Preparation And Research Of Low Stress Photovoltaic Ribbons

With silicon cell becomes thinner?bigger, and welding temperature more higher? if continue to use tradition PV ribbon will cause the fragmentation rater higher than before in silicon cell production, that affect the battery components production cost seriously?service life and the work efficiency. So solving the existing problems of tradition PV ribbon, prepared with low significance becomes more and more important.According to the issue, we have several methods, such as adjusting process, change the interconnect tape's thermal expansion coefficient, welding methods, welding position and welding temperature and so on. And the most effective solution is to use low stressed ultra-soft PV ribbon, which characteristic is yield strength lower than 80Mpa. This essay mainly focuses on two key issues to work on and research, that is, the interconnect tape improving battery's useful life and work efficiency. In how to solving the rate of fragment, adopting combine theoretical, numerical simulation and experimental studies with each other to research the mechanism of interconnect tape welding in the process of silicon solar power produce will come into fragments; and in this way to find out a valid and reasonable measures which can low down the silicon battery fragmentation rate in the process of welding and serving. In the case of improving battery's work efficiency, we dedicated to study and find out a kind of interconnect tape which possesses the quality of small-width, large section of box construction and low series resistance. The results are as follows:1?the matrix copper strip rolling, through the calculation of rolling theory, choose hard copper wire with diameterrolling, make the rolled strip's thickness and width size to tolerance standard;the matrix copper strip annealing, comparison pot annealing and large current annealing to find effect on performance and electrical performance, mechanical, get better annealing process parameters, determining the current annealing process for low strain annealing process force interconnection with copper substrate;2?tin solder anti-oxidation performance is improved, add 0.01%earth elements into tin solder, the antioxidant properties of tin solder, the solder dross in daily production volume loss is reduced from 4%to 3.5%;3?tin copper content, through the control of hot dip galvanizing temperature, and regularly adding sulfur removal of copper. the copper content decreased from 0.3% to 0.01%;4. gas production parameters and the coating thickness, with the other parameters remain unchanged bigger thickness of gas pressure, air knife nozzle and the thinner plating range is the thick coating thickness, air knife nozzle and plating angle is negative the thick coating thickness, air knife nozzle and the tin surface the height of the thick coating thickness, production lifting faster the thick coating thickness;5?low strain characterization with force interconnection, compared with the ordinary brazing with yield strength and resistivity, the use of low stress interconnection with welding section of the fragmentation rate has declined, from 0.6% down to 0.2% the following, low resistance rate is less than 1% of the increase of the battery output power, corrosion resistance and excellent welding performance;6?interconnection with pieces of welding thermal stress, is simulated by finite element analysis software Ansys, stress were studied through the interconnection of different types with welding heat for the silicon wafer, analysis of causes of welding stress and bending capacity.This article by Kunming Sunlight limited liability company and applied to other solar companies, analyzed the relationship between PV ribbon and silicon solar cell fragmentation rate and conversion efficiency?Researched cooper substrate pressing, annealing and metallic coating by hot-dipping process, made annealed cooper strips and the optimal thickness paint-coating interconnect tape; expounded and proof ultra-soft low stressed interconnect tape can improve battery's useful life and work efficiency. It has important directive value and practice value in the production and design of silicon solar battery assembles.