Abstract—This paper presents a theoretical analysis of the advantages of active charge balancing in lithium-ion battery systems and a comparison to passive balancing solutions.
Universal equations to estimate the benefits of an actively balanced battery system concerning energy savings and lifetime extension are derived from basic statistics. The calculations depend only on the configuration and aging properties of the individual cells. Their validity is limited to applications with full cycle usage and cells whose capacity values are normally distributed. The losses due to passive balancing in an nSmP battery system are calculated as well as the overall energy savings when applying active balancing. Furthermore, the extension factor for the lifetime of an actively balanced battery system is found to be in a range between 1.23 and 1.02 depending on the system configuration and the cell parameter. Based on the results, several options are identified to increase the energy efficiency of conventional passive balancing systems.
Index Terms—Active battery management system, active balancing, lithium-ion battery charging.
The authors are with the Institute for Energy Systems and Fluid Engineering, School of Engineering, Zurich University of Applied Sciences, CH-8400 Winterthur, Switzerland (e-mail: manuel.raeber@zhaw.ch, andreas.heinzelmann@zhaw.ch, adrian.taeschler@zhaw.ch).
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Cite:M. Raeber, A. Heinzelmann, and A. Taeschler, "Beneficial Effects of Active Charge Balancing in Lithium-Ion Battery Systems," Journal of Clean Energy Technologies vol. 4, no. 3, pp. 225-228, 2016.