ULTRA-COMPACT COOLING SYSTEMS BASED ON PHASE CHANGE MATERIAL HEAT-RESERVOIRS

A cooling system includes a first stage heat reservoir arranged to absorb heat from a heat source. Heat is transferred from the first stage heat reservoir to a second stage heat reservoir. The first stage heat reservoir includes a material with a heat capacity lower than that of the second stage heat reservoir but with a thermal conductivity higher than that of the second stage heat reservoir. Heat transfer structure increases heat transfer rate from the first stage heat reservoir to the second stage heat reservoir.