Antonin Faes

• Project Manager at Centre Suisse d'Electronique et de Microtechnique

Reliable and esthetically pleasing lightweight photovoltaic modules for building integration are expected to grow interest in the consumer market, especially for retrofitting older buildings and storehouses that are not structurally designed to withstand additional dead‐weight. The present work reveals the design of a novel module architecture atta...

Ultraviolet-induced degradation (UV-ID) of various PV cell types was analyzed under optical UV filters with different cutoff wavelengths. Cell types studied included interdigitated back contact (IBC), passivated emitter and rear totally diffused (PERT), and heterojunction technology (HJT) based on crystalline Si (c-Si), and metal halide perovskite...

Predicting the energy output of a bifacial photovoltaic (PV) module is usually not as straightforward as for a monofacial module. The problem usually lies in the estimation of the backside irradiance which strongly depends on the mounting conditions, tracking or fixed positioning and variable ground albedo. We developed a new direct-diffuse power r...

Colouring technologies for Building Integrated Photovoltaics - Colouring technologies available for PV façades - Performance and cost perspective of coloured PV - Reliability of coloured PV

Electric vehicles (EVs) currently dominate the sales in the automotive market. A big leap in this market can be made by developing a photovoltaic product that can be integrated to an EV, as it can boost the driving range of the EV while reducing the charging frequency. Such vehicle-integrated photovoltaic (VIPV) products are already successfully de...

Accurate and reproducible color characterization is essential for colored building integrated photovoltaic products, both for manufacturing quality control and assessing long-term color stability. However, existing characterization techniques struggle to accurately determine color when a surface is behind a transparent layer like a solar PV laminat...

In this paper we discuss evaluation results of light-weight PV laminates using sandwich panels based on honeycomb cores and different types of (fibre-reinforced) thermoplastics as sandwich skins. First, we discuss the fabrication and resulting performance of the PV modules, and then the results of reliability testing that has been carried out (ther...

The EU crystalline silicon (c‐Si) PV manufacturing industry has faced strong foreign competition in the last decade. To strive in this competitive environment and differentiate itself from the competition, the EU c‐Si PV manufacturing industry needs to (1) focus on highly performing c‐Si PV technologies, (2) include sustainability by design, and (3...

The 10th edition of the Workshop on Metallization and Interconnection for Crystalline Silicon Solar Cells took place in November 2022, as a live event in Genk Belgium, but also including online participants. Despite various safety measures related to the Covid 19 pandemic, the event reached its goals of networking and of knowledge sharing in these...

In this work we give an overview of the modules monitoring results achieved within the H2020 funded project called HighLite. A dedicated monitoring online platform has been developed for the project to group and treat the data from all partners with homogeneous procedure. Monitoring of advanced prototypes modules developed in the project and based...

Overview of key results achieved in H2020 HighLite project helping to raise the EU PV industries' competitiveness SUMMARY OF THE ABSTRACT The EU crystalline silicon (c-Si) PV manufacturing industry has faced strong foreign competition in the last decade. To strive in this competitive environment and differentiate itself from the competition, the EU...

Aesthetics plays a major role in the development of BIPV products. Several BIPV module manufacturers attempt to mask the reflective metallic interconnects to obtain uniformly colored modules. This is achieved using expensive manufacturing steps, such as colored stripes with manual positioning. Inks could be an alternative to perform this process au...

Inks are used to mask the metallic ribbons in building integrated photovoltaic (BIPV) for improved visual appearance. In this work, we develop a protocol to assess the stability of inks used to mask metallic ribbons for BIPV applications.

This review focuses on monolithic 2‐terminal perovskite‐silicon tandem solar cells and discusses key scientific and technological challenges to address in view of an industrial implementation of this technology. We start by examining the different crystalline silicon (c‐Si) technologies suitable for pairing with perovskites, followed by reviewing r...

The EU crystalline silicon (c-Si) PV manufacturing industry has faced strong foreign competition in the last decade. To strive in this competitive environment, the EU c-Si PV manufacturing industry needs to focus on highly performing c-Si PV technologies and on reducing environmental impact (lower CO2 footprint, improved sustainability, recyclabili...

