Bus ribbon welding process for thin film solar cell

Abstract

The invention discloses a bus ribbon welding process for a thin film solar cell and belongs to the field of semiconductor photoelectricity. The process uses a thin film solar cell with an aluminum back electrode, at least two drainage ribbons, namely the left drainage ribbon and the right drainage ribbon, are arranged on the back electrode of the thin film solar electrode, the left drainage ribbon, the right drainage ribbon and the back electrode are welded by ultrasound, a left bus ribbon and the left drainage ribbon are hot-welded to form a welding point, a right bus ribbon and the right drainage ribbon are hot-welded to form another welding point, the left drainage ribbon and the right drainage ribbon are copper and aluminum composite ribbons, and the left bus ribbon and the right bus ribbon are tinned copper ribbons. Therefore, welding speed and quality can be guaranteed effectively, the bus crosspoint is firm and reliable, and the problems of bussing cost and service life of thin film cells are solved effectively.

Description

technical field [0001] The invention relates to a confluence welding process of a thin film solar cell, in particular to a confluence welding process of a thin film solar cell whose back electrode is made of aluminum, and belongs to the field of semiconductor optoelectronics. Background technique [0002] As the world's energy crisis and environmental pollution become more and more serious, people have accelerated the research on solar photovoltaic power generation technology, so solar cell manufacturing technology has developed rapidly, and thin-film solar cells, as an important branch of solar cells, have developed in recent years. Rapidly, its categories include amorphous silicon, amorphous silicon germanium, microcrystalline silicon, or double-junction or multi-junction stacked thin-film batteries composed of them, cadmium telluride thin-film batteries, copper indium gallium selenide thin-film batteries, etc., At present, the back electrode film layer of thin-film solar ...

AI Technical Summary

Problems solved by technology

The advantage of the combined material and method is that the process is simple and the cost of materials is low, and the disadvantage is that the welding of the confluence intersection is not firm, and the battery is very hot at the confluence intersection under long-term working conditions, which may easily lead to battery failure.

[0004] (2) Doped zinc oxide film back electrode, commonly used tin-plated copper strip, silver paste, its usage is: the tin-plated copper strip is bonded to the zinc oxide film back electrode with silver paste, and the tin-plated copper strip for confluence and drainage The intersection of tinned copper strips is heat-welded. The advantage of this combined material and method is that the welding is firm and reliable, but the disadvantages are that the process is complicated, the silver paste and other materials are expensive, and it is necessary to add white paint as a reflective layer, and the cost is also high. will increase

[0005] (3) Silver film (or nickel-vanadium film) back electrode, commonly used tin-plated copper strip, its usage is: solder the tin-plated copper strip for drainage to the back electrode of silver film (or nickel-vanadium film) by heat welding The intersection of the tinned copper strip for confluence and the tinned copper strip for drainage is heat welded. The advantage of this combined material and method is that the welding is firm and reliable. The disadvantage is that the process is more complicated, and the silver film (or nickel vanadium film) is expensive

The advantage of the combined material and method is that the process is simple, and the disadvantage is that the aluminum foil conductive tape or the copper foil conductive tape is expensive

[0007] All of the above processes have shortcomings such as unguaranteed welding quality and expensive materials to varying degrees, and it is difficult to meet the current market requirements for long-life, low-cost and large-scale power generation of thin-film batteries.

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