合作类型：技术     行业类别: 其他       过期时间：2016年08月14日    

德国一所大学研究所已研发出一种太阳能电池晶体硅互连技术，该技术基于激光微点焊接，不同于常规的焊接技术。目前正在寻找合作伙伴来实施这项技术。

英文原文：An institute of a German university has developed an interconnection process for crystalline silicon rear-contacted solar cells based on laser micro-spot welding. Unlike conventional technologies it does not require cost intensive metallization like silver, reduces the thermo-mechanical stress during interconnection and offers opportunities for novel cell geometries. The institute is looking for partners to implement the technology in industry with the development of a novel solar cell stringer. The German institute developed a laser-based interconnection process for aluminum metallized solar cells. The interconnection process sequence starts with the preparation of a transparent substrate, e.g. a lamination foil which also is required for the final lay-up of the module. An aluminum foil (~ 10 μm) is attached to the substrate in the required shape suitable for the cell design. The Al-metallized cells are positioned on the Al-foil and a pulsed laser beam is focused through the transparent layer into the Al-layers. A micro-spot weld forms, which interconnects the cells mechanically and electrically. The stack is then placed on a front glass covered with a lamination material. The back of the PV module is covered with a standard backsheet. Finally the stack is laminated. The institute is looking for partners to implement the technology in industry. Possible cooperation forms are license, research and/or technical cooperation agreements. The process has shown the potential for significant increase in module performance compared to standard soldering module interconnection. The ability to contact small features (300 μm) avoids inactive areas of solar cells. Further the laser welding induces lower thermo-mechanical stress than conventional soldering technologies and is therefore suitable to contact thin (less than 50 μm) silicon solar cells. These advantages are particular important for the interconnection of interdigitated back contact (IBC) solar cells, which have both contacts on the rear side and therefore avoid losses due to shading on the front side. So far different processes have been developed for IBC solar cells, which have in general the drawbacks of requiring solderable metallization like silver and of inducing high mechanical stress during the interconnection due the high thermal budget in combination with the different expansion coefficients of the used materials. The process is highly flexible and the process have also been implemented for two-side contacted solar cells and back contacted solar cells with different contact geometries. The high flexibility of the interconnection process transfers into a new flexibility for the module design offering various possibilities for significant conversion efficiency increase. Further the process totally avoids the need of silver or other cost-intensive materials and it can further reduce the material cost due to the possibility to contact thinner solar cells.