Effect of mixed cations in synergizing the performance characteristics of PVA-based polymer electrolytes for novel category Zn/AgO polymer batteries-a preliminary study

Thin films of polymer electrolytes comprising of PVA and KOH (A) with and without the addition of zinc salts, viz., zinc acetate (B) and zinc triflate (C) as mixed cations were prepared via. solution casting method. The thermal stability and ionic conductivity of PVA-KOH solid polymer electrolyte (A) were improved by the partial substitution of KOH with zinc salts. Among the two salts, zinc triflate was found to improve both the physical as well as electrochemical properties of the PVA-KOH films more significantly than zinc acetate. An attempt to optimize the ratio of various components of polymer electrolytes, viz., polymer: KOH: zinc salt was also made, based on the dimensional stability and ionic conductivity values. Finally, the select category polymer film containing PVA-KOH-zinc triflate (C) in an optimum ratio of 40:35:25 was deployed in coin cell fabrication and subjected to charge-discharge studies with a view to demonstrate the possible electrochemical reversibility characteristics. Based on the encouraging results obtained from the cycling study, C type films [PVA-KOH-zinc triflate] qualify themselves as potential polymer electrolytes for use in rechargeable Zn/AgO polymer batteries.