Battery charger with charging current variation based on a temperature difference between the battery and its environment

摘要

A battery charger whose charging current is shut off on the basis of the temperature difference between the ambient temperature, measured by means of a first sensor (RA), and the battery temperature, measured by means of a second sensor (RB). The error in the measurement of the temperature difference, which is caused by the input voltage dependent heat generation by the power supply (PS) in the battery charger, is compensated by a third signal (k*Vi) which is representative of the anticipated additional heat generation as a result of a varying input voltage (Vi).