For the current PV production about 2000 tons of silver are consumed per year, 10% of the entire world annual silver supply. The PV production is expected to grow significantly in the next decades in order to enable the energy transition to 100% renewables. Annual production volumes in the terawatt range are predicted already for 2030 and this may...

Self-assembled monolayers (SAMs) are widely used to engineer the surface properties of metals and metal oxide layers. This article reports the fabrication of gemini perfluorinated phosphonic acids SAMs on indium tin oxide (ITO). The self-assembled monolayers are to be used for patterning nickel lines by electroplating on ITO in order to obtain low-...

Providing state‐of‐the‐art surface passivation and the required carrier selectivity for both contacts, hydrogenated amorphous silicon thin films are the key components of silicon heterojunction (SHJ) solar cells. After intensive optimization of these layers for standard front and back contacted (FBC) n‐type cells, high surface passivation levels we...

We present a novel, simple and cost-effective method for patterning transparent conductive oxides (TCO) in order to form solar cell's metal grid by electro-plating. Self-assembled monolayers (SAMs) are prepared by dipping substrates in or spraying TCO with perfluorinated and alkylated phosphonic acid solutions. The investigated chemistry and explor...

Soiling is the major cause of power loss of photovoltaics (PV) and concentrated solar power (CSP) in desert areas. Electrodynamic cleaning system (EDS) is an automatic and water‐free integrated cleaning system for mirrors or solar panels, which uses pulsed electric fields to remove dust off their surface. The first EDS field test over a long period...

Planar micro-tracking concentrator photovoltaic modules hold great promises, as they enable the combination of efficiencies greater than 30% with the form factor of conventional rooftop panels operating at fixed tilt. Over the past three years, Insolight has been developing a fixed-tilt system, combining a biconvex silicone lens array, high efficie...

Sodium hypochlorite (NaClO) is a chemical commodity widely employed as a disinfection agent in water treatment applications. Its production commonly follows electrochemical routes in an undivided reactor. Powering the process with photovoltaic (PV) electricity holds the potential to install stand-alone, independent generators and reduce the NaClO p...

Tandem photovoltaic devices based on perovskite and crystalline silicon (PK/c-Si) absorbers have the potential to push commercial silicon single junction devices beyond their current efficiency limit. However, their scale-up to in-dustrially relevant sizes is largely limited by current fabrication methods which rely on evaporated metallization of t...

Failures in the metallic interconnections are among the main degradation modes for photovoltaic modules. Fatigue accumulation due to thermomechanical stresses can result in deterioration of the solder joints or in broken ribbons. In this paper, we first quantify experimentally how the module performance is affected when one or more cell interconnec...

Silicon heterojunction (SHJ) solar cells demonstrate a high conversion efficiency, reaching up to 25.1% using a simple and lean process flow for both-sides-contacted devices, and achieving a record silicon solar cell efficiency of 26.7% in back-contacted configuration. In addition, the field advantages of SHJ cell technology are a native bifacialit...

Over one billion people currently lack access to safe potable water. Those communities, often isolated or settled in remote locations, are thus constantly exposed to a severe health threat due to waterborne pathogens (e.g. cholera, typhus, etc.). It is therefore evident that unavailability of drinking water directly hampers hygiene, education and u...

• From 5-BB to SWCT: • +2.5% power increase (+8Wp)􀍺Silver consumption reduced by 80% • New-generation SWCT is indium-free and UV-transparent: • Indium-free SWCT is certified, with <3% degradation after 1500PTC • UV-transparent SWCT shows gain up to 2% and is certified according to IEC 61215:2016 and IEC 61730:2016. • GG 60-cell: 330Wp (white BS) an...

This paper reports on the development of an innovative back-contacted crystalline silicon solar cell with passivating contacts featuring an interband tunnel junction at its electron-collecting contacts. In this novel architecture, named "tunnel-IBC", both the hole collector patterning and its alignment to the electron collector are eliminated, thus...

This paper reviews recent progress made at CSEM on the development of low-temperature processes for the fabrication of amorphous silicon-based passivated contacts and for the metallization of high-efficiency silicon heterojunction (SHJ) solar cells. Intrinsic a-Si:H passivation layers were optimized by trying to minimize the drop in lifetime usuall...

