CN104009117B - Flexible thin film solar cell and preparing method thereof - Google Patents

Abstract

The invention discloses a method for preparing a flexible thin-film solar cell. The preparation method includes the steps of: forming a first transparent conductive layer on flexible glass fixed on a glass carrier, and forming a first opening on the first transparent conductive layer; Form an emitter thin film covering the first opening on the first transparent conductive layer, and form a second opening; form a second transparent conductive layer covering the second opening on the emitter thin film, and form the second transparent conductive layer and the emitter forming a third opening on the film; forming a first flexible adhesive layer on the second transparent conductive layer; forming a first flexible thin plate on the first flexible adhesive layer; encapsulating the above structure, and removing the glass carrier after encapsulation. Correspondingly, the invention also provides a flexible thin-film solar cell prepared by the method. Adopting the technical solution of the invention can effectively reduce the fragmentation rate in the preparation of flexible thin-film solar cells, improve production efficiency, and increase cell strength.

Description

A kind of flexible thin film solar cell and preparation method thereof

technical field

The invention belongs to the field of thin-film solar cell manufacture, and in particular relates to a flexible thin-film solar cell and a preparation method thereof.

Background technique

With the popularization of the concept of energy conservation and environmental protection and the rapid development of the photovoltaic field, the technology of generating electricity with solar cells has continued to advance, and the development of thin-film solar cells, especially flexible thin-film solar cells, has made significant progress. However, the substrates of existing flexible thin-film solar cells are mostly impermeable materials. During the preparation process, it is difficult to realize the structure of multiple cells connected in series on the same substrate, and only a single flexible cell structure can be made. In this way, in practical applications, it is necessary to connect individual batteries in series to increase the operating voltage of the battery application. This method increases the processing and preparation procedures of flexible solar cell application products to a large extent, and the complexity is high. In addition, flexible solar cells based on impermeable steel cannot achieve transparency.

At present, the industrialization technology of silicon-based thin-film batteries based on transparent glass is quite mature. It can be made into a battery assembly with multiple batteries connected in series, and these battery assemblies can be directly applied after being packaged. The preparation temperature is generally around 200°C, and the selected transparent glass is required to have no obvious absorption of specific laser light.

Transparent plastics are both transparent and flexible, and can be used as an alternative material for flexible transparent thin film battery substrates. However, plastics with high permeability, such as PET, PE and other plastics, are generally difficult to withstand a high temperature of 200 ° C, so it is difficult to apply to silicon-based thin-film batteries. And high-temperature-resistant plastics, such as PI, will obviously absorb laser light with a specific wavelength. For example, the absorption rate for a wavelength of 355nm can reach more than 85%. role.

Therefore, under the premise that there is no flexible material with high temperature resistance and high light transmittance, or there is no new effective insulation technology for the TCO conductive layer in the silicon-based thin film battery process, flexible and multi- Thin-film battery assemblies with cells in series present enormous challenges.

Contents of the invention

The invention provides a flexible thin-film solar cell in which multiple cells are connected in series on the same substrate.

According to one aspect of the present invention, a kind of preparation method of flexible thin-film solar cell is provided, and described preparation method comprises steps:

Step S101, fixing the flexible glass on a glass carrier with a thickness of 2-4 mm;

Step S102, forming a first transparent conductive layer on the flexible glass, and forming a first opening on the first transparent conductive layer;

Step S103, forming an emitter film on the first transparent conductive layer, the emitter film covering the first opening, and forming a second opening on the emitter film adjacent to the first opening;

Step S104, forming a second transparent conductive layer on the emitter film, the second transparent conductive layer covering the second opening, and forming a third transparent conductive layer on the second transparent conductive layer and the emitter film. open mouth

The third opening is adjacent to the second opening and away from the first opening;

Step S105, forming a first flexible adhesive layer on the second transparent conductive layer;

Step S106, forming a first flexible sheet on the first flexible adhesive layer;

Step S107, encapsulating the flexible glass, the first transparent conductive layer, the emitter thin film, the second transparent conductive layer, the first flexible adhesive layer and the first flexible thin plate, and removing the glass carrier after encapsulation.

