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Here we present the cascade converter (CC), which provides real-time imaging of ionizing radiation (IoR) distribution. It was designed and manufactured with the simplest architecture, utilizing liquid crystal display (LCD) technology. Based on two merged substrates with transparent electrodes, armed with functional layers, with the cell filled with nematic liquid crystal, a display-like, IoR-stimulated CC was achieved. The CC comprises low-absorbing polymer substrates (made of polyethylene terephthalate—PET) armed with a transparent ITO electrode covered with a thin semipermeable membrane of polymer (biphenylperfluorocyclobutyl: BP-PFCB) doped with functional nanoparticles (NPs) of Lu2O3:Eu. This stack was covered with a photoconductive layer of α-Se and finally with a thin polyimide (PI) layer for liquid crystal alignment. The opposite substrate was made of LCD-type glass with ITO and polyimide aligning layers. Both substrates form a cell with a twisted structure of nematic liquid crystal (TN) driven with an effective electric field E e f f . An effective electric field driving TN structure is generated with a sum of (1) a bias voltage V B I A S applied to ITO transparent electrodes and (2) the photogenerated additional voltage V X r a y induced between ITO and α-Se layers with a NPs-doped BP-PFCB polymer layer in-between. The IoR (here, X-ray) conversion into real imaging of the IoR distribution was achieved in the following stages: (1) conversion of IoR distribution into non-ionizing red light emitted with functional NPs, (2) transformation of red light into an electric charge distributed in a layer of the photoconductive α-Se, which is what results in the generation of distributed voltage V X r a y , and (3) a voltage-mediated, distributed switching of the TN structure observed with the naked eye. The presented imaging device is characterized by a simple structure and a simple manufacturing process, with the potential for use as a portable element of IoR detection and as a dosimeter. [ABSTRACT FROM AUTHOR]

This paper proposes molecular and supramolecular concepts for potential application in perovskite solar cells. New air-stable symmetrical imine, with thiadiazole moieties PPL2: (5E,6E)-N2,N5-bis(4-(diphenylamino)benzylidene)-1,3,4-thiadiazole-2,5-diamine), as a hole-transporting material was synthesised in a single-step reaction, starting with commercially available and relatively inexpensive reagents, resulting in a reduction in the cost of the final product compared to Spiro-OMeTAD. Moreover, camphorsulfonic acid (CSA) in both enantiomeric forms was used to change the HOMO-LUMO levels and electric properties of the investigated imine-forming complexes. Electric, optical, thermal, and structural studies of the imine and its complexes with CSA were carried out to characterise the new material. Imine and imine/CSA complexes were also characterised in depth by the proton Nuclear Magnetic Resonance 1H NMR method. The position of nitrogen in the thidiazole ring influences the basicity of donor centres, which results in protonation in the imine bond. Simple devices of ITO/imine (with or without CSA(−) or CSA(+))/Ag/ITO architecture were constructed, and a thermographic camera was used to find the defects in the created devices. Electric behaviour was also studied to demonstrate conductivity properties under the forward current. Finally, the electrical properties of imine and its protonated form with CSA were compared with Spiro-OMeTAD. In general, the analysis of thermal images showed a very similar response of the samples to the applied potential in terms of the homogeneity of the formed organic layer. The TGA analysis showed that the investigated imine exhibits good thermal stability in air and argon atmospheres. [ABSTRACT FROM AUTHOR]

