A facile surfactant-assisted self-assembly of LiFePO4/graphene composites with improved rate performance for lithium ion batteries

LiFePO4/graphene composites have been synthesized by a facile surfactant-assisted self-assembly way. In the LiFePO4/graphene composites, graphene could form an effective conductive network for electric transport. The effects of graphene content on structure and electrochemical performance have been investigated. The results show that all LiFePO4/graphene composites have higher rate capability and longer cycling stability than those of primitive LiFePO4. LiFePO4/graphene (with weight ratio of 94:6) displays the lowest charge transfer resistance among all samples and delivers discharge capacity of 132.6 mAh g−1 at 5 C rate, which is much more improved than that of primitive LiFePO4, i.e., 87.5 mAh g−1. Moreover, the capacity retention of all four LiFePO4/graphene composites are about 80% after 1000 cycles, which is much better than that of primitive LiFePO4, i.e., 49%.