Solid electrolyte material and all solid secondary battery including same

Patent metadata

Field	Value
Publication number	US-2020161699-A1
Application number	US-201916683457-A
Country	US
Kind code	A1
Filing date	Nov 14, 2019
Priority date	Nov 16, 2018
Publication date	May 21, 2020
Grant date	—

Abstract

An all-solid secondary battery includes: a cathode layer including a cathode active material; an anode layer; and a solid electrolyte layer disposed between the cathode layer and the anode layer, wherein at least one of the cathode layer, the anode layer, or the solid electrolyte layer includes a phase-transition solid electrolyte material, wherein upon heating, the phase-transition solid electrolyte material undergoes a phase transition from a first phase to a second phase, and the second phase has an ionic conductivity less than the ionic conductivity of the first phase.

First claim

What is claimed is:

1 . A phase-transition solid electrolyte material comprising: at least one sulfide represented by Formula (4) or Formula (5)
d ( e LiBr-(1- e )LiCl)-(1- d )Li 3 PS 4   (4)
d ( e LiBr-(1- e )LiCl)-2(1- d )(0.75Li 2 S-0.25P 2 S 5 )  (5)
wherein, in Formula (4) and Formula (5), d and e are each independently 0.1≤d≤0.7, and 0≤e≤1.

2 . An all-solid secondary battery comprising:
a cathode layer comprising a cathode active material; an anode layer; and a solid electrolyte layer between the cathode layer and the anode layer, wherein at least one of the cathode layer, the anode layer, or the solid electrolyte layer comprises a phase-transition solid electrolyte material, wherein upon heating, the phase-transition solid electrolyte material undergoes a phase transition from a first phase to a second phase, and the second phase has an ionic conductivity that is less than an ionic conductivity of the first phase.

3 . The all-solid secondary battery of claim 2 , wherein
the phase-transition of the phase-transition solid electrolyte material occurs at a temperature equal to or less than a decomposition temperature of the cathode active material.

4 . The all-solid secondary battery of claim 2 , wherein
the phase-transition of the phase-transition solid electrolyte material occurs in a temperature range of about 200° C. or greater to about 300° C. or less.

5 . The all-solid secondary battery of claim 2 , wherein
the phase-transition solid electrolyte material comprises Li 2 S and P 2 S 5 .

6 . The all-solid secondary battery of claim 2 , wherein
the phase-transition solid electrolyte material comprises at least one sulfide material represented by Formula (6):
a Li 2 S-(1- a )P 2 S 6   (6)

wherein, in Formula (6), 0.7<a<0.9.

7 . The all-solid secondary battery of claim 6 , wherein,
in Formula (6), 0.72<a<0.8.

8 . The all-solid secondary battery of claim 2 , wherein
the phase-transition solid electrolyte material comprises at least one sulfide material represented by Formula (1):
b LiX-(1- b )(cLi 2 S-(1- c )P 2 S 5 )  (1)

wherein, in Formula (1),
0.01≤b≤0.7,
0.6≤c≤0.9,
and X is at least one of Cl, Br, or I.

9 . The all-solid secondary battery of claim 8 , wherein,
in Formula (1),
0.2≤b≤0.67, and
0.7≤c≤0.8.

10 . The all-solid secondary battery of claim 1 , wherein
the phase-transition solid electrolyte material comprises at least one sulfide represented by Formula (2) or Formula (3):
d ( e LiBr-(1- e )LiCl)-(1- d )Li 3 PS 4   (2)

d ( e LiBr-(1- e )LiCl)-2(1- d )(0.75Li 2 S-0.25P 2 S 5 )  (3)

wherein, in Formula (2) and Formula (3), d and e are each independently 0.1≤d≤0.7, and 0≤e≤1.

11 . The all-solid secondary battery of claim 2 , wherein
the cathode active material comprises
a layered oxide material comprising Li and at least one of Ni, Co, Mn, or Al; and
at least one of elemental sulfur or a sulfur compound.

12 . The all-solid secondary battery of claim 1 , wherein
the cathode active material comprises a compound represented by LiNi x Co y Al z O 2 or LiNi x Co y Mn z .O 2 , wherein 0<x<1, 0<y<1, 0<z<1, x+y+z=1, 0<x′<1, 0<y′<1, 0<z′<1, and x′+y′+z′=1.

13 . The all-solid secondary battery of claim 2 , wherein
the anode layer comprises an anode active material, and the anode active material comprises a material which forms an alloy or a compound with lithium.

14 . The all-solid secondary battery of claim 13 , wherein
the anode active material is lithium metal.

15 . The all-solid secondary battery of claim 2 , wherein,
a charge capacity ratio between the cathode layer and the anode layer satisfies the relationship represented by Formula (I):
0.002< b/a< 0.5  (I)

wherein, in Formula (I), a is a charge capacity of the cathode layer, and b is a charge capacity of the anode layer.

16 . The all-solid secondary battery of claim 2 , wherein
the solid electrolyte layer comprises a first solid electrolyte layer and a second solid electrolyte layer, the first solid electrolyte layer comprises the phase-transition solid electrolyte material, and the second solid electrolyte layer comprises a solid electrolyte material which is different from the phase-transition solid electrolyte material.

17 . The all-solid secondary battery of claim 16 , wherein
the solid electrolyte material which is different from the phase-transition solid electrolyte material comprises a sulfide-containing solid electrolyte material.

18 . The all-solid secondary battery of claim 16 , wherein
the first solid electrolyte layer is in contact with the cathode layer.

19 . The all-solid secondary battery of claim 16 , wherein
the first solid electrolyte layer is in contact with the anode layer.

20 . The all-solid secondary battery of claim 16 , wherein
the first solid electrolyte layer is in contact with the second solid electrolyte layer.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Ito Seitaro
• Tsujimura Tomoyuki
• Aihara Yuichi

Classifications

• H01M10/0585

  of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators · CPC title

• C01P2006/40

  Electric properties · CPC title

• H01M4/525

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title

• C01G53/42

  containing alkali metals, e.g. LiNiO2 · CPC title

• H01M4/382

  Lithium (H01M4/405 takes precedence) · CPC title