AREAL CURRENT MATCHING OF TANDEM SOLAR CELLS

• Main Authors: KLEIMAN, RAFAEL NATHAN, YANG, JINGFENG
• Format: Patent
• Language: English; French
• Published: 08.11.2012
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGYGENERATION, TRANSMISSION OR DISTRIBUTION; SEMICONDUCTOR DEVICES; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE

There is disclosed a tandem solar cell including a bottom solar cell having an energy bandgap with Eg1 and at least a top solar cell having an energy bandgap Eg2, the energy bandgaps satisfying a relationship Eg1 < Eg2. By "top solar cell" it is meant that this is the solar cell on which light is first incident and the light enters the bottom solar cell after passing through the top solar cell, which is why the top solar cell has the largest bandgap. The bottom solar cell and the top solar cell are vertically stacked and electrically interconnected in series in which an area of the bottom solar cell is larger than an area of the top solar cell in an appropriate ratio to provide for a substantially current matched photovoltaic device for operation in a 2-terminal configuration. This tandem structure may contain more than two (2) cells and each cell may be composed of more than one solar cell. In this case the top solar cell has the largest bandgap, the bottom solar cell has the smallest bandgap, and intervening solar cells have intermediate bandgaps that descend in magnitude from the top to the bottom solar cell.