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36th European Photovoltaic Solar Energy Conference and Exhibition; 1028-1031, In this work, we propose to use the copper accelerated acetic acid salt spray (CASS) test accelerated the salt mist corrosion test (IEC 61701), because there have been many reports recently that the module system in the coastal zone has been affected by corrosion. It implied the level 6 salt mist corrosion test is not enough in the coast with High temperature and humidity. The CASS test is for small moudles and aluminum frame. For the small module, we use different different materials under 24 day CASS test. It can be found the CASS test has little effect on the small module without the aluminum frame. For the aluminum frame, we have aluminum frame with different coating methods and conditions which under 6, 15, 20 and 24 days CASS test, and analyze the appearance and corrosion results. It can be observed that the general module aluminum frame shown minor pitting in 6 days. It means the aluminum frame with general condition is not resistant to the corrosion in this environment condition. Besides, the observation of the corrosion condition of the aluminum frame is not the traditional uniform corrosion, which is mainly for the pitting. The aluminum frame samples with traditional anodized coatings are less resistant to high corrosive environments.

36th European Photovoltaic Solar Energy Conference and Exhibition; 358-360, We have carried out many analyses on the accelerated light soaking testing for P-type PERC cells with and without laser light-induced regeneration (LIR) technology, including elevated temperature, intensity of the illumination and particular light source of two wavelengths 396nm and 969nm. For the non-laser LIR PERC cells, it can be found that the time of the recovery of light induced degradation (LID) shrinks down to 4hrs at elevated temperature 130°C under 1.5 sun. For the laser LIR PERC cells, it shown that the extent of the degradation after cycles of dark annealing and light soaking was still exists, the hydrogenation tool cannot completely eliminate excess hydrogen. It also indicated the 14s treatment time of laser LIR parameter is the best parameter than others time in this work. It could be demonstrated that the accelerated LID effect can be observed under high intensity and high temperatures conditions.

36th European Photovoltaic Solar Energy Conference and Exhibition; 50-53, Whether solar panels installed in the coastal area would suffer more severe PID phenomenon due to the salt spray environment or not was one of controversial debate topics recently. The sequence tests taken in past studies had not found decisive evidence to exclude or confirm the impact of external ions on PID effect. In view of this, the epoxy substrate covering on the special cell-scale module-like specimen was prepared to simulate the source of impurities in the coastal environment during PID test. Significant change in shunting degradation behavior could be observed on solar cell with Epoxy/Backsheet/EVA/Cell stacking sequence, in contrast, no obvious PID characteristic change was noticed for specimen with Epoxy/Glass/EVA/Cell structure. Furthermore, deeper analysis on the different operating temperatures and types of backsheet effect on the environmental-induced PID behavior of PV backsheets were also carried out based on the previous mentioned-notices. Results of the former experiment showed that the impurities in the epoxy could penetrate into the solar cell through the backsheet material rather than the front glass and experimental results of the later showed that thermal stability of PV backsheet at operating temperatures of testing system could dominate the degree of severity on PID behavior. Moreover, the experimental design also provided a new environmental impurities induced PID verification method.

36th European Photovoltaic Solar Energy Conference and Exhibition; 974-976, The anti-corrosion ability for PV framing materials is proposed in standard of International Electrotechnical Commission (IEC) 61701: 2011 Severity 6. It is used to understand the resistance of different PV modules to corrosion from salt mist containing Cl- (NaCl, MgCl2, etc.). The test is applied in a neutral salt mist condition of around pH 6.5~7.2, and the criteria for the test is the PV power degradation less than 5 %. According to the experiences, most PV frames can withstand the corrosion condition and pass the test without power losses and insulation failure. To simulate the real application of the environment of acid rain and cycling condition, copper accelerated acetic acid salt spray (CASS) test referred to ASTM B368 is performed to study the resistance of PV frames. In the current research, we report the corrosion behavior of various commercial anodized Al materials undergoing CASS test. Some blue crystalline salts depositing on the sample surfaces due to the copper ions. And the fluorocarbon-coated type generally shows a smooth surface without corroded pits, while the commercial anodized Al materials were detected some pits and uniform corrosion on the surface. And the non-coated Al counterpart was revealed a poor resistance that lots pits and layers peeled from the surfaces. According to the test, it is confirmed that the CASS test can be applied for fast screening the corrosion resistance of PV Al frames. A detailed research results by metallurgical procedure will be revealed for discussion.

