In brittle solid electrolytes, nanoscale defects (particularly nano-cracks) form easily during processing and handling due to the brittle nature of oxide ceramics, even for high density samples. Specifically, surface cracks can easily result from polishing, uneven applied stack pressure, and impacts. The predominant mitigation strategies have focused on decreasing the local current density during operation through methods such as interlayers and structural modifications. In particular, metallic coatings are effective for regulating Li electroplating in solid-state batteries. Mechanistically, it is believed that metallic coatings improve the contact and wetting of Li metal . Among various metals, metallic silver has stood out for enabling fast and uniform Li electroplating owing to good wettability and decreasing the Li nucleation energy when applied as a coating on solid electrolytes. Alternatively, methods to enhance material strength and toughness have received recent attention. Residual compressive stress at the surface of solid electrolytes was predicted to prevent Li intrusion . One route to generate such residual compressive stress is physical ion implantation , though this method potentially generates a resistive surface layer that hinders Li ion transport. Thus, there is a critical need to identify a model material system with engineerable compressive stress and to establish a platform for dynamically observing Li intrusion. Among potential routes to generate compressive stress, surface doping is an attractive path. In particular, silver ions exhibit high polarizability and possess a large ionic radius compared to that of lithium ions, suggesting that they may induce significant residual stress when doped into host materials. Such Ag-Li ion exchange has been extensively investigated in many Li containing oxides for optical waveguides and glass-ceramics, using either a molten salt method or a Ag metal electrode . One challenge in this context is the decoupling of the effect of metallic Ag (which improves wetting and enhances electronic contact) from that of Ag-Li ion exchange.