Different salt mixtures have been compared with the respective pure salts for the hydration and dehydration behavior. In case of the combination CaCl2/MgC2, mixing of salt hydrates shows promising behavior. Calcium chloride and magnesium chloride only showed cycle stability by control of the hydration terms. Surprisingly the mixture of calcium chloride and magnesium chloride showed good cycle stability without reaction control to prevent overhydration. Also the mixture shows superior kinetic properties. Further investigation will be performed to identify further synergies, ideal mixing ratio and the phases which are formed. The most promising compounds will be tested for the preparation of composites.