Research Progress on the Phase Change Materials for Cold Thermal Energy Storage

Abstract

Thermal energy storage based on phase change materials (PCMs) can improve the efficiency of energy utilization by eliminating the mismatch between energy supply and demand. It has become a hot research topic in recent years, especially for cold thermal energy storage (CTES), such as free cooling of buildings, food transportation, electronic cooling, telecommunications cooling, etc. This paper summarizes the latest research progress of the PCMs-based CTES. Firstly, the classification of PCMs for low temperature storage is introduced; the thermal physical properties (e.g., phase change temperature (PCT) and latent heat) of suitable PCM candidates (−97 to 30 °C) for CTES are summarized as well. Secondly, the techniques proposed to enhance the thermal properties of PCMs are presented, including the addition of nanomaterials, the microencapsulation and the shape stabilization. Finally, several representative applications (−97 to 65 °C) of PCMs in different CTES systems are discussed. The present review provides a comprehensive summary, systematical analysis, and comparison for the PCMs-based CTES systems, which can be helpful for the future development in this field.

Supercooling suppression in the tetrahydrofuran clathrate hydrate formation

“…1,2 With the demand for efficient and environmentally friendly transportation/distribution systems, latent heat storage technology has drawn attention. 3 An example of applications is cold transportation of fresh foods and medical vaccines, in which a latent heat storage material is packed and kept cold to maintain freshness and effectiveness. 4,5 Since it is not necessary to carry refrigeration equipment simultaneously, it achieves weight reduction and distribution cost reduction.…”

“…[4][5][6] Latent heat is the thermal energy required for the phase change of a substance and is larger than sensible heat. 3 Latent heat storage technology uses latent heat at another time or in another place. For example, the cold storage material is cooled and crystallized in advance, and the latent heat is used to cool the object and keep it fresh.…”

“…For example, the cold storage material is cooled and crystallized in advance, and the latent heat is used to cool the object and keep it fresh. [3][4][5][6] There are significant properties desired for cold storage materials. One is the cooling temperature (evolution temperature of latent heat) desired for the object.…”

“…The other is the enthalpy (amount of latent heat) of phase change, which is proportional to the cold storage duration. [3][4][5][6] Specifically, the cold storage temperature is around 283 K for fresh fruits and vegetables, 283 K or less for meats, 278 K or less for fresh seafood, and 281 K or less for medical vaccines. [7][8][9] It is not preferable to use ice for keeping them cold because the melting temperature of ice is too low.…”

Preparation and Performance of n-Dodecane Microencapsulated Phase Change Cold Storage Materials

“…Due to their energy storage properties, PCMs are widely used in various energy storage applications such as buildings [15], air conditioners and refrigerators [16], electronic components [17], industrial waste heat recovery [18], cold-chain storage and transport [19], heat transfer fluids [20], and solar energy [21]. PCMs can be divided into inorganic, organic and composite according to the chemical properties of the constituents [22][23][24]. Among these three PCM types, the organic ones are favoured by researchers for their low supercooling, low propensity to phase separation, low corrosiveness, stable physico-chemical properties and good solid-state formability [25,26].…”