CN118136707A - Photovoltaic module - Google Patents

Abstract

The invention provides a photovoltaic module, the encapsulation frame of the photovoltaic module comprises: sequentially laminating an upper glass substrate, a first connecting adhesive layer, a sealing adhesive layer, a second connecting adhesive layer and a lower glass substrate which are hermetically bonded along the thickness direction of the photovoltaic module; the bonding strength of the first connection adhesive layer/the second connection adhesive layer and the inner surfaces of the upper glass substrate/the lower glass substrate is greater than that of the sealing adhesive layer and the inner surfaces of the upper glass substrate/the lower glass substrate. According to the photovoltaic module, the connecting adhesive layer is arranged between the glass substrate and the sealing adhesive layer, so that the sealing adhesive layer is fixedly adhered to the glass substrate through the connecting adhesive layer, gaps are not easy to generate between the connecting adhesive layer and the glass substrate, the reliability of connection between the sealing adhesive layer and the glass substrate is improved, and the sealing effect of the photovoltaic module is improved.

Description

Photovoltaic panels

Technical Field

The present invention relates to the technical field of photovoltaic modules, and in particular to a photovoltaic module.

Background technique

With the development of photovoltaic cell technology, the requirements for the sealing performance of photovoltaic modules are getting higher and higher. In the existing technology, butyl rubber is usually used as the waterproof material of photovoltaic modules. Butyl rubber is a copolymer of isobutylene and a small amount of isoprene. It has good thermal stability and chemical stability and plays an important role in the encapsulation of solar cells that are sensitive to water vapor.

In the prior art, butyl adhesive is usually applied directly on the glass surface so that the butyl adhesive is directly bonded to the glass surface. However, the bonding strength between the butyl adhesive and the glass surface is weak, and it is easy to debond, so that a gap is formed between the butyl adhesive and the glass surface, causing water vapor to quickly enter the module through the gap, affecting the sealing effect of the photovoltaic module.

Summary of the invention

The present invention aims to at least solve the problem in the prior art that the bonding force between butyl rubber and the glass surface is weak and debonding is easy to occur, and proposes a photovoltaic module.

In order to achieve the purpose of the present invention, a photovoltaic module is provided, and the packaging frame of the photovoltaic module includes: an upper glass substrate, a first connecting adhesive layer, a sealing adhesive layer, a second connecting adhesive layer and a lower glass substrate which are stacked and sealed in sequence along the thickness direction of the photovoltaic module; the bonding strength between the first connecting adhesive layer/the second connecting adhesive layer and the inner surface of the upper glass substrate/the lower glass substrate is greater than the bonding strength between the sealing adhesive layer and the inner surface of the upper glass substrate/the lower glass substrate.

Furthermore, the aging resistance of the first connecting adhesive layer/the second connecting adhesive layer is stronger than the aging resistance of the sealing adhesive layer.

Furthermore, the sealing adhesive layer is a butyl adhesive layer; the first connecting adhesive layer/the second connecting adhesive layer is any one of a silicone adhesive layer, a polyurethane adhesive layer, a POE adhesive film layer, an EVA adhesive film layer, a PVB adhesive film layer or an EPE adhesive film layer.

Furthermore, the first connecting adhesive layer/the second connecting adhesive layer is as wide as the sealing adhesive layer, and the width thereof is in the range of 8-12 mm.

Further, the thickness of the first connecting adhesive layer/the second connecting adhesive layer is H1, the distance between the upper glass substrate and the lower glass substrate is H2, and H1:H2<1/7.

Furthermore, the first connecting adhesive layer/the second connecting adhesive layer is a POE adhesive film layer, and H1 is less than 0.05 mm.

Furthermore, the first connecting adhesive layer/the second connecting adhesive layer is a silicone adhesive layer, H1＜

0.04mm.

Furthermore, the first connecting adhesive layer/the second connecting adhesive layer is an EVA film layer, and H1 is less than 0.05 mm.

Furthermore, the first connecting adhesive layer/the second connecting adhesive layer is a PVB adhesive film layer, and H1 is less than 0.05 mm.

Furthermore, the first connecting adhesive layer/the second connecting adhesive layer is an EPE adhesive film layer, H1

＜0.07mm.

Furthermore, the photovoltaic module also includes: a cell layer, which is arranged between the upper glass substrate and the lower glass substrate, the sealant layer, the first connecting adhesive layer and the second connecting adhesive layer are all arranged around the periphery of the cell layer, and the upper glass substrate, the lower glass substrate, the first connecting adhesive layer, the second connecting adhesive layer and the sealant layer form a sealed space for sealing the cell layer.

