A photovoltaic module

Abstract

This application relates to a photovoltaic module, which includes two cover plates, two layers of encapsulant film, solar cells, and solder ribbons. The two cover plates are distributed along the thickness direction of the photovoltaic module and are located on the outer side of the photovoltaic module along the thickness direction. The two layers of encapsulant film, the solar cells, and the solder ribbons are all located between the two cover plates, and the solder ribbons connect adjacent solar cells. The basis weight y of a single layer of encapsulant film and the diameter X of the solder ribbon satisfy the following relationship: When the basis weight y of a single layer of encapsulant film and the diameter X of the solder ribbon satisfy the above relationship, they achieve a suitable fit. At this time, during the lamination process, the encapsulant film can protect the solar cells, reduce the risk of damaging the solar cells during lamination, and improve the reliability and service life of the solar cells; at the same time, it improves the light absorption of the solar cells and increases the power of the photovoltaic module.

Description

Technical Field

[0001] This application relates to the field of photovoltaic technology, and more particularly to a photovoltaic module. Background Technology

[0002] Photovoltaic modules are commonly used for generating solar power. A photovoltaic module consists of solar cells, solder ribbons, encapsulating film, and a cover plate. The encapsulating film encapsulates the module and protects the solar cells, while the solder ribbons connect the cells and transmit the electrons generated by them. The cover plate protects the photovoltaic module. A persistent problem in the photovoltaic module industry is its low photoelectric conversion efficiency. Summary of the Invention

[0003] This application provides a photovoltaic module, which includes two cover plates, two layers of encapsulant film, solar cells, and solder ribbons. The two cover plates are distributed along the thickness direction of the photovoltaic module and are located on the outer side of the photovoltaic module along the thickness direction. The two layers of encapsulant film, the solar cells, and the solder ribbons are all located between the two cover plates, and the solder ribbons connect two adjacent solar cells. The basis weight y of a single layer of encapsulant film and the diameter X of the solder ribbon satisfy the following relationship:

[0004]

[0005] Where V is the volume of the space between the cover plate and the solar cell, a is the length of the adhesive film, b is the width of the adhesive film, n is the number of main busbars of the photovoltaic module; ρ is the density of the adhesive film, and ρ satisfies 0.87 g / cm³. 3 ≤ρ≤0.96g / cm 3 .

[0006] When the basis weight y of the single-layer encapsulant film and the diameter X of the solder ribbon satisfy the above formula, a suitable matching relationship is achieved between them. This reduces the risk of the encapsulant film having too small a basis weight (too thin an encapsulant film) and the solder ribbon having too large a diameter, thus enabling the encapsulant film to protect the solar cells during lamination, reducing the risk of damaging the solar cells during lamination, and improving the reliability and lifespan of the solar cells. At the same time, it also reduces the risk of the encapsulant film having too large a basis weight (too thick an encapsulant film) and the solder ribbon having too small a diameter, thus reducing the impact of an excessively thick encapsulant film on the solar cells' light absorption, and reducing the risk of an excessively small diameter solder ribbon leading to increased transmission resistance, thereby improving the power of the photovoltaic module.

[0007] In one possible design, the cover plate has a first embossing on the side facing the adhesive film, the adhesive film includes a body and a second embossing, the second embossing is located on the side of the body facing the cover plate, and the first embossing and the second embossing are in concave-convex fit.

[0008] In one possible design, the cross-sectional shapes of the first embossing and the second embossing are serrated or wavy.

[0009] In one possible design, along the thickness direction of the photovoltaic module, the volume of the space between the cover plate and the solar cell is V = V1 + V2, where V1 is the volume of the second embossing located on one side of the main body, and V2 is the volume of the main body located on one side of the solar cell.

[0010]

[0011] Wherein, c is the height of the second embossing, and d is the minimum distance between the cover plate and the welding strip along the thickness direction of the photovoltaic module.

[0012] In one possible design, c satisfies 30μm≤c≤90μm.

[0013] In one possible design, the thickness of the cover plate is Z, and Z satisfies the following relationship:

[0014] d = 0.05Z

[0015] The basis weight y of a single layer of the adhesive film satisfies:

[0016]

[0017] Z satisfies 1.6mm≤Z≤3.2mm.

