Technical Papers and Presentations

Batteries are considered a key technology for the transition to climate neutrality. There is an urgent need to improve the resource efficiency of existing technologies while transitioning to next-generation battery systems. A mechanistic battery model is a powerful tool to accelerate this development by guiding the design and optimization of battery systems as a compliment to experimentation. We showcase an extensive simulation study involving parameter fitting, validation, and sensitivity study of the lifetime of a conventional Graphite/NMC single battery cell (base-case). The bottleneck of the base-case battery was identified and optimised, resulting in a battery power performance increase in the desired operating conditions by optimising battery design. Furthermore, we quantify the battery cell resistivity resulting from the inter-cell joining method for input to battery pack simulations. The simulation model constitutes a mechanistic battery chemistry model incorporating degradation mechanism (solid-electrolyte interface layer formation) [1] using COMSOL’s custom PDE interfaces, all incorporated in the classical Doyle-Fuller-Newman pseudo-2D formulation [2]. We present a framework for model parameter identification using large amount of experimental battery data related to degradation cycling. The “COMSOL Application Builder” is used to preprocess the data and initialise and run the simulations at the given conditions. A rigorous simulation-based approach of battery cycling is adopted to ensure that model parameters are applicable at all relevant conditions. Hence, the models are suitable inputs for COMSOL’s Surrogate Model to represent a battery cell with high fidelity and low computational cost. The aim of the surrogate model is to perform full battery pack simulations, incorporating the elements of chemistry (battery operation) and manufacturing (battery pack connection resistivity).