Smart Battery Management: Driving Hybrid Vehicle Efficiency in India

Shamal V P, Practice Head – Electrification & Vehicle System Engineering at Tata Elxsi, engages in a conversation with Industry Outlook, discusses how AI-driven algorithms integrated into Battery Management Systems (BMS) are enhancing the efficiency, safety, and adaptability of hybrid vehicles in India. The discussion sheds light on innovations such as digital twins, edge computing, advanced thermal management, and modular BMS architecture, while also addressing key concerns like cost optimization, localized material sourcing, and cybersecurity. Shamal brings over two decades of experience in embedded product design, with deep expertise in model-based design, system engineering, electric and autonomous vehicle integration, and embedded software development. Let’s hear it from his lens.

With the growing adoption of hybrid vehicles in India, how is the integration of AI-driven algorithms in Battery Management Systems (BMS) enhancing efficiency and performance?

The Battery Management System (BMS), whether used in hybrids or fully electric vehicles, is fairly complex. Looking at hybrids, there are different types—micro, mild, plug-in, and series hybrids. Currently, in India, it's mostly mild hybrids. We have yet to get into plug-in or series hybrids. Still, the BMS is quite complex. Many algorithms are involved in estimating the remaining charge, the battery’s remaining useful life, predicting anomalies, thermal runaways, and other aspects. These estimations depend on internal and external factors such as temperature, cell characteristics, driving behavior, terrain conditions, and more.

While empirical or mathematical models can define these algorithms, they are extremely complex. That’s why, for most applications today, we are creating models to estimate, predict failures, and determine when battery maintenance is being carried out. This is done using digital twins of the battery, deployed on the cloud. These models consider various influencing factors and provide more accurate predictions. Some algorithms may need to be deployed within the vehicle itself. Furthermore, edge concepts are becoming popular in BMS, enabling critical decision-making near the battery pack. Other aspects are managed on the cloud for better prediction.

Another aspect is vehicle behavior, given India’s diverse climatic conditions and geographical demographics — deserts, coastal areas, mid-regions, and hilly terrains. Vehicles operating in different regions should be fine-tuned. This is also where digital twin models can play a vital role by fine-tuning battery parameters to deliver optimal performance under different operational conditions.

Thermal management technologies have become crucial for hybrid vehicle battery safety. How are automakers in India adopting new solutions to address this challenge?

Thermal management is a critical factor in the BMS and battery pack design. It plays an important role mainly due to the safety aspect. If the battery pack temperature increases, it can lead to thermal runaways, which could result in fire. But this is not the only aspect. Thermal management also improves efficiency and extends battery life. Batteries are supposed to operate within a specific temperature range—neither too cold nor too hot. If we maintain this range during charging and discharging, battery life increases. For faster charging and reduced charging time, a good thermal management system is essential.

Currently, one aspect of thermal management where extensive changes are happening is in sensing. More accurate, smart sensors are being considered for accurately measuring and thereby predicting the thermal behavior of the battery. Virtual sensors are also being explored using AI models, so that the number of physical sensors can be reduced without compromising on accuracy and performance. Uniform temperature distribution is important to avoid hotspots and should be addressed during the design phase itself. Advanced simulations help identify hotspots and guide thermal strategies using cooling channels or increased coolant flow. Immersive cooling using dielectrics is also being explored. Gas and Pressure sensors are now getting integrated in battery packs to predict thermal runaways. Larger surface area cells, like blade cells, are being considered for better heat removal. These are some of the concepts OEMs in India are exploring.

Balancing high-performance BMS with cost considerations remains a key challenge. How are Indian manufacturers ensuring affordability without compromising technology?

