CN109427925A - A kind of compound encapsulation structure and its packaging method of component - Google Patents

Abstract

The invention discloses a composite packaging structure of a component and a packaging method thereof. The composite packaging structure is composed of a panel, a first packaging adhesive film, a battery sheet, a second packaging adhesive film and a back plate in order to form a laminate. The busbar can be connected to the junction box through the through holes on the backplane; the assembly is formed by placing the laminates in the package structure above in a laminator, vacuuming and heating at a low temperature, and then bonding the package laminates to form The laminate is taken out after cooling, and finally the busbars of the laminate are drawn out and connected to the junction box through the through holes on the backplane to obtain a photovoltaic module. The invention combines the advantages of EVA and POE materials. The transparent EVA film is layered directly on the battery string to achieve good optical absorption in the short wavelength range of the solar cell response. The safety of operation in high humidity environment and long-term aging resistance enable the components to be used for a long time.

Description

Composite packaging structure of a component and packaging method thereof

technical field

The invention relates to the technical field of photovoltaic modules, in particular to a composite packaging structure of a module and a packaging method thereof, which are especially suitable for sealing black silicon cell sheets with good optical absorption in short wavelength bands.

Background technique

The solar cell module is a key step in the production of solar cells. The encapsulation of the cell can not only ensure the life of the cell, but also enhance the strength of the cell. The high quality and long life of the product are the keys to winning customer satisfaction, so the packaging quality of the component board is very important. The commonly used packaging process of solar cell modules is: battery inspection → front welding → back serial connection → laying → lamination → welding junction box → component testing → appearance inspection → packaging and storage. Among them, laying mainly refers to the lamination of glass, EVA, battery, and backplane. At present, the encapsulation films used for laying and laminating double-glass modules mainly include EVA film and POE film. EVA film is an ethylene-vinyl acetate copolymer with low melting point, good fluidity, high transparency, and lamination process. Mature and other advantages, it is currently the main packaging material for double-glass modules. However, due to the low strength of EVA film, high water vapor transmission rate and water absorption rate, and poor weather resistance, edge sealing is required for double-glass modules. However, there will still be water vapor transmission during normal use, resulting in The film is atomized, which affects the light transmittance and reduces the power generation of the module. POE is an ethylene-octene copolymer. Compared with EVA film, the biggest advantage of POE film is low water vapor transmission rate and high volume resistivity, which ensures the safety and reliability of the module in high temperature and high humidity environment. Long-term aging resistance, so that the components can be used for a long time. Therefore, it is difficult to use a single photovoltaic module encapsulation film to take into account the advantages of high transparency, good optical absorption in the short wavelength band, and low water absorption, high insulation, and strong weather resistance.

For black silicon solar cells prepared by reactive ion dry etching (RIE), the characteristics of the cells are that the short-wave end response is better than that of conventional cells, so that more sunlight can be captured and the photoelectric conversion efficiency of the cells can be improved. . If it is simply encapsulated with POE material, it is limited by its poor short-wave light transmittance and large encapsulation power loss, which cannot reflect the advantages of this type of cell.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a composite packaging structure of a component and a packaging method thereof in view of the above technical problems existing in the prior art.

The present invention is achieved through the following technical solutions:

A composite packaging structure of a component, comprising a panel, a first packaging film, a battery sheet, a second packaging film and a backplane, the panel, the first packaging film, the battery sheet, the second packaging film and the backplane The photovoltaic modules are prepared by stacking in sequence to form a stack, the cell pieces are provided with busbars, and the busbars are drawn out and connected to the junction box through the through holes on the backplane.

Further, the panel is made of high light transmission glass, which must have high light transmission for wavelengths in the range of 350nm to 1200nm.

Further, the first encapsulation film is a composite material of transparent EVA (ethylene-vinyl acetate copolymer) and POE (ethylene-octene copolymer).

Further, the battery pieces are connected into battery strings via welding ribbons, the distance between the battery pieces is 2.5mm-4.5mm, the battery strings are arranged in parallel with the battery strings, and the distance between the battery strings is 2.5mm-4.5mm.

