Photovoltaic module and photovoltaic power generation system
By thickening the gaps between the cells and between the cells and the frame in the second encapsulation layer of the photovoltaic module, the problem of thickness reduction caused by the inflow of encapsulation layer material into the gaps is solved, thereby reducing production costs and improving encapsulation performance.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- ZHEJIANG AIKO SOLAR ENERGY TECH CO LTD
- Filing Date
- 2025-05-14
- Publication Date
- 2026-06-18
AI Technical Summary
During the lamination process of existing photovoltaic modules, the encapsulation layer material flows into the gaps between the cells and between the cells and the frame, resulting in a thinner encapsulation layer and an increased cost of using the encapsulation layer.
By thickening the gaps between the cells and between the cells and the frame in the second encapsulation layer of the photovoltaic module, the gaps are filled by using a filler film or by directly increasing the thickness, and the thickness of the non-gap parts is reduced. The thickness of the second encapsulation layer is set to 180-380 micrometers.
This reduces the production cost of photovoltaic modules while maintaining good encapsulation performance, reduces the amount of encapsulation layer material used, and improves production yield and structural stability.
Smart Images
Figure CN2025094948_18062026_PF_FP_ABST
Abstract
Description
A photovoltaic module and a photovoltaic power generation system
[0001] Cross-reference to related applications
[0002] This disclosure claims priority to Chinese patent application No. 202423062723.2 filed on December 12, 2024 with the China National Intellectual Property Administration, entitled “A Photovoltaic Module and Photovoltaic Power Generation System”, the entire contents of which are incorporated herein by reference. Technical Field
[0003] This disclosure relates to the field of photovoltaic module technology, specifically to a photovoltaic module and a photovoltaic power generation system. Background Technology
[0004] Photovoltaic power generation utilizes solar-grade semiconductor electronic devices to effectively absorb solar radiation energy and convert it into electrical energy. A photovoltaic module mainly consists of a frame and laminated components fixed within the frame. The laminated components include a front panel, upper encapsulation layer, cell layer, lower encapsulation layer, and back panel. The laminated components are formed through vacuum thermal lamination and then encapsulated using the frame. Multiple cell strings are connected in series, parallel, or series-parallel to form cell layers. During the lamination process, air trapped between the layers of the photovoltaic module is extracted through vacuuming, and then the encapsulation layer is melted by heating, bonding the front panel, upper encapsulation layer, cell layer, lower encapsulation layer, and back panel together.
[0005] In related technologies, during the lamination process of photovoltaic modules, gaps exist between adjacent cells and between edge cells and the frame. As the encapsulation layer melts during lamination, some encapsulation material enters these gaps, causing thinning of the encapsulation layer in these areas. This affects the encapsulation performance. To improve encapsulation performance, a thickness of at least 400 micrometers is required, resulting in a thicker overall encapsulation layer. This significantly increases the cost of using the encapsulation layer, leading to high production costs for photovoltaic modules.
[0006] Public content
[0007] This disclosure provides a photovoltaic module designed to address the problem of high production costs in existing photovoltaic modules due to the high cost of the encapsulation layer.
[0008] This disclosure provides a photovoltaic module, including a frame and a laminate fixed within the frame. The laminate includes a first cover plate, a first encapsulation layer, a cell layer, a second encapsulation layer, and a second cover plate stacked sequentially. The cell layer includes a plurality of cells, with a first gap between adjacent cells and a second gap between the cells at the edge of the cell layer and the frame.
[0009] The portion of the second encapsulation layer corresponding to the first gap has a first thickness, the portion of the second encapsulation layer corresponding to the second gap has a second thickness, and the portion of the second encapsulation layer corresponding to the battery cell has a third thickness, the third thickness being 180 to 380 micrometers, and both the first and second thicknesses being greater than the third thickness.
[0010] In some embodiments, the cell layer includes at least one cell string, with the cells within each cell string connected by solder strips.
[0011] In some embodiments, the thickness of the solder strip is 0.07 to 0.3 mm and the width is 0.5 to 3 mm.
[0012] In some embodiments, the area of the second encapsulation layer near the second cover plate corresponding to the solder strip is planar, or the area of the second encapsulation layer near the second cover plate corresponding to the solder strip protrudes toward the second cover plate.
[0013] In some embodiments, the area of the second encapsulation layer near the second cover plate corresponding to the first gap is planar; or, the area of the second encapsulation layer near the second cover plate corresponding to the first gap protrudes toward the second cover plate to form a first protrusion.
[0014] In some embodiments, the area of the second encapsulation layer near the second cover plate corresponding to the second gap is planar; or, the area of the second encapsulation layer near the second cover plate corresponding to the second gap protrudes toward the second cover plate to form a second protrusion.
[0015] In some embodiments, the second encapsulation layer includes an adhesive film and a filler film, with the filler film disposed between the second cover plate and the adhesive film; or, the filler film is disposed between the adhesive film and the battery cell layer; the filler film includes a first filling portion corresponding to the first gap position and a second filling portion corresponding to the second gap.
[0016] In some embodiments, the filler film and the adhesive film are an integral structure.
[0017] In some embodiments, the filler film and the adhesive film are separate structures.
[0018] In some embodiments, the filler film is bonded between the second cover plate and the adhesive film, or the filler film is bonded between the adhesive film and the battery cell layer.
[0019] In some embodiments, the width of the first filling portion is greater than the width of the first gap.
[0020] In some embodiments, the width of the second filling portion is greater than the width of the second gap.
