Power gain photovoltaic module and preparation method thereof

Abstract

The invention relates to the technical field of photovoltaic modules, in particular to a power gain photovoltaic module which structurally comprises front plate glass, a first adhesive film layer, a battery substrate, a gain film layer, a second adhesive film layer and rear plate glass from top to bottom in sequence. The battery substrate comprises a plurality of battery strings, the adjacent battery strings are connected through bus bars, each battery string comprises a plurality of battery pieces, the adjacent battery pieces are connected through welding strips, the gain film layer comprises a reflective bonding layer, and the lower side of the reflective bonding layer is connected with a base material layer. According to the invention, the gain film does not contain a metal material, so that the insulation and voltage resistance risk is very low when the gain film is made into a component, the gain film is closer to a photovoltaic cell, the power improvement effect is better, the material of the gain film can be integrated with the front and rear packaging material layers during lamination, delamination and separation are avoided, and the production efficiency is improved. And the process problem and the later reliability risk generated during assembly packaging are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of photovoltaic components, in particular to a photovoltaic component with a power gain and a preparation method thereof. Background Art

[0002] Solar cells, also known as photovoltaic cells, are semiconductor devices that convert sunlight directly into electrical energy. As they are green and environmentally friendly products that do not cause environmental pollution, and photovoltaics are renewable resources, photovoltaic cells are a new type of battery with broad development prospects.

[0003] In a photovoltaic module, there are multiple photovoltaic cells with gaps between them. When sunlight shines on the gap area, the surface of the substrate in the gap area will reflect part of the sunlight, causing this part of the sunlight to not be used by the photovoltaic cells, thereby reducing the utilization rate of light energy and the photoelectric conversion efficiency of the photovoltaic module.

[0004] In the related art, in order to improve the utilization rate of sunlight and the photoelectric conversion efficiency of photovoltaic modules, a reflective film is set on the back panel of the photovoltaic module and in the gap area corresponding to the photovoltaic cells so that light can reach the photovoltaic cells. However, the reflective layer used in the existing gain film technology mostly uses metal materials to form a concave mirror or convex mirror on the gain film reflective layer to reflect sunlight. This kind of gain film containing metal materials has the risk of insulation withstand voltage after being made into a component, and there is a reliability risk of delamination and separation between the metal material and the component during lamination. Moreover, most gain film products cannot be laid on the upper layer of the post-packaging material and the lower layer of the photovoltaic cell. Due to the complex product structure, the thickness and material are not well controlled, which can easily lead to hidden cracks in the cell after lamination. In addition, due to the barrier of the post-packaging material, the gain effect of the gain film cannot be maximized. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a photovoltaic component with a power gain and a preparation method thereof to solve the above problems.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: a power gain photovoltaic module, the structure of which is, from top to bottom, a front glass plate, a first adhesive film layer, a battery substrate, a gain film layer, a second adhesive film layer, and a rear glass plate; the battery substrate includes a plurality of battery strings, and adjacent battery strings are connected by bus bars, and the battery string includes a plurality of battery cells, and adjacent battery cells are connected by welding strips.

[0007] As a further solution of the present invention, the gain film layer includes a reflective adhesive layer, and a substrate layer is connected to the lower side of the reflective adhesive layer.

[0008] As a further solution of the present invention, the reflective adhesive layer comprises a hot melt adhesive layer, the hot melt adhesive layer is filled with reflective particles, and the reflective adhesive layer is made by pre-crosslinking the hot melt adhesive and the reflective particles.

[0009] As a further solution of the present invention, the pre-crosslinking degree between the hot melt adhesive and the reflective particle portion is 0-40%.

[0010] As a further scheme of the present invention, the reflective particle portion includes but is not limited to first reflective particles, second reflective particles, third reflective particles, fourth reflective particles, fifth reflective particles, sixth reflective particles, seventh reflective particles, eighth reflective particles, ninth reflective particles, tenth reflective particles, eleventh reflective particles, twelfth reflective particles, and thirteenth reflective particles.

[0011] As a further solution of the present invention, the cross-section of the reflective particle portion includes but is not limited to a circle, a triangle, and a pentagon.

[0012] As a further solution of the present invention, the material of the reflective particle portion includes but is not limited to resin material or rare earth or titanium dioxide.

[0013] As a further solution of the present invention, the material of the hot melt adhesive is EVA or POE or EPE.

[0014] As a further solution of the present invention, the gain film layer is a strip-shaped structure with a thickness of 30-100 um.

