Interface design for high current density cycling of solid state battery
Solid-state batteries offer improved safety and the high-energy-density capabilities required for next generation demands of electric vehicles. Disclosed is a method for fabricating high-current-density solid-state batteries, and the associated device structures and systems. The method of fabrication includes purifying surfaces of a solid electrolyte, depositing materials to form deposition layers on the surfaces of the solid electrolyte in a vacuum, and forming oxygen-deficient interfaces at the interface of the deposition layers and the solid electrolyte. The methods and associated devices form high-current-density solid-state batteries with stable electrochemical performance over hundreds of electric cycles.
1. A solid-state battery cell, comprising:
a first electrode comprising lithium metal or a lithium metal alloy, the first electrode having a first electrode first surface and an oppositely disposed first electrode second surface;
a second electrode having a second electrode first surface and an oppositely disposed second electrode second surface;
a solid electrolyte comprising a cubic lithium ion conducting metal oxide, the solid electrolyte extending between the first and second electrodes and the solid electrolyte having oppositely disposed first and second electrolyte surfaces, wherein the first electrolyte surface is in facing relation to the first electrode second surface and the second electrolyte surface is in facing relation to the second electrode first surface; and
a first oxygen-deficient interface layer formed by reduction of the first electrolyte surface of the solid electrolyte, the first oxygen-deficient interface layer formed in the solid electrolyte at an interface between the first electrolyte surface and the first electrode second surface, and the first oxygen-deficient interface layer extending only partially through the solid electrolyte, wherein the solid electrolyte has an ionic conductivity in the range of 0.1×10 −3 to 10×10 −2 S/cm at temperatures of 66° F. to 74° F., wherein the oxygen-deficient layer has a thickness of less than 10 nm.
2. The solid-state battery cell of claim 1 , wherein the second electrode comprises one or more of lithium nickel manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt aluminum oxide, or lithium iron phosphate.
3. The solid-state battery cell of claim 1 , wherein the electrolyte comprises lithium lanthanum zirconium oxide (LLZO).
4. The solid-state battery cell of claim 1 , wherein the electrolyte is doped with one or more of aluminum, tantalum, and niobium.
5. The solid-state battery cell of claim 1 , further comprising a second oxygen-deficient interface layer disposed between the second electrolyte surface and the second electrode first surface.
6. The solid-state battery cell of claim 1 , further comprising a first deposition layer disposed between the first electrode and the electrolyte such that the first oxygen-deficient interface layer is disposed between the first deposition layer and the first electrolyte surface.
7. The solid-state battery cell of claim 6 , wherein the first deposition layer is deposited in a vacuum.
8. The solid-state battery cell of claim 6 , further comprising:
a first lithium layer physically coupled to the first deposition layer, wherein the first lithium layer is in electrical communication with the first deposition layer.
9. The solid-state battery cell of claim 1 , wherein the solid-electrolyte comprises a material having a crystalline structure.
10. The solid-state battery cell of claim 1 , wherein the solid electrolyte comprises at least one of doped lithium lanthanum zirconium oxide (LLZO), undoped LLZO, doped lithium lanthanum titanium oxide (LLTO), and undoped LLTO.
11. The solid-state battery cell of claim 10 , wherein the solid electrolyte comprises doped LLZO.
12. The solid-state battery cell of claim 10 , wherein the solid electrolyte comprises undoped LLZO.
13. The solid-state battery cell of claim 10 , wherein the solid electrolyte comprises doped LLTO.
14. The solid-state battery cell of claim 10 , wherein the solid electrolyte comprises undoped LLTO.
15. A solid-state battery cell, comprising:
a first electrode comprising lithium;
a second electrode comprising one or more of lithium nickel manganese cobalt oxide, lithium nickel cobalt aluminum oxide, or lithium nickel manganese oxide;
a solid electrolyte extending between the first and second electrodes, the solid electrolyte comprising cubic lithium lanthanum zirconium oxide (LLZO);
a first lithium deposition layer on a first surface of the solid electrolyte, wherein the first deposition layer extends between the first electrode and the first surface of the solid electrolyte; and
an oxygen-deficient interface at an interface of the first lithium deposition layer and the first surface of the solid electrolyte and formed by reduction of the first surface of the solid electrolyte, the oxygen deficient interface extending only partially through the solid electrolyte, wherein the solid electrolyte has a conductivity in the range of 0.1×10 −3 to 10×10 −2 S/cm at temperatures of 66° F. to 74° F., wherein the oxygen-deficient layer has a thickness of less than 10 nm.
16. A solid-state battery cell, comprising:
a first electrode comprising lithium metal or a lithium metal alloy, the first electrode having a first electrode first surface and an oppositely disposed first electrode second surface;
a second electrode having a second electrode first surface and an oppositely disposed second electrode second surface;
a solid electrolyte comprising a cubic lithium ion conducting metal oxide, the solid electrolyte extending between the first and second electrodes and the solid electrolyte having oppositely disposed first and second electrolyte surfaces, wherein the first electrolyte surface is in facing relation to the first electrode second surface and the second electrolyte surface is in facing relation to the second electrode first surface;
a first oxygen-deficient interface layer formed by reduction of the first electrolyte surface of the solid electrolyte, the first oxygen-deficient interface layer formed in the solid electrolyte at an interface between the first electrolyte surface and the first electrode second surface, and the first oxygen-deficient interface layer extending only partially through the solid electrolyte, wherein the solid electrolyte has an ionic conductivity in the range of 0.1×10 −3 to 10×10 −2 S/cm at temperatures of 66° F. to 74° F.; and
a first deposition layer disposed between the first electrode and the electrolyte such that the first oxygen-deficient interface layer is disposed between the first deposition layer and the first electrolyte surface,
wherein the first deposition layer is deposited in a vacuum.