Dr. Yashodhan Gokhale was the 1st employee to start Octillion India operations in October 2016. By June 2022, he was leading innovation in Energy storage as Vice-President at Kalyani Powertrain-KPTL, which is the 100 per cent subsidiary of Bharat Forge under Kalyani group. The passionate battery specialist speaks to Aditi Kelkar about alternatives for lithium ion and latest battery design technologies.
How do you see the Li Ion battery energy storage opportunity in India?
We are in the right era, because now the lithium-ion technology is maturing. Lithium-ion batteries started in 1980s in a lab by Prof. Goodenough and his breakthrough technology is used in mobile batteries, batteries in space programs, drones, marine applications and in laptops everywhere in the world. In a country like India, the matured Lithium-ion battery technology makes a lot of sense for our electric mobility domain.
Today Lithium battery energy storage is the most cost-effective flexible solution to solve grid issues. Do you think in the long term we will require broader range of technologies that can provide long duration energy storage where lithium ion may not be suitable?
Very good question. Lithium-ion batteries have their pros and cons. After the Russia Ukraine war, the prices have shot up by more than 30% in China. If China hikes their price, then all prices go up in the battery domain. There are some other technologies apart from Lithium ion such as Sodium, Hydrogen fuel cell which give a good alternate solution for grid storage application. Other technologies such as Vanadium Redox flow are also there but they will take time to mature. Manufacturability plays an important role. At the end of the day, battery technology should be cost effective, sustainable and safe. People are trying and in the next 2-3 years we should get more mature solutions. Lithium-ion technology was developed in the 1980s and has only now matured as a technology. People keep developing new materials for anode and cathode. So, I think for grid storage, hydrogen and sodium can be a good answer.
Give us an overview on different battery chemistries?
Most commonly used battery chemistry in Lithium-ion batteries is LFP: Lithium Iron Phosphate. After LFP, it took a few years for NMC (Nickel Manganese Cobalt) to mature. NMC is commonly used by leaders such as Panasonic, LG, Samsung and CATL. LMO (Lithium Manganese Oxide) and LTO (Lithium Titanate) are also used. LTO is very expensive because of the titanium used in it, but LTO batteries are very safe, stable and can survive over longer periods. Every battery chemistry has its pros and cons based on its energy density and power density. Materials like LTO are suitable for high power and materials like NMC, NCA (commonly used by Tesla) are used for high energy density applications. But due to challenges of temperature and cost efficiency, people are shifting to LFP due to its longer cycle life, better safety and better cost. Major players in this domain are Panasonic, LG, Samsung, CATL, BYD, Northvolt (Sweden). Many companies in India such as Reliance, Amararaja, Exide, Leclanché, Ola are trying with the help of the Government's PLI scheme.
Is this entire demand for Lithium-ion batteries driven by the automotive sector? What is the storage market beyond eight hours and what are the leading technologies in that area?
Lithium-ion batteries are mainly used for high energy density applications covered by the automotive segment. The batteries are also used for storage. But 8 hours is still a big challenge which is currently served by digi-gensets. Lithium-ion can be used for up to 4-hour long applications, but for 8 hours it becomes very expensive. People are trying Vanadium redox flow batteries, zinc, bromine-based chemistries but maturities will take time. People are exploring fuel cells but ROI is a challenge in making a business case. So, currently Lithium-ion batteries are used with microgrid storage.
What’s your opinion on the battery swapping policy?
Battery swapping policy works for the two-wheeler domain. I still have my reservations for three-wheelers. If you design and develop any battery pack for two wheelers like Activa or Jupiter, the main aim is to anyone who drives an average of 35 km per day. For such usage, the charge-discharge cycle and longevity of the battery is very important. At the end of the day, one can remove the 12-13 kg battery to be taken home for charging. But here again safety is a crucial concern in the battery swapping mechanism. Three-wheeler battery weight is a major constraint. Second important constraint is the expensive battery connector. The 3W battery cannot be removed from its location too frequently. Government has taken good initiative in 2W batteries and good swapping mechanisms are coming up in India.
