Synthesis of Nanometric LiMnPO4 via a Two-Step Technique

A two-step procedure for preparation of LiMnPO 4 with small particle size (15–20 nm) and embedded in a carbon matrix is presented. The crucial point that prevents excessive particle growth is the avoidance of lithium in the first firing step, so that small Mn 2 P 2 O 7 particles embedded in carbon are obtained. Because of the carbon matrix, the Mn 2 P 2 O 7 particles also cannot grow in the second step, which involves lithiation and heating to 700 °C in argon. The prepared LiMnPO 4 shows a high theoretical capacity (up to 95% of the theoretical value) and a stable cycling (>130 mAh/g, even after 100 cycles at 55 °C and a rate of C/20). At room temperature and using the CC–CV mode, the performance is comparable to the best result shown in the literature so far. Finally, the performance of LiMnPO 4 is briefly compared with that of LiFePO 4 .