相变微胶囊集成于光伏电解系统以增强太阳能制氢性能

Abstract Passive thermal management is a critical yet underexplored approach for enhancing the efficiency and scalability of photovoltaic-electrolysis (PV-EC) systems for solar hydrogen production. In this study, a cured phase change material (PCM) interfacial layer was integrated into a PV-EC system to regulate PV temperature and enhance hydrogen output. Typically, paraffin@silica microcapsules were synthesized and embedded in a polydimethylsiloxane (PDMS) matrix to form a thermally conductive composite capable of passively regulating the operating temperature of the PV module. Among the synthesized variants, microcapsules with a core-to-shell ratio of 1:1.5 demonstrated superior thermal stability and encapsulation performance. Experimental results indicated that the composite with a microsphere-to-PDMS mass ratio of 0.3 and a thickness of 5 mm achieved the maximum PV temperature reduction of 14.4 °C. Nevertheless, the composite with a mass ratio of 0.2 and a thickness of 3 mm offered the optimal trade-off between thermal regulation and electrical performance. Based on these findings, a system-level PV-PCM-EC model was developed. The model comprised a 100-cell PV array arranged in 50 parallel strings of two series-connected units, and a three-unit proton exchange membrane (PEM) electrolyzer array. The optimized system achieved a solar-to-hydrogen efficiency of 22.2 %, representing a 9.9 % improvement over the uncooled baseline. These results underscore the potential of integrated PCM composites as an effective and scalable passive thermal management strategy for PV-PCM-EC solar hydrogen production systems.