Lithionic Applications of Garnet Solid Electrolytes Enhanced by Surface Micropatterning

Garnet-type solid electrolytes are promising for lithionic devices such as solid-state batteries and memristors, yet the native surface defects at the lithium/garnet interface cause uncontrollable current and stress concentrations that lead to premature device failure. Here, we employ a laser-micropatterning strategy to modulate the local current and stress fields, transforming interfacial dynamics from an uncontrollable defect-governed process into a microstructure-dictated tunable response. Specifically, smooth U-grooved structures homogenize current distribution and promote lithium creep, suppressing defect-driven interfacial degradation and enabling a symmetric lithium cell to be stably cycled at 0.3 mA cm −2 for over 4000 h; sharp cone-shaped hole arrays create well-defined electrochemical hotspots that localize reversible filament formation and dissolution, yielding a lithium-based memristor with robust switching reproducibility over 300 cycles. This microstructure-oriented field-modulation strategy paves the way for high-performance lithionic applications and offers a general approach to engineering interfacial stability and functionality in solid-state ionic systems.