Researchers From IIT Madras Developed The First Rechargeable Iron Ion Batteries In The World

Harin - Aug 29, 2019

IIT Madras researchers have created the world’s first-ever rechargeable battery that, instead of using lithium, uses iron ion.

Lithium has long been a popular replacement for Nickel-Cadmium in manufacturing rechargeable batteries. But now IIT Madras researchers have created the world’s first-ever rechargeable battery that, instead of using lithium, uses iron ion. On the official website of IIT Madras, a post described how the new technology makes use of low-carbon steel anode, a vanadium pentoxide cathode, and an iron chlorate electrolyte.

The research team claims that compared to existing lithium-ion technology, iron ion batteries will be more cost-effective as well as safer and more stable. Since iron doesn’t generate dendrites, short-circuits are prevented when discharging electricity. The new technology will help make batteries that have better storage capacity.

The team consists of Dr. S. Ramaprabhu, Ms. Sai Smruti Samantaray, and Ms. Ajay Piriya V.S. who are all from the Physics department of the institute. According to the team, there are many benefits to using iron rather than lithium, due to its favorable chemical and physical properties. Iron, unlike other metals, has a cheaper price, smaller ionic radius as well as favorable redox potential. While manufacturing lithium-ion batteries requires a controlled environment because of its highly volatile and sensitive nature, iron-ion batteries can be made in ambient environments. However, due to these benefits being overlooked, previous research hasn’t delved into using iron in making rechargeable metal-ion battery.

Put aside all the benefits, there are still a few problems to iron ion batteries that it may not yet be ready as a replacement for lithium-ion in making rechargeable batteries. The biggest problem is that iron ion batteries are only capable of around 150 charging and discharging cycles, which isn’t up to par with lithium-ion batteries. Another problem is energy density. Iron ion batteries, at the moment, can only reach about 220Wh/kilo, compared to 350Wh/kilo of lithium-ion batteries.