The photovoltaic module of the present invention provides a connecting glue layer between the glass substrate and the sealant layer so that the sealant layer is bonded and fixed to the glass substrate through the connecting glue layer. It is less likely to generate a gap between the connecting glue layer and the glass substrate, thereby improving the reliability of the connection between the sealant layer and the glass substrate and improving the sealing effect of the photovoltaic module.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the structure of a photovoltaic module in the related art;

FIG. 2 is a schematic diagram of the structure of a cell sheet adhesive film combination layer of a photovoltaic module in the related art;

FIG3 is a perspective view of a photovoltaic module according to Embodiment 1 of the present invention;

FIG4 is a side cross-sectional view of a photovoltaic module according to Embodiment 1 of the present invention;

List of reference numerals:

11. upper glass substrate; 12. lower glass substrate; 20. sealing adhesive layer; 31. first connecting adhesive layer; 32. second connecting adhesive layer; 40. battery cell layer; 50. encapsulation adhesive film.

Detailed ways

In order to enable those skilled in the art to better understand the technical solution of the present invention, the photovoltaic module provided by the present invention is described in detail below with reference to the accompanying drawings.

With the development of photovoltaic cell technology, the requirements for the sealing performance of photovoltaic modules are getting higher and higher. In the existing technology, butyl rubber is usually used as the waterproof material of photovoltaic modules. Butyl rubber is a copolymer of isobutylene and a small amount of isoprene. It has good thermal stability and chemical stability and plays an important role in the encapsulation of solar cells that are sensitive to water vapor.

Among the existing photovoltaic modules, heterojunction modules are highly favored. As shown in FIG1 , the existing heterojunction modules generally include: a first glass 1, a cell film combination layer 2, a second glass 3 and a butyl rubber ring 4. Among them, the first glass 1, the cell film combination layer 2 and the second glass 3 are arranged in sequence from top to bottom, the butyl rubber ring 4 is arranged around the cell film combination layer 2 and the upper and lower sides of the butyl rubber ring 4 are directly bonded to the first glass 1 and the second glass 3, and the cell film combination layer 2 is surrounded, thereby playing a waterproof role. As shown in FIG2 , the internal structure of the cell film combination layer 2 is shown in FIG2 , which includes a cell layer 5 and a packaging film 6, and the cell layer 5 is bonded and fixed to the first glass 1 and the second glass 3 through the packaging film 6.

Among them, the encapsulation film 6 is mainly divided into four types, namely transparent EVA (ethylene-vinyl acetate copolymer) film, transparent PVB (polyvinyl butyral) film, POE (polyolefin elastomer) film, and co-extruded EPE film (EPE co-extruded film is extruded from EVA and POE resin through a co-extrusion process).

However, after a period of use, the sealing effect of the photovoltaic module encapsulated in the above manner will decrease, resulting in water vapor entering the interior. After research, it was found that the reason for the decrease in sealing effect is that the connection between butyl rubber and glass is not as reliable as technicians in the field believe. This is because, although the butyl rubber material itself has excellent waterproof effect, butyl rubber is a non-polar material, which is incompatible with the polar Si-OH on the glass surface. This leads to a large difference in surface energy between the two, not only poor bonding strength, but also poor aging resistance (aging resistance refers to the reliability of bonding between the bonding material and the glass surface over time after bonding, that is, the duration of bonding between the bonding material and the glass surface. If the aging resistance is strong, it means that the bonding between the bonding material and the glass surface lasts for a long time, and the bonding material is not easy to separate from the glass surface after long-term use, and the reliability is strong; if the aging resistance is weak, it means that the bonding between the bonding material and the glass surface lasts for a short time, and after a period of use, the bonding material is easy to separate from the glass surface, and the reliability is poor). From the long-term reliability of photovoltaic modules, the weak bonding and aging resistance of butyl rubber to glass is a potential risk.

That is to say, during long-term use, due to the weak adhesion and aging resistance of butyl rubber to the glass surface, debonding is likely to occur between the butyl rubber ring 4 and the first glass 1, and between the butyl rubber ring 4 and the second glass 3 in Figure 1, so that gaps are formed between the butyl rubber ring 4 and the surfaces of the first glass 1 and the second glass 3, causing water vapor to quickly enter the interior of the component through the gaps, affecting the sealing effect of the photovoltaic component, and ultimately causing serious interface water penetration, thereby affecting the component power.

In order to solve the above problems, an embodiment of the present invention as shown in Figure 3 discloses a photovoltaic module, and the packaging frame of the photovoltaic module includes: an upper glass substrate 11, a first connecting adhesive layer 31, a sealing adhesive layer 20, a second connecting adhesive layer 32 and a lower glass substrate 12 which are stacked and sealed in sequence along the thickness direction of the photovoltaic module; the bonding strength between the first connecting adhesive layer 31 and the inner surface of the upper glass substrate 11 is greater than the bonding strength between the sealing adhesive layer 20 and the inner surface of the upper glass substrate 11, and the bonding strength between the second connecting adhesive layer 32 and the inner surface of the lower glass substrate 12 is greater than the bonding strength between the sealing adhesive layer 20 and the inner surface of the lower glass substrate 12.

