Enhancing Lithium Ion Batteries through Cation Doping and Graphene Coating

Abstract

LiFeP0.1 has emerged as one of the most promising cathode materials for lithium ion batteries for a large variety of applications from smart phones and power tools. to electric vehicles. However. poor electronic conductivity and low lithium ion diffusion rate hinders its large-scale applications. It has been demonstrated that the electronic conductivity of LiFePO􀀫 can be improved by several methods, including powder size reduction. carbon layer coating, and lattice eloping. In this research. we investigate the effect brought by the combination of cation eloping and carbon layer coating. Zr or Ti cation eloped LifeP04 is synthesized using solid-state reaction. Graphene or glucose is used as a carbon coating agent. Phase and morphology of as-prepared powder are characterized by X-ray diffraction. Electrochemical properties are characterized by charge-discharge measurement at various rate. Results of these measurements were analyzed and arc represented in Figure IO and Figure I I. which display the spcci lie discharge and charge capacity per milliamperes an hour per gram (mAh/g) lor a 55-cyclc number. These results determined that LiFeP04 with a glucose carbon coating agent was the cathode material with the best and most consistent results.