Anodes for lithium-based energy storage devices
An anode for a lithium-based energy storage device such as a lithium-ion battery is disclosed. The anode includes an electrically conductive current collector comprising an electrically conductive layer and a transition metal oxide layer overlaying the electrically conductive layer. The anode may include a continuous porous lithium storage layer provided over the transition metal oxide layer. The continuous porous lithium storage layer may include at least 80 atomic % amorphous silicon and a silicide-forming metallic element in a range of 0.1 to 10 atomic %. A method of making the anode may include providing an electrically conductive current collector having an electrically conductive layer and a transition metal oxide layer provided over the electrically conductive layer. The transition metal oxide layer may have an average thickness of at least 0.05 μm. A continuous porous lithium storage layer is deposited over the transition metal oxide layer by PECVD.
1. An anode for an energy storage device comprising:
an electrically conductive current collector comprising an electrically conductive layer and a metal oxide layer overlaying the electrically conductive layer; and
a continuous porous lithium storage layer overlaying the metal oxide layer, wherein the continuous porous lithium storage layer comprises at least 80 atomic % amorphous silicon and a silicide-forming metallic element in a range of 0.1 to 10 atomic %.
2. The anode of claim 1 , wherein the silicide-forming metallic element is in a range of 0.2 to 5 atomic %.
3. The anode of claim 1 , wherein the atomic % of the silicide-forming metallic element is higher near the current collector than away from the current collector.
4. The anode of claim 1 , wherein the silicide-forming metallic element is nickel.
5. The anode of claim 1 , wherein the metal oxide layer comprises a transition metal oxide.
6. The anode of claim 1 , wherein the metal oxide layer comprises an oxide of nickel, an oxide of titanium, or an oxide of copper.
7. The anode of claim 1 , wherein the metal oxide layer has an average thickness of at least 0.02 μm.
8. The anode of claim 1 , wherein the metal oxide layer comprises a gradient of oxygen content such that an atomic % of oxygen adjacent to the electrically conductive layer is lower than an atomic % adjacent to the continuous porous lithium storage layer.
9. The anode of claim 1 , wherein the metal oxide layer comprises a dopant.
10. The anode of claim 1 , wherein the continuous porous lithium storage layer has an average thickness in a range of 1 μm to 25 μm.
11. The anode of claim 1 , wherein the continuous porous lithium storage layer has an average thickness in a range of 2 μm to 15 μm.
12. The anode of claim 1 , wherein the continuous porous lithium storage layer has a total content of silicon of at least 90 atomic %.
13. The anode of claim 1 , wherein the continuous porous lithium storage layer has an average density in a range of 1.1 to 2.25 g/cm 3 .
14. The anode of claim 1 , further comprising a supplemental layer overlaying the continuous porous lithium storage layer.
15. The anode of claim 14 , wherein the supplemental layer comprises a metal oxide, a metal nitride, or a metal oxynitride.
16. The anode of claim 15 , wherein the supplemental layer comprises aluminum, titanium, vanadium, zirconium, or tin.
17. The anode of claim 14 , wherein the supplemental layer comprises a solid-state electrolyte.
18. The anode of claim 1 , wherein the continuous porous lithium storage layer further comprises germanium, tin, or antimony.
19. The anode of claim 1 , wherein the continuous porous lithium storage layer further comprises hydrogen, boron, or phosphorous.
20. A lithium-ion battery comprising the anode of claim 1 .