How does a lithium-ion battery degrade over time and what shortens its life?

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1. 1

   Review of State-of-the-Art Degradation Models for Lithium-Ion Batteries.

   Entropy (Basel, Switzerland) (Tiwari et al.)Published Jun 11, 2026Checked Oct 17, 2026

   “Lithium-ion batteries (LIBs) are widely used across a range of applications; however, they degrade over time due to various factors, including repeated charge-discharge cycling, material aging, and environmental conditions. Degradation models play a crucial role in predicting the lifespan of LIBs and in optimizing their design and operational strategies. This paper presents a comprehensive review of state-of-the-art degradation models for LIBs. The reviewed models primarily address key degradation mechanisms, including solid electrolyte interphase (SEI) formation, lithium plating, and particle fracture. For each mechanism, the underlying modeling approaches, their development, advantages, limitations, and associated challenges are critically discussed. Finally, this review identifies existing gaps in battery degradation modeling and proposes the Unified Mechanics Theory (UMT), which is the unification of laws of Newton and the second law of thermodynamics, and uses entropy as a degradation metric, as a promising alternative framework for capturing the coupled and multifaceted nature of battery degradation processes.”

2. 2

   Review on degradation mechanism and health state estimation methods of lithium-ion batteries

   Journal of Traffic and Transportation Engineering (English Edition) (Liu et al.)Published Jul 27, 2023Checked Oct 17, 2026

   “Based on the research trends, findings regarding the internal and external degradation mechanisms and influencing factors of (LIBs) are reorganized, and chemical and physical degradation processes, including solid electrolyte interface (SEI) layer formation, fracture, Li plating, and dendrite formation, are systematically introduced based on the modeling perspective. The interrelationships between these degradation factors and their effects on capacity and power decay as well as their correlation with SOH estimation are evaluated. Additionally, a comparative analysis of existing SOH estimation methods is presented, and the applicable scenarios and technical problems of each method are summarized. The key issues such as model simplification, estimation methods based on random data, and second-life SOH are also analyzed and discussed. The results show that the estimation results of methods mixing multiple models tend to be more accurate. Finally, the development trend of SOH estimation methods under complex degradation conditions and usage scenarios is analytically discussed.”

3. 3

   Physics-Based and Data-Driven Modeling of Degradation Mechanisms for Lithium-Ion Batteries—A Review

   IEEE Access (Ruiz et al.)Published Jan 1, 2025Checked Oct 17, 2026

   “Linear degradation models can be inaccurate in capturing the highly nonlinear behavior of LIB degradation caused by multiple simultaneous degradation mechanisms. Hence, this work first analyzes the main different mechanisms, their causes, and their interrelations. Secondly, the various single- and multi-mechanism physics-based (PB) and data-driven (DD) models for LIB degradation and knee-point identification are summarized and compared regarding their prediction performance on degradation and transition from stabilized to saturated aging. While single-mechanism PB models can be effective in the LIB first-life prediction, they can seriously undermine the knee-point and saturated aging. Moreover, the modeling of the different aging mechanisms can significantly increase the complexity of the multi-mechanism PB models. Finally, while DD models for LIB degradation have been developed, a DD model focused on knee-point identification and LIB second-life is still missing from the literature.”

4. 4

   Lithium-Ion Battery Degradation: A Comprehensive Review of Mechanisms, Influencing Factors, Diagnostic Methods, and Lifetime Prediction

   Preprints.org (Deepanshu et al.)Published Sep 9, 2026Checked Oct 17, 2026

   “The review examines solid-electrolyte-interphase growth, lithium plating, particle fracture, cathode reconstruction, transition-metal dissolution, electrolyte decomposition, separator damage, and electrode cross-talk. These processes contribute to lithium loss, active-material loss, electrolyte depletion, stoichiometric imbalance, impedance growth, capacity fade, and power fade. The effects of temperature, state of charge, depth of discharge, current rate, ageing history, chemistry, and cell design are assessed, with emphasis on coupled mechanisms, spatial non-uniformity, path dependence, and knee-point ageing. The review also discusses state-of-health estimation, remaining-useful-life prediction, mitigation strategies, and digital-twin approaches. Capacity alone is insufficient because similarly aged cells may differ in resistance, safety margin, and future lifetime. Future research should prioritize realistic pack-level datasets, uncertainty-aware prediction, standardized testing, operando diagnostics, transferable models, and decision-oriented battery management.”

5. 5

   A review of float charging in lithium-ion batteries: Degradation mechanisms, influencing factors, and optimization strategies

   Journal of Power Sources (Khan et al.)Published Mar 7, 2026Checked Oct 17, 2026

   “As a result, float charging, which involves supplying a low, continuous current to maintain the battery's charged potential and counteract self-discharge, is used to ensure batteries remain fully charged. However, prolonged float charging can lead to battery degradation caused by electrolyte decomposition, deposition of metallic lithium, and structural changes of the electrodes, compromising battery lifespan, performance, and safety. This review discusses the factors that influence float charging behavior, including the selection of float voltage, and ambient temperature. It also examines the associated degradation mechanisms and strategies to optimize float charging conditions for improved performance and longevity in stationary energy storage applications. • Reviews float-charge degradation mechanisms in lithium-ion batteries. • Analyzes the effects of float voltage and temperature on battery life. • Summarizes strategies to mitigate float-induced degradation and extend battery life.”

6. 6

   Capacity Degradation Assessment of Lithium-Ion Battery Considering Coupling Effects of Calendar and Cycling Aging

   IEEE Transactions on Automation Science and Engineering (Liu et al.)Published May 17, 2023Checked Oct 17, 2026

   “Unlike previous research that only supplied experimental results to qualitatively illustrate the existence of the coupling effect between these two aging sources, this study provides procedures to quantitatively test the significance of such an effect. In addition, previous research ignored the coupling effect in the degradation modeling as it is difficult to capture, this study propose the concept of CUCD to characterize it. The CUCD is also introduced as a stress factor for cycling aging, which is based on the fact that a battery will degrade faster when it experiences charge/discharge cycle continuously for a longer time. Hypothesis testing is also provided to illustrate this monotonicity. To deal with another challenge that the expert knowledge of the functional form between cycling aging and CUCD is unavailable except for the monotonicity, a nonparametric method with the shape-restricted spline is adapted. The estimation procedures for the model parameters are also presented.”