Model-based investigation and optimization of electrolyte filling using laser structured electrodes

Abstract

The wetting of battery electrodes with electrolyte is a time- and cost-intensive process step. One of the biggest problems is the time it takes for the liquid electrolyte to be absorbed into the porous electrode. To reduce this wetting time, laser structured electrodes can be used. The resulting grooves facilitate deeper penetration of the electrolyte during the wetting process, leading to faster wetting. Multiphysics simulations and measurement data will be used to optimize the wetting process and to investigate the influence of the structuring geometry on the wetting time. In addition to modelling the structured electrode, achieving a suitable meshing is crucial. Moreover, the physical behavior of the wetting process will be represented by selecting appropriate and realistic boundary conditions. Capillary effects and fluid flow in porous media will be considered to describe the wetting process. The computer model will be validated using measurement data. In this paper it is shown that the wetting time can be significantly reduced by using structured electrodes. It is also shown that the wetting time is further reduced for smaller distances between the grooves. The software COMSOL MULTIPHYSICS will be used to create the model.