A comprehensive review of phase change film for energy storage: Preparation, properties and applications

Phase change film (PCF) has been extensively studied as a novel application form of energy storage phase change material (PCM). The emergence of PCF has made possible the application of PCM in highly flexible and space-constrained fields, which was hard to achieve before. Generally, in fields where energy output is more intensive and energy storage requirements are large, PCMs are commonly used in the form of blocks. However, conventional PCM blocks have the disadvantages of high volume share and weight, and increased thermal resistance due to mismatch with heat transfer elements. PCF has great potential for space-constrained applications due to its thinness and excellent mechanical properties, as well as its convenience for transportation and portability. This article reviews the progress of research on the preparation methods of PCF by a wide range of scholars in recent years and evaluates its advantages and disadvantages. It is crucial to choose the right method for different materials. In addition, the outstanding energy storage properties, thermal response properties and flexibility of PCF are summarized and analyzed. The unique thermal response characteristics that allow PCF to be applied in signal conveyance applications are a key factor in its preference. Furthermore, the potential applications of PCF in the field of energy storage such as body bending wearable devices, thermal management of microelectronic devices, building energy saving and solar energy are also detailed. Finally, the future development of PCF is discussed in four aspects: sustainable development, optimization of preparation process, refinement of performance evaluation system and enhancement of thermal property. Notably, this review integrates energy storage materials PCM from the viewpoint of application forms for the first time, which provides certain reference significance for subsequent studies.