Development of flexible phase-change heat storage materials for photovoltaic panel temperature control

Photovoltaic (PV) power generation technology plays a crucial role in achieving humanity’s long-term sustainable development goals and has been widely utilized worldwide. However, the efficiency of PV cells is affected by temperature fluctuations, and enhancing energy conversion efficiency can be achieved by reducing the surface temperature of PV panels. Inorganic phase change materials offer advantages such as a high latent heat of phase change, excellent temperature control performance, and non-flammability, making them highly promising for applications in solar energy storage and thermal management. Practical applications of inorganic phase change materials are hindered by issues such as high rigidity, susceptibility to fracture, and unstable shape. To address these issues, this paper combines optimized disodium hydrogen phosphate dodecahydrate (DHPD) with sodium polyacrylate (PAAS) and starch (ST) to prepare a new type of PAAS/ST/DHPD flexible phase change hydrogel. The phase change temperature is 31.0 °C, with a latent heat of change of 162.3 J/g when the DHPD content is 65 wt%. Furthermore, the hydrogel demonstrates excellent thermal stability after 100 heating–cooling cycles and exhibits good compression-resilience properties at both 25 °C and 40 °C. The study also evaluates the cooling effect of the composite material on PV panels, showing a significant reduction in panel temperature and promising application prospects.