The photovoltaic module of the present invention provides a connecting glue layer between the glass substrate and the sealing glue layer, so that the sealing glue layer is bonded and fixed to the glass substrate through the connecting glue layer. Since the bonding strength between the connecting glue layer and the inner surface of the glass substrate is greater than the bonding strength between the sealing glue layer and the inner surface of the glass substrate, it is less likely to generate a gap between the connecting glue layer and the glass substrate under the action of external force, thereby improving the reliability of the connection between the sealing glue layer and the glass substrate and improving the sealing effect of the photovoltaic module.

Further, the aging resistance of the first connecting adhesive layer 31 is stronger than that of the sealing adhesive layer 20, and the aging resistance of the second connecting adhesive layer 32 is stronger than that of the sealing adhesive layer 20. In other words, the bonding duration of the first connecting adhesive layer 31 to the inner surface of the upper glass substrate 11 is longer than the bonding duration of the sealing adhesive layer 20 to the inner surface of the upper glass substrate 11, and the bonding duration of the second connecting adhesive layer 32 to the inner surface of the lower glass substrate 12 is longer than the bonding duration of the sealing adhesive layer 20 to the inner surface of the lower glass substrate 12.

The photovoltaic module of the present invention provides a connecting glue layer between the glass substrate and the sealant layer. Since the connecting glue layer has stronger aging resistance than the sealant layer, that is, the bonding duration between the connecting glue layer and the inner surface of the glass substrate is longer than the bonding duration between the sealant layer and the inner surface of the glass substrate, in the time dimension, the bonding between the connecting glue layer and the glass substrate is more durable and less likely to separate and produce a gap, thereby improving the reliability of the connection between the sealant layer and the glass substrate and improving the sealing effect of the photovoltaic module.

Specifically, as shown in FIG. 4 , in this embodiment, the lower glass substrate 12 is arranged in parallel with the upper glass substrate 11, and the sealant layer 20 is located between the upper glass substrate 11 and the lower glass substrate 12. The upper glass substrate 11 has a first bonding surface facing the sealant layer 20, and the sealant layer 20 has a second bonding surface parallel to the first bonding surface; the first connecting adhesive layer 31 is arranged between the first bonding surface and the second bonding surface, and the first bonding surface of the upper glass substrate 11 is bonded and fixed to the second bonding surface of the sealant layer 20 through the first connecting adhesive layer 31, wherein the bonding strength and bonding duration between the second bonding surface of the first connecting adhesive layer 31 and the first bonding surface of the upper glass substrate 11 are greater than the bonding strength and bonding duration between the sealant layer 20 and the upper glass substrate 11. Similarly, the lower glass substrate 12 has a third bonding surface facing the sealant layer 20, and the sealant layer 20 has a fourth bonding surface parallel to the third bonding surface; the second connecting adhesive layer 32 is arranged between the third bonding surface and the fourth bonding surface, and the third bonding surface of the lower glass substrate 12 is bonded and fixed to the fourth bonding surface of the sealant layer 20 through the second connecting adhesive layer 32, wherein the bonding strength and bonding duration between the fourth bonding surface of the second connecting adhesive layer 32 and the third bonding surface of the lower glass substrate 12 are greater than the bonding strength and bonding duration between the sealant layer 20 and the lower glass substrate 12.

During assembly, the second connecting adhesive layer 32 can be first coated on the third bonding surface of the lower glass substrate 12, and then the fourth bonding surface of the sealing layer 20 can be attached to the second connecting adhesive layer 32, so that the bonding between the lower glass substrate 12 and the sealing layer 20 is achieved through the second connecting adhesive layer 32. After the battery cell layer 40 is assembled, the first connecting adhesive layer 31 is set on the second bonding surface of the sealing layer 20, and the first bonding surface of the upper glass substrate 11 is bonded to the first connecting adhesive layer 31 to complete the assembly. Since the bonding strength and bonding duration between the first connecting adhesive layer 31/the second connecting adhesive layer 32 and the upper glass substrate 11/the lower glass substrate 12 are greater than the bonding strength and bonding duration between the sealant layer 20 and the upper glass substrate 11/the lower glass substrate 12 directly, the bonding method of the sealant layer 20 and the upper glass substrate 11/the lower glass substrate 12 through the first connecting adhesive layer 31/the second connecting adhesive layer 32 is more firm and reliable than that of the sealant layer 20 and the upper glass substrate 11/the lower glass substrate 12 directly. In addition, due to the strong aging resistance, the bonding duration between the upper glass substrate 11/the lower glass substrate 12 and the sealant layer 20 is longer, and gaps are not easily generated during long-term use, thereby reducing the risk of water vapor entering the interior of the component and improving the stability of the component operating power.

