The figures are well known and very daunting: Net Zero by 2070; 500GW of energy from renewable sources only by 2030; at least 50% of energy requirements to be met from renewable sources by 2030. As a snapshot, these are the three numbers that define India’s short term and long-term objectives in the country’s race towards a green future.
Energy storage will have a major role to play to make this happen. This is a challenge that the nation will have to address as, beyond limited pumped hydro and scattered lead-acid deployments, there is little evidence of domestic expertise in large-scale energy storage to date.
The Indian Government has recognised the importance of energy storage for the future, and has come up with a slew of initiatives and incentives. It is inviting entrepreneurs to come forward and invest in introducing state-of-art technologies in areas, including storage, to help realise its goals.
Competency in electrochemical storage on a commercial scale is almost non-existent (except for lead-acid). There is now a furious scamper, particularly in the lithium technology arena, to acquire overseas knowhow – mostly from China – to secure the supply-chain and set up manufacturing plants in India to cater to the emerging market.
In the uncertain political environment, dependence on an overseas partner, especially one that has a loaded geo-political agenda, is unwise. Risk coverage for the future is a must and, preferably, this should be carried out through home grown initiatives.
Pushed by the government, every automobile manufacturer has laid out plans for unveiling a string of electric cars to be launched over next five years, and almost every plan is based on cell import from China. This is putting the nation in a highly vulnerable position where all the basic foundations – transportation, communication and digital initiatives to name a few – are mortgaged to the continued trade, mostly one- way, with a partner with whom India has never been comfortable politically or economically.
Recognising the gap, over the past 10 years, the government has taken several steps to trigger action at both ends. Firstly, introducing manufacturing capability in the country of what has been defined as ‘advanced chemistry cells’ through production linked incentives. Secondly, funding extensive research in academia and other institutions, including those in the private sectors, and developing the competence to produce advanced storage solutions at a globally competitive technical and commercial level. The results of these initiatives have become increasingly visible in recent years, with many laboratories and their leadership proudly unveiling homegrown innovations that inspire confidence in the country’s trajectory.
Given the scale of the estimated energy storage capacity that the country requires to support 500GW of renewable energy by 2030, pumped hydro storage would remain a preferred technology for bulk storage wherever the geography would permit. India already has several installations, spread across the nation, developed entirely with indigenous capability, which have been working well for the past two decades. One can say that in this field India has adequate technological coverage and can go for implementation wherever the technical and economic viabilities are positive.
The gap is in the arena of electrochemical storage. Talking to a large number of researchers across the country, representing some of the best known institutions, it seems that while there is significant interest in unravelling the challenges of the solid-state lithium configuration as well as lithium-sulfur, the country has moved on. It is now primarily focusing on flow battery and sodium-ion technology as the ultimate deal clinchers for the nation’s storage aspirations. India, primarily a lead-acid country with excellent collection and recycling infrastructure, continues to work on upgrading the lead-acid framework to a more competitive standing vis-à- vis LFP – particularly for LDES applications. This is in both conventional configurations and the more exotic lead-redox flow variants.
It is fascinating to interact with some of the leading names in the nation who are at the forefront of this massive effort in the race towards ‘independence’ in mastering the technical competency of emerging storage technologies. However, to mention a few is not fair, as many would remain unnamed, which is unavoidable due to the limitations of space. However, the purpose here is to highlight the entire Indian scientific community’s effort and not to just focus on any individual excellence.
We start with the grand old man of the Indian battery community, Professor Ashok Shukla, whom we first met more than 30 years ago. Prof Shukla received his PhD from IIT, Kanpur in 1974 and for more than 40years has been working in various fields of electrochemistry, with particular focus towards electrochemical storage. He has mentored a countless number of students who have subsequently worked on their own or had their own research team, and some even turned entrepreneurs.
Prof Shukla is a Humboldt Foundation Fellow of the Technical University of Hannover and continues to be associated with the Indian Institute of Science (IISc) as emeritus professor in the department of Solid State and Structural Chemistry. On being asked which work gave him the most satisfaction he referred to his work on nickel-iron cell development from concept to pre- commercial prototypes. He mentioned that his greatest regret is that no one really appreciates the simplicity and strength of the nickel-iron system and hence it remains as a research entity and never progressed into any commercial space. One other concept that he has strongly projected is the lead-redox flow battery – which some of his students are actively pursuing. A highly honoured scientist of the country, Prof Shukla continues to remain closely associated with the department and the various research projects being pursued therein.
As a person who is known for his developments being invariably India-centric and ready to implement, Professor Kothandaraman Ramanujan has carved a niche for himself in the field of energy storage research in the country. Introduced to the world of electrochemical material science by Prof Shukla at IISc, Bangalore, Prof Ramanujan received his PhD in 2006 and followed it up with two consecutive post-doctorate stints in the US and Canada, before he settled down at the Indian Institute of Technology, Madras (IITM), in 2011.
Since then, he has been working on various aspects of electrochemistry with a major focus on lithium/sodium/zinc/vanadium-based batteries. Prof Ramanujan has looked deeply into the options for flow battery chemistry, with at least two of his projects having matured to the commercial or field-proto testing stage. The zinc-bromine flow battery developed by him and his team has now been fully transferred to an Indian corporate.
Yet another configuration that he worked on – a vanadium-redox flow system (10KW/0.1MWh) – is currently undergoing a field proto evaluation by the end user. Presently pursuing a zinc-iodine configuration, the team has already achieved a decent energy density of 110Ah/l and is optimistic that it will achieve even higher numbers.