[0018] In one possible design, the basis weight y of the single-layer adhesive film, the diameter X of the solder strip, and the thickness Z of the cover plate satisfy the following relationship:

[0019]

[0020] In one possible design, the diameter X of the solder strip satisfies 0.2mm ≤ X ≤ 0.35mm.

[0021] In one possible design, the basis weight y of the single-layer adhesive film, the diameter X of the solder strip, and the thickness Z of the cover plate satisfy the following relationship:

[0022] 13.05 + 43.5Z + 870X - 58.123X 2 <,<43.2+48Z+960X-64.805X 2

[0023] The width b of the adhesive film is 1120 mm.

[0024] In one possible design, the basis weight y of the single-layer adhesive film satisfies 250 g / m². 2 ≤y≤520g / m2 The thickness H of a single layer of the adhesive film satisfies 350μm≤H≤550μm.

[0025] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description

[0026] Figure 1 This is a front view of the photovoltaic module provided in this application;

[0027] Figure 2 A side view of the photovoltaic module provided in this application;

[0028] Figure 3 for Figure 1 A magnified view of part I in the middle;

[0029] Figure 4 A graph showing the relationship between the basis weight of the single-layer encapsulant film of the photovoltaic module provided in this application and the diameter of the solder strip.

[0030] Figure label:

[0031] 1-Cover plate;

[0032] 11 - First Embossing;

[0033] 2- Adhesive film;

[0034] 21-Second embossing;

[0035] 22-Ontology;

[0036] 3-Battery cells;

[0037] 4-Solder strip.

[0038] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. Detailed Implementation

[0039] To better understand the technical solution of this application, the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0040] It should be understood that the described embodiments are merely some, not all, of the embodiments in this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0041] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0042] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0043] It should be noted that the directional terms such as "upper," "lower," "left," and "right" described in the embodiments of this application are used to describe the angles shown in the accompanying drawings and should not be construed as limiting the embodiments of this application. Furthermore, in the context, it should be understood that when it is mentioned that an element is connected "upper" or "lower" to another element, it can be directly connected to the other element "upper" or "lower," or indirectly connected to the other element "upper" or "lower" through an intermediate element.

[0044] This application provides a photovoltaic module, such as... Figure 1 , Figure 2 and Figure 3 As shown, the photovoltaic module includes two cover plates 1, two layers of encapsulant film 2, solar cells 3, and solder ribbons 4. The two cover plates 1 are distributed along the thickness direction of the photovoltaic module, and can be glass cover plates, back plates, or glass plates, respectively. That is, the two cover plates 1 are located on the outer side of the photovoltaic module along the thickness direction. The two layers of encapsulant film 2, solar cells 3, and solder ribbons 4 are all located between the two cover plates 1. The solder ribbons 4 connect two adjacent solar cells 3, thereby realizing the electrical connection of each solar cell 3. During the manufacturing process, the above components are laminated to form the photovoltaic module. After lamination, one layer of encapsulant film 2 connects the glass cover plate and the solar cell 3, and the other layer of encapsulant film 2 connects the back plate and the solar cell 3 or the glass plate and the solar cell 3.

[0045] When the thickness of the single-layer encapsulant film 2 is thin and the diameter X of the solder ribbon 4 is large, the thin encapsulant film 2 cannot protect the solar cell 3 during the lamination process, making the solar cell 3 susceptible to crushing or cracking during lamination. During the absorption of light by the photovoltaic module, when incident light shines on the surface of the photovoltaic module, the incident light passes through the cover plate 1 and the encapsulant film 2 to reach the surface of the solar cell 3. When the thickness of the encapsulant film 2 is thick and the diameter X of the solder ribbon 4 is small, the thicker encapsulant film 2 will reflect the incident light to some extent, affecting the absorption of light by the solar cell 3, resulting in a decrease in the photoelectric conversion efficiency of the photovoltaic module. Simultaneously, the smaller diameter X of the solder ribbon 4 will also increase the transmission resistance, further reducing the photoelectric conversion efficiency of the photovoltaic module.

[0046] To address the aforementioned technical problems, embodiments of this application achieve matching between the thickness of the adhesive film 2 and the size of the solder strip 4 by describing the qualitative or quantitative relationship between the film thickness and the solder strip size. For example... Figure 1 and Figure 2 As shown, two layers of adhesive film 2 are filled between the two cover plates 1. The volume V3 of a single layer of adhesive film 2 is obtained by subtracting the volume V4 of the battery cell 3 and the welding ribbon 4 from the volume V of the space between the cover plate 1 and the battery cell 3, that is, V3 = V - V4.

