High altitude aircraft with integrated solar cells, and associated systems and methods

Patent metadata

Field	Value
Publication number	US-2016194072-A1
Application number	US-201414310415-A
Country	US
Kind code	A1
Filing date	Jun 20, 2014
Priority date	Jul 10, 2013
Publication date	Jul 7, 2016
Grant date	—

Abstract

A method of making a solar cell assembly includes placing backsides of multiple solar cells in contact with a substrate. The solar cells are electrically connected to each other. Heat and pressure are applied to the solar cells and the substrate to simultaneously impress the solar cells into the substrate and bond the solar cells to the substrate.

First claim

What is claimed is:

1 . A method of making a solar cell assembly, comprising:
placing backsides of multiple solar cells in contact with a substrate; electrically connecting the solar cells to each other; and applying heat and pressure to the solar cells and the substrate to simultaneously impress the solar cells into the substrate and bond the solar cells to the substrate.

2 . The method of claim 1 , wherein applying the heat and pressure to the solar cells and the substrate causes the solar cells to form recesses into the substrate that are simultaneously filled by the solar cells.

3 . The method of claim 2 , further comprising:
stacking the multiple solar cells and the substrate on a mold surface, the mold surface having a profile that produces a curved surface of a wing or a stabilizer of an aircraft, wherein the heat and pressure is applied while the solar cells and the substrate are stacked on the mold surface.

4 . The method of claim 2 , further comprising:
applying adhesive between the backsides of the solar cells and the substrate, wherein the heat and the pressure applied to the solar cells and the substrate causes the adhesive to form bonds between the backsides of the solar cells and bottoms of the recesses.

5 . The method of claim 4 , wherein the heat and the pressure applied to the solar cells and the substrate causes the adhesive to form bonds between side edges of the solar cells and side walls of the recesses such that the substrate and the solar cells form an intimately integrated assembly that can transmit compressive loads from one solar cell to another via surrounding portions of the substrate along a load path.

6 . The method of claim 2 , wherein applying the heat and the pressure to the solar cells and the substrate also causes inter-cell recesses in the substrate between one or more of the solar cells, the method further comprising:
filling, at least partially, the inter-cell recesses with a filler material.

7 . The method of claim 1 , wherein the substrate comprises a composite structure including:
first and second fabric layers coated in adhesive; and a center core layer disposed between the first and second fabric layers, wherein the adhesive is cured when applying the heat and the pressure.

8 . The method of claim 7 , wherein the solar cells are impressed into at least the first fabric layer of the substrate while applying the heat and the pressure.

9 . The method of claim 8 , wherein the solar cells are impressed into both the first fabric layer and the center core layer of the substrate while applying the heat and the pressure.

10 . The method of claim 1 , further comprising:
providing a protective layer having an inside surface; coating the inside surface of the protective layer with a protective layer adhesive to bond the inside surface of the protective layer to active surfaces of the solar cells and portions of the substrate, wherein the protective layer is transparent to wavelengths that activate a current generation function of the solar cells.

11 . The method of claim 10 , wherein the solar cells comprise bare crystalline solar cells that are in intimate contact with the protective layer and the substrate.

12 . A method for making solar powered aircraft, comprising:
placing multiple bare solar cells on a transparent film bearing a first adhesive with active surfaces of the solar cells against the first adhesive and backside surfaces of the bare solar cells facing away from the transparent film; electrically connecting the bare solar cells; disposing a second adhesive against the backside surfaces of the bare solar cells; placing a substrate including one or more layers of fabric and a core against the first and second adhesives; drawing a vacuum on a region including the bare solar cells, the transparent film, and the substrate; and forming a wing surface or a stabilizer surface by heating the region to simultaneously cure the first and second adhesives and form a cohesive bond between the substrate, the bare solar cells and the transparent film.

13 . The method of claim 12 , wherein drawing the vacuum causes the bare solar cells to recess into the substrate.

14 . The method of claim 13 , wherein drawing the vacuum on the region includes drawing the vacuum over a mold surface having a profile of the wing surface or the stabilizer surface.

15 . A solar powered aircraft, comprising:
a substrate having a curvature to form a lift surface; a plurality of solar cells carried by, bonded to, and impressed into the substrate; and electrical connections between the solar cells carried by the substrate, the electrical connections coupled to link the solar cells together to power the solar powered aircraft while in flight.

16 . The solar powered aircraft of claim 15 , wherein the solar cells are disposed, at least partially, within recesses impressed into the substrate.

17 . The solar powered aircraft of claim 16 , wherein the solar cells are bonded along backsides of the solar cells to bottom surfaces of the recesses and along side edges of the solar cells to side walls of the recesses with one or more adhesives to form an intimately integrated assembly that transmits compressive loads from one solar cell to another via surrounding portions of the substrate along one or more load paths.

18 . The solar powered aircraft of claim 17 , wherein the substrate is a multi-layer substrate and wherein the solar cells are impressed into at least one layer of the multi-layer substrate.

19 . The solar powered aircraft of claim 18 , wherein the solar cells are impressed into two layers of the multi-layer substrate.

20 . The solar powered aircraft of claim 19 , wherein the substrate comprises:
first and second fabric layers coated in adhesive material; and a core layer disposed between the first and second fabric layers, wherein the adhesive material is cured when applying the heat and the pressure to the solar cells and the substrate to simultaneously bond and shape the solar cells and the substrate into the lift surface of the solar powered aircraft.

21 . The solar powered aircraft of claim 17 , further comprising:
a protective layer disposed over active surfaces of the solar cells and the substrate with an additional adhesive, wherein the protective layer is transparent to wavelengths that activate a current generation function of the solar cells.

22 . The solar powered aircraft of claim 21 , wherein the solar cells are crystalline solar cells that are in intimate contact with the protective layer and the substrate without intervening solar cell packages surrounding the solar cells.

Assignees

• Google Inc

Inventors

• Cornew Daniel H
• Yaney Maximus

Classifications

• Y02E10/50

  Photovoltaic [PV] energy · CPC title

• H02S10/40

  Mobile PV generator systems · CPC title

• B64C3/32 Primary

  specially adapted for mounting power plant · CPC title

• B64U50/31

  generated by photovoltaics · CPC title

• H02S20/30 Primary

  Supporting structures being movable or adjustable, e.g. for angle adjustment · CPC title