Enhanced electrochemical stability of Al-doped LiMn2O4 synthesized by a polymer-pyrolysis method
Enhanced electrochemical stability of Al-doped LiMn2O4 synthesized by a polymer-pyrolysis method
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DOI：
10.1016/j.electacta.2008.07.037
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发表时间：
2008-12
影响因子：
6.6
通讯作者：
Lifen Xiao;Yanqiang Zhao;Yanyan Yang;Yuliang Cao;X. Ai;Hanxi Yang
中科院分区：
文献类型：
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作者：
Lifen Xiao;Yanqiang Zhao;Yanyan Yang;Yuliang Cao;X. Ai;Hanxi Yang
采用聚合物热解法合成了LiAlxMn 2 − xO 4（x=0，0.02，0.05，0.08）样品。采用X射线衍射和扫描电镜研究了LiAlxMn 2 − xO 4样品在800°C下煅烧6 h后的结构和形貌。结果表明，所有样品均具有较高的结晶度，八面体形貌规则，粒径均匀，在100- 300 nm之间。采用恒流充放电和循环伏安法测试了其电化学性能。结果表明，Al掺杂的LiMn 2 O 4在55°C高温下循环性能良好，容量没有严重下降。特别地，LiAl0.08Mn1.92O4样品在55°C下50次循环后表现出99.3%的优异容量保持率，证实了通过少量Al掺杂大大增强的LiMn 2 O 4的电化学稳定性。
LiAlxMn2−xO4samples (x=0, 0.02, 0.05, 0.08) were synthesized by a polymer-pyrolysis method. The structure and morphology of the LiAlxMn2−xO4samples calcined at 800°C for 6h were investigated by powder X-ray diffraction and scanning electron microscopy. The results show that all samples have high crystallinity, regular octahedral morphology and uniform particle size of 100–300nm. The electrochemical performances were tested by galvanostatic charge–discharge and cyclic voltammetry. The results demonstrate that the Al-doped LiMn2O4can be very well cycled at an elevated temperature of 55°C without severe capacity degradation. In particular, the LiAl0.08Mn1.92O4sample demonstrates excellent capacity retention of 99.3% after 50 cycles at 55°C, confirming the greatly enhanced electrochemical stability of LiMn2O4by a small quantity of Al-doping.