Terrestrial concentrator solar cell module
AssigneeThe Boeing Company
InventorsLewis M. Fraas, Nurullah Mansoori, Namsoo P. Kim, James E. Avery
Life of this patent
Estimating the term…
Abstract
Solar cells, particularly GaAs/GaSb tandem solar cells, are mechanically and electrically connected in the form of a string using a flexible circuit tape and mounted in optical alignment with solar energy concentrators in a module. A heat spreader body is attached to each cell unit as part of a heat sink and the cells are precisely positioned to provide optical alignment. The flexible circuit tape is formed by conductive strips sandwiched between layers of polymer dielectric tape and provided with tabs at predefined holes in the tape for bonding to current carrying surfaces of concentrated sunlight tandem solar cell units.
Claims36
A flexible circuit tape comprised of a base layer of electrical insulating material, parallel strips of electrically conductive foil mounted on said base layer, said circuit tape having a plurality of apertures at spaced intervals along a longitudinal direction of said tape, each of said strips of electrically conductive material having terminal portions extending free of said base layer at each aperture to have opposite surfaces that are adapted for electrical connection to an upper or lower surface of concentrated sunlight photovoltaic cells positioned in said apertures to collect electrical power generated by said cells, and an upper layer of electrical insulating material covering said foil strips.
A flexible circuit tape comprised of a base layer and an upper layer of electrical insulating material, an electrically conductive foil that is patterned in the form of parallel strips sandwiched between said base and upper layers, said circuit tape having a plurality of apertures at spaced intervals along a longitudinal direction of said tape, said strips of electrically conductive material having portions exposed at each aperture that are adapted for electrical connection to concentrated sunlight photovoltaic cells positioned in said apertures to collect electrical power generated by said cells;
- and
- said upper layer of insulating material having a mirror surface for reflecting radiant energy for protecting the tape against damage due to exposure of high intensity radiant energy on said mirror surface.
A flexible circuit solar cell array comprising:
- a plurality of discrete concentrated sunlight photovoltaic cell units;
- a flexible tape having a base of electrically non-conductive material supporting parallel strips of electrically conductive material;
- said tape base having spaced apertures that are positioned at each of said cell units;
- means for connecting the strips of conductive material to different current carrying surfaces of said cell units for collecting in said strips electrical power generated by said cell units;
- said parallel strips of conductive material extending longitudinally along opposite sides of said tape and being electrically connected to different current carrying surfaces on said cell units;
- and
- said strips being made of copper foil and containing tabs which extend transversely of the tape to be free of the non-conductive material of the tape, wherein the tabs have a surface that has bonding properties that are more favorable for bonding to cell contact surfaces than copper and said surfaces of the tabs having favorable bonding properties being bonded to the current carrying surfaces of said cell units.
A flexible circuit solar cell array comprising
- a plurality of discrete concentrated sunlight photovoltaic cell units;
- a flexible tape having a base of electrically non-conductive material supporting parallel strips of electrically conductive material;
- said tape base having spaced apertures that are positioned at each of said cell units;
- means for connecting the strips of conductive material to different current carrying surfaces of said cell units for collecting in said strips electrical power generated by said cell units;
- said parallel strips of conductive material extending longitudinally along opposite sides of said tape and being electrically connected to different current carrying surfaces on said cell units;
- said strips being made of copper and containing tabs which extend transversely of the tape, wherein the tabs have a surface that includes gold and the gold containing surfaces of the tabs are bonded to the current carrying surfaces of said cell units;
- the photovoltaic cell units each comprise a tandem stacked upper cell and lower cell of different semiconductive materials with each cell having two terminals and producing a different voltage;
- and
- the two terminals of a first plurality of said upper or lower cells are connected electrically in series with additional tabs that extend longitudinally into said spaced apertures.
A flexible circuit solar cell array comprising:
- a plurality of discrete concentrated sunlight photovoltaic cell units;
- a flexible tape having a base of electrically non-conductive material supporting parallel strips of electrically conductive material;
- said tape base having spaced apertures that are positioned at each of said cell units;
- means for connecting the strips of conductive material to different current carrying surfaces of said cell units for collecting in said strips electrical power generated by said cell units;
- said parallel strips of conductive material extending longitudinally along opposite sides of said tape and being electrically connected to different current carrying surfaces on said cell units;
- said strips being made of copper and containing tabs which extend transversely of the tape, the tabs have a surface that includes gold and the gold containing surfaces of the tabs are bonded to the current carrying surfaces of said cell units;
- and
- an upper layer of said flexible tape having a mirror surface for reflecting radiant energy for protecting the tape against damage due to exposure of high intensity radiant energy positioned on said mirror surface.