What are the few of the enabling technologies that are critical to energy storage?
Energy storage will be focussed around Lithium-ion batteries for a few more years owing to the maturity of the technology. New chemistries evolve in labs but the main challenge is to make them manufacturable. Hydrogen storage should also mature during this time in terms of safety and cost viability. India really needs energy storage and we should strive to be self-sufficient, ‘Atmanirbhar’. We are underutilising solar energy due to challenges in solar cell efficiency based on silicon technology. But we can do storage in a cost-effective way to make up for it and to achieve grid stability.
How many legacy automakers will successfully transition from Analog machine assemblers to hardware/software/battery companies? With batteries at the core, will most automakers also transition into energy storage business?
I feel that not many players can. Normally in an IC engine vehicle, there are over 300 parts subjected to wear and tear. In an EV, these parts subjected to regular wear and tear are reduced to approximately 200 or even fewer. Hence the suppliers whose parts go into EVs or energy storage systems have to find other ways to bring in the same revenue. They will therefore venture into manufacturing of chargers, busbar connectors, other smaller assembly items which can go into a battery pack or electrical motors. For energy storage, they choose not only Lithium ion but also other alternative chemistries such as Vanadium Redox Flow, Nickel Metal Hydride or Hydrogen fuel cell. Since upfront costs are very high, they go for collaborative work or limit their scope to technology transfer.
Existing IC engine parts suppliers will try to make parts for EV; the fuel engine, fuel tank will be replaced by battery, e-axle and electric motor. They have to now manufacture magnets, wiring harnesses and good quality connectors.
Please tell us more about the research focus on battery design.
One of the new battery research design technologies is the cell-to-pack technology. Although there are challenges, there are good improvements like almost 10% reduction in weight, the batteries can be chassis-mounted, etc. The whole automotive industry is in favour of chassis-mounted batteries due to better weight balance and weight ratio while driving the car. Sleekly designed battery packs are the way forward as it improves the energy density by 10-15% as compared to normal batteries where people go from cell to module to pack which is managed by an external intelligent battery management system. These packs can comply with different certifications such as USABC, ARAI ICAT in India with AIS 038, 048 new standards which take care of shock and vibration, thermal runaway issues and such.
Do you think there’s a shortage in the skilled workforce in this domain?
That’s a very good question, Aditi. Although we are growing with new technologies, we are yet to adapt to different techniques. One has to have a holistic understanding of things, everything together. You need a chemist, a physicist, an electrical and a mechanical expert, with hands-on experience. There are different softwares like SolidWorks, Ansys, Catia to design batteries. But when you think about manufacturability, things can vary greatly. Skilled workforce is a big challenge and people need to be trained to work on high voltage systems of the order of 720-800V. So along with the on-the-job training, I want to encourage universities to incorporate partial hands-on training in the curriculum to boost the sector and industry. All industries are facing a shortage of semiconductor chips. At some point India will have to think about having our own fabs, foundries that we currently don’t have any of. We depend on our neighbouring countries for it and we have to find an alternative solution for the same.
What would you want to leave the readers with on account of the 75th Independence Day and India’s foray into EV?
The last century was revolutionised by IC (integrated circuits). This century is also about IC (India and China). At the moment, the dominance of C (China) is more than that of I (India). When India becomes truly dominant, we can push for Make in India. There are many good startups maturing into good companies such as Ather Energy in the EV domain. At some point we have to create a truly Atmanirbhar Bharat. Big companies in India make complex products such as BMS (Battery Management System) for say Volkswagen or Audi. It is high time that they start making it for the Indian OEMs. My message to everyone is to buy Electric since it is lighter on the carbon footprint and it’s our responsibility to pass on a safer environment to the next generation. Don’t worry about the range because that will be resolved in due time. Although the prices are high currently, the overall ROI is very competitive and lucrative. So, go green, go Electric!