Influences of carbon coating precursors on the electrochemical performance of graphite anodes in lithium-ion batteries
Wen-Jun Yuan, Xin Li, Jilun Li, Xiaofeng Zhang, Suna Lin, Xiaoyu Xu, Xinyi Wang, Ang Li, Xiaohong Chen, Huaihe Song
Abstract
Carbon coating modification has been proven to effectively improve the electrochemical performance of graphite anodes in Lithium-ion batteries (LIBs), especially enhancing the high-rate property. However, there is still a lack of in-depth exploration regarding the specific impact of different types of carbon coatings on the rapid charge/discharge rate of graphite anodes. This paper compares the effects of two different carbon coating agents—phenolic resin (PF, hard carbon precursor) and mesophase pitch (MP, graphitizable carbon precursor)—on the performance of graphite anodes. Different coated natural graphite (PF@G and MP@G) are prepared by varying the type of carbon material for comparison. Experimental results present that the PF@G with hard carbon coating exhibits best rate performance. Especially at 5C current density, PF@G has a reversible specific capacity of 112.6 mAh g −1 and retains a high reversible capacity after 500 cycles. The MP@G with graphitizable carbon coating shows the higher initial coulombic efficiency (ICE) and outstanding cycle stability. In particular, the capacity retention of MP@G is 88.8 % at 5C current density, demonstrating its excellent performance retention ability during high-rate charge and discharge processes. This provides valuable references for the design of high-performance LIB anode materials .