Homogeneous low-tortuosity membrane with fast ion transfer towards life-durable low-temperature zinc metal batteries

Aqueous zinc metal batteries (AZMBs) have attracted significant attentions in the energy storage field due to their environmental safety. However, sluggish reaction kinetics of Zn(H2O)(6)(2+) desolvation and corresponding Zn2+ ion transfer hinder the low-temperature performance of AZMBs. Herein, the boundary inhibition effect of ion-related pathway is initially uncovered, and a homogeneous low-tortuosity separator membrane (LTSM) with enhanced kinetics of ion desolvation and transfer is proposed. This low-tortuosity structure of LTSM significantly enhances the effectiveness of pore sieving effect toward large Zn(H2O)(6)(2+) clusters, minimizing ion transfer barriers and homogenizing ion flux, as revealed by Raman and sum frequency generation spectroscopies. Encouragingly, the metallic Zn with LTSM exhibits lower nucleation overpotentials of similar to 50 mV, showcasing an ultralong lifespan of over 10,000 h at 0 degrees C. Even under -10 degrees C, a cycle life up to 5000 h is also achieved. The as-prepared full cells assembled with LTSM display the specific capacity of 200 mAh g(-1) after 4000 cycles at 8 A g(-1) under 0 degrees C. Increasing to 6.3 mg cm(-2), the large areal pouch cell stabilizes for 160 cycles with retained capacity of 315 mAh g(-1), demonstrating feasibility of eliminating the boundary inhibition effect with low-tortuosity separator membrane for practical applications.