High Cycle Stability of Nanoporous Si Composites in All-solid-state Lithium-ion Batteries
High Cycle Stability of Nanoporous Si Composites in All-solid-state Lithium-ion Batteries
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DOI：
10.1149/1945-7111/ac81f6
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发表时间：
2022-08-01
影响因子：
3.9
通讯作者：
Takahashi, Masanari
中科院分区：
文献类型：
--
作者：
Okuno, Ryota;Yamamoto, Mari;Takahashi, Masanari
具有大结构起伏的硅的应力松弛是其在锂离子电池（LIB）中的实际应用的关键挑战。在这项研究中，纳米多孔硅颗粒，这是由Mg 2Si还原的介孔二氧化硅球制备的，被施加作为阳极活性材料的全固态锂离子电池（ASSLIBs）与锂3 PS4固体电解质。与低于20%的无孔硅半电池相比，纳米多孔硅半电池表现出优异的循环能力，在50次循环时高容量保持率约为90%。使用电化学阻抗谱和场发射扫描电子显微镜配备能量色散X-射线光谱的纳米多孔和非多孔硅复合阳极的横截面特性进行了准确的比较。基于这些结果，我们得出结论，膨胀/收缩的纳米尺寸的Si孔和弹性变形的Li 3 PS4有效地缓解了结构应力来源于体积变化的Si颗粒/聚集体在锂化和脱锂，从而导致高循环稳定性。这些研究结果为高性能ASSLIB硅基阳极的合理设计提供了有价值的信息。
Stress relaxation of Si with large structural fluctuations is a critical challenge for its practical application in lithium-ion batteries (LIBs). In this study, nanoporous Si particles, which are prepared by Mg2Si reduction of mesoporous SiO2 spheres, are applied as an anode active material for all-solid-state LIBs (ASSLIBs) with a Li3PS4 solid electrolyte. Nanoporous Si half-cells exhibit an excellent cyclability with a high-capacity retention of about 90% at 50 cycles compared to non-porous Si half-cells below 20%. The cross-sectional characteristics of nanoporous and non-porous Si composite anodes are accurately compared using electrochemical impedance spectroscopy and field emission scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy. Based on these results, we conclude that the expansion/contraction of nanosized Si pores and the elastic deformation of Li3PS4 effectively relieve the structural stress derived from the volume change of Si particles/aggregates during lithiation and delithiation, resulting in high cycle stability. These findings provide valuable information for the rational design of Si-based anodes for high-performance ASSLIBs.