论文标题
NI-SN金属层作为锂离子电池中SI阳极的有效缓冲矩阵
Ni-Sn intermetallics as efficient buffering matrix of Si anodes in Li-ion batteries
论文作者
论文摘要
为了成功地整合硅在锂离子电池的阳极中，应最大程度地减少其内在的循环能力衰减。在这项工作中，在基于SI的阳极可逆静电片期间，研究了NI-SN的金属间代理作为缓冲矩阵。 Si/Ni-SN复合材料已通过使用C和AL作为过程控制剂的机械铣削合成。 NI3SN4，NI3SN2金属及其双重混合物用作缓冲矩阵的组成部分。复合材料的结构，组成和形态已经通过X射线衍射（XRD），119SN传输Mössbauer光谱（TMS）和扫描电子显微镜（SEM）分析。它们由嵌入多相基质中的〜150 nm si纳米颗粒组成，其纳米结构化可以改善增加Ni3sn4量。通过半细胞中的电静态循环分析了复合材料的电化学性能。对于双重矩阵Ni3sn4-Ni3SN2，发现NI3SN4具有电化学活性，而NI3SN2无活性，则发现了实用应用的最佳结果。低容量损失，0.04％/循环和高库仑效率为99.6％，在200个周期中获得了高于500 mAh/g的高可逆容量，以中等状态C/5
For a successful integration of silicon in high-capacity anodes of Li-ion batteries, its intrinsic capacity decay on cycling due to severe volume swelling should be minimized. In this work, Ni-Sn intermetallics are studied as buffering matrix during reversible lithiation of Si-based anodes. Si/Ni-Sn composites have been synthetized by mechanical milling using C and Al as process control agents. Ni3Sn4, Ni3Sn2 intermetallics and their bi-phasic mixture were used as constituents of the buffering matrix. The structure, composition and morphology of the composites have been analyzed by X-ray diffraction (XRD), 119Sn Transmission Mössbauer Spectroscopy (TMS) and scanning electron microscopy (SEM). They consist of ~ 150 nm Si nanoparticles embedded in a multi-phase matrix, the nanostructuration of which improves on increasing the Ni3Sn4 amount. The electrochemical properties of the composites were analyzed by galvanostatic cycling in half-cells. Best results for practical applications are found for the bi-phasic matrix Ni3Sn4-Ni3Sn2 in which Ni3Sn4 is electrochemically active while Ni3Sn2 is inactive. Low capacity loss, 0.04 %/cycle, and high coulombic efficiency, 99.6%, were obtained over 200 cycles while maintaining a high reversible capacity above 500 mAh/g at moderate regime C/5
