Solar cell module recycling method

Abstract

The invention provides a solar cell module recycling method, which comprises the following steps of S1, irradiating from the upper part of photovoltaic glass by adopting laser to enable a focus to be positioned at the upper part of a packaging layer; enabling the laser and the photovoltaic laminated piece to move relatively until the whole breadth of the photovoltaic laminated piece is irradiated, and enabling the packaging layer close to the photovoltaic glass to be invalid; s2, cooling; s3, applying mechanical force to the photovoltaic glass to separate the photovoltaic glass from the packaging layer; wherein in the step S3, the photovoltaic glass of the photovoltaic laminated part is pulled up and down or horizontally rotated, so that the photovoltaic glass is separated from the packaging layer. Compared with a traditional recovery mode, a laser processing scheme is utilized, laser irradiation is adopted to enable the packaging layer to be invalid and lose viscidity, so that efficient separation of the photovoltaic module is achieved, the recovery effect is good, no packaging layer adhesive film is left on the complete surface of photovoltaic glass during separation, the inner layer of the packaging layer is not damaged, a battery piece completely exists in an interlayer of the packaging layer, and the service life of the battery piece is prolonged. And the packaging layer and the battery piece can be further separated.

Description

Technical Field

[0001] The present invention belongs to the field of laser processing, and in particular relates to a method for recycling solar cell modules. Background Art

[0002] With the market changes, photovoltaic cell modules are gradually widely used. During the production process, some unqualified products will be generated, and more and more waste products will be produced during the long-term use. For unqualified and waste products, recycling and reuse can reduce resource waste and environmental pollution.

[0003] The main difficult parts to disassemble in photovoltaic cell modules are single-sided or double-sided glass, encapsulation layers (such as EVA glue), and solar cells. The existing methods for recycling modules mainly include physical disassembly after heat treatment, thermal cutting, chemical reagent immersion, etc. These methods all have certain disadvantages. Physical disassembly after heat treatment is prone to the problem of backplane adhesion; thermal cutting separation is likely to cause the adhesion of EVA, and it is necessary to further remove the waste adhered to the glass by means such as ultrasonic or polishing. Chemical reagent immersion takes a long time and is not environmentally friendly. Summary of the Invention

[0004] In this application, a laser is scanned from above the glass and irradiated onto the encapsulation layer to make it ineffective. After cooling, mechanical force is used to separate the glass from the encapsulation layer. There is no adhesion between the glass and the encapsulation layer, and the decomposed glass does not require further treatment.

[0005] To achieve the above object, the technical solutions adopted in the embodiments of this application are as follows:

[0006] A method for recycling solar cell modules includes the following steps:

[0007] S1: Irradiate from one side of the photovoltaic glass with a laser, so that the focus is located at the photovoltaic glass of the encapsulation layer close to the light incident side; move the laser relative to the photovoltaic laminate until the entire surface of the photovoltaic laminate is irradiated, making the encapsulation layer close to the photovoltaic glass ineffective;

[0008] S2: Cool down;

[0009] S3: Apply mechanical force to the photovoltaic glass to separate the photovoltaic glass from the encapsulation layer;

[0010] Among them, S3 specifically means pulling the photovoltaic glass of the photovoltaic laminate up and down or rotating it horizontally to separate the photovoltaic glass from the encapsulation layer.

[0011] In some embodiments, in the method for recycling solar cell modules of this application, in S1, the focus of the laser is located at the joint surface of the light incident side photovoltaic glass and the encapsulation layer, and penetrates 0.6 mm into the encapsulation layer.

[0012] In some embodiments, for the method of recycling a solar cell module of the present application, the laser wavelength is 500 nm to 2 μm, corresponding to the non-cell region, the laser power is 100 - 250 W, corresponding to the cell region, the laser power is 200 W - 500 W; and the laser power corresponding to the non-cell region is less than the laser power corresponding to the cell region; the action time is 50 - 80 s.

[0013] In some embodiments, for the method of recycling a solar cell module of the present application,

[0014] In S1, the laser is moved relative to the photovoltaic laminate until the entire surface of the photovoltaic laminate is irradiated. The laser scanning path is to scan a closed frame area along the periphery of the photovoltaic laminate and shrink inward, continue to scan the closed area until reaching the position corresponding to the cell, and continue to shrink inward until the entire surface of the photovoltaic laminate is irradiated.