[0047] Among them, such as Figure 1 As shown, since the volume of battery cell 3 is small, it is neglected in the calculation, and the cross-section of the solder strip 4 is considered to be circular. πX 2 / 4 represents the cross-sectional area of ​​solder strip 4, where X is the diameter of solder strip 4. Additionally, as... Figure 2 As shown, along the length direction of the solder strip 4, the length dimension of the solder strip 4 is the same as the length dimension a of the adhesive film 2, as follows. Figure 1 In the embodiment shown, the number of battery strings formed by the single-layer battery cell 3 and the solder ribbon 4 is 6, and n is the number of main grids.

[0048] Based on this, we can obtain Thus obtain The basis weight y of the single-layer adhesive film 2 is:

[0049]

[0050] Where ρ is the density of film 2, and ρ satisfies 0.87 g / cm³. 3 ≤ρ≤0.96g / cm 3 For example, the density of film 2 can be 0.87 g / cm³. 3 0.88g / cm 3 0.89g / cm 3 0.9g / cm 3 0.92g / cm 3 0.94g / cm 30.96g / cm 3 wait.

[0051] In one specific embodiment, the material of the film 2 can be at least one of poly(ethylene octene) elastomer (POE) or ethylene vinyl acetate (EVA). POE material has good water vapor barrier and ion barrier capabilities, improving the sealing effect, and also has good anti-aging properties, thus improving the service life of the photovoltaic module. EVA material allows short-wavelength incident light to pass through more smoothly, improving the absorption efficiency of the solar cell 3 for incident light.

[0052] Therefore, when the basis weight y of the single-layer adhesive film 2 and the diameter X of the solder strip 4 satisfy the above formula (1), their functional relationship is as follows: Figure 4 As shown, this ensures that the basis weight y of the single-layer encapsulant film 2 and the diameter X of the solder ribbon 4 are properly matched. This reduces the risk of the encapsulant film being too thin (too small) while the solder ribbon diameter is too large, thus allowing the encapsulant film 2 to protect the solar cell 3 during lamination, reducing the risk of damaging the solar cell 3 and improving its reliability and lifespan. Simultaneously, it also reduces the risk of the encapsulant film being too thick (too large) while the solder ribbon diameter is too small, thus reducing the impact of an excessively thick encapsulant film 2 on the solar cell 3's light absorption and reducing the risk of an excessively small solder ribbon 4 causing increased transmission resistance, thereby improving the power of the photovoltaic module.

[0053] In one specific embodiment, two adjacent solar cells 3 are connected together by a solder strip 4 to form a solar cell string, and the photovoltaic module may include one or more solar cell strings. For example, the number of solar cell strings may be 1, 2, 3, 4, 5, 6, 7, 8, 9, etc. When there are multiple solar cell strings, the multiple solar cell strings are arranged at intervals and electrically connected by series and / or parallel connection.

[0054] Among them, such as Figure 1 , Figure 2 and Figure 3 As shown, the cover plate 1 has a first embossing 11 on the side facing the adhesive film 2. The adhesive film 2 includes a body 22 and a second embossing 21. The second embossing 21 is located on the side of the body 22 facing the cover plate 1. The first embossing 11 and the second embossing 21 are in concave-convex fit.

[0055] In this embodiment, the first embossing 11 and the second embossing 21 make the surfaces where the cover plate 1 and the adhesive film 2 connect uneven surfaces. The cover plate 1 and the adhesive film 2 can be tightly connected through the uneven first embossing 11 and the second embossing 21, increasing the connection area between the cover plate 1 and the adhesive film 2, thereby improving the connection stability between the cover plate 1 and the adhesive film 2. After lamination, the body 22 of the adhesive film 2 is used to wrap the solar cell 3 and the solder ribbon 4 to achieve encapsulation. At the same time, when the photovoltaic module is irradiated by a light source, the incident light will pass through the cover plate 1 and the adhesive film 2 and be incident on the surface of the solar cell 3. Some of the incident light will be reflected by the solar cell 3. The reflected incident light can undergo diffuse reflection on the first embossing 11 of the cover plate 1, so that the reflected incident light is reflected again by the first embossing 11 to the surface of the solar cell 3, thereby improving the light absorption efficiency of the solar cell 3.

