Mitigating Cut Losses in Interdigitated Back Contact Solar Cells

Mitigating Cut Losses in Interdigitated Back Contact Solar Cells

Chen, N. (TU Delft Photovoltaic Materials and Devices; International Solar Energy Research Center (ISC))
Buchholz, Florian (International Solar Energy Research Center (ISC))
Tune, Daniel D. (International Solar Energy Research Center (ISC))
Isabella, O. (TU Delft Photovoltaic Materials and Devices)
Mihailetchi, Valentin D. (International Solar Energy Research Center (ISC))

2022

The edge recombination losses of crystalline silicon solar cells become significant when they are cut into smaller pieces to be assembled into modules. With the interdigitated pattern of doped p and n regions on the rear side, the interdigitated back contact (IBC) solar cells can be cut through different doped regions. In this study, the cutting losses in IBC solar cells are investigated and various cutting scenarios are studied. Through simulations and experimental measurements, it is found that the cut losses can be reduced by cutting through the back surface field rather than through the emitter. The losses under low light intensity are reduced to an even greater extent. When a 23% cell is cut into 1/3 pieces, the efficiency can be increased by 1.2%rel (cut related losses were improved from 2.0rel to 0.8%rel under standard 1-sun testing conditions, compared to cutting through the emitter. Under low light intensity of 0.25 sun, the improvement is around 2.4%rel. The improvement is mainly due to lower FF losses in the I-V characteristics, and this is further confirmed by Suns-Voc and PL measurements. In the pFF analysis, the additional losses due to laser damage are also observed. This strategy of cutting through the BSF region in IBC solar cells can be quickly adopted in mass production without the need for additional processes or equipment and both module power and energy yield can be increased.

Edge recombination
interdigitated back contact (IBC) cell
Laser beam cutting
laser cutting
Lasers
Loss measurement
low-light performance
Measurement by laser beam
Photovoltaic cells
Standards
Surface emitting lasers

http://resolver.tudelft.nl/uuid:34bccfc3-193f-4bba-9162-79a31ef08b7e

https://doi.org/10.1109/JPHOTOV.2022.3208507

2023-03-27

2156-3381

IEEE Journal of Photovoltaics, 12 (6), 1386-1392

Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.

Institutional Repository

journal article

© 2022 N. Chen, Florian Buchholz, Daniel D. Tune, O. Isabella, Valentin D. Mihailetchi