Rate Capabilities of Nanostructured LiMn2 O 4 Electrodes in Aqueous Electrolyte
Rate Capabilities of Nanostructured LiMn2 O 4 Electrodes in Aqueous Electrolyte
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DOI：
10.1149/1.1393483
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发表时间：
2000-06
影响因子：
3.9
通讯作者：
Naichao Li;C. J. Patrissi;G. Che;C. Martin
中科院分区：
文献类型：
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作者：
Naichao Li;C. J. Patrissi;G. Che;C. Martin
采用模板法制备了由LiMn2O4纳米管组成的纳米结构LiMn2O4电极，该纳米管从集流体表面突出，像刷子的刷毛。在LiNO3水溶液电解质中，研究了这些纳米结构电极在4V（vs.Li/Li+）电位平台下的倍率性能.随着形成电极的小管壁厚的减小，速率能力得到提高。这一结果与我们先前对模板合成的电极材料的研究一致，该研究表明，速率能力随着固态Li+传输距离的减小而提高。由最小壁厚的小管制备的电极的倍率性能是非凡的;这些电极可以在高达109 ℃的C倍率下循环。此外，这些研究表明，在该电极/电解质系统的先前研究中观察到的差的循环性能是由充电过程期间水的不希望的氧化引起的。通过控制构成模板合成阴极的纳米管的充电速率和尺寸，可以消除这种不需要的副反应，并且观察到良好的循环寿命。这些数据表明，纳米结构的电极为这种特定的电极/电解质系统提供了独特的优势。
Nanostructured LiMn 2 O 4 electrodes consisting of LiMn 2 O 4 nanotubules that protrude from a current collector surface like the bristles of a brush were prepared using the template method. The rate capabilities of these nanostructured electrodes were investigated at the 4 V (vs. Li/Li + ) potential plateau in aqueous LiNO 3 electrolyte. Rate capability improved with decreasing wall thickness of the tubules which formed the electrode. This result is in agreement with our prior investigations of template-synthesized electrode materials which showed that rate capabilities improve with decreasing distance for Li + transport in the solid state. The rate capabilities of electrodes prepared from the smallest-wall-thickness tubules are extraordinary; these electrodes can be cycled at C rates as high as 109 C. In addition, these investigations suggest that the poor cycling performance observed in prior studies of this electrode/electrolyte system results from unwanted oxidation of water during the charging process. By controlling the charge rate and the dimensions of the nanotubules making up the template-synthesized cathodes, this unwanted side reaction can he eliminated and good cycle life is observed. These data show that the nanostructured electrodes offer a unique advantage to this particular electrode/electrolyte system.