Rechargeable Lithium Batteries with Copper Vanadate Positives and Mixed Organic Electrolytes

Effects of mixed organic electrolyte on Li/Cu2V2O7 couple were investigated. From the conductivity and Li charge-discharge efficiency, 1M LiClO4-propylene carbonate (PC)/1,2-dimethoxyethane (DME) was selected as electrolyte. The prototype coin cells were fabricated to examine the properties of this cell system. Because of high electrolyte conductivity, the capacity at high discharge rate ( 3 mA/cm² ) was 450 Ah/(Cu2V2O7 weight) Kg, which was 1.8 times larger than the capacity of the cell with 1M LiClO4 / PC alone. The cycle life also improved from 10 cycles to 55 cycles at the condition of 2e⁼/Cu2V2O7 depth by the use of the PC/DME compared with PC alone. Copper vanadate with mixed electrolyte seems to be a very promissing cell system for practical utilization.