Photovoltaic cell string and photovoltaic module
By spraying a barrier coating on key areas of the photovoltaic cell string, the problem of water vapor and oxygen corrosion of the photovoltaic module was solved, improving the module's protective performance and economy.
Patent Information
- Application Number
- CN202520294318.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-21
- Publication Date
- 2026-01-09
- Estimated Expiration
- 2035-02-21
AI Technical Summary
The water-blocking performance requirements of existing photovoltaic modules vary in different regions, resulting in high cost or low efficiency of encapsulation solutions, and traditional encapsulation materials cannot effectively prevent water vapor and oxygen corrosion.
Protective coatings are sprayed onto key areas of the photovoltaic cell string, including covering edges and easily corroded areas. EVOH, PVDC, PIB, PE, POE, PP or silicon-based coatings are used to block oxygen and water vapor and meet specific transmittance requirements.
It achieves a high-performance corrosion protection effect at a cost-effective price, improves the stability and lifespan of photovoltaic modules, and reduces the overall cost.
Smart Images
Figure CN223786428U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of photovoltaic technology, and in particular to a photovoltaic cell string and a photovoltaic module. Background Technology
[0002] With the booming development of the photovoltaic industry, new types of photovoltaic cells are constantly emerging, such as perovskite, heterojunction, and TOPCon crystalline silicon cells. They all have a common characteristic: they are sensitive to water and oxygen in the environment, and are easily corroded, which can cause a decrease in power generation.
[0003] In related technologies, the mainstream approach to improve cell corrosion is to enhance the water vapor transmission rate of the encapsulation film. This includes: adding an additional inorganic water-blocking layer (this method is costly and unsuitable for improving the water-blocking performance of the front encapsulation film); adding water-blocking fillers (which can indeed improve the overall water-blocking effect, but excessive fillers can reduce the light transmittance of the encapsulation film and result in insufficient adhesion between the film and the cell and glass, leading to a long-term decrease in the power generation efficiency of the photovoltaic module); or using a main resin material with higher water-blocking properties (this approach often has higher raw material costs and lacks competitive advantage).
[0004] From the perspective of module structure, the backsheet of a single-glass module is made of polymer material. Whether it is a regular white backsheet or a transparent backsheet, its water resistance is not high. Double-glass modules use glass with excellent water resistance on both the upper and lower layers, so there is basically no problem of water vapor passing through the front and back of the photovoltaic module. However, there is still a risk of water vapor passing through places such as the wiring ports and the edges around the module.
[0005] It is evident that the water-blocking performance requirements for photovoltaic modules vary in different regions, thus necessitating the search for encapsulation solutions that balance economic efficiency and barrier performance. Utility Model Content
[0006] To address the aforementioned issues, this application employs a photovoltaic cell string with a protective coating applied to key areas, which can cost-effectively solve the problem of damp heat corrosion in photovoltaic modules.
[0007] To achieve the above objectives, the technical solution adopted in this application is as follows:
[0008] One aspect of this application discloses a photovoltaic cell string, which includes cells connected in series and / or in parallel. At least one side of the photovoltaic cell string has a sprayed area with a sprayed coating layer. The sprayed area includes a first sprayed area covering at least a portion of the edge of the photovoltaic cell string, and the first sprayed area is strip-shaped. The sprayed coating layer satisfies an oxygen permeability of less than or equal to 100 cm⁻¹. 3 / (m 2 •24h•0.1MPa) and / or water vapor transmission rate less than or equal to 10g / (m2 ·day).
[0009] Furthermore, the width of the first spraying area is 3mm to 150mm.
[0010] Furthermore, the coating area also includes a second coating area covering at least part of the adjacent apex corners of the adjacent solar cells.
[0011] Furthermore, the area of the second spraying zone is 50 mm. 2 ~50000mm 2 .
[0012] Furthermore, the shape of the second spraying area is a closed figure composed of at least one of curves or straight lines.
[0013] Furthermore, the sprayed coating is one of EVOH coating, PVDC coating, PIB coating, PE coating, POE coating, PP coating or silicone-based coating.
[0014] Furthermore, the spray coating can be configured as a single layer or multiple layers.
[0015] Furthermore, the thickness of the sprayed coating ranges from 5 μm to 200 μm.
[0016] This application also provides a photovoltaic module, which includes a front panel, an encapsulating film, a photovoltaic cell string, an encapsulating film and a back panel, wherein the photovoltaic cell string is the aforementioned photovoltaic cell string and the cell is an N-type cell.
[0017] Furthermore, the solar cells are TOPCon solar cells, HJT solar cells, or BC solar cells.
