Influence of state of charge window on the degradation of Tesla lithium-ion battery cells
Journal article, 2024

The Tesla Model 3 is currently one of the most popular electric vehicle (EV) and was the best selling EV in 2020. In this article, performance and degradation of 21700 cylindrical cells, taken from a new vehicle, were studied by cycling within 10% State of charge (SOC) windows. Cells tested in either very high and very low SOC windows show faster degradation than at moderate SOC. In particular, the shortest service life was for cells cycled below 25% SOC. The ageing mechanisms of the cells cycled in these most extreme windows have been monitored by non-destructive electrochemical methods including analyses of differential voltage, incremental capacity, and voltage hysteresis. The combination of loss of lithium inventory (LLI) accelerated in early cycling by SiOx utilization, paired with loss of active material (LAM) of SiOx are responsible for the most rapid ageing, which is observed in the cells cycled in the 5%–15% SOC window. Calendar ageing, however, is not accelerated by storage at low SOC. The results from this study offer an understanding of the distinct, SOC-dependent ageing patterns observed in the cells. This understanding of the ageing mechanisms in different cycling and storage conditions can be used to recommend improved customer usage patterns and substantially extend the lifetime of lithium-ion batteries in operation.

Electric vehicles

Silicon oxide

Battery aging

State of charge influence

Voltage hysteresis

Li-ion battery

Author

Niladri Roy Chowdhury

Volvo Group

Chalmers, Electrical Engineering, Electric Power Engineering

Alexander J. Smith

Royal Institute of Technology (KTH)

Kristian Bartholdsson Frenander

Chalmers, Electrical Engineering, Electric Power Engineering

Volvo

Anastasiia Mikheenkova

Uppsala University

R. W. Lindstrom

Royal Institute of Technology (KTH)

Torbjörn Thiringer

Chalmers, Electrical Engineering, Electric Power Engineering

Journal of Energy Storage

2352-152X (eISSN)

Vol. 76 110001

Subject Categories

Subatomic Physics

Other Chemical Engineering

Probability Theory and Statistics

DOI

10.1016/j.est.2023.110001

More information

Latest update

1/11/2024