Electrolysis cell for a molten electrolyte

An electrolyte cell for the production of a metal by electrolysis of a molten electrolyte which is more dense than the metal, comprising,

• an electrolysis chamber 16 including at least one electrode assembly of a anode 24 having a major face and also at least one other face selected from an end face and a bottom face, one or more intermediate bipolar electrodes 28, 30, 32, 34 arranged facing not only the major face of the anode but also at least one other face of the anode, and a cathode 26 having a front face facing an intermediate bipolar electrode and a back face, the electrodes defining electrolysis regions between them, and a gas collection space 44 above the assembly,
• a metal collection chamber 18 in communication with the top and bottom of the electrolysis regions, but screened from the gas collection space,
• a duct 20 defined by the back face of the cathode and leading to the metal collection chamber and to the gas collection space to cause gas to separate and electrolyte/metal mixture to flow to the metal collection chamber,
• the one or more intermediate bipolar electrodes having top edges arranged to permit electrolyte/metal mixture rising from the electrolysis regions to spill out over the bipolar electrodes and cathode and into the duct,
• and means 22, for maintaining the surface of the electrolyte/metal mixture at a substantially constant level.