STRUCTURAL AND ELECTROCHEMICAL CHARACTERISTICS OF GRAPHITIZED MCMB COATED WITH PYROCARBON USING PRESSURE-PULSED CHEMICAL VAPOR DEPOSITION TECHNIQUE

摘要

Several sorts of carbon-coating techniques have attracted more attention in recent years as a promising methods to improve the performance of active materials for rechargeable lithium-ion batteries [1,2]. Pyrocarbon-coating by chemical vapor deposition (CVD) is one of the effective methods for surface-modifying of graphite-based anodes to improve the anode performance, especially in propylene carbonate (PC) — based solvent [3]. However, it is difficult for conventional CVD to achieve the homogeneous deposition of pyrocarbon having the relatively high crystallinity. In this laboratory, we have used pressure-pulsed chemical vapor deposition / infiltration (pulse-CVD/CVT) technique to prepare or modify negative electrode materials for lithium-ion batteries [4-6]. In this study, pulse-CVD process was adopted to modify the surface structure of graphitized Mesocarbon Microbeads (MCMB) anode material to improve its electrochemical properties in PC containing electrolytes.