[0018] Furthermore, when the front and back panels are made of glass, a spray coating is provided on the spraying area of at least one side of the photovoltaic cell string; when the front and / or back panels are not made of glass, a spray coating is provided on the entire surface of the cells on at least one side of the photovoltaic cell string or on the periphery of each cell in the photovoltaic cell string.
[0019] Therefore, this application has at least the following technical effects:
[0020] 1. In this application, a protective coating is applied to key locations in the photovoltaic cell string to achieve corrosion protection for the photovoltaic cells and grid lines;
[0021] 2. In this application, by applying a protective coating only to key locations in the photovoltaic cell string that are prone to corrosion, the purpose of corrosion prevention can be achieved more efficiently, avoiding material waste and improving cost-effectiveness. Attached Figure Description
[0022] Figure 1This is a schematic diagram of the structure of a photovoltaic cell string provided in an embodiment of this application;
[0023] Figure 2 A schematic diagram of the structure of a photovoltaic cell string with a first type of spray coating area provided in an embodiment of this application;
[0024] Figure 3 This is a schematic diagram of the structure of a photovoltaic cell string with a second type of spraying area provided in an embodiment of this application;
[0025] Figure 4 This is a schematic diagram of the structure of a photovoltaic cell string with a third type of spraying area provided in an embodiment of this application;
[0026] Figure 5 This is a schematic diagram of the structure of a photovoltaic cell string with a fourth type of spraying area provided in an embodiment of this application;
[0027] Figure 6 This is a schematic diagram of the structure of a photovoltaic cell string with a fifth type of spraying area provided in an embodiment of this application;
[0028] Figure 7 This is a schematic diagram of the structure of a photovoltaic cell string with a sixth type of spraying area provided in an embodiment of this application;
[0029] Figure 8 A schematic diagram of the structure of a photovoltaic cell string with a seventh coating area provided in an embodiment of this application;
[0030] In the diagram: photovoltaic cell string 100, cell 11, spraying area 12, first spraying area 121, second spraying area 122. Detailed Implementation
[0031] To enable those skilled in the art to better understand the present application, the technical solutions in specific embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings.
[0032] This application provides an embodiment of, as follows: Figure 1 The photovoltaic cell string 100 shown is a component of a photovoltaic module and can be used to assemble a photovoltaic module. The photovoltaic cell string 100 consists of solar cells 11 connected in series and / or in parallel. Figure 2As shown, at least one side of the photovoltaic cell string 100 is provided with a sprayed area 12, on which a sprayed coating is applied. The sprayed coating provides protection to the sprayed area 12 of the photovoltaic cell string 100, preventing corrosion of certain components and increasing the lifespan and stability of the photovoltaic module. Specifically, the sprayed coating acts as a barrier against moisture and oxygen, preventing them from seeping into the photovoltaic module through the substrate or from the edges and terminals, thus preventing corrosion of relevant areas of the photovoltaic cell string 100. The sprayed area 12 on the photovoltaic cell string 100 includes a first sprayed area 121, which covers at least a portion of the edge area of the photovoltaic cell. The edge area of the photovoltaic cell string 100 is located where the photovoltaic substrate and the photovoltaic module frame meet. Moisture and oxygen can easily seep into the photovoltaic module through the gaps at the joint, making the edge area of the photovoltaic cell string 100 more susceptible to corrosion. Applying a spray coating to the edge region of the photovoltaic cell string 100 prevents moisture and oxygen from seeping into the gaps at the junction of the photovoltaic substrate and the photovoltaic module frame, thus preventing corrosion of the photovoltaic cell string 100. The edge of the photovoltaic cell string 100 is essentially strip-shaped, and the first spray coating area 121 covering at least part of the edge of the photovoltaic cell string 100 is also essentially strip-shaped. Furthermore, applying the aforementioned spray coating to the surface of the photovoltaic cell string 100 allows the use of EVA encapsulant, which has relatively poor oxygen and moisture barrier properties but is less expensive, in the photovoltaic module. This can reduce the overall cost of the photovoltaic module to some extent, while also providing better weather resistance and reliability.