[0056] Specifically, such as Figure 1 , Figure 2 and Figure 3 As shown, the cross-sectional shape of the first embossing 11 and the second embossing 21 is serrated or wavy. The serrated or wavy embossing structure has the advantages of simple structure and convenient processing. At the same time, the serrated or wavy shape is conducive to diffuse reflection of light, thereby improving the optical efficiency of the photovoltaic module.

[0057] Specifically, such as Figure 1 , Figure 2 and Figure 3 As shown, along the thickness direction of the photovoltaic module, the volume of the space between the cover plate 1 and the solar cell 3 is V = V1 + V2, where V1 is the volume of the second embossing 21 located on one side of the body 22, and V2 is the volume of the body 22 located on one side of the solar cell 3. Figure 1 , Figure 2 and Figure 3 As shown, the cross-sectional shape of the second embossing 21 is approximately triangular, and the cross-sectional shape of the body 22 is approximately rectangular.

[0058] Therefore, we obtain V2=(d+X)0b.

[0059] Based on this, the above formula (1) is:

[0060]

[0061] Where c is the height of the second embossing 21, and d is the minimum distance between the cover plate 1 and the welding strip 4 along the thickness direction of the photovoltaic module.

[0062] Specifically, c satisfies 30μm≤c≤90μm, where c can be 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, etc. When the height of the second embossing 21 is too small (e.g., c is less than 30μm), the height of the first embossing 11 is also too small, resulting in the first embossing 11 and the second embossing 21 failing to increase the contact area between the cover plate and the adhesive film, reducing the connection stability between the cover plate 1 and the adhesive film 2. Furthermore, the excessively small embossing height affects the diffuse emission of incident light within the cover plate 1 and the adhesive film 2, reducing the light absorption efficiency of the solar cell 3. When the height of the second embossing 21 is too large (e.g., c is greater than 90μm), the height of the first embossing 11 is also too large, resulting in both the cover plate 1 and the adhesive film 2 being too thick. An excessively thick adhesive film 2 will affect the absorption performance of the solar cell 3 for incident light. Therefore, when the height c of the second embossing 21 satisfies 30μm≤c≤90μm, the thickness of the cover plate 1 and the film 2 is moderate, and the absorption performance of the battery cell 3 for incident light is optimal.

[0063] Specifically, the thickness of the cover plate 1 is Z. Typically, the minimum distance between the cover plate 1 and the solder strip 4 along the thickness direction of the photovoltaic module can be d, and d satisfies:

[0064] d=0.05Z (3)

[0065] Based on this, the above formula (2) can be specifically defined as follows:

[0066]

[0067] Where Z satisfies 1.6mm≤Z≤3.2mm.

[0068] In this embodiment of the application, the thickness Z of the cover plate 1 can be 1.6mm, 1.9mm, 2.1mm, 2.3mm, 2.6mm, 2.9mm, 3.2mm, etc.

[0069] When the thickness of cover plate 1 is too small (e.g., Z < 1.6 mm), the protective effect of cover plate 1 on the solar cell 3 and solder ribbon 4 is weakened, resulting in low reliability and structural strength of the photovoltaic module. When the thickness of cover plate 1 is too large (e.g., Z > 3.2 mm), the overall thickness and weight of the photovoltaic module are excessive, affecting installation. Furthermore, an excessively thick cover plate 1 has reduced light transmittance, affecting the absorption rate of incident light by the solar cell 3. Therefore, when the thickness Z of cover plate 1 satisfies 1.6 mm ≤ Z ≤ 3.2 mm, cover plate 1 provides protection for the solar cell 3 and solder ribbon 4 while maintaining high light transmittance, which is beneficial for improving the absorption performance of incident light by the solar cell 3. Specifically, the thickness Z of cover plate 1 is preferably 2 mm ≤ Z ≤ 3.2 mm to achieve the optimal range of light transmittance.

[0070] Specifically, based on the above formula (4), the following formula can be obtained:

[0071]

[0072] That is, the basis weight y of the single-layer encapsulant film 2, the diameter X of the solder ribbon 4, and the thickness Z of the cover plate 1 satisfy the above formula (5). When the basis weight y of the single-layer encapsulant film 2, the diameter X of the solder ribbon 4, and the thickness Z of the cover plate 1 are matched, the photovoltaic module has a high absorption efficiency for incident light, which can improve the photoelectric conversion capability of the photovoltaic module. At the same time, when the photovoltaic module is laminating, the cell 3 will not be damaged by high pressure, thus improving the yield of the photovoltaic module.