We successfully demonstrated and reported the highest solar-to-hydrogen efficiency with crystalline silicon cells and Earth-abundant electrocatalysts under unconcentrated solar radiation. The combination of hetero-junction silicon cells and a 3D printed Platinum/Iridium-Oxide electrolyzer has been proven to work continuously for more than 24 hours...

The implementation of practical solar-fuel technologies can trigger a significant increase in the use of renewables in our energy ecosystem. These technologies can directly capture and store solar energy in the form of energy rich molecules, which could be used at a later stage as fuels for transportation or electricity generation. Storing solar-en...

Affordable, stable and earth-abundant photo-electrochemical materials are indispensable for the large-scale implementation of sunlight-driven hydrogen production. Here we present an intrinsically stable and scalable solar water splitting device that is fully based on earth-abundant materials, with a solar-to-hydrogen conversion efficiency of 14.2%....

Combining a Si solar cell with a high-bandgap top cell reduces the thermalization losses in the short wavelength and enables theoretical 1-sun efficiencies far over 30%. We have investigated the fabrication and optimization of Si-based tandem solar cells with 1.8-eV rear-heterojunction GaInP top cells. The III–V and Si heterojunction subcells were...

Silicon heterojunction solar cells demonstrate key advantages of high conversion efficiency, maximum field performance and simplicity of processing. The dedicated materials, processes and technologies used for the metallization and interconnection of this type of cell are reviewed in this paper.

The silicon heterojunction (SHJ) technology has already proven its ability to produce high-efficiency devices, and very competitive production costsat the mass production level can be potentially reached by integrating latest developments. In this work, several of such technology developments are presented related to the PECVD and metallization ste...

In the last few years PV technology has seen continuous improvements, with significant enhancements at the cell and module levels. In addition to the requirement of high efficiency, the long-term reliability of PV modules leads to proposals for innovative module concepts and designs. Meyer Burger has developed a low-temperature wire-bonding technol...

Glass-to-Glass (GG) encapsulation scheme and low temperature cell metallization-interconnection technologies known as Smart Wire Connection Technology (SWCT) are promising alternatives to standard design for highly efficient, long lasting photovoltaic modules. The focus of this work was to study the compatibility of different types of encapsulants...

Copper electroplating is investigated and compared with common silver printing techniques for the front metallization of silicon heterojunction solar cells. We achieve smaller feature sizes by electroplating, significantly reducing optical shadowing losses and improving cell efficiency by 0.4% absolute. A detailed investigation of series resistance...

Silicon heterojunction solar cell technology (HJT) takes advantage of ultra-thin amorphous silicon layers deposited on both sides of monocrystalline silicon wafers, enabling excellent silicon wafer surface passivation resulting in high device power output and in addition to efficient use of thin wafers. A full cell processing platform was developed...

The need to increase the efficiency (Eff) and to reduce the costs of solar cells has led to the new concept of busbarless metallization on the front and the rear sides of cells. However, this technology implies significant challenges, in particular the electrical contacting on the cell for the current-voltage (IV) measurement. This paper will prese...

During the recent year, it has been proven that silicon heterojunction (Si-HJT) solar cells can achieve efficiencies close to 25 % using simple cell structure. However, most of these record cells have been achieved at the R&D scale and only few companies are producing Si-HJT cells and modules on a mass production scale. In light of this observation...

Powder Injection Molding (PIM) gives the possibility to produce, at an industrial rate, ceramic parts with fine details. It is thus a possible approach to reduce the fabrication costs of Solid Oxide Fuel Cells (SOFCs). This work presents fabrication and electrochemical characterization results of injection-molded structured anode-supported SOFCs.Pl...

Solid oxide fuel cells are able to convert fuels, including hydrocarbons, to electricity with an unbeatable efficiency even for small systems. One of the main limitations for long-term utilization is the reduction-oxidation cycling (RedOx cycles) of the nickel-based anodes. This paper will review the effects and parameters influencing RedOx cycles...

