All-solid-state secondary battery and manufacturing method therefor

Patent metadata

Field	Value
Publication number	US-12512508-B2
Application number	US-202118013079-A
Country	US
Kind code	B2
Filing date	Jul 13, 2021
Priority date	Oct 12, 2020
Publication date	Dec 30, 2025
Grant date	Dec 30, 2025

Abstract

Provided are an all-solid secondary battery and a method of manufacturing the same, the all-solid secondary battery including: an anode layer; a cathode layer; and a solid electrolyte layer between the anode layer and the cathode layer, wherein the cathode layer contains a large-particle cathode active material, a small-diameter cathode active material, and a solid electrolyte, the solid electrolyte layer includes a first solid electrolyte layer adjacent to the cathode layer and containing a first solid electrolyte, and a second solid electrolyte layer adjacent to the anode layer and containing a second electrolyte, the second solid electrolyte has a larger size than the solid electrolyte of the cathode layer or the first solid electrolyte, and the second solid electrolyte has higher ion conductivity than the first solid electrolyte.

First claim

The invention claimed is:

1 . An all-solid secondary battery, comprising:
an anode layer; a cathode layer; and a solid electrolyte layer between the anode layer and the cathode layer, wherein: the cathode layer contains a large-particle cathode active material, a small-particle cathode active material, and a solid electrolyte, the solid electrolyte layer includes a first solid electrolyte layer adjacent to the cathode layer and containing a first solid electrolyte, and a second solid electrolyte layer adjacent to the anode layer and containing a second solid electrolyte, the second solid electrolyte has a larger size than the solid electrolyte of the cathode layer or the first solid electrolyte, and the second solid electrolyte has higher ion conductivity than the first solid electrolyte.

2 . The all-solid secondary battery of claim 1 , wherein, in the cathode layer,
the large-particle cathode active material has a size of 14 μm or more, and the small-particle cathode active material has a size of 6 μm or less.

3 . The all-solid secondary battery of claim 1 , wherein, in the cathode layer,
the large-particle cathode active material has a size of 14 μm to 20 μm, and the small-particle cathode active material has a size of 3 μm to 5.5 μm.

4 . The all-solid secondary battery of claim 1 , wherein each of the solid electrolyte and the first solid electrolyte has a size of 3 μm or less.

5 . The all-solid secondary battery of claim 4 , wherein the solid electrolyte is a solid electrolyte having a size of 3 μm or less, and
the solid electrolyte is a solid electrolyte having a size of 1 μm to 3 μm, a solid electrolyte having a size of 1 μm or less, or a combination thereof.

6 . The all-solid secondary battery of claim 5 , wherein at least 80% by weight of the solid electrolyte is a solid electrolyte having a size of 1 μm or less.

7 . The all-solid secondary battery of claim 1 , wherein the second solid electrolyte is a solid electrolyte having a size of 3 μm to 10 μm, a solid electrolyte having a size of 1 μm to 3 μm, or a combination thereof.

8 . The all-solid secondary battery of claim 1 , wherein a solid electrolyte having a size of 1.0 μm or less or the first solid electrolyte is included in an interface between the cathode layer and the first solid electrolyte layer.

9 . The all-solid secondary battery of claim 1 , further comprising: a third solid electrolyte layer including a third solid electrolyte between the second solid electrolyte layer and the anode layer.

10 . The all-solid secondary battery of claim 9 , wherein the third solid electrolyte is a third solid electrolyte having a size of 3 μm or less, and
the third solid electrolyte is a solid electrolyte having a size of having a size of about 1 μm to about 3 μm, a solid electrolyte having a size of 1 μm or less, or a combination thereof.

11 . The all-solid secondary battery of claim 9 , wherein the third solid electrolyte having a size of 1.0 μm or less is included in an interface between the anode layer and the third solid electrolyte layer.

12 . The all-solid secondary battery of claim 1 , wherein
a ratio (Z 1 /Z 2 ) of a size Z 1 of the solid electrolyte of the cathode layer and a size Z 2 of the first solid electrolyte of the first solid electrolyte layer is about 0.33 to about 3.0.

13 . The all-solid secondary battery of claim 1 , wherein the solid electrolyte or the first solid electrolyte contains a compound having an argyrodite crystal structure and including chlorine (Cl), and
the second solid electrolyte contains a compound having an argyrodite crystal structure and including i) a halogen selected from Br, I, and a combination thereof, and ii) chlorine (Cl).

14 . The all-solid secondary battery of claim 1 , wherein the solid electrolyte or the first solid electrolyte includes a compound represented by Formula 1 and having an argyrodite crystal structure:
Li a M x PS b (Cl) d   <Formula 1>
in Formula 1, M is Na, K, Fe, Mg, Ca, Ag, Cu, Zr, Zn, or a combination thereof, X is Br, I, or a combination thereof, and 0≤x≤0.07, a is a number from 5 to 6, b is a number from 4 to 6, 0<d≤2, and 5≤a+x≤6.