According to a specific embodiment of the present invention, after the step S107, it also includes:

Step 108, sequentially forming a second flexible bonding layer and a second flexible thin plate on the other side of the flexible glass;

Step 109, packaging the flexible thin film solar cell.

According to another aspect of the present invention, a flexible thin-film solar cell is provided, and the flexible thin-film solar cell includes in order from bottom to top: flexible glass, a series connection composed of a first transparent conductive layer, an emitter thin film and a second transparent conductive layer A thin film battery, a first flexible adhesive layer and a first flexible thin plate; the flexible thin film solar battery is prepared by the preparation method provided by the present invention.

According to a specific embodiment of the present invention, the other side of the flexible glass relative to the tandem thin film battery includes in sequence: a second flexible adhesive layer and a second flexible thin plate.

The flexible glass with a thickness of 0.03-0.75mm used in the present invention has a relatively large amount of deformation, and can be curled within a certain range to show flexibility; at the same time, because the glass is transparent, the absorption of laser light is very small, and it can achieve the same effect as traditional conventional silicon. The effect of laser scribing insulation in thin-film battery technology.

Due to the small thickness of flexible glass, it has little mechanical strength and is fragile. In the battery preparation process, placing the flexible glass on a thick glass carrier can effectively avoid the breakage of the flexible glass, thereby meeting the requirements of mechanical transmission in the battery preparation process. After the battery structure is prepared on the flexible glass, the packaging of the thin-film battery can be completed through the bonding of the flexible adhesive layer and the flexible sheet material, and more importantly, its mechanical strength is significantly enhanced. After removing the thick glass carrier It can still meet the requirements of transfer, transportation and use of finished solar cells.

Description of drawings

Other characteristics, objects and advantages of the present invention will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

Figure 1 shows a schematic flow chart of a specific embodiment of a method for preparing a flexible thin-film solar cell according to the present invention;

FIG. 2 is a schematic flow diagram of another embodiment of a method for preparing a flexible thin-film solar cell according to the present invention;

3 to 12 are schematic structural views during the formation process of a flexible thin-film solar cell according to the present invention.

The same or similar reference numerals in the drawings represent the same or similar components.

detailed description

The following disclosure provides many different embodiments or examples for implementing different structures of the present invention. To simplify the disclosure of the present invention, components and arrangements of specific examples are described below. Furthermore, the present invention may repeat reference numerals and/or letters in different instances. This repetition is for the purpose of simplicity and clarity and does not in itself indicate a relationship between the various embodiments and/or arrangements discussed. It should be noted that components illustrated in the figures are not necessarily drawn to scale. Descriptions of well-known components and processing techniques and processes are omitted herein to avoid unnecessarily limiting the present invention.

Referring to FIG. 1 , FIG. 1 is a schematic flowchart of a specific embodiment of a method for preparing a flexible thin-film solar cell according to the present invention.

Step S101 , fixing the flexible glass 210 on the glass carrier 100 with a thickness of 2-4 mm, as shown in FIG. 3 . Preferably, the thickness of the flexible glass 210 is 0.03mm˜0.75mm, for example: 0.03mm, 0.1mm, 0.3mm or 0.75mm. Preferably, in order to increase the hardness of the prepared flexible thin-film solar cell, the flexible glass 210 is chemically toughened thin glass.

Referring to FIG. 4 and FIG. 5 , step S102 is performed to form a first transparent conductive layer 310 on the flexible glass 210 and form a first opening on the first transparent conductive layer 310 .

The first transparent conductive layer (Transparent Conductive Oxide, TCO) 310 can be formed by depositing a transparent oxide material using the Oerlikon thin film battery production system or the low temperature chemical vapor deposition (LPCVD) of Shanghai Ideal Energy Technology. Optionally, the material forming the first transparent conductive layer 310 includes: tin oxide, indium tin oxide, indium oxide, boron-doped zinc oxide, aluminum-doped zinc oxide and/or gallium-doped zinc oxide. Preferably, boron-doped zinc oxide (ZnO) is used to prepare the first transparent conductive layer 310 .