35th European Photovoltaic Solar Energy Conference and Exhibition; 1360-1362, The amended safety requirements of PV modules is proposed in the latest edition IEC 61730-1:2016. It is noted that the distance through insulation (DTI) test replaces partial discharge test due to its authenticity to the practical applications. The insulation layers containing encapsulants and backsheet is especially concerned for its safety characteristics in the increasing system voltage of > 1000 V. According to the IEC standard, the minimum thickness of the insulation should not be less than 150 μm for a PV system of less than 1000 V, while a thickness of > 300 μm is required for a PV system of < 1500 V. To study the actual thickness of insulation layer, encapsulant/backsheet laminates are carried out to evaluate the thickness. In the current research, we report the DTI values of 2 encapsulants and 3 backsheets laminates. A polyolefin-based encapuslant is also contained for its highly demanding in the glass-to-glass PV systems. Furthermore, the triple-layer backsheets are deployed for this study. This may facilitate the solar manufacturers to control or screening the quality as IQC. This paper delivers the preparation method of DTI samples, and their testing results are also revealed for discussion.

33rd European Photovoltaic Solar Energy Conference and Exhibition; 1698-1701, The issue of typhoon has received considerable critical attention due to the associated strong winds generally damage PV modules severely. Previous IEC standards have examined the effect of static uniform-loads (IEC 61215-2:2016) or dynamic uniform-loads (IEC TS 62782:2016), but overlooked the wind loads with moment effect or non-uniform loads on PV module. In this paper, we develop an analytical model about a mean extended wind load (MEWL) test method, and a non-uniform dynamic mechanical load (NUDML) system, which can simulate the wind action on PV module by uneven mechanical loads. Results of this study also provide a severity test considering the environmental condition such as wind velocity (V), wind direction angle () and inclined angle () of PV module.

33rd European Photovoltaic Solar Energy Conference and Exhibition; 1533-1536, Emerging photovoltaic, including of organic solar cell and dye-sensitized solar cell, are high-potential PV products used for energy harvesting, especially in the indoor illumination applications. This paper aims to examine the standardization research of pivot SEMI emerging PV standards, which were developed by SEMI OPV and DSSC task force in Taiwan during 2013 to 2017. This work consists of three international standards in detailed specifications, including SEMI PV57, SEMI PV69 and SEMI PV76. PV57 is designed to evaluate solar cell’s characteristics without capacity effect for I-V measurement. PV69 is designed to provide a suitable statistic method for SR evaluation by solving the slow response time problem, and proposes a guideline to correct performance data measured on an isothermal platform under STC. Therefore, after harmonizing both PV57 and PV69 in solving the hysteresis problem due to capacity effect and getting the reliable I-V, PV76 improves the existing durability tests, e.g., IEC 61646 for thin-film product, towards a more complete simulation or real operating conditions of emerging PV to inspect the product’s defect or weakness in early stage. Consequently, these standardizations have provided the contributions to alleviate the performances of emerging PV, and influence the relevant reliability aspect in a longterm perspective.

