Lithium-ion batteries are widely used these days in various electronic devices due to their higher energy density. There are several drawbacks with this battery that we all are aware of. For instance, they need protection from overcharging and prevention from short-circuiting. Also, the cost of lithium is rising up due to the increasing demand for lithium-ion batteries in electric vehicles. The extraction of these materials is also quite difficult as most of the countries which have its stock have either government limitations or lots of Mafias are involved in it. Thus exploring new battery chemistry to overcome these drawbacks will be a step forward in meeting the growing energy demands.
A research team from Indian Institute of Technology-Madras (IIT-Madras) has officially developed the world’s first iron-ion battery. The newly-developed battery promises a low-cost stable alternative to the existing mainstream lithium-ion battery. They had developed this iron-ion battery using an anode made from low-carbon steel, instead of pure iron, along with a cathode made of vanadium pentoxide, which is suitable for the movement of iron ion, due to its larger gap.
The iron-ion battery is also equipped with an electrolyte made using iron chlorate. Developed by them only, the battery is much more cost-effective and features slightly better storage capacity and stability compared to the traditional lithium-ion batteries.
According to the IIT-Madras research team, iron-ion batteries are also safer to use than lithium batteries due to the inability of iron to produce dendrites during the charging process and therefore, prevents short-circuiting of the batteries.
The other notable benefit of iron-ion battery is its favourable physical and chemical properties. “The redox potential of iron ion is higher than lithium-ion, and the radius of the Fe2+ ion is nearly the same as that of the lithium-ion,” the team claims, adding that these two favourable properties of iron have been overlooked for so many years. And that’s the reason why they don’t have iron ion rechargeable batteries.
Also, this battery has significant power retention after multiple charging cycles. But there are certain limitations, such as it is capable of only 150 cycles of charging and discharging for the time being. At the present stage, the energy density of the battery is also only able to reach around 220 Wh/kilo, which is only around 55-60 per cent of the 350 Wh/kilo of energy density for lithium-ion battery.
The team is working on its limitations and we can hope to get something big and revolutionary soon.