Due to the increasing demands for the high capacity lithium ion batteries (LIBs) for use in mobile devices and electric vehicles, a new anode material with a higher capacity than that of graphite (372 mAh/g) is desired. As a candidate of such anode material, alloy-type anode (Si, Ge, Sn, etc.) shows much higher capacity than that of graphite [1]. However, their large volume modification during the charge-discharge process limits their cyclic performances. On the other hand, high capacity carbon based materials, such as graphene sheets, carbon nanotubes and nanofibers have also attracted much attention [1]. For practical use, their high intercalation potential of lithium and the difficulty of mass-production of these materials have to be overcome.

In this study, we report a new type of high capacity carbon based material, Ca_0.6-xB_1.2C_4.8. It is a novel material obtained by one-pot heat-treatment of graphite with boron and calcium sources. Its highly ordered graphite-like layer structure distinguishes it from the former reported high capacity carbon based materials, such as graphene sheets, carbon nanotubes and nanofibers. Its specific capacity was 552 mAh/g, which is much higher than that of graphite. This result suggests the possibility of realizing a yet higher capacities for graphite based materials. The detailed preparation method, characterization, and electrochemical measurements will be discussed on the session.

References

[1] Goriparti et al., J. Power Sources, 257, 421-443 (2014)