Active cell balancing for a 2s Lithium ion battery pack using flyback converter and push-pull converter

Abstract

The usage of Lithium ion (Li-ion) batteries has been increasing day by day due to environmental concerns. One of the major applications in which Li-ion batteries are used is electric vehicles (EVs). Li-ion batteries are highly sensitive to over-voltage, under-voltage and temperature conditions unlike other batteries. Li-ion batteries need real-time monitoring and a battery management system (BMS) is used for this purpose. This paper talks about active cell balancing schemes using transformer switching. Active cell balancing is done to balance the imbalances created in the battery pack to maintain a constant state of charge (SOC). A comparative study on pack-to- cell configurations of active cell balancing using switched transformer method is done to draw conclusions.

Battery Dynamic Balancing Method Based on Calculation of Cell Voltage Reference Value

“…Active balancing methods are considered to be the most effective. The most common active balancing systems are built on the basis of transformers, inductive or capacitive voltage converters, with energy transmission into one common storage (Figure 2a) or into one cell (Figure 2b) [22,26,42]. This provides highly efficient battery balancing without forced dissipation of excess GC charge in the form of heat on ballast resistance [43,44].…”