The photovoltaic module of the present invention provides a connecting glue layer between the glass substrate and the sealant layer so that the sealant layer is bonded and fixed to the glass substrate through the connecting glue layer. It is less likely to generate a gap between the connecting glue layer and the glass substrate, thereby improving the reliability of the connection between the sealant layer and the glass substrate and improving the sealing effect of the photovoltaic module.

It should be noted that in this embodiment, by respectively providing the first connecting adhesive layer 31 and the second connecting adhesive layer 32 on both sides of the sealing adhesive layer 20, the connection between the sealing adhesive layer 20 and the upper glass substrate 11 and the lower glass substrate 12 is more secure and reliable, thereby achieving reliable sealing. However, this is not restrictive, and in some other embodiments not shown in the figure, only the first connecting adhesive layer 31 or the second connecting adhesive layer 32 may be provided, which also falls within the protection scope of the present invention.

As shown in FIG3 and FIG4, the photovoltaic module further includes: a cell layer 40, the cell layer 40 is arranged between the upper glass substrate 11 and the lower glass substrate 12, and the sealant layer 20, the first connecting glue layer 31 and the second connecting glue layer 32 are all arranged around the outer periphery of the cell layer 40. That is to say, in this embodiment, the cell layer 40 is surrounded by the sealant layer 20, the first connecting glue layer 31 and the second connecting glue layer 32, and the upper glass substrate 11, the lower glass substrate 12, the first connecting glue layer 31, the second connecting glue layer 32 and the sealant layer 20 together form a sealed space, and the cell layer 40 is located in the sealed space, so as to achieve isolation of the cell layer 40 from the outside, and by providing the annular sealant layer 20 and the connecting glue layer, the connection between the sealant layer 20 and the upper glass substrate 11 and the lower glass substrate 12 is made tighter, the tightness of the connection is ensured in the circumferential direction, and a gap is prevented from appearing between the sealant layer 20 and the upper glass substrate 11 or the lower glass substrate 12, so that the sealed space is connected with the outside, and the sealing of the sealed space can be effectively improved.

It can be understood that the sealed space is filled with a packaging film 50 to bond the battery layer 40 to the upper glass substrate 11, the lower glass substrate 12 and the sealant layer 20 respectively, so that the battery layer 40, the sealant layer 20 and the glass substrate are fixedly connected to form a whole, thereby improving the reliability of the connection.

It can also be understood that in order to improve the connection reliability between the first connecting adhesive layer 31, the second connecting adhesive layer 32 and the sealing adhesive layer 20, the width D of the first connecting adhesive layer 31 is equal to the width of the sealing adhesive layer 20, and its width range is 8-12mm. By setting the first connecting adhesive layer 31 to be equal to the width of the sealing adhesive layer 20, it can be ensured that the contact area between the first connecting adhesive layer 31 and the sealing adhesive layer 20 and the upper glass substrate 11 is maximized, thereby ensuring the reliability of the connection. At the same time, if the width D is less than 8mm, the width of the sealing adhesive layer 20 and the first connecting adhesive layer 31 is too small, making it easier for external water vapor to penetrate, resulting in a decrease in sealing performance. If the width D is greater than 12mm, it will cause the sealing adhesive layer 20 and the first connecting adhesive layer 31 to overflow, which not only wastes materials and increases the cost, but also affects the appearance. Therefore, the width D ranges between 8-12mm.

It should be noted that, in this embodiment, the width of the second connecting adhesive layer 32 is the same as the width of the first connecting adhesive layer 31, but this is not restrictive. In some other embodiments not shown in the figure, the width of the first connecting adhesive layer 31 may be set to D or the width of the second connecting adhesive layer 32 may be set to D, which also falls within the scope of protection of the present invention.

It should be noted that, in this embodiment, the sealing adhesive layer 20 is a butyl adhesive layer, and the first connecting adhesive layer 31 and the second connecting adhesive layer 32 can be made of a material with good bonding strength to glass, that is, the bonding strength between the material and the glass is greater than the bonding strength between the butyl adhesive and the glass, and the aging resistance is stronger, such as: a silicone adhesive layer, a polyurethane adhesive layer. The connecting adhesive layer can also be a POE adhesive film layer, an EVA adhesive film layer, a PVB adhesive film layer or an EPE adhesive film layer and an organic silicone layer.

