Method and device for adapting a charging current in a battery charger

A device (600) for adapting a charging current in a battery charger, comprising means (603,605,607,609,611) for comparing a detected duty cycle of the charging current pulses with duty cycle limits, and charging current adapting means (613,615) responsive to the comparison adapted to limit or to increase of a predefined quantity the maximum current of the charging current pulses, when the duty cycle of said pulses is above or below the predefined threshold of the duty cycle limits. Said device (600) may be optionally implemented in combination with a phase locked loop (PLL) for monitoring the duty cycle.