The disclosure provides an electric energy storage device which includes four energy units with a substantially same voltage value. Each energy unit is provided with a positive electrode and a negative electrode. The electric energy storage device comprises a socket with eight independently arranged electrode terminals that are connected with the four energy units. The disclosure also provides an electric tool system using the electric energy storage device. The electric tool is provided with plugs that may be connected with the four energy units in different states, allowing the electric energy storage device to output multiple voltages.

An energy storage system (ESS) battery pack includes a battery module having a plurality of battery cells and a cell housing provided in a hollow board shape to accommodate the plurality of battery cells therein; and a system module disposed on a lower portion of the battery module and including a battery management system, and a box-shaped system housing including a docking unit formed to accommodate the battery management system in one side of an inside and vertically insert a lower end of the cell housing into the other side. When the cell housing is lifted from the docking unit, the battery module is provided to be separated from the system module.

An electronic device according to various exemplary embodiments of the present invention may include one or more switches, one of more sub-systems, and an interface control unit electrically coupled with the one or more sub-systems and the one or more switches. The interface control unit is configured to: detect a coupling of an external device to the electronic device, identify a type of the coupled external device, when the external device is identified as a current detecting device, generate a first control signal for turning off power to the one or more sub-systems, and a second control signal for setting a first path to supply the one or more sub-systems with power from the current detecting device, and transmit the first control signal to the one or more sub-systems and the second control signal to the one or more switches.

The invention relates to a power tool and battery pack assembly including a battery pack for connection with the power tool to provide power for the operation of the power tool when connected thereto. The battery pack includes a plurality of power cells and connection means are provided to allow the selective supply of power at least a first or second voltage level to the power tool from the battery pack.

The invention relates to a power tool and battery pack assembly including a battery pack for connection with the power tool to provide power for the operation of the power tool when connected thereto. The battery pack includes a plurality of power cells and connection means are provided to allow the selective supply of power at least a first or second voltage level to the power tool from the battery pack.

A power station assembly includes two inverter power stations configured to provide respective power outputs at a voltage and at respective currents. The power station assembly additionally includes a linking module configured to electrically connect to the two inverter power stations to receive the respective power outputs therefrom, combine the respective power outputs into a combined power output, and provide the combined power output to a load.

A power station assembly includes two inverter power stations configured to provide respective power outputs at a voltage and at respective currents. The power station assembly additionally includes a linking module configured to electrically connect to the two inverter power stations to receive the respective power outputs therefrom, combine the respective power outputs into a combined power output, and provide the combined power output to a load.

The present disclosure is directed to a convertible battery pack having an improved switching circuit. The switching circuit includes a converter element having a plurality of contacts positioned in the converter element such that as the converter element slides within the battery pack the contacts move from a first position to engage a first set of contact pads to a second position to engage a second set of contact pads. The converter element includes a pair of springs for each of the plurality of contacts that force the contacts into engagement with the contact pads but also allow the contacts to adjust for imperfections in the contact pad surface or the manufacturing tolerances of the contact pads or a support board that holds the contact pads.

The invention relates to a power tool and battery pack assembly including a battery pack for connection with the power tool to provide power for the operation of the power tool when connected thereto. The battery pack includes a plurality of power cells and connection means are provided to allow the selective supply of power at least a first or second voltage level to the power tool from the battery pack.

An electricity storage device includes a battery, a discharge device, and a controller for controlling charging and discharging of the battery. The discharge device includes a swelling member, a movable switch, and a discharge switch. When the swelling member swells, the movable switch is moved. When the movable switch is moved, the discharge switch is turned on. A signal indicating that the discharge switch is turned on is transmitted to the controller to cause the battery to start discharging of electricity.