Carbon-coated LiMn0.8Fe0.2PO4 cathodes for high-rate lithium-ion batteries

Electrode materials are a decisive factor in determining the specific energy of lithium batteries. Lithium iron phosphate/graphite systems are among the most widely used and safest lithium batteries currently available. However, due to the lower voltage plateau of lithium iron phosphate and the near-theoretical limit of specific capacity achieved by the lithium iron phosphate/graphite system, it is challenging to meet the demands of high energy density lithium batteries. Lithium manganese iron phosphate (LiMn 0.8 Fe 0.2 PO 4 ) emerges as a promising next-generation cathode material to replace lithium iron phosphate. However, its low electronic conductivity necessitates improvements through surface coating and carbon compositing to enhance the material's conductivity. This paper presents the synthesis of carbon-coated LiMn 0.8 Fe 0.2 PO 4 electrode materials via a solid-state method. By adding a conductive carbon layer on the material's surface and nanosizing, the electronic conductivity of the electrode is significantly enhanced, improving lithium-ion diffusion, and thereby boosting the charge–discharge efficiency and power output of the battery. This technique offers an effective pathway for optimizing and advancing lithium-ion batteries.