A water-blocking backsheet for a photovoltaic module and a photovoltaic module

Abstract

The utility model discloses a kind of water-blocking back sheet and photovoltaic module for photovoltaic module, it is related to photovoltaic module technical field.The water-blocking back sheet includes: back sheet substrate and the water-blocking film layer of being set to at least one side of back sheet substrate, water-blocking film layer includes at least two first water-blocking film area independent of each other, wherein, each first water-blocking film area at least corresponds one or more cell of photovoltaic module.The water-blocking back sheet can improve the strain resistance of water-blocking film layer, and then improve the water-blocking effect of water-blocking back sheet.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic module technology, and in particular to a water-blocking backsheet for photovoltaic modules and a photovoltaic module. Background Technology

[0002] Photovoltaic (PV) modules are important solar power generation devices that convert solar energy into electrical energy. PV modules are generally made of multiple laminated materials, including cell layers, encapsulant layers, a front panel, and a back panel. The back panel, located on the back side of the PV module, primarily functions as insulation and waterproofing. Existing water-blocking back panels mainly involve depositing a single layer of materials such as silicon oxide or zinc oxide onto the surface of the back panel substrate as a water-blocking film. These water-blocking films have low toughness, and a single layer of water-blocking film is prone to cracking under stress. The shape of these cracks is uncontrollable, increasing the risk of water permeation in the cell area of ​​the back panel and reducing the reliability of the PV module. Utility Model Content

[0003] In view of this, the present invention provides a water-blocking backsheet for photovoltaic modules and a photovoltaic module, which can improve the strain resistance of the water-blocking film layer while improving the water-blocking effect of the backsheet.

[0004] To achieve the above objectives, according to one aspect of the present invention, a water-blocking backsheet for photovoltaic modules is provided, comprising: a backsheet substrate and a water-blocking film layer disposed on at least one side of the backsheet substrate.

[0005] The water-blocking membrane layer includes at least two independent first water-blocking membrane regions, wherein each first water-blocking membrane region corresponds to at least one or more solar cells of the photovoltaic module.

[0006] According to another aspect of the present invention, a photovoltaic module is provided, comprising: a front panel, a front encapsulating film, a cell array, a rear encapsulating film, and the aforementioned water-blocking back panel, which are stacked sequentially.

[0007] One embodiment of the above-mentioned utility model has the following advantages or beneficial effects: it can achieve waterproof effect through a water-blocking membrane layer composed of at least one water-blocking membrane area, and the structure of using multiple water-blocking membrane areas to replace the complete water-blocking membrane layer can improve the stress of the water-blocking membrane layer, reduce the risk of cracking in the battery cell area, improve the waterproof effect and the service life of the water-blocking backplate.

[0008] The further effects of the aforementioned unconventional alternative methods will be explained below in conjunction with specific implementation methods. Attached Figure Description

[0009] The accompanying drawings are provided to better understand this utility model and do not constitute an undue limitation thereof. Wherein:

[0010] Figure 1This is a structural schematic diagram of the water-blocking backplate according to an embodiment of the present utility model;

[0011] Figure 2 This is a schematic diagram of the structure of the first water-blocking membrane region according to an embodiment of the present utility model;

[0012] Figure 3 This is a structural schematic diagram of another water-blocking backplate according to an embodiment of the present utility model;

[0013] Figure 4 This is a schematic diagram of the structure of a water-blocking membrane layer according to an embodiment of the present utility model;

[0014] Figure 5 This is a schematic diagram of the structure of another water-blocking membrane layer according to an embodiment of the present utility model;

[0015] Figure 6 This is a structural schematic diagram of a photovoltaic module according to an embodiment of the present utility model.

[0016] The attached figures are labeled as follows:

[0017] 10 - Backing substrate; 20 - Water-blocking film layer; 201 - First water-blocking film area; 202 - Second water-blocking film area; 30 - First weather-resistant layer; 40 - Second weather-resistant layer; 50 - First weather-resistant adhesive layer; 60 - Second weather-resistant adhesive layer. Detailed Implementation

[0018] The following description, in conjunction with the accompanying drawings, illustrates exemplary embodiments of the present invention, including various details to aid understanding. These embodiments should be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present invention. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.

