A Novel Coverglass System with Enhanced Radiation Resistance

The Foster-Miller team is developing a novel coverglass system that protects photovoltaic cells on space power systems that are exposed to high doses of ionizing radiation. The spectrum of radiation a solar cell is exposed to not only provides usable energy, over time it also reduces the efficiency of the cell by darkening the barrier coverglass, escalates the operating temperature, and deteriorates adhesives that hold the array together. Foster-Miller’s new coverglass will prolong the system’s end of life by preventing the harmful effects of ionizing radiation and UV radiation while allowing the power generating wavelengths to be transmitted to the photovoltaic cells. Our approach incorporates alternative types of host glass doped with radiation hardening additives. The glass will accommodate increased amounts of radiation absorbing dopants that provide concurrent oxidation and reduction pathways. Further, the new glasses can be engineered to broaden band gaps and so further enhance performance of modern, high-efficiency multijunction solar cells. (P-050060)