SUN Mobility Aims To Change The Way People Commute

SUN Mobility Aims To Change The Way People Commute

Interaction SUN Mobility Change Commute

Seven months after announcing an association with commercial vehicle maker Ashok Leyland, SUN Mobility – a 50:50 joint venture between Virya Mobility 5.0 and SUN New Energy Systems – has demonstrated how swappable batteries could be one of the faster and cost-efficient routes to meet India’s all-electric mobility aspiration. At the just-concluded Auto Expo, Ashok Leyland unveiled its ‘Circuit-S’ electric bus powered by SUN Mobility’s swappable smart battery.

Many in the industry have viewed this as a pioneering approach in India’s EV journey, while there are others who have expressed reservations about its mass market success potential. To get to the core of the idea, we caught up with Chetan Maini, Co-founder and Vice Chairman, SUN Mobility.

Swappable battery is a concept whose time has come, believes Maini. That said it isn’t yet ready for blanket implementation. SUN Mobility’s idea was to create open architecture solutions that could fit into two-wheelers going up to large buses. The solution especially is apt for shared mobility services, said Maini, who in 2001 had founded Reva as the country’s first electric car. A school bus or a private vehicle that commutes a total of approximately 60-70 km a day wouldn’t need swappable batteries, but in a shared mobility scenario, where the number and length of trips aren’t exactly defined, swappable batteries would be a boon.


SUN Mobility has used lithium-ion based batteries that are compact, powerful, lightweight and have very long life. Together with its smart battery management system, Maini claimed, the company has offered a solution with the right balance. On the Circuit-S bus, for instance, the smart battery is 1/4th the weight of a regular li-ion battery. Moreover, swapping takes less time as compared to conventional fuelling of an IC-engine vehicle. Although the claimed time for swapping of batteries on the Circuit-S is four minutes, the demonstration at the expo was completed in approximately two and half minutes.

Convenience and quick recharging options aside, the smart battery could also potentially have a huge impact on the cost of running a vehicle. Electric buses are very expensive at this stage, and that’s largely because of the cost and size of the batteries they have to carry. A typical bus that travels the whole day runs on a three-tonne battery. With smaller and swappable batteries, it can potentially run with a 500 or 600 kg battery – thus saving 2.5 tonne of battery weight.

That’s an area SUN Mobility has clearly addressed – lesser weight carried around means lower cost of operation, even as powertrains and the whole system gets more efficient. The current battery solution is compatible to 9-12 m buses, and “very soon”, the company is expected to roll out similar solutions across different vehicle platforms.

Swappable batteries have another distinct advantage. As these batteries are checked and managed every day, an operator can have a very high uptime. This is extremely critical for fleets as a higher uptime directly results in higher revenue/km. The challenge, however, is to have the vehicle deliver the same performance at similar price points. Once that happens, consumers will start seeing electric mobility as a real viable solution. That’s what SUN Mobility is trying to do by enabling the industry – across platforms, agnostic to OEMs and providers – to really help the ecosystem.

From a battery chemistry perspective, SUN Mobility is completely agnostic. Should any new battery chemistry be more viable than the current li-ion chemistry it works on, the company will give it due consideration. While certain li-ion chemistries offer the right life, cost, balance and weight, that may change in the future, and Maini is mindful of that.


The Government of India’s 2030 “all-electric” mandate is a good aggressive target, and even an achievement of 60-70 % of that target by that time would be considered a good success, he opined. The key is in being able to offer solutions that are cost-competitive. EVs should work if the industry is able to give customers more than what they have today. Having said that, there can’t be a “one-size-fits-all” strategy to address the mass market, said Maini. “We might adopt a similar concept, but solutions will have to be different,” he noted.

One segment of vehicles is likely to move very fast towards electric mobility. Maini was referring to shared mobility – be they three-wheelers, four-wheelers or buses. That would be the start, and over time, the industry will move to personal mobility, he said. SUN Mobility is lining up a few more launches in the near future across different platforms and vehicle types.


For now – in the first phase – the Bangalore-based company will import the li-ion cells, and manufacture the packs in India. Some parts of the battery management system (BMS) are being done by SUN Mobility in-house, while some others are being done with partners. In years to come, the company is keen to work on offering other mobility solutions, but it will not do vehicles.

“I want to enable the ecosystem in an open way. That’s what the country needs. That’s what a company like ours – with our expertise – would like to do. Product development cycles are long, and here we’ve developed a solution working and running in seven months. That’s the kind of innovation we can bring up. We need to help create an ecosystem to further growth in electromobility,” said Maini. Clearly, that’s the need of the hour.

TEXT: Deepangshu Dev Sarmah