Method for improving sealing performance of assembly

Abstract

The invention discloses a method for improving the sealing performance of a module, and relates to the field of photovoltaic module sealing, and the method comprises the following operation steps: S1, preparing raw materials including front plate glass, a first transparent adhesive film, a photovoltaic cell, a second transparent adhesive film and back plate glass; s2, preparing equipment; s3, performing scribing processing; s4, carrying out feeding treatment; s5, automatic series welding; s6, ultrasonic welding is conducted; s7, carrying out lamination treatment; and S8, packaging, storing and transporting. According to the method for improving the sealing performance of the assembly, the material cost during production of the photovoltaic assembly can be effectively reduced, an edge sealing adhesive tape does not need to be pasted in the production process, meanwhile, the cost of overall production equipment can be reduced, the adhesive tape tearing link can be omitted after lamination, adhesive tape tearing equipment is not needed, and the production efficiency is improved. On the basis, the overall production efficiency can be improved, manual operation steps are reduced, the production process is simplified, and the production efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the field of sealing of photovoltaic modules, and particularly relates to a method for improving the sealing performance of modules. Background Art

[0002] One of the core manufacturing processes of photovoltaic modules is the lamination process, the purpose of which is to laminate solar cells, encapsulation materials, glass backplates, etc. into one body through high temperature and high pressure to form a sealed and weather-resistant module structure. In traditional lamination processes, a lamination frame and edge-sealing tape are required, which specifically perform the following functions: The lamination frame is used to fix the laminated materials, such as glass, EVA / POE, solar cells, EVA / POE, backplates, etc., to prevent material displacement or deformation under high temperature and high pressure; by restricting the molten flow of the encapsulation material around the edges of the laminated parts through the frame, edge overflow of glue is reduced, and equipment contamination and appearance impact are avoided; the lamination frame cooperates with the laminator to form a sealed cavity for facilitating vacuum pumping to remove air bubbles. The edge-sealing tape is used to temporarily fix the edges of the laminate to prevent the encapsulation material from overflowing during lamination to form edge burrs.

[0003] Existing lamination processes rely on manual placement and removal of the lamination frame and rely on edge-sealing tape. Although they can ensure the sealing performance of the modules, there are problems such as low efficiency and high costs.

[0004] Therefore, it is necessary to propose a method for improving the sealing performance of modules to solve the above problems. Summary of the Invention

[0005] The main object of the present invention is to provide a method for improving the sealing performance of modules, which can effectively solve the problems in the background art.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows: A method for improving the sealing performance of modules, comprising the following operating steps: S1: Prepare raw materials, including front plate glass, first transparent adhesive film, photovoltaic cells, second transparent adhesive film, and back plate glass; S2: Prepare equipment, including a picosecond laser, an ultrasonic welding machine, a 6-axis vacuum manipulator, a vibrating disk, a CCD positioning device, a laser cleaning machine, and a welding head; S3: Perform scribing processing. Use a picosecond laser with a wavelength of 355 nm and a power of 30 W to cut the front plate glass, back plate glass, and photovoltaic cells. The laser cutting process for photovoltaic cells is as follows: speed 2 m / s, slit width 20 μm; the laser cutting processes for the front plate glass and back plate glass are speed 0.5 m / s and cutting depth 0.3 mm; S4: Perform loading processing. Use a 6-axis vacuum manipulator to load the front plate glass and back plate glass, and use a vibrating disk + CCD positioning to perform loading processing on the back plate glass; S5: Automatic series soldering. Use a 6-axis vacuum manipulator to fix the front plate glass, the first transparent adhesive film, the photovoltaic cell, the second transparent adhesive film, and the back plate glass to form a laminated structure. Use a laser cleaning machine to process the ultrasonic welding parts until the oxides and contaminants on the surface of the ultrasonic welding parts are removed. Perform spot welding on the pre-welding points using a laser welding process with a power of 20W, a pulse width of 5ms, and a spacing of 50mm. S6: Ultrasonic welding. Use four sets of 20kHz welding heads to cooperate in performing ultrasonic welding on the front plate glass, the first transparent adhesive film, the photovoltaic cell, the second transparent adhesive film, and the back plate glass, and fabricate a photovoltaic module based on this. S7: Lamination treatment. Perform lamination treatment on the photovoltaic module after ultrasonic welding, and control its temperature and vacuum gradient in five stages, where room temperature → 120°C (3min) → 145°C (12min) → 100°C (5min) → 60°C (3min). Control of the vacuum gradient: Initial vacuum degree: -95kPa (pumping speed 15m³ / min), pressure holding stage: -50kPa (pressure fluctuation < 1%). After lamination is completed, perform EL / IV detection on it, and take it out after the detection is qualified. S8: Encapsulation and storage and transportation. Perform protective treatment on the qualified photovoltaic module, spray an anti-PID coating, and install buffer pads at its four corners.

