What’s PCMs(Phase Change Materials)? Phase change materials are kind of material which can absorb or release heat when the shape of the material changes, but the temperature of the material itself does not change. Because of its huge latent heat of phase change, it has the function of temperature control, energy storage and thermal protection. Water is the most common phase change material. When the temperature is below 0 ° C, water changes from liquid to solid (Freeze). When the temperature is higher than 0 ° C, water changes from solid to liquid (...