Single-Crystalline LiFePO₄ Nanosheets for High-Rate Li-Ion Batteries

The lithiation/delithiation in LiFePO₄ is highly anisotropic with lithium-ion diffusion being mainly confined to channels along the b-axis. Controlling the orientation of LiFePO₄ crystals therefore plays an important role for efficient mass transport within this material. We report here the preparation of single crystalline LiFePO₄ nanosheets with a large percentage of highly oriented {010} facets, which provide the highest pore density for lithium-ion insertion/extraction. The LiFePO₄ nanosheets show a high specific capacity at low charge/discharge rates and retain significant capacities at high C-rates, which may benefit the development of lithium batteries with both favorable energy and power density.