Indian
Institute of Technology Madras researchers are developing
mechanically-rechargeable zinc-air batteries as an alternative to lithium-ion
batteries which are used in electric vehicles.
The
researchers, who have filed for patents for this new battery technology, are
collaborating with major industries to develop these zinc-air batteries. They
are economical compared with existing lithium-ion batteries and have a longer
shelf life. Zinc-air batteries can be
used in two-wheeler and three-wheeler EVs.
The
Indian Electric Vehicle sector has been growing rapidly in recent years
following the Government of India’s favourable policies and the increasing call
to reduce pollution.
Lithium-ion
batteries are widely used in EVs. China, which is a major manufacturer of
lithium-ion batteries, dominates the EV battery manufacturing sector.
Currently, Indian EV manufacturing firms import lithium-ion batteries mostly
from China.
Although
lithium-ion batteries are widely used, there are several limitations such as
limited availability. Further, the diverse requirements of the Indian market
cannot be fully met by lithium-ion batteries alone.
Dr.
Aravind Kumar Chandiran, Assistant Professor, Department of Chemical
Engineering, IIT Madras, and his research group have been working towards
developing a cost-effective alternative to Lithium-ion batteries. They focused
on Zinc-Air Batteries as Zinc is a widely-available resource.
FUTURISTIC MODEL
Dr.
Aravind Kumar Chandiran, Assistant Professor, Department of Chemical
Engineering, IIT Madras, said, “Our Research Group is developing a futuristic
model for zinc-air batteries for EVs. Through this research, we are also
identifying shortcomings in existing technology and finding ways to address
them. The Research team has currently developed zinc-air cells and is working
towards developing zinc-air packs for EVs.”
The
researchers are mooting separate ‘Zinc Recharge Stations’, similar to petrol
stations. The EVs Users utilising zinc-air batteries can reach out to these
bunks whenever the batteries are drained, similarto the current model of
conventional vehicles refuelling at petrol stations.
This
technology is based on ‘Battery Swapping’ in which vehicle users can swap used
‘zinc cassettes’ of the battery with fully-charged ‘zinc cassettes’ at these
‘Zinc recharge stations.’
Elaborating
on this aspect, Dr. Chandiran said, “This is a major advantage of the zinc-air
batteries as currently the only option available with the lithium-ion batteries
is that the entire used battery pack has to be removed and be swapped with a
complete lithium-ion battery pack. This results in double the capital
investment in the case of lithium-ion batteries.”
The
researchers are also mooting to recharge the used ‘zinc cassettes’ through
solar panels.
Speaking
on the significance of the project, Akhil Kongara, a Research Scholar, IIT
Madras, said, “According to the proposed plan, a EV user will only have to
spend a few minutes at the ‘zinc recharge stations’ to swap ‘zinc cassettes’.”
Gunjan
Kapadia, another Research Scholar working on the zinc-air batteries and
lithium-ion batteries operational safety at IT Madras, said, "The
indigenously developed zinc-air batteries, specifically in an Indian context,
are extremely safe as it has aqueous electrolyte and it doesn't catch fire even
in worst case scenario of EVs accident"
Advantages
of zinc-air batteries include:
·
Zinc is widely available in India and would
reduce the import of lithium-ion batteries
·
Zinc is cheaper as compared to lithium-ion
batteries. While lithium-ion batteries cost $200 to $250 a KWhr, zinc- air
batteries cost around $150 KWhr. With wider usage, the price is expected to
come below $100 KWhr
·
Zinc-air batteries are also water-based and have
a longer shelf life.
·
Zinc-air batteries have good turnaround
efficiency.