Method of preparing solid electrolyte and all-solid battery including solid electrolyte prepared by the method

Patent metadata

Field	Value
Publication number	US-11799126-B2
Application number	US-202016886897-A
Country	US
Kind code	B2
Filing date	May 29, 2020
Priority date	May 31, 2019
Publication date	Oct 24, 2023
Grant date	Oct 24, 2023

Abstract

A method of preparing a solid electrolyte and an all-solid battery including a solid electrolyte prepared by the method, the method including: contacting a first solvent and a first starting material comprising an alkali metal, sulfur, phosphorus, an element M, or a combination thereof to form a first solution; precipitating a first precursor from the first solution; contacting a second solvent, the first precursor, and a second starting material comprising an alkali metal, sulfur, phosphorus, an element M, or a combination thereof to form a second solution; precipitating a second precursor from the second solution; and heat treating the second precursor to prepare the solid electrolyte, wherein the element M comprises an element of Group 14 of the Periodic Table of the Elements, and the element M and the alkali metal in the first starting material and the second starting material are the same or different.

First claim

What is claimed is:

1. A method of preparing a solid electrolyte, the method comprising:
contacting a first solvent and a first starting material comprising an alkali metal, sulfur, phosphorus, an element M, or a combination thereof to form a first solution;
precipitating a first precursor from the first solution;
contacting a second solvent, the first precursor, and a second starting material comprising an alkali metal, sulfur, phosphorus, an element M, or a combination thereof to form a second solution;
wherein the element M comprises an element of Group 14 of the Periodic Table of the Elements,
wherein when the element M is present in the first starting material and the element M is present in second starting material, the element M in the first starting material and
the element M in second starting material are the same or different, and wherein the alkali metal in the first starting material and the alkali metal in second starting material are the same or different;

precipitating a second precursor from the second solution, and
heat treating the second precursor to prepare the solid electrolyte,
wherein the first solvent comprises methanol, ethanol, propanol, isopropanol, butanol, acetone, methyl ethyl ketone, butyl acetate, chloroform, acetonitrile, 1,2-dichloroethane, nitroethane, oleic acid, nitrobenzene, benzonitrile, dimethyl sulfoxide, dimethyl acetamide, N-methylformamide, or a combination thereof, and
wherein the first solvent and the second solvent are different from each other.

2. The method of claim 1 , wherein the element M is insoluble in the first solvent or the second solvent.

3. The method of claim 1 , wherein the element M is silicon, germanium, or a combination thereof.

4. The method of claim 1 , wherein a Gutmann Donor Number of the second solvent is 20 or less.

5. The method of claim 4 , wherein the second solvent comprises nitromethane, carbon tetrachloride, chlorobenzene, cyclohexane, hexane, o-xylene, tetrahydrofuran, benzonitrile, 1,4-dioxane, acetonitrile, nitrobenzene, or a combination thereof.

6. The method of claim 1 , wherein the heat treating of the second precursor is at a temperature in a range of 500° C. to 600° C.

7. The method of claim 6 , wherein the heat treating is performed in a vacuum.

8. The method of claim 1 , wherein the first precursor and the second starting material are soluble in the second solvent.

9. The method of claim 1 , wherein the precipitating of the first precursor comprises
adding the first starting material to the first solvent under an inert atmosphere, and
dissolving the first starting material in the first solvent under the inert atmosphere, and then
stirring for 10 hours or more.

10. The method of claim 1 , wherein the precipitating of the second precursor comprises
adding the first precursor and the second starting material to the second solvent under an inert atmosphere, and
dissolving the first precursor and the second starting material in the second solvent under the inert atmosphere, and then
stirring for 5 days or more.

11. The method of claim 1 , wherein the first starting material comprises lithium, sulfur, and germanium, and
wherein the first solvent does not dissolve the germanium.

12. An all-solid battery comprising:
a cathode;
an anode; and
a solid electrolyte layer disposed between the cathode and the anode,
wherein the solid electrolyte layer includes a solid electrolyte prepared by the method of claim 1 .

13. The all-solid battery of claim 12 , wherein the solid electrolyte is represented by Formula 1:
A 10+x M 1+x P 2-x S 12   Formula 1

wherein, in Formula 1, A comprises an element of Group 1 of the Periodic Table of the Elements,
M comprises an element of Group 14 of the Periodic Table of the Elements, and
0≤x<1.

14. The all-solid battery of claim 13 , wherein A is lithium, sodium, potassium, or a combination thereof.

15. The all-solid battery of claim 13 , wherein M comprises silicon, germanium, tin, or a combination thereof.

16. The all-solid battery of claim 13 , wherein 0≤x≤0.5.

17. The all-solid battery of claim 12 , wherein the solid electrolyte has a peak at positions 12.3±0.5° 2θ, 14.3±0.5° 2θ, 17.3±0.5° 2θ, 20.1±0.5° 2θ, 20.4±0.5° 2θ, 23.9±0.5° 2θ, 26.8±0.5° 2θ, 29.4±0.5° 2θ, 36.6±0.5° 2θ, 37.6±0.5° 2θ, 40.9±0.5° 2θ, 41.4±0.5° 2θ, 42.2±0.5° 2θ, 47.3±0.5° 2θ, 51.6±0.5° 2θ, and 52.6±0.5° 2 θ, when analyzed by X-ray diffraction using Cu Kα radiation.

18. The method of claim 1 , wherein the element M comprises germanium and the first solvent or the second solvent comprises ethanol.

19. A method of preparing a solid electrolyte, the method comprising:
contacting
a first solvent and
a first starting material comprising
a germanium-containing compound and
Li 2 S

to form a first solution;
precipitating a first precursor comprising germanium from the first solution;
contacting
a second solvent,
the first precursor comprising germanium, and
a second starting material comprising
Li 2 S and
P 2 S 5 to form a second solution;

precipitating a second precursor from the second solution; and
heat treating the second precursor to prepare the solid electrolyte,
wherein the solid electrolyte is represented by Formula 1:
Li 10+x Ge 1+x P 2-x S 12   Formula 1

wherein 0≤x<1,
wherein the first solvent comprises methanol, ethanol, propanol, isopropanol, butanol, acetone, methyl ethyl ketone, butyl acetate, chloroform, acetonitrile, 1,2-dichloroethane, nitroethane, oleic acid, nitrobenzene, benzonitrile, dimethyl sulfoxide, dimethyl acetamide, N-methylformamide, or a combination thereof, and
wherein the first solvent and the second solvent are different from each other.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Tsujimura Tomoyuki
• Aihara Yuichi
• Machida Nobuya

Classifications

• H01M10/0562 Primary

  Solid materials · CPC title

• C01B17/22

  Alkali metal sulfides or polysulfides · CPC title

• H01M4/0471

  involving thermal treatment, e.g. firing, sintering, backing particulate active material, thermal decomposition, pyrolysis · CPC title

• H01M4/382

  Lithium (H01M4/405 takes precedence) · CPC title

• H01M4/386

  Silicon or alloys based on silicon · CPC title