Electrochemical Performance of Needle Coke and Pitch Coke Used as Anode Material for Li-ion Battery

Graphitized cokes were prepared from needle coke and pitch coke to be used as anode material for Li-ion battery.Effect of the physical chemistry of the two cokes on the microstructure and electrochemical properties of their graphitized samples were investigated.The results indicate that needle coke was easier to be graphitized than pitch coke,because it was derived from purified mesophase pitch.When needle coke was graphitized at 2800℃,the values of d_002,La,Lc were 0.3373nm,56.05nm,27.11nm,respectively,while the La,Lc value of graphitized pitch coke was 53.4% of that of graphitized needle coke.The Li~+ extraction capacitance of graphitized needle coke could maintain at 301mAh/g after it was charge/discharged for 40 cycles,while it was only 240mAh/g for graphitized pitch coke.