33rd European Photovoltaic Solar Energy Conference and Exhibition; 1770-1773, Ethyl vinyl acetate (EVA)and backsheetarekey materialstothe high reliabilityand performanceof solar module. The complicated polymer compositions of EVA and backsheet are sensitive to humidity and UV light, thus resulting in degradation. The IEC standards concerning the polymer materials weatherability and durability usually take few months for testing. To reducethe testing duration, EVAand backsheetinspection is carried out to evaluate the applicability for solar module.The EVA inspection including5 testmethods in accordance with IEC 62788 standard,accelerated aging tests,andlamination conditions.The tests samples could be in the forms of cured status orraw materials.This may facilitate the solar manufacturers asincoming quality controlorscreening. In this research, 5 EVA and 5 backsheet samples are prepared for test. The results show a significant differentiation of the qualified materials from the failed samples. This paper delivers the5testing methods for EVA and backsheet materials, and their testing results are also revealed for discussion.

32nd European Photovoltaic Solar Energy Conference and Exhibition; 1363-1366, Nowadays, wireless communication networks focus on indoor applications, Internet of Things (IoT), sensor networks, etc., use batteries as their source of energy. However, batteries have a limited lifetime and to be replaced regularly. The lifetime often is one key limiting factor for the device. Replacing the battery always outweighs the most cost of the device itself. However, if the device itself could be able to harvest energy from renewable resources in the environment, the lifetime of the device will be many times over. The feasibility of PV for indoor low power applications has already been demonstrated, for phone chargers, computer mice and indoor positioning systems. The PV cells for different applications on earth to be rated by their power output under standard test conditions (STC). However, the STC are not relevant for indoor applications. Typically, the light intensity under artificial lighting conditions found in offices and factories is less than 5 W/m2 as compared to 100–1000 W/m2 under outdoor conditions, depending on the type of light source and its distance. Characterization of emerging PV requires variable indoor light source and very slow temporal response. In this study, we also made a comparison for different emerging PV in light levels indoor environments. The characterization after test showed it is not necessary to measure performance under all typical artificial light sources. Therefore, we propose the reasonable comment about each solar cell measured by indoor light sources for its characterization and application.

32nd European Photovoltaic Solar Energy Conference and Exhibition; 1360-1362, This paper aims to summary the research of pivot SEMI standards about organic photovoltaic (OPV) and dye-sensitized solar cell (DSSC), which are developed by SEMI OPV and DSSC task force (TF) in Taiwan during 2013 to 2016. This work proposes three test methods in detailed specifications for OPV/DSSC product, including current-voltage (I-V), spectrum response (SR) and durability. I-V measurement (SEMI PV57 [1]) is to evaluate product’s characteristics without capacity effect for OPV/DSSC. SR evaluation (SEMI PV69 [2]) is to provide a suitable statistic method after solving the slow response time problem for OPV/DSSC, and proposes a guideline to correct performance data measured on an isothermal platform under STC. Based on these two released standards, furthermore, durability test (SEMI Doc. 5598 [3]) for OPV/DSSC can improve the existing aging tests towards a real operating condition, in order to determine its performance accurately and inspect the product’s defect or weakness in early stage. Through these standardizations, results can help industry to get reliable performances of OPV/DSSC, and influence the relevant reliability aspect in a long-term perspective.

32nd European Photovoltaic Solar Energy Conference and Exhibition; 1357-1359, Characterizations of organic photovoltaic (OPV) and dye-sensitized solar cell (DSSC) are important in order to determine the reliable measurements of cell efficiencies and inspect the product’s defects in early stage. This paper aims to improve the existing durability tests towards a real operating condition for OPV/DSSC. This work developed a durability test according to parallel tests such as thermal cycle (TC), damp heat (DH), light soaking (LS) and combined test (TC50+DH). Each test condition has the stress specification, which differs with IEC 61646 designed for thin-film device. Furthermore, results were applied for SEMI Doc. 5598 [1] to develop an evaluation principle of OPV/DSSC for PV industries to follow up, and harmonized the test guidelines of current-voltage (SEMI PV57 [2]) and spectrum response (SEMI PV69 [3]). Guidance on the choice of the suitable test conditions of durability test in the detailed specification is given. Consequently, this standardized test method for OPV/DSSC can help industry to get reliable performances of emerging PV, and influence the relevant reliability aspect in a long-term perspective.