[0015] As a further solution of the present invention, the color of the gain film layer includes but is not limited to white.

[0016] As a further embodiment of the present invention, the substrate layer is made of modified polyolefin.

[0017] As a further solution of the present invention, the gain film layer is arranged along a direction perpendicular or parallel to the arrangement direction of the battery strings, and is disposed in the gaps between adjacent battery strings.

[0018] As a further solution of the present invention, the gain film layer is segmented and arranged in the gap between adjacent battery strings.

[0019] As a further solution of the present invention, the gain film layer is arranged along a direction perpendicular or parallel to the arrangement direction of the battery strings, and is disposed around the battery substrate.

[0020] A method for preparing a photovoltaic module with a high power gain, the specific steps are as follows: Step 1: Lay a first adhesive film layer on the front glass plate; Step 2: laying a battery string on the first adhesive film layer, with a first gap between battery cells in the battery string and a second gap between adjacent battery strings; Step 3: Lay a gain film layer around the solar cell; Step 4: Lay the second adhesive film layer, and finally lay the rear glass plate; Step five: Send the laid photovoltaic modules to high temperature and high pressure for lamination.

[0021] As a further solution of the present invention, in step three, gain film layers are laid around the first gap, the second gap, the battery cell, and the battery string respectively.

[0022] As a further solution of the present invention, the specific steps of laying the gain film layer in step three are: using a spot temperature device to thermally fix the gain film layer on the first adhesive film layer in the gap between the battery cells at a temperature of 25-40°C.

[0023] As a further solution of the present invention, the specific steps of laying the gain film layer in step three are: using tape or glue to fix the gain film layer on the first adhesive film layer between the battery cells.

[0024] Since the present invention adopts the above technical solution, the advantages and positive effects of the present invention are: the gain film can be made free of metal materials, so the risk of insulation withstand voltage when it is made into a component is very low, and the gain film is closer to the photovoltaic cell, the power boosting effect is better, and the material of the gain film can be integrated with the front and rear packaging material layers during lamination without delamination and separation, thereby reducing the process problems and later reliability risks caused by component packaging. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the structure of a photovoltaic module.

[0026] Figure 2 This is a schematic diagram of the structure of the first gain film layer.

[0027] Figure 3 This is a schematic diagram of the structure of the second gain film layer.

[0028] Figure 4 This is a schematic diagram of the structure of the third gain film layer.

[0029] Figure 5 This is a schematic diagram of the structure of the fourth gain film layer.

[0030] Figure 6 This is a statistical graph showing the relationship between the gain film thickness and the crack rate of the finished photovoltaic module. Figure 7 This is a top view of the front of a photovoltaic module without gain film.

[0031] Figure 8 This is the laying method of Example 1.

[0032] Fig. 9 This is the laying method of Example 2.

[0033] Fig.10 This is the laying method of embodiment 3.

[0034] Fig.11 This is the laying method of embodiment 4.

[0035] Fig.12 It is a flow chart of the photovoltaic module manufacturing of this application.

[0036] In the figure: 1 is the front glass, 2 is the first adhesive film layer, 3 is a battery substrate, 31 is a battery string, 311 is a battery cell, 4 is a gain film layer, 41 is a reflective adhesive layer, 411 is a reflective particle portion, 411a is a first reflective particle, 411b is a second reflective particle, 411c is a third reflective particle, 411d is a fourth reflective particle, 411e is a fifth reflective particle, 411f is a sixth reflective particle, 411g is a seventh reflective particle, 411h is an eighth reflective particle, 411i is a ninth reflective particle, 411j is a tenth reflective particle, 411k is an eleventh reflective particle, 411m is a twelfth reflective particle, 412 is a hot melt adhesive layer, 42 is a substrate layer, 4a is a gain film in the gap between battery strings, 4b is a gain film outside the photovoltaic battery layer, 4c is a gain film in the gap between battery cells, 5 is the second adhesive film layer, 6 is the rear glass plate, A is the laying direction of the vertical battery string, and B is the laying direction of the parallel battery string. DETAILED DESCRIPTION

[0037] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0038] like Figure 1 As shown, the present invention is a photovoltaic module with power gain, and the structure of the photovoltaic module is, from top to bottom, a front glass plate 1, a first adhesive film layer 2, a battery substrate 3, a gain film layer 4, a second adhesive film layer 5, and a rear glass plate 6; the battery substrate 3 includes a plurality of battery strings 31, and the adjacent battery strings 31 are connected by bus bars, and the battery string 31 includes a plurality of battery cells 311, and the adjacent battery cells 311 are connected by welding strips. Compared with the conventional gain film set on the upper layer of the back plate and the lower layer of the second adhesive film layer 5, the present invention adopts the above structure to make the reflective layer closer to the photovoltaic module battery, so that more light energy can be reflected to the front of the battery, and the power generation efficiency is improved. The materials of the front glass plate 1 and the rear glass plate 6 can be replaced by transparent organic polymers.

