Experimental and numerical investigation on dodecane/expanded graphite shape-stabilized phase change material for cold energy storage

Using cold latent heat thermal energy storage (LHTES) in cold chain logistics can improve the energy efficiency. In this study, a shape-stabilized phase change material (PCM) with dodecane as PCM and expanded graphite (EG) as skeleton was developed firstly. The optimal content of EG in composite was confirmed as 16 wt% by heat treatment and DSC testing. The DSC testing results show that dodecane/EG shape-stabilized PCM has a phase change temperature of −9.67 °C and latent heat of 151.7 J/g. The microstructure of the dodecane/EG was characterized by SEM, FT-IR and specific surface area analyzer, and the results show that the dodecane was uniformly stuffed in the pore structure of EG under physical action. Thermal conductivity of the dodecane/EG is 15 times higher than that of dodecane. And the thermal conductivity enhancement of the composite PCM was also verified by the thermal performance test. Moreover, a numerical model of passive storage system with the dodecane/EG PCM was established and the simulation results are highly matched with the experimental result. In conclusion, the prepared dodecane/EG with noticeable thermal permeance and form stability and can be further applied in cold LHTES. •EG prevents leakage and improves thermal conductivity of dodecane synergistically.•Thermal conductivity of composite PCM is 15 times higher than that of dodecane.•A numerical model of passive TES system loaded dodecane/EG is established.•Simulation results have a great agreement with the experimental results.