Battery packs are used in wide scope of applications (e.g. stationary, mobile devices, etc.) at varying conditions (e.g. power load, cyclic load, etc.). Because a battery pack consists of several battery cells, the battery pack life depends on single cell characteristics and properties. Post-mortem analysis is used to investigate individual aging mechanisms and assess influencing factors (e.g. manufacturing defects, production tolerances, material dependent parameters, etc.). Here, single cells are opened during or after aging and inspected for changes to the structure or material composition to draw conclusions about processes which are occurring as well as potential optimization measures or further development of new battery concepts. In addition, the geometrical and material data obtained can be processed to create or refine physical-chemical models.
Depending on the battery technology (e.g. coin cells, round cells or pouch cells) under investigation, the opening of the cell and further analysis must be performed under certain conditions. For example, the cell must be disassembled in a protective environment (e.g. using a glovebox), shielding the battery components from the influence of air, water and nitrogen. A broad range of analysis techniques (e.g. laser-scanning-microscope, wet-chemical) is available. These require not only expertise regarding the features of the technical device, but also the electro-chemical processes concerning the battery cells.