[0015] In some embodiments, for the method of recycling a solar cell module of the present application, for a photovoltaic laminate with photovoltaic glass on both the top and bottom, in S1, the laser is irradiated simultaneously from above and below the photovoltaic glass so that the focus is at the photovoltaic glass near the light incident side of the encapsulation layer; the laser is moved relative to the photovoltaic laminate until the entire surface of the photovoltaic laminate is irradiated, causing the encapsulation layer near the photovoltaic glass to fail.

[0016] In some embodiments, for the method of recycling a solar cell module of the present application, S2 is natural cooling.

[0017] In some embodiments, for the method of recycling a solar cell module of the present application, in S3, when applying a mechanical force to the photovoltaic glass to separate the photovoltaic glass and the encapsulation layer, the mechanical force is applied sequentially from one edge to the other edge, or from the outer periphery of the edge to the inside in sequence.

[0018] In some embodiments, for the method of recycling a solar cell module of the present application, in S3, when applying a mechanical force to the photovoltaic glass to separate the photovoltaic glass and the encapsulation layer, specifically, the photovoltaic laminate is fixed on the workbench, a suction cup array is arranged above, the photovoltaic glass of the photovoltaic laminate is adsorbed, and the suction cup pulls upward to separate the photovoltaic glass.

[0019] In some embodiments, for the method of recycling a solar cell module of the present application, in S3, when applying a mechanical force to the photovoltaic glass to separate the photovoltaic glass and the encapsulation layer, it includes

[0020] S31 uses a suction cup array to pull the photovoltaic glass of the photovoltaic laminate upward to separate one side of the photovoltaic film;

[0021] S32 flips and uses a suction cup array to pull the photovoltaic glass of the photovoltaic laminate upward to separate the other side of the photovoltaic film.

[0022] In some embodiments, the method for recycling a solar cell module of the present application further includes steps before S1.

[0023] S01 A step of preprocessing the crushing area. The crushing area is scanned by a laser, and then the glass in the crushing area is sucked by a suction cup at its corresponding position to complete the separation of the glass in the crushing area.

[0024] The beneficial effects of the embodiments of the present application include:

[0025] Compared with the traditional recycling method, the present invention uses a laser processing solution. By using laser irradiation, the encapsulation layer is made to fail and lose its adhesiveness, thereby realizing the efficient separation of the photovoltaic module, and the recycling effect is better. When separating, the complete surface of the photovoltaic glass does not remain with the encapsulation layer adhesive film, and the inner layer of the encapsulation layer is not damaged. The solar cells are completely present in the sandwich of the encapsulation layer, and further separation of the encapsulation layer and the solar cells can be carried out. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0027] Figure 1 One of the flowcharts of the method for recycling a solar cell module according to an embodiment of the present application;

[0028] Figure 2 Another flowchart of the method for recycling a solar cell module according to an embodiment of the present application.

[0029] Figure 3 A schematic diagram of step S1 of the method for recycling a solar cell module according to an embodiment of the present application;

[0030] Figure 4 A schematic diagram of a laser scanning path according to an embodiment of the present application;

[0031] Figure 5 Another schematic diagram of a laser scanning path according to an embodiment of the present application;

[0032] Figure 6 Another schematic diagram of a laser scanning path according to an embodiment of the present application;

[0033] Figure 7 A schematic diagram of step S3 of the method for recycling a solar cell module according to an embodiment of the present application;

[0034] Figure 8It is the third flowchart of the solar cell module recycling method according to the embodiment of the present application;

[0035] Figure 9 It is the fourth flowchart of the solar cell module recycling method according to the embodiment of the present application;

[0036] Icon: Photovoltaic glass 1, encapsulation layer, 2, cell area 3, laser processing module 4, suction cup array 5. Detailed implementation manners

[0037] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are some, but not all, of the embodiments of the present application. It should be noted that, without conflict, the various features in the embodiments of the present application can be combined with each other, and the combined embodiments are still within the protection scope of the present application.

[0038] In the description of the present application, unless otherwise specified, the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present application and simplifying the description, and thus cannot be construed as a limitation to the present application. In addition, unless otherwise specified, terms such as "first", "second", "third", etc. are only used for distinguishing descriptions, and cannot be construed as indicating or implying relative importance.

