Synthesis of NixCo(1−x)F2 (x = 0, 0.25, 0.50, 0.75, 1.0) and application in lithium ion batteries

Abstract

In this work, NixCo(1−x)F2 with x = 0, 0.25, 0.5, 0.75 and 1.0 have been successfully synthesized. A specific discharge capacity of 700 mAhg−1 and recharge capacity of 482 mAhg−1 was delivered by Ni0.75Co0.25F2 in the first cycle. Our electrochemical results in lithium half-cell have shown that nickel containing fluorides have a higher discharge voltage, higher experimental discharge specific capacities and smaller hysteresis between the discharge and charge reactions as compared to pure cobalt fluoride. In addition, this work also presents a method to tune the discharge voltage and eliminate the voltage delay effect commonly observed in metal fluorides via the use of solid solution.