[0021] In some embodiments, the thickness of both the first filling portion and the second filling portion is 80 to 400 micrometers.
[0022] In some embodiments, the thickness of both the first filling portion and the second filling portion is 200 to 250 micrometers.
[0023] In some embodiments, the filler film and the adhesive film are made of the same material, and the pre-crosslinking degree of the filler film is greater than that of the adhesive film.
[0024] In some embodiments, the ratio of the pre-crosslinking degree of the filler film to the pre-crosslinking degree of the adhesive film is 5 to 30.
[0025] In some embodiments, the pre-crosslinking degree of the filler film and adhesive film is 0 to 60%.
[0026] In some embodiments, the filler film and the adhesive film are different materials.
[0027] In some embodiments, the third thickness is 200 to 250 micrometers.
[0028] In some embodiments, the ratio of the thickness of the first thickness and the second thickness to the thickness of the third thickness is 1.2 to 3.
[0029] This disclosure also provides a photovoltaic power generation system, including the photovoltaic modules described above.
[0030] The present disclosure discloses a photovoltaic module in which the second encapsulation layer has a first thickness corresponding to the gap between adjacent cells, a second thickness corresponding to the gap between the cells and the frame, and a third thickness corresponding to the cells. By setting the first and second thicknesses to be greater than the third thickness, only the portions of the second encapsulation layer corresponding to the first and second gaps are thickened. This allows the material of the thickened portion of the second encapsulation layer corresponding to the first gap to fill the first gap during lamination, and the material of the thickened portion of the second encapsulation layer corresponding to the second gap to fill the second gap during lamination. The second encapsulation layer does not need to be thickened as a whole, which can reduce the thickness design of the portions of the second encapsulation layer that do not correspond to the first and second gaps. The third thickness of the second encapsulation layer can be set to 180-380 micrometers. Compared with the encapsulation layer thickness of conventional photovoltaic modules, the amount of material used in the second encapsulation layer is reduced, thereby reducing the production cost of the photovoltaic module, while achieving good encapsulation performance of the second encapsulation layer. Attached Figure Description
[0031] Figure 1 is a cross-sectional schematic diagram of a photovoltaic module provided in an embodiment of this disclosure;
[0032] Figure 2 is a cross-sectional schematic diagram of another photovoltaic module provided in an embodiment of this disclosure;
[0033] Figure 3 is a schematic diagram of a photovoltaic module before lamination according to an embodiment of this disclosure;
[0034] Figure 4 is a schematic diagram of another photovoltaic module before lamination according to an embodiment of this disclosure.
[0035] Figure 5 is a schematic diagram of a filling film for a photovoltaic module provided in an embodiment of this disclosure;
[0036] Figure 6 is a cross-sectional view along the AA direction in Figure 5.
[0037] The above-mentioned figures include the following reference numerals: 1. Frame; 2. Laminated component; 3. First cover plate; 4. First encapsulation layer; 5. Battery cell layer; 51. Battery cell; 52. First gap; 53. Second gap; 6. Second encapsulation layer; 61. First protrusion; 62. Second protrusion; 63. Filler film; 631. First filler portion; 632. Second filler portion; 64. Adhesive film; 7. Second cover plate. Detailed Implementation
[0038] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this disclosure.
[0039] The second encapsulation layer of a photovoltaic module provided in this disclosure has a first thickness corresponding to the gap between adjacent cells, a second thickness corresponding to the gap between the cells and the frame, and a third thickness corresponding to the cells. By setting the first and second thicknesses to be greater than the third thickness, only the portions of the second encapsulation layer corresponding to the first and second gaps are thickened. This allows the material of the thickened portion of the second encapsulation layer corresponding to the first gap to fill the first gap during lamination, and the material of the thickened portion of the second encapsulation layer corresponding to the second gap to fill the second gap during lamination. The second encapsulation layer does not need to be thickened overall, which can reduce the thickness design of the portions of the second encapsulation layer that do not correspond to the first and second gaps. The third thickness of the second encapsulation layer can be set to 180-380 micrometers. Compared with the encapsulation layer thickness of conventional photovoltaic modules, the amount of material used in the second encapsulation layer is reduced, thereby reducing the production cost of the photovoltaic module, while achieving good encapsulation performance of the second encapsulation layer.
[0040] Please refer to Figures 1-2. This embodiment of the present disclosure provides a photovoltaic module, including a frame 1 and a laminate 2 fixed within the frame 1. The laminate 2 includes a first cover plate 3, a first encapsulation layer 4, a cell layer 5, a second encapsulation layer 6, and a second cover plate 7 stacked sequentially. The cell layer 5 includes a plurality of cells 51, with a first gap 52 between adjacent cells 51 and a second gap 53 between the cells 51 at the edge of the cell layer 5 and the frame 1.
[0041] The portion of the second encapsulation layer 6 corresponding to the first gap 52 has a first thickness D1, the portion of the second encapsulation layer 6 corresponding to the second gap 53 has a second thickness D2, and the portion of the second encapsulation layer 6 corresponding to the battery cell 51 has a third thickness D3. The third thickness D3 is 180 to 380 micrometers, and both the first thickness D1 and the second thickness D2 are greater than the third thickness D3.
[0042] In this embodiment, the first cover plate 3 and the second cover plate 7 are not clearly distinguished, nor are the first encapsulation layer 4 and the second encapsulation layer 6. Specifically, one of the first cover plate 3 and the second cover plate 7 is the front cover plate, and the other is the rear cover plate; one of the first encapsulation layer 4 and the second encapsulation layer 6 is the front encapsulating film, and the other is the rear encapsulating film. One of the first cover plate 3 and the second cover plate 7 is located on the solar-shielded surface of the photovoltaic module, and the other is located on the solar-backed surface of the photovoltaic module.
