The present invention describes an electrochemical half-cell, comprising a gas space, an electrolyte space and a gas diffusion electrode in the form of a cathode or anode. The gas diffusion electrode separates the gas space from the electrolyte space and comprises an electrically conductive substrate and an electrochemically active coating. The gas diffusion electrode includes a coating-free edge region and is connected to a support structure in the coating-free edge region via an electrically conductive plate, which covers at least the coating-free edge region as well as a coated edge region.