Preferably, the first opening is formed on the first transparent conductive layer 310 by laser ablation. Preferably, an ultraviolet laser with a wavelength of 355nm is used to form the first opening.

Step S103 , forming an emitter film 410 on the first transparent conductive layer 310 , the emitter film 410 covering the first opening, as shown in FIG. 6 .

Optionally, the emitter thin film 410 includes one or more of amorphous silicon, microcrystalline silicon, polycrystalline silicon and single crystal silicon thin films. The amorphous silicon, microcrystalline silicon, polycrystalline silicon or single crystal silicon film forms a single junction structure comprising a p-n junction, n-p junction, p-i-n junction or n-i-p junction, or forms a single junction structure comprising multiple p-n junctions, n-p junctions, p-i-n junctions or n-i-p junctions Knotted multi-knot structure.

Taking the emitter film 410 with a p-i-n structure formed of amorphous silicon (a-Si) as an example, it can be deposited by PECVD (Plasma Enhanced Chemical Vapor Deposition, plasma enhanced chemical vapor deposition) to deposit p-type, i-type, n-type Three layers of amorphous silicon are obtained. Preferably, if the light transmittance needs to be adjusted, the thickness of the i layer (intrinsic layer) can be adjusted to adjust the light transmittance.

Then referring to FIG. 7 , a second opening is formed on the emitter film 410 adjacent to the first opening. Preferably, the second opening is formed on the emitter film 410 by laser ablation. Preferably, a green laser with a wavelength of 532nm is used to form the second opening.

In step S104 , as shown in FIG. 8 , a second transparent conductive layer 320 is formed on the emitter film 410 , and the second transparent conductive layer 320 covers the second opening.

Optionally, the second transparent conductive layer 320 may be deposited by low temperature chemical vapor deposition (LPCVD).

Optionally, the material forming the second transparent conductive layer 320 includes: tin oxide, indium tin oxide, indium oxide, boron-doped zinc oxide, aluminum-doped zinc oxide and/or gallium-doped zinc oxide. The second transparent conductive layer 320 is preferably made of boron-doped zinc oxide (ZnO).

Referring to FIG. 9 , a third opening is formed on the second transparent conductive layer 320 and the emitter film 410 . It should be noted that the third opening is adjacent to the second opening and far away from the first opening. That is, the second opening is in the middle, and the first opening and the third opening are arranged on two sides of the second opening. The formation of the third opening enables the thin film solar cells to form a series structure.

Preferably, the third opening is formed on the second transparent conductive layer 320 and the emitter film 410 by laser ablation. Preferably, a green laser with a wavelength of 532nm is used to form the third opening.

After the third opening is formed, step S105 is continued, referring to FIG. 10 , laying the first flexible adhesive layer 510 on the second transparent conductive layer 320 . Optionally, the forming material of the first flexible adhesive layer 510 includes but not limited to: PVB (PolyVinyl Butyral), EVA (Ethylene-vinyl acetate copolymer) or transparent silicone resin film.

Step S106 , laying a first flexible sheet 610 on the first flexible bonding layer 510 . Optionally, the forming material of the first flexible thin plate 610 includes, but is not limited to: silica gel, resin, polyethylene, fluorine-containing film, and flat light-transmitting plastic film material with a suede structure.

Step S107 , laminating and encapsulating the flexible glass 210 , the first transparent conductive layer 310 , the emitter film 410 , the second transparent conductive layer 320 , the first flexible bonding layer 510 and the first flexible thin plate 610 . The glass carrier 100 is removed after encapsulation, as shown in FIG. 11 . After encapsulation, the desired flexible thin film solar cell is formed. Since each required layer has been formed on the flexible glass 210, the strength of the flexible thin film solar cell will not be affected after the glass carrier 100 is removed.

