We prepared a LiFePO4/C composite using wet-milling assisted carbothermal reduction, and investigated how the ball-to-powder weight ratio affected the characteristics of the composite using X-ray diffraction (XRD), scanning electron microscopy (SEM), laser particle-size distribution measurements, and electrochemical performance testing. Four ball-to-powder weight ratios varying from 15:1 to 30:1 were compared. LiFePO4 surrounded by a network of carbon was obtained for all of the ball-to-powder weight ratios used. As the ball-to-powder weight ratio increased, the particles became more homogeneous, while the particle sizes of the slurries first decreased and then increased. The LiFePO4/C sample we prepared with a ball-to-powder weight ratio of 25:1 was mostly composed of similar to 50 nm particles. Electrochemical tests indicated that the sample had a discharge capacity of 125 mAh g(-1) with no capacity loss after 100 cycles at a 10C rate. This outstanding rate capability is mainly ascribed to the presence of nanoparticles with proper carbon structures and correspondingly reduced electrochemical polarization resistance. (C) 2013 Elsevier B.V. All rights reserved.