Further, the second encapsulation film is a white EVA (ethylene-vinyl acetate copolymer) and POE (ethylene-octene copolymer) composite material.

Further, the back plate is a glass or resin flat plate.

The packaging method of a component as described above, comprising the following steps:

(1) Laminate the panel, the first encapsulation film, the battery sheet, the second encapsulation film and the backplane in sequence to form a laminate, and the battery sheet is provided with a busbar;

A. The panel is made of high light transmission glass, which must have high light transmission for wavelengths in the range of 350nm to 1200nm;

B. The first encapsulating film is a composite material of transparent EVA (ethylene-vinyl acetate copolymer) and POE (ethylene-octene copolymer), and a transparent EVA film (ethylene-vinylidene - Vinyl acetate copolymer), 10-50mm from the edge of the module, and the packaging part that does not cover the main part of the cell is laminated with POE film (ethylene-octene copolymer) with strong water vapor barrier, transparent EVA film (ethylene-acetic acid) ethylene copolymer) and POE film (ethylene-octene copolymer) overlap;

C. The battery pieces are connected into battery strings by welding with ribbons, the distance between the battery pieces and the battery pieces is 2.5mm～4.5mm, the battery strings are arranged in parallel with the battery strings, and the distance between the battery strings is 2.5mm～4.5mm;

D. The second encapsulation film is a white EVA (ethylene-vinyl acetate copolymer) and POE (ethylene-octene copolymer) composite material, and a white EVA film (ethylene- Vinyl acetate copolymer), and the packaging parts with a distance of 10 to 50 mm from the edge of the module are laminated with POE films (ethylene-octene copolymers) with strong water vapor barrier; EVA film and POE film of the first packaging film and the second packaging film The dimensions are kept the same respectively; the EVA film and POE film selected in the first and second packaging films have similar hot-melt properties, and the melting temperature is close, and the melting temperature ranges from 60°C to 100°C;

E. The material of the back plate is glass or resin flat plate;

(2) placing the package stack in a laminator, evacuating and heating at a low temperature;

(3) bonding the package stack to form a laminate;

(4) taking out the laminate after cooling;

(5) After the busbars of the laminate are drawn out and connected to the junction box through the through holes on the backplane, a photovoltaic module is prepared.

To sum up, due to the adoption of the above-mentioned technical solutions, the beneficial effects of the present invention are:

1. The composite encapsulation structure adopted in the present invention can combine the advantages of EVA and POE materials. A transparent EVA film with high light transmittance is layered directly above the main body of the battery string, so as to achieve good optical absorption in the short wavelength range of the solar cell response, and the main body of the battery cell can achieve good optical absorption. The POE film with strong water vapor barrier is laminated around the part to ensure the safety and long-term aging resistance of the module in high temperature and high humidity environment, so that the module can be used for a long time.

2. The first encapsulation film and the second encapsulation film of the present invention are made of EVA and POE composite materials. EVA and POE have similar hot melt properties, and the melting temperature is close. After heating in the laminator, the alkyl group and the carbonyl group can form a good bond Combined, the actual operation is simple and easy to implement.

Description of drawings

Fig. 1 is a composite package structure diagram of a component;

2 is a schematic diagram of a first encapsulation film composite material;

3 is a schematic diagram of a second encapsulation film composite material;

FIG. 4 is a schematic diagram of a series connection of cells;

As shown in the picture: 1-panel, 2-first encapsulation film, 21-transparent EVA (ethylene-vinyl acetate copolymer) film, 22-POE (ethylene-octene copolymer) film, 3-battery sheet, 4- —Second encapsulation film, 41—white EVA (ethylene-vinyl acetate copolymer) film, 42—POE (ethylene-octene copolymer) film, 5—backplane, 6—busbar, 71—battery sheet The distance between the battery and the battery, 72—the distance between the battery string and the battery string.

Detailed ways

All features disclosed in this specification, or all disclosed steps in a method or process, may be combined in any way except mutually exclusive features and/or steps.

Any feature disclosed in this specification (including any accompanying claims, abstract), unless expressly stated otherwise, may be replaced by other equivalent or alternative features serving a similar purpose. That is, unless expressly stated otherwise, each feature is but one example of a series of equivalent or similar features.

