Improved Electrochemical Performance of Carbon-Coated LiFeBO3 Nanoparticles for Lithium-Ion Batteries.

Carbon-coated LiFeBO3 nanoparticles have been successfully prepared by surfactant-assisted ball milling and a size selection process based on centrifugal separation. Monodispersed LiFeBO3 nanoparticles with dimensions of 10-20 nm are observed by transmission electron microscope. The introduced surfactant acts as the dispersant as well as the carbon source for LiFeBO3 nanoparticles. Greatly improved discharge capacities of 190.4 mA h g(-1) at 0.1 C and 106.6 mA h g(-1) at 1 C rate have been achieved in the LiFeBO3 nanoparticles when cycling the cells between 1.0 V and 4.8 V. Meanwhile, the as-prepared micro-size LiFeBO3 electrodes show lower discharge capacities of 142 mA h g(-1) and 93.3 mA h g(-1) at 0.1 C and 1 C rates. The post-treated LiFeBO3 nanostructure has drastically enhanced the electrochemical performance due to the short diffusion length and ameliorated electrical contract between LiFeBO3 nano particles.