New Delhi, Jun 24 (IANS): The Union Ministry of Science & Technology said on Thursday that the ARCI has developed cost-effective catalysts for metal-air battery which can decrease cost and increase the efficiency of metal air batteries.

"A new non-precious metal-based bi-functional electrocatalyst (capable of catalysing two different types of reactions) can decrease cost and increase the efficiency of metal air batteries," said a statement issued by the ministry.

It said that with the rise in demand for different energy sources, worldwide efforts are being made to develop different kinds of energy devices, such as lithium-ion batteries, lead-acid batteries, redox flow batteries, lithium-air batteries, zinc-air batteries, sodium-ion batteries, fuel cells, and super capacitors.

The International Advanced Research Centre for Powder Metallurgy and New Materials (ARCI), an autonomous R&D centre of the Department of Science and Technology (DST), Government of India, has developed the cost-effective electrocatalyst by anchoring transition metal ions into the sulfur-doped carbon framework via carbonisation of a polymer called sPEEK (sulphonated polyether ether ketone).

This catalyst synthesis method can also be used to recycle used ionomers (polymer composed of both neutral repeating units and ionised units).

The catalyst also leads to reduced voltage polarisation, enabling higher energy efficiency and a stable charge-discharge characteristic.

The results obtained were comparable to that of conventionally used noble metal-based catalysts with metal loading of 20 per cent or higher. The research has been published in the journal ACS Applied Energy Materials.

The scientists have used an ion-exchange strategy that positions the metal ions in the carbon framework homogeneously, limits the particle size and offers control on composition and size at a very low loading of transition metal.

Cost-effectiveness is thus achieved by low loading of transition metal, high activity, and high cycling stability compared to many of the catalysts earlier reported.

Among them, Zn-air batteries have drawn significant attention due to their low cost and high energy density. They are compact power sources for portable electronics and electric vehicles and energy storage devices to manage energy flow among renewable energy generators, such as wind turbines, photovoltaic panels, electric grids, and end-users.