The Taiwan mountain belt is generally thought to develop above a shallow, through-going basal detachment confined to within the sedimentary cover of the Eurasian continental margin. Recently acquired surface geology, when combined with seismic tomography, earthquake hypocenter, and gravity data suggest, however, that basement is also involved in the deformation in south-central Taiwan. Since basement does not crop out in south central Taiwan, we adopt a P-wave velocity of 5.2 km/s has a proxy for the basement-cover interface and use it as a reference horizon. This interpretation is then tested as a density contrast by 3D modeling of the Bouguer anomaly data. The good fit between the two suggests that this surface provides a reasonable proxy as an interpretation for the top of the basement in what follows. The data suggests that, in the west, beneath the Coastal Plain and the Western Foothills, the mountain belt is evolving above a southward deepening level of detachment that is illuminated by sub-horizontal clusters of earthquake hypocenters located near the basement-cover interface. In much of the study area, this detachment appears to be below the depth of the basal thrust determined from geological constraints provided by the thrust system mapped at the surface. Furthermore, when viewed in a northwest-southeast orientation, the hypocenters cluster that defines the detachment appears to mimic the rugose extensional fault architecture imaged in the off shore to the west of Taiwan. This suggests that pre-existing faults on the margin, although oriented at a high angle to the convergence direction, are playing an active role in the development of thrust belt while still not being completely inverted. Eastward, the detachment at the basement-cover interface joins with an east-dipping hypocenter cluster that is interpreted to form a ramp that extends to greater than 20 km depth, into the middle crust. Above this ramp, basement rocks (P-wave > 5.2 km/s) are uplifted to near the surface, forming a basement culmination beneath the Hsuehshan and Central ranges. The uplift of these basement rocks, together with the juxtaposition of higher metamorphic grade rocks across the Shuilikeng, Lishan and Chaochou faults suggests that these faults form a linked fault system that extends downward into the middle crust at the location of the ramp.

26th European Photovoltaic Solar Energy Conference and Exhibition; 376-379, This paper presents the failure analyses of crystalline rear side solar cells interconnected by electrical conductive adhesive (ECA). The electrical conductive adhesive was characterized by differential scanning calorimetry (DSC), thermogravimetry analyser (TGA) for interconnecting process of solar cells. And the performance and reliability of the solar module in as-laminated and post-aging status were characterized by the solar flasher system. Detailed microstructure analyses focusing on the connecting interfaces were taken by scanning microscope/energy dispersive spectroscopy (SEM/EDX), X-ray diffraction (XRD). SEM/EDX showed the high strength sample was detected significant Ag content around 82.39 at. %, while lower Ag (55.94%) and oxygen (44.06%) were measured in failed sample. It is suggested that the oxidation of Ag occurred during the connecting process. For the electrical performance, the as-laminated module decreased from 9.85Wp to 9.04Wp, indicating degradation in power should be due to the oxidation of Ag.

26th European Photovoltaic Solar Energy Conference and Exhibition; 2184-2188, This paper presents the performance of rear side solar modules of 5 inch crystalline solar cells by an innovating assembly structure with epoxy-based electrical conductive adhesive (ECA). The innovating module assembly structure for back contact solar module is proved to successfully prevent the shunting failure when back contact solar cells interconnect. According to the comparison between the innovating module structure and as-laminated back contact solar module, it is revealed that power loss for the innovating module structure and as-laminated solar cell module package structures in a series connection were 1.57%, and 5.33%, respectively. The solar module by innovating assembly should reduce cell power loss by about 70.5%. On the other hand, fill factor (FF) reduction of the innovating assembly module and the as-laminated solar cell module package structures were about 0.46% and 3.52%, respectively. Compared to the as-laminated solar cell module package structures, the innovating assembly module remained high shunt resistance (Rsh) and smaller series resistance (Rs), thereby reducing FF loss during packaging processes. The comparison results illustrated the innovating assembly module structure should significantly improve the package loss of the rear side cells in a series connection.

