MnOx-Carbon Black-embedded LiFePO4 (MnOx/C-LFP) as a Cathode Material for High-Power Li-Ion Batteries

Abstract

LiFePO4 is a promising, cost-effective, and safe material for large-scale energy-storage applications, however its low intrinsic conductivity requires improvement. In order to address this issue, herein, we describe the successful sol-gel synthesis of MnOx-carbon black-embedded LiFePO4 (MnOx/C-LFP). Bare LiFePO4 and MnOx/C-LFP composites were characterized by scanning electron and high-resolution transmission electron microscopies, as well as X-ray diffraction, which revealed LiFePO4 particles embedded in the cross-linked MnOx/C matrix. Electrochemical studies show that the composite has a superior initial discharge capacity of 151.4 mAh/g at 1C, and a good capacity retention of 96.6% after 100 cycles, compared to the bare material (141.2 mAh/g and 92%). The improvement in electrochemical performance is attributed to facile lithium-ion diffusion through MnOx/C nanoparticles on the surface of the LiFePO4 cathode material. The co-coating of MnOx and carbon black is an effective way of improving the electrochemical kinetics of cathode materials.