Abstract: A charging device for charging an electric energy storage device includes a power supply circuit connected to a power supply, an alternating current conversion circuit configured to convert a current from the power supply connected to the power supply circuit to a first alternating current with a preset frequency value, a transformer configured to convert the first alternating current to a second alternating current, wherein a voltage value corresponding to the second alternating current being less than a voltage value corresponding to the first alternating current, and a direct current voltage conversion circuit configured to convert the second alternating current to a direct current with a waveform fluctuating in a preset range, so as to charge an electric energy storage device.

Abstract: A charging device for charging an electric energy storage device includes a power supply circuit connected to a power supply, an alternating current conversion circuit configured to convert a current from the power supply connected to the power supply circuit to a first alternating current with a preset frequency value, a transformer configured to convert the first alternating current to a second alternating current, wherein a voltage value corresponding to the second alternating current being less than a voltage value corresponding to the first alternating current, and a direct current voltage conversion circuit configured to convert the second alternating current to a direct current with a waveform fluctuating in a preset range, so as to charge an electric energy storage device.

Abstract: A power supply device includes a battery pack for storing electric energy and an adapter for outputting the electric energy stored in the battery pack. The battery pack includes a battery controller for detecting the voltage of the battery pack. The adapter includes an adapter controller for receiving a signal sent by the battery controller and stopping the adapter outputting the electric energy when a length of time that the battery pack has the voltage less than a predetermined voltage threshold reaches a predetermined length of time.

Abstract: A battery pack, a method for detecting the battery pack, a charging assembly, and an electric tool are provided for detecting voltage and disconnection of the battery cells. The battery pack may have an output voltage of at least 56V and may include a plurality of series connection units. A voltage detecting module may be utilized for detecting voltage in the battery pack. A battery control module configured to control voltage detecting module may also be employed. The method may involve determining whether the series connection units are disconnected based on rates of voltage change or internal-resistance of the series connection units.

Abstract: A battery pack, a method for detecting the battery pack, a charging assembly, and an electric tool are provided for detecting voltage and disconnection of the battery cells. The battery pack may have an output voltage of at least 56V and may include a plurality of series connection units. A voltage detecting module may be utilized for detecting voltage in the battery pack. A battery control module configured to control voltage detecting module may also be employed. The method may involve determining whether the series connection units are disconnected based on rates of voltage change or internal-resistance of the series connection units.