What is an Active Balancer Module?

An Active Balancer Module (Active Balancer) is a unit which will “Actively” balance the voltage between 2 or more cells connected in series.  When charging/discharging cells connected in series, each cell will behave differently depending on their internal resistance which will result in the being unbalanced.  The more you charge/discharge the battery bank, the State of Charge (SOC) and voltage variance between the cells will increase, resulting in 1 cell having a greater SOC, while another cell within the same bank having a lower SOC.  The problem with this is the potential for the cell with the higher SOC being overcharged, while the cell with the lower SOC being over discharged and therefore those cells experiencing a greater derogation in comparison to the other cells.

An Active Balancer will monitor and transfer current between cells within a bank.  Cells with a higher SOC, to cells with a lower SOC ensuring they are better balanced and illuminate the chance of one particular cell in the bank being over charged/discharged.

Unlike a passive balancer, an active balancer will operate while a battery bank is being charged, discharged or even left in storage.

October 21, 2022 — Ernest Brindley