Due to its high electron affinity and electron mobility in a wide absorption range of the visible solar spectrum, [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) is often used as an efficient acceptor in organic photovoltaics. In turn, imines are additives to the active layer of organic solar cells, mainly due to the free electron pair of the imine nitrogen atom and the presence of various chemical groups affecting the polarity and conformations of molecules. However, the attainable efficiency is not as high as expected. Therefore, we have systematically investigated two imines and their mixtures with PC71BM by spectroscopic (the high pressure UV–Vis and frequency domain dielectric), thermoelectric, and mechanical methods for organic, flexible photovoltaics. Both the imines, (N,NʹE,N,NʹE)-N,Nʹ-([2,2ʹ:5ʹ,2ʺ-terthiophene]-5,5ʺ-diylbis(methanylylidene))bis(benzo[d]thiazol-2-imine) (SC3) and (6E)-N-((5-(5-(5-((E)-(4-(4-(4-fluorophenyl)thiazol-2-yl)phenylimino)methyl)thiophen-2-yl)thiophen-2-yl)thiophen-2-yl)methylene)-4-(4-(4-fluorophenyl)thiazol-2-yl)benzenamine (SC13), have the same core composed of three thiophene rings but different terminal chains of the molecules. In the imine SC3, the imine bond is followed by benzothiazole rings on both sides of the core, while in SC13, a thiazole ring separates two benzene rings, the terminal one F-substituted. The difference in molecular structure affects the electric properties of the neat imine and its mixed layers. An addition of PC71BM to the imines improves their electric conductivity. The mechanical studies focused on the stress at break and elongation showed superior behaviour compared to fullerene derivative. High pressure systematically reduces the band gap energy, Eg, from 1.68 eV at 0.16 GPa to 1.51 eV at 2.69 GPa for PC71BM, from 1.77 eV at 0.1 MPa to 1.53 eV at 4.15 GPa for SC3, and from 1.99 eV at 0.11 GPa to 1.8 eV at 3.10 GPa for SC13, as determined by the UV–Vis absorbance measurements in a diamond-anvil cell. These Eg reductions reflect the compressed intermolecular interactions that can be used to monitor the structural stability of these compounds. Based on the dielectric studies it was found that the relaxation processes registered for both imines are probably the grain boundary relaxation. Two processes also appear in the systems with PC71BM, but none of them is the one characteristic of imines. The high-frequency process has a dipole character while the low-frequency one is probably the grain boundary relaxation of these systems. The mechanism of quasi-DC conduction in various temperature ranges in the studied systems was also determined. [ABSTRACT FROM AUTHOR]

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Copyright of Przeglad Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przeglad Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przeglad Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przeglad Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Electricity storage is one of the best-known methods of balancing the energy supply and demand at a given moment. The article presents an innovative solution for the construction of an electric energy storage device obtained from an innovative photovoltaic panel made of new dye-based photovoltaic modules and newly developed supercapacitors – which can be used as an emergency power source. In the paper, for the first time, we focused on the successful paring of new dye-sensitized solar cell (DSSC) with novel supercapacitors. In the first step, a microprocessor stand was constructed using Artificial Intelligence algorithms to control the parameters of the environment, as well as the solar charger composed of six DSSC cells with the dimensions of 100×100 mm and 126 CR2032 coin cells with a total capacitance of 60 F containing redox-active aqueous electrolyte. It was proven that the solar charger store enough energy to power, i.e. SOS transmitter or igniters, using a 5 V signal. [ABSTRACT FROM AUTHOR]

The article presents the Gaussian model of the electromagnetic radiation attenuation properties of two resin systems containing 75% or 80% of a carbonyl iron load as an absorber in the 4–18 GHz range. For the attenuation values obtained in the laboratory, mathematical fitting was performed in the range of 4–40 GHz to visualize the full curve characteristics. The simulated curves fitted up to a 0.998 R2 value of the experimental results. The in depth analysis of the simulated spectra allowed a thorough evaluation of the influence of the type of resin, absorber load, and layer thickness on reflection loss parameters such as the maximum attenuation, peak position, half-height width, and base slope of the peak. The simulated results were convergent with the literature findings, allowing a much deeper analysis. This confirmed that the suggested Gaussian model could provide additional information, useful in terms of comparative analyses of datasets. [ABSTRACT FROM AUTHOR]

Copyright of Przeglad Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przeglad Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przeglad Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przeglad Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Many armies around the world showed an increasing interest for the technology of renewable energy sources for military applications. However, to profit fully from solar or wind energy, an energy storage system is needed. In this article, we present an energy storage system based on acid-lead batteries as a component of a modular generation-storage as a model of military "smart camp". We proposed a technical approach to study four different types of batteries: DEEP CYCLE, AGM, WET and VRLA in laboratory and real conditions typical for military equipment. It was observed that the best performance was observed for AGM battery in terms of the highest cold cracking amperage equal to 1205 A combined with the most compact construction and resistance to varying thermal conditions from −25 °C, 25 °C and 50 °C. Additionally, a 12-month long-term testing in real conditions revealed that AGM and VRLA showed decrease in capacity value maintaining only approx. 80% of initial value. [ABSTRACT FROM AUTHOR]

Copyright of Przeglad Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przeglad Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przeglad Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przeglad Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przeglad Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

