Electrical Characterization of Li-Ion Battery Modules for Second-Life Applications

The reuse and repurposing of lithium-ion batteries for transportation in stationary energy systems improve the economic value of batteries. A precise suitability test at the beginning of the second life is therefore necessary. Common methods such as electrochemical impedance spectroscopy (EIS) and current interrupt (CI) analysis, as well as capacity analysis, can be used for testing. In this paper, these methods are studied from the aspects of test duration, sensitivity and acquisition costs of the measuring instruments. For this purpose, tests are carried out on battery modules, which were used for transportation. It is shown that subtle differences are better detected with EIS and less accurately with the CI method. The test duration is fastest with the CI method, followed by EIS and the capacity test. Strongly aged modules are reliably detected with all methods.