Microstructure and electrochemical performance of LiFePO4 cathode materials modified with binuclear metal aminophthalocyanines

摘要

The monodispersed LiFe1-xMxPO4/C [x approximate to 0.0040; M = Mn2+, Co2+, Ni2+, Cu2+, Zn2+] nanocomposites obtained by LiFePO4 modified with binuclear metal aminophthalocyanines (M-2(PcTa)(2)O and M-2(PcTa)(2)C(CF3)(2)) are utilized as positive electrode materials for lithium ion batteries. The preparation method for these nanocomposites is a controllable solvothermal method using a mixture of ethylene glycol and N,N-dimethylformamide as the solvent. The microstructure and electrochemical properties of the different nanocomposites are discussed and compared. The results show that the LiFePO4 samples modified with M-2(PcTa)(2)C(CF3)(2) can improve the initial discharge specific capacity of the lithium ion battery up to 154.2 mAh.g(-1) at the rate of 0.1 C, and 93.5% of the initial discharge capacity could be retained after 50 cycles. This research shows that the proposed process can enhance the electrochemical performance of high power LiFePO4 for lithium ion batteries.