Preparation and properties of PVA-PAA-KOH alkaline polymer electrolyte membrane

PAA was prepared by the situ polymerization of AA with various neutralization degrees in PVA solution under the action of initiator and crosslinker and PVA-PAA blended membrane was prepared by the solution casting method. PVA-PAA-KOH alkaline polymer electrolyte was activated by the alkaline solution. The morphology and structure of the polymer electrolyte were characterized by means of SEM, XRD and FT-IR. The electrochemical properties were represented by the AC impedance and the cyclic voltammetry. The results indicated that a homogeneous PVA-PAA blended membrane was successfully obtained. The increased water content of the membrane and the decreased crystallinity of the PVA owed to the presence of PAA. The maximum ionic conductivity of the electrolyte reached to 3.55×10^-2 S/cm. The alkaline polymer electrolyte with 7:3 mass ratio of PVA:AA could achieve a good synthetical property with electrochemical stability window more than 2 V and could meet the demands of MH-Ni battery.