Hazard classification of different lithium-ion battery types after triggering thermal runaway

Abstract

For a better understanding of relevant parameters influencing the thermal runaway, this work classifies the behavior of six different types of lithium-ion batteries. Based on 145 repeatable tests, this research has created a unique and detailed database of battery behavior during thermal runaway. It contains information about changes in cell temperature, voltage, mass loss, smoke gas release and gas pressure. When it comes to characterizing the thermal runaway behavior across different cell types, this work eliminates the need for complex meta-analyses, which can only provide limited information due to the different test conditions in different test benches. In a pressure-resistant 100-dm³ autoclave and an 8-m³ room with connected multi gas analysis, 24 setups were examined under identical conditions. The investigations were carried out as a function of the variation parameters cell geometry, cathode active material, state of charge and initiation method of thermal runaway. The analysis of the measurement data reveals clear differences in the thermal runaway behavior of the tested cell types and can be used as a reference for determining the hazard potential in individual assessment categories of different cells.

All measured values from both test benches as well as the visual evaluation of the cell behavior during the test runs in the 8-m³ room are made available in a comprehensive data table in the supplementary material.