Phase-change Material - Selection Criteria

Selection Criteria

• Thermodynamic properties. The phase change material should possess:
  1. Melting temperature in the desired operating temperature range
  2. High latent heat of fusion per unit volume
  3. High specific heat, high density and high thermal conductivity
  4. Small volume changes on phase transformation and small vapor pressure at operating temperatures to reduce the containment problem
  5. Congruent melting

• Kinetic properties
  1. High nucleation rate to avoid supercooling of the liquid phase
  2. High rate of crystal growth, so that the system can meet demands of heat recovery from the storage system

• Chemical properties
  1. Chemical stability
  2. Complete reversible freeze/melt cycle
  3. No degradation after a large number of freeze/melt cycle
  4. Non-corrosiveness, non-toxic, non-flammable and non-explosive materials

• Economic properties
  1. Low cost
  2. Availability