Solid state electrolyte layer, electrode active material layer, all solid state lithium battery, manufacturing method for solid state electrolyte layer, and manufacturing method for electrode active material layer
A solid state electrolyte layer includes a sulfide solid state electrolyte material that is manufactured from a raw material composition containing Li 2 S and P 2 S 5 and is substantially free of bridging sulfur, and a hydrophobic polymer for binding the sulfide solid state electrolyte material.
1. A solid state electrolyte layer comprising:
a sulfide solid state electrolyte material that is manufactured from a raw material composition containing Li 2 S and P 2 S 5 and includes no more than 10 mol % of a bridging sulfur of an S 3 P—S—PS 3 unit; and
a hydrophobic polymer for binding the sulfide solid state electrolyte material.
2. The solid state electrolyte layer according to claim 1 , wherein the hydrophobic polymer is a hydrocarbon-based polymer.
3. The solid state electrolyte layer according to claim 2 , wherein the hydrocarbon-based polymer is a styrene-butadiene rubber or a styrene-ethylene-butadiene rubber.
4. The solid state electrolyte layer according to claim 1 , wherein a ratio of a mole number of the P 2 S 5 to a mole number of the Li 2 S in the raw material composition is no smaller than 11/39 and no larger than 14/36.
5. The solid state electrolyte layer according to claim 1 , wherein the sulfide solid state electrolyte material is a sulfide glass.
6. The solid state electrolyte layer according to claim 1 , wherein the sulfide solid state electrolyte material is a crystallized sulfide glass.
7. An all solid state lithium battery comprising:
a positive electrode active material layer;
a negative electrode active material layer; and
the solid state electrolyte layer according to claim 1 , which is formed between the positive electrode active material layer and the negative electrode active material layer.
8. A method for manufacturing a solid state electrolyte layer, comprising:
mixing a sulfide solid state electrolyte material that is manufactured by amorphizing a raw material composition containing Li 2 S and P 2 S 5 and includes no more than 10 mol % of a bridging sulfur of an S 3 P—S—PS 3 unit with a hydrophobic polymer in a solvent to prepare a solid state electrolyte layer forming slurry; and
coating a substrate with the solid state electrolyte layer forming slurry to form a solid state electrolyte layer forming coated film,
wherein a ratio of mole number of the P 2 S 5 to a mole number of the Li 2 S in the raw material composition is no smaller than 11/39 and no larger than 14/36, and
mechanical milling is performed with a zirconia pot and zirconia balls to obtain the sulfide solid state electrolyte material.
9. The solid state electrolyte layer according to claim 1 , wherein a ratio of a mole number of the P 2 S 5 to a mole number of the Li 2 S in the raw material composition is from 75:25 to 78:22.
10. The solid state electrolyte layer according to claim 1 , wherein
the hydrophobic polymer is free of a hydrophilic group, and the hydrophobic polymer is at least one selected from the group consisting of styrene-ethylene-butadiene, butyl rubber, isoprene rubber, ethylene-propylene-diene rubber, olefin-based and non-diene-based elastomer, and fluorine-based and non-diene-based elastomer.
11. The solid state electrolyte layer according to claim 10 , wherein
a content of the hydrophobic polymer in the solid state electrolyte layer is from 0.01% to 30% by weight.
12. The solid state electrolyte layer according to claim 1 , wherein
the solid state electrolyte layer does not include unreacted Li 2 S.
13. The solid state electrolyte layer according to claim 1 , wherein
a content of the sulfide solid state electrolyte material in the electrode active material layer is 90% by weight or more.
14. The solid state electrolyte layer according to claim 13 , wherein
the content of the sulfide solid state electrolyte material content in the electrode active material layer is 95% by weight or more.
15. The solid state electrolyte layer according to claim 1 , wherein
a number average molecular weight of the hydrophobic polymer is from 1,000 to 700,000.
16. The solid state electrolyte layer according to claim 15 , wherein
the number average molecular weight of the hydrophobic polymer is from 10,000 to 100,000.
17. The solid state electrolyte layer according to claim 16 , wherein
the number average molecular weight of the hydrophobic polymer is from 30,000 to 80,000.
18. The solid state electrolyte layer according to claim 1 , wherein
a content of the hydrophobic polymer in the solid state electrolyte layer is from 0.01% to 30% by weight.
19. The solid state electrolyte layer according to claim 18 , wherein
the content of the hydrophobic polymer in the solid state electrolyte layer is from 0.1% to 10% by weight.
20. The solid state electrolyte layer according to claim 1 , wherein
a thickness of the solid state electrolyte layer is from 0.1 μm to 1000 μm.
21. The solid state electrolyte layer according to claim 20 , wherein
the thickness of the solid state electrolyte layer is from 0.1 μm to 300 μm.
22. The method according to claim 8 , wherein
the hydrophobic polymer is free of a hydrophilic group, and the hydrophobic polymer is at least one selected from the group consisting of styrene-ethylene-butadiene, butyl rubber, isoprene rubber, ethylene-propylene-diene rubber, olefin-based and non-diene-based elastomer, and fluorine-based and non-diene-based elastomer.
23. The method according to claim 22 , wherein
a content of the hydrophobic polymer in the solid state electrolyte layer is from 0.01% to 30% by weight.
24. A solid state electrolyte layer comprising:
a sulfide solid state electrolyte material that is manufactured from a raw material composition containing Li 2 S and P 2 S 5 and includes no more than 10 mol % of a bridging sulfur of an S 3 P—S—PS 3 unit; and
a hydrophobic polymer for binding the sulfide solid state electrolyte material,
wherein
the hydrophobic polymer is free of a hydrophilic group,
the hydrophobic polymer is at least one selected from the group consisting of styrene-ethylene-butadiene, butyl rubber, isoprene rubber, ethylene-propylene-diene rubber, olefin-based and non-diene-based elastomer, and fluorine-based and non-diene-based elastomer, and
a content of the hydrophobic polymer in the solid state electrolyte layer is from 0.01% to 30% by weight.