A novel PCM of lauric–myristic–stearic acid/expanded graphite composite for thermal energy storage

•A ternary eutectic mixture of lauric–myristic–stearic acid (LA–MA–SA) was prepared.•The composites PCM of LA–MA–SA/EG (expanded graphite) were fabricated.•The optimum absorption ratio of LA–MA–SA to EG is 12:1 (W/W).•The thermal conductivity of LA–MA–SA/EG was much higher than that of LA–MA–SA.

In this paper, a novel composite phase change material (PCM) of lauric–myristic–stearic acid ternary eutectic mixture/expanded graphite (LA–MA–SA/EG) (12/1, W/W) was prepared. It was characterized by SEM, FT-IR and DSC. The results indicated that LA–MA–SA uniformly distributed in the porous network structure of EG, the melting and freezing temperatures and latent heats of the composite PCM were 29.05 °C and 29.38 °C, and 137.1 J/g and 131.3 J/g respectively. The thermal conductivity of LA–MA–SA/EG was much higher than that of LA–MA–SA, which is also verified by thermal performance test. Thermal cycling test results showed LA–MA–SA/EG had a good thermal reliability after 1000 thermal cycles. All results indicated that the prepared LA–MA–SA/EG composite PCM has suitable thermal properties for thermal energy storage applications such as energy buildings, condensation heat recovery.