Light splitting manufacturing process for five-junction solar cell system

Abstract

The invention discloses a spectrum-dividing fabrication method of a five-junction solar battery system. The method is characterized in that solar spectrum are divided by two spectrum-dividing devices into a continuous high-energy region, a sub-high-energy region and a low-energy region sequentially; a single junction structure is adopted in the high-energy region to match the high-energy spectra; and two double-junction tandem structures with different band gap widths are adopted in the sub-high-energy region and the low-energy region to match the sub-high-energy spectra and the low-energy spectra, so as to achieve absorption and conversion of full-spectrum energy of the solar light. By adopting the spectrum-dividing devices, the two-plus-two-plus-one structure, the solar battery system can absorb and utilize energy of the solar spectral bands matched with the band gap width of the material, thereby reducing thermal loss in photoelectrical conversion, maximally realizing solar full-spectrum absorption and improving the photoelectrical conversion efficiency. Meanwhile, the solar battery system can obviate low cost resulting from the adoption of a plurality of different substrates in a mechanical tandem solar battery system, and can effectively solve the problem of lattice mismatch during the growth of single four-junction tandem semiconductor battery material.

Description

technical field [0001] The invention relates to the photovoltaic technical field of solar energy utilization, in particular to the design and manufacture of a light splitting structure of a solar cell system. Background technique [0002] The increasing shortage of conventional energy sources such as oil and coal and the earth's ecological problems caused by their over-exploitation are the greatest challenges facing mankind in the 21st century. As a clean and renewable energy utilization technology, high-efficiency solar power generation technology has continuously made breakthroughs. Crystalline silicon solar cells, amorphous silicon solar cells, amorphous silicon thin-film solar cells, III-V compound semiconductor solar cells, II-VI compound semiconductor polycrystalline thin-film solar cells, etc. More and more solar cell technologies are maturing . The continuous improvement of photoelectric conversion efficiency and the continuous reduction of manufacturing costs have...

AI Technical Summary

Problems solved by technology

However, the practice so far shows that the photovoltaic technology represented by the InGaP / (In)GaAs / Ge triple-junction tandem solar cell still cannot achieve the best match with the solar spectrum; to match the solar spectrum to the greatest extent, it is necessary to Adding more junctions with different bandgaps to this triple junction cascaded cell

Although the bandgap width can be ideally matched, the theoretical efficiency improvement is often limited by problems such as lattice constant mismatch between different semiconductor materials and the resulting stress defects, resulting in directly grown monolithic four-junction cascade The highest efficiency of solar cells is only 35.7%

It is very difficult to grow solar cells with more than three junctions at the same time, and the growth yield of materials is low and the cost is expensive

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