[0043] When the second cover plate 7 is the front cover plate, it is located on the solar-shielded surface of the photovoltaic module, and the first cover plate 3 is the rear cover plate, located on the solar-shielded back surface of the photovoltaic module. In this case, the first encapsulation layer 4 is the rear encapsulation film, and the second encapsulation layer 6 is the front encapsulation film. When the first cover plate 3 is the front cover plate, it is located on the solar-shielded surface of the photovoltaic module, and the second cover plate 7 is the rear cover plate, located on the solar-shielded back surface of the photovoltaic module. In this case, the first encapsulation layer 4 is the front encapsulation film, and the second encapsulation layer 6 is the rear encapsulation film.
[0044] The photovoltaic module can be a double-glass module or a single-glass module. When the photovoltaic module is a double-glass module, both the first cover plate 3 and the second cover plate 7 are transparent glass. When the photovoltaic module is a single-glass module, one of the first cover plate 3 and the second cover plate 7 is transparent glass, and the other is a back sheet. For example, the first cover plate 3 is transparent glass, and the second cover plate 7 is a back sheet.
[0045] In this embodiment of the present disclosure, the second encapsulation layer 6 of a photovoltaic module has a first thickness D1 corresponding to the first gap 52, a second thickness D2 corresponding to the second gap 53, and a third thickness D3 corresponding to the cell 51. By setting the first thickness D1 and the second thickness D2 to be greater than the third thickness D3, only the portions of the second encapsulation layer 6 corresponding to the first gap 52 and the second gap 53 are thickened. This allows the material of the thickened portion of the second encapsulation layer 6 corresponding to the first gap 52 to fill the first gap 52 during lamination, and the material of the thickened portion of the second encapsulation layer 6 corresponding to the second gap 53 to fill the second gap 53 during lamination. The second encapsulation layer 6 does not need to be thickened overall, reducing the thickness design of the area of the second encapsulation layer 6 other than those corresponding to the first gap 52 and the second gap 53. The third thickness D3 of the second encapsulation layer 6 can be set to 180–380 micrometers. Compared to the encapsulation layer thickness of conventional photovoltaic modules, this reduces the material usage of the second encapsulation layer 6, thereby reducing the production cost of the photovoltaic module, while simultaneously achieving good encapsulation performance of the second encapsulation layer 6. The thickening of the portion of the second encapsulation layer 6 corresponding to the first gap 52 and the portion corresponding to the second gap 53 can be achieved by using an additional filling film for thickening, or by directly designing the portion of the second encapsulation layer 6 corresponding to the first gap 52 and the portion corresponding to the second gap 53 to be thicker.
[0046] In a specific embodiment, the first encapsulation layer 4 may have a first thickness D1 corresponding to the portion of the first gap 52, a second thickness D2 corresponding to the portion of the second gap 53, and a third thickness D3 corresponding to the portion of the battery cell 51. The third thickness D3 is 180–380 micrometers, and both the first thickness D1 and the second thickness D2 are greater than the third thickness D3. That is, the structure and thickness of the second encapsulation layer 6 and the first encapsulation layer 4 may be the same. Of course, the first encapsulation layer 4 may also adopt an existing conventional thickness encapsulation layer.
[0047] In this embodiment of the disclosure, the first encapsulation layer 4 and the second encapsulation layer 6 are located on the first and second sides of the cell layer 5, respectively. The first encapsulation layer 4 and the second encapsulation layer 6 are used to encapsulate the cell layer 5. Their main function is to protect the cell layer 5, prevent water and oxygen from entering and causing the cell 51 in the cell layer 5 to fail, and encapsulate it into a photovoltaic module that can output DC power.
[0048] In this embodiment, the specific thicknesses of the first thickness D1 and the second thickness D2 are not limited, and the difference between the first thickness D1, the second thickness D2 and the third thickness D3 is not specifically limited. The thicknesses of the first thickness D1 and the second thickness D2 may be equal or unequal.
[0049] In a preferred embodiment of this disclosure, the third thickness D3 is 200-250 micrometers.
[0050] In this embodiment, the third thickness D3 is set to 200-250 micrometers, which can achieve good encapsulation of the battery cell area by the second encapsulation layer 6 and greatly reduce the amount of material used in the second encapsulation layer 6, thereby greatly reducing the cost.
[0051] In a preferred embodiment of this disclosure, the ratio of the thickness of the first thickness D1 and the second thickness D2 to the thickness of the third thickness D3 is 1.2 to 3.
[0052] In this embodiment, the ratio of the first thickness D1 to the third thickness D3 and the ratio of the second thickness D2 to the third thickness D3 are both 1.2 to 3. By reasonably setting the difference between the thicknesses of the first thickness D1 and the second thickness D2 and the third thickness D3, a good encapsulation effect can be achieved in each region of the first encapsulation layer, and the material usage of the second encapsulation layer 6 can be greatly reduced, thereby significantly reducing costs. More preferably, the ratio of the thicknesses of the first thickness D1 and the second thickness D2 to the third thickness D3 is 1.2 to 2.
[0053] In a preferred embodiment of this disclosure, the first thickness D1 and the second thickness D2 are greater than 300 micrometers.
[0054] In this embodiment, the first thickness D1 and the second thickness D2 are greater than 300 micrometers, which can better achieve the encapsulation of the first gap 52 region and the second gap 53 region.
