TY - JOUR

T1 - Maximizing tandem solar cell power extraction using a three-terminal design

AU - Warren, Emily L.

AU - Deceglie, Michael G.

AU - Rienäcker, Michael

AU - Peibst, Robby

AU - Tamboli, Adele C.

AU - Stradins, Paul

N1 - Publisher Copyright: © 2018 The Royal Society of Chemistry. Copyright: Copyright 2019 Elsevier B.V., All rights reserved.

PY - 2018

Y1 - 2018

N2 - Tandem or multijunction solar cells can greatly increase the efficiency of solar energy conversion by absorbing different energies of the incident solar illumination in semiconductors with different band-gaps, which can operate more efficiently than a single absorber. Many different designs of tandem cells based on high efficiency top cells and Si bottom cells have been proposed, and there is ongoing debate as to whether the sub-cells should be wired in series (to create a tandem device with two terminals) or operated independently (four terminals). An alternative cell configuration that combines some of the strengths of both is a three-terminal device consisting of a top cell optically in series with a modified interdigitated back contact (IBC) Si cell featuring a conductive top contact. Such a configuration can enable improved energy yield while only requiring external wiring on the front and back of the solar cell stack. In this paper, we investigate the operation of three terminal tandems in detail using technology computer aided design (TCAD) device physics simulations. Using III-V top cells as an example case, we show how the addition of a third terminal can deliver comparable power output to a four terminal device, and substantially more power than a two-terminal device, while also enabling power injection and extraction between the two sub-circuits under a variety of spectral conditions.

AB - Tandem or multijunction solar cells can greatly increase the efficiency of solar energy conversion by absorbing different energies of the incident solar illumination in semiconductors with different band-gaps, which can operate more efficiently than a single absorber. Many different designs of tandem cells based on high efficiency top cells and Si bottom cells have been proposed, and there is ongoing debate as to whether the sub-cells should be wired in series (to create a tandem device with two terminals) or operated independently (four terminals). An alternative cell configuration that combines some of the strengths of both is a three-terminal device consisting of a top cell optically in series with a modified interdigitated back contact (IBC) Si cell featuring a conductive top contact. Such a configuration can enable improved energy yield while only requiring external wiring on the front and back of the solar cell stack. In this paper, we investigate the operation of three terminal tandems in detail using technology computer aided design (TCAD) device physics simulations. Using III-V top cells as an example case, we show how the addition of a third terminal can deliver comparable power output to a four terminal device, and substantially more power than a two-terminal device, while also enabling power injection and extraction between the two sub-circuits under a variety of spectral conditions.

UR - http://www.scopus.com/inward/record.url?scp=85051109031&partnerID=8YFLogxK

U2 - 10.1039/c8se00133b

DO - 10.1039/c8se00133b

M3 - Article

AN - SCOPUS:85051109031

VL - 2

SP - 1141

EP - 1147

JO - Sustainable Energy and Fuels

JF - Sustainable Energy and Fuels

IS - 6

ER -