Abstract
Several studies show that impedance spectroscopy is a suitable method for online battery diagnosis and State-of-Health (SoH) estimation. However, the most common method is to model the acquired impedance spectrum with equivalent circuits and focus on the most sensitive parameters, namely the charge-transfer resistance. This paper introduces first a detailed model of a battery cell, which is then simplified and adapted to the observable spectrum behavior. Based on the physical meaning of the model parameters, we propose a novel approach for SoH assessment combining parameters of the impedance spectrum by building the ratio of the solid electrolyte interphase (SEI) resistance to the total resistance of SEI and the charge transfer. This ratio characterizes the charge-transfer efficiency at the electrodes’ surfaces and should decrease systematically with SoH. Four different cells of the same type were cycled 400 times for the method validation, and impedance spectroscopy was performed at every 50th cycle. The results show a systematic correlation between the proposed ratio and the number of cycles on individual cell parameters, which build the basis of a novel online method of SoH assessment.
Highlights
State-of-Health (SoH) defines the usability of the battery for an application and plays a crucial role in the accurate estimation of the remaining state-of-charge (SoC) of a battery
We propose a SoH assessment method based on impedance spectroscopy for the online diagnosis of battery cells, which could be applied without needing precycling information or being tuned by considering individual cell parameters
This review shows that most literature directly uses the impedance spectrum, or a direct value of the equivalent circuit model (ECM), which is correlated with the capacity or number of cycles
Summary
State-of-Health (SoH) defines the usability of the battery for an application and plays a crucial role in the accurate estimation of the remaining state-of-charge (SoC) of a battery. Most studies in the literature associate the SoH of the battery with either a capacity fade, inferring mainly a decrease in the charge storage ability, or a power fade, inferring primarily the increase of impedance limiting the extractable power, or associated with both [1,2,3,4]. These methods are grouped into experimental and adaptative methods. Electrons are transported one electrode the during other during. Electrons are transported from from one electrode to theto other chargecharge or dis‐. The battery cell,current this current is charge processes through the external circuit.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