Although the mechanical strength of the flexible thin-film solar cell has met the requirements of application, loading, transportation, etc., in order to make the mechanical strength of the thin-film solar cell stronger and further reduce the fragmentation rate, preferably, referring to FIG. 2, in the Also include after step S107:

Step 108 , forming a second flexible adhesive layer 520 and a second flexible thin plate 530 on the flexible glass 210 in sequence. As shown in FIG. 12 , the second flexible bonding layer 520 and the second flexible sheet 530 are formed on the flexible glass 210 on the other side of the first transparent conductive layer 310 and other layers.

Optionally, the forming material of the second flexible adhesive layer 520 includes but not limited to: PVB (PolyVinylButyral), EVA (ethylene-vinyl acetate copolymer) or transparent silicone resin film.

Optionally, the forming material of the second flexible thin plate 620 includes, but is not limited to: silica gel, resin, polyethylene, fluorine-containing film, and flat light-transmitting plastic film material with a suede structure.

Step 109, laminating and encapsulating the flexible thin film solar cell. Preferably, lamination is used for encapsulation, and a solar cell module laminator is used for lamination encapsulation to complete the production of flexible thin film batteries. The flexible solar cell provided by the above manufacturing method has a simple structure, is easy to realize, and has a prospect of large-scale application.

The present invention also provides a flexible thin-film solar cell prepared by the above-mentioned method provided by the present invention. The flexible thin-film solar cell includes, from bottom to top, flexible glass 210, a series thin-film cell composed of a first transparent conductive layer 310, an emitter film 410 and a second transparent conductive layer 320, a first flexible adhesive layer 510 and a first transparent conductive layer. Flexible sheet 520 .

Preferably, in order to increase the mechanical strength of the flexible thin-film solar cell and further reduce the fragmentation rate, the flexible glass 210 further includes: a second flexible adhesive layer 520 and a second The flexible thin plate 620 is double-sided encapsulation of the flexible thin film solar cell.

Optionally, the emitter thin film 410 includes one or more of amorphous silicon, microcrystalline silicon, polycrystalline silicon and single crystal silicon thin films. The amorphous silicon, microcrystalline silicon, polycrystalline silicon or single crystal silicon film forms a single junction structure comprising a p-n junction, n-p junction, p-i-n junction or n-i-p junction, or forms a single junction structure comprising multiple p-n junctions, n-p junctions, p-i-n junctions or n-i-p junctions Knotted multi-knot structure.

Preferably, the thickness of the flexible glass is 0.03mm-0.75mm, for example: 0.03mm, 0.05mm, 0.1mm, 0.3mm or 0.75mm.

Since the flexible thin-film solar cell claimed in the present invention is prepared by using the method for preparing the flexible thin-film solar cell disclosed in the present invention, reference can be made to the relevant description of the application text for the materials and other features used in the structure of the flexible thin-film solar cell , which will not be repeated here.

Since the thickness of the flexible glass used as the substrate of the flexible thin-film solar cell in the present invention is small, it has low mechanical strength and is fragile. In the present invention, the solar cell is placed on a thick glass carrier during the preparation process, which effectively avoids the breakage of the flexible glass 210 substrate, thereby meeting the mechanical transmission requirements of the glass substrate during the cell preparation process. After the battery structure is made on the flexible glass, through the bonding of the flexible adhesive layer and the flexible sheet material, not only the packaging of the thin film battery can be completed, but also its mechanical strength can be significantly enhanced, which meets the needs of the transfer, transportation and transportation of the finished solar cell. use requirements.

Although the example embodiments and their advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made to these embodiments without departing from the spirit and scope of the invention as defined by the appended claims. For other examples, those of ordinary skill in the art will readily understand that the order of process steps may be varied while remaining within the scope of the present invention.