New liquid crystalline thiophene esters, thiophene-3-yl 3,4,5-tris(n-dodecan-1-yloxy)benzoate (ThBz1) and thiophene-3-yl 3,4,5-tris[4-(n-dodecan-1-yloxy)benzyloxy]benzoate (ThBz2), were synthesized for use in lithium-ion batteries as safe, new solvent-free ionic conductors. Both compounds were synthesized in multi-step reactions and were characterized via1H, 13C NMR and FT-IR spectroscopy, confirming the formation of the desired products. ThBz1 and ThBz2 showed good thermal stability and liquid crystalline behaviour. Electrochemical tests demonstrated a wide electrochemical window of 4 V for both tested ThBz compounds. Moreover, preliminary battery tests for new electrolytes in the LiCoO2/Li4Ti5O12 system confirmed their applicability in lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Three (4,4′-((1E,1′E)-(2,5-bis(octyloxy)-1,4-phenylene)bis(ethene-2,1-diyl))bis-(E)-N-(2,5-bis(octyloxy)benzylidene)) imine derivatives were synthesized via a condensation reaction with p-toluenesulfonic acid as a catalyst. The effects of the end groups and vinylene (–HC=CH–) moieties on the structural, thermal, optical, electrochemical and photovoltaic properties of imines were investigated to check the influence of TiO2 on the imine properties. The thermal behavior of imines and their complexes with TiO2 was widely investigated using FT-IR, XRD, DSC and POM methods in order to determine the order type in the imine structure. All imines present the highest occupied molecular orbital (HOMO) levels of about −5.39 eV (SAI1 and SAI2) and −5.27 eV (SAI3) and the lowest unoccupied molecular orbital (LUMO) levels at about −3.17 eV. The difference of the end groups in the imines in each case did not affect redox properties. Generally, both oxidation and reduction are easier after TiO2 addition and it also changes the HOMO–LUMO levels of imines. Moreover, changes in the characteristic bands for imines in the region 1500–1700 cm−1 observed as a drastic decrease of intensity or even disappearance of bands in the imine : TiO2 mixture suggest the formation of a complex (C=N)–TiO2. Organic devices with the configuration of ITO/TiO2/SAIx (or SAIx : TiO2)/Au were fabricated and investigated in the presence and absence of visible light irradiation with an intensity of 93 mW cm−2. In all imines and complexes with TiO2, the generation of the photocurrent indicates their use as photodiodes and the best result was observed for SAI3 : TiO2 complexes. [ABSTRACT FROM AUTHOR]

Two bent-shaped imines (9E)-N-(3-((E)-(4-hexadecylphenylimino)methyl)benzylidene)-4-hexadecylbenzenamine (SL1) and (10E)-N-(3-((E)-(4-(perfluorooctyl)phenylimino)methyl)benzylidene)-4-(perfluorooctyl)benzenamine (SL2) were prepared by condensation reaction in N,N-dimethylacetamide to study their thermal, structural and electrochemical properties, as well as their mixtures with titanium dioxide. Chemical structure, temperature and TiO2 influences on the phase transition temperatures, enthalpy, texture and molecular dynamics of both imines were investigated by differential scanning calorimetry, polarising optical microscopy and Fourier transform middle-infrared absorption spectroscopy during heating and cooling. Changes in the surface morphology of the imines and their mixtures with TiO2 were registered by atomic force microscopy. X-ray study showed the tendency to form lamellas in the case of SL2 as an effect of the presence of two terminal perfluorinated alkyl chains connected to a polar mobile aromatic core, which resulted in microsegregation. Additionally, TiO2 influences the energy gap and HOMO-LUMO levels of imines as was detected by cyclic voltammetry. Finally, devices with two types of architectures, such as ITO/TiO2/SL1(or P3HT)/Au and ITO/TiO2/SL1:P3HT/Au were constructed and investigated under irradiation intensity of 97.7 mW/cm2. [ABSTRACT FROM AUTHOR]

A new piperazine imine, (7E)-N-((4-((E)-(4-hexadecylphenylimino)methyl) piperazin-1-yl)methylene)-4-dodecylbenzenamine, has been synthesized by the condensation of 1,4-piperazinedicarboxaldehyde with 4- hexadecylaniline. The imine was characterized by cyclic voltammetry, Fourier transform middle-infrared absorption spectroscopy and X-ray diffraction. Thermal properties of imine was analyzed by differential scanning calorimetry method during first and second heating scan at 10 and 20 °C/min. Texture of imine was investigated by polarized optical microscopy and atomic force microscopy. Furthermore, imine was blended with titanium dioxide in anatase form and fully characterized by the same methods. Piperazine imine and its mixture with titanium dioxide exhibited only a transition from crystal to isotropic state. Imine exhibits two-step reduction wave attributed to one-electron transfer in each step as was found by cyclic voltammetry. Both titanium dioxide and poly(3-hexylthiophene) change the electrochemical properties of piperazine imine, however, in different ways. Studied imine blended with titanium dioxide exhibited higher value of energy band gap than pure piperazine imine and lower Eg than pure poly(3-hexylthiophene). [ABSTRACT FROM AUTHOR]

