Anodes for lithium-based energy storage devices, and methods for making same
A method of making a prelithiated anode for use in a lithium-ion battery includes providing a current collector having an electrically conductive layer and a metal oxide layer overlaying the electrically conductive layer. The metal oxide layer has an average thickness of at least 0.01 μm. A continuous porous lithium storage layer is deposited onto the metal oxide layer by a CVD process. Lithium is incorporated into the continuous porous lithium storage layer to form a lithiated storage layer prior to a first electrochemical cycle when the anode is assembled into the battery. The anode may be incorporated into a lithium ion battery along with a cathode. The cathode may include sulfur or selenium and the anode may be prelithiated.
1. A method of making a prelithiated anode for use in a lithium-ion battery, the method comprising:
providing a current collector comprising an electrically conductive layer and a metal oxide layer overlaying the electrically conductive layer, wherein the metal oxide layer has an average thickness of at least 0.01 μm;
depositing a continuous porous lithium storage layer onto the metal oxide layer by a CVD process; and
incorporating lithium into the continuous porous lithium storage layer to form a lithiated storage layer prior to a first electrochemical cycle of a battery comprising the anode.
2. The method of claim 1 , wherein incorporating lithium comprises depositing a lithiation material over the continuous porous lithium storage layer.
3. The method of claim 2 , wherein the lithiation material comprises a reducing lithium compound, lithium metal, or a stabilized lithium metal powder.
4. The method of claim 2 , further comprising applying heat or pressure to the anode during or after deposition of the lithiation material.
5. The method of claim 1 , wherein incorporating lithium comprises contacting the anode with a coating on a lithium transfer substrate, wherein the coating comprises a lithiation material.
6. The method of claim 5 , wherein the lithiation material comprises a reducing lithium compound, lithium metal, or a stabilized lithium metal powder.
7. The method of claim 5 , further comprising applying heat or pressure to the anode during contacting.
8. The method of claim 1 , wherein incorporating lithium comprises contacting the continuous porous lithium storage layer with a solution comprising a reductive lithium organic compound.
9. The method of claim 1 , wherein incorporating the lithium comprises electrochemical reduction of lithium ion in prelithiation solution.
10. The method of claim 1 , further comprising forming a supplemental layer over the continuous porous lithium storage layer prior to forming a lithiated storage layer, wherein the supplemental layer comprises silicon nitride, a metal oxide, a metal nitride, or a metal oxynitride.
11. The method of claim 1 , wherein incorporating lithium into the continuous porous lithium storage layer to form a lithiated storage layer comprises:
(a) depositing a lithium metal layer over the continuous porous lithium storage layer; and
(b) depositing a lithium-ion conducting layer after depositing the lithium metal layer.
12. The method of claim 11 , further comprising applying heat to the anode i) between steps (a) and (b), ii) after step (b), or iii) both (i) and (ii).
13. The method claim 11 , wherein the lithium ion-conducting layer comprises at least one of a lithium phosphorous oxynitride (LIPON), a lithium phosphate, a lithium aluminum oxide, a lithium lanthanum titanate, an alucone, or a zircone.
14. The method of claim 1 , wherein the CVD process is a PECVD process, and the continuous porous lithium storage layer comprises at least 85 atomic % amorphous silicon having a density in a range of 1.1 g/cm 3 to 2.2 g/cm 3 .
15. The method of claim 1 , wherein the metal oxide layer comprises an oxide of nickel or an oxide of titanium.
16. The method of claim 1 , wherein the lithiated storage layer includes lithium in a range of 10% to 100% of the theoretical lithium storage capacity of the continuous porous lithium storage layer.
17. A lithium-ion battery comprising a cathode and an anode having a lithiated storage layer, wherein the anode is made by the method of claim 1 .
18. The lithium-ion battery of claim 17 , wherein the cathode comprises sulfur, selenium, or both sulfur and selenium.
19. The lithium-ion battery of claim 18 , wherein the cathode further comprises carbon nanotubes.
20. The lithium-ion battery of claim 17 , wherein the lithiated storage layer includes lithium in a range of 50% to 100% of the theoretical lithium storage capacity of the continuous porous lithium storage layer.