Multilayer anodes for lithium-based energy storage devices
A method of making an anode for an energy storage device such as a lithium-ion energy storage device is disclosed. The method may include depositing a first lithium storage layer over a current collector by a first CVD process. The current collector may include a metal oxide layer, and the first lithium storage layer is deposited onto the metal oxide layer. The method may also include forming a first intermediate layer over at least a portion of the first lithium storage layer. The method may further include depositing a second lithium storage layer over the first intermediate layer by a second CVD process. At least the first lithium storage layer may be a continuous porous lithium storage layer having a total content of silicon, germanium, or a combination thereof, of at least 40 atomic %.
1. A method of making an anode for use in an energy storage device, the method comprising:
depositing a first lithium storage layer over a current collector by a first CVD process, wherein the current collector comprises a metal oxide layer and the first lithium storage layer is deposited onto the metal oxide layer;
forming a first intermediate layer over at least a portion of the first lithium storage layer; and
depositing a second lithium storage layer over the first intermediate layer by a second CVD process,
wherein at least the first lithium storage layer is a continuous porous lithium storage layer comprising a total content of silicon, germanium, or a combination thereof, of at least 40 atomic %.
2. The method of claim 1 , wherein the continuous porous lithium storage layer comprises at least 85 atomic % amorphous silicon, and the continuous porous lithium storage layer has a density in a range of 1.1 g/cm 3 to 2.2 g/cm 3 .
3. The method of claim 1 , wherein the continuous porous lithium storage layer is a first continuous porous lithium storage layer, the second lithium storage layer is a second continuous porous lithium storage layer comprising a total content of silicon, germanium, or a combination thereof, of at least 40 atomic %.
4. The method of claim 1 , wherein the continuous porous lithium storage layer is a first continuous porous lithium storage layer, the second lithium storage layer is a second continuous porous lithium storage layer comprising at least 85 atomic % amorphous silicon.
5. The method according of claim 1 , wherein one or both of the first CVD process and the second CVD process comprise PECVD.
6. The method of claim 1 , wherein one or both of the first lithium storage layer and the second lithium storage layer have an average thickness of at least 3 μm.
7. The method of claim 1 , wherein forming the first intermediate layer comprises depositing an electrically conductive metal onto the first lithium storage layer.
8. The method of claim 7 , wherein the electrically conductive metal comprises a transition metal.
9. The method of claim 8 , wherein the transition metal is nickel, titanium, copper, or zinc.
10. The method of claim 7 , further comprising oxidizing at least a portion of the metal to form the first intermediate layer comprising a metal oxide.
11. The method of claim 7 , wherein the metal is deposited by vapor deposition, sputtering, or a CVD process.
12. The method of claim 1 , wherein forming the first intermediate layer comprises depositing a metal oxide, a metal nitride, a metal oxynitride, a metal sulfide, or a metal oxysulfide.
13. The method of claim 12 , wherein the metal oxide, the metal nitride, the metal oxynitride, the metal sulfide, or the metal oxysulfide comprises a transition metal.
14. The method of claim 12 , wherein the deposition of the metal oxide, the metal nitride, the metal oxynitride, the metal sulfide, or the metal oxysulfide comprises vapor deposition, sputtering, atomic layer deposition, or a CVD process.
15. The method of claim 1 , wherein forming the first intermediate layer comprises depositing a solution or dispersion comprising an intermediate layer material or precursor over the first lithium storage layer.
16. The method of claim 1 , wherein forming at least one intermediate layer comprises a patterning process.
17. The method of claim 16 , wherein the patterning process comprises patterned printing, photolithography, or vapor deposition through a shadow mask.
18. The method of claim 1 , further comprising thermally treating the anode after deposition of the second lithium storage layer is complete and prior to battery assembly,
wherein the thermally treating includes heating the anode to a temperature in a range of 100° C. to 600° C. for a time period in a range of 0.1 min to 120 min.
19. The method of claim 1 , wherein the metal oxide layer comprises a tin oxide or a zinc oxide.