Spatially resolved model for lithium-ion batteries for identifying and analyzing influences of inhomogeneous stress inside the cells

Abstract

Performance, safety and lifetime of Li-ion batteries are closely connected topics, which are significantly influenced by electrical and thermal inhomogeneities occurring during operation inside the system. For R&D of battery packs it is a key issue to identify these inhomogeneities and to minimize the stress inside the cells by means of adequate cell designs and cooling strategies. For prismatic Li-ion cells a new model approach is developed: a spatially resolved thermo-electrical battery model combined with an event-oriented physico-chemical stress model. Considering several battery pack configurations the model enables simulation of electrical and thermal behavior and analysis of stress phenomena inside the cell throughout a complete life cycle.