Phase-Field Simulation of Lithium Dendrite Growth in Multidirectional Constrained Spaces within Solid Electrolyte Interphase

Lithium-ion batteries (LIBS) are the mainstream of current battery technology and are widely used in power, consumer, and energy storage batteries. However, during the charging and discharging process of LIBS, lithium dendrites are formed on the surface of the anode due to uneven lithium deposition. The growth of lithium dendrites can cause a number of safety issues, which limit the further application of LIBS. This study employs a simulation-based analysis to systematically investigate the growth characteristics of lithium dendrites in the multidirectional constrained space of the solid electrolyte interphase during charging. A 2D phase field model for simulating lithium dendrite growth is proposed. The growth direction of lithium dendrites in the solid electrolyte interface of actual batteries in confined spaces and the direction of the electric field at various specific angles are considered. This is achieved by adjusting the angle and width of the confined space geometric model. The results show that minimizing the magnitude of the width and the angle of the confined space results in the maximize dendrite propagation time, which suppressing the rate of dendrite formation. Additionally, a critical threshold at about 30° emerges, where growth duration is possible to be minimized when the value of width is relatively small, suggesting a possible optimal angle for dendrite suppression strategies. This study offers further guidance for revealing the growth mechanism of lithium dendrites.