Method for alkaliating anodes
The present invention relates to a method for lithiation of an intercalation-based anode or a non-reactive plating-capable foil or a reactive alloy capable anode, whereby utilization of said lithiated intercalation-based anode or a plating-capable foil or reactive alloy capable anode in a rechargeable battery or electrochemical cell results in an increased amount of lithium available for cycling, and an improved reversible capacity during charge and discharge.
1. A method for pre-lithiation of an anode comprising the steps of:
(a) providing an anode;
(b) contacting said anode with a bath comprising dissolved carbon dioxide, lithium chloride, and gamma-butyrolactone in an amount sufficient to solubilize the lithium chloride, and wherein a dry gas blanket covers said bath;
(c) providing an electrolytic field plate comprising an inert conductive material wherein said field plate establishes a field between the anode and the field plate; and
(d) applying a reducing current to the anode and an oxidizing current to the field plate, wherein lithium ions from the bath lithiate into the anode.
2. The method of claim 1 , wherein the anode comprises an anode active material selected from carbon, coke, graphite, tin, tin oxide, silicon, silicon oxide, aluminum, lithium-active metals, alloying metal materials, and mixtures thereof.
3. The method of claim 1 , wherein the electrolytic field plate is selected from platinum, gold, glassy carbon, and graphite.
4. The method of claim 1 , further comprising the step of assembling a rechargeable battery with the lithiated anode.
5. The method of claim 4 , wherein the rechargeable battery further comprises a cathode not initially containing lithium.
6. The method of claim 1 , wherein evolving gas generated at the field plate is captured by a reflux unit.
7. The method of claim 1 , further comprising the step of heating said bath to a temperature of between 30° C. and 65° C. with at least one inline heater.
8. The method of claim 7 , wherein said temperature is about 40° C.
9. The method of claim 1 , further comprising rinsing the anode in a solvent in a separate immersion bath.
10. The method of claim 1 , further comprising the step of periodically recovering the lithium chloride by distilling the gamma-butyrolactone and subsequently rinsing the lithium chloride in a non-solvating fluid.
11. The method of claim 1 , wherein the anode is lithiated continuously.
12. The method of claim 1 , wherein the bath further comprises an additive to facilitate SEI formation.
13. The method of claim 12 , wherein the additive is vinylene carbonate.