Low Frequency influence on degradation of commercial Li-ion battery

The Tesla model 3 has rapidly become one of the most popular electric vehicles (EV), being the best selling EV in 2020 and the second best selling in 2021. In this paper the ageing implications of varying time scales in usage of the battery are investigated for the 2170 cells used in the Tesla model 3. It is shown that dynamic usage in the range of approximately 0.01 to 0.1 Hz has a statistically significant impact on ageing, while dynamic usage in range 0.1 to 1 Hz does not show significant impact on ageing. Furthermore the individual electrode ageing is investigated by non-invasive electrochemical techniques, revealing the profound impact on ageing from Si addition to the negative electrode, where it is shown that substantial part of the ageing comes from loss of Si in the negative electrode.