Flexible Polymer Electrolyte with Ethylene Glycol/Water Eutectic Solution for High-Performance and Anti-Freezing Zn-Ion Batteries
발표자
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초록
내용
Aqueous rechargeable zinc-ion batteries face several challenges that hinder long-term stability associated with dendrite growth, and limited low temperature operation, due to water freezing. Here, we provide a solid polymer electrolyte (SPE) with anti-freeze properties by incorporating a eutectic solution of ethylene glycol (EG) and water into poly(arylene ether sulfone)-graft-poly(ethylene glycol). The optimized sample, 1.0 M Zn-Eutectic-SPE, shows the outstanding properties, as it exhibits impressive ionic conductivity of 3.32 mS cm-1 and the zinc transference number of 0.68 at room temperature (RT), still maintaining a high ionic conductivity of 0.152 mS cm-1 even at -20 oC. The tensile strength of 1.0 M Zn-SPE is quite high at 4.39 MPa with mechanical flexibility at RT and -20oC. Based on these properties, the rechargeable Znǁ V10O24.nH2O@rGO cell fabricated with 1.0 M Zn-Eutectic-SPE electrolyte and binder shows an excellent capacity retention close to 100% Coulombic efficiency even after many cycles at both RT and -20 oC.