Method for charging a battery, as well as a small, battery-operated electrical appliance and a charging circuit

The present invention relates to a method for charging a battery by means of a power supply and also relates to a small, battery-operated electrical appliance and a charging circuit for the small electrical appliance. The method has the following steps: determining the open circuit voltage of the power supply; assigning the determined open circuit voltage of the power supply to a pulse duty factor or modulation factor; and modulating the charging current delivered by the power supply by using this pulse duty factor or modulation factor so that the average power delivered by the power supply does not exceed the maximum allowable output power of the power supply. This assumes that different power supplies differ in terms of their open circuit voltage and maximum output power, wherein power supplies with the same open circuit voltage also have the same maximum output power, so that the power supply's maximum output power can be determined by means of the open circuit voltage. The charging circuit is equipped to carry out this method. A small electrical appliance with such a charging circuit can be charged with different power supplies, namely also with power supplies that would normally overload when charging such small electrical appliance.