[0073] The diameter X of the solder ribbon 4 satisfies 0.2mm ≤ X ≤ 0.35mm. Specifically, the diameter X of the solder ribbon 4 can be 0.2mm, 0.23mm, 0.25mm, 0.27mm, 0.3mm, 0.33mm, 0.35mm, etc. When the diameter of the solder ribbon 4 is too small (e.g., X < 0.2mm), the transmission resistance increases, reducing the efficiency of the photovoltaic module; when the diameter of the solder ribbon 4 is too large (e.g., X > 0.35mm), the pressure on the solar cell 3 is too high, and the solar cell 3 is at risk of being crushed or cracked during the lamination process. Therefore, when the diameter X of the solder ribbon 4 satisfies 0.2mm ≤ X ≤ 0.35mm, the working performance of the photovoltaic module can be improved while reducing the risk of damage to the solar cell 3. Specifically, the diameter X of the solder ribbon 4 is preferably 0.26mm ≤ X ≤ 0.35mm to ensure optimal current transmission performance.

[0074] In one specific embodiment, by substituting the maximum and minimum values ​​of the height c of the second embossing 21, the width b of the adhesive film 2, the number of gratings n, and the density ρ of the adhesive film 2 into the above formula (5), the basis weight y of the single-layer adhesive film 2, the diameter X of the solder ribbon 4, and the thickness Z of the cover plate 1 can be obtained, which satisfy the following relationship:

[0075] 13.05 + 43.5Z + 870X - 58.123X 2 <y<43.2+48Z+960X-64.805X 2 (6)

[0076] The width b of the adhesive film 2 is 1120 mm.

[0077] In this embodiment, when the basis weight y of the single-layer adhesive film 2, the diameter X of the solder ribbon 4, and the thickness Z of the cover plate 1 satisfy the above formula (6), the basis weight y of the adhesive film 2 matches the diameter X of the solder ribbon 4, thereby improving the absorption efficiency of the photovoltaic module for incident light, improving the photoelectric conversion capability, and at the same time having a high sealing effect and protection function, thereby improving the service life of the photovoltaic module.

[0078] Specifically, the basis weight y of the single-layer adhesive film 2 satisfies 250 g / m².2 ≤y≤520g / m 2 The thickness H of the single-layer adhesive film 2 satisfies 350μm≤H≤550μm. According to the above formula (6), by substituting the maximum and minimum values ​​of the diameter X of the welding strip 4 and the thickness Z of the cover plate 1 into formula (6), the basis weight y of the single-layer adhesive film 2 can be obtained, and thus the thickness of the single-layer adhesive film 2 can be obtained.

[0079] Specifically, the basis weight y of the single-layer adhesive film 2 can be 250 g / m³. 2 300g / m 2 350g / m 2 400g / m 2 450g / m 2 500g / m 2 520g / m 2 The thickness H of the single-layer adhesive film 2 can be 350μm, 370μm, 400μm, 450μm, 500μm, 250μm, 550μm, etc.

[0080] When the basis weight y of the single-layer adhesive film 2 is too small (e.g., y is less than 250 g / m²), 2 When the thickness H is too small (e.g., H less than 350 μm), the protective effect of the single-layer encapsulant film 2 on the solar cell 3 is reduced, making the solar cell 3 more susceptible to damage. Simultaneously, the sealing performance of the photovoltaic module decreases, allowing moisture to easily enter the module and cause the solar cell 3 to fail. Conversely, when the basis weight y of the single-layer encapsulant film 2 is too large (e.g., y greater than 520 g / m³), the protective effect is further reduced. 2 When the thickness H is too large (e.g., H is greater than 550μm), it will affect the efficiency of the solar cell 3 in absorbing incident light. At the same time, the overall thickness and weight of the photovoltaic module will be too large, affecting the installation.

[0081] Therefore, when the basis weight y of the single-layer adhesive film 2 satisfies 250 g / m 2 ≤y≤520g / m 2 When the thickness H satisfies 350μm≤H≤550μm, it not only provides a better encapsulation effect and improves the protection of the photovoltaic module's interior, but also helps improve the absorption efficiency of incident light by the solar cell 3, while reducing the overall weight of the photovoltaic module, facilitating transportation and installation. Specifically, the basis weight y of the single-layer encapsulant film 2 is preferably 320g / m². 2 ≤y≤520g / m 2 This is to ensure that the photovoltaic module achieves its optimal power output.

