Stable charge/discharge of Li at a graphitized carbon fiber electrode in a pure PC electrolyte and the initial charging loss

Highly graphitized carbon is the most widely utilized anode material for Li-ion secondary batteries because of its high reversibility and reliability. However, it has so far been believed that well graphitized carbon material gives no stable Li charge/discharge performance in a pure propylene carbonate (PC)-based electrolyte, since PC decomposes vigorously at the surface of the graphite during the charging process. Surprisingly, we found that a single graphitized carbon fiber revealed a sufficiently stable performance in pure PC containing 1 M LiClO4. The initial irreversible charging capacity not only in PC but in an EC-based electrolyte was found strongly dependent on the conductivity homogeneity of the electrode.