[0019] In single-glass photovoltaic modules, the main approach to addressing water resistance is to add waterproof materials to the backsheet layer to ensure its ability to block moisture. Suitable waterproof materials include silica and zinc oxide. These materials are deposited onto the substrate surface to form a water-blocking film, resulting in a backsheet water permeability of less than 0.5 g / m². 2 However, these materials are generally brittle and have low toughness, making them prone to cracking under pressure. The crack shapes are randomly generated, and after the photovoltaic module is loaded, the water vapor permeability increases, further increasing the probability of cracking of the water-blocking film. When the crack corresponds to the cell area, it increases the risk of water permeation in the back sheet cell area, reducing the reliability of the photovoltaic module.

[0020] Taking into full account the shortcomings of the above-mentioned technologies, this utility model provides a water-blocking backsheet that can reduce the probability of cracking of the water-blocking film layer and extend the service life of photovoltaic modules.

[0021] Figure 1 , Figures 3 to 5 This is a structural schematic diagram of a water-blocking backsheet according to an embodiment of the present invention, which is applied to photovoltaic modules. Figure 1 , Figures 3 to 5 As shown, the water-blocking backplate includes:

[0022] The back panel substrate 10 and the water-blocking membrane layer 20 disposed on at least one side of the back panel substrate 10.

[0023] The water-blocking membrane layer 20 includes at least two independent first water-blocking membrane regions 201, wherein each first water-blocking membrane region 201 corresponds to at least one or more solar cells of the photovoltaic module.

[0024] The relative positional relationship between the backing substrate 10 and the water-blocking film layer 20 can be such that the water-blocking film layer 20 is provided on one side of the backing substrate 10 or on both sides of the backing substrate 10. Regardless of whether the water-blocking film layer 20 is provided on one side of the backing substrate 10 or on both sides of the backing substrate 10, the water-blocking film layer 20 is provided with at least two first water-blocking film areas 201, that is, the water-blocking film layer 20 includes multiple first water-blocking film areas 201. Each first water-blocking film region 201 is independent of the others. Compared to the existing whole water-blocking film layer, the area of ​​the independent first water-blocking film region 201 is reduced, and its stress resistance is correspondingly improved. Furthermore, adjacent first water-blocking film regions 201 are independent of each other; when one first water-blocking film region 201 is subjected to stress, the stress can only be transmitted to its edge and will not be transmitted to adjacent first water-blocking film regions 201. Even if one first water-blocking film region 201 cracks, it will not affect the use of other first water-blocking film regions 201. Therefore, the strain resistance of the entire water-blocking film layer 20 is improved. The first water-blocking film region 201 corresponds to one or more solar cells of the photovoltaic module, and can correspondingly protect the water resistance of the solar cell area. In contrast, the existing whole water-blocking film layer 20, when subjected to stress, will randomly crack, reducing the water resistance of the solar cell area and lowering the reliability of the photovoltaic module. The size of each first water-blocking film region 201 can be the same or different; that is, each first water-blocking film region 201 can correspond to the same number of solar cells or different numbers of solar cells. In addition, the shapes of each first water-blocking membrane region 201 can be the same or different. That is, when the first water-blocking membrane region 201 corresponds to a battery cell array composed of multiple battery cells, the shape of the first water-blocking membrane region 201 depends on the shape of the battery cell array.

[0025] The relative positional relationship between adjacent first water-blocking membrane regions 201 can be as follows: Figure 2 As shown, adjacent first water-blocking membrane areas 201 are spaced apart by a preset interval value, forming stress relief zones between each first water-blocking membrane area 201 to improve the stress of the water-blocking membrane layer. The edges of two adjacent first water-blocking membrane areas 201 are spaced apart by at least a predetermined distance. For example, this predetermined distance can be 0.8-1.1 mm. If the predetermined distance is less than 0.8 mm, it will increase the difficulty of the cutting process; if the predetermined distance is greater than 1.1 mm, it will increase the probability of water permeability between the gaps and reduce the reliability of the photovoltaic module.

[0026] In another embodiment of the present invention, the relative positional relationship between adjacent first water-blocking membrane areas 201 can also be such that adjacent first water-blocking membrane areas 201 can be arranged with their edges overlapping each other according to a preset overlap distance, so as to improve the strain resistance of the water-blocking membrane layer.

[0027] A portion of the edge of a first water-blocking membrane region 201 overlaps the upper side of the edge of an adjacent portion of the first water-blocking membrane region 201, and another portion of its edge overlaps the lower side of the edge of another adjacent portion of the first water-blocking membrane region 201. Specifically, as... Figure 5 As shown, in the first direction, the upper side of the left edge of a first water-blocking membrane region 201 overlaps the lower side of the right edge of the adjacent first water-blocking membrane region 201 on the left, while the lower side of the right edge overlaps the upper side of the left edge of the adjacent first water-blocking membrane region 201 on the left. When preparing the water-blocking membrane layer 20, it can be prepared sequentially starting from the bottommost first water-blocking membrane region 201, according to the overlapping sequence.