It should also be noted that the sealant layer 20 is the main waterproof structure. If the thickness of the first connecting adhesive layer 31 and the second connecting adhesive layer 32 is large, then the first connecting adhesive layer 31 and the second connecting adhesive layer 32 themselves will become a major way for water to penetrate. Although the adhesion is improved, the waterproof effect will be deteriorated. Therefore, the thickness of the first connecting adhesive layer 31 and the second connecting adhesive layer 32 needs to be strictly controlled. In this embodiment, the thickness of the first connecting adhesive layer 31 and the second connecting adhesive layer 32 are both H1, and the distance between the upper glass substrate 11 and the lower glass substrate 12 is H2, H1:H2＜1/7. Normally, the thickness between the upper glass substrate 11 and the lower glass substrate 12 is about 0.7mm, that is, the thickness of the first connecting adhesive layer 31 and the second connecting adhesive layer 32 is H1＜0.1mm. By controlling the thickness H1 of the first connecting adhesive layer 31 and the second connecting adhesive layer 32 to be less than 0.1 mm, the thickness of the first connecting adhesive layer 31 and the second connecting adhesive layer 32 is ensured to be relatively small. Therefore, the first connecting adhesive layer 31 and the second connecting adhesive layer 32 themselves will not affect the overall waterproof effect, but only provide a "bridge" between the glass substrate and the butyl adhesive layer to improve the long-term reliability of the connection between the butyl adhesive layer and the glass substrate.

Depending on the specific material, the optimal thickness range is slightly different. The following is a specific description of the thickness of the connecting adhesive layer of different materials in combination with different embodiments:

In the first embodiment, the sealing adhesive layer 20 is a butyl adhesive layer, the first connecting adhesive layer 31 and the second connecting adhesive layer 32 are both POE adhesive film layers, and the thickness is H1. The thickness of the POE adhesive film H1 is less than 0.05 mm. The waterproof performance of the POE adhesive film is second only to that of butyl adhesive, which can effectively reduce the passage of water vapor into the interior of the photovoltaic module, thereby improving the waterproof effect. The following is a specific description of the thickness of the connecting adhesive layer of this embodiment in combination with the experimental data in Table 1:

Table 1

According to the first row of data in Table 1, when H1 is 0, it means that there is no connecting adhesive layer, that is, the sealing adhesive layer 20 is directly connected to the glass substrate in the prior art; when H1 is 0.01 or above, it means that the sealing adhesive layer 20 is bonded to the glass substrate through the POE adhesive film layer.

According to the second row of data in Table 1, it can be seen that when H1 is 0.01 or above, the connection strength is significantly higher than the case where the sealant layer 20 is directly bonded to the glass substrate. This is because the POE film layer has good adhesion to the glass substrate and the sealant layer 20, and the sealant layer 20 is bonded to the glass substrate through the POE film layer, and the bonding strength is higher.

It should be noted that the third row of data in Table 1 represents the time taken for external water vapor to penetrate into the interior of the photovoltaic module under the conditions of a temperature of 85°C and a humidity of 85% (hereinafter referred to as the water penetration time). It can be seen that when H1 is 0, that is, when the sealant layer 20 is directly bonded to the glass substrate, the water penetration time is 1000 h (hours); when H1 is 0.01 mm, the water penetration time is 3000 h (hours); when H1 is 0.03 mm, the water penetration time is 2800 h (hours); when H1 is 0.05 mm, the water penetration time is 2600 h (hours); when H1 is 0.1 mm and above, the water penetration time is 2000 h (hours).

It can be seen that when the butyl rubber layer is directly bonded to the glass substrate, the water penetration time is shorter. This is because the bonding duration between the butyl rubber layer and the glass substrate is shorter. Therefore, over time, the butyl rubber layer and the glass substrate are more likely to separate, resulting in a gap to form a water inlet channel, allowing water vapor to enter the interior of the photovoltaic module.

After the POE adhesive film layer is used, the water penetration time is longer, because the POE adhesive film layer and the upper glass substrate 11 and the lower glass substrate 12 not only have stronger bonding strength, but also have longer bonding duration. As time goes by, the POE adhesive film layer and the upper glass substrate 11 and the lower glass substrate 12 are not easy to separate, which can ensure the reliability of the bonding. Therefore, compared with the prior art, the connection is more reliable when the POE adhesive film layer is used, and it is less likely to produce gaps between the butyl adhesive layer and the glass substrate. Therefore, it is less likely to produce water inlet channels, the water penetration time is longer, and the sealing performance of the photovoltaic module is also stronger.

In addition, it can be seen that as the thickness of the POE film layer increases, the water penetration time becomes shorter, that is, the time it takes for external water vapor to enter the photovoltaic module becomes shorter. This is because the sealing effect of the POE film layer is poorer than that of the butyl layer and it will still penetrate water. As the thickness of the POE film layer increases, it is easier to penetrate water. When the thickness of the POE film layer exceeds 0.05mm, the thicker POE film layer itself will become a water penetration channel, resulting in a faster increase in the water penetration speed and a significant shortening of the water penetration time, reaching an unusable state. Therefore, the thickness of the POE film layer needs to be controlled to be less than 0.05mm to ensure the sealing performance.

