Abstract: The invention relates to a fuel cell stack comprising a plurality of identical bipolar plates (12), stacked in a stacking direction. Each bipolar plate is formed by two monopolar plates, which are placed one on top of the other and which together form at least one pocket at one end of the bipolar plate. Each pocket having an end opening configured to receive a pin of a fuel cell measurement module, any two successive bipolar plates being stacked head-to-tail.

Abstract: Ladle for the filtration of a liquid metal such as aluminum, magnesium, and their alloys over a filter medium of the gravel bed type. The ladle comprises a chamber in which the filter medium rests on a supporting grid, an inlet for supplying liquid metal to the chamber and an outlet for removing liquid metal from the chamber. The ladle includes first and second heaters for heating the liquid metal, the first heater being located outside the filter medium and the second heater being an electrical immersion heater which is located in the inlet or outlet and adjacent the filter medium. The second heater is arranged for immersion in liquid metal flowing through the inlet or the outlet.