In addition, the scope of application of the present invention is not limited to the process, mechanism, manufacture, material composition, means, methods and steps of the specific embodiments described in the specification. From the disclosure of the present invention, those of ordinary skill in the art will easily understand that for the processes, mechanisms, manufacturing, material compositions, means, methods or steps that currently exist or will be developed in the future, they are implemented in accordance with the present invention Corresponding embodiments described which function substantially the same or achieve substantially the same results may be applied in accordance with the present invention. Therefore, the appended claims of the present invention are intended to include these processes, mechanisms, manufacture, material compositions, means, methods or steps within their protection scope.

Claims (10)

1. a kind of preparation method of flexible thin-film solar cell is it is characterised in that described preparation method includes step:

A) flexible glass being fixed on thickness is on the glass carrier of 2～4mm；

B) form the first transparency conducting layer in described flexible glass, and form first on described first transparency conducting layer and open Mouthful；

C) transmitting very thin films are formed on described first transparency conducting layer, described transmitting very thin films cover described first opening, and Tighten adjacent described first opening in described transmitting very thin films and form the second opening；

D) second transparency conducting layer is formed on described transmitting very thin films, described second transparency conducting layer covers described second and opens Mouthful, and the 3rd opening is formed on described second transparency conducting layer and described transmitting very thin films；

Described 3rd opening is close to described second opening, and away from described first opening；

E) first flexible adhesion layer is formed on described second transparency conducting layer, described first flexible adhesion layer covers the described 3rd Opening；

F) form the first flexible thin on described first flexible adhesion layer；

G) to described flexible glass, the first transparency conducting layer, transmitting very thin films, the second transparency conducting layer, the first flexible adhesion layer It is packaged with the first flexible thin, remove described glass carrier after packaging.

2. preparation method according to claim 1 is it is characterised in that further comprise the steps of: after described step g)

H) another side in described flexible glass sequentially forms the second flexible adhesion layer and the second flexible thin；

I) described flexible thin-film solar cell is packaged.

3. preparation method according to claim 1 and 2 it is characterised in that described flexible glass thickness be 0.03mm～ 0.75mm.

4. preparation method according to claim 3 is opened it is characterised in that being formed described first by the way of laser burn Mouth, described second opening and described 3rd opening.

5. preparation method according to claim 4 is it is characterised in that the laser for 355nm forms described using wavelength One opening；Described second opening and described 3rd opening are formed using the laser for 532nm for the wavelength.

6. preparation method according to claim 1 and 2 is it is characterised in that described transmitting very thin films include non-crystalline silicon, crystallite One or more of silicon, polysilicon and monocrystalline silicon thin film；

Described non-crystalline silicon, microcrystal silicon, polysilicon or monocrystalline silicon thin film form and comprise a p-n junction, n-p junction, p-i-n junction or n- The single-junction structure of i-p knot, or form the multijunction structure comprising that multiple p-n junctions, n-p junction, p-i-n junction or n-i-p tie.

7. a kind of flexible thin-film solar cell, described flexible thin-film solar cell includes from the bottom to top successively: flexible glass, By the first transparency conducting layer, transmitting very thin films and the second transparency conducting layer form tandem thin-film battery, the first flexible adhesion layer With the first flexible thin；

It is characterized in that,

Described flexible thin-film solar cell adopts any one preparation method preparation in claim 1～6.

8. flexible thin-film solar cell according to claim 7 is it is characterised in that in described flexible glass with respect to institute The opposite side stating tandem thin-film battery includes successively: the second flexible adhesion layer and the second flexible thin.

9. the flexible thin-film solar cell according to claim 7 or 8 is it is characterised in that described transmitting very thin films include One or more of non-crystalline silicon, microcrystal silicon, polysilicon and monocrystalline silicon thin film；

Described non-crystalline silicon, microcrystal silicon, polysilicon or monocrystalline silicon thin film form and comprise a p-n junction, n-p junction, p-i-n junction or n- The single-junction structure of i-p knot, or form the multijunction structure comprising that multiple p-n junctions, n-p junction, p-i-n junction or n-i-p tie.

10. the flexible thin-film solar cell according to claim 7 or 8 is it is characterised in that the thickness of described flexible glass For 0.03mm～0.75mm.