But not much is known about the mechanism that links all those tiles together to create the actual solar roof other than Elon Musk saying that there’s a “shocking amount of technology in the connectors.”
Now a new patent explains in more detail a method that the company invented to connect the tiles.
CBInsight first spotted the patent and linked it to the solar roof.
The patent was granted to Tesla yesterday after SolarCity filed for it on May 24, 2016, before Tesla acquired the company.
The abstract of the invention is not the most simple to understand:
“One embodiment can provide a system for curing conductive paste applied on photovoltaic structures. The system can include a wafer carrier for carrying a plurality of photovoltaic structures and a heater. The wafer carrier can include a surface element that is in direct contact with the photovoltaic structures and is substantially thermally insulating. The heater can be positioned above the wafer carrier. The heater can include a heated radiation surface that does not directly contact the photovoltaic structures.”
Basically, the system binds the cells in a “cascade” formation with a conductive adhesive that is activated by heat.
Here a few images from the patent application (which is embedded in full below) to help visualize it:
The bonding system both enables to physically link the solar tiles together and conductivity between them.
Tesla believes this system is good for durability, which will be needed based on the “infinity warranty” that they are offering, and for the installation process, which represents a significant part of the cost of solar and roofing in general.
The inventors wrote in the patent application:
“In some embodiments, the edge-overlapped strips can be heated for a duration between 10 and 100 seconds, depending on the temperature and thermal design of the heater, as well as the thermal design of the wafer carrier. A well-designed system that can efficiently heat the strips without damaging the photovoltaic junctions can reduce the time needed for curing the conductive paste to a period between 25 and 60 seconds.”
It’s not clear if it is the method that they are now using since the product could have evolved since they applied for the patent last year.
Earlier this month, Tesla disclosed that they started solar roof installations at home of CEO Elon Musk and other employees. There is still no word on when regular customer installations will start.
Here’s the patent application in full: