The effect of distributed series resistance on the dark and illuminated current—Voltage characteristics of solar cells

Author

Araújo, Gerardo L. ; Cuevas, Andrés ; Ruiz, Jose M.

Author_Institution

Universidad Politécnica de Madrid, Madrid, Spain

Volume

33

Issue

3

fYear

1986

fDate

3/1/1986 12:00:00 AM

Firstpage

391

Lastpage

401

Abstract

Distributed series resistance effects in solar cells are analyzed and the correctness of representing these by a lumped parameter is discussed for any conditions of bias and illumination. In addition to a general mathematical methodology, analytical expressions are derived to simplify the estimation of series resistance effects on the dark and illuminated $J-V$ characteristics of the cell. The equivalent series resistance (rs) in the dark is found to decrease with current density $J$ from $r_{b} + r_{e}/3$ at small $J$ to ( $r_{e} r_{b})^{1/2}$ at very high $J$ , where reand rbare the emitter layer and base region resistances, respectively. For illuminated conditions rsdepends on $J$ as well, being maximum near short-circuit and minimum near open-circuit; however, rsfurther depends on the photogenerated current JL: its short-circuit value increases with JLfrom $r_{b} + r_{e}/3$ to $r_{b} + r_{e}/2$ and the open-circuit value decreases with JLfrom $r_{b} + r_{e}/3$ to $(r_{e}r_{b})^{1/2}$ . The variability of rsis therefore related to the relative importance of rband $r_{e};r_{b}$ plays the role of attenuating this variability, a situation not well recognized previously. Previous theoretical and experimental work is critically reviewed throughout this paper.

Keywords

Contact resistance; Current density; Current-voltage characteristics; Fabrication; Fingers; Lighting; Mathematical model; Metallization; Photovoltaic cells; Voltage;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/T-ED.1986.22500

Filename

1485717