Improving Low-Pressure Performance of Silicon Anodes in All-Solid-State Batteries using Ag

All-solid-state batteries (ASSBs) have emerged as promising alternatives to conventional lithium-ion batteries (LIBs), offering enhanced safety and superior energy density. Similarly to LIBs, Si stands out as an attractive anode candidate for ASSBs, owing to its high theoretical capacity (3580 mA h g^-1) and low voltage (&lt;0.4 V vs. Li/Li⁺). However, it has been well documented that Si faces a significant challenge in LIBs; its immense volume change (&gt;300%) during charge-discharge cycles leads to substantial pulverization and consequent electrical isolation of Si particles. In LIBs, this issue is often mitigated by combining Si with nanostructured carbonaceous materials, such as carbon nanotubes and graphene. Yet, in ASSBs, these same additives can consume Li⁺ sources and generate byproducts that exhibit poor Li⁺ conductivity. Recent advancements have demonstrated notable performance improvements in Si-based ASSBs by excluding SEs and carbon additives, albeit with minimal binder content and operation at 50 MPa. Nevertheless, from practical application, it is critical to evaluate and ensure performance sustainability at substantially reduced operating pressures.<br/>Herein, we provide a comparative analysis of the performance of Si ASSBs at varying operating pressures, emphasizing the significance of assessments at low pressures. We also introduce our approach to enhancing low-pressure performance through interfacial modification using metallic Ag. Lastly, we offer a series of complementary analytical results that delve into the underlying mechanism contributing to performance enhancement.<br/><br/>[1] Lee, Y.G., et al. Nat. Energy 2020, 5, 299–308.<br/>[2] Lim, H., et al. Energy Storage Mater. 2022, 50, 543.