[0028] Alternatively, all edges of one of the first water-blocking membrane regions 201 overlap the upper or lower sides of the edges of all adjacent first water-blocking membrane regions 201. Specifically, as... Figure 4 As shown, in the first direction, the left edge of a first water-blocking membrane region 201 is located above the right edge of the adjacent first water-blocking membrane region 201 on the left, and the right edge is located above the left edge of the adjacent first water-blocking membrane region 201 on the left; or the left edge of a water-blocking membrane region 201 is located below the right edge of the adjacent first water-blocking membrane region 201 on the left, and the right edge is located below the left edge of the adjacent first water-blocking membrane region 201 on the left. Each first water-blocking membrane region 201 can be divided into upper and lower layers. When preparing the water-blocking membrane layer, the lower first water-blocking membrane region 201 can be prepared first, and then the upper first water-blocking membrane region 201 can be prepared.

[0029] In addition, adjacent first water-blocking membranes 201 can be arranged in a combination of spaced-out and edge-overlapping configurations. For example, adjacent first water-blocking membrane areas 201 in the same row in the first direction can be spaced out, while adjacent first water-blocking membrane areas 201 in the same column in the second direction can be edge-overlapping.

[0030] According to the water-blocking backsheet provided by this utility model, the water-blocking membrane layer 20, composed of at least one water-blocking membrane area, can achieve a waterproof effect on the battery cell area. Furthermore, using multiple water-blocking membrane areas instead of a complete water-blocking membrane layer 20 can increase the stress of the water-blocking membrane layer 20, reduce the risk of cracking, and improve the waterproof effect and service life of the water-blocking backsheet. Simultaneously, by pre-setting the stress-relieving area at the edge of the water-blocking membrane area corresponding to the non-battery cell area, the risk of cracking in the battery cell area can be reduced, further improving the waterproof effect of the water-blocking backsheet.

[0031] In one embodiment, a water-blocking film layer 20 is provided on one side of the backplate substrate 10, such as... Figure 1 , Figures 3 to 5 As shown, the water-blocking backplate also includes a first weather-resistant layer 30, a second weather-resistant layer 40, and a first weather-resistant adhesive layer 50. The first weather-resistant adhesive layer 50 and the first weather-resistant layer 30 are stacked from the inside to the outside on the side of the water-blocking film layer 20 away from the backplate substrate 10; the second weather-resistant layer 40 is disposed on the other side of the backplate substrate 10 away from the water-blocking film layer 20.

[0032] like Figure 1 , Figures 4 to 5 As shown, in addition to the water-blocking film layer 20, the water-blocking backsheet 10 also includes a first weather-resistant layer 30, a second weather-resistant layer 40, and a first weather-resistant adhesive layer 50. The first weather-resistant layer 30 and the second weather-resistant layer 40 are respectively disposed on both sides of the backsheet substrate 10, and the first weather-resistant adhesive layer 50 is disposed between the backsheet substrate 10 and the first weather-resistant layer 30. When the water-blocking backsheet is applied to photovoltaic modules, the first weather-resistant layer 30 is disposed on the side away from the solar cells, and the second weather-resistant layer 40 is disposed on the side closer to the solar cells. The second weather-resistant layer 40, the backsheet substrate 10, the water-blocking film layer 20, the first weather-resistant adhesive layer 50, and the first weather-resistant layer 30 are sequentially disposed from the side closest to the solar cells to the side furthest away from the solar cells. The water-blocking film layer 20 disposed in the direction furthest from the solar cells can further improve the water-blocking effect of the water-blocking backsheet.

[0033] According to the water-blocking backplate provided by this utility model, the water-blocking film layer 20 can be encapsulated through the first weather-resistant layer 30, the second weather-resistant layer 40 and the first weather-resistant adhesive layer 50, thereby ensuring the water-blocking effect of the water-blocking backplate.

[0034] In one embodiment, water-resistant film layers 20 are respectively provided on both sides of the backplate substrate 10, such as... Figure 3As shown, the water-blocking backplate also includes a first weather-resistant layer 30, a second weather-resistant layer 40, a first weather-resistant adhesive layer 50, and a second weather-resistant adhesive layer 60. The first weather-resistant adhesive layer 50 and the first weather-resistant layer 30 are stacked from the inside out on the side of the water-blocking film layer 20 of one of the backplate substrates 10 away from the backplate substrate 10. The second weather-resistant adhesive layer 60 and the second weather-resistant layer 40 are stacked from the inside out on the side of the water-blocking film layer 20 of the other backplate substrate 10 away from the backplate substrate 10.

