To find a medium temperature phase change heat storage material with high thermal conductivity and heat storage ability, expanded graphite (EG) with high thermal conductivity is used as the carrier material, and the binary mixed molten salt of 88 wt% LiNO₃–12 wt% NaCl is used as the phase change material (PCM). EG and PCM are uniformly dispersed by ultrasound crushing method. To get the right EG addition ratio, LiNO₃–NaCl/EG composite PCMs (LNE) with EG mass ratio of 10 %, 15 %, 20 %, and 30 % are prepared by static melt adsorption method. The melting point, phase change enthalpy and other parameters of the composite material are tested and analyzed. The experimental results show that the melting temperature and the phase change enthalpy of LNE gradually decrease with the increase of EG mass proportion. For all LNE samples, the adsorption ratio of PCM exceeds 90 % to 95 %. The thermal conductivity of the PCM greatly improves with the increase of EG mass proportion. The thermal conductivity of the composites with 15 wt% EG is 6.532 W·m⁻¹·K⁻¹, which is about 3.7 times that of the binary mixed molten salt. The thermal conductivity increases with the increase of the apparent density. The composite PCM has stable performance. The 85 wt% LiNO₃–NaCl/15 wt% EG composite PCM has the best overall performance.

为寻找具有高导热性和蓄热能力的中温相变蓄热材料，以高导热性膨胀石墨（EG）为载体材料，以88 wt% LiNO ₃ –12 wt %的二元混合熔盐为研究对象。% NaCl 用作相变材料 (PCM)。EG和PCM通过超声粉碎法均匀分散。为了获得正确的 EG 添加比例，LiNO ₃通过静态熔体吸附法制备了EG质量比为10%、15%、20%和30%的NaCl/EG复合PCMs（LNE）。对复合材料的熔点、相变焓等参数进行了测试分析。实验结果表明，随着EG质量比例的增加，LNE的熔化温度和相变焓逐渐降低。对于所有 LNE 样品，PCM 的吸附率超过 90% 到 95%。随着EG质量比例的增加，PCM的热导率大大提高。含 15 wt% EG 的复合材料的热导率为 6.532 W·m ^-1 ·K ^-1，约为二元混合熔盐的3.7倍。热导率随着表观密度的增加而增加。复合PCM性能稳定。85 wt% LiNO ₃ –NaCl/15 wt% EG 复合 PCM 具有最佳的整体性能。