[0055] In this embodiment of the disclosure, the number of battery cells 51 included in the battery cell layer 5 is not limited. The multiple battery cells 51 of the battery cell layer 5 are laid flat between the first encapsulation layer 4 and the second encapsulation layer 6. The multiple batteries of the battery cell layer 5 can be arranged in one of the following ways: series connection, parallel connection, series connection and parallel connection.
[0056] In this embodiment, the first gap 52 can be the gap between adjacent battery cells 51 between battery strings, or the gap between adjacent battery cells 51 within the same battery string. The gap between adjacent battery cells 51 between battery strings and the gap between adjacent battery cells 51 within the same battery string can be equal or unequal. For example, the gap between adjacent battery cells 51 between battery strings is 0.5–2.5 mm, and the gap between adjacent battery cells 51 within the same battery string is 0.5–1.5 mm; that is, the width of the first gap 52 is 0.5–2.5 mm. A second gap 53 exists between the battery cells 51 at the edge of the battery cell layer 5 and the frame 1, and the width of the second gap 53 is 7–20 mm.
[0057] As an embodiment of this disclosure, the cell layer 5 includes at least one cell string, and the cells 51 in each cell string are connected by solder strips (not shown).
[0058] The number of battery strings included in the battery cell layer 5 is unlimited, and the battery strings can be connected in series or in parallel via busbars. The battery cell layer 5 includes at least one battery string, and the specific number of battery cells 51 within each battery string is also unlimited. The battery strings are arranged sequentially along a first direction, and the battery cells 51 within each battery string are arranged sequentially along a second direction, with the first and second directions perpendicular. For example, the battery cell layer 5 may include 6 battery strings, and each battery string contains 9 battery cells 51.
[0059] In a preferred embodiment of this disclosure, the solder strip is specifically a flat solder strip. The flat solder strip has a square cross-section and is in planar contact with the battery cell, thus there is almost no gap between the flat solder strip and the surface of the battery cell 51.
[0060] In related technologies, since the solar cells 51 are connected by circular solder ribbons, there are gaps between the circular solder ribbons and the solar cells 51. This causes the encapsulation layer to thin after lamination in the solder ribbon area, affecting the encapsulation performance. Moreover, the thickness of the encapsulation layer is uneven around the solder ribbon after lamination, which easily leads to air bubbles and low production yield. In this embodiment, since the solar cells 51 are connected by flat solder ribbons, there are almost no gaps between the flat solder ribbons and the surface of the solar cells 51. The area corresponding to the flat solder ribbon after lamination of the first encapsulation layer 4 or the second encapsulation layer 6 will not be thinned. Therefore, the first encapsulation layer 4 in this embodiment does not need to be thickened or filled with adhesive strips in the area corresponding to the flat solder ribbon, or the second encapsulation layer 6 does not need to be thickened or filled with adhesive strips in the area corresponding to the flat solder ribbon. This can reduce the material usage of the encapsulation layer, reduce costs, and simplify the process. At the same time, it can make the thickness of the first encapsulation layer 4 or the second encapsulation layer 6 more uniform around the solder ribbon, making it less prone to air bubbles, thereby improving the production yield of photovoltaic modules.
[0061] As one embodiment of this disclosure, the thickness of the solder strip is 0.07–0.3 mm, and the width is 0.5–3 mm. Preferably, the solder strip is a flat solder strip.
[0062] For example, the thickness of the flat solder strip can be any value among 0.07 mm, 0.08 mm, 0.1 mm, 0.12 mm, 0.15 mm, 0.17 mm, 0.18 mm, 0.2 mm, 0.4 mm, 0.6 mm, 0.25 mm, 0.27 mm, 0.29 mm, and 0.3 mm; for example, the width of the flat solder strip can be any value among 0.5 mm, 0.6 mm, 0.65 mm, 0.8 mm, 0.9 mm, 1.1 mm, 1.5 mm, 1.6 mm, 1.8 mm, 2.0 mm, 2.2 mm, 2.5 mm, 2.7 mm, 2.8 mm, and 3.0 mm.
[0063] In this embodiment, the thickness of the flat solder strip is controlled to be 0.07-0.3 mm and the width to be 0.5-3 mm. This not only achieves good conductivity of the flat solder strip, but also reduces the material usage of the first encapsulation layer 4 and the second encapsulation layer 6, thus reducing costs. Furthermore, after lamination, the thickness of the first encapsulation layer 4 and the second encapsulation layer 6 is more uniform around the solder strip, making it less prone to air bubbles.
[0064] As one embodiment of this disclosure, the area of the second encapsulation layer 6 near the second cover plate 7 corresponding to the flat solder strip is planar, or the area of the second encapsulation layer 6 near the second cover plate 7 corresponding to the flat solder strip protrudes toward the second cover plate 7.
[0065] In this embodiment, the area of the second encapsulation layer 6 near the second cover plate 7 corresponding to the first gap 52 can be planar or protruding towards the second cover plate 7 to form a protrusion.
[0066] In related technologies, during the lamination process of photovoltaic modules, after the encapsulation layer melts, some of the encapsulation layer material enters the gap between the solder ribbon and the cell 51, causing the encapsulation layer to thin at the corresponding solder ribbon position and resulting in local depression, which affects the encapsulation performance of the encapsulation layer. In this disclosure, since a flat solder ribbon is used instead of a circular solder ribbon, the encapsulation layer at the corresponding solder ribbon position will not thin during the lamination process of the photovoltaic module, and therefore will not affect the encapsulation performance of the cell 51. This will ensure that the surface of the second encapsulation layer 6 near the second cover plate 7 remains flat or protrudes towards the second cover plate 7 to form a protrusion, maintaining the good encapsulation performance of the second encapsulation layer 6. Moreover, there is no need to pre-thicken the thickness of the second encapsulation layer 6 at the corresponding flat solder ribbon position, which can reduce production costs and simplify the production process.