[0035] The waterproof effect of the water-blocking backplate can be further improved by setting water-blocking membrane layers 20 on both sides of the backplate substrate 10. When water-blocking membrane layers 20 are set on both sides, a weather-resistant adhesive layer, namely a second weather-resistant adhesive layer 60, should also be set on the side of the other water-blocking membrane layer 20 away from the backplate substrate 10 to fill the gaps of the water-blocking membrane layer 20 and bond and fix the water-blocking membrane layer 20 and the second weather-resistant layer 40.

[0036] In one embodiment, the water-blocking film layer 20 further includes a second water-blocking film region 202. The second water-blocking film region 202 corresponds to the gap between adjacent cells of the photovoltaic module.

[0037] Based on the first water-blocking film area 201, a second water-blocking film area 202 can be further provided. The second water-blocking film area 202 corresponds to the gap position between adjacent cells in the photovoltaic module. By the cooperation of the second water-blocking film area 202 and the first water-blocking film area 201, the water-blocking effect of the entire photovoltaic module can be improved.

[0038] In one embodiment, the second water-blocking membrane region 202 and the first water-blocking membrane region 201 are located on different sides or the same side of the backplate substrate 10. Specifically, as shown below... Figure 3 As shown, the second water-blocking membrane area 202 is disposed on a different side from the first water-blocking membrane area 201, and the second water-blocking membrane area 202 is disposed corresponding to the gaps in the first water-blocking membrane areas 201. For example, when the first water-blocking membrane area 201 has a square structure, the second water-blocking membrane area 202 is correspondingly a mesh structure. The edges of two adjacent first water-blocking membrane areas 201 can overlap or be spaced apart. Even if they overlap, there will be gaps. By providing the second water-blocking membrane area 202, the water-blocking effect of the edge areas of the first water-blocking membrane areas 201 can be improved. When the second water-blocking membrane area 202 and the first water-blocking membrane area 201 are disposed on the same side, the first water-blocking membrane areas 201 are spaced apart, and the second water-blocking membrane area 202 is disposed in the gaps between adjacent first water-blocking membrane areas 201 to improve the water-blocking effect of the edge areas of the first water-blocking membrane areas 201.

[0039] In one embodiment, in the thickness direction of the water-blocking backsheet, the edges of the second water-blocking film region 202 and the first water-blocking film region 201 overlap each other, or the edges of the second water-blocking film region 202 and the first water-blocking film region 201 are spaced apart from each other by at least a predetermined distance. As an example, the predetermined distance is 0.8-1.1 mm. Figure 3 The diagram shows two adjacent first water-blocking membrane areas 201 spaced apart from each other. A second water-blocking membrane area 202 is provided at the interval between each first water-blocking membrane area 201. The width of the second water-blocking membrane area 202 can be less than the width of the interval area, so that the edge of the second water-blocking membrane area 202 is spaced apart from the edge of the first water-blocking membrane area 201. Alternatively, to further ensure the water-blocking effect, the width of the second water-blocking membrane area 202 can be greater than or equal to the width of the interval area, so that the edge of the second water-blocking membrane area 202 overlaps with the edge of the first water-blocking membrane area 201. The overlap width of the edges of the first water-blocking membrane area 201 and the second water-blocking membrane area 202 can be in the range of 1-2 mm.

[0040] In one embodiment, the second water-blocking membrane region 202 can also be divided into multiple sub-regions according to a certain length, with each sub-region being independent of the others, so that stress relief zones are formed between each sub-region, thereby further increasing the stress of the water-blocking membrane layer.

[0041] According to the water-blocking backplate provided by this utility model, the water-blocking effect of the water-blocking membrane layer 20 can be further guaranteed by setting the second water-blocking membrane area 202, and the water vapor intrusion generated at the edge of the first water-blocking membrane area 201 can be reduced.

