Three-junction laminated thin film solar cell and fabrication method thereof

Abstract

The invention discloses a three-junction laminated thin film solar cell, and belongs to the technical field of solar photovoltaics. The thin film solar cell aims at improving photoelectric conversion efficiency of the thin film cell and allowing the photoelectric conversion efficiency of the thin film cell to be approximate to that of a crystal cell. The thin film solar cell is characterized in that a top cell is an amorphous silicon solar cell, has an intrinsic layer energy gap of 1.7-1.8eV, and absorbs blue sunlight; the middle cell is a cadmium telluride cell, has an energy gap of about 1.45eV, and absorbs green light; and the bottom cell is a copper indium gallium selenide cell, has an energy gap of about 1.05eV, and absorbs red light. A middle layer is introduced, an optical path and optical trap structure is added, the light absorption efficiency is improved, the dividing precision can be improved by a step-by-step dividing method, the series connection and short circuit in a cell module are reduced, the product cost is lowered, and the reject rate is reduced.

Description

technical field [0001] The invention discloses a triple-junction laminated thin-film solar battery technology, which belongs to the field of solar photovoltaics. Background technique [0002] Since entering the 21st century, energy issues have always been the core issues of concern to all countries in the world. At present, fossil fuels such as coal and oil, which are in a dominant position in the energy structure, are causing environmental damage and resource depletion. Make countries commit to the research of "changing the energy structure and protecting the earth". Solar energy is the most potential among renewable energy sources, compatible with existing power technologies, and highly secure. A solar cell is a photovoltaic device that converts light into electricity. Commercial crystalline silicon solar cells are the mainstream in the photovoltaic market, and the conversion efficiency of cell modules has reached more than 15%. However, the cost and energy consumption...

AI Technical Summary

Problems solved by technology

However, an important problem faced in mass production is: whether laser or mechanical is used to scribe the P1, P2, P3 channels to form the internal series connection of the battery, the process will affect the cross-section of the transparent conductive film intermediate layer and the back electrode or The front electrodes, including between different stacks, will form conductive channels, resulting in micro-short circuit or leakage, leading to battery (or component) failure

The width of the laser marking line is related to the precision. The wider the channel, the higher the precision requirement, and it is more difficult to realize in the production process.

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