TY - JOUR

T1 - Three-terminal III-V/Si tandem solar cells enabled by a transparent conductive adhesive

AU - Schnabel, Manuel

AU - Schulte-Huxel, Henning

AU - Rienäcker, Michael

AU - Warren, Emily L.

AU - Ndione, Paul F.

AU - Nemeth, Bill

AU - Klein, Talysa R.

AU - Van Hest, Maikel F.A.M.

AU - Geisz, John F.

AU - Peibst, Robby

AU - Stradins, Paul

AU - Tamboli, Adele C.

N1 - Funding Information: NREL authors acknowledge the support of Waldo Olavarria and Michelle Young for sample growth and processing (devices MP901, MQ339), Al Hicks for graphics support, Byungsul Min for providing refractive index data, Taylor Moot for transmission measurements, and Tom Moriarty for EQE and cell area measurements. The ISFH authors wish to thank Heike Kohlen-berg, Guido Glowatzki and the processing team at ISFH for processing solar cells, and Robert Witteck for support with LTSpice simulations. This work was supported by the Alliance for Sustainable Energy, LLC, the manager and operator of the National Renewable Energy Laboratory for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. Funding was provided by the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Solar Energy Technologies Office under contract number DE-EE00030299. Funding for the work at ISFH was provided by the German Federal Ministry for Economic Affairs and Energy, under grant number 324040 (EASi), and by the European Union's Seventh Framework Programme for research, technological development and demonstration within the “HERCULES” project (grant agreement No. 608498). H. Schulte-Huxel acknowledges support for the Research Fellowship by Deutsche Forschungsgemeinscha (DFG) (grant agreement No. SCHU 3206/1-1). The views expressed in the article do not necessarily represent the views of the DOE or the U.S. Government. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this work, or allow others to do so, for U.S. Government purposes. Publisher Copyright: This journal is © The Royal Society of Chemistry. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.

PY - 2020/11/4

Y1 - 2020/11/4

N2 - Tandem or multijunction solar cells are able to convert sunlight to electricity with greater efficiency than single junction solar cells by splitting the solar spectrum across sub-cells with different bandgaps. With the efficiencies of many common single-junction solar cell materials leveling off near their theoretical efficiency limits, there is renewed interest in applying this approach. However, there is ongoing debate as to the best approach for interconnecting sub-cells in series, or whether it is preferable to operate them independently. In this paper, we provide the first experimental demonstration of a tandem cell architecture with three terminals: one on top of the tandem cell, and two beneath it, in interdigitated back contact configuration. The two cells are interconnected with a transparent conductive adhesive, which is compatible with rough surfaces and exhibits negligible series resistance. Combining GaInP and Si sub-cells in this manner allows us to achieve a GaInP/Si tandem cell with a two-terminal efficiency of 26.4 ± 1.0%. We then show that utilizing all three terminals results in an efficiency boost of 0.9 ± 0.2%, to an efficiency of 27.3 ± 1.0%, and discuss the operation of the cell and its two interacting circuits.

AB - Tandem or multijunction solar cells are able to convert sunlight to electricity with greater efficiency than single junction solar cells by splitting the solar spectrum across sub-cells with different bandgaps. With the efficiencies of many common single-junction solar cell materials leveling off near their theoretical efficiency limits, there is renewed interest in applying this approach. However, there is ongoing debate as to the best approach for interconnecting sub-cells in series, or whether it is preferable to operate them independently. In this paper, we provide the first experimental demonstration of a tandem cell architecture with three terminals: one on top of the tandem cell, and two beneath it, in interdigitated back contact configuration. The two cells are interconnected with a transparent conductive adhesive, which is compatible with rough surfaces and exhibits negligible series resistance. Combining GaInP and Si sub-cells in this manner allows us to achieve a GaInP/Si tandem cell with a two-terminal efficiency of 26.4 ± 1.0%. We then show that utilizing all three terminals results in an efficiency boost of 0.9 ± 0.2%, to an efficiency of 27.3 ± 1.0%, and discuss the operation of the cell and its two interacting circuits.

UR - http://www.scopus.com/inward/record.url?scp=85079178979&partnerID=8YFLogxK

U2 - 10.1039/c9se00893d

DO - 10.1039/c9se00893d

M3 - Article

AN - SCOPUS:85079178979

VL - 4

SP - 549

EP - 558

JO - Sustainable Energy and Fuels

JF - Sustainable Energy and Fuels

IS - 2

ER -