Characteristics Of Silicon Solar Cells Research Articles

Investigation of polyvinyl butyral coatings with carbon quantum dots on the characteristics of silicon solar cells

Investigation of polyvinyl butyral coatings with carbon quantum dots on the characteristics of silicon solar cells

Investigation of the changes in the electrical parameters of solar panels with the passage of operation time

After several years of using solar cells, its electrical parameters are degraded. in this paper, to simulate of aging, solar cells were exposed to the different doses of gamma radiation. The (I–V) characteristics of silicon solar cells were studied before and after gamma irradiation. Experimental results showed that the electrical parameter of solar panel such as short circuit current, open circuit voltage, and efficiency decrease with the increase of the gamma doses. As well as, dependence of Voc and Isc according to the absorbed dose for different illumination levels has been investigated.

Contactless measurement of current-voltage characteristics for silicon solar cells

The measurement of the current-voltage (IV) characteristics is the most important step for quality control and optimization of the fabrication process in research and industrial production of crystalline silicon solar cells. We propose a methodology to determine the IV characteristics of silicon solar cells in a contactless way. We summarize the theory behind the method, describe the experimental setup and prove the validity of the concept by comparing contactless with conventionally measured IV results. We demonstrate that the differences in open-circuit voltage, short-circuit current, fill factor, and efficiency are smaller than 2.5 %rel for a test set consisting of four passivated emitter and rear cells (PERC cells), two tunnel oxide passivated contact (TOPCon) cells and a silicon heterojunction (SHJ) cell. The methodology eliminates mechanical stress on the solar cells and the time required for contacting the cells, does not require broad busbars for contacting and, hence, enables to reduce the silver consumption, simplifies the measurements of shingle cells and potentially shortens the required time, avoids shading by the contact units and consumable costs for the probes, and yields additional information (reflectance spectrum, quantum efficiency) on the cells compared to conventional IV testing. The methodology might facilitate further applications in the future, e.g., contactless outdoor testing of modules, individual diagnosis of failed cells within a module, and on-the-fly IV measurements of cells.

Current-voltage characteristics of silicon solar cells: Determination of base doping concentration and hysteresis correction

The measurement of the current-voltage ( IV ) characteristics is the most important step for quality control and optimization of the fabrication process in research and industrial production of silicon solar cells. The occurrence of transient errors and hysteresis effects in IV -measurements can hamper the direct analysis of the IV -data of high-capacitance silicon solar cells. We propose a novel procedure to reconstruct a quasi-steady-state (qss) IV -characteristics from hysteretic measurements by aligning the generalized current density of forward and backward sweeps. In the process, the base doping concentration N B and the cell thickness d are used as optimization parameters and calculated alongside the qss- IV -curve. We summarize the theory behind the method, describe the experimental implementation and verify the applicability of the approach by comparing the extracted doping concentration to multiple alternative methods. For a test set of more than 100 silicon heterojunction solar cells with doping concentrations between 3 and 7∙10 15 cm -3 a RMSD <3.4∙10 14 cm -3 is achieved. Basic parameter extraction from the qss- IV -curve closely match reference values with a RMSD <0.1 % abs in efficiency and fill factor. • Procedure for hysteresis correction proposed and analyzed. • Successful alignment of hysteretic forward and backward IV -curves. • Base doping concentration, resistivity and cell thickness extracted from hysteresis. • Inline capability at high accuracy without additional hardware demonstrated. • Procedure retroactively applicable to existing data to correct transient errors.

Fabrication and characterization of silicon solar cells towards improvement of power efficiency

In recent years, natural energy has been increasingly popular as a source of electricity. Silicon-based solar cell devices are employed to harvest the natural energy, which uses the photovoltaic effect to convert sunlight into an electromotive force. Texturing was usually done on the solar cell surface using a variety of ways to improve solar cell efficiency. In this work, an inductively coupled plasma reactive ion etching (ICP-RIE) texturing approach has been adopted. This research also examines the fabrication of crystalline silicon solar cells with and without texturing and characterizes them to quantify the efficiency improvement. All the characterization is performed inside a clean room to support efficient results.