[0033] As an optional implementation, the sprayed coating satisfies an oxygen permeability of less than or equal to 100 cm⁻¹. 3 / (m 2 The sprayed coating (24h, 0.1MPa) prevents gases such as oxygen that have penetrated into the photovoltaic module from passing through the coating and contacting the surface of the photovoltaic cell string 100, thus avoiding corrosion of the photovoltaic cell string 100 by oxidizing gases such as oxygen or other corrosive gases. The water vapor transmission rate is less than or equal to 10 g / (m²). 2 The spray coating prevents moisture that has penetrated the photovoltaic module from passing through it and contacting the surface of the photovoltaic cell string 100, thus avoiding corrosion of the photovoltaic cell string 100 by moisture. Depending on the application scenario of the photovoltaic module, the spray coating may only meet the above-mentioned requirements for oxygen permeability, or only meet the above-mentioned requirements for water vapor permeability, or it may meet both the above-mentioned requirements for oxygen permeability and water vapor permeability simultaneously, enabling the photovoltaic module to have a wider range of applications.
[0034] As an optional implementation method, such as Figure 2As shown, the width W of the first coating area 121 ranges from 3mm to 150mm. The width of the first coating area 121 is selected comprehensively based on the type of solar cell 11, the material and shape of the photovoltaic module frame, and the application scenario of the photovoltaic module. When the type of solar cell 11 is more susceptible to corrosion, the width of the first coating area 121 can be appropriately increased. When the material and shape of the photovoltaic module frame have a higher water vapor barrier effect, the width of the first coating area 121 can be appropriately decreased. When the photovoltaic module is applied in a high humidity environment, the width of the first coating area 121 can be increased, and when the photovoltaic module is applied in a dry environment, the width of the first coating area 121 can be decreased. Setting the width W of the first coating area 121 in the range of 3mm to 150mm can satisfy the oxygen and water vapor barrier effect, preventing the photovoltaic cell string 100 from being corroded, while also reducing the overall cost of the photovoltaic module.
[0035] As an optional implementation, the first spraying area 121 can be as follows: Figure 2 The border-shaped area shown is composed of several rectangles. The first spraying area 121 can also be as follows: Figure 3 The area shown is a border-shaped region composed of straight lines and / or curves. The shape of the first spraying area 121 needs to be set by considering the material and shape of the photovoltaic module frame and the material of the solar cells 11. If the probability or degree of water vapor or oxygen penetration is basically equal at all points on the photovoltaic module frame, the first spraying area 121 can be set as a rectangular border with a uniform width. If the probability or degree of water vapor or oxygen penetration varies at different points on the photovoltaic module frame due to the shape of the photovoltaic module frame, the width of the first spraying area 121 can be increased accordingly for areas with higher penetration probability or degree, ultimately forming a first spraying area 121 with varying width and a more irregular shape.
[0036] As an optional implementation method, such as Figure 2As shown, the spraying area 12 also includes a second spraying area 122 covering at least a portion of the adjacent apex corners of adjacent solar cells 11. Due to specific circuit designs, some double-glass modules require through-holes in the photovoltaic module substrate for wire routing; these through-holes are commonly referred to as center holes. Center holes are typically located in the area where the apex corners of adjacent solar cells 11 are located. Specifically, for photovoltaic modules composed of rectangular solar cell arrays 11, the center holes are located in the area where the four apex corners of four adjacent solar cells 11 are located, and the center holes are essentially located at the center of this area. Similar to the edges of the photovoltaic module, the portion of the photovoltaic cell string 100 corresponding to the center hole location is also highly susceptible to corrosion. Oxygen and moisture can easily enter the interior of the photovoltaic module through the center holes on the photovoltaic substrate, thereby corroding the photovoltaic cell string 100. To address the corrosion of the photovoltaic cell string 100 caused by the central hole in the photovoltaic substrate, a second spraying area 122 is provided on the photovoltaic cell string 100 in the region corresponding to the central hole in the photovoltaic substrate. A spray coating is applied to the second spraying area 122 to enhance the oxygen and moisture barrier properties of the corresponding region, thereby improving its corrosion resistance. Preferably, the second spraying area 122 at least covers the apex region of the adjacent cell 11 or the edge region of the cell 11, to protect areas more susceptible to moisture and oxygen erosion, such as the apex and edges of the cell 11.
[0037] As an optional implementation, the area of the second spraying zone 122 is 50 mm². 2 ~50000mm 2 The width of the second coating area 122 is selected comprehensively based on the type of solar cell 11, the size and shape of the central hole, and the application scenario of the photovoltaic module. When the type of solar cell 11 is more susceptible to corrosion, the width of the second coating area 122 can be appropriately increased. When the size of the central hole on the photovoltaic substrate is small, the range and area of the second coating area 122 can be appropriately reduced; when the size of the central hole on the photovoltaic substrate is large, the range and area of the second coating area 122 can be appropriately increased. When the photovoltaic module is applied in a high-humidity environment, the width of the second coating area 122 can be increased; when the photovoltaic module is applied in a dry environment, the width of the second coating area 122 can be decreased. The area of the second coating area 122 is set to 50 mm². 2 Up to 50000mm 2 Within this range, it can satisfy the oxygen and water vapor barrier effect, preventing the photovoltaic cell string from being corroded, and at the same time reduce the overall cost of photovoltaic modules.
