A monolithic three‐terminal GaInAsP/GaInAs tandem solar cell

Steiner, Myles A.; Wanlass, M. W.; Carapella, J. J.; Duda, A.; Ward, Jas S.; Moriarty, T.; Emery, Keith

doi:10.1002/pip.913

Cited by 48 publications

(40 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The correct lower tandem I-V curve is shown in red in Fig. 5, where the upper tandem is biased at Ki PP (or, almost equivalently, at J sc [20]). If the upper tandem is improperly biased at V oc as shown by the green-dashed curve, the lower tandem J sc increases by ~0.6 mA/cm 2 due to the artificially enhanced luminescent coupling.…”

Section: Resultsmentioning

confidence: 99%

“…It is important to set the spectrum correctly for all four junctions so that the appropriate amount of luminescent coupling occurs. Despite the enhanced reflectance from the epoxy, there remains some luminescent coupling from the GaAs junction to the GalnAsP junction, and care must be taken to bias the upper tandem correctly when measuring the lower tandem [20]. The correct lower tandem I-V curve is shown in red in Fig.…”

Section: Resultsmentioning

confidence: 99%

“…Fig. 8 shows the I-V curves and efficiency of a similar concentrator cell under flash illumination, with the upper tandem biased at J sc during the measurement of the lower tandem; as shown in [20], there is little difference between biasing the upper tandem at J sc or V mpp , for well-behaved cells. I-V curves were also measured with the upper tandem biased at V oc to show the effects of luminescent coupling.…”

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

Optically Enhanced Photon Recycling in Mechanically Stacked Multijunction Solar Cells

Steiner

Geisz

Ward

et al. 2016

IEEE J. Photovoltaics

View full text Add to dashboard Cite

Abstract-Multij unction solar cells can be fabricated by mechanically bonding together component cells that are grown separately. Here, we present four-junction four-terminal mechanical stacks composed of GalnP/GaAs tandems grown on GaAs substrates and GalnAsP/GalnAs tandems grown on InP substrates. The component cells were bonded together with a low-index transparent epoxy that acts as an angularly selective reflector to the GaAs bandedge luminescence, while simultaneously transmitting nearly all of the subbandgap light. As determined by electroluminescence measurements and optical modeling, the GaAs subceU demonstrates a higher internal radiative limit and, thus, higher subceU voltage, compared with GaAs subceUs without the epoxy reflector. The best cells demonstrate 38.8 ± 1.0% efficiency under the global spectrum at 1000 W/m 2 and ~ 42% under the direct spectrum at ~100 suns. Eliminating the series resistance is the key challenge for further improving the concentrator cells.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Optically Enhanced Photon Recycling in Mechanically Stacked Multijunction Solar Cells

Steiner

Geisz

Ward

et al. 2016

IEEE J. Photovoltaics

View full text Add to dashboard Cite

show abstract

“…However, without sufficiently detailed spectrum data for calibration, it cannot be determined whether the solar cells performance is slightly lower or higher than designed. For more information about the solar cells, please refer the previous publications by Gray et al [9] and Steiner et al [10].…”

Section: Analysis Of Component Efficienciesmentioning

confidence: 98%

One Lateral Spectrum Splitting Concentrator Photovoltaic architecture: Measurements of current assemblies and analysis of pathways to 40% efficient modules

Wang

Barnett

2010

2010 35th IEEE Photovoltaic Specialists Conference

View full text Add to dashboard Cite

Lateral Spectrum Splitting Concentrator Photovoltaics (LSSCPV) systems are being developed for high energy conversion efficiency. LSSCPV can concentrate available sunlight and laterally split a single beam into bands with different spectra, for absorption by solar cells with matched band gaps. Assemblies of an LSSCPV architecture including four p-n junctions were constructed, and tested by two institutes independently. One of the assemblies demonstrated verified module efficiency of 36.7%. In addition to the whole assembly efficiency, measurement methodology and testing procedure were proposed to assess the performance of each individual component in the system. The comparisons between the expected component efficiencies and the actually measured values, together with the comparisons between the independent assembly efficiency measurements by two organizations helped identify pathways to module efficiency greater than 40%.

show abstract

“…Using calibrated reference cells, the spectrum was adjusted to give the correct photocurrents in each junction, and then the tandems were measured separately. Despite the enhanced reflectance from the epoxy, there remains some luminescent coupling from the GaAs junction to the GalnAsP junction, and care must be taken to bias the upper tandem correctly when measuring the lower tandem [5]. With the upper tandem properly biased at Jsc or Vmp, rather than Voc, the lower tandem Jsc decreases by ~1 mA/cm2, or about 9%.…”

mentioning

confidence: 99%

Mechanically stacked four-junction concentrator solar cells

Steiner

Geisz

Ward

et al. 2015

2015 IEEE 42nd Photovoltaic Specialist Conference (PVSC)

View full text Add to dashboard Cite

-Multijunction solar cells can be fabricated by bonding together component cells that are grown separately. Because the component cells are each grown lattice-matched to suitable substrates, this technique allows alloys of different lattice constants to be combined without the structural defects introduced when using metamorphic buffers. Here we present results on the fabrication and performance of four-junction mechanical stacks composed of GalnP/GaAs and GalnAsP/GalnAs tandems, grown on GaAs and InP substrates, respectively. The two tandems were bonded together with a lowindex, transparent epoxy that acts as an omni-directional reflector to the GaAs bandedge luminescence, while simultaneously transmitting nearly all of the sub-bandgap light. As determined by electroluminescence measurements and optical modeling, the GaAs subcell demonstrates a higher internal radiative limit and thus higher subcell voltage, compared with GaAs subcells without enhanced internal optics; all four subcells exhibit excellent material quality. The device was fabricated with four contact terminals so that each tandem can be operated at its maximum power point, which raises the cumulative efficiency and decreases spectral sensitivity. Efficiencies exceeding 38% at one-sun have been demonstrated. Eliminating the series resistance is the key challenge for the concentrator cells. We will discuss the performance of one-sun and concentrator versions of the device, and compare the results to recently fabricated monolithic four-junction cells.

show abstract

A monolithic three‐terminal GaInAsP/GaInAs tandem solar cell

Cited by 48 publications

References 18 publications

Optically Enhanced Photon Recycling in Mechanically Stacked Multijunction Solar Cells

Optically Enhanced Photon Recycling in Mechanically Stacked Multijunction Solar Cells

One Lateral Spectrum Splitting Concentrator Photovoltaic architecture: Measurements of current assemblies and analysis of pathways to 40% efficient modules

Mechanically stacked four-junction concentrator solar cells

Contact Info

Product

Resources

About