Sandia’s Coatings and Surface Engineering, Packaging and Polymer Processing, and Organic Materials Science departments in the Materials Engineering Group have provided extensive support for the microsys­tems-enabled photovoltaic (MEPV) grand challenge laboratory-directed research and development (LDRD) project, which is now in its third and final year. Materials Engineering Group materials scientists, precision engineers, and technologists have made vital contributions to optical-component design, fabrication, and assembly—as well as to PV module final-level packaging—with impressive results.

Flexible photovoltaic module draped over a probe tip.

Flexible photovoltaic module draped over a probe tip.

For example:

  • Packaging and Polymer Processing Dept. personnel performed multiple-step assembly and packaging of several generations of MEPV prototype modules, with these modules incorporating two molded polycarbon­ate lenses, the silicon PV cells, a gorilla glass outer lay­er, and other components. These individual elements are adhesively bonded together and fully encapsulat­ed to provide a rugged, high-efficiency PV module.
  • The Materials Engineering Group team helped solve numerous optical design, materials compatibility, and materials assembly issues to properly account for important properties (coefficient of thermal expan­sion mismatches, graded refractive indices, etc.), and developed a set of materials selections (polydi­methylsiloxanes, thermoplastic polyurethanes, etc.) that allowed for void-free encapsulation using a specially designed vacuum lamination process.

The grand challenge LDRD principal investigator (Greg Nielson, MEMS* Technologies Dept.) reports that several institutions are interested in pursuing work with Sandia, including 3 seedling efforts that appear likely to receive follow-on funds to further raise the technology readiness level of this potentially world-changing solar-energy technology.

*  micro electro-mechanical systems