With the launch of the Punch EV facelift, Tata Motors has also debuted a new 6-in-1 drivetrain setup, which it claims is the first application of its kind in the country and a major factor behind the lower-than-before retail price of the electric Punch. “The battery non-cell costs have come down, but the 6-in-1 combo drivetrain is certainly cost-effective,” says Anand Kulkarni, vice president, Passenger Electric Vehicles, at Tata Motors.
- New 6-in-1 drivetrain was key in bringing down Punch EV’s price
- It also helped reduce package size by 50 percent and weight by 28 percent
- Efficiency was boosted by 6 percent while also using 40 percent fewer semiconductors
Tata Punch EV 6-in-1 drivetrain explained
For a while now, carmakers, including Tata Motors, have been using 3-in-1 systems that combine the e-motor, reduction gear and DC-to-AC inverter into one unit. However, brands have been integrating more components as part of this x-in-1 approach and developing 5-, 6- and even 10-in-1 systems.
With the new Punch EV, Tata Motors has gone with a 6-in-1 unit that combines the e-motor, reduction gear, inverter, DC-DC converter, PDU (power distribution unit) and on-board charger. With this approach, there are fewer split-up sub-systems and thus fewer connections and independent controllers. Tata Motors says now there’s a 50 percent reduction in package size, a 28 percent reduction in weight, a 6 percent increase in efficiency, a 30 percent reduction in electrical harnesses and connections and a 40 percent reduction in semiconductors.

The reduction in semiconductors and harnesses has helped lower the number of parts and manufacturing costs, and the reduction in weight aids efficiency. The package size reduction is quite easily visible in the Punch EV. One look under the hood, and you see the entire 6-in-1 unit sitting low down with a hollow space above it. Oddly, though, Tata Motors has not deepened the frunk to take advantage of all this space. There are a few other smaller components around, but none that look impossible to move.
X marks the spot
It’s clear then that combined x-in-1 EV drivetrains are the way forward and where Tata Motors and others, too, are headed. However, the number of integrated units will change based on the application requirements. For instance, the upcoming Sierra EV, which is said to have an all-wheel-drive system, would not use two 6-in-1 units on each axle. “It would be an unnecessary redundancy,” says Kulkarni, with on-board chargers integrated into both drive units. “You could perhaps make do with one 6-in-1 unit and maybe a 4- or a 5-in-1 unit at the front,” he explains.
There are, of course, some potential drawbacks with x-in-1 systems. For instance, there’s potential for reduced serviceability and a higher replacement cost if the entire unit needs to be replaced. However, Tata Motors and most system makers say that with reduced components, there are fewer things to go wrong, and this also brings about a reduction in manufacturing complexity, so reliability goes up. Combining systems also brings about reliability because you now have one component maker instead of multiple vendors. “It’s a very robust ecosystem where the integration is so strong, like the handshake between components (the way systems communicate with others), too, gets simpler and more reliable,” adds Kulkarni.
Would Tata Motors go beyond a 6-in-1 integration? Kulkarni replies, “We could look at integrating the electrical compressor because this is also running on the high voltage”, indicating that the brand could go for higher module integration. The combined drivetrain could then expand to take on associated ancillaries as well.
























