Modeling electrode-level crack and quantifying its effect on battery performance and impedance

摘要: Abstract Electrode-level cracks in a Li ion battery significantly impact its performance. We build crack-containing electrochemical model to reveal the mechanism and quantify effect of crack geometrical characteristics on specific energy, capacity cell impedance. An elliptical-shaped is introduced into electrode, which represents various configurations by changing semi-axis ratio, angle position. show that lithium transport, intercalation overall impedance are sensitive electrotype absorption surfaces. A longer more parallel current collector reduces energy significantly, especially when density high. By contrast, perpendicular has little impact. The dependence series orientation quantified. study position shows closer separator stronger negative impact, dramatically reducing capacity. Electrochemical spectroscopy simulations shape factors such as electrolyte wetting ratio primarily affect ohmic resistance. increases resistance, while affects charge transfer resistance but with connected an open or closed ring also considered, can partially isolate active materials from electrode depending size opening. This work provides comprehensive fundamental understanding how parameters behavior, assist evaluating significance cracking, allow comparison other degradation mechanisms identify limiting factor, provide guidance design application strategy.