Abstract: Mechanical ball milling method was used to prepare pyrite (FeS₂) powder,and then heat-treatment was taken to improve the electrochemical performance of FeS₂.Influences of different heat-treatment temperatures on bulk density and FeS₂ content of the products were investigated.Structure of the prepared FeS₂ was characterized by XRD and SEM and its electrochemical performance was tested by charge-discharge tester.Results showed that with raising of temperature the marcasite phase faded away gradually;it had only pyrite phase above 200 ℃;after heat-treatment at 400 ℃,the electrochemical performance test showed that the discharge capacities were 450,500,670 mA•h/g under current density of 0.2,0.5,3 mA/cm²,respectively.

Key words: pyrite(FeS₂）, heat-treatment, electrochemical property