
Grant date	Aug 6, 2019

Abstract

A sulfide solid electrolyte that contains lithium, phosphorus, sulfur, chlorine and bromine, wherein in powder X-ray diffraction analysis using CuKα rays, it has a diffraction peak A at 2θ=25.2±0.5 deg and a diffraction peak B at 2θ=29.7±0.5 deg, the diffraction peak A and the diffraction peak B satisfy the following formula (A), and a molar ratio of the chlorine to the phosphorus “c (Cl/P)” and a molar ratio of the bromine to the phosphorus “d (Br/P)” satisfies the following formula (1):

1.2< c+d <1.9  (1)

0.845< S A /S B <1.200  (A)
where S A is an area of the diffraction peak A and S B is an area of the diffraction peak B.

First claim

The invention claimed is:

1. A sulfide solid electrolyte, comprising lithium, phosphorus, sulfur, chlorine and bromine, wherein
in powder X-ray diffraction analysis using CuKα rays, the sulfide solid electrolyte has a diffraction peak A at 2θ=25.2±0.5 deg and a diffraction peak B at 2θ=29.7±0.5 deg,
the diffraction peak A and the diffraction peak B satisfy formula (A), and
a molar ratio of the chlorine to the phosphorus, c (Cl/P), and a molar ratio of the bromine to the phosphorus, d (Br/P), satisfy formula (1):
1.2< c+d< 1.9  (1)

0.845< S A /S B <1.200  (A)

wherein S A is an area of the diffraction peak A and S B is an area of the diffraction peak B.

2. The sulfide solid electrolyte according to claim 1 , wherein the molar ratio of the bromine to the phosphorus, d (B/P), is 0.15 or more and 1.6 or less.

3. The sulfide solid electrolyte according to claim 1 , wherein the molar ratio of the chlorine to the phosphorus, c (Cl/P), and the molar ratio of the bromine to the phosphorus, d (Br/P), satisfy formula (2):
0.08< d /( c+d )<0.8  (2).

4. The sulfide solid electrolyte according to claim 1 , 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), the molar ratio of the chlorine to the phosphorus, c (Cl/P), and the molar ratio of the bromine to the phosphorus, d (Br/P), satisfy formulas (3) to (5):
5.0≤ a ≤7.5  (3)

6.5≤ a+c+d≤ 7.5  (4)

0.5≤ a−b ≤1.5  (5)

with the proviso that b>0, c>0 and d>0.

5. The sulfide solid electrolyte according to claim 1 , wherein, in powder X-ray diffraction analysis using CuKα rays, the sulfide solid electrolyte does not have a diffraction peak derived from lithium halide or, if the sulfide solid electrolyte has a diffraction peak derived from lithium halide, said diffraction peak satisfies formula (B):
0< I C /I A <0.08  (B)

wherein I C is an intensity of a diffraction peak of lithium halide, and I A is an intensity of a diffraction peak at 2θ=25.2±0.5 deg.

6. The sulfide solid electrolyte according to claim 1 , wherein, in powder X-ray diffraction analysis using CuKα rays, the sulfide solid electrolyte does not have a diffraction peak at 2θ=14.4±0.5 deg and 33.8±0.5 deg or, if the sulfide solid electrolyte has a diffraction peak at 2θ=14.4±0.5 deg and 33.8±0.5 deg, said diffraction peak satisfies formula (C):
0< I D /I A <0.09  (C)

wherein I D is an intensity of a diffraction peak at 2θ=14.4±0.5 deg and I A is an intensity of a diffraction peak at 2θ=25.2±0.5 deg.

7. The sulfide solid electrolyte according to claim 1 , wherein the sulfide solid electrolyte contains an argyrodite type crystal structure and a lattice constant of the argyrodite type crystal structure is 9.800 Å or more and 9.920 Å or less.

8. The sulfide solid electrolyte according to claim 1 , wherein:
the molar ratio of the bromine to the phosphorus, d (B/P), is 0.15 or more and 1.6 or less; and
the molar ratio of the chlorine to the phosphorus, c (Cl/P), and the molar ratio of the bromine to the phosphorus, d (Br/P), satisfy formula (2):
0.08< d /( c+d )<0.8  (2).

9. The sulfide solid electrolyte according to claim 1 , wherein:
the molar ratio of the bromine to the phosphorus, d (B/P), is 0.15 or more and 1.6 or less; and
a molar ratio of the lithium to the phosphorus, a (Li/P), a molar ratio of the sulfur to the phosphorus, b (S/P), the molar ratio of the chlorine to the phosphorus, c (Cl/P), and the molar ratio of the bromine to the phosphorus, d (Br/P), satisfy formulas (3) to (5):
5.0≤ a ≤7.5  (3)

6.5≤ a+c+d≤ 7.5  (4)

0.5≤ a−b ≤1.5  (5)

with the proviso that b>0, c>0 and d>0.

