Low temperature synthesis of graphene-wrapped LiFePO4nanorod cathodes by the polyol method

Abstract

A facile, low temperature polyol method is developed to synthesize graphene-wrapped, rod-shaped LiFePO₄ (LFP) cathode materials. The effects of reaction temperature and reduced graphene oxide (RGO) on the morphology and electrochemical performance of RGO/LFP composites are studied. The RGO/LFP containing 10 wt% precursor GO and synthesized at 220 °C presents the best electrochemical properties, namely discharge specific capacities of 164.1, 156.7 and 121.5 mA h g⁻¹ after 100 cycles with capacity retention ratios of 99.0, 97.9 and 98.6% at 0.1 C, 1 C and 10 C, respectively. These values are considered among the highest reported in the literature for LFP cathodes with similar carbon additives. The improved electronic conduction and reduced charge transfer resistance arising from the RGO sheets are responsible for the excellent electrochemical properties.