Performance of Lithium Ion Cell Anode Graphites Under Various Cycling Conditions

Abstract

Graphites MCMB-2810 and OMAC-15 (made by Osaka Gas Inc.), and SNG12 (Hydro Quebec, Inc.) were evaluated in lithium half-cells as anode materials for lithium-ion cells intended for use in hybrid electric vehicles. Though the reversible capacity obtained for SNG was slightly higher than that of OMAC or MCMB, its 1st cycle efficiency was considerably lower. Voltage vs capacity plots of cycling data show that the discharge and charge limits shift to higher capacity values due to continuation of anode side reactions. Varying the cycle charge and discharge limits was found to have an insignificant effect on fractional capacity shift per cycle.