End of Life criteria is when the cell is retired from its (first) application, usually a State of health (SoH) of 80% or an increase of the ohmic resistance up to 200% is used for automotive applications. After automotive applications, there might be a second life in stationary applications with different EoL criteria (e.g. 50% SoH) possible.
A remaining capacity of 80% might seem as like an arbitrary choice for retiring the cell from its primary application but it might have its origins in rapid cell degradation going beyond this State of health of the cell. Above 80% of the remaining capacity, the capacity fading and resistance increase is generally observed in a quasi-linear way. After the 80% to 70% crossing, capacity fading and resistance increased behave in a more non-linear way, which makes longer term forecasts more challenging. While the above characteristic parameters have been defined for cells, they are also widely used for higher levels such as for modules, systems and batteries.