Wiederaufladbare Lithiumbatterie mit anorganischer Elektrolytlösung

At the FhG-Institute for Chemical Technology a new battary system Li/inorganic electrolyte/LiCoOsub2 is examined with a high theoretical specific energy of 1070 Wh/kg. The main problem of rechargeable lithium batteries with organic electrolyte solution is the low cycling efficiency of lithium. The inorganic electrolyte solution is a well conducting clear liquid, which is applicable from -25 to ca. 70 degree Celsius. In this work lithium cycling efficiencies higher than 99 percent at 40 mA/qcm were obtained. Potentiodynamic cycling of the LiCoOsub2 electrode between 3.5 and 4.5 V vs. Li/Lihighplus showed a loss of capacity of 0.3 percent per cycle. At potentials higher than 4.2 V chlorine is generated in a side reaction without any loss of capacity up to 5 V. Clsub2 and AlClsub3 are reacting according to a shuttle mechanism with Li or LiCl to form system compatible products. In order to determine the volatile products a special Dems-apparatus was constructed which allowed the unambiguou s detection of chlorine generation at a nickel electrode.