[0039] The embodiment of the present application provides a solar cell module recycling method. Refer to Figures 1 to 3 , wherein Figure 1 is the first flowchart of the solar cell module recycling method, Figure 3 is the second flowchart of the solar cell module recycling method, Figure 2 is the schematic diagram of step S1 of the solar cell module recycling method.

[0040] Refer to Figure 1 , the solar cell module recycling method of the present application includes S0 disassembling the photovoltaic module to obtain an aluminum frame, a junction box and a photovoltaic laminate. The method of the present invention mainly relates to the disassembly and recycling of this photovoltaic laminate. Refer to Figure 3 , the solar photovoltaic laminate usually includes a photovoltaic glass 1 arranged on the outermost side, an encapsulation layer 2 inside the photovoltaic glass, and a cell area 3 where a plurality of cells connected by solder tapes are located inside the encapsulation layer.

[0041] It should be noted that when the encapsulation layer is prepared for the solar cell module, it is formed by hot pressing encapsulation materials such as EVA, POE (polyolefin elastomer) film, EPE (composed of two layers of EVA and one layer of POE), and PVB (polyvinyl butyral) through hot pressing encapsulation. In this embodiment, EVA is taken as an example.

[0042] See Figure 2 , specifically, the method for recycling the solar cell module of the present invention includes the following steps:

[0043] S1: Irradiate from one side of the photovoltaic glass with a laser so that the focus is located at the photovoltaic glass on the light incident side of the encapsulation layer; move the laser relative to the photovoltaic laminate until the entire surface of the photovoltaic laminate is irradiated, causing the encapsulation layer close to the photovoltaic glass to fail.

[0044] S2: Cool the photovoltaic laminate.

[0045] S3: Apply mechanical force to the photovoltaic glass to separate the photovoltaic glass and the encapsulation layer.

[0046] Among them, in S1, the wavelength of the laser is 500 nm to 2 μm, and preferably infrared laser is used. In this embodiment, a laser with a wavelength of 1064 nm is used. The focus position of the laser is located at the position of the encapsulation layer close to the light incident side photovoltaic glass. More specifically, the focus of the laser is located at any position between the bonding surface of the light incident side photovoltaic glass and the encapsulation layer and 0.6 mm deep into the encapsulation layer.

[0047] By selecting the above laser wavelength and setting the focus position, the present invention enables the laser to penetrate the photovoltaic glass layer and act on the position of the encapsulation layer close to the photovoltaic glass, causing it to fail and lose its adhesiveness, facilitating the subsequent disassembly of the photovoltaic glass by mechanical force. Specifically, after the laser passes through the glass and acts on the interface between the glass and the encapsulation layer, the temperature rises, and the encapsulation layer decomposes. On the one hand, the adhesion to the glass decreases, and on the other hand, gases such as carbon monoxide and carbon dioxide are generated during decomposition, which reversely promotes the separation between the glass and the film.

[0048] When scanning the photovoltaic laminate, the single surface area is 25 - 50 mm × 200 - 220 mm, and the action time is 50 - 80 s, preferably 60 s. Among them, for the non-cell area, the power of the laser is 100 - 250 W. In this embodiment, it is 200 W. For the cell area, the power of the laser is 200 W - 500 W. In this embodiment, it is 300 W. The laser power corresponding to the non-cell area is less than the laser power corresponding to the cell area.

[0049] In the present invention, different powers are applied to the non-cell region and the cell region for a certain period of time. On the one hand, the encapsulation layer at the edge is made to fail and is thus easily separated. On the other hand, the influence caused by the absorption of the cells in the cell region is overcome, making it easier for the entire encapsulation layer to be separated from the photovoltaic glass.

[0050] In S1, the laser is moved relative to the photovoltaic laminate until the entire surface of the photovoltaic laminate is irradiated. Specifically, the laser scanning path can be seen in Figures 4 to 6 , which is a schematic diagram of the laser scanning path. Specifically, see Figure 4 , as an implementation, from one side of the photovoltaic laminate, first scan a longitudinal strip region and gradually advance until the other side is scanned.

[0051] Or the laser scanning path is: see Figure 5 , scan a closed frame region along the periphery of the photovoltaic laminate, shrink it inward, continue to scan the closed region until the position corresponding to the cell is reached, and then from one side, first scan a longitudinal strip region and gradually advance until the other side is scanned. More preferably, see Figure 6 , at the position corresponding to the cell, the scanning can continue to be carried out in a shrinking manner inward until the center position of the photovoltaic laminate is scanned.

