# Estimation of the potential efficiency of a multijunction solar cell at a limit balance of photogenerated currents

## Abstract

A method is proposed for estimating the potential efficiency which can be achieved in an initially unbalanced multijunction solar cell by the mutual convergence of photogenerated currents: to extract this current from a relatively narrow band-gap cell and to add it to a relatively wide-gap cell. It is already known that the properties facilitating relative convergence are inherent to such objects as bound excitons, quantum dots, donor-acceptor pairs, and others located in relatively wide-gap cells. In fact, the proposed method is reduced to the problem of obtaining such a required light current-voltage (I–V) characteristic which corresponds to the equality of all photogenerated short-circuit currents. Two methods for obtaining the required light I–V characteristic are used. The first one is selection of the spectral composition of the radiation incident on the multijunction solar cell from an illuminator. The second method is a double shift of the dark I–V characteristic: a current shift J{sub g} (common set photogenerated current) and a voltage shift (−J{sub g}R{sub s}), where R{sub s} is the series resistance. For the light and dark I–V characteristics, a general analytical expression is derived, which considers the effect of so-called luminescence coupling in multijunction solar cells. The experimental I–V characteristicsmore »

- Authors:

- Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)

- Publication Date:

- OSTI Identifier:
- 22469955

- Resource Type:
- Journal Article

- Journal Name:
- Semiconductors

- Additional Journal Information:
- Journal Volume: 49; Journal Issue: 5; Other Information: Copyright (c) 2015 Pleiades Publishing, Ltd.; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1063-7826

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 36 MATERIALS SCIENCE; COMPARATIVE EVALUATIONS; COUPLING; EFFICIENCY; ELECTRIC CONDUCTIVITY; ELECTRIC POTENTIAL; ENERGY GAP; EXCITONS; GALLIUM ARSENIDES; GERMANIUM; INDIUM PHOSPHIDES; LUMINESCENCE; POTENTIALS; QUANTUM DOTS; SEMICONDUCTOR JUNCTIONS; SOLAR CELLS; VISIBLE RADIATION

### Citation Formats

```
Mintairov, M. A., E-mail: mamint@mail.ioffe.ru, Evstropov, V. V., Mintairov, S. A., Shvarts, M. Z., Timoshina, N. Kh., and Kalyuzhnyy, N. A.
```*Estimation of the potential efficiency of a multijunction solar cell at a limit balance of photogenerated currents*. United States: N. p., 2015.
Web. doi:10.1134/S1063782615050164.

```
Mintairov, M. A., E-mail: mamint@mail.ioffe.ru, Evstropov, V. V., Mintairov, S. A., Shvarts, M. Z., Timoshina, N. Kh., & Kalyuzhnyy, N. A.
```*Estimation of the potential efficiency of a multijunction solar cell at a limit balance of photogenerated currents*. United States. doi:10.1134/S1063782615050164.

```
Mintairov, M. A., E-mail: mamint@mail.ioffe.ru, Evstropov, V. V., Mintairov, S. A., Shvarts, M. Z., Timoshina, N. Kh., and Kalyuzhnyy, N. A. Fri .
"Estimation of the potential efficiency of a multijunction solar cell at a limit balance of photogenerated currents". United States. doi:10.1134/S1063782615050164.
```

```
@article{osti_22469955,
```

title = {Estimation of the potential efficiency of a multijunction solar cell at a limit balance of photogenerated currents},

author = {Mintairov, M. A., E-mail: mamint@mail.ioffe.ru and Evstropov, V. V. and Mintairov, S. A. and Shvarts, M. Z. and Timoshina, N. Kh. and Kalyuzhnyy, N. A.},

abstractNote = {A method is proposed for estimating the potential efficiency which can be achieved in an initially unbalanced multijunction solar cell by the mutual convergence of photogenerated currents: to extract this current from a relatively narrow band-gap cell and to add it to a relatively wide-gap cell. It is already known that the properties facilitating relative convergence are inherent to such objects as bound excitons, quantum dots, donor-acceptor pairs, and others located in relatively wide-gap cells. In fact, the proposed method is reduced to the problem of obtaining such a required light current-voltage (I–V) characteristic which corresponds to the equality of all photogenerated short-circuit currents. Two methods for obtaining the required light I–V characteristic are used. The first one is selection of the spectral composition of the radiation incident on the multijunction solar cell from an illuminator. The second method is a double shift of the dark I–V characteristic: a current shift J{sub g} (common set photogenerated current) and a voltage shift (−J{sub g}R{sub s}), where R{sub s} is the series resistance. For the light and dark I–V characteristics, a general analytical expression is derived, which considers the effect of so-called luminescence coupling in multijunction solar cells. The experimental I–V characteristics are compared with the calculated ones for a three-junction InGaP/GaAs/Ge solar cell with R{sub s} = 0.019 Ω cm{sup 2} and a maximum factual efficiency of 36.9%. Its maximum potential efficiency is estimated as 41.2%.},

doi = {10.1134/S1063782615050164},

journal = {Semiconductors},

issn = {1063-7826},

number = 5,

volume = 49,

place = {United States},

year = {2015},

month = {5}

}