Highly Reversible Zinc‐Air Batteries at −40 °C Enabled by Anion‐Mediated Biomimetic Fat

Abstract The wide application of portable electrical equipment, aerial vehicles, smart robotics, etc. has boosted the development of advanced batteries with safety, high energy density, and environmental adaptability. Inspired by the fat layer on animal bodies, biomimetic fat is constructed as electrolytes of solid‐state zinc‐air batteries to achieve excellent cycling performance at low temperatures. Via tailored anion‐H 2 O interaction, the antifreezing gel electrolytes, with the multi‐performance of interface compatibility, temperature adaptability, and stable power supply simultaneously, build robust Zn|electrolyte interface, thus promoting uniform interfacial electric fields and Zn deposition. Excellent long‐term cyclability of 120 h at a high current density of 50 mA cm −2 are exhibited at 25 °C. Moreover, at −40 °C, a record‐long cycling life of 205 h at a current density as large as 10 mA cm −2 is achieved.