In order to operate safely and efficiently, lithium-ion batteries rely on battery management systems to monitor their state and to control their operation. An essential part of this process is modelling battery behaviour under different conditions to predict performance and prevent failures. To do this efficiently, it is crucial to simplify the underlying physical processes, while sacrificing as little accuracy as possible. Through their research, Dr. Luc Raijmakers and colleagues at the Jülich Research Centre, Germany, compare various different approaches to simplifying simulations. Their results could make it easier for battery operators to decide which approach is best suited to their requirements for accuracy and computational efficiency.