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In this thesis, we prepared carbon materials by pyrolysis of agriculture crop residues and used to synthesize LiFePO4/C composites. The advantages of pyrolytic carbons from above are low cost and environmentally benign. Furthermore, the pyrolytic carbons treated with poregenic agent gave both high surface area (>2000 m2/g) and high porosity. Hence, we adopted a solid state method to obtain olivine structural LiFePO4 fine powders and mixed small amount of high surface area carbon into the product to improve the electronic conductivity. The electrochemical studies concluded the optimum calcination process for the synthesized LiFePO4/C composites were 600oC for 12 h in Ar/H2 (vol. 95:5) gas with addition of 8.0 wt.% high surface area carbon. The LiFePO4/C composite delivered a discharge capacity of 140 mAhg-1 in the first cycle at a 0.2C-rate between 4.3 to 2.5 V, and he number of cycles sustained was 456 cycles at a preset cut-off value of 80% capacity retention. In the cyclability tests of LiFePO4 electrodes at different charging and discharging rates, the specific capacity decreases with increasing charge/discharge rate, and the capacity retention remains very good for all the different rates. Therefore, the high surface area carbon coated LiFePO4 electrodes demonstrated high capacity and good cyclability.