High Rate Capability of a Dual-Porosity LiFePO₄/C Composite

Abstract

Mesoporous intercalation compounds consisting of two different distributions of pores represent a potentially attractive material for high-rate cathodes. A mesoporous LiFePO4/C composite with two sizes of pores is prepared for the first time via a solution-based polymer templating technique. The precursor of the LiFePO4/C composite is heated at different temperatures in the range from 600 to 800 °C to study the effect of crystallinity, porosity, and morphology on the electrochemical performance. The composite is found to attain reduction in the surface area, carbon content, and porosity upon increasing temperature. Nonetheless, the composite prepared at 700 °C with pore-size distributions of around 4 and 50 nm exhibits a high rate capability and stable capacity retention upon cycling.