Ni, Mo Co-doped Lithium Manganate with Significantly Enhanced Discharge Capacity and Cycling Stability

作者：Chen, Meifeng; Chen, Peng; Yang, Fan; Song, Huiyu; Liao, Shijun^*

来源：Electrochimica Acta, 2016, 206: 356-365.

DOI：10.1016/j.electacta.2016.04.148

• Lithium manganate
• solid-state
• co-doping
• lithium-ion batteries
• cycling stability

Ni, Mo co-doped LiMn2O4 cathode materials for lithium-ion batteries were prepared using a high-temperature solid-state method. The materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrochemical impedance spectroscopy. The original material's performance was significantly enhanced by co-doping. The sample with optimal composition, LiNi0.03Mo0.01Mn1.96O4, had a discharge capacity at 1C of 114 mAhg(-1), which was 8.6% higher than that of undoped LiMn2O4. Importantly, this doped material exhibited significantly improved stability: after 300 charge-discharge cycles at 1C, its capacity retention was 91.2%, whereas the capacity retention of the undoped LiMn2O4 was only 61.9% after 300 cycles. SEM images and XRD patterns showed no obvious morphological changes in the co-doped material after cycling, implying that it had high structural stability. We suggest that this material's significantly improved electrochemical performance was probably caused by reduced Mn3+ dissolution and decreased Li+ intercalation and de-intercalation resistances.

• 出版日期2016-7-10
• 单位华南理工大学