Effect of Ti3AlC2 MAX phase on electrochemical performance of thermo-responsive copolymer electrolyte for solid state zinc-ion battery

Abstract

The solid-state zinc-ion battery (ZIB) is environmentally friendly, cost effective, and extremely safe, which are essential features for alternative sustainable energy storage systems. Herein, a polymer composite electrolyte (PCE) is successfully developed through a facile solution-casting approach from a thermo-responsive copolymer-based electrolyte and layered ternary carbide (Ti₃AlC₂). The thermo-responsive copolymer demonstrated synergistic mechanical properties through the addition of an appropriate plasticizer and a zinc salt. This combination suggests that the material possesses thermal self-protection capabilities due to its anti-Arrhenius ionic-conducting behavior. However, parasitic reactions and dendrite formation hindered the achievement of its full potential. The incorporation of Ti₃AlC₂ or MAX phase can mitigate the above obstacles, enhancing electrochemical performance with excellent flexibility and maintainable self-extinguishing. The solid-state ZIB benefits from the well-designed PCE with the expanding layer interspacing, delivering a remarkably high capacity (336 mAh g⁻¹ at 0.1 A g⁻¹) and energy density of 242 Wh kg⁻¹. This is achieved due to the Ti₃AlC₂′s ability to immobilize or entrap triflate anions via electrostatic forces. Therefore, the designed PCE is a promising step toward the development of flexible solid electrolytes in ZIBs.