[0067] Please refer to Figure 1. As an embodiment of this disclosure, the surface of the second encapsulation layer 6 near the second cover plate 7 is planar in the area corresponding to the first gap 52.
[0068] In this embodiment, when the volume of the material thickened in the second encapsulation layer 6 corresponding to the first gap 52 is equal to the volume of the first gap 52, the area of the second encapsulation layer 6 near the second cover plate 7 corresponding to the first gap 52 is planar, which can satisfy that the first thickness D1 is greater than the third thickness D3, thus achieving good encapsulation performance. Furthermore, since the area of the second encapsulation layer 6 corresponding to the first gap 52 is in planar contact with the second cover plate 7, the second encapsulation layer 6 and the second cover plate 7 are subjected to more uniform force, which is beneficial to improving the overall structural stability of the photovoltaic module.
[0069] Referring to Figure 2, as another embodiment of this disclosure, the surface of the second encapsulation layer 6 near the second cover plate 7 protrudes in the direction of the second cover plate 7 to form a first protrusion 61 corresponding to the area of the first gap 52.
[0070] In this embodiment, when the volume of the thickened material in the portion of the second encapsulation layer 6 corresponding to the first gap 52 is greater than the volume of the first gap 52, the area of the second encapsulation layer 6 near the second cover plate 7 corresponding to the first gap 52 protrudes towards the second plate to form a first protrusion 61. This satisfies the requirement that the first thickness D1 is greater than the third thickness D3, and further increases the thickness of the portion of the second encapsulation layer 6 corresponding to the first gap 52, thereby further improving the encapsulation performance of the second encapsulation layer 6. Moreover, the presence of the first protrusion 61 increases the bonding force between the second encapsulation layer 6 and the second cover plate 7 after lamination, thereby improving the structural strength of the photovoltaic module and extending its service life. The first protrusion 61 can be an arc-shaped protrusion or a square protrusion. Preferably, the first protrusion 61 is an arc-shaped protrusion to reduce the concentrated stress in the first protrusion 61.
[0071] The height of the first protrusion 61 is not specifically limited and can be determined by the volume of the thickened material of the second encapsulation layer 6 corresponding to the first gap 52.
[0072] Please refer to Figure 1. As an embodiment of this disclosure, the surface of the second encapsulation layer 6 near the second cover plate 7 is planar in the area corresponding to the second gap 53.
[0073] In this embodiment, when the volume of the material thickened in the second encapsulation layer 6 corresponding to the second gap 53 is equal to the volume of the second gap 53, the area of the second encapsulation layer 6 near the second cover plate 7 corresponding to the second gap 53 is planar, which can satisfy that the second thickness D2 is greater than the third thickness D3, thus achieving good encapsulation performance. Furthermore, since the area of the second encapsulation layer 6 corresponding to the second gap 53 is in planar contact with the second cover plate 7, the second encapsulation layer 6 and the second cover plate 7 are subjected to more uniform force, which is beneficial to improving the overall structural stability of the photovoltaic module.
[0074] Please refer to Figure 2. As an embodiment of this disclosure, the second encapsulation layer 6 protrudes towards the second cover plate 7 in the area corresponding to the second gap 53 to form a second protrusion 62.
[0075] In this embodiment, when the volume of the thickened material in the portion of the second encapsulation layer 6 corresponding to the second gap 53 is greater than the volume of the second gap 53, the area of the second encapsulation layer 6 near the second cover plate 7 corresponding to the second gap 53 protrudes towards the second plate to form a second protrusion 62. This satisfies the requirement that the second thickness D2 is greater than the third thickness D3, and further increases the thickness of the portion of the second encapsulation layer 6 corresponding to the second gap 53, thereby further improving the encapsulation performance of the second encapsulation layer 6. Moreover, the presence of the second protrusion 62 also increases the bonding force between the second encapsulation layer 6 and the second cover plate 7 after lamination, thereby improving the structural strength of the photovoltaic module and extending its service life. The second protrusion 62 can be an arc-shaped protrusion or a square protrusion. Preferably, the second protrusion 62 is also an arc-shaped protrusion.
[0076] The height of the second protrusion 62 is not specifically limited and can be determined by the volume of the thickened material of the second encapsulation layer 6 corresponding to the second gap 53.
[0077] Please refer to Figures 3-6. As an embodiment of this disclosure, the second encapsulation layer 6 includes an adhesive film 64 and a filler film 63. The filler film 63 is disposed between the second cover plate 7 and the adhesive film 64, or the filler film 63 is disposed between the adhesive film 64 and the battery cell layer 5. The filler film 63 includes a first filling portion 631 corresponding to the position of the first gap 52 and a second filling portion 632 corresponding to the second gap 53.
[0078] In this embodiment, the second encapsulation layer 6 is composed of an adhesive film 64 and a filler film 63. The number and position of the first filler portions 631 correspond to the number and position of the first gaps 52, and the number and position of the second filler portions 632 correspond to the number and position of the second gaps 53. Preferably, as shown in Figures 5 and 6, the first filler portions 631 and the second filler portions 632 are specifically elongated strips, and the filler film 63 is generally a mesh film. Figure 5 is a schematic diagram of a filler film for a photovoltaic module provided in this embodiment, and Figure 6 is a cross-sectional schematic diagram along the AA direction in Figure 5.
