Lithium-ion battery model and experimental validation

The development of an accurate battery model is essential for the design of any energy storage system and the power converter connected to it. This paper reports on an experimental characterization, modelling and validation of a commercial NMC lithium-ion battery with a rated voltage of 133 V and a rated capacity of 40 Ah. It is a straightforward model, which can be used to predict the behaviour of the battery in realistic situations. For the purpose of parameters fitting, tests with the whole commercial battery pack have been performed, giving as a result a suitable model to predict the final performance of the system. This model is a useful tool to optimize the size of the battery needed in a specific application and to design other elements of the system as power converters or control strategies. Moreover, the methodology proposed in this paper can be used to develop models of other types of lithium-ion batteries. The characterization experiments are easily replicable and the proposed electric circuit is valid for other lithium-ion batteries.