Cellebalancering

Cellebalancering, often translated as cell balancing, is a crucial process in battery management systems (BMS), particularly for lithium-ion battery packs composed of multiple individual cells. The primary goal of cell balancing is to ensure that all cells within a battery pack have a similar state of charge (SoC). This is important because variations in SoC between cells can lead to several issues.

During charging, if some cells reach their maximum voltage limit before others, they will be prevented from receiving further charge, even if other cells in the pack are not fully charged. This underutilizes the pack's capacity. Conversely, during discharge, weaker cells may reach their minimum voltage limit earlier, leading to premature shutdown of the entire pack, again reducing usable capacity.

Cell balancing aims to mitigate these disparities. There are two main types of cell balancing: passive and active. Passive balancing dissipates excess energy from higher charged cells as heat, typically through resistors, until their SoC matches that of the lower charged cells. Active balancing, on the other hand, redistributes energy from higher charged cells to lower charged cells using components like capacitors or inductors, thereby improving overall energy efficiency.

By maintaining a consistent SoC across all cells, cell balancing extends the lifespan of the battery pack, enhances its performance by maximizing usable capacity, and improves safety by preventing overcharging or over-discharging of individual cells. This process is vital for applications where battery performance and longevity are critical, such as electric vehicles, portable electronics, and energy storage systems.