Lithium electrodes with and without CO_2 treatment: electrochemical behavior and effect on high rate lithium battery performance

摘要

The ionic resistivity and integrity of a solid-electrolyte interphase (SEI) film on a lithium electrode surface was investigated. The preformed lithium carbonate film on the surface of the lithium electrode was found to improve the electrode behavior by maintaining a low ionic resistance. In lithium/silver vanadium oxide batteries, voltage delay can be eliminated with the use of a lithium anode pretreated with CO_2. An SEI consisting of lithium carbonate appears to be responsible. Unlike the surface film formed from lithium-electrolyte reactions, the lithium carbonate film is relatively strong and can withstand high current density pulses ( ～ 20 mA/cm~2) without significant damage. An ion exchange mechanism involving the carbonate anion is proposed.