Flexible gallium arsenide solar cell module and preparation method thereof

Abstract

The invention discloses a flexible gallium arsenide solar cell module and a preparation method thereof. The solar cell module comprises a plurality of flexible gallium arsenide solar cell monomers, an interconnection sheet, a parallel bus bar, a cover sheet adhesive layer and a transparent polyimide film, the metal positive electrode and the metal negative electrode of each flexible gallium arsenide solar cell monomer are located on the front face of the flexible gallium arsenide solar cell monomer, and the multiple flexible gallium arsenide solar cell monomers are arranged and connected through interconnection pieces to form a flexible gallium arsenide solar cell piece. A metal positive electrode and a metal negative electrode of the flexible gallium arsenide solar cell are respectively connected with the parallel bus bar through an interconnection sheet, and a cover sheet adhesive layer and a transparent polyimide film are sequentially arranged on the front surface of the flexible gallium arsenide solar cell; the positive electrode on the back surface of the battery is led to the front surface of the battery, so that the positive electrode and the negative electrode of the battery are arranged on the front surface of the battery, single lead-out and serial interconnection sheet welding are directly and synchronously carried out on the front surface, and welding operation procedures are reduced.

Description

Technical Field

[0001] This invention relates to the technical field of flexible gallium arsenide solar cells, and in particular to a flexible gallium arsenide solar cell module and its preparation method. Background Technology

[0002] The traditional method for manufacturing gallium arsenide (GaAs) solar cell modules involves welding interconnects to the positive electrode of each cell, applying a cover adhesive, covering it with a glass cover, curing it to form a single CIC cell, and then connecting the CIC solar cells in series and parallel by welding the interconnects on the back to form a module. This method has the following disadvantages: 1. The glass cover is prone to cracking if the bending diameter is too small, and chipping or breakage is likely during production; 2. Before manufacturing the module, each cell needs to be individually coated with adhesive and covered to form a CIC cell, and then connected in series and parallel by welding on the back to form the module. This requires multiple production steps and a long processing time. Summary of the Invention

[0003] The purpose of this invention is to address the shortcomings of existing technologies by providing a flexible gallium arsenide solar cell module and its fabrication method. The positive electrode on the back of the cell is brought to the front of the cell, so that both the positive and negative electrodes are on the front of the cell. The interconnecting sheets of individual leads and series connections are directly and simultaneously welded on the front, reducing the number of welding operations.

[0004] To achieve the above objectives, the technical solution provided by the present invention is as follows: a flexible gallium arsenide solar cell module, comprising a plurality of flexible gallium arsenide solar cell units, interconnecting sheets, parallel busbars, a cover film adhesive layer, and a transparent polyimide film; the metal positive electrode and metal negative electrode of each flexible gallium arsenide solar cell unit are located on the front side of the flexible gallium arsenide solar cell unit, and the plurality of flexible gallium arsenide solar cell units are arranged in a stacked manner and connected by interconnecting sheets to form a flexible gallium arsenide solar cell sheet; the metal positive electrode and metal negative electrode of the flexible gallium arsenide solar cell sheet are respectively connected to the parallel busbars through interconnecting sheets, and the front side of the flexible gallium arsenide solar cell sheet is sequentially provided with a cover film adhesive layer and a transparent polyimide film.

[0005] Furthermore, the flexible gallium arsenide solar cell includes a metal anode, an epitaxial material layer, a back electrode metal layer, an electrode metal thickening layer, and a metal cathode; the metal anode, epitaxial material layer, back electrode metal layer, and electrode metal thickening layer are stacked sequentially from top to bottom, and the metal cathode is disposed above the electrode metal thickening layer and located on one side of the metal anode, epitaxial material layer, and back electrode metal layer.

[0006] Furthermore, the metal anode of the flexible gallium arsenide solar cell is connected to the metal cathode of another flexible gallium arsenide solar cell via an interconnect.

[0007] Furthermore, the flexible gallium arsenide solar cell includes an anti-reflection film, which is disposed on the exposed surfaces of the metal anode, the epitaxial material layer, and the back electrode metal layer.

