Zinc-ion batteries (ZIBs) are thought to be promising energy sources for versatile and biocompatible units because of their good sustainability and excessive intrinsic security. Nevertheless, their purposes have been hindered by the problems of uncontrolled zinc dendrite development and water-induced aspect reactions in standard liquid electrolytes. Herein, an ionically crosslinked 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 ample purposeful teams of the macromolecules successfully suppress the reactivity of water molecules and facilitate uniform Zn deposition. Furthermore, the composite hydrogel electrolyte reveals 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 secure 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 hydrogel electrolyte additionally confirmed a excessive particular capability of 246.1 mAh g-1 at 0.5 A g-1 and retained 70.7% of its preliminary capability after 150 cycles. The pouch cell labored effectively at totally different bending angles and exhibited a capability retention price of 98% after returning to the preliminary state from 180°-folding. This work goals to assemble high-performance hydrogel electrolytes through the use of low-cost pure supplies, which can present an answer for the appliance of ZIBs in versatile biocompatible units.
