Synthesis, Characterization and Electrochemical Performance of Nb Doped LiFePO4/C Cathodes by Mechanochemical Activation

Abstract

We synthesized Nb-doped LiFePO4 /C nano composite cathode materials by mechanochemical activation followed by a single step calcination. The starting chemicals of Li2 CO3 , FeC2 O4 .2H2O, NH4 H2 .PO4 and C6 H8 O7 as lithium, iron, phosphate, and carbon sources are mixed in a high energy ball mill 250 rpm, 5h and calcined at 650 °C and 10 hours. The resultant materials are structurally XRD, SEM, TEM and electrochemically characterized and high purity LiFePO4 with high electrochemical performance is obtained. Voltage vs. specific capacity, discharge capacity vs. cycle number in manufactured battery is presented. An initial specific discharge capacity of 153 mAhg−1 and a specific discharge capacity of 128.4 mAhg−1 after the 8th charge/discharge cycling at 1C is recorded.

Keywords

• LiFePO4,Lithium ion battery,Mechanochemical activation,Nb doping

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