Active cell balancing plays a crucial role in extending electric vehicle (EV) battery life by maintaining uniform charge levels across all cells in the battery pack, which maximizes overall battery capacity and prevents premature degradation of weaker cells. This process involves redistributing energy from cells with higher state of charge (SoC) to those with lower SoC, thereby ensuring that no single cell is overcharged or deeply discharged relative to others.
Key ways active cell balancing extends EV battery life:
- Prevents cell degradation: By equalizing the charge among cells, active balancing avoids overstressing individual cells. Cells that are consistently weaker or stronger degrade at different rates, which can cause early failure of the entire battery pack. Balancing keeps all cells operating within their optimal voltage ranges, extending their lifespan and maintaining battery health.
- Improves energy efficiency: Unlike passive balancing, which dissipates excess energy as heat, active balancing transfers energy between cells. This redistribution improves energy efficiency by preserving usable charge within the pack.
- Supports faster and more effective balancing: Active balancing can handle higher balancing currents (up to around 6A), much greater than passive balancing’s typical limit of 0.25A. This allows faster balancing suitable for large-capacity cells and supports systems with fast charge/discharge cycles, crucial for EV operation.
- Facilitates balancing during both charge and discharge: Active balancing can occur while the battery is being charged or discharged, providing more opportunities to maintain balance and extend the runtime of the battery pack. In contrast, passive balancing is generally limited to the charge cycle because it wastes energy during discharge.
- Reduces thermal load: Because active balancing is more energy efficient and does not dissipate excess charge as heat, it reduces thermal stress on the battery, which also helps in prolonging battery life.
In summary, active cell balancing extends EV battery life by ensuring all cells share the load evenly, preventing premature cell aging, increasing energy efficiency, and enabling more rapid and flexible balancing during various operational states. This contributes to safer, longer-lasting, and more reliable EV battery packs.
Original article by NenPower, If reposted, please credit the source: https://nenpower.com/blog/what-role-does-active-cell-balancing-play-in-extending-ev-battery-life/
