Study On The Synthesis And Properties Of LiFePO₄ With Ferric Ions

Nowadays, with the problem of energy come to be a big question, as one kind of the most promising cathode material,the olivine LiFePO4 has got much attention for the advantages as follow:abundant raw material, low cost, little environment pollution, high energy density and stable cycle performance. But it has low electronic conductivity and lithium ion diffusivity which will be a huge problem to limit its development. In this paper, the cathode materials was synthesized by two-step reaction with Fe(NO3)3, Li2CO3, (NH4)2HPO4, C12H22O11,etc. The materials'synthesis factors,surface morphology, structure and electrochemical performance were studied through XRD, SEM, and charge-discharge tests.The effects of the solution s consistency, pH value and stir time on FePO4 and cathode materials physical properties and electrochemical performance were investigated. The results indicated that materials prepared under consistency as 0.1mol/L and pH value as 2.0 and stir time as 6h has better surface morphology and electrochemical performance.Cathode materials was prepared with Cu2+ as dopant, and the results indicated that specific capacity first charge-discharge come to 140mAh/g with Cu2+take 2 wt%percent, and the cycle performance will be good, too.