[0042] Furthermore, if the number of first water-blocking film areas 201 included in the water-blocking film layer 20 is one in the width direction of the back panel substrate 10, then the number of first water-blocking film areas 201 included in the water-blocking film layer 20 in the length direction of the back panel substrate 10 is multiple, and the multiple first water-blocking film areas 201 in the length direction respectively contact and overlap with the edges of two adjacent first water-blocking film areas 201 through their two opposite edges; or, if the number of first water-blocking film areas 201 included in the water-blocking film layer 20 in the length direction of the back panel substrate 10 is one, then the number of first water-blocking film areas 201 in the width direction of the back panel substrate 10 is multiple, and the multiple first water-blocking film areas 201 in the width direction respectively contact and overlap with the edges of two adjacent first water-blocking film areas 201 through their two opposite edges.

[0043] According to the water-blocking backplate provided by this utility model, the water-blocking membrane layer 20 can be prepared by sequentially preparing each water-blocking membrane area. The multiple water-blocking membrane areas formed can improve the stress of the water-blocking membrane layer 20 while ensuring the waterproof effect of the water-blocking membrane layer 20 and the service life of the water-blocking backplate.

[0044] In one embodiment, the material of the water-blocking membrane layer 20 can be silicon oxide, aluminum oxide, or zinc oxide.

[0045] The following detailed description, using several embodiments and comparative examples, illustrates the preparation process and waterproof performance of the water-blocking backsheets with different structures provided by the embodiments of this utility model. Regardless of whether it's an embodiment or a comparative example, in the process of preparing the water-blocking backsheet, the backsheet substrate 10 first needs to be pretreated, including degreasing and corona treatment, to increase the adhesion of the water-blocking film layer 20. Then, the water-blocking backsheet is prepared using the treated backsheet substrate 10. The material of the first water-blocking film region 201 can be silicon dioxide, aluminum oxide, or zinc oxide. The following comparative examples and embodiments all use silicon dioxide to prepare the water-blocking film layer 20 as an example.

[0046] Example 1:

[0047] The preparation process of the water-blocking backplate includes steps P11 to P13:

[0048] Step P11: For the pretreated backplate substrate 10, in an atmosphere of mixed argon and oxygen, silicon dioxide is deposited on the backplate substrate 10 by vapor deposition to form a complete water-blocking film layer with a thickness of 15μm covering one main surface of the backplate substrate 10.

[0049] Step P12: Using a 50W laser, the complete water-blocking film layer is cut to form multiple independent first water-blocking film regions 201. Each first water-blocking film region 201 corresponds to one solar cell. Stress relief regions are formed at the intervals between the first water-blocking film regions 201. The spacing between the stress relief regions is 1mm, and the spacing between the cells is 0.4mm.

[0050] Step P13: A first weather-resistant adhesive layer 50 with a thickness of 10 μm is coated on the side of the water-resistant film layer 20 away from the backing substrate 10, and a first weather-resistant layer 30 with a thickness of 50 μm is adhered on the side of the first weather-resistant adhesive layer 50 away from the backing substrate 10. The first weather-resistant layer 30 is made of polyester film (PET). A second weather-resistant layer 40 with a thickness of 50 μm is coated on the other main surface of the backing substrate 10 away from the water-resistant film layer 20 using a lamination technique. The second weather-resistant layer 40 is also made of PET, resulting in the following... Figure 1 The water-blocking backplate shown.

[0051] like Figure 1 As shown, the water-blocking backplate formed in this embodiment includes the following layers stacked from bottom to top: a second weather-resistant layer 40, a backplate substrate 10, a first water-blocking film area 201, a first weather-resistant adhesive layer 50, and a first weather-resistant layer 30.

[0052] Comparative example (conventional water-blocking backplate):

[0053] The water-blocking backsheet includes a complete structure of a water-blocking film layer, a weather-resistant adhesive layer, and a weather-resistant layer stacked from the inside to the outside on one side of the backsheet substrate, and a weather-resistant layer on the other side of the backsheet substrate. The preparation of the complete structure of the water-blocking film layer is the same as step P11 in Example 1 above. The preparation of the weather-resistant adhesive layer and weather-resistant layer stacked on the outside of the complete structure of the water-blocking film layer, and the weather-resistant layer on the other side of the backsheet substrate, is the same as step P13 in Example 1 above. That is, the preparation process of this comparative example's water-blocking backsheet omits step P12 compared to Example 1.

[0054] The performance of the water-blocking backsheet prepared in Example 1 and the water-blocking backsheet prepared in the comparative example were tested under different test environments. These different test environments included:

[0055] 1. DH1000h+Static load 5400Pa: The water-blocking backplate of Example 1 and the conventional water-blocking backplate of the comparative example were placed in a humid and hot environment (humidity 85%, temperature 85℃) for 1000 hours, and then the water-blocking backplate was subjected to a static load of 5400Pa.

