A Simulation Method to Determine the RF Impedance of Batteries

Today's application of batteries in transportation systems and portable devices as part of the electric board makes it susceptible to electromagnetic interferences. Implemented inverters and DC-DC-converters in such systems generate disturbances at switching frequencies and their harmonics, which can be led into the battery system. For this reason it is important to determine the input impedance of the used battery. So far most presented methods to determine RF impedances of batteries are based on experimental measurements. Although some analytical methods are presented to calculate impedances of batteries, however such methods are reasonable only for simple cells and arrays structures. This work presents a simulation method to determine the RF impedance of batteries. The method can be used to determine the impedance of any arbitrary cells and complex array structures. The method is applied on cylindrical and prismatic cells and it shows a good agreement with measured results.