Introduction of Al(III)‐Ion‐Based Solid Polymer Electrolyte Material for Energy Storage Device Applications

Abstract

Solid phase electrolyte system PVIm‐R‐PEG‐AlCl₃ is introduced for Al(III) ion‐based energy storage material. Here, we introduced [AlCl₃Br]⁻ counter anion system with N‐octyl‐polyvinyl imidazolium polymer matrix supported by PEG. Electrolyte material shows good thermal stability with a Glass transition temperature (T_g~148 °C), which provides a good working temperature range for material processing. PVIm‐R‐PEG‐AlCl₃ shows electrochemical stability of 1.5 V and red‐ox properties, it has 96 % of ionic conduction against the Al metal. The conductivity of electrolyte material is found in the range of 10⁻⁵ S/cm at room temperatures and 10⁻⁴ S/cm at higher temperature (>40 °C). The polymer electrolyte matrix shows the mobility of 1.37×10⁻⁶ m²/Vs and drift ionic velocity of 3.42×10⁻⁴ m/s at 30 °C. The ionic movement of Al(III) ions inside the matrix follows correlated type hopping with the activation energy of 0.266 eV. This Al(III) ion‐based solid polymer electrolyte (SPE) is associated with a large amount of capacitance with a tiny electrode contribution.