Porous, carbon-decorated LiFePO4 prepared by sol-gel method based on citric acid

A new type of LiFePO4-carbon composite cathode material was prepared. The active component consists of micrometer-sized particles containing pores with wide distribution of sizes. When filled with electrolyte, the pores are responsible for supply of ions while the distance between the pores (30-150 nm) determines the solid-state diffusion kinetics. The walls of pores are covered with a carbon layer which serves as an electron conductor and is thin enough (2-3 nm) to allow penetration of lithium ions. The synthesis is sol-gel based with a single heating step. The electrochemical performance is equal to the best-published results for LiFePO4 cathodes.