In this study, the rate performance of a LiFePO4 (LFP) electrode has been enhanced by optimization of the particle size distribution of the LFP particles. Two LFP samples with different particle sizes (similar to 50 and similar to 350 nm) are mixed with various ratios and the electrochemical performance has been evaluated. Reduction of the contact resistance and increase of the Li diffusion coefficient have been achieved. The electrode with a mixing ratio of 50:50 shows an improved initial capacity at C/10 and superior rate capability compared with the two pristine materials. (C) 2019 The Electrochemical Society.