HI-PROSPECTS - HIgh resolution PRinting Of Solar Photovoltaic EleCTrode Structures

点击翻译按钮获取中文摘要

The research to be carried out by Swansea University is to understand the issues and develop solutions related to upscaling the near transparent copper grid to larger sizes. There is a significant challenge in this in that increases in sizebrings both scientific and engineering challenges. When scaling, issues such as substrate form (which can be ignored atsmall scale) become important, substrate stressing due to differential temperature profiles can lead to catastrophic failureand thus optimized curing / sintering at small scale will have to be refined as the substrate size increases. In addition thetolerance to defects and variations in deposit due to materials or processing conditions (some of which cannot becontrolled) may be insignificant at small scale but become significant as the substrate size increases. As well as processand material considerations, there are design consideration. As substrate size increases then there may be a need to alterthe nature of the deposited grid such that higher conductor density is required towards the centre of a cell / module as acharge generated at the centre of the cell will have a extended resistive path length to reach an electrode. The optimizationof this patterning and its impact is to be investigated in the work. Understanding these scale effects such that their impactcan be mitigated is critical in developing an engineering solution for large area processing of electrodes. The researchactivity will address the optimization of the line structure and geometry for large areas through modelling and in parallelperform install the system for experimental development of the ESJET over large areas. SPECIFIC will also provide lifetimetesting of the PV cells / modules manufactured in order to establish whether the copper grid has any detrimental / beneficialeffect on PV performance.In order to establish optimal grid patterning simulation software (such as PSPICE) will be used to model the geometriesand film thicknesses, their effect on the sheet resistance and its subsequent effect on performance of PV cells createdusing the fine copper patterning. This will take material data from the lab trials and estimate the geometric design andprocess windows.The clean room facilities at SPECIFIC provide an ideal test environment where glass substrate > 1m2 are routinely printedusing conventional printing techniques. The second main research activity is design and install a larger scale ESJETsystem on the glass processing line at SPECIFIC and demonstrate that the copper can be deposited to the substrate overa large area and that this substrate can be used to create a large area PV cell. This will establish the design of theinstallation based on operational / material tolerances, physical layout requirements and operational processing issues. Tocompliment the deposition requirements of the ESJET copper, the sintering process which will need to be designed andimplemented. This provides additional challenges in terms of maintaining consistent energy distributions (thermal andphotonic) over a large area. Such a development is non trivial having to take account many complex interacting parameterssuch as photonic absorbance, differential thermal expansions, thermal properties and real world intensity variations.The performance and lifetime of the PV cells will be carried out in suite of PV characterization and lifetime testing facilitiesat SPECIFIC. The standards used for these tests (illumination, RH and temperature) will be determined from the relevantstandards and in house best practice with perovskite and OPV cells. Control samples using conventional TCOs, Ag grid &TCOs combinations will also be used to identify only those degradation routes which can be attributed to the presence ofthe copper grid.