SYSTEM, INTERFACE, POWER TOOL AND ENERGY SUPPLY DEVICE

A system including a power tool and an energy supply device, wherein the power tool can be detachably connected to the energy supply device via an interface. The interface has a base material with a first density and is designed in such a way that the interface allows a relative movement of the power tool and the energy supply device in an insertion direction and prevents a relative movement between the power tool and the energy supply device in the other spatial directions. The energy supply device has a first contact region with a first contact material and the power tool has a second contact region with a second contact material, wherein the first contact material and/or the second contact material have a second density, wherein the second density is greater than the first density of the base material of the interface. An energy supply device, and to a corresponding interface is also provided.