Controlled release of photosensitive systems is widely studied because of its numerous applications. However, just a few descriptions of the mechanism of this phenomenon have been reported. The aim of this study was to investigate the behaviour of a real system based on light-sensitive α-methylstilbene-based copolyester microcapsules with vanillin as an upload under UV irradiation. For this purpose we aimed to elucidate some of the structural features of the chains by means of quantum chemical calculations applying periodic boundary conditions. Additionally, the excitation energy of an approximated model was used to verify the influence of large size and various functionalities of attached groups on the system. From the optimized structure of trans and cis isomers, it was proved that trans-to- cis isomerization can be responsible for a main chain length reduction by 20% in comparison to the initial state, thus confirming the experimental findings. Moreover, the major influence of double bonds on photoactivity of the system was justified by comparison of the calculated UV-visible spectra of both forms with empirically obtained data which were in good agreement. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

A liquid crystal polyester and two liquid crystal copolyesters containing α-methylstilbene moieties and aliphatic or aromatic spacers in the backbone were synthesized in good yields, with the aim of using them for photosensitive microcapsule preparation. The synthesized polymers were fully characterized with respect to thermal stability, type of mesophase, molecular weight and E-Z photoisomerization. Combination of monomers with different structures allowed adjustment of the polymer characteristics such as degree of crystallinity and glass transition temperature, as verified using X-ray diffraction, polarized optical microscopy and differential scanning calorimetry. Quantitative 1H NMR and UV-visible experiments were performed in order to investigate E-Z photoisomerization after photoirradiation at 364 nm. Finally, a membrane based on one of these polymers was prepared and it was found that its wettability increased on photoirradiation. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

This review presents the current state of the knowledge regarding the use of radioactive sources to generate photonic light in scintillators as converters of ionizing radiation to electricity in photovoltaic cells. The possibility of using the phenomenon of the excitation of light photons in the scintillation materials during the interaction with particles and photons of ionizing radiation was analyzed in detail. The light photons obtained in such a way can generate an electric charge in photovoltaic cells. The whole process can be named as a nuclear cell (nuclear battery). Theoretically, the use of such physical phenomena seems to be an ideal practical solution to meet the energy needs of the modern world. However, there are many physical and technical problems that limit its widespread use in practical applications. In an ideal system, the ionizing radiation sources can emit the radiation for billions of years, and the energy of particles and photons from the radiation can be converted into photons in the scintillation material, with energy suitable to generate a photoelectric effect in a photovoltaic cell. Such a cascade sequence of different physical phenomena allows, from a theoretical point of view, for the creation of a virtually inexhaustible source of electricity. This review of historical and current literature reports aims to bring closer the idea of "energy perpetuum mobile", which has troubled many scientists around the world for centuries. [ABSTRACT FROM AUTHOR]

In this review, the concept of a hybrid solar cell system, called all-weather solar cells, a new view on energy harvesting device design, is introduced and described in detail. Additionally, some critical economical, technological, and ecological aspects are discussed. Due to drastic global climate changes, traditional energy harvesting devices relying only on solar energy are becoming less adaptive, hence the need for redesigning photovoltaic systems. In this work, alternative energy harvesting technologies, such as piezoelectric and triboelectric devices, and photoelectron storage, that can be used widely as supporting systems to traditional photovoltaic systems are analysed in detail, based on the available literature. Finally, some examples of all-weather solar cells composed of dye-sensitized solar cells (DSSC) and silicon solar cells, often modified with graphene oxide or phosphors materials, as new perspective trends in nanotechnology are presented. Two types of solar cell triggers are analysed: (i) solar cells working during day and night (DSSC with phosphors materials), and (ii) solar cells working under sun and rain conditions (piezoelectric and triboelectric silicon or DSSC solar cells). [ABSTRACT FROM AUTHOR]

The one of the most important issues in constructing light-harvesting photovoltaic (PV) systems with a charge storage element is its reliable and uninterrupted use in highly variable and weather-dependent conditions in everyday applications. Herein, we report the construction and applicability evaluation of a ready-to-use portable solar charger comprising a silicon solar cell and an enhanced energy hybrid supercapacitor using activated carbon electrodes and iodide-based aqueous electrolyte to stabilise the PV power under fluctuating light conditions. The optimised electrode/electrolyte combination of a supercapacitor was used for the construction of a 60 F/3 V module by a proper adjustment of the series and parallel connections between the CR2032 coin cells. The final photo-rechargeable device was tested as a potential supporting system for pulse electronic applications under various laboratory conditions (temperature of 15 and 25 °C, solar irradiation of 600 and 1000 W m−2). [ABSTRACT FROM AUTHOR]

