A computational study on the effect of stress concentrations on elasticity-electrochemistry interactions in Li-ion battery electrode particle

A Li-ion battery (LIB) anode particle made of graphite is studied to analyze the role of stress concentrations due to voids on the electrochemical behavior. Numerical experiments are carried out on a cylindrical particle of radius (R) with a central hole of radius (r). First, a charge-discharge (CD) voltammetry experiment is simulated; following which the particle is first discharged and then charged (DC). These experiments are conducted for various (r/R) ratios. The results show that for DC case, the effects of stresses on the electrochemical response decreases with the increase in (r/R) ratio, while for the CD case the effects may increase or decrease depending on (r/R) ratio and particle size. Specifically, for particle size less than 5µm the effect of stress reduces with increase in (r/R) ratio and for particle sizes between 5 and 25µm the effect of stress may increase or decrease depending on (r/R) ratio.