A review of domestic and international research progress on phase change materials (PCM) for cold thermal energy storage in air-conditioners is presented in this paper. The performance requirements and basic classification of PCMs are briefly introduced. The shortcomings of existing PCMs for cold thermal energy storage in air-conditioners are summarized and recent approaches to optimize the properties of PCMs are discussed

especially to remedy the supercooling and phase separation of inorganic materials

as well as the poor thermal conductivity of organic materials. The advantages and disadvantages of inorganic and organic phase change materials in cold thermal energy storage were compared and recommendations for future research and development directions of PCMs for cold thermal energy storage in air-conditioners were proposed. This paper focuses on materials for room-temperature air-conditioning. It equally conducts an in-depth investigation and review of typical materials

which provides a basis for improving the properties of PCMs and promoting their practical applications.