Influence of structure and atom sites on Sn-based anode materials for lithium ion batteries: a first-principle study
Influence of structure and atom sites on Sn-based anode materials for lithium ion batteries: a first-principle study
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DOI：
10.1007/s11434-014-0137-5
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发表时间：
2014-02
影响因子：
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通讯作者：
Zhaowen Huang;She-jun Hu;Xianhua Hou;Qiang Ru;Lingzhi Zhao
中科院分区：
文献类型：
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作者：
Zhaowen Huang;She-jun Hu;Xianhua Hou;Qiang Ru;Lingzhi Zhao
为了了解结构和原子位置对锡基负极材料电化学性能的影响，用第一原理平面波赝势方法研究了锂在SnNi2Cu2和SnNiCu2相中的嵌入-脱嵌机理。计算结果表明，SnNi2Cu2和SnNiCu2都不是锂离子电池的负极材料。锡基阳极的结构与间隙位个数、理论比容量和体积膨胀率有关。不同的原子位置导致间隙位置的不同作用力，从而导致形成能、态密度和杂化轨道类型的不同。为了验证计算模型的正确性，采用化学还原-共沉积法制备了SnNi2Cu合金负极材料。实验结果证明了理论设计的合理性。因此，在选择锡基合金阳极时，应注意最大限度地增加间隙位个数，合理分布原子，使这些位点处的作用力降到最低，有利于锂离子的嵌入和脱嵌。
To understand the influence of structure and atom sites on the electrochemical properties of Sn-based anode materials, the lithium intercalation–deintercalation mechanisms into SnNi2Cu and SnNiCu2phases were studied using the first-principle plane wave pseudo-potential method. Calculation results showed that both SnNi2Cu and SnNiCu2were unsuitable anode materials for lithium ion batteries. The Sn-based anode structure related to the number of interstitial sites, theoretical specific capacity, and volume expansion ratio. Different atom sites led to different forces at interstitial sites, resulting in variations in formation energy, density of states, and hybrid orbital types. In order to validate the calculated model, the SnNi2Cu alloy anode material was synthesized through a chemical reduction-codeposition approach. Experimental results proved that the theoretical design was reasonable. Consequently, when selecting Sn-based alloy anodes, attention should be paid to maximizing the number of interstitial sites and distributing atoms reasonably to minimize forces at these sites and facilitate the intercalation and deintercalation of lithium ion.