Method for loading rechargeable lithium batteries, charger and lithium battery

摘要

The method for charging a rechargeable lithium iron phosphate accumulator (10) for powering an electric power tool, comprises injecting a charging current into the accumulator, monitoring a voltage of the accumulator during the injection process, simultaneously monitoring a variation in time of two state variable characteristics of the accumulator, continuing the injection of the charging current into the accumulator until one of the variations in time of the state variable exceeds respective associated predefined threshold value. The charging current is kept constant over time. The method for charging a rechargeable lithium iron phosphate accumulator (10) for powering an electric power tool, comprises injecting a charging current into the accumulator, monitoring a voltage of the accumulator during the injection process, simultaneously monitoring a variation in time of two state variable characteristics of the accumulator, and continuing the injection of the charging current into the accumulator until one of the variations in time of the state variable exceeds respective associated predefined threshold value. The charging current is kept constant over time, controlled along a predefined time characteristic, and periodically shaped and pulsed. A rise in time of the state variable is monitored. The monitored time variation of the state variable consists of a variation in time of a voltage (dU/dt), a variation in time of a temperature (dT/dt) and a variation in time of an internal resistance (dR/dt) of the accumulator, and a rise in time of the voltage, a rise in time of the temperature and a rise in time of the inner resistance of the accumulator. The charging current is switched off and gradually reduced to zero when the variation in time of the state variable exceeds the predefined threshold value. Independent claims are included for: (1) a charging device for charging a rechargeable lithium accumulator; and (2) a lithium accumulator.