As shown in FIG. 1, a composite packaging structure of a component includes a panel 1, a first packaging film 2, a battery sheet 3, a second packaging film 4 and a backplane 5. The panel 1, the first packaging film 2. The battery sheet 3 , the second encapsulation film 4 and the backplane 5 are stacked in sequence to form a laminate. The battery sheet 3 is provided with a busbar 6 , and the busbar 6 passes through the passages on the backplane 5 . After the holes are drawn out and connected to the junction box, the photovoltaic module is prepared.

The encapsulation method of the above-mentioned component includes the following steps:

1. Laminate the panel 1, the first encapsulation film 2, the battery sheet 3, the second encapsulation film 4 and the back plate 5 in sequence to form a laminate, and the battery sheet 3 is provided with a busbar 6;

Wherein, the panel 1 is a highly transparent glass, which must have high light transmission for wavelengths in the range of 350nm to 1200nm; as shown in FIG. 2 , the first encapsulation film 2 is transparent EVA (ethylene-vinyl acetate copolymerization material) film 21 and the composite material of POE (ethylene-octene copolymer) film 22, a transparent EVA film 21 (ethylene-vinyl acetate copolymer) with high light transmission is stacked directly above the main body of the battery sheet 3, and the periphery is 10 minutes away from the edge of the component. ~50mm, the packaging part that does not cover the main part of the battery sheet 3 is laminated with POE film 22 (ethylene-octene copolymer) with strong water vapor barrier, transparent EVA film 21 (ethylene-vinyl acetate copolymer) and POE film 22 ( As shown in Figure 4, the battery sheets 3 are connected by welding ribbons to form a battery string, the distance between the battery sheets and the battery sheets is 71 2.5mm ~ 4.5mm, and the battery strings are parallel to the battery strings. Arrangement, the distance between the battery string and the battery string is 72 2.5mm ~ 4.5mm; as shown in Figure 3, the second encapsulation film 4 is a white EVA (ethylene-vinyl acetate copolymer) film 41 and POE (ethylene-octene copolymer) Material) film 42 composite material, white EVA film (ethylene-vinyl acetate copolymer) 41 with high reflectivity is laminated directly under the main body of the battery string, and POE film ( Ethylene-octane copolymer) 42; The EVA film and POE film size of the first encapsulation film 2 and the second encapsulation film 4 are kept the same respectively; The film and POE film have similar hot-melt properties, the melting temperature is close, and the melting temperature ranges from 60°C to 100°C; the material of the back plate 5 is glass or resin flat plate;

2. Place the package stack in a laminator, vacuumize and heat at a low temperature;

3. Adhering the package stack to form a laminate;

4. Take out the laminate after cooling;

5. After the bus bars 6 of the laminate are drawn out and connected to the junction box through the through holes on the back plate 5, a photovoltaic module is prepared.

Compared with the existing conventional component encapsulation method, if the traditional photovoltaic module is used to encapsulate the EVA film for edge sealing, the advantage is that the light transmittance is greater than or equal to 91%, but the strength of the EVA film is low, and the water vapor transmission rate and water absorption rate are relatively low. Large, poor weather resistance, easy to cause film atomization, affecting the light transmittance, reducing the power generation of the module; if the traditional photovoltaic modules are packaged with POE film edge sealing, the advantages are: low water absorption and low water vapor transmission rate , good insulation, no acid release, excellent weather resistance, anti-PID has inherent advantages, the resistance value of EVA is generally 10 to the 14th power, but the uniformity of POE film is difficult to control and the transparency is poor, especially it cannot match the response band of black silicon solar cells. Achieving good optical matching directly affects the photoelectric conversion efficiency of the battery module and greatly increases the packaging loss of the module; the composite packaging structure of the module adopted in the present invention can combine the advantages of EVA and POE materials, and the battery string main body is stacked with high light transmittance directly above. The transparent EVA film can achieve good optical absorption in the short wavelength range of the solar cell response, and the POE film with strong water vapor barrier is laminated around the main body of the cell to ensure the safety of the module in high temperature and high humidity environment and long-term aging resistance. , so that the components can be used for a long time.

