Sea urchin skeleton-inspired triply periodic foams for fast latent heat storage

The latent heat storage technology has been widely applied in various thermal management fields, but its extensive deployment is limited due to the poor thermal conductivity of phase change material. Here, inspired by the microstructure and functions of sea urchin skeleton, four different metal foam skeletons based on triply periodic minimal surface (TPMS) are introduced to enhance latent heat thermal energy storage performances, which are evaluated by both experiment and numerical simulation. The metal foam-PCM (MFPCM) based on the Primitive structure has the fastest thermal energy storage rate with melting time prominently reduced by 20% compared to the traditional structure (Lattice). The underlying mechanism can be attributed to a more continuous and compact internal structure of TPMS compared with traditional MFPCM by thermal resistance analysis. In addition, the effect of gradient porosity is investigated as well, and the positive gradient in porosity has the fastest melting rate. The present study provides a new idea to design high-performance MFPCM and promotes the application of bionics in accelerating latent heat thermal energy storage.