Abstract:A series of key technologies to improve current efficiency of aluminum electrolytic cell were put forward and applied in 400 kA test electrolysis cell. The results show that cell voltage of experimental tank drops from 3.990 V to 3.702 V, current efficiency rises from 91.09% to 93.01%, average DC power consumption of ton aluminum drops from 13 135 kWh to 12 440 kWh after combination application of technologies of special-shaped cathode with bump structure, new anode with exhaust channel, widening steel bars and narrow gap welding, high conductive aluminum core composite anode steel claw and steel claw protecting ring, improving height of insulation material layer, and heat insulation groove cover.