Synthesis of Hard Carbon as Anode Material for Lithium Ion Battery

Hard carbon (HC) is a kind of carbon that is difficult to be graphitized and usually is fabricated from pyrolysis of polymers such as phenolic resins, epoxy resins and pitch. From the structural point of view, HC is highly irregular and disordered, and primarily consists of single-layered carbon atoms that are closely and randomly connected. In this work, a sample of HC was synthesized through pyrolysis of oxidized pitch at high temperature (800 degrees C) under nitrogen atmosphere. XRD analysis demonstrated that the HC has higher d-spacing and lower stacking height than graphite. Elemental analysis showed that the synthesized HC have the [H]/[C] atomic ratio of 0.22. Electrochemical tests showed this non-graphitized carbon has higher capacity (600 mAhg(-1)) than the theoretically maximum capacity of 372 mAhg(-1) for C6Li, indicating that the ratio of Li to C atoms is higher than 1/6 and the produced HC is suitable as anode material for Lithium ion battery.