[0007] Preferably, the front plate glass, the back plate glass, and the photovoltaic cell are all equipped with RFID chips for tracking the batches of the front plate glass, the back plate glass, and the photovoltaic cell. The first transparent adhesive film is an EVA adhesive film, and the second transparent adhesive film is a POE adhesive film.

[0008] Preferably, the width of the ultrasonic welding part is 35mm, and the parameters of the laser cleaning machine are: wavelength 1064nm, power 80W, scanning speed 2m / s, and the surface roughness Ra of the ultrasonic welding part after cleaning ≤ 0.8μm.

[0009] Preferably, in S6, the welding process for the front plate glass, the first transparent adhesive film, and the photovoltaic cell is: frequency: 20kHz ± 0.5%, amplitude: 75μm, welding pressure: 0.5MPa, action time: 1.2s, pressure holding time: 3s, temperature control: 135 ± 2°C; the welding process for the photovoltaic cell and the second transparent adhesive film is: frequency: 28kHz ± 0.5%, amplitude: 60μm, welding pressure: 0.6MPa, action time: 0.8s, pressure holding time: 2.5s, temperature control: 145 ± 2°C.

[0010] Preferably, the thickness of the anti-PID coating is 2 - 3μm, and the coverage rate > 99%.

[0011] Compared with the prior art, the present invention provides a method for improving the sealing performance of components, which has the following beneficial effects: For the method of improving the sealing performance of components, after the original lamination process and before the glass combination process, the present invention adds a local ultrasonic welding process. The welding area is the four peripheral edges of the component with a width of 35 mm. When ultrasonic waves act on the contact surface of the first transparent adhesive film and the second transparent adhesive film, high-frequency vibrations of tens of thousands of times per second will be generated. Such high-frequency vibrations reaching a certain amplitude cause the molecules of the edge encapsulation material to generate heat through friction. Due to the poor thermal conductivity of the encapsulation materials of the first transparent adhesive film and the second transparent adhesive film, the heat is concentrated in the welding area, resulting in the melting of the contact surface of the first transparent adhesive film and the second transparent adhesive film. With a certain pressure applied, the encapsulation materials of the first transparent adhesive film and the second transparent adhesive film at the edge achieve local fusion. When the ultrasonic waves stop acting, the pressure is maintained for a few seconds to enable the completion of the cross-linking reaction and solidification molding. After local ultrasonic welding, there are no burrs, no pollution, and no glue overflow on the outer edge of the adhesive film. Based on this, the encapsulation materials around the glass edge of the component are fixed in advance, forming a seamless seal around it. The laminate can enter the laminator without pasting edge sealing tapes or placing a laminating frame. Under high temperature and high pressure, the encapsulation materials in the middle part of the component undergo normal cross-linking reactions. Since the encapsulation materials around the four edges have been fixed and formed, the colloid in the middle part of the component cannot flow to the glass edge to cause glue overflow; The method of the present invention can effectively reduce the material cost during the production of photovoltaic components. There is no need to paste edge sealing tapes during the production process, and at the same time, it can reduce the cost of the overall production equipment. After lamination, the tape tearing process can be omitted, and no tape tearing equipment is required. Based on this, the overall production efficiency can be improved, the manual operation steps can be reduced, the production process can be simplified, and the production efficiency can be increased, and it can also reduce... BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a schematic structural diagram of the whole of the present invention; Figure 2 is a top view of the present invention.

[0013] In the figure: 1, front plate glass; 2, first transparent adhesive film; 3, photovoltaic cell; 4, second transparent adhesive film; 5, back plate glass; 6, ultrasonic welding part. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0014] In order to make the technical means, creative features, achieved purposes and functions of the present invention easy to understand, the present invention will be further described below in conjunction with specific embodiments.

[0015] Example 1: As Figure 1 、 Figure 2 shown, a method for improving the sealing performance of components includes the following operating steps: S1: Prepare raw materials, including front panel glass 1, first transparent adhesive film 2, photovoltaic cell 3, second transparent adhesive film 4, and back panel glass 5. The front panel glass 1, back panel glass 5, and photovoltaic cell 3 are all equipped with RFID chips for tracking the batches of the front panel glass 1, back panel glass 5, and photovoltaic cell 3. The first transparent adhesive film 2 is an EVA adhesive film, and the second transparent adhesive film 4 is a POE adhesive film. The width of the ultrasonic welding part 6 is 35 mm. The parameters of the laser cleaning machine are: wavelength 1064 nm, power 80 W, scanning speed 2 m / s, and the surface roughness Ra of the ultrasonic welding part 6 after cleaning is ≤ 0.8 μm.