[0008] A method for fabricating a flexible gallium arsenide solar cell module according to the above-described method includes the following steps: S1. Select a base substrate and epitaxially grow a sacrificial layer and a battery material layer on the base substrate in sequence; S2. A back electrode metal layer is disposed on the side of the battery material layer away from the base substrate; S3. Thicken the electrode metal layer by electroplating or chemical plating; S4. Perform a substrate stripping process. By selectively etching the sacrificial layer, separate the base substrate and the battery material layer. Remove the back protective material by solution cleaning to obtain an epitaxial material layer with a metal substrate. S5. Temporarily bond the epitaxial material layer to the transparent rigid substrate, and clean the sample surface by ultrasonic cleaning with acetone, isopropanol and hydrochloric acid solutions in sequence to remove organic matter, metal particles and oxide impurities from the sample surface. S6. Perform photolithography on the surface of the epitaxial material layer to pattern the etching process, etching down to the electrode metal thickening layer to form the front positive electrode area, and then clean and remove the photoresist. S7. Spin-coat photoresist onto the surface, expose and develop it to form the front electrode pattern, and then deposit metal to create the gate lines, metal negative electrode and metal positive electrode. Use photoresist remover and pure water to remove the photoresist and rinse the surface clean. S8. Deposit an anti-reflective film on the surface except for the metal negative electrode and the metal positive electrode by vapor deposition; S9. Laser cutting is used to cut out each battery unit, thus obtaining the required flexible gallium arsenide solar cell. S10. Arrange the flexible gallium arsenide solar cell cells according to the number of series connections, place interconnecting plates on the corresponding electrodes and perform resistance welding, and connect the cells and parallel busbars in series and parallel through the interconnecting plates to form a module semi-finished product. S11. The front of the entire battery of the component semi-finished product is coated with a cover adhesive layer in a graphic manner using a tool, and then covered with a transparent polyimide film. S12. The semi-finished module is pressurized to spread the cover sheet across the entire surface of the battery, controlling the consistency of the overall thickness, and vacuuming is used to remove air bubbles from the cover sheet adhesive. S13. The semi-finished module is heated to 40℃-120℃ for 20min-60min to cure the cover adhesive. After curing, it is prepared into a flexible gallium arsenide solar cell module.

[0009] Furthermore, step S1 includes: the sacrificial layer material is AlAs or InAlP.

[0010] Furthermore, step S1 includes: the battery material layer is one or more of GaAs, GaInP, InGaAs, AlGaAs, and AlGaInP materials.

[0011] Furthermore, step S2 includes: depositing a back electrode metal layer on the side of the metal material layer away from the base substrate by means of evaporation or sputtering, wherein the metal material layer is a combination of Cu, Au, Pt, Ag, Ni and Cr materials.

[0012] Furthermore, step S3 includes: the thickness of the electrode metal thickening layer is in the range of 15-50 μm.

[0013] Furthermore, step S8 includes: the material of the antireflective coating is at least two of TiO2, Al2O3, SiO2, ZnS, and MgF2.

[0014] Compared with the prior art, the present invention has the following advantages and beneficial effects: Compared with existing technologies, this invention simplifies the fabrication process of flexible gallium arsenide (GaAs) solar cell modules. It eliminates the need for individual cell fabrication before module assembly, reducing the fabrication steps. Furthermore, single-sided welding is more convenient and efficient than double-sided welding. Simultaneously, this invention employs a novel encapsulation method, avoiding cell defects such as glass cover chipping and breakage, thus reducing the cell defect rate and the probability of module rework and cell replacement. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of a flexible gallium arsenide solar cell module. Detailed Implementation

[0016] The present invention will be further described below with reference to specific embodiments.

[0017] See Figure 1 As shown, the flexible gallium arsenide solar cell module provided in this embodiment includes several flexible gallium arsenide solar cell cells, interconnecting sheets 7, parallel busbars 8, cover adhesive layer 9, and transparent polyimide film 10.

[0018] A flexible gallium arsenide solar cell includes a metal anode 1, an epitaxial material layer 2, a back electrode metal layer 3, an electrode metal thickening layer 4, an anti-reflection film 5, and a metal cathode 6. The metal anode 1, epitaxial material layer 2, back electrode metal layer 3, and electrode metal thickening layer 4 are stacked sequentially from top to bottom. The metal cathode 6 is disposed above the electrode metal thickening layer 4 and on one side of the metal anode 1, epitaxial material layer 2, and back electrode metal layer 3. The anti-reflection film 5 is disposed on the exposed surface of the metal anode 1, epitaxial material layer 2, and back electrode metal layer 3. The metal positive electrode 6 and metal negative electrode 1 of each flexible gallium arsenide solar cell are located on the front side of the flexible gallium arsenide solar cell. Several flexible gallium arsenide solar cell cells are arranged in a stack. The metal negative electrode 1 of one flexible gallium arsenide solar cell cell and the metal positive electrode 6 of another flexible gallium arsenide solar cell cell are connected by an interconnecting plate 7 to form a flexible gallium arsenide solar cell sheet. The metal positive electrode 6 and metal negative electrode 1 of the flexible gallium arsenide solar cell sheet are connected to a parallel bus bar 8 by the interconnecting plate 7, respectively. The front side of the flexible gallium arsenide solar cell sheet is sequentially provided with a cover film adhesive layer 9 and a transparent polyimide film 10.

