LATENT HEAT STORAGE DEVICE WITH PHASE CHANGE MATERIAL AND GRAPHITE MATRIX

A latent heat storage device is formed with a carrier substrate formed of expanded graphite material. Phase change material is infiltrated in the graphite material. A thin graphite sheet provides for the functional heat conductivity into and out of the carrier substrate. After the phase change material (PCM) is infiltrated in the carrier substrate, a density of the infiltrated carrier substrate exceeds its starting density by a ratio of at least 3:1 or 4:1 or more. The volume dimensions of the infiltrated the carrier substrate remain substantially unchanged. In the alternative, the latent heat storage device may also have a PCM coating layer on a thin carrier substrate, wherein the phase change material is interspersed in a carrier matrix forming the PCM coating layer. The composite device may be very thin.