Ultralow Temperature Glass Frit Encapsulation for Stable Dye-Sensitized Solar Cells

Hermetic encapsulation is crucial for the lifespan of dye-sensitized solar cells (DSSCs). Sealing with glass frits provides hermetic encapsulation and extends the lifetime of DSSCs yet so far has been performed at inconveniently high temperatures, above 300 °C, not compatible with most DSSCs materials. This study develops a new laser-assisted glass frit sealing process at low process temperature of 110 °C. For the first time, glass frit encapsulation becomes fully compatible with most heat-sensitive materials used in DSSCs and did not affect the device performance after sealing. Hermeticity and durability of the seal complies with MIL-STD-883 and IEC61646 standards. Unique glass frit sealing configuration, parameters of the laser beam, and sealing protocol are disclosed. The developed glass frit sealing is fully compatible with liquid junctions DSSCs based on iodine and cobalt mediators and the resulting devices showed 1000 h of stability under simulated solar light according to ISOS-L-2 testing conditions. The new low-temperature sealing method allows a simplified DSSCs fabrication with a fully hermetic and durable seal and extends the applicability of glass frit sealing to most types of the DSSCs devices.