[0038] As an optional implementation, the second coating area 122 is a closed shape composed of at least one of curves or straight lines. The shape of the second coating area 122 is mainly determined by the shape of the central hole, the distance between the central hole and the adjacent solar cell 11, and the shape of the solar cell 11. For example, when the size of the central hole is large, the size of the second coating area 122 should also be relatively large; when the distance between the central hole and the adjacent solar cell 11 is large, the size of the second coating area 122 can be set to be relatively small. Figure 4 As shown, the second spraying area 122 can be a circular area centered on the center point of the central hole. For example... Figure 5 As shown, the second spraying area 122 can be a rectangular area centered on the central hole. For example... Figure 6 As shown, the shape of the second spraying area 122 can also be a derivative of the circular shape. For example, areas in the circular area that have little impact on the corrosion problem of the battery cell 11 can be removed to reduce production costs.
[0039] Furthermore, for the photovoltaic cell string 100 used in double-glass modules, since both sides of the module's substrate are made of glass, it has better inherent protective performance. Therefore, the spraying area 12 and spray coating can be set only around the perimeter of the photovoltaic cell string 100 and / or near the central hole. However, for the photovoltaic cell string 100 used in single-glass modules, since one side of the module's substrate is a non-glass substrate, its inherent protective performance is poor. Therefore, a spraying area and spray coating can be set around the perimeter of each cell in the photovoltaic cell string 100, at least on the side closest to the non-glass substrate (e.g., ...). Figure 7 (as shown), or spraying a coating layer (such as) onto the entire surface of each cell in the photovoltaic cell string 100, at least on the side closest to the non-glass substrate. Figure 7 (As shown).
[0040] As an optional implementation, the sprayed coating is one of the following: EVOH coating, PVDC coating, PIB coating, PE coating, POE coating, PP coating, or silicon-based coating. EVOH (ethylene-vinyl alcohol copolymer) coating has high oxygen barrier capability, preventing oxygen from contacting the surface of the photovoltaic cell string 100 and protecting it from oxygen oxidation and corrosion. PVDC (polyvinylidene chloride) coating has high gas barrier capability, providing good oxygen barrier effect. PE (polyethylene) coating has excellent water vapor barrier capability, preventing water vapor penetrating into the photovoltaic module from contacting the surface of the photovoltaic cell string 100 and protecting it from water vapor corrosion. POE (polyolefin elastomer) coating has better water vapor barrier effect than EVA resin and, when applied to photovoltaic modules using EVA encapsulation films, can also improve the overall water-blocking performance of the photovoltaic module. PIB (polyisobutylene) coating and PP (polypropylene) coating have excellent water vapor barrier capability. Silicon-based coatings are mainly composed of silicon oxides and other materials, and can effectively block oxygen and water vapor. It is understood that any suitable method can be used to create the aforementioned spray coating in the spraying area 12 of the photovoltaic cell string 100. Specifically, the following methods can be used to prepare the spray coating on the surface of the photovoltaic cell string 100: raw materials capable of forming the aforementioned spray coating (mainly for resin coatings) are melted or prepared into a dispersion and then uniformly sprayed onto the corresponding spraying area in the photovoltaic cell string; or raw materials (mainly for inorganic coatings) are deposited onto the corresponding spraying area 12 in the photovoltaic cell string 100 using vacuum deposition (including vacuum evaporation, magnetron sputtering, and ion sputtering, etc.). Then, a photovoltaic module is manufactured through conventional photovoltaic module encapsulation processes. The raw material powder can uniformly form a film layer with water vapor and / or oxygen barrier functions on the surface of the photovoltaic cell string 100.
[0041] As an optional implementation, the sprayed coating can be single-layered or multi-layered. Depending on the actual oxygen and moisture barrier requirements, one or more sprayed coatings can be applied to the spraying area 12. Furthermore, multi-layered sprayed coatings can be of the same type or different types, depending on the needs. Specifically, two sprayed coatings can be applied to the spraying area 12. Both coatings can be simultaneously a POE coating, or they can be an EVOH coating and a PE coating, respectively.
[0042] As an optional implementation, the thickness of the sprayed coating ranges from 5 μm to 200 μm. The thickness of the sprayed coating is selected comprehensively based on the application scenario, the required water vapor and oxygen barrier properties, and the coating material used. A coating thickness within the above range achieves the combined effect of water vapor and oxygen barrier properties while avoiding unnecessary cost increases due to excessive coating thickness.
