Triple junction solar cells

J. Yang, A. Banerjee, K. Lord, S. Guha, Correlation of component cells with high efficiency amorphous silicon alloy triple junction solar cells and modules. Office for Offidal Publications of the European Communities, Luxembourg, Proceedings of the 2nd World Conference on Photovoltaic Solar Energy Conversion, Vienna, July 6-10, 1998,... 

Table II. Calculated increase in efficiency for a Si triple junction solar cell.

Fig. 7.22 Device structure of a high efficiency GaInP2/GaAs/Ge triple-junction solar cell developed at NREL and commercialized by Spectrolab...

Outer, W., et al. Current-matched triple-junction solar cell reaching 41.1% conversion efficiency under concentrated sunlight. Appl. Phys. Lett. 94, 223504 (2009)... 

In further developments of all-solid-state cells using phthalocyanines as a donor in a mixed layer with an acceptor, PcCu was very successfully used as donor with Ceo as acceptor. Efficiencies of up to 5.7 % were reached in a tandem cell approach using such mixed layers [224]. The approach has been developed further to 12 % efficient cells claimed by the company Heliatek without, however, mentioning specific composition of the cells [225], and 11.1 % efficiency reported for a triple-junction solar cell of the same type using two layers of tetraphenyldibenzoperiflanthene... 

Yusoff ARBM, Kim D, Kim HP, Shneider FK, da Silva WJ, Jang J (2015) A high efficiency solution processed polymer inverted triple-junction solar cell exhibiting a power conversion efficiency of 11.83 %. Energy Environ Sci 8 303-316... 

Polymer multi-junction cells have also achieved noticeable attention. In Table 11.2 we provide an overview of the multi-junction cells that had been published up to the end of 2014. In 2007, Gilot et al showed that it is possible fully to solution process three photoactive layers and two recombination layers based on ZnO/PEDO PSS and obtain a working triple junction solar cell with koc = 2. 19 By the same procedure, six-fold junction cells with... 

Figure 11.16 (a) Device configuration of triple-junction solar cell, (b) Optical constants of the photoactive layers, (c) Energy levels of the materials used. Reproduced from ref. 95 with permission from Wiley. 

These advanees in triple-junction polymer solar cells show the potential for this type of device. Considering that in these triple junctions the photon energy loss ( loss) in each suhcell is at least 0.7 eV, and sometimes even above 1.0 eV (Table 11.2), it can be expected that by developing new materials in which is more tailored to 0.6 eV it will be possible to increase the efficiency of triple-junction solar cells considerably. In our view efficiencies in the 15-20% range are within reach. 

The conversion efficiency of InGaP/GaAs-based multijunction solar cells has been improved in the same way. A schematic illustration of the InGaP/(In)GaAs/Ge triple-junction solar cell reported by Takamoto et al. is shown in Figure 3.14. The device pictured gave an efficiency of 31.5% under standard conditions. ... 

Figure 11.16 (a) Device configuration of triple-junction solar cell, (b) Optical con-... 

Figure 8.17 A schematic diagram showing how a triple junction solar cell might collect current from photons in different parts of the solar spectrum. Light enters the device from the left through the wide-gap solar eell and portions of the spectrum penetrate into the underlying deviees.

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