[0039] The present invention further, as Figure 2As shown, the gain film layer 4 includes a reflective adhesive layer 41, and a substrate layer 42 is connected to the lower side of the reflective adhesive layer 41. The use of a double-layer structure can well reduce the thickness of the gain film and reduce the risk of delamination and separation of the components after manufacturing.

[0040] In the present invention, the reflective adhesive layer 41 includes a hot melt adhesive layer 412, and the hot melt adhesive layer 412 is filled with a reflective particle portion 411. The reflective adhesive layer 41 is made of hot melt adhesive and the reflective particle portion 411 through pre-crosslinking. The hot melt adhesive layer 412 is made of EVA, POE, or EPE. The hot melt adhesive layer 412 is similar to the materials of the first adhesive film layer 2 and the second adhesive film layer 5, and can be better melted to each other during lamination, which can reduce the risk of delamination and bubble generation of the component during lamination.

[0041] In the present invention, the pre-crosslinking degree between the hot melt adhesive and the reflective particle portion 411 is 0-40%, which can be more conveniently operated during the component lamination process.

[0042] The present invention further, as Figure 2-5 As shown, the reflective particle portion 411 includes but is not limited to first reflective particles 411a, second reflective particles 411b, third reflective particles 411c, fourth reflective particles 411d, fifth reflective particles 411e, sixth reflective particles 411f, seventh reflective particles 411g, eighth reflective particles 411h, ninth reflective particles 411i, tenth reflective particles 411j, eleventh reflective particles 411k, twelfth reflective particles 411m, and thirteenth reflective particles 411n; the cross-section of the reflective particle portion 411 includes but is not limited to a circle, a triangle, and a pentagon; the material of the reflective particle portion 411 includes but is not limited to a resin material or rare earth or titanium dioxide. It is preferred to use titanium dioxide of different sizes, and the preferred cross-section is round particles, triangular particles, or pentagonal particles; and after lamination, an irregular reflective surface is formed in the reflective adhesive layer 41, and when sunlight is irradiated on the reflective particle portion 411, it will reflect light at various angles to form diffuse reflection, so that the battery cell 311 can receive light at more incident angles, thereby improving the power generation efficiency of the photovoltaic module, and the material is a non-metallic material, and the risk of insulation withstand voltage is very low after being laminated into a module.

[0043] The present invention further, as Figure 6 As shown, the gain film layer 4 is a strip structure with a thickness of 30-100um. The gain film layer 4 of this thickness allows the gain film layer 4 to overlap when laid. When the gain film thickness exceeds 100um, the risk of hidden cracks in the cell increases. It is preferred to use a thickness of 30-100um to reduce the risk of delamination and separation of the components after manufacturing.

[0044] In the present invention, the color of the gain film layer 4 includes but is not limited to white. The gain effect of white is the most obvious, and different colors of reflective particles 411 can also be selected as required to make differentiated multi-color photovoltaic modules.

[0045] In the present invention, the substrate layer 42 is made of modified polyolefin.

[0046] The present invention further, as Figure 7 As shown, the gain film layer 4 is arranged along the arrangement direction of the battery strings 31 vertically or parallelly, and is arranged in the gaps between adjacent battery strings 31; it is easy to imagine that the gain film layer 4 is arranged in sections in the gaps between adjacent battery strings 31, and it is also easy to imagine that the gain film layer 4 is arranged along the arrangement direction of the battery strings 31 vertically or parallelly, and is arranged around the battery substrate 3. Figure 3 As shown, in the top view of the component without the gain film 4, it can be seen that there are gaps between two adjacent battery strings 31, between two adjacent battery cells 311, and between the outer side of the photovoltaic cell layer 3 and the inner side of the front panel 1. These gaps are areas that cannot be covered by the battery cells 311. If the gain film is not laid, the corresponding areas will not be able to reflect sunlight more efficiently and form a power gain effect.

[0047] Example 1 like Figure 8 As shown, the gain film 4a is arranged vertically or parallel to the arrangement direction of the battery strings 31 and is disposed in the gaps between adjacent battery strings 31. Preferably, the width of the gain film 4a is greater than the gap width between two adjacent battery strings 31.

