Phase Inversion‐Induced Porous Polymer Coating for High Rate and Stable Zinc Anode

Abstract Polymer coatings are emerged as promising candidates for zinc anode artificial solid electrolyte interphase (ASEI) owing to their barrier effect and zincophilicity. However, the poor ionic conductivity of conventional polymer coatings limits their application. Herein, inspired by epidermis function, a porous poly(methylmethacrylate) (PMMA) coating is fabricated to stabilize Zn anode via a novel phase inversion method. The modified Zn anode delivers a remarkable lifespan of over 4000 h at 1 mA cm −2 , 1 mAh cm −2 , and 120 h at 20 mA cm −2 , 20 mAh cm −2 in symmetrical cells. Moreover, porous PMMA‐Zn||NVO full cell also exhibits an excellent cycling stability over 500 cycles at 1 A g −1 as well as an ultralong lifespan exceeding 5000 cycles at 5 A g −1 . The excellent cycling stability and rate performance are mainly attributed to the avoided side reactions by the coating protection, as well as the enhanced diffusion and reaction kinetics derived from the good zincophilicity and porous structure of porous PMMA. The facile and universal method for fabricating porous polymer ASEI provides a new insight for the application of conventional polymer materials in Zn anode protection.