Impact of the Cut-Off Voltage on Cyclability and Passive Interphase of Sn-Polyacrylate Composite Electrodes for Sodium-Ion Batteries
Impact of the Cut-Off Voltage on Cyclability and Passive Interphase of Sn-Polyacrylate Composite Electrodes for Sodium-Ion Batteries
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DOI：
10.1021/acs.jpcc.6b03459
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发表时间：
2016-07
影响因子：
3.7
通讯作者：
Mika Fukunishi;N. Yabuuchi;M. Dahbi;J. Son;Yi-Tao Cui;H. Oji;S. Komaba
中科院分区：
文献类型：
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作者：
Mika Fukunishi;N. Yabuuchi;M. Dahbi;J. Son;Yi-Tao Cui;H. Oji;S. Komaba
在非水钠电池中，研究了由锡粉、石墨和聚丙烯酸钠组成的锡基电极在0.65和0.70 V的不同截止电压下电化学钠化的可逆性。截止电压上限是提高电化学可逆性的关键因素之一。当截止电压为0.70 V时，钠化/去钠化循环性能不稳定，并伴有容量衰减，表明纯Sn金属催化的Sn颗粒在0.68 V和0.40 V时，钝化层的阳极分解分别导致溶解和再形成。反复溶解和重组带来了更厚的和电阻性的表面层，从电解质分解产物的积累，这是澄清的X射线光电子能谱。相反，通过简单地将上限截止电压改变为0.65 V，由于排除了在0.
Reversibility of electrochemical sodiation for Sn-based electrodes consisting of Sn powder, graphite, and sodium polyacrylate was examined at different upper cutoff voltages of 0.65 and 0.70 V in nonaqueous Na cells. The upper cutoff voltage is one of the key factors to improve the electrochemical reversibility. In case of a cutoff voltage of 0.70 V, the sodiation/desodiation cycle performance was not stable and accompanied by capacity decay, indicating that the anodic decomposition of passivation layer is led to the dissolution and reformation at 0.68 and 0.40 V, respectively, on Sn particles that were catalyzed by pure Sn metal. The repeated dissolution and reformation brought a thicker and resistive surface layer, resulting from the accumulation of electrolyte decomposition products, which was clarified by X-ray photoelectron spectroscopy. In contrast, the capacity retention and stability were improved by simply changing the upper cutoff voltage to 0.65 V due to exclusion of the SEI decomposition at 0....