[0016] S2: Prepare equipment, including a picosecond laser, an ultrasonic welding machine, a 6-axis vacuum manipulator, a vibrating disk, a CCD positioning device, a laser cleaning machine, and a welding head.

[0017] S3: Dicing process. Use a picosecond laser with a wavelength of 355 nm and a power of 30 W to cut the front panel glass 1, back panel glass 5, and photovoltaic cell 3. The laser cutting process for the photovoltaic cell 3 is: speed 2 m / s, slit width 20 μm; the laser cutting processes for the front panel glass 1 and back panel glass 5 are speed 0.5 m / s and cutting depth 0.3 mm.

[0018] S4: Loading process. Use a 6-axis vacuum manipulator to load the front panel glass 1 and back panel glass 5, and use a vibrating disk + CCD positioning to load the back panel glass 5.

[0019] S5: Automatic string welding. Use a 6-axis vacuum manipulator to fix the front panel glass 1, first transparent adhesive film 2, photovoltaic cell 3, second transparent adhesive film 4, and back panel glass 5 to form a laminated structure. Use a laser cleaning machine to process the ultrasonic welding part 6 until the oxides and contaminants on the surface of the ultrasonic welding part 6 are removed. Use a laser electric welding process with a power of 20 W, a pulse width of 5 ms, and a spacing of 50 mm to perform spot welding on the pre-welding points.

[0020] S6: Ultrasonic welding. Use four sets of 20 kHz welding heads to cooperate to perform ultrasonic welding on the front panel glass 1, first transparent adhesive film 2, photovoltaic cell 3, second transparent adhesive film 4, and back panel glass 5. Based on this, a photovoltaic module is made. The welding process for the front panel glass 1, first transparent adhesive film 2, and photovoltaic cell 3 is: frequency: 20 kHz ± 0.5%, amplitude: 75 μm, welding pressure: 0.5 MPa, action time: 1.2 s, pressure holding time: 3 s, temperature control: 135 ± 2 °C; the welding process for the photovoltaic cell 3 and the second transparent adhesive film 4 is: frequency: 28 kHz ± 0.5%, amplitude: 60 μm, welding pressure: 0.6 MPa, action time: 0.8 s, pressure holding time: 2.5 s, temperature control: 145 ± 2 °C.

[0021] S7: Lamination process. After ultrasonic welding, the photovoltaic module is subjected to a lamination process with temperature control and vacuum gradient control in five stages, i.e., room temperature → 120°C (3 min) → 145°C (12 min) → 100°C (5 min) → 60°C (3 min). For the control of the vacuum gradient: initial vacuum degree: -95 kPa (pumping speed 15 m³ / min), pressure holding stage: -50 kPa (pressure fluctuation < 1%). After lamination, EL / IV detection is carried out on it. After passing the detection, it is taken out.

[0022] S8: Encapsulation and storage / transport. The qualified photovoltaic module is subjected to a protection process, spraying an anti-PID coating, and installing buffer pads at its four corners. The thickness of the anti-PID coating is 2 - 3 μm, and the coverage rate > 99%.

[0023] The performance of the method prepared by the present invention is compared with that of the prior art method. The prior art method is denoted as the comparative example, and the method of the present invention is denoted as the example. The following is the comparison table: Based on this, it can be known that the cost of the present invention can be effectively reduced.

[0024] After the original lamination process and before the glass combination process, the present invention adds a local ultrasonic welding process. The welding area is the peripheral edge of the module with a width of 35 mm. When ultrasonic waves act on the contact surface of the first transparent adhesive film 2 and the second transparent adhesive film 4, high-frequency vibrations of tens of thousands of times per second will be generated. This high-frequency vibration with a certain amplitude causes the molecules of the edge encapsulation material to generate heat through friction. Due to the poor thermal conductivity of the encapsulation materials of the first transparent adhesive film 2 and the second transparent adhesive film 4, the heat is concentrated in the welding area, resulting in the melting of the contact surface of the first transparent adhesive film 2 and the second transparent adhesive film 4. With a certain pressure applied, the encapsulation materials of the first transparent adhesive film 2 and the second transparent adhesive film 4 at the edge are locally fused. When the ultrasonic waves stop acting, the pressure is maintained for a few seconds to complete the cross-linking reaction and solidify into a shape. There are no burrs, no pollution, and no glue overflow on the outer edge of the adhesive film after local ultrasonic welding. Based on this, the encapsulation materials around the edges of the module glass are fixed in advance, forming a seamless seal around it. The laminated part can enter the laminator without pasting edge sealing tapes or placing a lamination frame. Under high temperature and high pressure, the encapsulation materials in the middle part of the module undergo normal cross-linking reactions. Since the encapsulation materials around the edges are already fixed in shape, the colloid in the middle part of the module cannot flow to the glass edge to cause glue overflow.

