The invention relates to a method for determining the
state of health (SoH) of a
battery system (10). The
battery system (10) is, in particular, a stationary
battery storage system. An analysis of the
voltage profile (56) is performed, at least during a
discharge phase (44). The following method steps are carried out: a) Discharging the
battery system (10) until a predetermined target
voltage or a target
state of charge of the battery
system (10) is reached, b) Measurement of the
voltage profiles (56) in the battery
system (10) during the
discharge phase (44), c) Analysis of a voltage profile (56) of the battery system (10) after reaching a
discharge end time SoC_End (50) and d) Determination of the
state of health (SoH) and / or a fault state of the battery system (10) based on measured voltage waveforms (56, 70) during the discharge phase (44) or during relaxation phases (62) following the discharge phase (44) and of reference voltage waveforms (52, 54; 72, 74) recorded before commissioning the battery system (10) for differently aged batteries during discharge or, in the case of de-energized batteries (I = 0
Ampere), for differently aged batteries during relaxation. Furthermore, the invention relates to a device for determining the
state of health (SoH) of a battery system (10), in particular a stationary
battery storage system.