A solar cell module having a plurality of discrete cell units wherein each cell unit constitutes a tandem cell comprising an upper cell of a first semiconductive material and a lower cell of a second semiconductive material, said module comprising:
- a housing having a base and an upper portion;
- said discrete solar cell units being mounted on the housing base and interconnected into a two terminal device by electric current conducting members carried on a flexible polymeric carrier tape;
- primary outer lens elements supported by said housing upper portion;
- a secondary radiant energy concentrating element associated with each primary lens element for protecting the carrier tape against incident light, said secondary element being supported by said housing at a position adjacent to but spaced from the solar cell unit;
- each of said solar cell units being thermally coupled to the base;
- and
- parallel spaced strips of conductive material carried by said tape with means for separately connecting said strips to predetermined contact surfaces of the upper and lower cells of each cell unit.
A solar cell module comprising:
- a housing having primary and secondary light focusing elements;
- a plurality of rows of cell units mounted on said housing, each cell unit being associated with respective primary and secondary light focusing elements;
- each cell unit comprising a mechanically stacked tandem cell housing, an upper cell made of a first semiconductive material, a lower cell made of a second semiconductive material;
- exposed current carrying surfaces connected respectively to the upper and lower cells;
- means including a flexible electrical circuit tape comprising polymeric insulating material carrying a plurality of strips of electrical conducting material secured to a plurality of said cell units to form a string of cell units;
- a separate heat spreader body mounted in a thermally conducting relation with each of said cell units;
- and
- means for mounting said heat spreader bodies in a thermally conductive relationship with said housing.
A plurality of tandem solar cell units connected together and mounted in a housing, each of said units comprising:
- an upper cell made of a first semiconductive material with current carrying surfaces on opposite sides thereof;
- a lower cell made of a second semiconductive material with current carrying surfaces on opposite sides thereof;
- means for stacking said lower cell in optical alignment under said upper cell;
- and
- a flexible circuit tape including electrical conductors connected to said current carrying surfaces for matching the voltages from said cells and collecting electrical power generated by said cell units, said carrier comprising a flexible tape of polymer material supporting parallel strips of electrically conductive material, said tape having spaced apertures at each of the cell units, and means for connecting the strips of conductive material to different current carrying surfaces of said cell units for collecting said electrical power.
A process for manufacturing a solar cell module in a housing having a base, comprising:
- providing discrete tandem photovoltaic cell units which have upper and lower cells each having opposed current carrying surfaces, said units being mounted on a support body of heat dissipating material;
- providing a flexible polymer dielectric tape including three parallel strips of conductive material with two outer strips disposed along opposite sides of the flexible tape and being continuous throughout a length embracing a plurality of cell units and a central strip that is discontinuous at each cell unit where said tape is apertured at spaced positions for receiving said cell units;
- providing interconnect tabs as part of each of said current carrying surfaces to said strips of conductive material;
- bonding said cell units to said interconnect tabs to connect together a plurality of cell units that are in the form of a string;
- said central strip forming a series connected group of cells and said outer strips forming a parallel connected group of cells;
- bonding each cell unit in the string to said support body;
- placing said support body at an approximate desired position on said housing base;
- and
- installing a radiant energy concentrator on said housing and adjusting the relative position between said concentrator and its related cell for proper optical alignment.
A process for manufacturing a solar cell module in a housing having a base, comprising:
- providing discrete photovoltaic cell units having opposed current carrying surfaces, said units comprising an upper cell of a first semiconductive material and a lower cell of a second semiconductive material mounted in optical alignment therewith, each cell has two current contact surfaces, and the cell units are mounted on a support body of heat dissipating material;
- providing a flexible polymer dielectric tape including at least two parallel strips of conductive material, said tape being apertured at spaced positions for receiving said cell units;
- providing interconnect tabs as part of each of said strips, said tabs being positioned to electrically connect said current contact surfaces to said strips of conductive material;
- bonding said interconnect tabs to current contact surfaces on said upper and lower cells to form cell units that are in the form of a string;
- bonding each cell unit in the string to said support body;
- placing said support body at an approximate desired position on said housing base;
- and
- installing a radiant energy concentrator on said housing and adjusting the relative position between said concentrator and its related cell for proper optical alignment.
A process for manufacturing a solar cell module having a plurality of concentrated sunlight tandem cell units, said process comprising:
- fabricating a plurality of upper photovoltaic cells;
- fabricating a plurality of lower photovoltaic cells;
- providing a support body which serves as a heat dissipator, said body having an electrically insulative surface for engagement with the lower of said cells;
- testing the individual cells;
- selecting matched cells for forming a tandem cell unit;
- bonding the upper cell and lower cell into a tandem cell unit together with said support body, said cells being in optical alignment with each other so that all radiation received by a lower cell passes through its associated upper cell;
- forming a flexible dielectric tape carrying a plurality of electrically conducting members that are secured to upper and lower surfaces of said upper and lower cells to form a string of electrically interconnected tandem cell units;
- cutting the flexible tape into unitary lengths of cell units;
- and
- installing cut lengths of said cell units onto a surface of a housing.
Dependencies are inferred from the claim text.