Sun Mobility t3-55T electric trucks with world’s first modular battery swapping at Pravaas 5.0

Bengaluru-based battery swapping company Sun Mobility is making its biggest push yet into India’s commercial electric vehicle market with the launch of what it describes as the world’s first modular battery swapping platform for electric trucks and buses across the 3-tonne to 55-tonne segment. The company is planning to showcase the product which has been developed and demonstrated with the Tata Motors’ Starbus 12m EV.

Backed by a $78 million (about ₹650 crore) investment through its IndoFast Swap Energy joint venture with Indian Oil Corporation Ltd (IOCL), the platform marks the company’s entry into the heavy commercial vehicle market after establishing its battery swapping technology in two- and three-wheelers. It will make its public debut at Pravaas 5.0 in Gandhinagar from July 9 to 11.

If adopted by multiple manufacturers, the OEM-agnostic battery architecture could create a common energy infrastructure for commercial electric vehicles, replacing proprietary battery ecosystems with a shared swapping network.

“We are not accelerating the transition to electric mobility. We are eliminating the barriers that slowed it down with the world’s first modular multi-battery swapping technology,” said Chetan Maini, Co-Founder and Chairman of Sun Mobility, ahead of the launch.

The platform received AIS-038 certification from the Automotive Research Association of India (ARAI) in March, becoming the first indigenously developed high-voltage swappable battery platform for trucks and buses to secure this approval. The certification validates its thermal, electrical and mechanical safety standards, clearing a key regulatory milestone for commercial deployment.

Designed for vehicles ranging from 3-tonne light commercial vehicles to 55-tonne multi-axle tractor-trailers and intercity buses, the platform supports both 330-volt and 660-volt electrical architectures. It uses modular 50 kWh and 100 kWh battery packs that can be automatically swapped in under three minutes.

Sun Mobility is targeting one of the biggest hurdles to commercial vehicle electrification: battery economics.

Electric buses and trucks typically use fixed battery packs of 200-400 kWh, increasing vehicle acquisition costs while reducing payload because of battery weight. Charging these vehicles can take between 90 minutes and four hours, lowering fleet utilisation for operators whose revenues depend on keeping vehicles on the road.

The opportunity is significant because private operators own nearly 90 per cent of India’s commercial buses and trucks, making operating economics and vehicle uptime critical to EV adoption.

Sun Mobility’s strategy mirrors a battery swapping model that has gained significant traction in China, now the world’s largest market for electric commercial vehicles.

Sun Mobility’s Battery-as-a-Service (BaaS) model separates battery ownership from the vehicle. Fleet operators purchase the vehicle while paying only for the energy consumed. According to the company, the model reduces the upfront acquisition cost of an electric bus or truck by about 40 per cent, bringing prices closer to comparable diesel and CNG vehicles. Operators can also optimise payload by carrying only the battery modules required for a particular route instead of oversized fixed battery packs.

Commercial deployment will be led by IndoFast Swap Energy, the company’s joint venture with IOCL, which will establish automated battery swapping stations across IndianOil’s fuel retail network, while Sun Mobility supplies the battery technology, swapping systems and manufacturing.