[0082] Table 1 below shows the defects and power of photovoltaic modules for different solder strip diameters X, cover plate thicknesses Z, and single-layer encapsulant weights y.

[0083]

[0084] Table 1

[0085] When the values ​​of the diameter X of the solder strip 4, the thickness Z of the cover plate 1, and the basis weight y of the single-layer adhesive film 2 are all outside the range of this application, for example, when the solder strip diameter X is 0.14 mm, the cover plate thickness Z is 1.1 mm, and the basis weight y of the single-layer adhesive film is 193 g / m³, the application range is 193 g / m³. 2 At that time, the photovoltaic module had a zero microcrack rate of 91%, a bubble formation probability of 26%, and a power output below 563; when the solder strip diameter X was 0.16 mm, the cover plate thickness Z was 1.3 mm, and the single-layer encapsulant film basis weight y was 210 g / m³. 2 At that time, the photovoltaic module had a zero microcrack rate of 93%, a bubble formation probability of 24%, and a power output below 564 kW; when the solder strip diameter X was 0.18 mm, the cover plate thickness Z was 1.5 mm, and the single-layer encapsulant film basis weight y was 233 g / m³. 2 At that time, the zero microcrack rate of the photovoltaic module was 95%, the probability of bubble formation was 22%, and the photovoltaic module power was less than 565. Therefore, when the values ​​of the diameter X of the solder strip 4, the thickness Z of the cover plate 1, and the basis weight y of the single-layer encapsulant film 2 are all outside the range of this application, the photovoltaic module has a higher probability of cracking (lower zero microcrack rate, for example, less than 95%), a higher probability of bubble formation (for example, more than 20%), and a lower overall photovoltaic module power (for example, less than 565).

[0086] When the values ​​of the solder strip diameter X, the cover plate thickness Z, and the basis weight y of the single-layer adhesive film 2 are within the range of this application, for example, when the solder strip diameter X is 0.2 mm, the cover plate thickness Z is 1.6 mm, and the single-layer adhesive film basis weight y is 254 g / m², the solder strip diameter X is 0.2 mm, the cover plate thickness Z is 1.6 mm, and the single-layer adhesive film basis weight y is 254 g / m². 2 At that time, the photovoltaic module had a zero microcrack rate of 98%, a bubble formation probability of 2%, and a power output higher than 565W; when the solder strip diameter X was 0.22mm, the cover plate thickness Z was 1.7mm, and the single-layer encapsulant film basis weight y was 282g / m³. 2 At that time, the photovoltaic module had a zero microcrack rate of 98.41%, a bubble formation probability of 1.8%, and a power output higher than 565.3 kW; when the solder strip diameter X was 0.24 mm, the cover plate thickness Z was 1.8 mm, and the single-layer encapsulant film basis weight y was 311 g / m³. 2 At that time, the photovoltaic module had a zero microcrack rate of 98.63%, a bubble generation probability of 1.3%, and a photovoltaic module power of over 565.4. Therefore, when the values ​​of the diameter X of the solder strip 4, the thickness Z of the cover plate 1, and the basis weight y of the single-layer encapsulant 2 are within the range of this application, the photovoltaic module has a low probability of cracking (high zero microcrack rate, for example, over 98%), a low probability of bubble generation (for example, less than 2%), and a high overall photovoltaic module power (for example, over 565).