Microstructural evolution in solid oxide fuel cell (SOFC) cermet anodes has been investigated using X-ray nanotomography along with differential absorption imaging. SOFC anode supports composed of Ni and yttria-stabilized zirconia (YSZ) were subjected to extended operation and selected regions were imaged using a transmission X-ray microscope. X-ra...

During operation solid oxide fuel cells are stressed by temperature gradients and various internal and external mechanical loads, which must be withstood. This work deals with the optimization of the strength of as-sintered anode supported half-cells by imposing changes to production parameters, such as powder milling and sintering temperature. The...

The mechanical failure of one cell is sufficient to lead to the end of service of a solid oxide fuel cell (SOFC) stack. Therefore, there is growing interest in gaining knowledge on the mechanical properties of the cell materials for stress analysis. This study compiles available data from the literature on the mechanical properties of the most comm...

One of the major limitations of the nickel (Ni) – yttria-stabilized zirconia (YSZ) anode support for solid oxide fuel cells (SOFC) is its low capability to withstand transients between reducing and oxidizing atmospheres (“RedOx” cycle), owing to the Ni-to-NiO volume expansion. This work presents results on different anode supports fabricated by tap...

Nickel oxide and yttria doped zirconia composite strength is crucial for anode-supported solid oxide fuel cells, especially during transient operation, but also for the initial stacking process, where cell curvature after sintering can cause problems. This work first compares tensile and ball-on-ring strength measurements of as-sintered anodes supp...

The main drawback of Ni/YSZ anode supports for solid oxide fuel cell application is their low tolerance to reducing and oxidizing (RedOx) atmosphere changes, owing to the Ni/NiO volume variation. This work describes a structured approach based on design of experiments for optimizing the microstructure for RedOx stability enhancement. A full factori...

Cell durability is a crucial technological issue for SOFC commercialization, and considerable progress has been made in recent years. A number of degradation pathways have been established, amongst which microstructural changes, poisoning effects and formation of less conductive phases. In this study, transmission electron microscopy was used to ob...

Ni-YSZ anode supports were used to fabricate test cells composed of yttria-stabilised zirconia (YSZ) electrolyte and lanthanum strontium ferrite (LSF) or lanthanum strontium manganite (LSM) / YSZ cathodes. These cells were operated at 720 degrees C at an average current density of 0.28 to 0.46 A/cm(2). A central piece of selected anode support was...

State-of-the-art nickel-based SOFC anode-supported cells are highly sensitive to reoxidation of the metal phase at the temperature of utilization. This work presents results on redox stable nickel–YSZ (yttria- stabilized zirconia) anode-supported cells, for both smaller and larger scale cells. A 55cm2 cell was mounted in a SOFC stack repeat element...

Solid Oxide Fuel Cells (SOFC) are a promising technology for high efficiency energy conversion. Powder injection moulding (PIM) is a possible approach to reduce the fabrication costs of SOFC. Components in the form of bars and disks with an intricate pattern of small details have been produced by injection moulding of nickel oxide (NiO) and yttria-...

The weakness of nickel-based solid oxide fuel cell anodes is their low ability to withstand re-oxidation at working temperature, especially for the anode-supported cell design. The volume expansion coming along with nickel (Ni) oxidation induces stresses in the layers and cracks especially for the thin supported electrolyte. Standard Ni-yttria stab...

One of the main drawbacks of anode-supported solid oxide fuel cell technology is the limited capability to withstand reduction and oxidation (“RedOx”) of the Ni phase. This study compares the effect of RedOx cycles on curvature and strength of half-cells, composed of a Ni-YSZ support, a Ni- YSZ anode and an 8YSZ electrolyte. Five different treatmen...

A CFD model was developed to predict with accuracy the local electrochemical performance in an operating solid oxide fuel cell. A particular focus was given on the study of performance limitations and degradation sources caused by the design of the fuel cell, by the choice of materials and components, or by improper operating points. The model is u...

Environmental transmission electron microscopy is used in combination with density functional theory calculations to study the redox stability of a nickel/yttria-stabilized zirconia solid oxide fuel cell anode. The results reveal that the transfer of oxygen from NiO to yttria-stabilized zirconia triggers the reduction reaction. During Ni reoxidatio...

