Preparation of PVA-based composite alkaline solid polymer electrolyte with La 2 O 3 nanoparticle filler

Solid polymer electrolytes have promising applications in a wide variety of fields compared with liquid electrolytes; however, the promotion of ionic conductivity is still necessary and the composition with nanoparticles is an effective way. In this paper, the composite alkaline solid polymer electrolyte membrane is prepared from poly (vinyl alcohol) (PVA) and lanthanide oxide (La 2 O 3 ) nanoparticle via solution casting method. The addition of La 2 O 3 nanoparticle can hinder the crystallization of PVA, so as to obviously improve the ionic conductivity to 0.086 S·cm −1 with the content of 12 wt.%. Moreover, a three dimension of multi-porous structure is observed by SEM and abundant KOH electrolyte can be retained. Besides, an electrochemical stability window of 1.6 V is obtained. The conductivity is influenced by the temperature and the ratio between KOH and PVA, remarkably. In addition, nickel metal hydride battery is assembled with the discharge capacity of about 230 mAh·g −1 , indicating that the PVA-La 2 O 3 -KOH ASPE is viable for utilization in Ni-MH battery. Graphical abstract