Progress in corrosion and anti-corrosion measures of phase change materials in thermal storage and management systems

Phase change materials (PCMs) are widely used in thermal storage and management systems because of their high energy storage density and comprehensive phase change temperature range. In practical applications, the compatibility of PCMs is critical because PCMs are usually encapsulated in the vessel. It has been shown that PCMs are often corrosive to the vessel material and that this corrosiveness can be decisive for the lifetime of the thermal storage and management system. Currently, there are many studies on corrosion of materials in the chemical field and significant results have been achieved. However, the PCMs used for energy storage are less studied due to the dynamic environment of hot and cold alternation and the complex corrosion mechanism. Therefore, we have analyzed the corrosion behavior of PCMs in various operating conditions for its corrosion problem. The results show that inorganic PCM is generally more corrosive than organic PCM, and more scholars focus on the corrosion of inorganic PCM. Stainless steel is the most compatible metal with inorganic salts among common metal materials. Further, we also summarized some methods to avoid corrosion based on the current research results, such as adding anti-corrosive coatings, using corrosion inhibitors, and microencapsulating phase change materials. Finally, we predicted the future direction of corrosion protection, such as using amino acids containing heavy halogen atoms, which will be a promising corrosion inhibitor.