Abstract:Lithium iron phosphate precursor was synthesized by coprecipitation method applying ferrous sulfate, phosphoric acid and lithium hydroxide as raw materials. High-rate lithium iron phosphate composite material (LiFePO4/C) was obtained after calcination. Effects of temperature on morphology and electrochemical properties of precursor during calcination were studied. The results show that the output phase calcined at 750 ℃ is lithium iron phosphate with good spherical morphology and has the best electrochemical performance with conductivity of 5.10 S/m, tap density of 1.19 g/cm3, and the first discharge specific capacity of 145.8 mAh/g at 0.1C rate. Its internal resistance is 139.64 Ω, cyclic volt-ampere curve is up and down in symmetrical with good cycle reversibility.