[0056] 2. Static load 5400Pa+DH1000h: First, the water-blocking backplate of Example 1 and the conventional water-blocking backplate of the comparative example are subjected to a static load of 5400Pa. Then, the water-blocking backplate is placed in a humid and hot environment (humidity 85%, temperature 85℃) for 1000 hours.

[0057] The test results are compared in Table 1 below:

[0058]

[0059] As can be seen from the test results in Table 1 above, under the test conditions of DH1000h + static load 5400Pa, the component power loss of the water-blocking backsheet of Example 1 and the water-blocking backsheet of the comparative example is the same. However, under the test conditions of static load 5400Pa + DH1000h, the component power loss of the water-blocking backsheet of Example 1 is lower than that of the conventional water-blocking backsheet of the comparative example. Therefore, it can be concluded that the water-blocking backsheet of Example 1 has superior performance compared to the conventional water-blocking backsheet of the comparative example, providing better waterproofing and extending the service life of the water-blocking backsheet.

[0060] Example 2:

[0061] The preparation process of the water-blocking backplate includes steps P21 to P23:

[0062] Step P21: For the pre-treated backplate substrate 10, cover one side of the backplate substrate 10 by means of a mask according to the pre-designed pattern, and deposit silicon dioxide on the uncovered area of ​​the backplate substrate 10 by means of vapor deposition to form a plurality of first water-blocking film regions 201 with a thickness of 20μm and spaced apart.

[0063] Step P22: Cover each of the first water-blocking film areas 201 with a mask, exposing the edges of each of the first water-blocking film areas 201. In an atmosphere of mixed argon and oxygen, deposit silicon dioxide in the unmasked area of ​​the backplate substrate 10 by vapor deposition to form multiple first water-blocking film areas 201 with a thickness of 20 μm. The first water-blocking film areas 201 formed in step P22 are arranged alternately with the first water-blocking film areas 201 formed in step P11. The first water-blocking film areas 201 formed in step P22 overlap with the upper side of the edge of the first water-blocking film areas 201 formed in step P11 on the side away from the backplate substrate 10. In the length direction of the backplate substrate 10, the overlap width between the edges of the first water-blocking film areas 201 formed in step P22 and the first water-blocking film areas 201 formed in step P11 is 2 mm. In the width direction of the backplate substrate 10, the overlap width between the edges of the first water-blocking film areas 201 formed in step P22 and the first water-blocking film areas 201 formed in step P11 is 1 mm.

[0064] Step P23 is the same as step P13 above, and will not be repeated here.

[0065] Example 2 yielded the following result: Figure 4 The structures shown were used to perform performance tests on the water-blocking backsheet prepared in Example 2 and the conventional water-blocking backsheet prepared in the comparative example under different test environments. The different test environments included:

[0066] 1. DH1000h+static load 5400Pa: The water-blocking backplate of Example 2 and the conventional water-blocking backplate of the comparative example were placed in a humid and hot environment (humidity 85%, temperature 85℃) for 1000 hours, and then the water-blocking backplate was subjected to a static load of 5400Pa.

[0067] 2. Static load 5400Pa+DH1000h: First, the water-blocking backplate of Example 2 and the conventional water-blocking backplate of the comparative example are subjected to a static load of 5400Pa. Then, the water-blocking backplate is placed in a humid and hot environment (humidity 85%, temperature 85℃) for 1000 hours.

[0068] The test results of Example 2 and the comparative example are compared in Table 2:

[0069]

[0070] As can be seen from the test results in Table 2 above, under the test conditions of DH1000h + static load 5400Pa, the component power loss of the water-blocking backsheet of Example 2 is the same as that of the water-blocking backsheet of the comparative example. However, under the test conditions of static load 5400Pa + DH1000h, the component power loss of the water-blocking backsheet of Example 2 is lower than that of the conventional water-blocking backsheet of the comparative example. Therefore, it can be concluded that the water-blocking backsheet of Example 2 has superior performance compared to the conventional water-blocking backsheet of the comparative example, providing better waterproofing and extending the service life of the water-blocking backsheet.

[0071] Example 3:

[0072] The preparation process of the water-blocking backplate includes steps P31 to P33:

[0073] Step P31: For the pre-treated backplate substrate 10, cover one side of the backplate substrate 10 by means of a mask according to the pre-designed pattern. In the atmosphere of a mixed gas of argon and oxygen, deposit silicon dioxide on the uncovered area of ​​the backplate substrate 10 by vapor deposition to form each first water-blocking film region 201 with a thickness of 20μm.