Light beam induced current mapping to characterize damage characteristics of silicon solar cell irradiated by continuous-wave laser

Light beam induced current mapping to characterize damage characteristics of silicon solar cell irradiated by continuous-wave laser

Исследование двухсторонних кремниевых солнечных элементов и модулей

The first description of the photoelectric effect in a vertical p-n transition in a silicon crystal dates back to 1941. The development of solar photovoltaic energy began in 1954 after the development of a single-sided planar silicon solar cell in the USA, in which the p-n junction is located parallel to the working illuminated surface. (Research purpose) The research purpose is in conducting an analytical review of the designs and electrophysical characteristics of double-sided solar cells and modules, justifying the leading role of Soviet and Russian scientists in its creation and assessing the prospects for the use of double-sided solar cells and modules in solar photovoltaic energy. (Materials and methods) The first double-sided planar solar cells made of silicon were developed in the USSR in 1969-1970 and were widely used for power supply of low-orbit spacecraft; the first double-sided matrix solar cells with a vertical p-n transition made of silicon were created in the USSR in 1967-1970 and were first used at the Venera-7 interplanetary station in 1970. (Results and discussion) As a result of studies of various types of double-sided matrix solar cells, the following limiting characteristics were obtained: voltage density is 100 volts per square centimeter; linear dependence of the current in the illumination range is up to 10 kilowatts per square centimeter; voltage of one module is of 1000 volts; efficiency at illumination of 10 kilowatts per square meter is of 25 percent; efficiency at monochromatic illumination of 950-1060 nanometers is of 36-42 percent; the maximum voltage of the solar battery is of 32 kilovolts. A global solar power system consisting of three solar power plants measuring 200 by 200 kilometers from double-sided solar modules installed in Australia, Africa and Latin America, and connected by an electric transmission line, will provide year-round and round-the-clock energy supply to the Earth in the amount of 26,000 terawatt-hours per year under the program of transition to carbon-free energy. (Conclusions) During the analysis of the design, manufacturing technologies and characteristics of silicon solar cells with one and two working surfaces, it was revealed that double-sided solar cells have the greatest prospects for development in the solar energy industry.

Breakdown of temperature sensitivity of silicon solar cells by simulation input parameters

As the electrical characteristics of silicon solar cells depend significantly on their temperature T of operation, it is vital to analyze and understand the contributions of the various cell properties in detail in order to optimize silicon solar cells for improved energy output in realistic operation conditions. Within a detailed electro-optical solar cell model, as used for numerical device simulation, accounting for full T-dependence of all cell properties has rarely been attempted to date. This is mainly due to the T-dependence of simulation input parameters not being well known or difficult to measure, resulting in unknown inaccuracy for T-dependent device simulations. This study improves previous T-dependent device models by including the T-dependence of injection-dependent bulk lifetime τbulk as well as lumped skin surface recombination parameter J0,skin, which are commonly assumed T-independent, for the “lumped skin” multidimensional device model employed by the software Quokka3. With this improved T-dependent device model, we present a comprehensive breakdown of a typical PERC cell's temperature sensitivity by each simulation input parameter. As figures of merit we simulate T-coefficients of IV-parameters, as well as energy yields. Overall, we find that the relative influence of the T-dependence of τbulk and J0,skin is rather small for our examples, clarifying that for modeling typical PERC cells neglecting of their T-dependence does not result in a substantial error. Nonetheless, T-dependency of the bulk material has been found to vary significantly. Also, there remains substantial uncertainty of actual T-dependence of recombination at contacts and lowly doped surfaces worth of further investigations.

