The effect of graphene wrapping on the performance of LiFePO4 for a lithium ion battery

Graphene wrapping is used to experimentally understand how a carbon coating works in improving the electrochemical performance of the LiFePO4 cathode for a lithium ion battery. A full wrapping of LiFePO4 by graphene is realized by a self-assembly driven by the electrostatic interaction in a graphene oxide suspension. Results indicate that a partial graphene wrapping provides a balance between increased electron transport and fast ion diffusion while full graphene wrapping isolates LiFePO4 from the electrolyte and retards ion diffusion. This indicates that steric hindrance for ion diffusion should be considered together with electron transport in constructing a carbon coating layer. (C) 2013 Elsevier Ltd. All rights reserved.