Shy Organic Photovoltaics: Digitally Printed Organic Solar Modules With Hidden Interconnects

Abstract

One of the biggest attractions of the organic photovoltaics (OPV) technology is the easiness with which it can be integrated. However, despite its semitransparency and wide variety of colors, a major unresolved challenge is to fabricate optically inconspicuous organic photovoltaic modules (OPV‐M) that can be integrated into visually demanding products. This is dominantly due to the visual obstruction from Z‐interconnection lines inherent to module processing with classical patterning methods. We now present for the first time a solution to this problem, which utilizes a visually seamless interconnection method to elegantly minimize the conspicuity of the interconnection regime. We realize such invisible interconnects by inkjet printing highly conductive silver lines, which penetrate the solar cell stack and form an electrical connection between adjacent cells. A combined characterization approach utilizing in‐depth electrical characterization and finite element (FEM) simulation rationalizes the excellent electrical cell‐to‐cell contact established with this interconnection technology. We combine this technology with a variable‐geometry module design into an innovative digital inkjet printing platform for the production of state‐of‐the art but visually attractive solar modules. The full potential of this concept is demonstrated by a fully inkjet printed arbitrarily shaped OPV‐M portrait.

Material Strategies to Accelerate OPV Technology Toward a GW Technology

“…[8,9] Alternative interconnection architectures are outlining a good compromise between record GFF values and a probably easier to scale "one step interconnect" (OSI) process. [10][11][12] But even with industrial ns laser patterning, GFFs of more than 90% are obtained for large area modules. As such, one would expect to see an active area module performance which is coming close to the one of 1 cm 2 cell efficiencies and total area module performances which are not far away from that value for larger modules.…”

Progress in Upscaling Organic Photovoltaic Devices

“…After these early vacuum-free studies, several others have addressed the upscaling of OPV modules using vacuum-free processing [103,107,147,[165][166][167][168][169][170][171][172][173][174][175][176][177] with strategies used to deposit the top electrodes including spray coating, [165,172] screen-printing, [103,147,166,170,176] rotary screen printing, [169,174] inkjet printing, [166,173] blade-coating, [107,167,175,177] and gravure printing. [168] However, despite all these studies, only a few reported modules displayed PCEs close to or higher than 5.0%.…”

Shining Light on Organic Solar Cells

“…For example, ink-jet printing allows a most flexible change of the shape of the solar cells by simply uploading the required pattern onto the production system. [68] In contrast, vacuum processing would require a change of shadow masks each and every time a customer requires a different solar cell layout. Likewise, the rather low energy consumption of printing and coating processes reflects on the lower energy payback times.…”