Cogeneration Plants with Solar Radiation Concentrators

Results from experimental studies of a solar cogeneration system with linear photovoltaic modules of a fundamentally new design are presented. The Ʌ-shaped frontal walls are installed face-to-face at an angle to each other and mutually shield their own thermal radiation, which decreases the radiation heat losses by 27% compared with linear photovoltaic modules of the known designs. The photocurrent generated by cooled solar cells is directed to a system for charging chemical batteries and the thermal energy released is transmitted to the unconsumed intermediate heat-transfer fluid and then, through the surface of coil pipes of counter-current heat exchangers, to the consumed process water of the outer circulation circuit. The further transportation of thermal energy to the storage system occurs by natural circulation of the consumed process water through the temperature gradient formed by the control system over the height between the heat source, the heat exchanger, and the heat receiver, an insulated container (a heat accumulator). For the first time, efficient controlled transportation of heat has been implemented without using a circulation pump owing to the excess thermal energy released during the conversion of solar energy by the solar cells and a photo-selective film installed in the focal spot of the optical concentrator. Thus, a possibility of increasing the temperature of the heat-transfer fluids at the cogeneration system outlet has been offered. A two-circuit circulation system allows for separation of unconsumed heat-transfer fluids (antifreezing solutions) and the consumed fluid (the process water) by the pressure in the channels and installation of a linear counter-current heat exchanger that performs the functions of a supporting platform’s mechanical axis along the rotational axis of the optical concentrator. The system uses a dual-axis solar tracking concentrating system comprised of flat mirrors installed at an angle to the horizon. The arrangement of the Ʌ-shaped photovoltaic modules on the supporting framework in series along the heat-transfer-fluid path allows for a reduction in the overall dimensions of the channels, an increase in the total efficiency of the solar cells, and simplification of the encapsulation technology. A method for calculating the output of the cogeneration plant is provided. The method is based on the experimentally measured characteristics of silicon solar cells and heat losses in the channels of the linear photovoltaic modules.

Plasmonic effects of two-dimensional indium-nanoparticles embedded within SiO2 anti-reflective coating on the performance of silicon solar cells

This study experimentally examined the plasmonic near-field and far-field effects of two-dimensional (2-D) indium-nanoparticles (In-NPs) embedded within an anti-reflective SiO2 layer on the optical and electrical characteristics of silicon solar cells. The dimensions and profiles of the 2-D In-NPs were derived from scanning electron microscope images (top-view and side-view) using Image-J software. The surface plasmon resonance of the 2-D In-NPs was estimated from Raman scattering and absorbance measurements. Measurements of optical reflectance and external quantum efficiency revealed that near-field and far-field plasmonic effects depended on the thickness of the spacer and capping layers. The influence of these phenomena on photovoltaic performance was confirmed in terms of photovoltaic current density-voltage under AM 1.5 G illumination. The application of a 90-nm thick SiO2 anti-reflective layer was shown to enhance conversion efficiency by 23.85% (compared to the bare reference cell), and the inclusion of In-NPs between an 18-nm thick spacer layer and 72-nm thick capping layer extended this improvement to 34.16%.

Measurement and Analysis of Optical Characteristics of Silicon Solar Cell Using Integrating Sphere

The aim of this paper is to analyze the optical parameters of solar cell materials using the integrating sphere. The optical parameters including reflectance, transmittance, absorptance and emissivity are measured for the samples ZnO with 0.025 M concentration, ZnO with 0.05 M concentration, ZnO with 0.1 M concentration and Cu/Ti/SiO2 with 0.025 M concentration. The transmittance and reflectance of the samples are calculated with respect to the wavelengths to find whether the samples absorb light of the portion of the solar spectrum. These optical characteristics are measured by using integrating sphere and this work will lead to the analysis of quality of material used for coating the photovoltaic cell in order to increase the conversion efficiency of photovoltaic system.