[0074] Step P32: Cover the other side of the backplate substrate 10 with a mask according to the pre-designed layout, and deposit silicon dioxide in the part not covered by the mask to obtain a second water-blocking film region 202 with a thickness of 20μm. The projection overlap width between the second water-blocking film region 202 and the first water-blocking film region 201 is 2mm.

[0075] Step P33 is the same as step P13 above, and will not be repeated here. The result is as follows: Figure 3 The structure of the water-blocking backplate is shown.

[0076] Furthermore, the performance of the water-blocking backsheet prepared in Example 3 and the conventional water-blocking backsheet prepared in the comparative example were tested under different test environments. These different test environments included:

[0077] 1. DH1000h+static load 5400Pa: The water-blocking backplate of Example 3 and the conventional water-blocking backplate of the comparative example were placed in a humid and hot environment (humidity 85%, temperature 85℃) for 1000 hours, and then the water-blocking backplate was subjected to a static load of 5400Pa.

[0078] 2. Static load 5400Pa+DH1000h: First, the water-blocking backplate of Example 3 and the conventional water-blocking backplate of the comparative example are subjected to a static load of 5400Pa. Then, the water-blocking backplate is placed in a humid and hot environment (humidity 85%, temperature 85℃) for 1000 hours.

[0079] The test results of Example 3 and the comparative example are compared in Table 3:

[0080]

[0081] As can be seen from the test results in Table 3 above, under the test conditions of DH1000h + static load 5400Pa, the component power loss of the water-blocking backsheet of Example 3 is the same as that of the water-blocking backsheet of the comparative example. However, under the test conditions of static load 5400Pa + DH1000h, the component power loss of the water-blocking backsheet of Example 3 is lower than that of the conventional water-blocking backsheet of the comparative example. Therefore, it can be concluded that the water-blocking backsheet of Example 3 has superior performance compared to the conventional water-blocking backsheet of the comparative example, providing better waterproofing and extending the service life of the water-blocking backsheet.

[0082] A comparison of the water-blocking backsheets of the above embodiments with those of the comparative example shows that, under the test conditions of DH1000h + static load 5400Pa and static load 5400Pa + DH1000h, the embodiments of this application exhibit better water-blocking performance, while the comparative example shows poor water-blocking performance under the test condition of static load 5400Pa + DH1000h. This indicates that the conventional water-blocking backsheet of the comparative example has good water-blocking performance when not subjected to static load, but after being subjected to static load, the water-blocking performance decreases due to stress-induced cracks in the entire water-blocking membrane layer. In contrast, the embodiments of this application, by using multiple independent water-blocking membrane areas to form the water-blocking membrane layer 20, exhibit better water-blocking performance when not subjected to static load. Because the water-blocking membrane areas have stress-relieving zones due to mutual resistance, the stress of the entire water-blocking membrane layer 20 is greatly increased, improving the strain resistance of the water-blocking membrane layer 20 and reducing the risk of cracking. Even after being subjected to static load, it can still ensure good water-blocking performance.

[0083] Furthermore, this utility model also provides a photovoltaic module. Figure 6 This is a schematic diagram of the structure of a photovoltaic module provided in an embodiment of the present invention. Figure 6 As shown, the photovoltaic module may include:

[0084] The front panel, front adhesive film, battery array, rear adhesive film, and the aforementioned water-blocking backplate are stacked in sequence.

[0085] A photovoltaic module's cell array comprises multiple uniformly arranged cells. To ensure water-blocking performance, each first water-blocking film area 201 on the water-blocking backsheet corresponds to the position of a cell. Specifically, each first water-blocking film area 201 covers at least one cell's area, and the first water-blocking film area 201 should at least cover the edge of the cell. If the sizes of the first water-blocking film areas 201 are not identical, the number of cells corresponding to each first water-blocking film area 201 can also be different. In addition to the first water-blocking film areas 201, a second water-blocking film area 202 can also be provided. The first water-blocking film areas 201 and the second water-blocking film areas 202 are located on the same side or both sides of the backsheet substrate. Through their cooperation, the waterproofing effect of the water-blocking backsheet is improved.

[0086] In one embodiment, two adjacent first water-blocking film regions 201 of the water-blocking backsheet are spaced apart, and the distance between two adjacent first water-blocking film regions 201 is smaller than the distance between adjacent battery cells.