[0048] Example 2 like Fig. 9 As shown, the gain film 4a is arranged vertically or parallel to the arrangement direction of the battery strings 31 and is disposed in the gaps between the adjacent multiple battery strings 31, and the gain film 4b is arranged vertically in the arrangement direction of the battery strings 31 and is disposed in the gaps between the adjacent multiple battery sheets 311. Preferably, the width of the gain film 4a is greater than the gap width between two adjacent battery strings 31, and the width of the gain film 4b is greater than the gap width between two adjacent battery sheets 311.

[0049] Example 3 like Fig.10As shown, the gain film 4a is arranged vertically or parallel to the arrangement direction of the battery string 31, and is set in the gap between the adjacent multiple battery strings 31, and the gain film 4c is arranged vertically or parallel to the arrangement direction of the battery string 31, and is set in the gap between the adjacent multiple battery strings. The gain film 4c is arranged vertically or parallel to the arrangement direction of the battery string 31, and is set in the gap between the outer side of the photovoltaic cell layer 3 and the inner side of the front plate 1. Preferably, the width of the gain film 4a is greater than the gap width between two adjacent battery strings 31, and the width of the gain film 4c is less than or equal to the width of the gap between the outer side of the photovoltaic cell layer 3 and the inner side of the front plate 1.

[0050] Example 4 like Fig.11 As shown, the gain film 4a is arranged vertically or parallel to the arrangement direction of the battery string 31, and is set in the gap between the adjacent multiple battery strings 31, the gain film 4b is arranged vertically in the arrangement direction of the battery string 31, and the gain film 4c is arranged vertically or parallel to the arrangement direction of the battery string 31, and is set in the gap between the adjacent multiple battery strings 31. The gain film 4c is arranged vertically or parallel to the arrangement direction of the battery string 31, and is set in the gap between the outer side of the photovoltaic cell layer 3 and the inner side of the front plate 1. Preferably, the width of the gain film 4a is greater than the gap width between two adjacent battery strings 31, the width of the gain film 4b is greater than the gap width between two adjacent battery slices 311, and the width of the gain film 4c is less than or equal to the width of the gap between the outer side of the photovoltaic cell layer 3 and the inner side of the front plate 1. This embodiment maximizes the filling of the area that the battery slice 311 cannot cover on the front plate.

[0051] like Fig.12 As shown, a method for preparing a photovoltaic module with a high power gain, the specific steps are as follows: Step 1: firstly lay a first adhesive film layer 2 on the front glass plate 1; Step 2: Then, a battery string 31 is laid on the first adhesive film layer 2, a first gap is set between the battery cells 311 in the battery string 31, and a second gap is set between adjacent battery strings 31; Step 3: laying the gain film layer 4 around the battery cell 311. When laying the gain film layer 4, use a spot temperature device to thermally fix the gain film layer 4 on the first adhesive film layer 2 in the gap between the battery cells 311 at a temperature of 25-40°C; Step 4, laying the second adhesive film layer 5, and finally laying the rear plate glass 6; Step 5: Send the laid photovoltaic modules to high temperature and high pressure for lamination; In step three, the gain film layer 4 is laid around the first gap, the second gap, the battery sheet 311 and the battery string 31 respectively.

[0052] As another method for preparing a photovoltaic module with power gain, the specific steps are as follows: Step 1: firstly lay a first adhesive film layer 2 on the front glass plate 1; Step 2: Then, a battery string 31 is laid on the first adhesive film layer 2, a first gap is set between the battery cells 311 in the battery string 31, and a second gap is set between adjacent battery strings 31; Step three, laying the gain film layer 4 around the battery cell 311. When laying the gain film layer 4, adhesive tape or glue can be used to fix the gain film layer 4 on the battery cell 311 and the first adhesive film layer 2 in the gap between the battery cells 311; Step 4, laying the second adhesive film layer 5, and finally laying the rear plate glass 6; Step 5: Send the laid photovoltaic modules to high temperature and high pressure for lamination; In step three, the gain film layer 4 is laid around the first gap, the second gap, the battery sheet 311 and the battery string 31 respectively.

[0053] Although specific embodiments of the present invention are described above, those skilled in the art should understand that these are merely examples and that various changes or modifications may be made to the embodiments without departing from the principles and essence of the present invention. The scope of protection of the present invention is limited only by the appended claims.

