An electric energy storage device, comprising N energy units with a same rated voltage and provided with a socket, wherein the N energy units are equally divided into M energy modules. Each energy module comprises K energy units, wherein M2 and K2, and can be switched between parallel and series connection states. The disclosure also provides an electric tool system, wherein the electric tools with different rated voltages have different plugs, and the electric energy storage device outputs different voltages after connecting with the socket. The electric energy storage device with multiple output voltages can be suitable for electric energy storage devices with different rated voltages, and reduces the cost.

An electric energy storage device comprises four energy units with a same rated voltage and a socket. The four energy units are divided into two energy modules each comprising with two energy units. Each energy module is provided with a positive electrode and a negative electrode. The socket includes four voltage output terminals connected to the positive and negative electrodes of the two energy modules and is provided with two control parts, which respectively control the two energy units in the two corresponding energy modules to switch between parallel state and series state. An electric tool system is also provided, comprising a plug that is connected to the socket, and different plugs can connect the four energy units in different connection states. The electric energy storage device with multiple output voltages can be matched with various electric tools with different rated voltages, and reduces the cost.

A hand-held tool system includes a hand-held power tool, in particular a drill, having a wall device configured to be mounted on a wall to be processed by the hand-held power tool. The wall device includes at least a first sensor device that is configured to determine an orientation of the hand-held power tool relative to the wall device.

An electric energy storage device comprises four energy units with a same rated voltage and a socket. The four energy units are divided into two energy modules, each energy module is provided with two energy units, and each energy module is provided with a positive electrode and a negative electrode. The socket including four voltage output terminals respectively connected to the positive and negative electrodes of the two energy modules, and the socket is also provided with two control parts which respectively control the two energy units in the two corresponding energy modules to switch between parallel state and series state.

An electric energy storage device which includes four energy units with a substantially same voltage value is provided. 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 example device that may be mounted to a tool may include a clamping mechanism that allows the device to be put onto a tool and removed from the tool. The device may affix pieces and accessories by using an accessory fastening mechanism, such as one or more magnets. This device may include various features on a permanent or temporary basis. Such features may include lights, speakers, levels, or other features. In an example, the device may be used with a handheld tool, such as a power drill or other tool.

An electric energy storage device which includes four energy units with a substantially same voltage value is provided. 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.