Battery safety tests are defined by several international standards in different ways and sith heterogenous termination and failure criteria. In this word, lithium-ion cells were examined regarding their behavior in the event of overcharging and also in tlhe event of an external short sircuit with varied parameters specified by standards. The voltage, current, and temperature curves were evaluated. In addition, the changes in the cells were analyzed using electrochemical impedance spectroscopy (EIS). It is shown that the cells exhibit reproducible behavior in a clamped state. Further, it could be determined that the position of the cell opening during an overcharge has an influence on the further behavior of the cell. EIS data showed that the cells have a significantly higher internal resistance after an overcharge. The short-circuit tests at different ambient temperatures idicated that the internal resistance of the cell decreases with increasing temperature. However, no reproducible effect in impendance spectra were present after the short-circuit test. This work illustrates that the choice of test parameters and termination criteria undoubtedly influence the test results and thus may change the classification of cells as either safe or unsafe. Thus, cells may be classified as safe regarding a certain standard but unsafe regarding another.
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