Dry process formation of solid state lithium ion cell
Methods for preparing an electrode may include compressing an electrode dry mixture comprising an active material and an electrolyte material to form an electrode film. An electrolyte dry mixture or a stand-alone solid-state electrolyte film is compressed against a surface of the electrode film to form a laminate of an electrolyte layer and the electrode film. The electrolyte dry mixture may include the electrolyte material. Compressing the electrode dry mixture may include calendering the electrode dry mixture. Compressing the electrolyte dry mixture or stand-alone electrolyte film may be accomplished also by calendering. The electrolyte material may include a glass ceramic and, optionally, an air-stabilizing dopant. The glass ceramic may include Li 3 PS 4 . Thus, the electrodes may include a composite cathode and a solid-state electrolyte layer. The methods may be applicable for a solvent-free process to form electrodes and electrochemical cells and batteries including the electrodes.
1. An electrode comprising an electrode dry mixture and a dry electrolyte material intermixed with the electrode dry mixture; and a binder intermixed with said electrode dry mixture and said dry electrolyte material, said binder in the form of fibrils;
wherein the electrode dry mixture comprises an active material, and
wherein said dry electrolyte material comprises from 0.1% to 15% by weight air-stabilizing dopant, based on the total weight of the dry electrolyte material.
2. The electrode of claim 1 , wherein the active material comprises nickel manganese cobalt, lithium manganese spinel, lithium nickel manganese spinel, lithium nickel cobalt aluminum oxide, lithium iron phosphate, lithium iron manganese phosphate, lithium cobalt oxide, graphite, or combinations thereof; and
the dry electrolyte material comprises a lithium phosphorus sulfide glass ceramic.
3. The electrode of claim 1 , wherein the dry electrolyte material comprises a glass ceramic.
4. The electrode of claim 1 , wherein the dry electrolyte material comprises a lithium phosphorous sulfide glass ceramic.
5. The electrode of claim 1 , wherein the dry electrolyte material comprises Li 3 PS 4 glass ceramic.
6. The electrode of claim 1 , wherein the air-stabilizing dopant is selected from the group consisting of ZnO, CaO, ZrS 2 , and combinations thereof.
7. The electrode of claim 1 , wherein the active material comprises nickel manganese cobalt, lithium manganese spinel, lithium nickel manganese spinel, lithium nickel cobalt aluminum oxide, lithium iron phosphate, lithium iron manganese phosphate, lithium cobalt oxide, graphite, or combinations thereof.
8. The electrode of claim 1 , wherein the electrode further comprises a second electrolyte dry mixture compressed against a surface of the electrode to form an electrolyte layer on the surface of the electrode film, the second electrolyte dry mixture comprising the dry electrolyte material.
9. The electrode of claim 8 , wherein the second electrolyte dry mixture further comprises an electrolyte binder chosen from fibrillizable polymers, polytetrafluoroethylene, and poly(vinylidene fluoride), ultra-high molecular weight polypropylene, polyethylene, and copolymers or blends thereof.
10. The electrode of claim 1 , wherein:
the active material comprises lithium cobalt oxide or nickel manganese cobalt;
the dry electrolyte material comprises Li 3 PS 4 glass ceramic; and
the binder comprises a fibrillizable polymer binder chosen from polytetrafluoroethylene, and poly(vinylidene fluoride), ultra-high molecular weight polypropylene, ultra-high molecular weight polyethylene, and copolymers or blends thereof.
11. The electrode of claim 1 , wherein the electrode further comprises a stand-alone solid-state electrolyte film laminated against a surface of the electrode film;
wherein the stand-alone solid state electrolyte film comprises the dry electrolyte material.
12. The electrode of claim 1 , wherein said binder is present at 10 percent by weight or less of the total of said electrode dry mixture, said dry electrolyte material, and said binder combined.
13. An electrochemical cell comprising the electrode of claim 1 .
14. The electrochemical cell of claim 13 wherein the dry electrolyte material comprises a lithium phosphorus sulfide glass ceramic.
15. The electrochemical cell of claim 13 comprising an anode layer, wherein the anode layer is a Li foil protected on at least one surface with an anode protective layer, the anode protective layer comprising LiPON.