Development and investigation of form-stable quaternary nitrate salt based composite phase change material with extremely low melting temperature and large temperature range for low-mid thermal energy storage

This paper reports a form-stable molten salt based composite phase change material (CPCM) owning extremely low melting point and large temperature range that can be promising candidate used in middle thermal energy storage fields. The was prepared by so-called cold compress hot sintering approach with eutectic quaternary nitrate of Ca(NO3)2-KNO3-NaNO 3-NaNO 2 as (PCM), MgO structure supporting (SSM) graphite conductivity enhancer (TCE). A series characterizations were carried out to investigate the microstructure, chemical compatibility properties well cycling stability. results show no reaction occurred among compositions salt, SSM TCEM before after sintering, indicating excellent physical composite. fairly around 89.56 °C relatively high decomposition 628 observed, giving density over 626 kJ/kg at 50–600 °C. mass loading 50% gives optimal formulation which 10% involved 1.4 W/m⋅ ∘C obtained. present indicate such could an effective alternative organic PCMs low-mid storage.