Ni, Mo Co-doped Lithium Manganate with Significantly Enhanced Discharge Capacity and Cycling Stability
Ni, Mo Co-doped Lithium Manganate with Significantly Enhanced Discharge Capacity and Cycling Stability
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Ni、Mo共掺杂锰酸锂显着增强放电容量和循环稳定性
DOI：
10.1016/j.electacta.2016.04.148
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发表时间：
2016-07-10
影响因子：
6.6
通讯作者：
Liao, Shijun
中科院分区：
文献类型：
--
作者：
Chen, Meifeng;Chen, Peng;Liao, Shijun
采用高温固相法制备了Ni、Mo共掺杂的锂离子电池正极材料LiMn 2 O 4。采用X射线衍射（XRD）、扫描电子显微镜（SEM）和电化学阻抗谱对材料进行了表征。通过共掺杂，原始材料的性能显著增强。最佳组成的样品LiNi0.03Mo0.01Mn1.96O4在1C下的放电容量为114 mAhg（-1），比未掺杂的LiMn 2 O 4提高了8.6%。重要的是，这种掺杂的材料表现出显著改善的稳定性：在1C下300次充放电循环后，其容量保持率为91.2%，而未掺杂的LiMn 2 O 4在300次循环后的容量保持率仅为61.9%。SEM和XRD分析表明，共掺杂材料在循环后没有明显的形貌变化，具有较高的结构稳定性。我们认为，这种材料的显着改善的电化学性能可能是由于减少Mn 3+的溶解和降低Li+的嵌入和脱嵌电阻。(c)2016爱思唯尔有限公司版权所有
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. (c) 2016 Elsevier Ltd. All rights reserved.