Comparing optical performance of a wide range of perovskite/silicon tandem architectures under real-world conditions

Abstract

Since single junction c-Si solar cells are reaching their practical efficiency limit. Perovskite/c-Si tandem solar cells hold the promise of achieving greater than 30% efficiencies. In this regard, optical simulations can deliver guidelines for reducing the parasitic absorption losses and increasing the photocurrent density of the tandem solar cells. In this work, an optical study of 2, 3 and 4 terminal perovskite/c-Si tandem solar cells with c-Si solar bottom cells passivated by high thermal-budget poly-Si, poly-SiOx and poly-SiCx is performed to evaluate their optical performance with respect to the conventional tandem solar cells employing silicon heterojunction bottom cells. The parasitic absorption in these carrier selective passivating contacts has been quantified. It is shown that they enable greater than 20 mA/cm2 matched implied photocurrent density in un-encapsulated 2T tandem architecture along with being compatible with high temperature production processes. For studying the performance of such tandem devices in real-world irradiance conditions and for different locations of the world, the effect of solar spectrum and angle of incidence on their optical performance is studied. Passing from mono-facial to bi-facial tandem solar cells, the photocurrent density in the bottom cell can be increased, requiring again optical optimization. Here, we analyse the effect of albedo, perovskite thickness and band gap as well as geographical location on the optical performance of these bi-facial perovskite/c-Si tandem solar cells. Our optical study shows that bi-facial 2T tandems, that also convert light incident from the rear, require radically thicker perovskite layers to match the additional current from the c-Si bottom cell. For typical perovskite bandgap and albedo values, even doubling the perovskite thickness is not sufficient. In this respect, lower bandgap perovskites are very interesting for application not only in bi-facial 2T tandems but also in related 3T and 4T tandems.

Laminated Monolithic Perovskite/Silicon Tandem Photovoltaics

“…Further potential advancements to improve the J sc would be optimization of the perovskite thickness according to its bandgap energy, which was previously reported increases generated energy yield. [15,21,59,60] In addition, since the current of the laminated tandem devices is slightly limited by the SHJ bottom solar cell (see Figure 1d), the current matching could be further improved by increasing the perovskite bandgap of the top PSC. [14,57] The bandgap of the triple-cation perovskite absorber employed in this work is ≈1.64 eV, as determined from the inflection point of the EQE.…”

Hybrid Organic–Inorganic Perovskite Halide Materials for Photovoltaics towards Their Commercialization

“…In comparison to the PCE values in Table 2, the 2-T configurations of CIGS/Cs 0.05 (MA 0.17 FA 0.83 ) 0.95 Pb(I 0.83 Br 0.17 ) 3 [33,138] are better by 1.08-fold compared to those of the 4-T configurations. The 4-T configurations experience optical loss, which is found in the encapsulation and absorption in the transparent conductive electrode [139], which affects the PCE. The 2-T configurations experience series resistance loss in the large-area modules [140].…”

Polymer Films for Photovoltaic Applications

“…In [138], Caliskan et al synthesized a donor material based on benzo dithiophene by attaching a 2-(2-octyldodecyl)selenophene ring at the fourth and eighth position of benzene ring in BDT. The structure of the solar cell was ITO/PEDOT:PSS/Polymer:PC 71 BM/LiF/Al and the obtained PCEs were 2.36%, 2.07% and 2.45% for P1, P2 and P3, respectively [139]. Guo et al synthesized narrow bandgap (1.6 eV) conjugated polymers based on bis(2-alkyl)-5,8-dibromo-6,7-difluoroquinoxaline-2,3dicarboxylate (EF-Qx) unit.…”