How Audi-Supported Startup Nunam is Giving EV Batteries a Second Life - Co-Founder Prodip Chatterjee

In 2016, Prodip Chatterjee and Darshan Virupaksha were spending time in rural India, where they could see the energy-related challenges that the people have to live with. Regular power outages are quite common in the places that do receive electricity, and  energy storage is rarely an option because of affordability.

“For a backup system, one of the most expensive components is the battery, which usually is a lead-acid battery. Now, this battery does not last very long, is quite bulky and is not really that good overall. While it is cheap and somewhat affordable, it just doesn’t have a good lifespan. That got us thinking about what could be done to reduce the cost and to address this problem,” Chatterjee tells Auto Futures.

The duo began experimenting with used laptop batteries that they would buy from used laptop dealers on eBay. Many of these batteries were still in pretty good shape, some with even 67% capacity left in them. They experimented with about 500 to 600 batteries and successfully built their first prototype.

They started Nunam, which in Sanskrit means 'for the future', in 2018. The company has gone on to become one of the most sought-after startups in the space, and Audi is supporting a number of pilot projects.

“We are helping owners of batteries to optimise their battery asset across the life cycle,” says Chatterjee.

“If you own a lithium-ion battery in a commercial EV like an e-rickshaw, you will see that after four years the range goes down significantly, because these types of vehicles are running extensively every day. On recycling these batteries today, the residual value that you get is very low, maybe 2-3% of the battery asset value, which is not very attractive to an owner. With reuse, the goal here is to enable owners to earn more than just recycling, which is key in optimising their total cost of operations of the battery,” he explains.

Recycling means batteries are crushed and the raw materials are extracted to make new battery cells. Nunam's work begins before recycling gets underway.

"We work with strategic partners, who take out the battery packs at the source and deliver them to us. We first understand whether the battery can be reused or not." 

Its proprietary technology helps understand how good these batteries are, their condition, and how long they would last in a second life scenario. The used batteries are then turned into Nunam’s stationary energy storage systems.

“We are reusing these batteries by making our own battery packs consisting of used cells, and that is really used for stationary storage. We don't put them back in mobility. We use them only for stationary purposes like solar or UPS (uninterruptible power source) applications,” adds Chatterjee.

Audi-Supported Pilots

Over the last four years, Nunam has also been working closely with the Audi Environmental Foundation building a range of prototypes and pilots.

“Audi Environmental Foundation has been supporting us from the very beginning. They’re a really great partner,” says Chatterjee.

For one of the first pilots, they worked with the Selco Foundation, who have been focusing only on solar-based applications for over two decades.

"They had been running an initiative to provide solar-based LED lighting to fruit and vegetable vendors, who needed to illuminate their products in the markets in the evenings. Previously, they had an energy entrepreneur like a small-scale grocer or a ‘kirana’ shop with a solar panel, who would charge batteries using solar power during the day, renting out the batteries to these fruit and vegetable vendors in the evening, who would return them back in the morning."

The Audi Environmental Foundation supported Nunam to develop these second-life systems using laptop batteries. It developed 20 prototypes of these portable systems, which can be held in your hands, can power an LED light, and are capable of USB charging.

The Foundation also helped the team get its hands on Audi e-tron batteries from their prototype vehicles. In stark contrast to laptop batteries, EV batteries are on the premium side, so their life cycle is very different. 

"We were able to do much more complex stuff. We built two prototypes, one which was a 5kWh system with an organisation called The Energy and Resources Institute (TERI), a Delhi-based institute focusing on renewable energy. TERI had a solar nano-grid in a village near Lucknow. Our battery along with the solar power was helping illuminate 40-50 shops on small rural roads."

The team has worked with another NGO called SVYM in Mysore, Karnataka, where they deployed a similar system for a women self-help group. This group created textile products, but their sewing machines were inoperable during power cuts. Nunam's system provided them with the energy backup to work uninterruptedly, allowing them to double their revenues.

"We’ve been able to run pilots on environmental technology that have a visible impact. We are doing a new project with them (Audi), where we are implementing their batteries into an e-rickshaw application,” he continues.

Rolling Out Second Life Battery Products

Battery reuse is still in very nascent stages. Chatterjee, however, is optimistic about what the future holds.

“Our goal is to be the player helping optimise the battery across the life cycle with the technologies and solutions that we are providing. This year, our focus is to go for initial commercial traction with strategic partnerships and different models, both on our product side, as well as the partnerships we have on the battery ecosystem and OEM side," he says.

"This year is more about setting the right partnerships and the first roll-out of our commercial products - our second-life battery products and some of the other services that we offer for battery life cycle optimisation. We know that this is a long-term game, and we’re looking to achieve high growth over the long term. This year is about setting the right baseline from a commercial and from a partnership point of view, and we can grow from there,” concludes Chatterjee.