Lithium-ion batteries can last many years but sometimes exhibit rapid, nonlinear degradation that severely limits battery lifetime. In this work, we review prior work on "knees" in lithium-ion battery aging trajectories. We first review definitions for knees and three classes of "internal state trajectories" (termed snowball, hidden, and threshold trajectories) that can cause a knee. We then discuss six knee "pathways", including lithium plating, electrode saturation, resistance growth, electrolyte and additive depletion, percolation-limited connectivity, and mechanical deformation -- some of which have internal state trajectories with signals that are electrochemically undetectable. We also identify key design and usage sensitivities for knees. Finally, we discuss challenges and opportunities for knee modeling and prediction. Our findings illustrate the complexity and subtlety of lithium-ion battery degradation and can aid both academic and industrial efforts to improve battery lifetime.
@article{arxiv.2201.02891,
title = {"Knees" in lithium-ion battery aging trajectories},
author = {Peter M. Attia and Alexander Bills and Ferran Brosa Planella and Philipp Dechent and Gonçalo dos Reis and Matthieu Dubarry and Paul Gasper and Richard Gilchrist and Samuel Greenbank and David Howey and Ouyang Liu and Edwin Khoo and Yuliya Preger and Abhishek Soni and Shashank Sripad and Anna G. Stefanopoulou and Valentin Sulzer},
journal= {arXiv preprint arXiv:2201.02891},
year = {2022}
}
Comments
Submitted to the Journal of the Electrochemical Society