Deep Dive: Ola Electric 2W Battery Teardown & Future Performance Needs

A comprehensive teardown of the Ola Electric two-wheeler battery pack, offers a detailed look at the engineering and design choices that underpin Ola's cost-driven strategy in the electric scooter market. This analysis not only dissects the current design but also highlights critical areas for future evolution.

1. Introduction

Ola Electric has rapidly emerged as a key player in India's EV sector, basing its growth on vertical integration and in-house battery technology. The foundation of the current battery pack design, including its unique "banana-shaped" enclosure, traces back to the IP and design ideas acquired from the European startup Etergo EV in 2020, signaling how strategic acquisitions accelerated Ola’s product roadmap.

2. Pack Fundamentals

The pack is built around 224 LG 21700 NMC cylindrical cells, each rated at approximately 4.8 Ah. These cells are configured in a 14-series by 16-parallel (14S16P) arrangement, yielding a nominal pack voltage of about 51.8 V and an overall energy capacity of approximately 3.9–4.0 kWh. The custom-molded plastic enclosure is specifically designed to fit the scooter’s underfloor cavity, maximizing space and keeping the center of gravity low.

3. Module Architecture

The 224-cell array is internally divided into two modules. The pack achieves its 14S configuration by connecting these two modules in series. Each module is further split into two halves with different series/parallel arrangements, utilizing a mirrored modular structure to simplify interconnections and ensure compact routing. All cells are uniformly oriented, allowing for consistent application of Thermal Interface Material (TIM) across the base for heat extraction.

5. PCBs Inside Each Module

Each of the two main modules features its own network of Printed Circuit Boards (PCBs). Slim PCBs run along the sides of the modules to handle voltage measurement and interconnections at the cell group level. A smaller central PCB is dedicated primarily to thermal monitoring, hosting various temperature sensing points. A wiring harness links these PCB's to consolidate data signals before routing them to the main Battery Management System (BMS).

6. Thermal Management

Ola employs a passive cooling system, a key indicator of its cost-control philosophy. Instead of heavy or complex liquid cooling, the design relies on:

• Thermally Conductive Polymer : Specially engineered plastic cell holders transfer heat more effectively out of the module.

• TIMs : Used to ensure efficient heat transfer between the cell bed and the enclosure.

• Air-Cooling Fins : Located on the outer housing to increase surface area and improve natural heat dissipation during operation.

This system is sufficient for urban commuting but is not designed for sustained high-power discharge rates, limiting the pack's performance in aggressive use cases or prolonged operation in extreme heat. To mitigate this, a key future requirement could be the integration of a semi-active cooling system (such as fan-assisted heat extraction) to better manage cell temperatures and prevent performance throttling.

7. BMS & Electronics

The Battery Management System (BMS) is a compact, consolidated board responsible for all critical safety and control functions. It features:

• Direct Busbar Connections : Two high-voltage busbars bolt directly to the PCB.

• MOSFET's : Used as switching elements for charge/discharge control and safety protection.

• Passive Cell Balancing : Achieved using linear resistor banks (bleed resistors), which is an economical method.

• Microcontroller : Coordinates voltage monitoring, current protection, and vehicle communication.

8. Safety & Enclosure Design

The pack prioritizes lightweighting and manufacturability through its use of a plastic enclosure and custom plastic cell holders. Ingress protection is managed by seals and nylon cable glands where the cables exit the pack, contributing to a robust water- and dust-resistance rating (IP67 or higher). The insulation strategy utilizes selective plastic cutouts and barriers to tightly control electrical pathways and minimize the risk of shorts.

While efficient for production, the plastic enclosure compromises overall crash robustness. An improved design could incorporate a hybrid structure (e.g., a structural aluminum baseplate) or internal energy-absorbing foam/honeycomb to better protect cells from severe impacts without excessive weight gain, enhancing overall vehicle safety.

9. Observations & Insights

The overall design reflects a clear focus on cost efficiency and scalable manufacturing. The combination of aluminum busbars, ultrasonic wire bonding, and a plastic housing streamlines assembly while minimizing weight. The mirrored module architecture is production-friendly.

However, the ultrasonic bonding and heavy sealing, while efficient for initial assembly, severely limit serviceability. The next-generation design should consider more modular, bolt-on components (especially for the BMS) and easier-to-open seals to reduce complex repair costs and vehicle downtime for consumers.

10. Conclusion

Ola Electric has achieved a battery pack design that perfectly reflects its market strategy delivering high energy density and a lightweight footprint at a low cost. While the modularity and manufacturing efficiency are strong points, the compromises—such as the reliance on passive cooling and a primarily plastic enclosure—limit the thermal headroom for sustained high-power use and reduce long-term serviceability and crash robustness compared to premium alternatives.

The pack is a strong engineering solution for democratizing EV adoption at scale in the mass market. Looking ahead, the challenge for Ola will be to evolve this design, balancing its core strength of cost leadership with enhanced thermal durability, superior crash protection, and reduced long-term maintenance costs for the consumer, paving the way for an even more robust and competitive product.