Development of low cost faster-curing encapsulants for terrestrial PV modules

摘要

This research focuses on development of "faster-curing" EVA-based encapsulants. The implications of a successful development are significant, as reductions in process time increase a PV module manufacturing plant's rate of throughput and overall capacity. Allowing for lower -cost processing and gains realized by avoided cost of capital equipment, floor space, labor, etc., thereby reducing PV module manufacturing costs. Quantitative analysis of cure rate kinetics measured by Moving Die Rheometry determined that cure time reductions of ～70% were accomplished at 150°C, achieving full cure (crosslinking in excess of 80%), versus STR's commercial "fast-cure" 15295P EVA-based encapsulant. Prototype 60-watt polycrystalline silicon modules were manufactured using 5 and 6 minute lamination cycles in a Spire 240A laminator. Qualitative testing of EVA-based encapsulant samples processed during those trials suggests cure levels exceeding 80% crosslinking. The results to date, which are quite encouraging, are detailed including processing conditions, and current results from accelerated aging and qualification testing.