Research progress in molten nitrate salts for thermal energy storage

doi:10.3969/j.issn.2097-0706.2025.12.002

Abstract

Abstract:

With the advancement of the "dual carbon" goals， the importance of thermal energy storage technology has become increasingly prominent. As an ideal thermal storage material， molten salts have gained significant attention in the medium- and high-temperature heat transfer and storage fields. Molten nitrate salts， in particular， exhibit unique advantages that lead to widespread applications across various fields. Recent research on the issues of insufficient thermal storage performance and strong metal corrosiveness in molten nitrate salt systems is reviewed， with a detailed overview of methods to improve the thermal storage performance of molten nitrate salts from two aspects： the development of multi-component molten nitrate salt systems and the doping of nanomaterials. Additionally， the impact of impurity ions on molten nitrate salts is discussed from the perspectives of thermal properties and corrosion. Research indicates that multi-component molten nitrate salt systems and doping with nanomaterial can substantially enhance thermal storage performance of molten salts. However， the presence of impurity ions negatively affects their performance. Future research could focus on the development of novel molten nitrate salt systems， the synergistic enhancement mechanism of nanoparticles， the combined effects of impurity ions on corrosion behavior， and the development of online detection technologies to further improve molten salt thermal storage technology.

Key words: molten nitrate salt, molten salt heat storage, thermal energy storage, thermophysical properties, nanomaterials, impurity ions, renewable energy, energy storage

CLC Number:

TK02

JIANG Zeling, XIONG Yaxuan, BAI Yinlei, GENG Bochen. Research progress in molten nitrate salts for thermal energy storage[J]. Integrated Intelligent Energy, 2025, 47(12): 14-24.

Figures/Tables 8

Table 1

Novel multicomponent molten nitrate salts and their thermophysical properties

新型硝酸熔盐	熔点/℃	分解温度/℃	比热容/[J·(g·K)^-1]	文献
$50 % M g (N O 3) 2$ $- 50 % N a N O 3$	355.40	440.00	1.023	[28]
$60 % A l (N O 3) 3$ $- 40 % C u (N O 3) 2$	65.00	215.00	2.729	[29]
$32 % C a (N O 3) 2$ $- 24 % N a N O 3$ $- 44 % K N O 3$	80.00	600.00	1.500	[30]
$N a N O 3$ $- K N O 3$ $- N a N O 2$ $- 15 %$ $- 30 % L i N O 3$	77.50~94.37	612.00~639.11	1.860~1.950	[31]
$10 % N a N O 3$ $- 60 % K N O 3$ $- 20 % C a (N O 3) 2$ $- 10 % N a N O 2$	130.20	650.00		[32]
$6.67 % C a (N O 3) 2$ $- 44.17 % K N O 3$ $- 5.83 % N a N O 3$ $- 33.33 % N a N O 2$	83.10	628.50	1.520	[33]
$20.5 % N a N O 3$ $- 11.5 % K N O 3$ $- 12 % C a (N O 3) 2$ $- 16.5 % N a N O 2$ $- 39.5 % K N O 2$	102.30	651.20	1.500	[34]

Table 1

Fig.1

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Fig.7

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