[0019] A method for fabricating a flexible gallium arsenide solar cell module according to the above-described method includes the following steps: S1. Select a base substrate and sequentially epitaxially grow a sacrificial layer and a battery material layer on the base substrate; the sacrificial layer material is AlAs or InAlP. The battery material layer is one or more of GaAs, GaInP, InGaAs, AlGaAs, and AlGaInP materials.

[0020] S2. A back electrode metal layer 3 is formed on the side of the metal material layer away from the base substrate by means of evaporation or sputtering. The metal material layer is a combination of Cu, Au, Pt, Ag, Ni and Cr materials.

[0021] S3. Metal deposition is performed by electroplating or chemical plating to form an electrode metal thickening layer 4; the thickness of the electrode metal thickening layer 4 is in the range of 15-50um, and the material can be a metal such as copper or silver.

[0022] S4. Perform a substrate stripping process. By selectively etching the sacrificial layer, separate the base substrate and the battery material layer. Remove the back protective material by cleaning with solutions such as acetone, toluene, and NMP, thereby obtaining the epitaxial material layer 2 with the metal substrate.

[0023] S5. Temporarily bond the epitaxial material layer 2 to the transparent rigid substrate, and clean the sample surface by sequentially using acetone, isopropanol and hydrochloric acid solution for ultrasonic cleaning to remove organic matter, metal particles and oxide impurities from the sample surface.

[0024] S6. Perform photolithography on the surface of epitaxial material layer 2 to pattern the etching down to the electrode metal thickening layer 4 to form the positive electrode area on the front side. Then clean and remove the photoresist.

[0025] S7. Spin-coat photoresist onto the surface, expose and develop it to form the front electrode pattern, and then deposit metal to create the gate lines, metal anode 1 and metal cathode 6. Use photoresist remover and pure water to remove the photoresist and rinse the surface clean.

[0026] S8. An antireflective film 5 is deposited on the surface of the metal anode 1 and the metal cathode 6 by vapor deposition; the material of the antireflective film 5 is at least two of TiO2, Al2O3, SiO2, ZnS, and MgF2.

[0027] S9. Laser cutting is used to cut out each battery unit, thus obtaining the required flexible gallium arsenide solar cell.

[0028] S10. Arrange the flexible gallium arsenide solar cell cells in series according to the number of cells connected in series. Place the interconnecting sheet 7 on the corresponding electrode and perform resistance welding. Connect the cell cells and parallel busbars 8 in series and parallel through the interconnecting sheet 7 to form a semi-finished module.

[0029] S11. The front of the overall battery of the component semi-finished product is coated with a cover film adhesive layer 9 using a tool, and then covered with a transparent polyimide film 10.

[0030] S12. The semi-finished module is pressurized to spread the cover sheet across the entire surface of the battery, controlling the consistency of the overall thickness, and vacuuming is used to remove air bubbles from the cover sheet adhesive.

[0031] S13. The semi-finished module is heated to 40℃-120℃ for 20min-60min to cure the cover adhesive. After curing, it is prepared into a flexible gallium arsenide solar cell module.

[0032] The above-described embodiments are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Therefore, any changes made in accordance with the shape and principle of the present invention should be covered within the protection scope of the present invention.

Claims

1. A flexible gallium arsenide solar cell module, characterized in that: The solar cell comprises several flexible gallium arsenide (GaAs) solar cells, interconnecting sheets, parallel busbars, a cover film, and a transparent polyimide film. The positive and negative metal electrodes of each flexible GaAs solar cell are located on the front side of the cell. Several flexible GaAs solar cells are arranged in a stacked manner and connected by interconnecting sheets to form a flexible GaAs solar cell sheet. The positive and negative metal electrodes of the flexible GaAs solar cell sheet are connected to the parallel busbars via interconnecting sheets. A cover film and a transparent polyimide film are sequentially disposed on the front side of the flexible GaAs solar cell sheet.

