Solid oxide fuel cells (SOFCs) are considered as a future of clean energy systems. Due to the limited voltage of a single unit, SOFCs are commonly connected in series or parallel to form the so-called fuel cell stack. Mathematical descriptions of the physics involved combined with numerical simulations are proven to be fast and reliable tools that help in the design and evaluation of both single SOFCs and whole stacks. The paper presents an investigation on how the electrochemistry and level of detail of microstructure’s features introduced in the model impact stack-level prediction. The study compiles the results of microscale simulations, macroscale simulations, as well as multiscale simulations balancing micro- and macroscale phenomena occurring in an SOFC device. As a starting point, a fully three-dimensional microscale model is discussed. The microscale model allows to investigate the current generation and gas diffusion characteristics in detail. However, being computationally expensive, the microscale model focuses on the porous microstructure of electrodes. A multiscale model was proposed to examine relations between microstructure characteristics and single-cell or stack performance. The multiscale model focuses on mass and heat transfer in the whole system. Nonetheless, the microstructure of electrodes is still considered, although the microstructural input is simplified. The high computational cost of the multiscale model makes it unusable for the analysis of stacks of several cells or SOFC-based systems. Therefore, a macroscale model was developed. The macroscale model further simplifies the description of gas diffusion and electrochemical characteristics, but the relations between large scale current generation characteristics, the flow of gases, and the thermal behavior are revealed.