15 . The all-solid secondary battery of claim 1 , wherein the second solid electrolyte includes a compound represented by Formula 2 and having an argyrodite crystal structure:
Li a M x PS b (X1) c1 (Cl) d1   <Formula 2>
in Formula 2, M is Na, K, Fe, Mg, Ca, Ag, Cu, Zr, Zn, or a combination thereof, X1 is Br, I, or a combination thereof, and 0≤x≤0.07, a is a number from 5 to 6, b is a number from 4 to 6, c1>0, d1>0, 0<c1+d1≤2, and 5≤a+x≤6.

16 . The all-solid secondary battery of claim 15 , wherein 1.5≤c1+d1≤2.

17 . The all-solid secondary battery of claim 1 , further comprising: a third solid electrolyte layer including a third solid electrolyte between the second solid electrolyte layer and the anode layer, wherein the third solid electrolyte includes a compound represented by Formula 1 and having an argyrodite crystal structure:
Li a M x PS b (Cl) d   <Formula 1>
in Formula 1, M is Na, K, Fe, Mg, Ca, Ag, Cu, Zr, Zn, or a combination thereof, X is Br, I, or a combination thereof, and 0≤x≤0.07, a is a number from 5 to 6, b is a number from 4 to 6, 0<d≤2, and 5≤a+x≤6.

18 . The all-solid secondary battery of claim 1 , wherein the first solid electrolyte has an ion conductivity of about 1 mS/cm to about 5 mS/cm at 25° C., and
the second solid electrolyte has an ion conductivity of about 3 mS/cm to about 7 mS/cm at 25° C.

19 . The all-solid secondary battery of claim 1 , wherein a thickness ratio of the first solid electrolyte layer and the second solid electrolyte layer is about 1:1 to about 1:10.

20 . The all-solid secondary battery of claim 1 , wherein the first solid electrolyte has a thickness of about 1 μm to about 35 μm, the second solid electrolyte has a thickness of about 10 μm to about 60 μm, a third solid electrolyte layer is further provided between the second solid electrolyte layer and the anode layer, and the third solid electrolyte layer has a thickness of about 1 μm to about 35 μm.

21 . The all-solid secondary battery of claim 15 , wherein the compound represented by Formula 2 is a compound represented by Formula 3:
(Li 1-x1 M x1 ) 7-y PS 6-y (Br 1-x2 (Cl) x2 ) y   <Formula 3>
in Formula 3, M is Na, K, Fe, Mg, Ca, Ag, Cu, Zr, Zn, or a combination thereof, and
0≤ x 1<1,0< x 2<1, and 0≤ y≤ 2.

22 . The all-solid secondary battery of claim 15 , wherein the compound represented by Formula 2 is a compound represented by Formula 4:
Li a M x PS b (Br) c (Cl) d   <Formula 4>
in Formula 4, M is Na, K, Fe, Mg, Ca, Ag, Cu, Zr, Zn, or a combination thereof, X is Br, I, or a combination thereof, and 0≤x≤0.07, a is a number from 5 to 6, b is a number from 4 to 6, c>0, d>0, 0<c+d≤2, and 5≤a+x≤6.

23 . The all-solid secondary battery of claim 14 , wherein the compound represented by Formula 1 is Li 5.75 PS 4.75 Cl 1.25 , Li 5.75 PS 4.5 Cl 1.5 , Li 5.5 PS 4.5 Cl 1.5 , Li 5.45 Na 0.05 PS 4.5 Cl 1.5 , Li 5.45 K 0.05 PS 4.5 Cl 1.5 , Li 5.74 PS 4.74 Cl 1.26 , LisNa 0.05 PS 4 Cl 2 , Li 5 K 0.05 PS 4 Cl 2 , Li 5.8 PS 4.8 Cl 1.2 , Li 5.7 Na 0.05 PS 4.75 Cl 1.25 , Li 5.7 Cu 0.05 PS 4.75 Cl 1.25 , Li 5.65 Cu 0.1 PS 4.75 Cl 1.25 , or a combination thereof.

24 . The all-solid secondary battery of claim 15 , wherein the compound represented by Formula 2 is Li 5.5 PS 4.5 Cl 0.75

Assignees

• Samsung Sdi Co Ltd

Inventors

• Ku Junhwan
• Lee Seoksoo
• Park Youngsin
• Sugimoto Toshinori

Classifications

• H01M2300/0094

  in the form of layered products, e.g. coatings · CPC title

• H01M2300/008

  Halides · CPC title

• H01M2300/0068

  inorganic · CPC title

• H01M4/405

  Alloys based on lithium · CPC title

• H01M4/382

  Lithium (H01M4/405 takes precedence) · CPC title