Research progress of low-grade energy chemical heat storage materials

Compared with the apparent/latent heat storage, chemical heat storage utilizes reversible chemical changes to absorb and release energy and its energy density increase drastically by orders of magnitude. In this paper, based on the premise of low-grade energy utilization, chemical heat storage has been divided into two categories: chemical sorption heat storage and chemical reaction heat storage. In addition, the principles, characteristics, existing problems and application development trend of the widely studied or having application prospect chemical heat storage materials have been discussed and summarized. Through the analysis and comparison of different pure materials, it is found that salt hydrates can be used as a kind of ideal chemical heat storage materials, but they also have disadvantages such as deliquesce. However, the formation of composite materials can provide an effective solution to overcome the disadvantages of various pure materials. In addition, there is still lack of chemical heat storage materials which can work well in reactor. Finally, this paper has pointed out some possible problems to be solved in the future and the further research direction in the selection of chemical heat storage materials. © 2020, Chemical Industry Press Co., Ltd. All right reserved.