二元共聚物热解碳包覆的石墨负极材料

Abstract

以苯萘二元共聚物包覆天然石墨后进行热处理,用所制备的包覆石墨作为锂离子电池的负极材料,与包覆前石墨材料相比较,可逆容量提高了10%,不可逆容量降低了7%,循环性能也得到了大的改善.X射线分析表明,改性后该石墨晶体中三方石墨的含量增高.

Carbon-coated natural graphite has been prepared by mixing graphite particles with benzene-naphthalene copolymer and thermaly treating the mixture under a nitrogen gas flow. The coated natural graphite showed about 10% higher reversible capacity and about 7% lower irreversible capacity as an anode material for lithium ion battery with pristine graphite. The cycling behavior of graphite was also improved after being coated. The X-ray diffraction (XRD) results showed that the rhombohedral phase fraction of natural graphite increased after being coated.