Microstructural evolution of anode supported solid oxide fuel cells (SOFC) during medium-term stack testing has been characterized by scanning electron microscopy (SEM). Low acceleration voltage SEM imaging is used to separate the three anode phases (nickel, yttria-stabilized zirconia and porosity). Microstructural quantification is obtained using...

Microstructural evolution of anode supported solid oxide fuel cells (SOFC) during medium-term stack testing has been characterised by scanning electron microscopy (SEM). Low acceleration voltage SEM imaging is used to separate the three anode phases (nickel, yttria-stabilised zirconia and porosity). Microstructural quantification is obtained using...

We investigated the use of in situ implant formation that incorporates superparamagnetic iron oxide nanoparticles (SPIONs) as a form of minimally invasive treatment of cancer lesions by magnetically induced local hyperthermia. We developed injectable formulations that form gels entrapping magnetic particles into a tumor. We used SPIONs embedded in...

Performance degradation data obtained from single solid oxide fuel cells, tested at 850 °C with air and humidified H2 and using Ni-YSZ anode supported cells, are presented here. Microscopic investigation is carried out on both anode and cathode to quantify variations in the morphology at different operation times. The comparison between the measure...

Environmental transmission electron microscopy was used to characterize in situ the reduction and oxidation of nickel from a Ni/YSZ solid oxide fuel cell anode support between 300-500°C. The reduction is done under low hydrogen pressure. The reduction initiates at the NiO/YSZ interface, then moves to the center of the NiO grain. At higher temperatu...

The common technology for solid oxide fuel cells (SOFC) is based on a cermet (ceramic-metal composite) anode of nickel with yttria stabilized zirconia (YSZ), often used as the supporting structure. One of the main limitations of this technology is the tolerance of the anode towards reduction and oxidation (“RedOx”) cycles. In this study, two techni...

Environmental transmission electron microscopy was used to characterize in situ the reduction and oxidation of nickel from a Ni/YSZ solid oxide fuel cell anode support between 300-500°C. The reduction is done under low hydrogen pressure. The reduction initiates at the NiO/YSZ interface, then moves to the center of the NiO grain. At higher temperatu...

One of the main drawbacks of anode-supported solid oxide fuel cell technology is the limited capability to withstand reduction and oxidation ("RedOx") of the Ni phase. This study compares the effect of RedOx cycles on curvature and strength of half-cells, composed of a Ni-YSZ support, a Ni-YSZ anode and an 8YSZ electrolyte. Five different treatment...

The common technology for solid oxide fuel cells (SOFC) is based on a cermet anode of nickel with yttrium stabilized zirconia (YSZ), often used as the supporting structure. One of the main limitations of this anode technology is the redox tolerance. In this study, two techniques are used to quantify the anode expansion after one redox cycle at diff...

Performance degradation data obtained on single solid oxide fuel cells tested at 850°C with air and humidified H2 and using Ni-YSZ anode supported cells are presented. Microscopic investigation is carried out on both anode and cathode to quantify variations in morphology at different operation times. The comparison between the measurements on the c...

Sample preparation and scanning electron microscopy imaging methods were developed to characterize solid-oxide fuel cell anodes made out of a nickel–yttria-stabilized zirconia porous cermet. The sample preparation uses only tripod polishing and does not require any resin impregnation. To overcome surface damages induced by polishing, as well as to...

As the performances of Solid Oxide Fuel Cells (SOFC) get attractive, long term degradation becomes the main issue for this technology. Therefore it is essential to localise the origin of degradation and to understand its processes in order to find solutions and improve SOFC durability.

Cyanine dyes with absorption edges of almost 1000 nm were used in combination with MEH-PPV for the fabrication of organic solar cells. For blended thin films, a pronounced phase separation between the two components occurred and resulted in photocurrents with different signs for bilayer and bulk heterojunction devices. Absorption spectra and select...

We investigated cyanine heterojunction photovoltaic devices using carbocyanine dyes as donors and buckminsterfullerene (C60) as acceptor. In particular, we focused on the influence of cyanine counterions on the photovoltaic device characteristics. It was found that counterions can be displaced in the applied electric field and give rise to importan...