Tata Motors, a leading EV maker in India, started its green journey with the Nexon EV, which was based on the conversion approach. The ICE Nexon was already available, and what Tata did was convert that ICE into an EV by featuring an electric motor, a suitable battery, and other EV-specific components and design updates. Now, Tata Motors has elevated its EV game by introducing ground-up EVs based on the dedicated platform. The latest in Tata’s lineup is Harrier.ev. Anand Kulkarni, Chief Product Officer, Tata Passenger Electric Mobility, discussed the aspects of Harrier.ev, its platform and other latest tech with Zee News’ Lakshya Rana in an exclusive interview. Excerpts:
Q: What is Acti.ev plus platform?
A: When it comes to developing electric vehicles, there are two primary approaches. The first is to start with an existing vehicle and build the battery and electric systems around it. The second approach is to first design the battery and then build the vehicle around that.
Why these two approaches? The first method, a “conversion approach,” allows for a quicker time to market because the base vehicle is already available. This was our strategy in the first generation of the Nexon EV. It’s a credible way to electrify a car, but it may not be the most optimized in every aspect, as there is still a great deal of efficiency that can be gained.
Once we established ourselves as category leaders in the EV segment, selling more cars than our competitors, we decided to build more choices and make our vehicles more efficient and highly optimized. To achieve this, we needed to create a platform that would allow us to design the car around a higher-capacity battery from the ground up. This new architecture is what we call acti.ev.
Our first three cars – the Nexon EV, Tiago EV, and Tigor EV – were all based on the conversion approach. However, we laid the foundation for the acti.ev architecture during the COVID-19 pandemic. We introduced it for the first time on the Punch EV in January 2024. We decided to define Acti.ev as a “Born EV” platform.
When we conceptualized the Acti.ev architecture, we defined it by a few key characteristics:
Flexibility: It must be adaptable to multiple vehicle types.
Scalability: It must be scalable for different sizes and segments.
Agnosticism: It must be agnostic to battery cell format and chemistry, allowing for various battery types.
Versatility: It needs to accommodate different drivetrain and suspension arrangements.
This is a four-layer architecture:
Powertrain: Includes the battery, motor, and drive arrangement.
Chassis: The vehicle’s foundational structure.
E&E (Electrical and Electronics): The crucial digital architecture.
Cloud: For data sharing and connectivity.
The second vehicle developed on the Acti.ev architecture was the Curvv.ev. Now, the Harrier EV is an evolution of this platform, which is why we call it the Acti.ev Plus. The “Plus” signifies several key enhancements: a dual-motor setup for quad-wheel drive, a larger frunk, and a high-voltage, centrally stacked battery architecture designed for high capacity.
Q: What is TiDAL and how does it benefit Harrier.ev?
A: TiDAL stands for Tata Intelligent Digital Architecture Layer. It is our version of a software-defined vehicle (SDV). SDVs are becoming mainstream because modern cars have a huge number of sensors, radars, and cameras. This car (Harrier.ev) alone has 23 sensors, 9 cameras, multiple radars and proximity sensors.
In the past, all of these were connected by extensive wiring, which created problems with integration, weight, and internal space. With a software-defined architecture like TiDAL, we use a CAN-based system to connect these devices, consolidating many control units into intelligent domain controllers. This allows us to:
— Introduce over-the-air (OTA) updates without needing a service station visit.
— Prioritize software over hardware, making the vehicle’s functions highly configurable.
— Fix bugs and improve systems remotely.
— Add new functionalities later, keeping the car’s value fresh and updated over its lifetime.
This is our first version of the TiDAL architecture, and it will continue to evolve.
Q: Shed some light on the battery technology used in the Harrier EV.
A: We were the first to use Lithium Iron Phosphate (LFP) batteries, and we continue to do so because they are ideal for India. LFP batteries are chemically very stable, which is crucial for our high temperatures. They also offer a great balance between performance and cost, which is essential for the Indian market.
The Harrier EV features a high-voltage LFP battery with liquid cooling and improved charging technology. The charging rate has been enhanced to 1.5 C, almost double that of our first Nexon EV (0.7 C), allowing the car to charge from 10% to 80% in just 30 minutes. This is a significant advantage for a car with a usable range of over 475 km. To build customer confidence, we are also offering a lifetime warranty on the batteries.
Q: How did you bring the quad-wheel-drive setup to the Harrier EV, and what were the challenges?
A: A quad-wheel-drive system requires two motors, one in the front and one in the rear. To integrate this, we had to completely redesign the rear suspension, moving to a sophisticated four-link setup. This was a significant challenge, as developing suspensions takes a long time and requires extensive testing for durability, performance, and comfort.
We also had to manage the increased mass of the car due to the batteries. The Harrier EV’s mass has gone up by about 300-350 kilograms. This required us to strengthen the car’s crash structure to achieve a 5-star BNCAP safety rating. We also had to ensure the suspension was tuned perfectly to prevent a bouncy or sluggish feel, striking a balance between comfort and stability.
We need to have suspensions that are soft vertically but stiff laterally. If you have a rubber, you can make the rubber soft in one direction, but that always makes the rubber soft in the other direction also. So, that is the challenge that our engineers have solved to make the car very compliant in the longitudinal and fore-aft direction, which gives you excellent levels of bounds but also makes it so stiff in the side direction that it does not give you that nauseating feel or anything. And that is the beauty of this ultra glide suspension.
Q: What are the challenges with Level 3 ADAS in India?
A: The challenge with Level 3 ADAS is not capability but liability. Level 3 systems transfer control to the vehicle, and the legal framework for who is responsible in the event of an accident is not yet defined. Is it the driver, the manufacturer, or the car itself? The lack of clarity on liability and the highly variable infrastructure on Indian roads (missing markers, inconsistent road widths) means it will take more time for Level 3 ADAS to be introduced in the Indian market.
Even today, there are systems that are capable of doing completely hands-free, but nobody calls it a level 3 because the moment you call it level 3, you get into a completely different territory.
Leave a Reply