According to the second embodiment of the present invention, a photovoltaic module is also disclosed, and its structure is basically the same as that of the first embodiment, except that in this embodiment, the first connecting adhesive layer 31 and the second connecting adhesive layer 32 are both silicone adhesive layers, and the thickness H1 of the silicone adhesive layer is less than 0.04 mm. The thickness of the connecting adhesive layer of this embodiment is specifically described below in combination with the experimental data in Table 2:

Table 2

According to the first row of data in Table 2, when H1 is 0, it means that there is no connecting adhesive layer, that is, the sealing adhesive layer 20 is directly connected to the glass substrate in the prior art; when H1 is 0.01 or above, it means that the sealing adhesive layer 20 is bonded to the glass substrate through the silicone adhesive layer.

According to the second row of data in Table 2, it can be seen that when H1 is 0.01 or above, the connection strength is significantly higher than the case where the sealant layer 20 is directly bonded to the glass substrate. This is because the silicone adhesive layer has good adhesion to the glass substrate and the sealant layer 20, and the sealant layer 20 is bonded to the glass substrate through the silicone adhesive layer, and the bonding strength is higher.

It should be noted that the third row of data in Table 2 represents the time taken for external water vapor to penetrate into the interior of the photovoltaic module under the conditions of a temperature of 85°C and a humidity of 85% (hereinafter referred to as the water penetration time). It can be seen that when H1 is 0, that is, when the sealant layer 20 is directly bonded to the glass substrate, the water penetration time is 1000 h (hours); when H1 is 0.01 mm, the water penetration time is 2000 h (hours); when H1 is 0.02 mm, the water penetration time is 1800 h (hours); when H1 is 0.04 mm, the water penetration time is 1600 h (hours); when H1 is 0.1 mm and above, the water penetration time is 800 h (hours).

It can be seen that when the butyl rubber layer is directly bonded to the glass substrate, the water penetration time is shorter. This is because the bonding duration between the butyl rubber layer and the glass substrate is shorter. Therefore, over time, the butyl rubber layer and the glass substrate are more likely to separate, resulting in a gap to form a water inlet channel, allowing water vapor to enter the interior of the photovoltaic module.

After the silicone adhesive layer is used, the water penetration time is longer, because the silicone adhesive layer and the upper glass substrate 11 and the lower glass substrate 12 not only have a stronger bonding strength, but also have a longer bonding duration. As time goes by, the silicone adhesive layer and the upper glass substrate 11 and the lower glass substrate 12 are not easy to separate, which can ensure the reliability of the bonding. Therefore, compared with the prior art, the connection using the silicone adhesive layer is more reliable, and it is less likely to have a gap between the butyl adhesive layer and the glass substrate. Therefore, it is less likely to have a water inlet channel, the water penetration time is longer, and the sealing performance of the photovoltaic module is also stronger.

In addition, it can be seen that as the thickness of the silicone layer increases, the time it takes for water to enter the photovoltaic module becomes shorter. This is because the sealing effect of the silicone layer is relatively poor compared to the sealant layer 20 and it will still be permeable. As the thickness of the silicone layer increases, it is easier for water to permeate. When the thickness of the silicone layer is greater than 0.04mm, the thicker silicone layer itself will become a water permeation channel, and its water permeation rate will increase rapidly, resulting in a significant shortening of the water permeation time to an unusable state. Therefore, the thickness of the silicone layer needs to be controlled to be less than 0.04mm to ensure the sealing performance.

According to the third embodiment of the present invention, a photovoltaic module is also disclosed, and its structure is basically the same as that of the first embodiment, except that, in this embodiment, the first connecting adhesive layer 31 and the second connecting adhesive layer 32 are both EVA adhesive film layers, and the thickness H1 of the EVA adhesive film layer is less than 0.05 mm. The thickness of the connecting adhesive layer of this embodiment is specifically described below in combination with the experimental data in Table 3:

table 3

According to the first row of data in Table 3, when H1 is 0, it means that there is no connecting adhesive layer, that is, the sealing adhesive layer 20 is directly connected to the glass substrate in the prior art; when H1 is 0.01 or above, it means that the sealing adhesive layer 20 is bonded to the glass substrate through the EVA adhesive film layer.

It can be seen that when H1 is 0.01 or above, the connection strength is significantly higher than the case where the sealant layer 20 is directly bonded to the glass substrate. This is because the EVA film layer has good adhesion to the glass substrate and the sealant layer 20. The sealant layer 20 is bonded to the glass substrate through the EVA film layer, and the bonding strength is higher and the reliability is also higher.