2. The flexible gallium arsenide solar cell module according to claim 1, characterized in that: The flexible gallium arsenide solar cell includes a metal anode, an epitaxial material layer, a back electrode metal layer, an electrode metal thickening layer, and a metal cathode; the metal anode, epitaxial material layer, back electrode metal layer, and electrode metal thickening layer are stacked sequentially from top to bottom, and the metal cathode is disposed above the electrode metal thickening layer and located on one side of the metal anode, epitaxial material layer, and back electrode metal layer.

3. A flexible gallium arsenide solar cell module according to claim 2, characterized in that: The metal anode of one flexible gallium arsenide solar cell is connected to the metal cathode of another flexible gallium arsenide solar cell via an interconnect.

4. A flexible gallium arsenide solar cell module according to claim 3, characterized in that: The flexible gallium arsenide solar cell includes an anti-reflection film, which is disposed on the exposed surfaces of the metal anode, the epitaxial material layer, and the back electrode metal layer.

5. A method for fabricating a flexible gallium arsenide solar cell module according to any one of claims 1-4, characterized in that, Includes the following steps: S1. Select a base substrate and epitaxially grow a sacrificial layer and a battery material layer on the base substrate in sequence; S2. A back electrode metal layer is disposed on the side of the battery material layer away from the base substrate; S3. Thicken the electrode metal layer by electroplating or chemical plating; S4. Perform a substrate stripping process. By selectively etching the sacrificial layer, separate the base substrate and the battery material layer. Remove the back protective material by solution cleaning to obtain an epitaxial material layer with a metal substrate. S5. Temporarily bond the epitaxial material layer to the transparent rigid substrate, and clean the sample surface by ultrasonic cleaning with acetone, isopropanol and hydrochloric acid solutions in sequence to remove organic matter, metal particles and oxide impurities from the sample surface. S6. Perform photolithography on the surface of the epitaxial material layer to pattern the etching process, etching down to the electrode metal thickening layer to form the front positive electrode area, and then clean and remove the photoresist. S7. Spin-coat photoresist onto the surface, expose and develop it to form the front electrode pattern, and then deposit metal to create the gate lines, metal negative electrode and metal positive electrode. Use photoresist remover and pure water to remove the photoresist and rinse the surface clean. S8. Deposit an anti-reflective film on the surface except for the metal negative electrode and the metal positive electrode by vapor deposition; S9. Laser cutting is used to cut out each battery unit, thus obtaining the required flexible gallium arsenide solar cell. S10. Arrange the flexible gallium arsenide solar cell cells according to the number of series connections, place interconnecting plates on the corresponding electrodes and perform resistance welding, and connect the cells and parallel busbars in series and parallel through the interconnecting plates to form a module semi-finished product. S11. The front of the entire battery of the component semi-finished product is coated with a cover adhesive layer in a graphic manner using a tool, and then covered with a transparent polyimide film. S12. The semi-finished module is pressurized to spread the cover sheet across the entire surface of the battery, controlling the consistency of the overall thickness, and vacuuming is used to remove air bubbles from the cover sheet adhesive. S13. The semi-finished module is heated to 40℃-120℃ for 20min-60min to cure the cover adhesive. After curing, it is prepared into a flexible gallium arsenide solar cell module.

6. The method for preparing a flexible gallium arsenide solar cell module according to claim 5, characterized in that, Step S1 includes: the sacrificial layer material is AlAs or InAlP.

7. The method for fabricating a flexible gallium arsenide solar cell module according to claim 5, characterized in that, Step S1 includes: the battery material layer is one or more of GaAs, GaInP, InGaAs, AlGaAs, and AlGaInP materials.

8. The method for preparing a flexible gallium arsenide solar cell module according to claim 5, characterized in that, Step S2 includes: depositing a back electrode metal layer on the side of the metal material layer away from the base substrate by means of evaporation or sputtering, wherein the metal material layer is a combination of Cu, Au, Pt, Ag, Ni and Cr materials.

9. The method for preparing a flexible gallium arsenide solar cell module according to claim 5, characterized in that, Step S3 includes: the thickness of the electrode metal thickening layer is in the range of 15-50 μm.

10. The method for preparing a flexible gallium arsenide solar cell module according to claim 5, characterized in that, Step S8 includes: the material of the antireflective coating is at least two of TiO2, Al2O3, SiO2, ZnS, and MgF2.

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