[0087] In the water-blocking backsheet, there is a spaced-apart structure between two adjacent first water-blocking film areas 201. The spacing between them should be at least less than the distance between two adjacent battery cells to ensure the water-blocking effect of the backsheet. For example, if the distance between the battery cells is 1 mm, then the spacing between each spaced-apart first water-blocking film area 201 should be less than or equal to 1 mm.

[0088] According to the embodiments of this utility model, the photovoltaic module can achieve waterproofing through a water-blocking backsheet with multiple independent water-blocking film areas. Simultaneously, the increased stress and strain resistance of the water-blocking backsheet reduce the risk of cracking and significantly improve its waterproofing performance, thereby enhancing the overall waterproofing performance of the photovoltaic module. Specifically, the first water-blocking film area 201 corresponding to the solar cell prevents moisture intrusion into the cell area, protecting critical components and thus extending the lifespan of the photovoltaic module.

[0089] The specific embodiments described above do not constitute a limitation on the scope of protection of this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can occur depending on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A water-blocking backsheet for photovoltaic modules, characterized in that, include: The back plate substrate (10) and the water-blocking membrane layer (20) disposed on at least one side of the back plate substrate (10). The water-blocking membrane layer (20) includes at least two independent first water-blocking membrane regions (201), wherein each first water-blocking membrane region (201) corresponds to at least one or more cells of the photovoltaic module.

2. The water-blocking backplate according to claim 1, characterized in that, The water-blocking film layer (20) is disposed on one side of the back panel substrate (10), and the water-blocking back panel further includes a first weather-resistant layer (30), a second weather-resistant layer (40), and a first weather-resistant adhesive layer (50). The first weather-resistant adhesive layer (50) and the first weather-resistant layer (30) are stacked from the inside to the outside on the side of the water-blocking film layer (20) away from the back plate substrate (10); The second weather-resistant layer (40) is disposed on the other side of the back plate substrate (10) away from the water-blocking film layer (20).

3. The water-blocking backplate according to claim 1, characterized in that, The water-blocking film layer is provided on both sides of the back panel substrate (10). The water-blocking back panel also includes a first weather-resistant layer (30), a second weather-resistant layer (40), a first weather-resistant adhesive layer (50), and a second weather-resistant adhesive layer (60). The first weather-resistant adhesive layer (50) and the first weather-resistant layer (30) are stacked from the inside to the outside on the side of the water-blocking film layer (20) of one of the back plate substrates (10) away from the back plate substrate (10); The second weather-resistant adhesive layer (60) and the second weather-resistant layer (40) are stacked from the inside to the outside on the side of the other water-blocking film layer (20) of the back plate substrate (10) away from the back plate substrate (10).

4. The water-blocking backplate according to claim 1, characterized in that, The water-blocking film layer (20) further includes a second water-blocking film region (202), which corresponds to the gap between adjacent cells of the photovoltaic module.

5. The water-blocking backplate according to claim 4, characterized in that, The second water-blocking membrane area (202) and the first water-blocking membrane area (201) are located on different sides or the same side of the back plate substrate (10).

6. The water-blocking backplate according to claim 5, characterized in that, In the thickness direction of the water-blocking backplate, the edges of the second water-blocking film area (202) and the first water-blocking film area (201) overlap each other, or the edges of the second water-blocking film area (202) and the first water-blocking film area (201) are spaced apart from each other by at least a predetermined distance.

7. The water-blocking backplate according to claim 1, characterized in that, The edges of two adjacent first water-blocking membrane regions (201) overlap each other. A portion of the edge of one of the first water-blocking membrane regions (201) overlaps the upper side of the edge of its adjacent portion of the first water-blocking membrane region (201), and another portion of the edge overlaps the lower side of the edge of its adjacent other portion of the first water-blocking membrane region (201); or, all the edges of one of the first water-blocking membrane regions (201) overlap the upper or lower side of the edges of all the adjacent first water-blocking membrane regions (201).

8. The water-blocking backplate according to claim 1, characterized in that, The edges of two adjacent first water-blocking membrane regions (201) are spaced apart by at least a predetermined distance, the predetermined distance being 0.8-1.1 mm.

9. A photovoltaic module, characterized in that, include: The front plate, front adhesive film, battery array, rear adhesive film, and water-blocking backplate according to any one of claims 1 to 8 are stacked in sequence.

10. The photovoltaic module according to claim 9, characterized in that, The two adjacent first water-blocking film areas (201) of the water-blocking backplate are spaced apart, and the distance between the two adjacent first water-blocking film areas (201) is smaller than the distance between the adjacent battery cells.

Images