PLASTICIZED PVA/PVP–KOH ALKALINE SOLID POLYMER BLEND ELECTROLYTE FOR ELECTROCHEMICAL CELLS

Abstract

Solid polymer electrolytes comprising a blend of poly (vinyl alcohol) (PVA) and poly (vinyl pyrrolidone) (PVP) with different concentration of potassium hydroxide (KOH) as ionic dopant were prepared using a solution–casting technique. The conductivity was enhanced to (1.5 ± 1.1) × 10 -4 S cm -1 when 40 wt.% KOH was added. The highest conductivity exhibited when 20 wt.% ethylene carbonate (EC) and 30 wt.% propylene carbonate (PC) was added into the PVA/PVP–KOH sample electrolytes. Conductivity–temperature dependence of the plasticized samples was established to obey an Arrhenian relationship with the activation energy of the order of 0.08–0.4 eV, depending on the plasticizer concentration. Electrochemical cells of Zn|PVA/PVP–KOH + EC|MnO 2 and Zn|PVA/PVP–KOH + PC|MnO 2 have been fabricated. The discharge characteristics of the cells are considered under a constant current of 1 mA. The open circuit voltage (OCV) and discharge capacity of the cells are measured.