10. The sulfide solid electrolyte according to claim 1 , wherein:
the molar ratio of the chlorine to the phosphorus, c (Cl/P), and the molar ratio of the bromine to the phosphorus, d (Br/P), satisfy formula (2):
0.08< d /( c+d )<0.8  (2); and

a molar ratio of the lithium to the phosphorus, a (Li/P), a molar ratio of the sulfur to the phosphorus, b (S/P), the molar ratio of the chlorine to the phosphorus, c (Cl/P), and the molar ratio of the bromine to the phosphorus, d (Br/P), satisfy formulas (3) to (5):
5.0≤ a ≤7.5  (3)

6.5≤ a+c+d≤ 7.5  (4)

0.5≤ a−b ≤1.5  (5)

with the proviso that b>0, c>0 and d>0.

11. The sulfide solid electrolyte according to claim 1 , wherein:
the molar ratio of the bromine to the phosphorus, d (B/P), is 0.15 or more and 1.6 or less; and
in powder X-ray diffraction analysis using CuKα rays, the sulfide solid electrolyte does not have a diffraction peak derived from lithium halide or, if the sulfide solid electrolyte has a diffraction peak derived from lithium halide, said diffraction peak satisfies formula (B):
0< I C /I A <0.08  (B)

wherein I C is an intensity of a diffraction peak of lithium halide, and I A is an intensity of a diffraction peak at 2θ=25.2±0.5 deg.

12. The sulfide solid electrolyte according to claim 1 , wherein:
the molar ratio of the chlorine to the phosphorus, c (Cl/P), and the molar ratio of the bromine to the phosphorus, d (Br/P), satisfy formula (2):
0.08< d /( c+d )<0.8  (2); and

in powder X-ray diffraction analysis using CuKα rays, the sulfide solid electrolyte does not have a diffraction peak derived from lithium halide or, if the sulfide solid electrolyte has a diffraction peak derived from lithium halide, said diffraction peak satisfies formula (B):
0< I C /I A <0.08  (B)

wherein I C is an intensity of a diffraction peak of lithium halide, and I A is an intensity of a diffraction peak at 2θ=25.2±0.5 deg.

13. The sulfide solid electrolyte according to claim 1 , wherein:
the molar ratio of the bromine to the phosphorus, d (B/P), is 0.15 or more and 1.6 or less; and
in powder X-ray diffraction analysis using CuKα rays, the sulfide solid electrolyte does not have a diffraction peak at 2θ=14.4±0.5 deg and 33.8±0.5 deg or, if the sulfide solid electrolyte has a diffraction peak at 2θ=14.4±0.5 deg and 33.8±0.5 deg, said diffraction peak satisfies formula (C):
0< I D /I A <0.09  (C)

wherein I D is an intensity of a diffraction peak at 2θ=14.4±0.5 deg and I A is an intensity of a diffraction peak at 2θ=25.2±0.5 deg.

14. The sulfide solid electrolyte according to claim 1 , wherein:
the molar ratio of the chlorine to the phosphorus, c (Cl/P), and the molar ratio of the bromine to the phosphorus, d (Br/P), satisfy formula (2):
0.08< d /( c+d )<0.8  (2); and

in powder X-ray diffraction analysis using CuKα rays, the sulfide solid electrolyte does not have a diffraction peak at 2θ=14.4±0.5 deg and 33.8±0.5 deg or, if the sulfide solid electrolyte has a diffraction peak at 2θ=14.4±0.5 deg and 33.8±0.5 deg, said diffraction peak satisfies formula (C):
0< I D /I A <0.09  (C)

wherein I D is an intensity of a diffraction peak at 2θ=14.4±0.5 deg and I A is an intensity of a diffraction peak at 2θ=25.2±0.5 deg.

15. The sulfide solid electrolyte according to claim 1 , wherein:
in powder X-ray diffraction analysis using CuKα rays, the sulfide solid electrolyte does not have a diffraction peak derived from lithium halide or, if the sulfide solid electrolyte has a diffraction peak derived from lithium halide, said diffraction peak satisfies formula (B):
0< I C /I A <0.08  (B)

wherein I C is an intensity of a diffraction peak of lithium halide, and I A is an intensity of a diffraction peak at 2θ=25.2±0.5 deg; and

in powder X-ray diffraction analysis using CuKα rays, the sulfide solid electrolyte does not have a diffraction peak at

Assignees

• Idemitsu Kosan Co

Inventors

• Utsuno Futoshi
• Terai Kota
• Umeki Takashi
• Nakagawa Masaru
• Yamaguchi Hiroshi

Classifications

• C01B25/14

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

• H01M2300/0068

  inorganic · CPC title

• H01M4/62

  Selection of inactive substances as ingredients for active masses, e.g. binders, fillers · CPC title

• H01M10/0525

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

• H01B1/06

  mainly consisting of other non-metallic substances · CPC title