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Complementary characterization results show that chemical dissolution of transition metal in LiMn₂O₄is caused by solvolysis-generated HF, which can be suppresed by rational design of a group of nonsolvolytic electrolytes. 

Solid-state electrolytes (SSEs) are challenged by complex interfacial chemistry and poor ion transport through the interfaces they form with battery electrodes. Here, we investigate a class of SSE composed of micrometer-sized lithium oxide (Li₂O) particles dispersed in a polymerizable 1,3-dioxolane (DOL) liquid. Ring-opening polymerization (ROP) of the DOL by Lewis acid salts inside a battery cell produces polymer-inorganic hybrid electrolytes with gradient properties on both the particle and battery cell length scales. These electrolytes sustain stable charge-discharge behavior in Li||NCM811 and anode-free Cu||NCM811 electrochemical cells. On the particle length scale, Li₂O retards ROP, facilitating efficient ion transport in a fluid-like region near the particle surface. On battery cell length scales, gravity-assisted settling creates physical and electrochemical gradients in the hybrid electrolytes. By means of electrochemical and spectroscopic analyses, we find that Li₂O particles participate in a reversible redox reaction that increases the effective CE in anode-free cells to values approaching 100%, enhancing battery cycle life. 

Rechargeable metal–air batteries operated in ambient air fail as a result of complex anode surface reactions. Interphases composed of metallic In protect Li anodes, enabling Li–air batteries to operate in ambient air. 

We report a purely mechanical “cold-compression flow” method for fabricating Zn, Sn, and In substrates with tunable crystallographic textures. Using textured Zn as a model system, we investigate Zn electrocrystallization and demonstrate correlated growth of crystalline films with correlation lengths from tens to hundreds of micrometers. At 5 milliamperes per square centimeter (mA/cm²), capacities between 20 and 82 milliampere hours per square centimeter (mA·hour/cm²) are achieved depending on substrate texture level. At higher currents (40 mA/cm²), capacities reach up to 604 mA·hour/cm². Rotating disk electrode studies show that dominantly (002) textured Zn substrates exhibit enhanced corrosion resistance and reduced interphase passivation. We introduce an effective Damköhler number (Da*) to concisely describe morphological evolution during electrocrystallization across substrates with different textures. High-texture (002) Zn substrates substantially enhance performance in high-capacity (~20 mA·hour/cm²) symmetric Zn||Zn cells and full cells (Zn||δ-MnO₂and Zn||I₂), enabling fast-charging and prolonged energy storage in coin and pouch rechargeable Zn battery formats.