MnO _x –Carbon Black-embedded LiFePO ₄ (MnO _x /C-LFP) as a Cathode Material for High-Power Li-Ion Batteries

LiFePO ₄ 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 MnO _x –carbon black-embedded LiFePO ₄ (MnO _x /C-LFP). Bare LiFePO ₄ and MnO _x /C-LFP composites were characterized by scanning electron and high-resolution transmission electron microscopies, as well as X-ray diffraction, which revealed LiFePO ₄ particles embedded in the cross-linked MnO _x /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 MnO _x /C nanoparticles on the surface of the LiFePO ₄ cathode material. The co-coating of MnO _x and carbon black is an effective way of improving the electrochemical kinetics of cathode materials.