Demonstration of GaInP2/Si Voltage Matched Tandem Solar Cells

David Bobela, Kirstin Alberi, Kenneth Schmieder, Matthew Lumb, James Moore, Robert Walters, Eric Armour, Leo Matthew, Rajesh Rao, Angelo Mascarenhas

Research output: Contribution to conferencePaper

2 Scopus Citations


Mechanically-stacked tandem solar cells combining existing photovoltaic technologies present a straightforward path toward higher conversion efficiencies. Voltage-matched configurations have been proposed as a simplified approach for fabricating two terminal modules, but they are subject to performance losses compared to four terminal configurations if voltage-matching conditions are not met. Here, we demonstrate a two terminal voltage-matched GaInP 2 /Si tandem with 23% efficiency. Through a combination of experimental measurement and simulation, we explore the impact of voltage and fill factor mismatches between the top and bottom sub-cell strings. Our results show that efficiency losses are minimized when voltage-mismatches are accommodated by designing the bottom strings to have a higher voltage. Fill factor mismatches due to differences in series resistance also lead to changes in the optimal ratio of the number of cells in the top and bottom sub-cell strings.
Original languageAmerican English
Number of pages5
StatePublished - 2018
Event2017 IEEE 44th Photovoltaic Specialist Conference (PVSC) - Washington, D.C.
Duration: 25 Jun 201730 Jun 2017


Conference2017 IEEE 44th Photovoltaic Specialist Conference (PVSC)
CityWashington, D.C.

NREL Publication Number

  • NREL/CP-5K00-67836


  • GalnP2
  • mechanical stack
  • photovoltaic cells
  • silicon
  • voltage matching


Dive into the research topics of 'Demonstration of GaInP2/Si Voltage Matched Tandem Solar Cells'. Together they form a unique fingerprint.

Cite this