Claims

1. A photovoltaic module with a power gain, characterized by: The structure of the photovoltaic module comprises, from top to bottom, a front glass plate (1), a first adhesive film layer (2), a battery substrate (3), a gain film layer (4), a second adhesive film layer (5), and a rear glass plate (6); the battery substrate (3) comprises a plurality of battery strings (31), adjacent battery strings (31) are connected via a bus bar, and the battery string (31) comprises a plurality of battery cells (311), adjacent battery cells (311) are connected via a welding strip.

2. A photovoltaic module with a power gain according to claim 1, characterized in that: The gain film layer (4) comprises a reflective adhesive layer (41), and a substrate layer (42) is connected to the lower side of the reflective adhesive layer (41).

3. A photovoltaic module with a power gain according to claim 2, characterized in that: The reflective adhesive layer (41) comprises a hot melt adhesive layer (412), the hot melt adhesive layer (412) is filled with a reflective particle portion (411), and the reflective adhesive layer (41) is made by pre-crosslinking the hot melt adhesive and the reflective particle portion (411).

4. A photovoltaic module with a power gain according to claim 3, characterized in that: The pre-crosslinking degree between the hot melt adhesive and the reflective particle portion (411) is 0-40%.

5. The photovoltaic module with a power gain according to claim 3, characterized in that: The reflective particle portion (411) includes but is not limited to first reflective particles (411a), second reflective particles (411b), third reflective particles (411c), fourth reflective particles (411d), fifth reflective particles (411e), sixth reflective particles (411f), seventh reflective particles (411g), eighth reflective particles (411h), ninth reflective particles (411i), tenth reflective particles (411j), eleventh reflective particles (411k), twelfth reflective particles (411m), and thirteenth reflective particles (411n).

6. A photovoltaic module with a power gain according to claim 5, characterized in that: The cross-section of the reflective particle portion (411) includes, but is not limited to, a circle, a triangle, and a pentagon.

7. The photovoltaic module with a power gain according to claim 5, characterized in that: The material of the reflective particle portion (411) includes, but is not limited to, resin material or rare earth or titanium dioxide.

8. The photovoltaic module with a power gain according to claim 3, characterized in that: The material of the hot melt adhesive is EVA, POE or EPE.

9. The photovoltaic module with a power gain according to claim 1, characterized in that: The gain film layer (4) is a strip-shaped structure, and has a thickness of 30-100 um.

10. A photovoltaic module with a power gain according to claim 9, characterized in that: The color of the gain film layer (4) includes but is not limited to white.

11. A photovoltaic module with a power gain according to claim 2, characterized in that: The material of the substrate layer (42) is modified polyolefin.

12. A photovoltaic module with a power gain according to claim 1, characterized in that: The gain film layer (4) is arranged along a vertical or parallel arrangement direction of the battery strings (31), and is disposed in the gap between adjacent battery strings (31).

13. A photovoltaic module with a power gain according to claim 1, characterized in that: The gain film layer (4) is arranged in sections in the gaps between adjacent battery strings (31).

14. The photovoltaic module with a power gain according to claim 1, characterized in that: The gain film layer (4) is arranged along a vertical or parallel arrangement direction of the battery strings (31), and is disposed around the battery substrate (3).

15. A method for preparing a photovoltaic module with high power gain according to any one of claims 1 to 14, characterized in that: Specific steps as follows: Step 1: firstly lay a first adhesive film layer (2) on the front glass plate (1); Step 2: laying a battery string (31) on the first adhesive film layer (2), wherein a first gap is provided between the battery cells (311) in the battery string (31), and a second gap is provided between adjacent battery strings (31); Step three, laying a gain film layer (4) around the battery sheet (311); Step 4, laying the second adhesive film layer (5), and finally laying the rear plate glass (6); Step five: Send the laid photovoltaic modules to high temperature and high pressure for lamination.

16. The method for preparing a photovoltaic module with high power gain according to claim 15, characterized in that: In step three, a gain film layer (4) is laid around the first gap, the second gap, the battery sheet (311), and the battery string (31) respectively.

17. The method for preparing a photovoltaic module with high power gain according to claim 15, characterized in that: The specific steps of laying the gain film layer (4) in step three are: using a spot temperature device to thermally fix the gain film layer (4) on the first adhesive film layer (2) in the gap between the battery cells (311) at a temperature of 25-40°C.

18. The method for preparing a photovoltaic module with high power gain according to claim 15, characterized in that: The specific steps of laying the gain film layer (4) in step three are: using tape or glue to fix the gain film layer (4) on the first adhesive film layer (2) between the battery cells (311) and the battery cells (311).

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