The purpose of this study was to measure the thermal properties of ammonia borane and polyiminoborane with the transient plane source (TPS) method to analyze their applicability to heat storage systems. Tests results showed that the thermal diffusivity and thermal conductivity of ammonia borane increased as porosity of the samples decreased. Alternatively, both thermal properties of polyiminoborane increased with porosity, and thermal conductivity values were significantly lower than those obtained ...