UC Riverside

Temperature rise in multi-junction solar cells reduces their efficiency and shortens their lifetime. In this thesis research, I investigated the feasibility of using noncuring graphene-enhanced thermal interface materials for passive thermal management of concentrated multi-junction solar cells. Using an inexpensive scalable technique, graphene and few-layer graphene fillers, with varying concentrations, were incorporated in the noncuring mineral oil matrix. The graphene filler loading of up to 40 wt% has been used. The thermal interface material was applied between the solar cell and the heat sink. The performance parameters of the solar cells were tested using an industry standard solar simulator with concentrated light illumination of up to 200× suns. For comparison, commercial thermal interface material was also tested. It was found that the noncuring graphene enhanced thermal interface material substantially improves the photovoltaic cell’s open circuit voltage. The improvement is achieved via a reduction in the cell’s temperature under concentrated sun. The performance of the noncuring graphene thermal interface material was better than that of the commercial reference sample. The obtained results in this thesis are important for the development of the thermal management technologies for the next generation of photovoltaic solar cells.