In Situ Polymerization of Ionic Liquid with Tunable Phase Separation for Highly Reversible and Ultralong Cycle Life Zn-Ion Battery
Si Zheng, Licheng Wei, Zhaoyu Zhang, Jiageng Pan, Jiangfeng He, Liang Gao, Cheng Chao Li
Abstract
Severe Zn dendrite growth and side reactions greatly limit the application of aqueous zinc-ion batteries. Herein, we design a layer of polyionic liquid (PCAVImBr) film with a tunable pore size and charge density on the Zn anode to endow homogenized distribution of an electronic field, acerated Zn2+ permeation, and inhabitation of water entry. Such an optimal combination is achieved via a polymerization induced phase separation strategy, where the enhanced cross-linking density arrests the phase separation in a shallow depth and vice versa. Furthermore, the Zn@PCAVImBr electrode has good plating/stripping reversibility, which retains a 99.6% CE efficiency after 3000 cycles. The symmetric cells can achieve a cycle life of more than 2400 h at different current densities. It is worth mentioning that the NVO//Zn@PCAVImBr full cell can still reach a 91.2% capacity retention after nearly 4000 cycles at a high current of 10 A g–1, and provides new insights for the future research of zinc-ion battery anodes.