Determination of the heat storage performance of thermochemical heat storage materials based on SrCl2 and MgSO4

Composite materials with salt hydrates are promising materials for thermochemical heat storage applications. Besides the determination of the isothermal heat of sorption of the storage materials, the temperature lift of a sorption process is a major key factor. The aim of this paper is the comparison of the heat of sorption with the temperature lift, measured in a laboratory-scaled storage. The measurements of the isothermal heat of sorption were taken by humidity controlled calorimetry. The materials for the investigations were salt pellets of SrCl2 and MgSO4 and composite materials that contain both salts. It could be found that SrCl2 has a high potential as an active substance in composite materials for thermochemical heat storage, due to a low temperature of dehydration and the reversibility of the dehydration and hydration. The host material for the salt hydrates was activated carbon, which has a strong influence on the kinetic of the sorption and the temperature lift, respectively.