(DE19827630-A1)   NOVELTY - Purification of electrolyte solutions for lithium (Li) cells comprises adding an adsorbent, consisting of a base fixed to a carrier, for chemical adsorption of protic impurities and separating the adsorbent.    USE - The electrolyte is used in secondary and primary Li batteries.    ADVANTAGE - Electrolytes prepared from very pure individual components normally contain protic impurities, e.g. water, alcohols and peroxides. The conductive salts are very sensitive to such impurities and decompose to e.g. hydrogen fluoride (HF), Li fluoride, phosphoryl fluoride, other phosphorus oxyfluorides and various oxyfluorophosphoric acids, which they attack the cathode and anode and greatly shorten the battery life. Conventional methods of reducing the water content are not effective enough, whilst addition of anhydrous halides and distillation to remove the hydrogen halide does not give optimum results. If HF is neutralized with a base, e.g. tributyl amine, the reaction product remains in the electrolyte and reduces the cycle efficiency. The present method is simple, quick and effective and can reduce the water and HF content to less than 30 ppm.    (EP1097485-A1)   NOVELTY - Purification of electrolyte solutions for lithium (Li) cells comprises adding an adsorbent, consisting of a base fixed to a carrier, for chemical adsorption of protic impurities and separating the adsorbent.    USE - The electrolyte is used in secondary and primary Li batteries.    ADVANTAGE - Electrolytes prepared from very pure individual components normally contain protic impurities, e.g. water, alcohols and peroxides. The conductive salts are very sensitive to such impurities and decompose to e.g. hydrogen fluoride (HF), Li fluoride, phosphoryl fluoride, other phosphorus oxyfluorides and various oxyfluorophosphoric acids, which they attack the cathode and anode and greatly shorten the battery life. Conventional methods of reducing the water content are not effective enough, whilst addition of anhydrous halides and distillation to remove the hydrogen halide does not give optimum results. If HF is neutralized with a base, e.g. tributyl amine, the reaction product remains in the electrolyte and reduces the cycle efficiency. The present method is simple, quick and effective and can reduce the water and HF content to less than 30 ppm.