Abstract
The design and operation of performant and safe electric vehicles depend on precise knowledge of the behavior of their electrochemical energy storage systems. The performance of the battery management systems often relies on the discrete-time battery models, which can correctly emulate the battery characteristics. Among the available methods, electric circuit-based equations have shown to be especially useful in describing the electrical characteristics of batteries. To overcome the existing drawbacks, such as discrete-time simulations for parameter estimation and the usage of look-up tables, a set of equations has been developed in this study that solely relies on the open-circuit voltage and the internal resistance of a battery. The parameters can be obtained from typical cell datasheets or can be easily extracted via standard measurements. The proposed equations allow for the direct analytical determination of available discharge capacity and the available energy content depending on the discharge current, as well as the Peukert exponent. The fidelity of the proposed system was validated experimentally using 18650 NMC and LFP lithium-ion cells, and the results are in close agreement with the datasheet.
Funder
the German Federal Ministry of Education and Research FKZ
Subject
Energy (miscellaneous),Energy Engineering and Power Technology,Renewable Energy, Sustainability and the Environment,Electrical and Electronic Engineering,Control and Optimization,Engineering (miscellaneous),Building and Construction
Reference36 articles.
1. (2015, January 29). Paris Declaration on Electro-Mobility and Climate Change & Call to Action. Proceedings of the Lima–Paris Action Agenda, UN Climate Change Conference, Paris, France. Available online: https://unfccc.int/documents/23227.
2. Cao, D., Zhang, H., and Du, H. (2018). Modeling, Dynamics, and Control of Electrified Vehicles, Woodhead Publishing.
3. Lithium-ion cell-to-cell variation during battery electric vehicle operation;Schuster;J. Power Sources,2015
4. Kulkarni, M., Vaidya, A., and Karwa, P. (2015). I2t derivation for Electrical Safety (EV). IEEE Int. Transp. Electr. Conf. (ITEC), 133–135.
5. Hussein, A.-H., and Batarseh, I. (2011, January 24). An Overview of Generic Battery Models. Proceedings of the IEEE PES General Meeting, Detroit, MI, USA. Available online: https://ieeexplore.ieee.org/document/6039674.