Breaking Consecutive Hydrogen-Bond Network Toward High-Rate Hydrous Organic Zinc Batteries

摘要

Zinc batteries hold great potential for stationary energy storage but sufferfrom severe dendrite growth, corrosion, and hydrogen evolution troubles inaqueous electrolytes. Despite the impressive efficacy of non-flammablehydrous organic electrolytes in addressing these problems, the insufficientionic conductivity hinders the rate capability and practicability of hydrousorganic Zn batteries. Here, methanol is proposed as a co-solvent for ethyleneglycol (EG)-based hydrous organic electrolytes, where its methyl terminalgroup can interrupt the continuous intermolecular hydrogen bond networkamong EG. The new hydrous organic electrolyte exhibits a doubled ionicconductivity without sacrificing the exceptional nonflammability. As a result,the Zn anode exhibits a long-term cycling stability over 4000 h at0.5 mA cm~(?2), a high Coulombic efficiency of 99.5, high-rate capability up to20 mA cm~(?2), and impressive low-temperature tolerance of ?60 ℃. TheZn‖V_2O_5 pouch cell with the electrolyte is capable of operating under extremeoperation conditions involving needling, package breakage, and evenexposure to fire. This work paves an avenue toward electrolyte design forhigh-rate practical Zn batteries and beyond.