The invention relates to a test stand for a fuel cell stack comprising an insulating device for thermally insulating the fuel cell stack, a media supply device for supplying a gaseous fuel and an oxidising agent to the fuel cell stack and an electronic control device for controlling andor regulating as well as for monitoring a test method. According to embodiment, a reflection channel module including a grin lens and a bandpass filter is employed to transmit the optical with a particular wavelength and reflect all other channel signals. An insert valve is mounted within the cavity, forming a seal with the inside wall. Then, third and fourth electrical contact arms come in contact with fourth and fifth electrical contact pads, by which red-eye reduction device is activated. The compound of nitrogen reduces noise in read data from the tunneling magnetoresistance transducer. If overcharging, for instance, generates an overpressure inside the battery, the battery shell bulges and tears the conductive strip in two starting at the slit.