BMS e bike guide for 2025 riders
27,Aug 2025
In the rapidly growing Indian electric vehicle (EV) and energy storage market, the battery management system (BMS) serves as the "brain" of lithium-ion batteries, ensuring safety, efficiency, and longevity. Among its core functions, cell balancing stands out as a technology that directly impacts battery performance—especially in India’s extreme temperatures (45°C+ in summer). This article compares the two primary balancing methods: passive balancing and active balancing, with a focus on their applicability in Indian scenarios.
Figure 1: A modern BMS module with green cylindrical cells and circuit board, commonly used in Indian EVs.
Working Principle
Passive balancing, also known as "lossy balancing," uses resistors to dissipate excess energy from overcharged cells as heat, bringing all cells to the same voltage level. This method follows the "bucket principle," where the lowest cell capacity determines the entire pack’s performance .
Working Principle
Active balancing transfers excess energy from high-voltage cells to low-voltage ones using capacitors, inductors, or transformers—acting as an "energy porter" to optimize pack capacity.
Figure 2: Close-up of a green circuit board showing active balancing components like capacitors and copper traces.
Q1: Which balancing method is better for Indian summer temperatures?
A: Active balancing is superior in 45°C+ conditions. For example, Delhi’s Ola Electric fleet reported 25% longer battery life using active balancing compared to passive systems.
Q2: How much does active balancing cost compared to passive balancing?
A: Active balancing systems cost 30-50% more upfront but reduce long-term maintenance costs by 40% (ION Energy, 2024).
As India accelerates EV adoption and renewable energy integration, selecting the right balancing technology is critical. Passive balancing suits budget-sensitive, small-scale applications, while active balancing is indispensable for high-performance scenarios. With like FAME II subsidies for active balancing BMS, Indian businesses can now invest in long-term battery health without compromising on cost.