Improving electrochemical performance of LiMnPO4 by Zn doping using a facile solid state method

Olivine structure LiMnPO4/C as cathode materials for Li-ion batteries were synthesized via a simple solid-state reaction. Improvement of the electrochemical performance of LiMnPO4/C cathode material was realized significantly by the method of doping Zn. The obtained LiMn0.95Zn0.05PO4/C electrode material was studied by the measurements of X-ray diffraction pattern, scanning electronic microscopy, electrochemical impedance spectroscopy and electrochemical performance. The results indicate that the LiMn0.95Zn0.05PO4/C materials exhibit discharge specific capacity of 140.2 mA h g(-1) at 0.02 C rate and better rate capability. These excellent results are elucidated by EIS test, which showed that there was the decrease of charge transfer resistance and faster lithium-ion diffusion in LiMnPO4/C cathode materials after Zn doping.