Effect of nucleating agent on the thermal storage performance of Ba(OH)2 8H2O as a phase change material

Ba(OH)2 8H2O is one important Phase Change Material (PCM), but its usage is restricted by its large supercooling degree. In this work, several nucleating agents were tested to improve its thermal storage performance: BaSO4, BaCl2 2H2O, Na2B4O7 10H2O and Na2HPO4 12H2O. The test was done by a melt-solidification heating cycle experiment. The results show that all these nucleating agents can inhibit the supercooling characteristics of Ba(OH)2 8H2O. More important, the Differential Scanning Calorime (DSC) test indicates that BaCl2 2H2O can be used as one suitable nucleating agent since the Ba(OH)2 8H2O/BaCl2 2H2O composite can keep higher latent heat. With BaCl2 2H2O as the nucleating agent and sodium carboxymethylcellulose (CMC) as thickener, the Ba(OH)2 8H2O composite possesses a smaller supercooling degree and can maintain a favourable thermal storage performance.