Regulating Liquid‐Phase Mass Transport via Electric Field‐Pore Size Synergy in Separator for Long‐Life Zinc‐Ion Batteries

ABSTRACT

The separator critically dictates liquid‐phase mass transport in aqueous zinc‐ion batteries (AZIBs), while it is poorly regulated in conventional commercial separators due to inappropriate pore structure and heterogeneous surface charge. Herein, we engineer a multifunctional separator (PTT‐GF‐D) that integrates ordered nanoporous channels with highly negatively charged surface to synchronously regulate ion flux and interfacial electric fields. This design effectively optimizes liquid‐phase mass transport, thereby promoting homogeneous multi‐site nucleation, accelerating Zn ²⁺ desolvation, and mitigating Zn ²⁺ concentration polarization. Consequently, the symmetric cells achieve exceptional reversibility, stably operating for 3300 h under 1 mA cm ⁻² , 1 mAh cm ⁻² and maintaining robust stability over 1000 h even under harsh conditions of 10 mA cm ⁻² , 10 mAh cm ⁻² . The as‐fabricated Zn||MnO ₂ full cell delivers a specific capacity of 130 mAh g ⁻¹ at 1 A g ⁻¹ , preserving 96.2% of its initial capacity after 1000 cycles. A large‐sized pouch cell is also demonstrated, which can operate at 5 mA cm ⁻² for 100 cycles without noticeable decay. This study establishes the critical synergy of pore architecture and surface charge engineering in separators to control liquid‐phase mass transport, offering a promising strategy for developing high‐performance and practical AZIBs.