Vehicle lightweighting is not just about the weight, says Tata Motors' Anand Kulkarni

Despite the substantial benefits to be derived from the use of lighter materials for making cars and other vehicles, manufacturers often have to compromise on this front due to considerations such as supply chain risks and cost, said Anand Kulkarni, Chief Products Officer, Head of HV Programs and Customer Service, Tata Passenger Electric Mobility Ltd.

Traditionally, manufacturers have always opted for lighter and lighter materials as they increase the fuel efficiency of the vehicle. However, this has become a tough balancing act, Kulkarni said during a panel discussion organised by Autocar Professional on vehicle lightweighting.

"As a development team, you would want to use fewer materials that are not easily available, as then you may be open to supply-side challenges in the future," he pointed out.

This balancing act extends beyond steel, aluminum, or composites, among others. Automakers, for instance, are also required to consider factors like paint compatibility when switching to different materials like aluminum, he explained.

The key, according to Kulkarni, lies in careful implementation. "The most plausible solution has to be taken," he added while revealing the flow chart of how decisions are taken in an OEM with regard to material sourcing and manufacturing. The top executive opines that while scientific knowledge and solutions for various lightweighting technologies are already available, the real challenge lies in putting them into practice while keeping an eye on supply-side constraints or challenges.

In the context of the lightweighting exercise of Tata Motors’ hugely popular Punch EV platform, Kulkarni explained that the battery design of the car contributes to overall robustness, allowing for a lighter structure. 

This eliminates the need for complex wheel displacement control, leading to a smoother ride. This platform exemplifies the successful balancing act achieved through innovative architecture, he said. "The advanced materials allow the experimentation of complex geometries within the constraints of vehicles."

For EVs, Kulkarni explains, the safety aspect during side impacts remains more stringent. EV battery packs require exceptional strength. Adding metal fortifies them, but this increases their weight. Therefore, the goal is to develop lightweight yet damage-resistant materials, thereby highlighting the complexities of decision-making in EV design. " The pursuit of lightweighting is to have safer and more durable materials," Kulkarni remarks during the discussion.

According to Kulkarni, the concept of lightweighting has been around for a long time. Traditionally, it meant needing less fuel for heavier vehicles.  Over time, engineers have developed lighter yet stronger and more robust vehicles. This is an ongoing process, and the goal remains the same: to create efficient and safe vehicles. Generations of engineers have tirelessly pursued this objective, he further emphasised.