A motor vehicle key of flat structure includes a circuit board with an opening, a mounting for a battery, wherein the mounting extends at least partially over the opening, and contact elements, which are electrically coupled to the circuit board. One contact element includes a resilient contact section, by means of which the battery may be fixed in the position in the mounting. The contact element is fastened to the circuit board such that a region of the resilient contact section extends over the opening above a plane defined by the surface of the circuit board and at least this region is received in the opening when the battery is disposed in the mounting and is fixed in position in it by the resilient contact section.