Toward reversible wide-temperature Zn storage by regulating the electrolyte solvation structure via trimethyl phosphate

The wide-scale application of zinc-ion batteries (ZIBs) is largely restricted by dendrite formation, hydrogen evolution corrosion and capacity fading, caused by the coordinated H2O within the Zn2+-solvation shell as well as reactive active water in the bulk electrolyte. Here, one green and flame-retardant additive, trimethyl phosphate (TMP) is introduced into aqueous electrolyte systems, contributing to Zn2+-solvation shell reshaping and promoting the stability hydrogen bonding network of H2O. The strategy is significant in suppressing water-induced side reactions and dendrite growth, enabling an ultralong cycling lifespan of 7000 h at 1 mA·cm−2 and 0.5 mAh·cm−2 in Zn symmetrical cell. In addition, Zn|VO2(B) full cells with TMP addition exhibit an ultralong cyclic performance for 1200 cycles at 1 A·g−1 with 97.86% capacity retention even at 0 °C, which contributes to taking a step closer to commercial application. This work demonstrates the feasibility of developing electrolytes for practical ZIBs that integrate safety, sustainability and wide-temperature applications.