Topological Chitosan Framework Enables Reversible Columnar Array Anodes for High-Performance Aqueous Zinc Batteries
Eco-friendly aqueous zinc batteries (AZBs) are promising alternatives to lead-acid batteries in applications requiring both safety and energy density. However, their practical deployment is hindered by the synergistic deterioration of zinc anodes—structural collapse and kinetic failure—under high depth of discharge (DOD) and high current densities, which severely limits actual energy and power densities. Here, we report a strategy for the in situ integration of a double-layer topological chitosan framework (D-CTS) on current collectors via regulating phase separation kinetics during multistage coordination-neutralization electrophoresis. The vertical through-hole array is formed by coupling instantaneous and delayed phase separation. Subsequently, a columnar zinc array is mediated by D-CTS to construct an integrated component (D-CTS-Zn) comprising a vertical through-hole separator and an array anode. The embedded interconnected nanonetworks within the through-hole walls enable dynamic equilibrium of the columnar zinc array through a lateral ion compensation mechanism. As a result, Zn||Zn symmetric cells with D-CTS-Zn stably cycle over 3000 cycles at 200 mA cm−2 under 60% DOD. The assembled D-CTS-Zn||MnO2 battery delivers an energy density of 83 Wh kg−1 at an ultrahigh power density of 9.25 kW kg−1. This work provides a constructive strategy for chitosan phase separation regulation and separator-induced reversible metal array anodes.