Effects of FEC Additive on the Low Temperature Performance of LiODFB-Based Lithium-Ion Batteries

The low temperature performance of LiFePO 4 /Li cells based on lithium oxalyldifluoroborate (LiODFB) with fluoroethylene carbonate (FEC) as addictive have been investigated. The result of ionic conductivity test shows that the use of 5% FEC can improve the conductivity of both LiPF 6 and LiODFB electrolytes at low temperature. The electrochemical measurements of the cells show that the use of FEC can effectively improve the discharge capacity and has better kinetics characteristics and low temperature performance. The LiODFB cell with FEC also exhibits excellent cycling retention of 88.8% after 50 cycles at-20°C.