[0052] When the present invention scans the photovoltaic laminate, different laser powers are used for the region corresponding to the cell and the region without cells, and during scanning, from the periphery to the inside. This makes it easier for the encapsulation layer at the edge to be separated from the photovoltaic glass, without damaging the solar cells, and the encapsulation layer near the inner layer of the cell does not fail. In this way, after separating the glass and the encapsulation layer, the encapsulation layer covering the cell can be further separated by hot melting or other means to ensure the integrity of the cell.

[0053] Furthermore, when the present invention performs laser scanning, the method of gradually shrinking from the outside to the inside is adopted, which can reduce the tensile stress effect of the unirradiated and unmodified encapsulation layer adjacent to it after irradiating a single surface, so that when the subsequent encapsulation layer is separated from the photovoltaic glass, the influence of the un-failed encapsulation layer around the failed encapsulation layer region on its tensile stress is reduced.

[0054] It should be noted that for the single-glass module, the above-mentioned completion of the irradiation of the entire surface of the photovoltaic laminate means that a laser with a certain irradiation surface (the illustrated single surface) irradiates from above the photovoltaic glass towards the photovoltaic glass, and the laser or the photovoltaic laminate is moved to splice the single surfaces until the entire surface of the photovoltaic laminate is covered.

[0055] For the double-glass module, that is Figure 1As shown, for the component with photovoltaic glass on both the upper and lower sides, it is possible to first complete the irradiation of the entire area of the upper photovoltaic laminate, and then complete the irradiation of the entire area of the lower photovoltaic laminate. More preferably, in this embodiment, the upper and lower sides of the photovoltaic laminate are irradiated with a laser simultaneously, with the focus located at the photovoltaic glass near the light incident side of the encapsulation layer, which saves more time.

[0056] In S2, the photovoltaic laminate is cooled by natural cooling.

[0057] In S3, the mechanical separation method is to use manual or mechanical means to pull the photovoltaic laminate up and down or rotate it horizontally to separate the photovoltaic glass from the encapsulation layer.

[0058] Specifically, in the present invention, the photovoltaic laminate is fixed on the workbench, and a suction cup array is arranged above to adsorb the photovoltaic laminate. Specifically, the photovoltaic glass of the photovoltaic laminate is adsorbed, and then the upper suction cup array pulls upward to disassemble the photovoltaic glass, or the upper suction cup adsorbs the photovoltaic glass and rotates it horizontally to disassemble the photovoltaic glass.

[0059] As a specific implementation method, the photovoltaic laminate can be fixed on the workbench through a clamping member, or the workbench is a negative pressure adsorption workbench, or a suction cup array is arranged on the workbench to adsorb and fix the photovoltaic laminate. Refer to Figure 7 , which is a schematic structural diagram of step S3 of the solar cell module recycling method according to the embodiment of the present application.

[0060] During specific implementation, the upper suction cup array starts to rise sequentially from one side of the edge of the photovoltaic laminate to the other side to separate the photovoltaic glass. As another preferred implementation method, the suction cup array starts to rise sequentially from the periphery to the inside to separate the photovoltaic glass.

[0061] When the present invention uses mechanical force to separate the photovoltaic laminate, a method of gradually applying mechanical force from one side of the edge to the other side, or from the edge periphery to the inside, can make the photovoltaic glass gradually separate from the encapsulation layer from one side to the other side, or from the periphery to the inside, thereby completing the recycling of the photovoltaic glass module. On the one hand, starting from the edge for separation avoids damage to the inner solar cells. On the other hand, more time can be reserved for internal cooling to facilitate separation.

[0062] It can be understood that although the same laser process is used to process the upper and lower sides of the photovoltaic laminate in step S1, when the photovoltaic glass is mechanically separated in step S3, it is possible that the upper and lower photovoltaic glasses are not separated simultaneously. In this case, two mechanical separations can be performed. That is, when the above method is used for mechanical separation, if only the photovoltaic glass on the upper surface is separated from the encapsulation layer and the glass on the lower surface is not separated, the glass on the lower surface is separated again. Specifically, it can be turned over as a whole and separated again.

[0063] Specifically, refer to Figure 8 , Figure 8 which is the third flowchart of the solar cell module recycling method. S3 includes: S31 using a suction cup array to pull the photovoltaic glass of the photovoltaic laminate upward to separate one side of the photovoltaic thin film;

[0064] S32 flip, and use a suction cup array to pull the photovoltaic glass of the photovoltaic laminate upward to separate the other side of the photovoltaic thin film.

