Abstract: A method for detecting whether a battery (110) is disconnected from a battery charger (120). The method comprises determining (S1) if the battery charger (120) is charging the battery (110), and obtaining (S2) a charger model indicative of a first expected output voltage (Umod) of the battery charger (120) as a function of time when the battery charger (120) is connected to, but not charging, the battery (110). When it is determined that the battery charger (120) is not charging the battery (110), the method comprises: measuring (S3) a first measured output voltage (Umeas1) of the battery charger (120) as a function of time; and determining (S4) if the battery (110) is disconnected from the battery charger (120) based on whether the first measured output voltage (Umeas1) differs from the first expected output voltage (Umod) by more than a first threshold value at one or more corresponding points of time.