Nickel catalyzed graphitized carbon coated LiFe1-xNixPO4 composites as cathode material for high-performance lithium-ion batteries

Abstract

Olivine LiFePO4 (LFP) is considered as the most promising cathode material for commercial lithium-ion batteries (LIBs) due to its stable structure and environmental friendliness. However, the low Li+ diffusion coefficients and electron conductivity severely limit its practical application. Herein, nickel catalytic graphitization carbon coating LiFe1-xNixPO4 is successfully prepared by a simple one-pot method, which not only achieve higher graphitization carbon coating, but also lead to minor nickel doped into LiFePO4 lattice. The effect of the nickel catalytic graphitization and the minor nickel doped on the rate performance and cycling stability are investigated. As a result, the optimized LFNP@GC-3 composite deliver high capacity of 181.9 and 123.2 mAh g−1 at 0.1 and 5 C, and also exhibits high capacity retention of 95.6% after 500 cycles. The excellent Li-ion storage performance can be ascribed to Ni catalytic graphitization carbon coating and nickel doped, which lead to high electron conductivity and enlarge the lithium ion diffusion channel. The results of this study not only offer a practical way to realize the excellent performance of lithium ion storage, but also provide a versatile cathode for the promising lithium based energy storage devices.