Analysis of the limitation factors of thick cathodes based on experimental and P2D model simulations

Abstract

The thickness of the electrode significantly impacts battery performance. Increasing electrode thickness contributes to higher energy density, but it also leads to a decline in rate capability and stability. Therefore, a balance must be struck when determining electrode thickness. In this context, we compare experimental results with numerical simulations to reveal the primary reasons behind the drastic reduction in battery capacity and rate performance due to excessively thick electrodes. At the same time, there is minimal difference between experimental and simulated results at lower electrode thicknesses and smaller currents. As the electrode thickness and current increase, experimental performance deteriorates more rapidly, which arises from the uneven distribution of various components within the cathode during the drying process. In addition, we also simulated the capacity of the crack-free electrode and the depth of discharge at various locations within it, thus determining the main factors of its capacity decline.