Al₂O₃-incorporated proton-conducting solid polymer electrolytes for electrochemical devices: a proficient method to achieve high electrochemical performance

A new series of proton-conducting solid polymer electrolytes with different compositions, comprising polyvinylpyrrolidone (PVP_K40) and polymethylmethacrylate (PMMA) as host polymers, methanesulfonic acid (MSA) as a proton-conducting salt, and alumina (Al₂O₃) as the nanofiller, were prepared using solution casting. High proton-conducting samples were identified and utilized for the construction of primary proton batteries. The electrical properties of the prepared electrolytes were investigated through AC impedance analysis. The highest proton conductivity (2.51 × 10⁻⁵ S/cm) was achieved at room temperature by PMMA-PVP_K40-MSA-based blended polymer electrolytes (BS3). The discharge characteristics of filler-dispersed solid polymer electrolytes were better than those of other solid polymer electrolytes. The estimated energy density of the constructed proton battery using solid polymer electrolytes with blended polymers and nanofillers was 0.66 and 3.25 Wh kg⁻¹, respectively.