The specific embodiments described above further describe the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above-mentioned specific embodiments are only specific embodiments of the present invention and are not intended to limit the present invention. The present invention extends to any new features or any new combination disclosed in this specification, as well as any new method or process steps or any new combination disclosed.

Claims (12)

1. A composite packaging structure of a component, characterized in that, comprising a panel, a first packaging film, a battery sheet, a second packaging film and a backplane, the panel, the first packaging film, the battery sheet, the second The encapsulation film and the backplane are stacked in sequence to form a laminate, the cell is provided with a busbar, and the busbar is drawn out and connected to a junction box through a through hole on the backplane to prepare a photovoltaic module. 2 . The composite packaging structure of the component according to claim 1 , wherein the panel is made of high-transparency glass, which must have high transmittance for wavelengths in the range of 350 nm to 1200 nm. 3 . 3. The composite packaging structure of the assembly according to claim 1, wherein the first packaging film is a composite material of transparent EVA (ethylene-vinyl acetate copolymer) and POE (ethylene-octene copolymer) . 4 . The composite packaging structure of the module according to claim 1 , wherein the battery pieces are connected to a battery string by welding with ribbons, the distance between the battery pieces is 2.5mm to 4.5mm, and the battery strings are connected to the battery strings. 5 . Arranged in parallel, the battery string spacing is 2.5mm ~ 4.5mm. 5 . The composite packaging structure of the module according to claim 1 , wherein the second packaging adhesive film is a white EVA (ethylene-vinyl acetate copolymer) and POE (ethylene-octene copolymer) composite material. 6 . 6 . The composite packaging structure of the component according to claim 1 , wherein the back plate is a glass or resin flat plate. 7 . 7. The packaging method of a component according to claim 1, characterized in that, comprising the steps of: (1) Laminate the panel, the first encapsulation film, the battery sheet, the second encapsulation film and the backplane in sequence to form a laminate, and the battery sheet is provided with a busbar; (2) placing the package stack in a laminator, evacuating and heating at a low temperature; (3) bonding the package stack to form a laminate; (4) taking out the laminate after cooling; (5) After the busbars of the laminate are drawn out and connected to the junction box through the through holes on the backplane, a photovoltaic module is prepared. 8 . The packaging method of a component according to claim 7 , wherein the panel is made of high-transparency glass, which must have high transmittance for wavelengths in the range of 350 nm to 1200 nm. 9 . 9. The encapsulation method of a component according to claim 7, wherein the first encapsulation film is a composite of transparent EVA (ethylene-vinyl acetate copolymer) and POE (ethylene-octene copolymer) Material, a transparent EVA film (ethylene-vinyl acetate copolymer) with high light transmission is laminated directly above the main body of the cell, and the surrounding area is 10-50mm away from the edge of the module, and the packaging part directly above the main body of the cell is laminated with strong water vapor barrier properties. POE film (ethylene-octene copolymer), transparent EVA film (ethylene-vinyl acetate copolymer) and POE film (ethylene-octene copolymer) overlap. 10 . The packaging method of a component according to claim 7 , wherein the battery pieces are connected to a battery string by welding with a ribbon, the distance between the battery pieces is 2.5mm to 4.5mm, and the battery strings are connected to the battery pieces. 11 . The strings are arranged in parallel, and the distance between the battery strings is 2.5mm to 4.5mm. 11. The encapsulation method of a component according to claim 7, wherein the second encapsulation film is white EVA (ethylene-vinyl acetate copolymer) and POE (ethylene-octene copolymer) composite material , White EVA film (ethylene-vinyl acetate copolymer) with high reflectivity is laminated directly under the main body of the battery string, and POE film (ethylene-octene copolymer) with strong water vapor barrier is laminated on the packaging part 10-50mm away from the edge of the module. ; The size of the EVA film and the POE film of the first packaging film and the second packaging film are kept the same respectively; , the melting temperature range is 60 ℃ ~ 100 ℃. 12 . The packaging method of a component according to claim 7 , wherein the material of the back plate is glass or a resin flat plate. 13 .