[0043] This application embodiment also provides a photovoltaic module, which includes a front panel, an encapsulating film, a photovoltaic cell string, an encapsulating film and a back panel stacked in sequence. The photovoltaic cell string is the aforementioned photovoltaic cell string 100, and the cell 11 is an N-type cell.
[0044] As an alternative implementation, the solar cells are TOPCon solar cells, HJT solar cells, or BC solar cells.
[0045] As an optional implementation, when the front and rear panels are glass substrates, a coating layer (such as...) is provided on at least one side of the photovoltaic cell string 100 in the spraying area 12. Figures 2 to 6 (As shown in the diagram). When both the front and back panels are made of glass substrates, both sides of the photovoltaic module are glass substrates. Glass substrates themselves have good moisture and oxygen barrier properties. Therefore, it is only necessary to solve the problem of moisture and oxygen seeping into the photovoltaic module from the edges and central holes. This can be achieved by applying a spray coating to the corresponding positions of the edges and central holes of the photovoltaic cell string 100. This design can solve the problem of corrosion of the photovoltaic cell string 100 caused by moisture and oxygen, while also reducing the overall cost.
[0046] As an optional implementation, when the front panel and / or rear panel are non-glass substrates, a spray coating is applied to the periphery of each cell on at least one side of the photovoltaic cell string (e.g., ...). Figure 7 (as shown) or the entire surface of at least one side of the photovoltaic cell string (e.g. Figure 8 (As shown in the figure). When at least one side of the photovoltaic module uses a non-glass substrate, the barrier properties against water vapor and oxygen on that side of the photovoltaic module are relatively poor. Therefore, it is necessary to apply a spray coating to the entire surface of the photovoltaic cell string 100 or to apply a spray coating to the edges of each cell in the photovoltaic cell string 100 to better solve the problem of corrosion of the photovoltaic cell string 100 caused by water vapor and oxygen.
[0047] In this embodiment, a coating is applied to key areas of the photovoltaic module that are susceptible to corrosion by water vapor and oxygen, thus solving the corrosion problem caused by water vapor and oxygen on the photovoltaic cell string and reducing the overall cost of the photovoltaic module.
[0048] Finally, it should be noted that the above are only some preferred embodiments of this application and are not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.
Claims
1. A photovoltaic cell string for assembling photovoltaic modules, Its characteristics are: The photovoltaic cell string includes cells connected in series and / or in parallel. At least one side of the photovoltaic cell string has a sprayed area, and the sprayed area has a sprayed coating. The sprayed area includes a first sprayed area covering at least a portion of the edge of the photovoltaic cell string, and the first sprayed area is strip-shaped. The sprayed coating satisfies an oxygen permeability of less than or equal to 100 cm⁻¹. 3 / (m 2 •24h•0.1MPa) and / or water vapor transmission rate less than or equal to 10g / (m 2 ·day).
2. The photovoltaic cell string according to claim 1, characterized in that: The width of the first sprayed area is 3mm to 150mm.
3. The photovoltaic cell string according to claim 1, characterized in that: The sprayed area also includes a second sprayed area covering at least a portion of the adjacent apex corners of the adjacent solar cells.
4. The photovoltaic cell string according to claim 3, characterized in that: The area of the second sprayed zone is 50mm. 2 ~50000mm 2 .
5. The photovoltaic cell string according to claim 3, characterized in that: The shape of the second sprayed area is a closed figure composed of at least one of curves or straight lines.
6. The photovoltaic cell string according to claim 1, characterized in that: The sprayed coating is one of EVOH coating, PVDC coating, PIB coating, PE coating, POE coating, PP coating or silicon-based coating.
7. The photovoltaic cell string according to claim 1, characterized in that: The spray coating can be configured as a single layer or multiple layers.
8. The photovoltaic cell string according to claim 1, characterized in that: The thickness of the sprayed coating is 5μm to 200μm.
9. A photovoltaic module, characterized in that: It includes a front panel, an encapsulating film, a photovoltaic cell string, an encapsulating film, and a back panel, wherein the photovoltaic cell string is the photovoltaic cell string according to any one of claims 1 to 8, and the cell is an N-type cell.
10. The photovoltaic module according to claim 9, characterized in that: When the front and rear panels are made of glass, the photovoltaic cell string has the spray coating applied to the spray area on at least one side of the photovoltaic cell string. When the front panel and / or rear panel are not glass, the spray coating is applied to the entire surface of the cells on at least one side of the photovoltaic cell string or to the periphery of each cell in the photovoltaic cell string.