PCMs, Phase Change Materials, such as water, paraffin, salt hydrates, etc. are able to absorb, store and release large amounts of heat or cold at comparatively small temperature change by changing their physical state, as for example from solid to liquid, solid to solid or through evaporation of the storage material. The heat stored is called latent heat, therefore materials are also referred to as “LATENT HEAT STORAGE MATERIAL”.
PCMs with a solid-liquid phase change are most commonly used, also in construction and building applications .
It’s as simple as the ice cube melting in your drink: When ice cubes melt in a drink, they absorb heat from their environment without increasing their temperature and so keeping the drink cool.