US Patent 7776191 Cathhodes for aluminum electrolysis cell with non-planar slot configuration

Cathodes for aluminum electrolysis cells are formed of cathode blocks and current collector bars attached to those blocks. The cathode block has a cathode slot for receiving the collector bar and has a higher depth at a center than at both lateral edges of the cathode block. Additionally, the collector bar thickness is higher at the center than at both lateral edges of the cathode block. This cathode configuration provides a more even current distribution and, thus, a longer useful lifetime of such cathodes and increases cell productivity.