As a common room temperature inorganic hydrated salt phase change material(PCM)

calcium chloride hexahydrate(CaCl2·6H2O) is being widely focused due to its low cost

easy availability and high thermal energy storage. CaCl2·6H2O was prepared in terms of mass ratio of anhydrous CaCl2 and H2O as 1.027:1

whose crystal structure was characterized by X-ray diffraction(XRD). CaCl2·6H2O was modified by adding nucleating agents SrCl2·6H2O and Ba(OH)2. The results showed that the combination of SrCl2·6H2O and Ba(OH)2 could suppress supercooling phenomenon. The average supercooling degree was 1.07℃ in the process of melting-cooling for 10 cycles. The phase change latent heat of CaCl2·6H2O before and after adding nucleating agents

characterized by differential scanning calorimetry(DSC)

decreased from 223.54 J·g-1 to 160.41 J·g-1. In order to enlarge the scope of phase change temperature of CaCl2·6H2O

5%

10%

15%

20% and 25%(mass) magnesium chloride hexahydrate(MgCl2·6H2O) was added into CaCl2·6H2O respectively

which indicated the phase change temperature of CaCl2·6H2O decreased linearly with the increase of MgCl2·6H2O content

however

not exceeding 20%(mass). The modification of CaCl2·6H2O-20% MgCl2·6H2O binary eutectic salt phase change thermal energy storage material was designed by adding 1% SrCl2·6H2O and 0.5% CMC

and the results suggested that the degree of supercooling was reduced to 0.57℃. The phase change latent heat of this material was 141.09 J·g-1

which was lower than that of CaCl2·6H2O(223.54 J·g-1) and MgCl2·6H2O(163.35 J·g-1). The above study showed that inorganic hydrated salt CaCl2·6H2O had significant application value as an inorganic PCM.