Paper Title
Enhancement On Rate Cycle Performance Of The Lithium Ion Battery Anode With Double Coated Surface Modification

Abstract
Natural graphite is characterized with higher capacity. However, its specific surface area (SSA) and poor rate cycle performance force it to be proceeded surface modification in order to be used as anode material of lithium-ion battery. This research is about the application of the first and second coating with natural graphite surface modification. By crushing, grinding and sieving, natural graphite became D50 about 17 µm in particle size, which is mixed with phenol resin in different ratio into graphite slurry. Then, it became powder for the first coating by the way of spray-drying. Moreover, the SSA of natural graphite increased after carbonization in high temperature. Finally, the second coating was performed with pitch. The results show that the SSA problem of natural graphite with double coated surface modification was greatly improved. It also lowered the irreversible capacity and enhanced the rate cycle performance of the battery. The better electrochemical performance was exhibited when one coating with 10 wt.% pitch and the double coating via the first coating with 8 wt.% phenol resin without carbonization treatment and the second coating with 10 wt.% pitch. Keywords- Lithium ion battery, Natural graphite, Surface modification, Rate cycle performance