Open data model parameterization of a second-life Li-ion battery

Abstract

With the fast expansion of Electric and Hybrid Vehicles, the demand of Li-ion batteries is increasing exponentially. This creates an opportunity for a second life of these cells once they are no longer suitable for their original application. An accurate modelling of the second life can be a powerful tool for these new applications. In this work, we propose a complete second life model parameterization for a Li-Ion cell, with its parameters based on experimental data of NMC/LMO cells cycled through their first and second lives. The resulting model parameters span a State of Health from 80 % to 50 % of the cell original capacity, a State of Charge from 0 to 100 %, two current values and two first life temperature points. The model parameters are presented in an open data fashion in the form of look-up tables, ready to be implemented in simulation softwares.

Extending the electric vehicle battery first life: Performance beyond the current end of life threshold

“…The values of the model parameters ( OCV , , , , and ) are taken from an existing study by Seger et al [49] . Their work provides the look-up tables of a 2RC model for a 2.1Ah Li-ion cell with a NMC + LMO cathode at 25 °C.…”

“…Two cycling conditions during the first life were considered, one at 25 °C (FL25 °C) and another at 0 °C (FL0 °C). For the detailed tables of the parameter values, FL25 °C and FL0 °C, the reader can refer to Appendix A and Appendix B of the aforementioned study, respectively [49] .…”

“…The relationship of the IR with the temperature follows Eq. (3) and is obtained from the literature [51] where the reference IR ( ) is the one at 25 °C obtained from Seger et al [49] . …”

Quantifying the Impact of Battery Degradation in Electric Vehicle Driving through Key Performance Indicators

“…The values of the model parameters (OCV, R i , R 1 , R 2 , C 1 and C 2 ) are taken from an existing study [27]. The work provides the look-up tables of a 2RC model for a 2.1 Ah Lithium-Ion (Li-ion) cell with a NMC + LMO cathode at 25 ºC.…”

Capacity Dispersion and Impact of Outliers in a Second Life Battery

“…A simple electrical model consisting of an open circuit voltage, an internal resistance and two RC branches was used to model the cell and is shown in Figure 3. This model was chosen for its simplicity and ability to be easily implemented [14].…”