Interestingly, India – primarily a lead-acid country with a well- established ecosystem to manage the lead-acid life cycle – continues to show strong interest in advancing the technology to meet the evolving demands of energy storage applications. A lead-redox flow battery is an interesting option that is being pursued by Prof Ramanujan and his team, with a reported achievement of 500 cycles at 100% DoD. These results are remarkable and worth pursuing. The journey doesn’t stop here, as the professor is pushing for yet another version of flow – the organic redox flow.
However, it is not flow versions to which IITM is limited; the institute is also working on electrolyte development for both polymer and solid-state versions of lithium and sodium batteries. Prof Ramanujan’s passion for research, particularly in electrochemistry, extends beyond his laboratory and he has also been performing numerous outreach activities on popularising electrochemistry through the ECS-IITM Student Chapter since 2022 (ecsiitm.com).
He has published more than 170 research articles, obtained nine patents, completed two technology transfers, and completed 28 sponsored and 16 consultancy projects. He has an honorary adjunct faculty at the University of Southern Queensland, Australia, actively collaborating on green technologies including the recycling of lithium-ion batteries. A life dedicated to electrochemistry that serves the priorities of the nation is his only motivation and continued interest.
And this brings us to other storage options, particularly the sodium-ion story. India, like the rest of the world, trying to shake- off the stranglehold that China holds in lithium-ion cells and material supply, has put all its bets on the successful maturing of the sodium-ion system. Recent news coming in from China on the launch of this chemistry in some new vehicles, in preference to lithium, has only added to the urgency of the combined efforts going on in various Indian laboratories to arrive at a robust commercial- scale knowhow.
At the forefront of this cutting- edge research is Professor Amartya Mukhopadhyay and his team at the Indian Institute of Technology in Bombay. Prof Mukhopadhyay has a PhD in Material Science from Oxford in the UK and is currently engaged as a Professor of Metallurgy and Material Science at the Indian Institute of Technology, Bombay (IITB). His research output has been prodigious, with more than 60 publications in the field of materials for electrochemical storage only and 16 patents which are granted and another three on the way.
A highly awarded scientist, Prof Mukhopadhyay’s other outstanding contribution to the field of electrochemical storage is his role in setting up a national ‘Battery Research Society of India’, drawing members from the entire electrochemical storage world from India and abroad. The first plenary session of the newly formed society is scheduled for December this year. It is expected to be very heavily attended by experts from across the world and to set the agenda for future work that will benefit not only India but the entire scientific community.
The team at the Advanced Batteries and Ceramics Laboratory, IIT Bombay, under the guidance of the young, energetic professor, works on advanced battery chemistries: from concepts to materials to electrodes to cell development and prototyping; addressing various issues, as well as developing new and improved technologies.
At present, the battery chemistries include next-generation Li-ion, Na-ion, K-ion and solid-state. The team has a major focus on Na-ion battery chemistry, which can yield sustainable energy storage technology that is free from critical minerals and import dependencies. It also has the edge over Li-ion battery technology when it comes to fast charging capability, temperature window of operational, and safety aspects.
The team is a group of around 25 researchers, which include post-doctoral researchers, PhD students, Masters students and project associates. While capable of carrying out most of the research in-house, the group simultaneously collaborates with other universities, national laboratories and industries.
For example, there are ongoing formal collaborations with University of New South Wales and Monash University, Australia. Collaboration with other government-of-India laboratories such CSIR-CLRI, RRCAT, India, is also frequent. This collaboration is mainly to harness complementary and supplementary expertise to help understand some scientific aspects more thoroughly.
Explaining some of the breakthroughs the team has achieved, Prof Mukhopadhyay highlighted:
- Development of high capacity and air/water-stable ‘layered’ Na- transition metal oxide-based cathodes for Na-ion batteries. This could go a long way in simplifying the electrode preparation methodology, making it safer and less expensive.
- Development of high Na-containing P2-structured ‘layered’ Na- transition metal oxide-based cathodes for Na-ion batteries. This involves discovery-cum-innovation pertaining to the composition structure of such materials, which is very important in elevating the energy density of Na-ion batteries to a much higher level – perhaps beyond that of LFP battery chemistry – while also ensuring high power density.
- Development of stable ‘alloying-reaction’ based anodes for Na-ion batteries, which is important towards bestowing Na-ion batteries with very high energy density, as well as further improved safety aspects (by getting rid of hard carbon-based anodes), but without compromising on cycle life.
In the lithium chemistry domain, the team has also achieved significant success. Though previously thought to be very challenging, if not impossible, they have been able to develop water-stable, less cobalt-containing ‘layered’ lithium transition metal oxide-based cathodes for next-generation lithium-ion batteries. This will render the lithium-ion battery technology less expensive, more sustainable and with ecofriendly fabrication.
The list goes on for the different laboratories in India, who are working on energy storage, as well as the significant research output that is coming out of these institutions. Those named here readily come to mind, but there are at least another eight to 10 significant institutes – across government-run academic institutions and the private sector – engaged in highly challenging work in energy storage, spanning Li-ion, Na-ion, metal-ion, flow and hydrogen chemistries.
It is time for the world to take notice of these centres of excellence – led by brilliant, charismatic minds like the few named here – who are poised to become stars in the future world of energy storage.
