Synthesis and Electrochemical Characteristics of LiMnPO4/C Composite Materials for Lithium Ion Batteries

Olivine-structured LiMnPO₄ has attracted broad attention as a potential cathode material of Li-ion battery for EV application [1-2], which has some advantage with a higher energy density, higher redox potential and lower cost, etc. However, this material showed a poor electrochemical performance due to the low electronic conductivity [3-4]. Therefore, many researches have been performed to improve the electrochemical properties of LiMnPO₄ material by the particle size reduction, cation doping and carbon coating, etc. [5-6]. In here, we studied nano-sized LiMnPO₄/C composite materials with a high crystallization prepared using a modified co-precipitation method including a grinding mill and heat treatment process. As a result, the cell showed a good discharge capacity of 145mAh/g and a discharge potential of 3.8V. Furthermore, as the LiMnPO₄/C material was combined with Li₂MnO₃-based material, the LiMnPO₄/C composite materials showed a better electrochemical characteristic of above 200mAh/g at 0.05C. In summary, the nano-sized LiMnO₄ material with a high crystallization shows good electrochemical properties at room temperature.

References

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