Detection of inhomogeneities in serially connected lithium-ion batteries

Title data

Rüther, Tom ; Plank, Christian ; Schamel, Maximilian ; Danzer, Michael A.:
Detection of inhomogeneities in serially connected lithium-ion batteries.
In: Applied Energy. Vol. 332 (2023) . - 120514.
ISSN 1872-9118
DOI: https://doi.org/10.1016/j.apenergy.2022.120514

Official URL:

Abstract in another language

Serially connected batteries present a cell-to-cell variation in their electrochemical behavior that tends to increase over the lifetime. The decision for the best circular economy option for aged or defective battery packs – i.e., repair, remanufacturing, or recycling – requires comprehensive testing, analysis, and an according data basis. Remanufacturing of battery packs refers to the replacement of individual (sub-)modules or cells which are defective or show a diverging aging behavior to the rest of the battery units. A detection algorithm is required to decide if a significant inhomogeneity in a serial connection of batteries is present. For this reason, virtual battery packs are built based on the measurement of 12 individual batteries of the same type. Cell-to-cell variations are determined at the begin of life and a novel representation for the quantitative and qualitative analysis is given. This work extracts impedance-based features of different serial battery pack configurations through a novel comparative analysis approach. The features are extracted from Bode and Nyquist plots and the real and imaginary parts of the impedance itself. The detectability is analyzed depending on the number of cells and the underlying effects are discussed. A detailed sensitivity analysis is carried out for the most promising features, in which the influence of the cell-to-cell variations, the aging condition, and the aging mechanism are analyzed. The feature that shows the highest sensitivity, the so called low-frequency minimum, is able to detect single outliers within a high number of serially connected cells.

Further data

Item Type:	Article in a journal
Refereed:	Yes
Keywords:	Detection of inhomogeneities; Battery pack; EIS; Cell-to-cell variation; Circular economy decision; Battery module
Institutions of the University:	Faculties Faculties > Faculty of Engineering Science Faculties > Faculty of Engineering Science > Chair Electrical Energy Systems Faculties > Faculty of Engineering Science > Chair Electrical Energy Systems > Chair Electrical Energy Systems - Univ.-Prof. Dr. Michael Danzer Research Institutions > Central research institutes > Bayerisches Zentrum für Batterietechnik - BayBatt Research Institutions Research Institutions > Central research institutes
Result of work at the UBT:	Yes
DDC Subjects:	600 Technology, medicine, applied sciences > 620 Engineering
Date Deposited:	22 Dec 2022 06:22
Last Modified:	25 Aug 2023 09:15
URI:	https://eref.uni-bayreuth.de/id/eprint/73182