Adding Layers to Keep Cool......The researchers’ heat pump uses electrocaloric cooling, a phenomenon where certain materials temporarily change temperature in response to an electric field. Electrocaloric materials on their own, however, won’t produce a cooling effect that is large enough. They need to be paired with a transfer mechanism that continually moves heat. Rather than depending on a separate pump or actuator, which would add bulk and consume more energy, the researchers designed an elegant solution based on stacked layers of electrocaloric materials. The layers serve as a heat pump, moving warmth from the layer closest to the heat source away to the outermost layer. Kaur began exploring localized cooling technologies as part of a Berkeley Lab Laboratory Directed Research and Development (LDRD) award. One goal of the project, which began in 2022, was to optimize electrocaloric materials and enable their use in a wearable cooling device such as clothing or a blanket. An expert on thermal energy storage, Kaur teamed with principal investigator Qibing Pei, a professor of materials science and engineering at the UCLA Samueli School of Engineering, to explore the cooling potential of an electrocaloric material called poly (vinylidene fluoride-trifluoroethylene-chlorofluoroethy-lene) terpolymer, or P(VDF-TrFE-CFE). They published a paper with their colleagues last February which demonstrates that making this terpolymer film using a mix of solvents could achieve higher differences in temperature (i.e., more cooling) than typical synthesis methods. 

Liquid-Free Cooling.....Unlike most air conditioning units, the electrocaloric system does not rely on refrigerants or water. Using this kind of hyperlocal cooling can also save energy and reduce stress on the grid by keeping people cool while allowing for higher thermostat settings in buildings.......read on   https://newscenter.lbl.gov/2025/04/29/researchers-pioneer-heat-pumping-material-for-localized-cooling/