SULFIDE SOLID ELECTROLYTE

• US 20190319305A1
• Filed: 08/08/2017
• Published: 10/17/2019
• Est. Priority Date: 11/16/2016
• Status: Active Grant

• Current Assignee: Idemitsu Kosan Company Limited
• Original Assignee: Idemitsu Kosan Company Limited
• Inventors: UTSUNO, Futoshi, NAKATA, Akiko, TERAI, Kota, NAKAGAWA, Masaru
• Granted Patent: US 11,444,317 B2
• Time in Patent Office: Days
• CPC Class Codes: C03C 3/23 containing halogen and at least one oxide, e.g. oxide of boron
• CPC Class Codes: C03C 4/14 for electro-conductive glass
• CPC Class Codes: H01B 1/06 mainly consisting of other non-metallic substances
• CPC Class Codes: H01M 10/052 Li-accumulators
• 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 2300/0068 inorganic
• CPC Class Codes: H01M 2300/008 Halides
• CPC Class Codes: H01M 4/62 Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

Provided is a sulfide solid electrolyte containing lithium, phosphorus, sulfur and chlorine, in which a molar ratio of the chlorine to the phosphorus, c (Cl/P), is greater than 1.0 and 1.9 or less, the sulfide solid electrolyte includes an argyrodite-type crystal structure, and a lattice constant of the argyrodite-type crystal structure is 9.820 Å or less.

Claims

1. :

A sulfide solid electrolyte, comprising lithium, phosphorus, sulfur and chlorine, wherein;

a molar ratio of the chlorine to the phosphorus, c (Cl/P), is greater than 1.0 and 1.9 or less,

the sulfide solid electrolyte has an argyrodite-type crystal structure, and

a lattice constant of the argyrodite-type crystal structure is 9.750 Å

or more and 9.820 Å

or less.

2. :

The sulfide solid electrolyte according to claim 1, wherein a lattice constant of the argyrodite-type crystal structure is 9.795 Å

or more and 9.820 Å

or less.

3. :

The sulfide solid electrolyte according to claim 1, wherein a lattice constant of the argyrodite-type crystal structure is 9.795 Å

or more and 9.815 Å

or less.

4. :

The sulfide solid electrolyte according to claim 1, wherein diffraction peaks are measured at 2θ

=25.5±

0.5 deg and 30.0±

0.5 deg in powder X-ray diffraction using CuKα

rays.

5. :

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), and the molar ratio of the chlorine to the phosphorus, c (Cl/P), satisfy formulas (A) to (C);

5.0≤

a≤

6.5 

 

(A)

6.1≤

a+c≤

7.5 

 

(B)

0.5≤

a−

b≤

1.5 

 

(C)

wherein b>

0 and c>

1.0 are satisfied.

6. :

The sulfide solid electrolyte according to claim 1, having a composition represented by formula (1);

Li_aPS_bCl_c 

 

(1),

wherein;

a to c satisfy formulas (A) to (C);

5.0≤

a≤

6.5 

 

(A)

6.1≤

a+c≤

7.5 

 

(B)

0.5≤

a−

b≤

1.5 

 

(C); and

b>

0 and c>

1.0 are satisfied.

7. :

The sulfide solid electrolyte according to claim 1, wherein, in powder X-ray diffraction using CuKα

rays, the sulfide solid electrolyte does not have a diffraction peak at 2θ

=50.3±

0.5 deg, or, if the sulfide solid electrolyte has a diffraction peak, said diffraction peak satisfies formula (2);

0<

I_A/I_B<

0.05 

 

(2), and

wherein I_A represents intensity of a diffraction peak at 2θ

=50.3±

0.5 deg, and In represents intensity of a diffraction peak at 2θ

=25.5±

0.5 deg.

8. :

The sulfide solid electrolyte according to claim 1, wherein, in powder X-ray diffraction using CuKα

rays, the sulfide solid electrolyte does not have a diffraction peak (not a peak arising from an argyrodite-type crystal structure) at 2θ

=17.6±

0.4 deg and 2θ

=18.1±

0.4 deg, or, if the sulfide solid electrolyte has a diffraction peak, said diffraction peak satisfies formula (3);

0<

I_C/I_D<

0.05 

 

(3), and

wherein I_C represents intensity of a diffraction peak which is not a diffraction peak arising from the argyrodite-type crystal structure between the diffraction peaks at 2θ

=17.6±

0.4 deg and 2θ

=18.1±

0.4 deg, and I_D represents intensity of a diffraction peak at 2θ

=30.0±

0.5 deg.

9. :

The sulfide solid electrolyte according to claim 1, wherein, in a solid ³¹P-NMR measurement, the sulfide solid electrolyte has a peak in each of regions 80.3 to 81.7 ppm, 82.4 to 83.7 ppm and 84.0 to 85.6 ppm; and

an area ratio of the peak in the region of 80.3 to 81.7 ppm to a total area of all peaks in the region of 78 to 92 ppm is 40% or more.

10. :

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

11. :

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

12. :

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

13. :

A lithium ion battery, comprising the electrode mix according to claim 12.