摘要
LiNi0.85CO0.15-xAlxO2 samples （x=0.025, 0.05 and 0.10） were prepared by solid state reaction at 725℃ for 24 h from LiOH-H2O, Ni2O3, Co2O3 and Al（OH）3 under oxygen flow. Layered LiNiO2 simultaneously doped by Co-Al has been tried to improve the cathode performance. The results showed that substitution of optimum amount Al and Co for the Ni in LiNiO2 definitely had some beneficial effect on increasing the capacity and cycling behavior. When increasing x in LiNio.85CO0.15-xAlxO2, the initial discharge capacity decreased and its cyclability increased. Compromising high specific capacity and good cyclability, the optimum x in LiNi0.85Co0.15-xAlxO2 was x=0.05. As a consequence, LiNi0.85Co0.15-xAlxO2 had the first discharge capacity of 186.2 mAh/g and a capacity of 180.1 mAh/g after 10 cycles. Differential capacity vs voltage curves indicated that the co-doped LiNiO2 showed suppression of the phase transitions as compared with LiNiO2.
LiNi0.85CO0.15-xAlxO2 samples （x=0.025, 0.05 and 0.10） were prepared by solid state reaction at 725℃ for 24 h from LiOH-H2O, Ni2O3, Co2O3 and Al（OH）3 under oxygen flow. Layered LiNiO2 simultaneously doped by Co-Al has been tried to improve the cathode performance. The results showed that substitution of optimum amount Al and Co for the Ni in LiNiO2 definitely had some beneficial effect on increasing the capacity and cycling behavior. When increasing x in LiNio.85CO0.15-xAlxO2, the initial discharge capacity decreased and its cyclability increased. Compromising high specific capacity and good cyclability, the optimum x in LiNi0.85Co0.15-xAlxO2 was x=0.05. As a consequence, LiNi0.85Co0.15-xAlxO2 had the first discharge capacity of 186.2 mAh/g and a capacity of 180.1 mAh/g after 10 cycles. Differential capacity vs voltage curves indicated that the co-doped LiNiO2 showed suppression of the phase transitions as compared with LiNiO2.
基金
This work was supported by the National Natural Science Foundation of China （No. 29833090）.
