Examining Contrasting Excitation Modes within Battery Characterisation using Maximum Length Sequences

Inhalt:
This paper extends on previous work involving the use of maximum length sequences as tools for parameter estimation within electrochemical batteries[1-4] and comprises a study of the modes of application of a perturbation signal to batteries in the form of discharge, charge and bipolar charge/discharge arrangements driven by a frequency rich signal. Examinations are made of the contemporary techniques, and by the use of experiments over a range of States-of-Charge, the advantages of each method are presented. Using a series of experiments, impedance responses are produced using the tests batteries under perturbation from each of the test modes. Analysis of these results under comparative test conditions allows observations to be made regarding the application of each mode, and proposals are made for the complementary inclusion of the test regimes in a hybrid SoC/SoH prediction system.