Influence of the semiconductor/metal rear contact on the performance of n(a-Si:H)/i(a-Si:H)/p(c-Si) heterojunction solar cells

The aim of this work is to analyze on the results of using of Al/Ag layer as a rear contact to improve the performance of heterojunction silicon solar cells. An analytical method is presented to extract the physical parameters of the equivalent circuit. These parameters are extracted to simulate the I(V) characteristic of heterojunction silicon solar cells, with Al and Al/Ag rear-metal contact. A good agreement between our analytical method and experimental measurement of electrical characteristics is obtained which show clearly how the Al/Ag rear contact can improve the characteristics of silicon solar cells. The influence of the rear-metal contact on the performance of the c-Si(p)-based bifacial HIT solar cell, i.e., the ZnO/Al/a-Si:H(n)/a-Si:H(i)/c-Si(p)/metal solar cell, is investigated in detail by computer simulation using the AFORS-HET software. Accordingly, the design optimization of the bifacial HIT solar cells on c-Si(p) substrates is provided. These simulation show an optimal conversion efficiency of 23% when the rear-metal contact is perfectly ohmic.

Innovative experimental setup for thermal and electrical characterization of silicon solar cells under controlled environmental conditions

The optimization of solar cells properties with thermal criteria gives the possibility to achieve higher conversion efficiency in outdoor conditions. An innovative setup that allows the control of the surroundings of a solar cell is described. Under such specific conditions, the cell temperature can be stabilized and measured. The variation of the cell temperature with the applied bias is experimentally observed and quantified. Between short circuit current density (Jsc) and open circuit voltage (Voc), a slight difference of temperature is observed, revealing a variation of the thermal equilibrium between these two points. The resistivity of the absorber and the input power density are found to influence this temperature shift. From the experimental results, it appears that the emissivity of the solar cell increases with the applied voltage due to an increase in the excess carrier concentration. Consequently, the operating temperature at open-circuit is lower than at short-circuit.

Optimal design of an antireflection coating structure for enhancing the energy-conversion efficiency of a silicon nanostructure solar cell.

In this paper, we present our investigation of the optical and electrical characteristics of silicon solar cells using silicon nanowire, silicon nanocone, silicon nanopillar, and silicon nanopillar/silicon nitride structures, which were obtained by the Ag-assisted electroless etching method and ICP etching with extreme ultraviolet lithography. We introduced the formation mechanism for four kinds of solar cells. We simulated the absorption of four structures for different parameters. Furthermore, we also performed current density–voltage (J–V) characterization of the samples with silicon nitride, which exhibited an improvement of the power conversion efficiency (PCE) in contrast to the samples without silicon nitride. It was found that the properties of trapping light for silicon nitride had a prominent impact on the improvement of the PCE in the silicon nanopillar solar cells.

The Use of Solar Cells with a Bifacial Contact Grid under the Conditions of Kazakhstan

The paper reports on the results of simulations of output characteristics of silicon solar cells based on the amorphous silicon–crystalline silicon heterojunction. In addition, the prospect of utilizing high-efficiency bifacial silicon solar modules for various orientational configurations is evaluated. The evaluations are based on the geographical location of the city of Astana (Kazakhstan) located at 51.2° N and 71.4° E at an altitude of 354 m above the sea level

Advanced Local Characterization of Silicon Solar Cells

Solar cells made from multicrystalline silicon material, which still represent the majority of solar cells produced today, are by nature inhomogeneous devices. Their bulk excess carrier lifetime, which decisively influences the short circuit current density, the saturation current density, and the effective bulk diffusion length, may vary from position to position by an order of magnitude or more. Moreover, such cells may contain ohmic shunts and, in particular in the edge regions, positions of significant depletion region recombination current. The classical local characterization method for solar cells is light beam‐induced current (LBIC) mapping. This method does not give direct information on factors influencing the dark current density. A reliable quantitative local characterization of inhomogeneous cells can be performed by combining dark lock‐in thermography (DLIT) with electro‐ and photoluminescence (EL and PL) imaging. In this contribution, the well‐established and the most recent findings on the application of these methods are reviewed and typical application examples are presented. It is shown that luminescence imaging is most appropriate for local series resistance imaging and for qualitatively imaging of all kinds of recombination‐active defects. DLIT, on the other hand, shows a lower spatial resolution, but is most appropriate for imaging local two‐diode parameters like depletion region‐ and bulk saturation current densities, the latter allowing to draw conclusions also to the local short circuit current density. A comprehensive local characterization of silicon solar cells is possible by applying both DLIT and luminescence imaging, which complement each other.