It should be noted that the third row of data in Table 3 represents the time taken for external water vapor to penetrate into the interior of the photovoltaic module under the conditions of a temperature of 85°C and a humidity of 85% (hereinafter referred to as the water penetration time). It can be seen that when H1 is 0, that is, when the sealant layer 20 is directly connected to the glass substrate, the water penetration time is 1000 h (hours); when H1 is 0.01 mm, the water penetration time is 2500 h (hours); when H1 is 0.03 mm, the water penetration time is 2300 h (hours); when H1 is 0.05 mm, the water penetration time is 2000 h (hours); when H1 is 0.1 mm, the water penetration time is 1200 h (hours); and when H1 is 0.11 mm, the water penetration time is 800 h (hours).

It can be seen that when the butyl rubber layer is directly bonded to the glass substrate, the water penetration time is shorter. This is because the bonding duration between the butyl rubber layer and the glass substrate is shorter. Therefore, over time, the butyl rubber layer and the glass substrate are more likely to separate, resulting in a gap to form a water inlet channel, allowing water vapor to enter the interior of the photovoltaic module.

After the EVA film layer is used, the water penetration time is longer, because the bonding strength between the EVA film layer and the upper glass substrate 11 and the lower glass substrate 12 is not only greater, but also the bonding duration is longer. As time goes by, the EVA film layer is not easy to separate from the upper glass substrate 11 and the lower glass substrate 12, which can ensure the reliability of the bonding. Therefore, compared with the prior art, the connection is more reliable when the EVA film layer is used, and it is less likely to have a gap between the butyl layer and the glass substrate. Therefore, it is less likely to have a water inlet channel, the water penetration time is longer, and the sealing performance of the photovoltaic module is also stronger.

In addition, it can be seen that as the thickness of the EVA film layer increases, the time it takes for the photovoltaic module to enter water becomes shorter. This is because the sealing effect of the EVA film layer is relatively poor compared to the sealant layer 20, and it will still penetrate water. As the thickness of the EVA film layer increases, it is easier for water to penetrate. When the thickness of the EVA film layer is greater than 0.05mm, the thicker EVA film layer itself will become a water permeation channel, resulting in a significant shortening of the water permeation time and reaching an unusable state. Therefore, the thickness of the EVA film layer needs to be controlled to be less than 0.05mm to ensure the sealing performance.

According to the fourth embodiment of the present invention, a photovoltaic module is also disclosed, and its structure is basically the same as that of the first embodiment, except that, in the present embodiment, the first connecting adhesive layer 31 and the second connecting adhesive layer 32 are both PVB adhesive film layers, and the thickness H1 of the PVB adhesive film layer is less than 0.05 mm. The thickness of the connecting adhesive layer of the present embodiment is specifically described below in combination with the experimental data in Table 4:

Table 4

According to the first row of data in Table 4, when H1 is 0, it means that there is no connecting adhesive layer, that is, the sealing adhesive layer 20 is directly connected to the glass substrate in the prior art; when H1 is 0.01 or above, it means that the sealing adhesive layer 20 is bonded to the glass substrate through the PVB adhesive film layer.

It can be seen that when H1 is 0.01 or above, the connection strength is significantly higher than the case where the sealant layer 20 is directly bonded to the glass substrate. This is because the EVB film layer has good adhesion to the glass substrate and the sealant layer 20. The sealant layer 20 is bonded to the glass substrate through the PVB film layer, and the bonding strength is higher and the reliability is also higher.

It should be noted that the third row of data in Table 4 represents the time taken for external water vapor to penetrate into the interior of the photovoltaic module under the conditions of a temperature of 85°C and a humidity of 85% (hereinafter referred to as the water penetration time). It can be seen that when H1 is 0, that is, when the sealant layer 20 is directly bonded to the glass substrate, the water penetration time is 1000 h (hours); when H1 is 0.01 mm, the water penetration time is 2500 h (hours); when H1 is 0.03 mm, the water penetration time is 2200 h (hours); when H1 is 0.05 mm, the water penetration time is 1800 h (hours); when H1 is 0.1 mm, the water penetration time is 1000 h (hours); when H1 is 0.11 mm, the water penetration time is 800 h (hours).

It can be seen that when the butyl rubber layer is directly bonded to the glass substrate, the water penetration time is shorter. This is because the bonding duration between the butyl rubber layer and the glass substrate is shorter. Therefore, over time, the butyl rubber layer and the glass substrate are more likely to separate, resulting in a gap to form a water inlet channel, allowing water vapor to enter the interior of the photovoltaic module.