[0025] The foregoing has shown and described the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments, and what is described in the above embodiments and the specification is only to illustrate the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention will also have various changes and improvements, and these changes and improvements fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for improving the sealing performance of components, characterized in that: It includes the following operation steps: S1: Prepare raw materials, including a front plate glass (1), a first transparent adhesive film (2), a photovoltaic cell (3), a second transparent adhesive film (4), and a back plate glass (5); S2: Prepare equipment, including a picosecond laser, an ultrasonic welding machine, a 6-axis vacuum manipulator, a vibratory bowl feeder, a CCD positioning device, a laser cleaning machine, and a welding head; S3: Perform scribing. Use a picosecond laser with a wavelength of 355 nm and a power of 30 W to cut the front plate glass (1), the back plate glass (5), and the photovoltaic cell (3). The laser cutting process for the photovoltaic cell (3) is: speed 2 m / s, slit width 20 μm; the laser cutting processes for the front plate glass (1) and the back plate glass (5) are speed 0.5 m / s and cutting depth 0.3 mm; S4: Perform loading. Use a 6-axis vacuum manipulator to load the front plate glass (1) and the back plate glass (5), and use a vibratory bowl feeder + CCD positioning to perform the loading process on the back plate glass (5); S5: Automatically string weld. Use a 6-axis vacuum manipulator to fix the front plate glass (1), the first transparent adhesive film (2), the photovoltaic cell (3), the second transparent adhesive film (4), and the back plate glass (5) to form a laminated structure. Use a laser cleaning machine to process the ultrasonic welding part (6) until the oxides and contaminants on the surface of the ultrasonic welding part (6) are removed. Use a laser electric welding process with a power of 20 W, a pulse width of 5 ms, and a spacing of 50 mm to perform spot welding on the pre-welding points; S6: Perform ultrasonic welding. Use four sets of 20 kHz welding heads to cooperate to perform ultrasonic welding on the front plate glass (1), the first transparent adhesive film (2), the photovoltaic cell (3), the second transparent adhesive film (4), and the back plate glass (5), and thus make a photovoltaic module; S7: Perform lamination. Perform lamination on the ultrasonic welded photovoltaic module, and control the temperature and vacuum gradient in five stages, where room temperature → 120 °C (3 min) → 145 °C (12 min) → 100 °C (5 min) → 60 °C (3 min), and the control of the vacuum gradient: initial vacuum degree: -95 kPa (pumping speed 15 m³ / min), pressure holding stage: -50 kPa (pressure fluctuation < 1%). After lamination is completed, perform EL / IV detection on it, and take it out after the detection is qualified; S8: Package and store and transport. Perform protective treatment on the qualified photovoltaic module, spray an anti-PID coating, and install buffer pads at its four corners.

2. The method for improving the sealing performance of a component according to claim 1, characterized in that: The front plate glass (1), the back plate glass (5), and the photovoltaic cell (3) are all equipped with RFID chips, which are used to track the batches of the front plate glass (1), the back plate glass (5), and the photovoltaic cell (3). The first transparent adhesive film (2) is an EVA adhesive film, and the second transparent adhesive film (4) is a POE adhesive film.

3. A method for improving the sealing performance of a component according to claim 1, characterized in that: The width of the ultrasonic welding part (6) is 35 mm, and the parameters of the laser cleaning machine are: wavelength 1064 nm, power 80 W, scanning speed 2 m / s, and the surface roughness Ra of the ultrasonic welding part (6) after cleaning ≤ 0.8 μm.

4. A method for improving the sealing performance of a component according to claim 1, wherein: In S6, the welding process of the front panel glass (1), the first transparent adhesive film (2) and the photovoltaic cell (3) is as follows: frequency: 20 kHz ± 0.5%, amplitude: 75 μm, welding pressure: 0.5 MPa, action time: 1.2 s, pressure holding time: 3 s, temperature control: 135 ± 2 °C; the welding process of the photovoltaic cell (3) and the second transparent adhesive film (4) is as follows: frequency: 28 kHz ± 0.5%, amplitude: 60 μm, welding pressure: 0.6 MPa, action time: 0.8 s, pressure holding time: 2.5 s, temperature control: 145 ± 2 °C.

5. A method for improving the sealing performance of a component according to claim 4, characterized in that: The thickness of the anti-PID coating is 2 - 3 μm, and the coverage rate > 99%.

Images