Metal tetrabromophthalocyanines mediate the structure and electrochemical performance of lithium iron phosphate as cathode materials for lithium-ion batteries

• LiFePO4 was modified by metal tetrabromophthalocyanine for the first time.
• The composites were prepared by solvothermal followed by calcination method.
• The composites were evaluated as cathodes for Li ion batteries.
• All of the composites deliver highly improved performance.

A novel series of cathode materials based on lithium iron phosphate (LiFePO4) for Li-ion batteries are synthesized by comprehensive utilization of solvothermal technique and high temperature calcination method. In this work, metal tetrabromophthalocyanines are utilized to control the structure of LiFePO4 and the electrochemistry of the final products is studied. The composition, structure and morphology characterizations include ICP-AES, XRD, SEM and TEM experiments. Electrochemical performance of each modified material in the Li-ion battery is evaluated by electrochemical measuring technology. The results exhibit that the as-synthesized samples can improve the initial discharge capacity of the Li-ion battery up to 150.7 mAh g− 1 at the rate of 0.1 C. In addition, the most excellent composite can enhance the rate capability of the battery dramatically compared with that of the pristine LiFePO4.