After around 10 years of research, perovskite cells are one of the most promising technologies in the field of photovoltaic. Despite this, there are still hurdles to overcome, such as stability and inhomogeneities in upscale processes, before it can be commercialized. It is therefore necessary to find a protocol to provide a quality assessment of the perovskite cells and identify the type of defects present inside. Electroluminescence (EL) imaging is an ideal candidate to meet these requirements, as it allows defect detection through the application of a voltage/current. We performed electroluminescence characterization on perovskite cells and modules fabricated at IPVF and showing efficiencies between 14 and 18%. We observed unusual behaviors such as transient phenomena, cell extinction or alternating cell luminescence. To better understand these phenomena we modeled our modules using LTSpice. We managed to reproduce these experimental behaviors by varying parameters such as shunt resistance or recombination rate and observing their effect on modeled EL intensity. Moreover, we can also identify which type of defect is predominant according to the applied voltage. Thanks to this work, we determined a precise protocol to link certain electroluminescent behaviors of the module to a specific physical parameter failure and to their potentially related synthesis defect. To go further, we are working on a 2D version of the model that will allow us to a better understanding of the effect of local inhomogeneities inside a larger cell in larger modules.
4-terminal tandem solar cells with an efficiency of 21.7% was synthesized and modelled, combining a semitransparent perovskite solar cell (PSC) as top cell with an efficiency of 16.6% and a commercially-available Aluminium Back Surface Field (Al-BSF) silicon bottom cell. In order to further improve the efficiency of the tandem solar cell, the parasitic optical losses in the PSC have to be minimized, mostly in the near infrared region (NIR), in order to optimize the efficiency of the silicon cell. The modelling of the optical path into the PSC was obtained with the transfer matrix method in order to identify precisely the losses and to optimize the tandem cells. Two interfaces with the air appear critical to decrease parasitic reflection, and the TCO layers and the substrate are mainly responsible for absorption in the NIR. A first optimization allow to improve the efficiency at 23.2% by replace the soda-lime glass, using an anti-reflection coating on the glass-air interface and a interlayer between the silicon and the perovskite cell. A second improvement concerns the two FTO and ITO electrodes, and show that a reduction of their absorption by 10 allow to reach 23.7% (+2%). Finally, the simulated tandem cell reaches 25.5% (+3.8%) when all the improvements are combined. Thus, this work aims to quickly test the interest of various materials, by the prediction of the optical properties of the PSC and their impact on the efficiency of the bottom silicon cell and in consequently the complete tandem cell.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.