Application Of Polyzwitterion Hydrogel In Quasi-Solid State Zinc Metal Battery

To meet people’s needs for large-scale energy storage and the safety and economics of wearable devices,compared with the organic electrolyte system of lithium ion batteries,aqueous zinc metal batteries with higher economical and safety of the electrolyte systems,is considered to be an ideal battery system.However,the side reactions and interface corrosion of zinc metal anodes and aqueous electrolytes and the growth of dendrites can cause a series of problems such as irreversible loss of battery capacity and poor electrochemical cycling performance,which limit the industrialized application of aqueous zinc batteries.As a consequence,require modification is required for zinc metal batteries.Modification of zinc metal batteries is a systematic project,including optimization of electrolyte system,modification of zinc metal anode interface,and design of composite anode.Towards the optimization of the electrolyte system,including the replacement of the aqueous electrolyte system with hydrogel system,the side reactions and other interface issues between the aqueous electrolyte and the zinc metal anode will be less.For physical hydrogels,water molecules are tightly bonding with the polymer backbone through hydrogen bonding or electrostatic interactions,but with the poor mechanical properties.For chemical hydrogels with three-dimensional structure,there is a drawback that it cannot be recovered when it is severely damaged.To realize the prospect of zinc metal battery driving flexible devices and large-scale energy storage,hydrogel system with high safety and long-cycle needs to be constructed.Herein,the polyzwitterion hydrogel electrolyte(PZHE)with poly-3-[N,Ndimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid internal salt(PSBMA)skeleton is prepared by thermal polymerization.The aqueous zinc metal battery is assembled with PZHE.The research reveals that the symmetrical battery showed excellent cycle stability at different current densities and PZHE shows excellent adaptability with different cathode.What’s more,the experiments verify the practical application of PZHE in quasi-solid state flexible batteries.