Parallel interconnection of neighboring space-qualified solar cells via a common back plane

Patent metadata

Field	Value
Publication number	US-2018138352-A1
Application number	US-201815868296-A
Country	US
Kind code	A1
Filing date	Jan 11, 2018
Priority date	Apr 7, 2014
Publication date	May 17, 2018
Grant date	—

Abstract

A solar cell assembly for space application comprising a plurality of space-qualified solar cells and a support, the support comprising a conductive layer. The conductive layer is divided into a first conductive portion and a second conductive portion. Each space-qualified solar cell of the plurality of space-qualified solar cells comprising a front surface, a rear surface, and a first contact in correspondence with the rear surface. Each one of the plurality of space-qualified solar cells is placed on the first conductive portion with the first contact electrically connected to the first conductive portion so that the space-qualified solar cells are connected in parallel through the first conductive portion. A second contact of each space-qualified solar cell can be connected to the second conductive portion. The two conductive portions serve as bus bars of the space-qualified solar cell assembly.

First claim

1 . A method of preparing a solar cell array for space applications, the method comprising:
forming a plurality of III-V compound semiconductor multijunction space-qualified solar cells optimized for operation at AM0 including metallic bonding pads on the top surface thereof, each space-qualified solar cell of the plurality of space-qualified solar cells comprising a front surface, a rear surface, and a first contact in correspondence with the rear surface; forming a polyimide film having a thickness of 1 mil to 4 mils and a conductive layer having a thickness of 1 micrometer to 50 micrometers attached to the polyimide film in an adhesive-less manner to mitigate outgassing, the conductive layer comprising a first conductive section and a second conductive section separated from the first conductive section; forming a conductive bonding material directly adjacent the first conductive section; positioning each space-qualified solar cell of the plurality of space-qualified solar cells directly adjacent the first conductive section, or directly adjacent the conductive bonding material directly adjacent the first conductive section; electrically connecting the first contact of each solar cell of the plurality of solar cells directly, or solely through the conductive bonding material, to the first conductive section so that the plurality of solar cells is connected in parallel through the first conductive section; disposing a ceria doped borosilicate glass supporting member that is 4 mils in thickness on a surface of each of the semiconductor solar cells; and welding interconnects composed of a silver-plated nickel-cobalt ferrous alloy material to the metallic bonding pads on each solar cell, wherein each space-qualified solar cell of the plurality of space-qualified solar cells is a rectangular or substantially square space-qualified solar cell having at least one III-V compound semiconductor layer and having a surface section of less than 1 cm 2 .

2 . A method as defined in claim 1 , wherein each solar cell of the plurality of solar cells comprises a second contact, each solar cell of the plurality of solar cells being connected to the second conductive section via the second contact of each solar cell of the plurality of solar cells by an interconnect connecting the second contact of each solar cell of the plurality of solar cells to the second conductive section.

3 . A method as defined in claim 2 , wherein the first conductive section and the second conductive section are interconnected by means of at least one diode.

4 . A method as defined in claim 3 , wherein the at least one diode comprises a top side terminal and a rear side terminal, the at least one diode being placed on the second conductive section with said rear side terminal of the at least one diode electrically coupled to the second conductive section, the top side terminal of the at least one diode being electrically coupled to the first conductive section.

5 . A method as defined in claim 3 , wherein the at least one diode comprises a top side terminal and a rear side terminal, the at least one diode being placed on the first conductive section with the rear side terminal of the at least one diode electrically coupled to the first conductive section, the top side terminal of the at least one diode being electrically coupled to the second conductive section.

6 . A method as defined in claim 2 , wherein the first conductive section and the second conductive section are electrically isolated from each other by at least one groove traversing the conductive layer.

7 . A method as defined in claim 6 , wherein the groove follows a path comprising a plurality of segments arranged one after the other, each segment extending at an angle with respect to a preceding segment and/or with respect to a following segment.

8 . A method as defined in claim 6 , wherein the groove comprises a plurality of segments, at least one of said segments extending in parallel with another one of said segments.

9 . A method as defined in claim 6 , wherein at least one portion of the groove follows a substantially meandering path.

10 . A method as defined in claim 2 , wherein the second conductive section comprises a plurality of substantially elongated subportions that extend between subportions of the first conductive section.

11 . A method as defined in claim 2 , wherein the surface section of the first conductive section is larger than the surface section of the second conductive section.

12 . A method as defined in claim 2 , wherein the plurality of solar cells placed on the first conductive section form a plurality of rows of solar cells, each solar cell of the plurality of solar cells being connected to a subportion of the second conductive section extending between two rows of solar cells.

13 . A method as defined in claim 1 , wherein each solar cell of the plurality of solar cells is electrically connected to the first conductive section solely through a conductive bonding material.

14 . A method as defined in claim 13 , wherein the conductive bonding material is an indium alloy.

15 . A method as defined in claim 14 , wherein the bonding material is indium lead.

16 . A method as defined in claim 1 , wherein the conductive layer comprises copper.

17 . A method as defined in claim 1 , wherein the first contact of each solar cell of the plurality of solar cells comprises a conductive layer extending over a substantial portion of the rear surface of each solar cell of the plurality of solar cells.

18 . A solar cell module comprising a plurality of solar cell subassemblies, each of said solar cell subassemblies comprising the method of preparing a solar cell array for space applications as defined in claim 1 .

19 . A method of preparing a solar cell assembly designed for space applications, the method comprising:
forming a plurality of III-V compound semiconductor multijunction space-qualified solar cells optimized for operation at AM0 including metallic bonding pads on the top surface thereof each solar cell of the plurality of solar cells comprising a front surface, a rear surface, a first contact in correspondence with the rear surface, and a second contact; forming a polyimide film having a thickness of 1 mil to 4 mils and a copper conductive layer having a thickness of 1 micrometer to 50 micrometers attached to the polyimide film in an adhesive-less manner to mitigate outgassing, the conducting layer comprising a first conductive section and a second conductive section separated from the first conductive section; forming at least one groove traversing the conductive layer, the groove comprising a plurality of segments, at least one of said segments extending in parallel with another one of said segments so that the groove electrically isolates the first conductive section and the second conductive section from each other; forming, within the second conductive section, a plurality of substantially elongated subportions that extend between subportions of the first conductive section, wherein the first conductive section has a larger surface section than the surface section of the second conductive section; forming, at the first contact of each solar cell of the plurality of solar cells, a conductive layer extending over a substantial portion of the rear surface of each solar cell of the plurality of solar cells; placing each solar cell of the plurality of solar cells directly adjacent a conductive bonding material that is directly adjacent the first conductive section, and electr

Assignees

• Solaero Tech Corp

Inventors

• Aiken Daniel
• Derkacs Daniel

Classifications

• H01L31/0725

  Electricity · mapped topic

• H01L31/0508

  Electricity · mapped topic

• H01L31/184 Primary

  Electricity · mapped topic

• H01L31/0512

  Electricity · mapped topic

• H01L31/0481

  Electricity · mapped topic