[0079] Before laminating the photovoltaic module, the filler film 63 can be placed between the second cover plate 7 and the encapsulant film 64, or the filler film 63 can be placed between the encapsulant film 64 and the cell layer 5; or the filler film 63 can be placed between the encapsulant film 64 and the cell layer 5 while the filler film 63 is placed between the second cover plate 7 and the encapsulant film 64. After the filler film 63 is placed, the first filling part 631 of the filler film 63 corresponds to the position of the first gap 52, and the second filling part 632 of the filler film 63 corresponds to the position of the second gap 53.
[0080] As shown in Figure 3, when the filler film 63 is placed between the encapsulant film 64 and the cell layer 5, during the lamination process of the photovoltaic module, after the material of the first filler part 631 melts, part or all of the material of the first filler part 631 fills into the first gap 52. After the material of the second filler part 632 melts, part or all of the material of the second filler part 632 fills into the second gap 53. Since the first filler part 631 can fill the first gap 52 and the second filler part 632 can fill the second gap 53, the material melted by the encapsulant film 64 will not fill into the first gap 52 and the second gap 53. Therefore, the second encapsulation layer 6 will not be thinned in the first gap 52 and the second gap 53, thus achieving good cell encapsulation performance of the encapsulant film.
[0081] As shown in Figure 4, when the filler film 63 is placed between the second cover plate 7 and the adhesive film 64, during the lamination process of the photovoltaic module, after the adhesive film 64 melts, some of the adhesive film 64 will fill into the first gap 52. The melting of the first filler portion 631 can compensate for the adhesive film 64 material entering the first gap 52, thus preventing the second encapsulation layer 6 from experiencing a depression in the area corresponding to the first gap 52, allowing the area of the second encapsulation layer 6 corresponding to the first gap 52 to still maintain good encapsulation performance. Similarly, during the lamination process of the photovoltaic module, after the adhesive film 64 melts, some of the adhesive film 64 will fill into the second gap 53. The melting of the second filler portion 632 can compensate for the adhesive film 64 material entering the second gap 53, thus preventing the second encapsulation layer 6 from experiencing a depression in the area corresponding to the second gap 53, allowing the area of the second encapsulation layer 6 corresponding to the second gap 53 to also maintain good encapsulation performance.
[0082] Therefore, since the filler film 63 fills the first gap 52 and the second gap 53, a thinner adhesive film 64 can be selected to encapsulate the battery cell layer 5. The required thickness of the adhesive film 64 is the third thickness D3. The adhesive film 64 can be set to 180-380 micrometers, while the conventional adhesive film 64 needs to be at least 400 micrometers. Therefore, the thickness design of the adhesive film 64 can be reduced, the amount of material used can be reduced, thereby reducing the cost, while maintaining the good encapsulation performance of the adhesive film 64. Moreover, it is only necessary to place the corresponding filler film 63 before lamination, making the process very simple and the cost low.
[0083] As one embodiment of this disclosure, the filler film 63 and the adhesive film 64 are an integral structure.
[0084] In this embodiment, the filler film 63 and the adhesive film 64 can be integrally formed to form the first encapsulation layer 4. Before lamination, the second encapsulation layer 6 can be placed between the second cover plate 7 and the battery cell layer 5 at one time, which can improve production efficiency.
[0085] In another embodiment of this disclosure, the filler film 63 and the adhesive film 64 are separate structures.
[0086] In this embodiment, the filler film 63 and the adhesive film 64 can be separate structures. Before lamination, the filler film 63 can be placed separately between the second cover plate 7 and the adhesive film 64 or between the adhesive film 64 and the battery cell layer 5. This facilitates the separate preparation of the filler film 63 and the adhesive film 64, reduces production costs, and lowers the difficulty of the production process of the filler film 63 and the adhesive film 64. Moreover, it also allows for flexible replacement of the placement position of the filler film 63 according to actual needs.
[0087] As one embodiment of this disclosure, the filler film 63 is bonded between the second cover plate 7 and the adhesive film 64, or the filler film 63 is bonded between the adhesive film 64 and the battery cell layer 5.
[0088] In this embodiment, the filler film 63 is bonded between the second cover plate 7 and the adhesive film 64, or between the adhesive film 64 and the battery cell layer 5. This prevents the filler film 63 from shifting during lamination and improves the reliability of filling the first gap 52 and the second gap 53. When the filler film 63 is disposed between the second cover plate 7 and the adhesive film 64, the filler film 63 is fixed to the side of the second cover plate 7 near the adhesive film 64 by thermal bonding, or it can be thermally bonded to the side of the adhesive film 64 near the second cover plate 7. When the filler film 63 is disposed between the adhesive film 64 and the battery cell layer 5, the filler film 63 can be thermally bonded to the side of the adhesive film 64 near the battery cell layer 5, or it can be thermally bonded to the side of the battery cell layer 5 near the adhesive film 64. Of course, the filler film 63 can also be placed directly between the second cover plate 7 and the adhesive film 64, or the filler film 63 can be placed between the adhesive film 64 and the battery cell layer 5.
[0089] As one embodiment of this disclosure, the width of the first filling portion 631 is greater than the width of the first gap 52.
[0090] In this embodiment, the width of the first filling portion 631 is greater than the width of the first gap 52, which allows the first filling portion 631 to fill the first gap 52 as much as possible, improving the filling effect of the first filling portion 631, and also making it easier for the first filling portion 631 to overlap and be placed on top of the battery cell 51. The specific difference between the width of the first filling portion 631 and the width of the first gap 52 can be determined according to the actual design and is not limited here.