The crystal structure was determined for the first time for 4-[(di-p-tolyl-amino)benzylidene]-(5-pyridin-4-yl-[1,3,4]thiadiazol-2-yl)-imine (trans-PPL9) by X-ray diffraction. The imine crystallized in the monoclinic P21/n space group with a = 18.9567(7) Å, b = 6.18597(17) Å, c = 22.5897(7) Å, and β = 114.009(4)°. Intermolecular interactions in the PPL9 crystal were only weak C−H⋯N hydrogen bonds investigated using the Hirshfeld surface. The electronic and geometric structure of the imine were investigated by the density functional theory and the time-dependent density-functional theory. The properties of the imine in neutral and protonated form with camforosulphonic acid (CSA) were investigated using cyclic voltammetry, UV–vis and 1H NMR spectroscopy. Theoretical and experimental studies showed that for the 1:1 molar ratio the protonation occured on nitrogen in pyridine in the PPL9 structure, as an effect of Brönsted acid–base interactions. Thermographic camera was used to defined defects in constructed simple devices with ITO/PPL9 (or PPL9:CSA)/Ag/ITO architecture. In conclusion, a thermally stable imine was synthesized in crystalline form and by CSA doping, a modification of absorption spectra together with reduction of overheating process was observed, suggesting its potential application in optoelectronics. [ABSTRACT FROM AUTHOR]

Unoriented and oriented membranes based on dendronized polymers and copolymers obtained by chemical modification of poly[2-(aziridin-1-yl) ethanol] (PAZE) with the dendron 3,4,5-tris[4-(n-dodecan-1-yloxy)benzyloxy]benzoate were considered. DSC, XRD, CP-MAS NMR and DETA, contribute to characterize the tendency to crystallize, the molecular mobility of the benzyloxy substituent, the dendritic liquid crystalline group and the clearing transition. The orientation of the mesogenic chain somewhat hindered this molecular motion, especially in the full substituted PAZE. The fragility, free volume and thermal expansion coefficients of these membranes near the glass transition are related to the orientation and the addition of the dendritic groups. PAZE-based membranes combine both order and mobility on a supramolecular and macroscopic level, controlled by the dendritic group and the thermal orientation, and open the possibility of preparing membranes with proper channel mobility that promotes selective ionic transport. [ABSTRACT FROM AUTHOR]

Recently, use of supercapacitors as energy storage systems has attracted considerable attention. However, the literature is scarce of information about the optimization of hybrid systems, using supercapacitors as the main energy storage system. In our study, we focused step-by-step on the engineering concept of a photo-rechargeable energy storage system based on silicon solar cells and supercapacitors. In the first step, based on commercially available elements, we designed a solar charger and simulated its work in idealized conditions. Secondly, we designed appropriate electronic connections and control systems, allowing for the charging–discharging process of the energy storage system. After constructing three type of demonstrators of solar energy charger, we tested it. The novel design allowed us to achieve total available energy from solar panel energy conversion up to 93%. [ABSTRACT FROM AUTHOR]

In recent years, a great importance has been given to hybrid systems of energy generators and energy storages. This article presents the results of our research aimed at checking the possibility of connecting a photovoltaic (PV) module and a lithium-ion battery (LIB), using a simplified control module towards a cheap and efficient system. The photovoltaic modules based on crystalline silicon solar cells, tempered glass as the front layer and ethylene-vinyl acetate (EVA) copolymer as encapsulation material are the most popular type in the industry. The disadvantage of such module type is the high weight of about 15 kg/m2. The weight of PV module used in the presented energy storage system is twice as small. This new type of PV module is based on treated poly(methyl methacrylate) (PMMA) as back sheet; high transparent foil as front sheet. Changing glass layer to PMMA requires additional modification of the lamination process parameters and EVA polymer type. For this reason, an EVA polymer with reduced crosslinking temperature was used in most cases; the voltage obtained from solar panels is significantly different from the one required by battery system. Hence, voltage converters (step-up or step-down) are needed. The use of a voltage stabilizing converter (which is a kind of electrical buffer) between the solar cell and lithium-ion battery can in some cases replace the battery overcharge protection system. However, an indispensable element is the system protecting the battery from excessive discharge. The voltage converter permits direct connection between the electricity storage and power supply, which current-voltage parameters do not match. The converter's task is to change the value of current and voltage in a way that meets the requirements of the powered receiver, minimizing power losses, increasing the whole system efficiency. Photovoltaic parameters of the energy storage systems were examined in laboratory and real conditions. [ABSTRACT FROM AUTHOR]