A rechargeable bipolar lithium high-energy accumulator based on a novel electrochemical system was developed. The accumulator has a theoretical specific energy of 1070 Wh/kg, which is at the top of the range of all known battery systems. This bipolar high-energy accumulator will exceed the energy content of the known lithium ion battery. Compared with the conventional cell design, the bipolar accumulator design results in a low cell resistance, a low weight and small dimensions. The charge/discharge curves of a bipolar battery and its five single cells were discussed in this paper. It will be shown, that the cell with the lowest capacity determines the battery's behaviour. The chemistry of the inorganic electrolyte LiAICI(4) x 1.7 SO2 allows the overcharging of single cells. Laboratory samples can withstand a load of more than 200 mA/cm and combine a high specific energy up to 60 Wh/kg with a high specific power up to 2500 W/kg. (C) 2004 Elsevier B.V. All rights reserved.