Large Area Via-Enabled Back Contact Thermophotovoltaic Cells for a High Power Density System

Commercialization of thermophotovoltaic (TPV) cells and applications requires not only good efficiencies, but high power output, the two of which may be independent. Back contacted cell architectures have the potential to improve the power output of a TPV system through reduced series resistance, metal shading, and dead area between cells in the array. We have designed and fabricated large-area back-contacted TPV cells for integration into a portable-scale TPV power generator. We tailor the design to the high-current application and the practicality of packaging of cells into a cylindrical array. It enables over 15% improved system power output. We fabricate cells in a process featuring wet-etching of vias, achieving high power output and a one-sun open circuit voltage over 450 mV. This architecture and fabrication process could be applied to optimal bandgap material or multijunction cells for further increase in power output.