Application of multi-scale pore regulation for high thermal conductivity foam reinforcements in energy storage

[Display omitted] •The multi-scale pore regulation was conducted to reduce the low-λ areas inside foam reinforcement.•Thermal conductivity of the composite was significantly enhanced to 19.6 times higher than the matrix.•Finite element simulation revealed the mechanism of the multi-scale pore regulation on the overall heat transfer process.•A trade-off between the heat conduction enhancement and energy storage performance can be achieved by multi-scale pore regulation. A continuous diamond film layer was initially deposited on the surface of the foam skeleton by chemical vapor deposition (CVD), followed by the vertical growth of carbon nanotubes (CNTs) on diamond film using nickel particles as a catalyst. The CNTs extended into the interior of the pores inside the foam skeleton as a secondary heat transfer pathway. The effect of different pore densities on the thermal conductivity and latent heat of phase change composites (PCMs) was explored. The obtained diamond foam/carbon nanotube/paraffin composites (DF-CNT/PWs) was demonstrated to achieve an ultra-high conductivity of 5.3 W/m·K, which is 19.6 times that of the paraffin matrix. The latent heat of the DF-CNT/PWs is 83.37 J·g−1. In addition, finite element simulation confirmed that the thermal conductivity enhancer system could significantly improve the uniformity of heat transfer inside the foam skeleton.