BMS for plug-in hybrids and battery electric vehicles, the packs are very big, with tens of kilowatt-hour capability. The major cost contributing factor is the cell, more than the BMS. So, the focus for plug-in hybrids and battery electric vehicles is to optimize the battery or cell cost. If you compare the BMS and battery cost, the battery is the major contributor. In mild hybrids, the battery pack is very small—2 or 3 kilowatt-hours. The BMS cost remains the same, making it a major cost component. One aspect is that a high-performance BMS helps get more out of the same pack, like extending a 2kWh battery range from 20 to 25 or 30 km, thus reducing battery size and cost.

Another important aspect would be to reduce the BMS cost itself. OEMs are creating modular, scalable BMS architectures to reuse across vehicle types and chemistries, so as to reduce per-unit development costs. Smart sensor costs are dropping, enabling partial BMS processing within the sensor, while the remaining functions go into a shared control unit. Hybrid control units now integrate BMS functions. Also, with connected vehicles, complex BMS features are being deployed on the cloud, thereby reducing the need for expensive onboard controllers.

Sourcing critical materials like lithium and cobalt locally is becoming more strategic. How does this impact the development and cost of BMS in India’s hybrid vehicle sector?

When we speak of cell sourcing and critical materials on the cell side, battery cells used in India mostly come from imports. However, more tie-ups are happening in cell manufacturing today. Through these tie-ups, sourcing of critical materials is also happening as part of the Make in India campaign. Furthermore, the government is also investing to leverage natural resources and explore new chemistries like sodium-ion, aluminum-air, etc., to become self-sufficient. Recycling of used batteries to extract the rare materials will be gaining momentum in India in the coming years. Battery Passport or Battery Aadhaar is becoming mandatory in India to track cells throughout their lifecycle, from manufacturing to recycling, thereby ensuring effective tracking of critical materials.

OEMs are responsible for implementing Battery Aadhaar to extend battery applications in second and third life and enable recycling. On the BMS side, the key is to address different battery chemistries. The BMS needs to be made chemistry-agnostic so that newer chemistries can use the same BMS, which is a key development focus.

As hybrid vehicle BMS complexity increases, how are Indian manufacturers addressing the growing cybersecurity risks linked to data connectivity and system integrity?

Cybersecurity risks are not specific to BMS, but rather apply to all connected vehicles, whether hybrid or conventional internal combustion engine vehicles. As wireless BMS technologies emerge, cybersecurity concerns remain. OEMs must address these risks holistically, ensuring that the entire lifecycle, from design to operation, complies with cybersecurity standards. Most OEMs now partner with companies like Tata Elxsi, which are certified for developing cybersecurity-compliant solutions. We adhere to standards such as ISO 21434 and UNECE regulatory standards, which are expected to be adopted by Indian OEMs as well. Here, critical measures include encrypted end-to-end communication, secure software updates, and rigorous testing using advanced AI models for penetration testing.

Innovations in BMS technology are key to enhancing energy efficiency and battery lifespan; what advancements are expected to shape India’s hybrid vehicle market in the next decade?

Innovations in Battery Management System (BMS) technology will be the driving force of hybrid vehicles in India. The market is now oriented towards mild hybrids, but plug-ins and series hybrids are likely to gain market share. Series hybrids which rely on using motors only and not the internal combustion engines are also demanding larger battery packs than the mild hybrids. Therefore, the BMS solutions must be modular and scalable in order to manage different types of batteries within different hybrid segments.

Also to note, connected features and digital twins are playing a critical role. Digital twins of batteries will be deployed for each vehicle, ensuring efficient battery use, longer life, and enabling prognostic activities. Edge AI is also becoming integral, with critical BMS functions being processed within the vehicle, enhancing real-time decision-making. Another emerging trend is the combination of batteries and super capacitors. Super capacitors can absorb energy quickly, especially during regenerative braking, and release it to charge the battery more slowly, a concept expected to become popular in hybrid applications.

The shift towards software-defined architecture is another key trend. BMS functions will be distributed across sensors, controllers, and high-performance computing platforms, allowing for runtime calibration and optimization to adapt to varying driving behaviors and terrain conditions, ensuring optimal performance.