[0091] As one embodiment of this disclosure, the width of the second filling portion 632 is greater than the width of the second gap 53.
[0092] In this embodiment, the width of the second filling portion 632 is greater than the width of the second gap 53, which allows the second filling portion 632 to fill the second gap 53 as much as possible, thereby improving the filling effect of the first filling film 63. The specific difference between the width of the second filling portion 632 and the width of the second gap 53 can be determined according to actual design and is not limited here.
[0093] As an embodiment of this disclosure, the thickness of both the first filling portion 631 and the second filling portion 632 is 80 to 400 micrometers.
[0094] In this embodiment, the thickness of the first filling part 631 and the second filling part 632 is set to 80 to 400 micrometers, which can make the first filling part 631 fill the first gap 52 as much as possible, and the first filling part 631 fill the second gap 53 as much as possible, thereby improving the filling effect of the first filling part 631 and the second filling part 632.
[0095] Further preferably, the thickness of the first filling portion 631 and the second filling portion 632 is 200-250 micrometers, which can improve the filling effect of the first filling portion 631 and the second filling portion 632 and achieve lower production costs. Preferably, the thickness of the first filling portion 631 and the second filling portion 632 is the same, which facilitates the one-time processing and forming of the filling film 63.
[0096] In this embodiment of the disclosure, the materials of the filler film 63 and the adhesive film 64 may be the same or different.
[0097] As an embodiment of this disclosure, the filler film 63 and the adhesive film 64 are made of the same material, but the pre-crosslinking degree of the filler film 63 is greater than that of the adhesive film 64.
[0098] In this embodiment, the pre-crosslinking degree of the filler film 63 is set to be greater than that of the adhesive film 64, which can reduce the flowability of the filler film 63. During the lamination process, the first filling part 631 of the filler film 63 can fill the first gap 52 well, and the second filling part 632 of the filler film 63 can fill the second gap 53 well. This can prevent the first filling part 631 and the second filling part 632 from flowing to other areas as much as possible, thereby better achieving the pre-filling effect of the filler film 63.
[0099] The filler film 63 and the adhesive film 64 can be one or a combination of EVA (ethylene vinyl acetate copolymer), POE (polymer of ethylene and butene), EPE (EVA-POE-EVA three-layer co-extruded film), EE (EVA-EVA two-layer co-extruded film), and PE (PET-EVA two-layer backsheet film). PET (Polyethylene Terephthalate) refers to polyethylene terephthalate.
[0100] As an embodiment of this disclosure, the pre-crosslinking degree of the filler film 63 and the adhesive film 64 is 0 to 60%.
[0101] In this embodiment, the pre-crosslinking degree of the filler film 63 and the adhesive film 64 is 0-60%, which can better control the flow properties of the filler film 63 and the adhesive film 64 during the lamination process, achieving a good encapsulation effect of the filler film 63 and the adhesive film 64, and preventing the battery cell 51 from shifting during the lamination process. The pre-crosslinking degree of the filler film 63 and the adhesive film 64 can be the same or different. For example, the pre-crosslinking degree of the filler film 63 and the adhesive film 64 can be any value among 1%, 2%, 5%, 10%, 12%, 20%, 26%, 28%, 30%, 36%, 39%, 40%, 46%, 50%, 55%, and 60%. More preferably, the pre-crosslinking degree of the filler film 63 and the adhesive film 64 is 5%-60%.
[0102] The pre-crosslinking degree of the filler film 63 is greater than that of the adhesive film 64. The pre-crosslinking degree of both the filler film 63 and the adhesive film 64 ranges from 0% to 60%, requiring only that the pre-crosslinking degree of the filler film 63 is greater than that of the adhesive film 64. For example, the pre-crosslinking degree of the filler film 63 is 30%, and the pre-crosslinking degree of the adhesive film 64 is 2%; or, for another example, the pre-crosslinking degree of the filler film 63 is 50%, and the pre-crosslinking degree of the adhesive film 64 is 10%.
[0103] As an embodiment of this disclosure, the ratio of the pre-crosslinking degree of the filler film 63 to the pre-crosslinking degree of the adhesive film 64 is 5 to 30.
[0104] In this embodiment, the ratio of the pre-crosslinking degree of the filler film 63 to the pre-crosslinking degree of the adhesive film 64 is controlled between 5 and 10, so that the pre-crosslinking degree of the filler film 63 and the pre-crosslinking degree of the adhesive film 64 maintain a suitable difference. This can prevent the first filler portion 631 and the second filler portion 632 from flowing to other areas, better achieve the pre-filling effect of the filler film 63, and facilitate the processing and production of the filler film 63 and the adhesive film 64.
[0105] In another embodiment of this disclosure, the filler film 63 and the adhesive film 64 are made of different materials, which makes it easier to select different materials according to the flowability difference between the filler film 63 and the adhesive film 64, thereby reducing the implementation cost.
[0106] For example, the filler film 63 is made of EVA and the adhesive film 64 is made of EPE. By using this material combination, the pre-crosslinking degree of the filler film 63 and the pre-crosslinking degree of the adhesive film 64 can be kept at a suitable difference. This can reduce the flow performance of the first filler portion 631 and the second filler portion 632 to other areas, better achieve the pre-filling effect of the filler film 63, and facilitate the processing and production of the filler film 63 and the adhesive film 64.
