文摘
Nanoscale LiFePO4/C particles are synthesized using a combination of electrospinning and annealing. The important advantages of electrospinning technique are the production of separated nanofiber precursor, enabling the precursor particles arrangement to be changed, impeding the growth and agglomeration of the LiFePO4 particles during the heat treatment, and contributing to the formation of nanosized LiFePO4 particles. In this study, polyvinylpyrrolidone (PVP) is used as the fiber-forming agent in the electrospinning method, and also provides a reducing agent and carbon source. In situ carbon-coated LiFePO4 particles are obtained by the pyrolysis of PVP during the thermal treatment. The LiFePO4 particles are coated with and connected by interlaced carbons, and are uniformly distributed in the size range 50-0?nm. It is found that the as-prepared nanoscale LiFePO4/C composite has a desirable electrochemical performance. It has discharge capacities of 163.5?mA?h g? and 110.7?mA?h g? at rates of 0.1?C and 10?C, respectively. In addition, this cathode has excellent cyclability with a capacity loss of less than 3?% at 0.1?C and 5?% at 5?C after 500 cycles. An effective synthesis and processing method is presented for obtaining nanosized LiFePO4 with high electrochemical performance.