[0087] When the values ​​of the solder strip diameter X, the cover plate thickness Z, and the basis weight y of the single-layer adhesive film 2 are within the preferred range of this application, for example, when the solder strip diameter X is 0.26 mm, the cover plate thickness Z is 3.2 mm, and the single-layer adhesive film basis weight y is 374 g / m³, the desired values ​​are as follows: 2 At that time, the photovoltaic module had a zero microcrack rate of 99.89%, a bubble formation probability of 0.30%, and a power output higher than 565.5 kW. The solder strip diameter X was 0.28 mm, the cover plate thickness Z was 2.7 mm, and the single-layer encapsulant film basis weight y was 437 g / m³. 2 At that time, the photovoltaic module had a zero microcrack rate of 99.91%, a bubble formation probability of 0.26%, and a photovoltaic module power output higher than 565.6 kW. The solder strip diameter X was 0.3 mm, the cover plate thickness Z was 2.9 mm, and the single-layer encapsulant film basis weight y was 513 g / m³. 2 At that time, the photovoltaic module has a zero microcrack rate of 99.93%, a bubble generation probability of 0.23%, and a photovoltaic module power of over 565.7. Therefore, when the values ​​of the diameter X of the solder strip 4, the thickness Z of the cover plate 1, and the basis weight y of the single-layer adhesive film 2 are within the preferred range of this application, the photovoltaic module has a lower probability of cracking (higher zero microcrack rate, for example, over 99.5%), a lower probability of bubble generation (for example, less than 0.5%), and a higher overall photovoltaic module power (for example, over 565.5).

[0088] In summary, when the values ​​of the diameter X of the solder strip 4, the thickness Z of the cover plate 1, and the basis weight y of the single-layer adhesive film 2 are within the preferred range of this application, the three components can achieve a suitable matching relationship, reduce the possibility of photovoltaic module defects during production, and effectively improve the power of the photovoltaic module and the product quality of the photovoltaic module.

[0089] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. 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 module, characterized in that, The photovoltaic module includes: Two cover plates (1) are distributed along the thickness direction of the photovoltaic module; The battery cell (3) and the solder strip (4) are located between the two cover plates (1), and the solder strip (4) connects the two adjacent battery cells (3). Two layers of adhesive film (2) are located between two cover plates (1), and each cover plate (1) and the battery cell (3) are connected by one layer of adhesive film (2); The basis weight y of the single-layer adhesive film (2) and the diameter X of the solder strip (4) satisfy the following relationship: ； Wherein, V is the volume of the space between the cover plate (1) and the battery cell (3), a is the length of the adhesive film (2), b is the width of the adhesive film (2), and n is the number of main grids of the photovoltaic module; ρ is the density of the adhesive film, and ρ satisfies 0.87 g / cm³. 3 ≤ρ≤0.96g / cm 3 .

2. The photovoltaic module according to claim 1, characterized in that, The cover plate (1) has a first embossing (11) on the side facing the adhesive film (2). The adhesive film (2) includes a body (22) and a second embossing (21). The second embossing (21) is located on the side of the body (22) facing the cover plate (1). The first embossing (11) and the second embossing (21) are in concave-convex fit.

3. The photovoltaic module according to claim 2, characterized in that, The cross-sectional shapes of the first embossing (11) and the second embossing (21) are sawtooth or wavy.

4. The photovoltaic module according to claim 2, characterized in that, Along the thickness direction of the photovoltaic module, the volume of the space between the cover plate (1) and the solar cell (3) is V = V1 + V2, where V1 is the volume of the second embossing (21) located on one side of the body (22), and V2 is the volume of the body (22) located on one side of the solar cell (3). ； Wherein, c is the height of the second embossing (21), and d is the minimum distance between the cover plate (1) and the welding strip (4) along the thickness direction of the photovoltaic module.

5. The photovoltaic module according to claim 4, characterized in that, c satisfies 30μm≤c≤90μm.

6. The photovoltaic module according to claim 4, characterized in that, The thickness of the cover plate (1) is Z, and Z satisfies the following relationship: ； The basis weight y of the single-layer adhesive film (2) satisfies: ； Z satisfies 1.6mm≤Z≤3.2mm.

7. The photovoltaic module according to claim 6, characterized in that, The basis weight y of the single-layer adhesive film (2), the diameter X of the solder strip (4), and the thickness Z of the cover plate (1) satisfy the following relationship: 。 8. The photovoltaic module according to claim 7, characterized in that, The diameter X of the welding strip (4) satisfies 0.2mm≤X≤0.35mm.

9. The photovoltaic module according to claim 8, characterized in that, The basis weight y of the single-layer adhesive film (2), the diameter X of the solder strip (4), and the thickness Z of the cover plate (1) satisfy the following relationship: ； The width b of the adhesive film (2) is 1120 mm.

10. The photovoltaic module according to any one of claims 1-9, characterized in that, The basis weight y of the single-layer adhesive film (2) satisfies 250 g / m 2 ≤y≤520g / m 2 The thickness H of the single-layer adhesive film (2) satisfies 350μm≤H≤550μm.

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