Multijunction solar cell assembly for space applications

A solar cell assembly including a terminal of first polarity and a terminal of second polarity comprising:

• a first discrete solar cell including a top contact connected to the terminal of the first polarity, and a bottom contact;
• a second discrete solar cell disposed spaced apart from, mounted adjacent to, and with respect to the incoming illumination, parallel to the first discrete solar cell, including a tandem vertical stack of at least a first upper solar subcell, a second solar subcell, and a bottom solar subcell, the first upper discrete subcell of the second discrete solar cell having a top contact connected to the terminal of the first polarity, the bottom solar subcell of the second discrete solar cell having a top contact, and a bottom contact connected to the terminal of the second polarity;
• and
• an interconnect arrangement electrically connecting the first and second discrete solar cells, the first and second discrete solar subcells each having a top contact and a bottom contact, wherein the bottom contact of the second solar subcell of the second discrete solar cell is electrically connected to the top contact of the bottom subcell of the first discrete solar cell so that the current generated in the first and second solar subcells of the second discrete solar cell flows into and through the bottom solar subcell of the first discrete solar cell, and the bottom contact of the bottom solar subcell of the first solar cell is connected to the top contact of the bottom solar subcell of the second discrete solar cell that the current then flows into the bottom solar subcell of the second discrete solar cell, so that the cumulative current generated in both (i) the first, second and bottom solar subcells of the first solar cell, and in (ii) the first and second solar subcells of the second discrete solar cell, flows into and through the bottom subcell of the second solar cell, and thereafter into the bottom contact of the bottom solar subcell of the second discrete solar cell.

A method of forming a solar cell assembly including a terminal of first polarity and a terminal of second polarity comprising:

• forming a first discrete solar cell including a top contact connected to the terminal of first polarity, and a bottom contact;
• forming a second discrete solar cell disposed spaced apart from, mounted adjacent to, and with respect to the incoming illumination, parallel to the first discrete solar cell, the second discrete solar cell including a tandem vertical stack of at least a first upper solar subcell, a second solar subcell, and a third bottom solar subcell, the first upper subcell of the second discrete solar cell having a top contact connected to the terminal of first polarity, the third bottom subcell of the second discrete solar cell having a top contact, and a bottom contact connected to the terminal of second polarity;
• and
• connecting the bottom contact of the first solar cell in a series electrical circuit with the third subcell of the second discrete solar cell so that the interconnection of the first and second discrete solar cells forms a solar cell assembly.