Positive electrode performance of nonflammable lithium secondary battery with ambient-temperature molten salt electrolyte

The positive electrode performance of the LiCoO2 electrode in the LiCl saturated AlCl3-1-ethyl-3-methylimizadolium chloride (EMIC) + SOCl2 melt as the electrolyte for nonflammable lithium secondary batteries was evaluated. In the cyclic voltammogram of the LiCoO2 electrode in the melt, the oxidation and reduction waves corresponding to the electrochemical intercalation / deintercalation reactions of Li+ were observed at 3.5-4.2 V vs. Li+/Li, and it suggested that the LiCoO2 electrode operated well in this melt. From charge and discharge evaluations, it was known that the discharge capacity was about 130 mAh g(-1) and the coulomb efficiency was maintained of more than 93% during ten cycles. It became clear that the LiCoO2 electrode operates quite as a positive electrode in the melt.