Rechargeable Lithium Batteries

Carbon-coated lithium iron phosphate (LiFePO4/C) composites are synthesized by the modified mechanical activation method (modified MA process) and studied by the Rietveld structural refinement. Rietveld indices of LiFePO4/C indicate good fitting with Rp = 8.14%, Rwp = 11.1%, Rexp = 9.09%, RB = 3.88%, and S (GofF, Goodness of fit) = 1.2, respectively. LiFePO4/C with a space group Pnma shows a = 10.3229(3) Å, b = 6.0052(2) Å, c = 4.6939(1) Å, and V = 290.98(1) Å 3 in dimension, indicating good agreements with those of previous works. Synthetic powders are nano-sized (65∼90 nm) homogeneous particles with high purity. Thus the modified MA method will be an efficient process to get a high quality cathode material for commercial lithium batteries.