Alloy anodes hold promise for enabling high-energy solid-state batteries, but their substantial volume changes during charge/discharge can cause structural and mechanical degradation within the all-solid-state environment. It is therefore critical to understand how material evolution and mechanical stress within alloy-anode-based solid-state batteries are related. Here, we investigate stress (stack pressure) evolution within batteries with composite anodes that contain active materials such as silicon, tin, and antimony, along with an argyrodite-type electrolyte and LiNi_0.33Mn_0.33Co_0.33O₂ cathodes. We measure megapascal-level stress changes that are dependent on the amount of lithium transferred, and we find that stress signatures and hysteresis during charge/discharge are affected by the electrode structure and the active material. We furthermore show that these composite-alloy anodes enable stable long-term cycling with associated cyclic-stress changes. These findings provide new understanding of the relationship between electrochemistry and mechanics within solid-state batteries, which is important because megapascal-level stack pressures are generally necessary for optimal performance.

合金阳极有望实现高能固态电池，但它们在充电/放电过程中的显着体积变化会导致全固态环境中的结构和机械退化。因此，了解合金阳极固态电池中的材料演变和机械应力之间的关系至关重要。在这里，我们研究了具有复合负极的电池内的应力（堆压）演变，该负极包含硅、锡和锑等活性材料，以及银铅矿型电解质和 LiNi _0.33 Mn _0.33 Co _0.33 O ₂阴极。我们测量了依赖于锂转移量的兆帕级应力变化，我们发现充电/放电过程中的应力特征和滞后受电极结构和活性材料的影响。我们进一步表明，这些复合合金阳极能够实现稳定的长期循环，并伴随着相关的循环应力变化。这些发现为固态电池中电化学和力学之间的关系提供了新的理解，这很重要，因为兆帕级的堆栈压力通常是最佳性能所必需的。