Highly Swellable Hydrogel Electrolyte for Metal Air Battery

Gels have three-dimensional cross-linked polymer network, which can extensively swell in water or hydrophilic solvents depending on their structure. High swelling property of the hydrogels can be very beneficial to use them as electrolyte material for battery application. Among the energy storage devices like lithium-ion, nickel-cadmium, and lead-acid batteries, metal-air batteries have the advantages of higher capacity and energy density. In this work, our aim is to use highly swellable hydrogel as electrolyte, Aluminium as metal anode and Carbon-Manganese composite material as cathode. Gel polymer electrolyte is a well-studied and most widespread field for Li-ion batteries and electrochemical devices as they offer many advantages such as no internal shorting, leakage of electrolytes and non-combustible reaction products at the electrode surface existing in the liquid electrolytes. But high cost, low life and capacity, poor ionic conductivity and difficult processing are the common drawbacks of gel polymer electrolytes. To overcome these problems we approached in a very fundamental way of using common electrolyte solutions like NaCl, KCl, NaOH, KOH etc., which will be absorbed by the neutral monomeric N, N, Dimethylacrylamide (DMAAm) hydrogel which can be very low cost and easy to re-swell whenever electrolyte goes down. DMAAm hydrogel was synthesized by single step photopolymerization method in presence of initiator Benzophenon (BzPh) and crosslinker N , N' -Methylenebisacrylamide (MBAA). Prepared gels were swelled in different concentration of aqueous electrolyte solutions to study their swelling, mechanical and electrochemical behavior. As battery performance depends on both the electrolyte and electrode, so we also investigated the morphology of the electrode we used. Finally the battery performance and critical issues are taken into account to make the current method practically functional. This work can make real contribution to the field of metal air battery and develop new viewpoints in the field of gel electrolyte materials.