Acetylene black-embedded LiMn0.8Fe0.2PO4/C composite as cathode for lithium ion battery

A novel LiMn 0.8 Fe 0.2 PO 4 /C composite is synthesized via a sol–gel process. In this composite, acetylene black is embedded in LiMn 0.8 Fe 0.2 PO 4 . The structure and morphology of the resulting composite are characterized with XRD , SEM, TEM, and BET, and its performance as the cathode of lithium ion battery is investigated by charge–discharge test and EIS , with a comparison of the sample prepared without embedding acetylene black. It is found that the embedded composite exhibits better performance than the non-embedded sample. The former delivers a reversible capacity of 160 mAh g −1 , while the latter only 142 mAh g −1 at 0.1 C (1C = 150 mAh g −1 in the work). The embedded acetylene black not only functions as a barrier for the growing of LiMn 0.8 Fe 0.2 PO 4 particles in the preparation process, which is important for the formation of nano-particles, but also helps build a stable conductive network, thus improving the charge–discharge performance of LiMn 0.8 Fe 0.2 PO 4 .