A promising radiative cooling composite coatings based on hydromagnesite mineral for dual thermal management in human body and lithium-ion battery

Radiative cooling emerges as an ideal solution to minimize the energy demand and environmental pollution associated with cooling applications. Herein, we report an industry-scalable radiative cooling technology capable of addressing the cooling demands from highly thermogenic sources by employing homemade hydromagnesite-based composites with excellent selective optical responses. First, relative to the pristine textile, the resulting radiative cooling textile modified by a hydromagnesite-polyacrylate (PA) composite coating possesses both high thermal emissivity (97.3 %) and solar reflectivity (90.2 %, and 95.5 % in the main solar waveband of 0.3–1.5 µm), which could cool the covered simulated skin by ∼ 2 and 10 ℃ in indoors and outdoors conditions, respectively. Second, when applied to lithium-ion battery, a temperature drop of 8.1 °C was realized when the battery was encapsulated by radiative cooling aluminum laminated film (ALF) modified with hydromagnesite-high-density polyethylene (HDPE) composites having an emissivity 92.6 %, thereby significantly improving its electrochemical behavior and operational performance, as well as safety by potentially avoiding the risk of a thermal runaway. The hydromagnesite-based composites also have good mechanical properties that are relevant to personal thermal management and lithium-ion battery cooling, enabling a substantial reduction in carbon emission and energy consumption associated with these cooling challenges.