Huo, HanyuHanyuHuoJiang, MingMingJiangBai, YangYangBaiAhmed, ShamailShamailAhmedVolz, KerstinKerstinVolzHartmann, HannahHannahHartmannHenss, AnjaAnjaHenssSingh, Chandra VeerChandra VeerSinghRaabe, DierkDierkRaabeJanek, JürgenJürgenJanek2024-12-112024-12-112024https://jlupub.ub.uni-giessen.de/handle/jlupub/20023https://doi.org/10.22029/jlupub-19378Silicon is a promising anode material due to its high theoretical specific capacity, low lithiation potential and low lithium dendrite risk. Yet, the electrochemical performance of silicon anodes in solid-state batteries is still poor (for example, low actual specific capacity and fast capacity decay), hindering practical applications. Here the chemo-mechanical failure mechanisms of composite Si/Li6PS5Cl and solid-electrolyte-free silicon anodes are revealed by combining structural and chemical characterizations with theoretical simulations. The growth of the solid electrolyte interphase at the Si|Li6PS5Cl interface causes severe resistance increase in composite anodes, explaining their fast capacity decay. Solid-electrolyte-free silicon anodes show sufficient ionic and electronic conductivities, enabling a high specific capacity. However, microscale void formation during delithiation causes larger mechanical stress at the two-dimensional interfaces of these anodes than in composite anodes. Understanding these chemo-mechanical failure mechanisms of different anode architectures and the role of interphase formation helps to provide guidelines for the design of improved electrode materials.enNamensnennung 4.0 Internationalddc:540