Linear programming based design and analysis of battery pack balancing topologies

High voltage Li-ion battery packs are typically configured in a modular fashion. In this paper, the performance of different battery pack balancing topologies is analysed at both module and cell levels. Two-level balancing topologies, including cell-to-cell balancing at intra-module level and module-to-module balancing at inter-module level, are considered in the analysis. Topologies are comprised of combinations of line shunting, ring shunting, synchronous fly-back, multi-winding, and dissipative shunting. Aspects of battery pack balancing performance, such as minimum balancing time, minimum plug-in charge time, and minimal energy loss in balancing are calculated using linear programming. Component counts of every balancing topology for the entire battery pack are also compared to assess circuit complexity.