25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 1484-1487, Electromigration behavior of polycrystalline solar cell strings with lead SnAgPb and lead-free SnAgCu ribbons were studied at 1000C for 100hr, 250hr, and 500hr by scanning electrical microscope (SEM). The testing samples were connected to a multi-channel power supply with current 7 and 10 amper (A), and series resistance (Rs) of the solar strings were characterized by four wire method. The results showed that series resistance of the sample were initially 0.020 and then generally increased with the increasing testing time, while an abnormal increase of the string loading with 7A for 500hr was detected as 0.026. Furhtermore, the samples loading with high current (10A) have higher Rs values than those loading with 7A. According to the SEM analyses, the formation of intermetallics (IMCs) was detected in the solder/Cu foil interface. The thickness and the morphology of the intermetallic layer were affected by the testing time, in which the IMC particles was detected in the sample loading with 7A current for 100hr, while a continuous and thicker layer was revealed in the sample loading at high current density for longer testing. Furthermore, large whisker-shaped IMCs were exclusively detected in the lead sample loading with 7A current for 500hr, indicating the high Rs value was predominantly affected by intermetallics.

24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 3571-3572, Electrical performance of hydrogenated amorphous silicon (a-Si:H) and polycrystalline photovoltaic (c-Si) modules at temperature ranging from 298K to 338K were investigated and compared with various parameters. In order to realize the I-V performance affected by cell temperature, shunt resistance (Rsh), and series resistance (Rs), fill factor (FF) value was reckoned to evaluate the module performance. In general, the maximum power (Pmax), open circuit voltage (Voc), and short circuit current (Isc) for a-Si:H and c-Si modules showed similar tendencies when heating up the modules. However, a distinct Rs difference of c-Si and a-Si:H module were detected when heating up the modules. It is very likely that the decreasing FF of c-Si module was mainly dominated by the increasing Rs; reversely, the increasing FF of a-Si:H module was controlled by the decreasing Rs.

Using x-ray absorption spectroscopy at the Ru-$L_{2,3}$ edge we reveal that the Ru$^{4+}$ ions remain in the $S$=1 spin state across the rare 4d-orbital ordering transition and spin-gap formation. We find using local spin density approximation + Hubbard U (LSDA+U) band structure calculations that the crystal fields in the low temperature phase are not strong enough to stabilize the $S$=0 state. Instead, we identify a distinct orbital ordering with a significant anisotropy of the antiferromagnetic exchange couplings. We conclude that La$_{4}$Ru$_{2}$O$_{10}$ appears to be a novel material in which the orbital physics drives the formation of spin-singlet dimers in a quasi 2-dimensional $S$=1 system., Comment: 5 pages, 4 figures, and 1 table

Utilizing a sum rule in a spin-resolved photoelectron spectroscopic experiment with circularly polarized light, we show that the orbital moment in LaTiO3 is strongly reduced from its ionic value, both below and above the Ne el temperature. Using Ti L2,3 x-ray absorption spectroscopy as a local probe, we found that the crystal-field splitting in the t2g subshell is about 0.12-0.30 eV. This large splitting does not facilitate the formation of an orbital liquid.

We report on a X-ray absorption spectroscopic (XAS) study on a thin film of La0.7Ce0.3MnO3, a manganite which was previously only speculated to be an electron doped system. The measurements clearly show that the cerium is in the Ce(IV) valence state and that the manganese is present in a mixture of Mn2+ and Mn3+ valence states. These data unambiguously demonstrate that La0.7Ce0.3MnO3 is an electron doped colossal magnetoresistive manganite, a finding that may open up new opportunities both for device applications as well as for further basic research towards a better modelling of the colossal magnetoresistance phenomenon in these materials., 4 pages, 3 figures, revised version