METHODS OF PRELITHIATING SILICON-CONTAINING ELECTRODES
Methods for prelithiating a silicon-containing electrode or electrodes, for example in the form of an electrode roll, are described herein. A method of prelithiating a silicon-containing electrode can include electrically connecting the silicon-containing electrode to a negative terminal of an electrical power source and immersing the silicon-containing electrode in a lithium salt solution. A lithium source can be connected to a positive terminal of the electrical power source and also immersed in the lithium salt solution. A current can be applied to the silicon-containing electrode to thereby intercalate the silicon-containing electrode with lithium. The silicon-containing electrode may comprise a current collector and may subsequently be used as an anode in a lithium-ion electrochemical cell.
1 . A method of prelithiating a silicon-containing electrode, the method comprising:
electrically connecting the silicon-containing electrode to a negative terminal of an electrical power source;
immersing the silicon-containing electrode in a lithium salt solution;
wherein a lithium source is immersed in the lithium salt solution such that it does not directly contact the silicon-containing electrode and the lithium source is electrically connected to a positive terminal of the electrical power source; and
applying a current from the electrical power source to the silicon-containing electrode for a duration until a desired level of lithium intercalation of the silicon-containing electrode is achieved.
2 . The method of claim 1 , wherein the silicon-containing electrode comprises a film comprising silicon and a carbon phase that holds the film together.
3 . The method of claim 2 , wherein the silicon-containing electrode further comprises silicon particles distributed within the carbon phase.
4 . The method of claim 2 , wherein the silicon-containing electrode further comprises a current collector, the film being in electrical communication with the current collector.
5 . The method of claim 4 , wherein the silicon-containing electrode is a rolled-type electrode.
6 . The method of claim 5 , wherein the silicon-containing electrode comprises and anode.
7 . The method of claim 1 , wherein applying the current from the electrical power source to the silicon-containing electrode results in a current density in the silicon-containing electrode of from about 0.05 mA/cm 2 to about 0.5 mA/cm 2 .
8 . The method of claim 1 , wherein the lithium source comprises lithium metal.
9 . The method of claim 8 , wherein the lithium source comprises lithium metal foil.
10 . The method of claim 1 , wherein the lithium salt solution comprises an organic lithium salt solution.
11 . The method of claim 10 , wherein the lithium salt solution comprises Li trans-trans-muconate (ttMA).
12 . The method of claim 1 , wherein the method is carried out at room temperature.
13 . The method of claim 1 , wherein the method is carried out in an ambient atmosphere.
14 . The method of claim 2 , further comprising brushing the film and exposing the film to blowing air prior to immersing the silicon-containing electrode in the lithium salt solution.
15 . The method of claim 1 , further comprising subjecting the silicon-containing electrode to a post treatment process, wherein the post treatment process comprises rinsing the silicon-containing electrode with water and drying the rinsed silicon-containing electrode.
16 . The method of claim 1 , wherein substantially no lithium metal is plated or deposited on the silicon-containing electrode.
17 . The method of claim 1 , wherein the prelithiated silicon-containing electrode is used as a component in a lithium-ion electrochemical cell.
18 . The method of claim 1 , wherein the silicon-containing electrode is a Si-dominant electrode.
19 . The energy storage device of claim 1 , wherein the silicon-containing electrode comprises a self-supporting composite material film.
20 . The energy storage device of claim 19 , wherein the composite material film comprises:
greater than 0% and less than about 90% by weight of silicon particles, and
greater than 0% and less than about 90% by weight of one or more types of carbon phases, wherein at least one of the one or more types of carbon phases is a substantially continuous phase that holds the composite material film together such that the silicon particles are distributed throughout the composite material film.