"Physico-chemical models in battery degradation modeling" are mathematical representations of the underlying physical and chemical processes occurring within a battery during operation. These models capture various phenomena, such as lithium-ion transport, electrochemical reactions, and mechanical stress development, which contribute to battery aging. By understanding these processes, researchers can identify the factors that influence "battery degradation" and develop strategies to improve battery performance, safety, and lifespan.
Battery degradation remains a significant challenge in the widespread adoption of lithium-ion batteries in various applications, including electric vehicles (EVs) and renewable energy storage systems. As the demand for longer-lasting, more efficient, and safer batteries increases, understanding and predicting battery degradation has become crucial. Physicochemical modelling is an invaluable tool in this quest, as it enables scientists and engineers to gain insights into the complex aging mechanisms of batteries and develop strategies to mitigate degradation.
Key Components of Physico-chemical Models:
a) Electrochemical Processes: Electrochemical reactions at the electrode-electrolyte interface play a significant role in battery degradation. Physicochemical models often include kinetic models to describe these reactions, taking into account parameters such as current density, temperature, and electrode potential.
b) Lithium-Ion Transport: The transport of lithium ions within the electrode and electrolyte is a critical factor in battery performance. Physicochemical models use relevant laws and equations to describe ion transport in the solid and liquid phases.
c) Thermal Behaviour: Temperature affects battery performance and degradation significantly. Physicochemical models incorporate heat generation and dissipation mechanisms to predict the temperature distribution within a battery, which can help identify potential thermal runaway risks.
d) Mechanical Stress: Mechanical stress development within a battery can lead to electrode cracking and delamination, contributing to degradation. Physicochemical models often include stress-strain relationships and fracture mechanics to understand and predict the effects of mechanical stress on battery aging.
e) Multi-scale Modelling: Lithium-ion batteries comprise various scales, from the atomic to the macroscopic level. Physicochemical models can be developed at different scales, such as the particle level, electrode level, or cell level, to capture the relevant phenomena and interactions contributing to degradation.