A Critical Look at Coulomb Counting Approach for State of Charge Estimation in Batteries

Kiarash Movassagh, Arif Raihan, Balakumar Balasingam and Krishna Pattipati
Additional contact information
Kiarash Movassagh: Department of Electrical and Computer Engineering, University of Windsor, Windsor, ON N9B 3P4, Canada
Arif Raihan: Department of Electrical and Computer Engineering, University of Windsor, Windsor, ON N9B 3P4, Canada
Balakumar Balasingam: Department of Electrical and Computer Engineering, University of Windsor, Windsor, ON N9B 3P4, Canada
Krishna Pattipati: Department of Electrical and Computer Engineering, University of Connecticut, Storrs, CT 06269, USA

Energies, 2021, vol. 14, issue 14, 1-33

Abstract: In this paper, we consider the problem of state-of-charge estimation for rechargeable batteries. Coulomb counting is a well-known method for estimating the state of charge, and it is regarded as accurate as long as the battery capacity and the beginning state of charge are known. The Coulomb counting approach, on the other hand, is prone to inaccuracies from a variety of sources, and the magnitude of these errors has not been explored in the literature. We formally construct and quantify the state-of-charge estimate error during Coulomb counting due to four types of error sources: (1) current measurement error; (2) current integration approximation error; (3) battery capacity uncertainty; and (4) timing oscillator error/drift. It is demonstrated that the state-of-charge error produced can be either time-cumulative or state-of-charge-proportional . Time-cumulative errors accumulate over time and have the potential to render the state-of-charge estimation utterly invalid in the long term.The proportional errors of the state of charge rise with the accumulated state of charge and reach their worst value within one charge/discharge cycle. The study presents methods for reducing time-cumulative and state-of-charge-proportional mistakes through simulation analysis.

Keywords: battery management system; state of charge; Coulomb counting; battery capacity; measurement errors; battery impedance; equivalent circuit model (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2021
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (12)

Downloads: (external link)
https://www.mdpi.com/1996-1073/14/14/4074/pdf (application/pdf)
https://www.mdpi.com/1996-1073/14/14/4074/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:14:y:2021:i:14:p:4074-:d:589345

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().