Loss Analysis in Perovskite Photovoltaic Modules

Abstract

Hybrid metal-halide perovskite-based thin-film photovoltaics (PVs) have the potential to become the next generation of commercialized PV technology with certified power conversion efficiencies reaching 24% on devices having 0.1 cm 2 area. Recent efforts in upscaling this technology result in an efficiency of 12.6% for 354 cm 2 modules. However, upscaling loss for perovskite-based PVs is higher than for any other PV technology. In this study, upscaling losses of devices with aperture area 0.1, 4, and 100 cm 2 are investigated, with a focus on layer inhomogeneities. Electroluminescence, dark lock-in thermography, microphotoluminescence spectroscopy, and electron spectroscopy are used to analyze and group layer inhomogeneities with a minimal size of 10 μm and to compare loss mechanisms for radial and linear deposition techniques. Analysis results help to identify current processing pitfalls, where understanding and control of perovskite crystal formation plays the crucial role.

Perovskite modules with 99% geometrical fill factor using point contact interconnections design

“…The same trend is also visible with fill factor (FF), but not with V OC and J SC . The variation in results of the samples is due to the sample‐to‐sample and batch‐to‐batch variations of spin‐coated solar modules, as discussed in our previous work 5 …”

“…The highest GFF achieved is 95% 9,16 using ps pulsed laser patterning. Hence, the module inactive area loss is 5% or more, making this the second most significant loss mechanism after layer inhomogeneity loss 5 . In this work, we show how an inactive area loss can be decreased from 5% to 1% by optimizing the design of the module to point contact interconnections 17 and processing perovskite modules with 98.5% and 99% GFF.…”

“…Based on latest results, the upscaling loss is decreasing. The small area solar cell to large area solar module upscaling loss consists of four interdependent loss mechanisms: layer inhomogeneity loss, P2 ohmic loss, sheet resistance loss, and inactive area loss 5 . Increase in the knowledge of interface engineering, perovskite crystallization dynamics, and solution engineering adapted to upscalable deposition methods leads to devices with improved layer homogeneity and PCE 5‐10 .…”

“…The small area solar cell to large area solar module upscaling loss consists of four interdependent loss mechanisms: layer inhomogeneity loss, P2 ohmic loss, sheet resistance loss, and inactive area loss 5 . Increase in the knowledge of interface engineering, perovskite crystallization dynamics, and solution engineering adapted to upscalable deposition methods leads to devices with improved layer homogeneity and PCE 5‐10 . Intensified research efforts on the upscaling of perovskite solar modules using other deposition methods, such as evaporation, have yielded improved performances as well 11,12 …”

Stability Assessment of p-i-n Perovskite Photovoltaic Mini-Modules Utilizing Different Top Metal Electrodes

“…With regard to the P3 patterning step, it has been reported that flaking, or the formation of large metal flakes or particles of top metal electrode, causes problems with the electrical isolation of the series interconnected sub-cells in modules [ 20 ]. The flaking causes fluctuations in the maximum power point (MPP) tracking under continuous 1-sun illumination, which result in a reduction in module performance and long-term stability due to intermittent lack of contact with the sub-cells [ 21 ]. To decrease the possibility of flaking of the metal electrode, several strategies have been applied, such as optimization of nanosecond or picosecond laser pulse, and wider P3 scribing with multiple time overlapping [ 16 ].…”