Authors: Fangzheng Liu | Shu Zhao | Haijun Yu
Source: Chinese Science Bulletin (Chinese Version) (article, 2024-07-25)
Field: Materials Science — Materials Chemistry

Applications and prospects of phase field simulations of local structures in lithium-ion battery materials <p indent="0mm">In light of the depletion of fossil fuels and the environmental deterioration caused by excessive fossil fuel consumption, the large-scale utilization of renewable energy and the clean, low-carbon transformation of conventional energy sources have become essential trends for addressing energy security and environmental pollution. Energy storage technology, particularly lithium-ion batteries (LIBs), has emerged as a critical component of renewable energy systems due to its numerous advantages such as high volume and mass energy density, long cycle life, high output voltage, no memory effect, and minimal environmental impact. Over recent decades, LIBs have rapid development and applications, significantly advancing the consumer electronics, electric vehicle, and large-scale energy storage power stations. Despite substantial research and significant improvements in energy density, power performance, and cycle life, the performance of LIBs still falls short of meeting the increasing range demands of electric vehicles and the requirements of energy storage grids. Thus, further enhancements in LIB energy density are necessary. Fundamental improvements in battery performance hinge on the design and optimization of materials, a process that requires a deep understanding of the multi-dimensional and multi-scale characteristics of LIB material structures. The enhancement of lithium-ion battery performance depends on an in-depth understanding of the multi-dimensional and multi-scale characteristics of the material structures. Besides the average structure, the functionality of local structures and the synergistic effects among different local structures profoundly impact battery performances. However, challenges persist in accurately characterizing and simulating these aspects. Phase field simulation, as a multi-scale and versatile method, offers significant potential and advantages in revealing the design and dynamic evolution of local structures. At present, electrochemical phase field simulations mainly focus on the local-structural failure analysis of batteries. As market demand for high-performance lithium-ion batteries continues to increase, researchers are delving deeper into the multi-scale structures within lithium-ion batteries. From the perspective of local structures of lithium-ion battery materials, there remains considerable room for development in phase field simulations. Therefore, maximizing the advantages of phase field simulations in exploring local structures, integrating extensive studies on the design and dynamic evolution of LIBs local structures, providing robust theoretical support, and constructing structure-function relationships between the micro-region structure and properties of LIBs from a mesoscopic scale are critical tasks. Ultimately, achieving the guiding role of material optimization design will be a significant and challenging endeavor. This paper first reviews the significance of local structures for lithium-ion battery materials, followed by a discussion on the basic theoretical foundation of phase field simulations and electrochemical phase field models, with a brief introduction to the construction of evolution equations and system free energy density. Furthermore, from the perspective of local-structural failure analysis in lithium-ion battery materials, this paper systematically summarizes the research progress in phase field simulations concerning lithium electrochemical deposition and dendrite growth, phase separation and ion diffusion, crack propagation, etc. Finally, by integrating the advancements in electrochemical phase field simulations with lithium-ion batteries, the paper elucidates the importance of combining phase field simulations with first-principles calculations and other methods to form multiscale simulation tools, and highlights the potential applications of phase field methods in the design and evolution of local structures in lithium-ion battery materials. Computer science Solidification and crystal growth phenomena ; Metallurgical and Alloy Processes ; Chemical and Physical Properties of Materials