[0065] As a further technical solution, sometimes part of the photovoltaic glass of the photovoltaic laminate is broken. Refer to Figure 9 which is the fourth flowchart of the solar cell module recycling method. At this time, when performing the foregoing steps of the present invention, it further includes the step S01 of preprocessing the broken area. Specifically, use laser to scan the broken area, and then suck the glass in the broken area with the suction cup at its corresponding position to complete the splitting; then, perform laser scanning and mechanical separation on the rest. For the glass component in the burst state, the laser scanning path is not restricted.

[0066] The above are only the preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for recycling a solar cell module, characterized in that: including the following steps, S1: irradiate from one side of the photovoltaic glass with a laser so that the focus is located at the photovoltaic glass of the encapsulation layer close to the light incident side; move the laser relative to the photovoltaic laminate until the entire area of the photovoltaic laminate is irradiated, causing the encapsulation layer close to the photovoltaic glass to fail; S2: cool down; S3: apply mechanical force to the photovoltaic glass to separate the photovoltaic glass from the encapsulation layer; wherein, S3 specifically means pulling the photovoltaic glass of the photovoltaic laminate up and down or rotating it horizontally to separate the photovoltaic glass from the encapsulation layer.

2. The method for recycling a solar cell module according to claim 1, characterized in that: In S1, the focus of the laser is located at the joint surface of the light incident side photovoltaic glass and the encapsulation layer, and penetrates 0.6 mm into the encapsulation layer.

3. The method for recycling a solar cell module according to claim 1, characterized in that: The wavelength of the laser is 500 nm to 2 μm, corresponding to the non-cell area, the power of the laser is 100 - 250 W, corresponding to the cell area, the power of the laser is 200 W - 500 W; and the laser power corresponding to the non-cell area is less than the laser power corresponding to the cell area; the action time is 50 - 80 s for both.

4. The method for recycling a solar cell module according to claim 1, characterized in that: In S1, move the laser relative to the photovoltaic laminate until the entire area of the photovoltaic laminate is irradiated. The laser scanning path is to scan a closed frame area along the periphery of the photovoltaic laminate and shrink inward, continue to scan the closed area until reaching the position corresponding to the cell, and continue to shrink inward until the entire area of the photovoltaic laminate is irradiated.

5. The method for recycling a solar cell module according to claim 1, characterized in that: For a photovoltaic laminate with photovoltaic glass on both the upper and lower sides, in S1, irradiate from above and below the photovoltaic glass with a laser simultaneously so that the focus is located at the photovoltaic glass of the encapsulation layer close to the light incident side, move the laser relative to the photovoltaic laminate until the entire area of the photovoltaic laminate is irradiated, causing the encapsulation layer close to the photovoltaic glass to fail.

6. The method for recycling a solar cell module according to claim 1, characterized in that: S2 cooling is natural cooling.

7. The method for recycling a solar cell module according to claim 1, characterized in that: When applying mechanical force to the photovoltaic glass in S3 to separate the photovoltaic glass from the encapsulation layer, the mechanical force is applied sequentially from one edge to the other edge, or from the outer periphery of the edge to the inside in turn.

8. The method for recycling a solar cell module according to claim 7, characterized in that: When applying mechanical force to the photovoltaic glass in S3 to separate the photovoltaic glass from the encapsulation layer, specifically, fix the photovoltaic laminate on the workbench, set a suction cup array above, adsorb the photovoltaic glass of the photovoltaic laminate, and pull the suction cup upward to separate the photovoltaic glass.

9. The method for recycling a solar cell module according to claim 7 or 8, characterized in that: Applying mechanical force to the photovoltaic glass in S3 to separate the photovoltaic glass from the encapsulation layer includes, S31: use a suction cup array to pull the photovoltaic glass of the photovoltaic laminate upward to separate one side of the photovoltaic thin film; S32: flip it, use a suction cup array to pull the photovoltaic glass of the photovoltaic laminate upward to separate the other side of the photovoltaic thin film.

10. The method for recycling a solar cell module according to claim 1, characterized in that: It also includes the steps before S1, S01: a step of pre-treating the broken area. Scan the broken area with a laser, and then suck the glass in the broken area with the suction cup at its corresponding position to complete the splitting of the glass in the broken area.

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