[0107] For example, the filler film 63 is made of POE and the adhesive film 64 is made of EE. By using this material combination, the pre-crosslinking degree of the filler film 63 and the pre-crosslinking degree of the adhesive film 64 are kept at a suitable difference, which can reduce the flow performance of the first filler portion 631 and the second filler portion 632 to other areas, and facilitate the processing and production of the filler film 63 and the adhesive film 64.
[0108] This disclosure also provides a photovoltaic power generation system, which includes the photovoltaic modules described in the above embodiments. It should be noted that this photovoltaic power generation system has the same or similar beneficial effects as the photovoltaic modules described above, and the related aspects between the two can be referred to each other; to avoid repetition, they will not be repeated here.
[0109] In this embodiment, the photovoltaic power generation system can be applied in photovoltaic power plants, such as ground-mounted power plants, rooftop power plants, and floating power plants. It can also be applied to equipment or devices that utilize solar energy to generate electricity, such as user solar power supplies, solar streetlights, solar cars, and solar buildings. Of course, it is understood that the application scenarios of the photovoltaic power generation system are not limited to these; that is, the photovoltaic power generation system can be applied in all fields that require solar energy for power generation. Taking a photovoltaic power generation system network as an example, the photovoltaic power generation system may include a photovoltaic array, a combiner box, and an inverter. The photovoltaic array may be an array combination of multiple photovoltaic modules; for example, multiple photovoltaic modules can form multiple photovoltaic arrays. The photovoltaic array is connected to the combiner box, which can collect the current generated by the photovoltaic array. The collected current flows through the inverter and is converted into AC power required by the mains power grid before being connected to the mains power grid to achieve solar power supply.
[0110] The above are merely preferred embodiments of this disclosure and are not intended to limit this disclosure. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.
Claims
1. A photovoltaic module, comprising a frame and a laminate fixed within the frame, the laminate comprising a first cover plate, a first encapsulation layer, a cell layer, a second encapsulation layer, and a second cover plate stacked sequentially; the cell layer comprising a plurality of cells, with a first gap between adjacent cells, and a second gap between the cells at the edge of the cell layer and the frame; The second encapsulation layer has a first thickness at the portion corresponding to the first gap, a second thickness at the portion corresponding to the second gap, and a third thickness at the portion corresponding to the battery cell. The third thickness is 180 to 380 micrometers, and both the first thickness and the second thickness are greater than the third thickness.
2. The photovoltaic module according to claim 1, wherein, The cell layer includes at least one cell string, and the cells within each cell string are connected by solder strips.
3. The photovoltaic module according to claim 2, wherein, The thickness of the welding strip is 0.07–0.3 mm, and the width is 0.5–3 mm.
4. The photovoltaic module according to claim 2, wherein, The second encapsulation layer is planar on the surface near the second cover plate corresponding to the solder strip, or the second encapsulation layer is convex towards the second cover plate on the surface near the second cover plate corresponding to the solder strip.
5. The photovoltaic module according to claim 1, wherein, The second encapsulation layer is planar in the area of the first gap on the surface near the second cover plate; or, the area of the second encapsulation layer near the second cover plate protrudes towards the second cover plate to form a first protrusion.
6. The photovoltaic module according to claim 1, wherein, The area of the second encapsulation layer near the second cover plate corresponding to the second gap is planar; or, the area of the second encapsulation layer near the second cover plate corresponding to the second gap protrudes towards the second cover plate to form the second protrusion.
7. The photovoltaic module according to claim 1, wherein, The second encapsulation layer includes an adhesive film and a filler film, wherein the filler film is disposed between the second cover plate and the adhesive film; or, the filler film is disposed between the adhesive film and the battery cell layer; the filler film includes a first filling portion corresponding to the first gap position and a second filling portion corresponding to the second gap.
8. The photovoltaic module according to claim 7, wherein, The filler film and the adhesive film are an integral structure.
9. The photovoltaic module according to claim 7, wherein, The filler film and the adhesive film are separate structures.
10. The photovoltaic module according to claim 7, wherein, The filler film is bonded between the second cover plate and the adhesive film, or the filler film is bonded between the adhesive film and the battery cell layer.
11. The photovoltaic module according to claim 7, wherein, The width of the first filling portion is greater than the width of the first gap.
12. The photovoltaic module according to claim 7, wherein, The width of the second filling portion is greater than the width of the second gap.
13. The photovoltaic module according to claim 7, wherein, The thickness of both the first filling portion and the second filling portion is 80 to 400 micrometers.
14. The photovoltaic module according to claim 13, wherein, The thickness of both the first filling portion and the second filling portion is 200-250 micrometers.
15. The photovoltaic module according to claim 7, wherein, The filler film is made of the same material as the adhesive film, and the pre-crosslinking degree of the filler film is greater than that of the adhesive film.
16. The photovoltaic module according to claim 15, wherein, The ratio of the pre-crosslinking degree of the filler film to the pre-crosslinking degree of the adhesive film is 5 to 30.
17. The photovoltaic module according to claim 15, wherein, The pre-crosslinking degree of the filler film and the adhesive film is 0-60%.
18. The photovoltaic module according to claim 7, wherein, The filler film is made of a different material than the adhesive film.
19. The photovoltaic module according to claim 1, wherein, The third thickness is 200–250 micrometers.
20. The photovoltaic module according to claim 1, wherein, The ratio of the thickness of the first thickness and the second thickness to the thickness of the third thickness is 1.2 to 3.
21. A photovoltaic power generation system, comprising a photovoltaic module as described in any one of claims 1 to 20.