The effect of substrate morphological structure on photoelectrical conversion performance of silicon solar cell

A novel method is proposed to evaluate electrical characteristics of silicon solar cell at real operating conditions. Silicon solar cells with different substrate morphological structures have various photoelectrical performances. The effect of substrate morphological structure on photoelectrical conversation performance of silicon solar cell has been investigated by illustration analysis, mathematical model and I-V test system. Results show that the solar cell with the porous-sponge like substrate has better electrical characteristics than those with conical like substrate morphological structure. The output power of porous substrate solar cell can exceed by 11% at 40 degree incident angle of sunlight compared to conical substrate solar cell.

Influence of nanostructured ITO films on surface recombination processes in silicon solar cells

This paper describes the results of comparative studies of illumination current- voltage characteristics and spectral characteristics of silicon solar cells with rear location of the collector p-n-junction for the cases of non-passivated and passivated front illuminated surface. Passivation was performed by silicon dioxide layer or ITO layer. It was found that ITO layer surface passivation with formation of ITO/silicon heterojunction, unlike silicon dioxide layer passivation, leads to a significant reduction of the effective surface recombination velocity. It significantly increases the value of the internal quantum efficiency in the wavelength range from 550 to 1050 nm and, as a result, significantly increases the value of short-circuit current of solar cells.

Influence of silver nanoparticles on the photovoltaic parameters of silicon solar cells

Influence of Ag nanoparticles on optical and photovoltaic properties of, silicon substrates, silicon solar cells and glass have been investigated. Silver nanoparticles have been fabricated by evaporation of thin Ag layers followed by the thermal annealing. The surface plasmon resonance peak was observed in the absorbance spectrum at 470 nm of glass with deposited silver nanoparticles. It is demonstrated that deposition of silver nanoparticles on silicon substrates was accompanied with a significant decrease in reflectance at the wavelength 360-1100 nm and increase of the absorption at wavelengths close to the band gap for Si substrates. We studied influence of Ag nanoparticles on photovoltaic characteristics of silicon solar cells without and with common use antireflection coating (ARC). It is shown that silver nanoparticles deposited onto the front surface of the solar cells without ARC led to increase in the photocurrent density by 39% comparing to cells without Ag nanoparticles. Contrary to this, solar cells with Ag nanoparticles deposited on front surface with ARC discovered decrease in photocurrent density. The improved performance of investigated cells was attributed to Ag-plasmonic excitations that reduce the reflectance from the silicon surface and ultimately leads to the enhanced light absorption in the cell. This study showed possibility of application of Ag nanoparticles for the improvement of the conversion efficiency of waferbased silicon solar cells instead of usual ARC.

Short-Circuit Current Density Imaging Via PL Image Evaluation Based on Implied Voltage Distribution

Luminescence imaging has found wide application for the characterization of silicon solar cells and wafers over the past decade. One special application is based on a combination of electroluminescence and photoluminescence imaging. Images of a single solar cell at different operating conditions are taken. With suitable methods, it is possible to evaluate the image series and extract spatially resolved solar cell parameters. In the past, methods have been introduced focusing on the extraction of local dark saturation current density and local series resistance. Past methods usually assumed a laterally homogeneous short-circuit current density corresponding to laterally homogeneous external quantum efficiency. In this study, we give a step-by-step description of a newly developed method, which does not rely on the assumption of homogeneous short-circuit current density. The evaluation method instead additionally yields an image of the local short-circuit current density or of the external quantum efficiency. We apply the method to different solar cell types, and we give a detailed comparison to its predecessor the “coupled determination of dark saturation current density and series resistance” method. We compare the short-circuit current density images with images obtained from the “light beam-induced current” technique.