A battery balancing circuit is a fundamental component within a Battery Management System (BMS). Its primary function is to maintain an equal voltage level across all individual battery cells connected in series. Due to manufacturing variances, chemical cells naturally exhibit minor differences in internal resistance, capacity, and self-discharge rates. Without a dedicated balancing mechanism, the weakest cell in a pack will charge and discharge faster than the others, leading to premature capacity loss, accelerated aging, or severe safety hazards like thermal runaway.
