Zinc-ion batteries (ZIBs) are considered promising energy sources for versatile and biocompatible units as a consequence of their good sustainability and excessive intrinsic security. Nonetheless, their purposes have been hindered by the problems of uncontrolled Zn dendrite development and extreme water-induced facet reactions in standard liquid electrolytes. Herein, an ionically cross-linked composite hydrogel electrolyte based mostly on pure biomacromolecules, together with iota-carrageenan and sodium alginate, is designed to advertise extremely environment friendly and reversible Zn plating/stripping. The considerable purposeful teams of macromolecules successfully suppress the reactivity of water molecules and facilitate uniform Zn deposition. Furthermore, the composite hydrogel electrolyte displays a excessive ionic conductivity of 5.89 × 10−2 S cm−1 and a Zn2+ transference variety of 0.58. Consequently, the Zn‖Zn symmetric cell with the composite hydrogel electrolyte exhibits a steady cycle lifetime of greater than 500 h. In the meantime, the Zn‖NH4V4O10 coin cell with the composite hydrogel electrolyte retains a excessive particular capability of roughly 200 mA h g−1 after 600 cycles at 2 A g−1. The Zn‖NVO pouch cell based mostly on the composite hydrogel electrolyte additionally exhibits a excessive particular capability of 246.1 mA h g−1 at 0.5 A g−1 and retains 70.7% of its preliminary capability after 150 cycles. The pouch cell performs properly at totally different bending angles and displays a capability retention price of 98% after returning to its preliminary state from 180° folding. This work goals to assemble high-performance hydrogel electrolytes utilizing low-cost pure supplies, which can present an answer for the appliance of ZIBs in versatile biocompatible units.