After the PVB film layer is used, the water penetration time is longer, because the PVB film layer and the upper glass substrate 11 and the lower glass substrate 12 not only have a stronger bonding strength, but also a longer bonding duration. As time goes by, the PVB film layer and the upper glass substrate 11 and the lower glass substrate 12 are not easy to separate, which can ensure the reliability of the bonding. Therefore, compared with the prior art, the connection is more reliable when the PVB film layer is used, and it is less likely to have a gap between the butyl adhesive layer and the glass substrate. Therefore, it is less likely to have a water inlet channel, the water penetration time is longer, and the sealing performance of the photovoltaic module is also stronger.

It can be seen that as the thickness of the PVB film layer increases, the time it takes for the photovoltaic module to be flooded becomes shorter. This is because the sealing effect of the PVB film layer is relatively poor compared to the sealant layer 20 and it will still leak water. As the thickness of the PVB film layer increases, it is easier for water to penetrate. When the thickness of the PVB film layer is greater than 0.05mm, the thicker EVA film itself will become a water permeation channel, resulting in a significant shortening of the water permeation time and reaching an unusable state. Therefore, the thickness of the PVB film layer needs to be controlled to be less than 0.05mm to ensure the sealing performance.

According to the fifth embodiment of the present invention, a photovoltaic module is also disclosed, and its structure is basically the same as that of the first embodiment, except that, in this embodiment, the first connecting adhesive layer 31 and the second connecting adhesive layer 32 are both EPE adhesive film layers, and the thickness H1 of the EPE adhesive film layer is less than 0.07 mm. The thickness of the connecting adhesive layer of this embodiment is specifically described below in combination with the experimental data in Table 5:

table 5

According to the first row of data in Table 5, when H1 is 0, it means that there is no connecting adhesive layer, that is, the sealing adhesive layer 20 is directly connected to the glass substrate in the prior art; when H1 is 0.01 or above, it means that the sealing adhesive layer 20 is bonded to the glass substrate through the EPE adhesive film layer.

It can be seen that when H1 is 0.01 or above, the connection strength is significantly higher than the case where the sealant layer 20 is directly bonded to the glass substrate. This is because the EPE film layer has good adhesion to the glass substrate and the sealant layer 20, indicating that the sealant layer 20 is bonded to the glass substrate through the EPE film layer, with higher bonding strength and higher reliability.

It should be noted that the third row of data in Table 5 represents the time taken for external water vapor to penetrate into the interior of the photovoltaic module under the conditions of a temperature of 85°C and a humidity of 85% (hereinafter referred to as the water penetration time). It can be seen that when H1 is 0, that is, when the sealant layer 20 is directly bonded to the glass substrate, the water penetration time is 1000 h (hours); when H1 is 0.03 mm, the water penetration time is 2500 h (hours); when H1 is 0.05 mm, the water penetration time is 2300 h (hours); when H1 is 0.07 mm, the water penetration time is 2000 h (hours); when H1 is 0.1 mm, the water penetration time is 1200 h (hours); when H1 is 0.11 mm, the water penetration time is 1200 h (hours).

It can be seen that when the butyl rubber layer is directly bonded to the glass substrate, the water penetration time is shorter. This is because the bonding duration between the butyl rubber layer and the glass substrate is shorter. Therefore, over time, the butyl rubber layer and the glass substrate are more likely to separate, resulting in a gap to form a water inlet channel, allowing water vapor to enter the interior of the photovoltaic module.

After the EPE film layer is used, the water penetration time is longer, because the EPE film layer and the upper glass substrate 11 and the lower glass substrate 12 not only have a stronger bonding strength, but also a longer bonding duration. As time goes by, the EPE film layer and the upper glass substrate 11 and the lower glass substrate 12 are not easy to separate, which can ensure the reliability of the bonding. Therefore, compared with the prior art, the connection is more reliable when the EPE film layer is used, and it is less likely to produce gaps between the butyl layer and the glass substrate. Therefore, it is less likely to produce water inlet channels, the water penetration time is longer, and the sealing performance of the photovoltaic module is also stronger.

It can be seen that as the thickness of the EPE film layer increases, the water penetration time becomes shorter. This is because the sealing effect of the EPE film layer is relatively poor compared to the sealant layer 20 and it will still penetrate water. As the thickness of the EPE film layer increases, it is easier to penetrate water. When the thickness of the EPE film layer is greater than 0.07 mm, the thicker EVA film layer itself will become a water penetration channel, and the water penetration rate will increase rapidly, resulting in a significant shortening of the water penetration time and reaching an unusable state. Therefore, the thickness of the EPE film needs to be controlled to be less than 0.07 mm to ensure the sealing performance.

It is to be understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of the present invention, but the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims (11)

1. A photovoltaic module, a packaging frame of the photovoltaic module comprising:

Sequentially laminating an upper glass substrate (11), a first connecting adhesive layer (31), a sealing adhesive layer (20), a second connecting adhesive layer (32) and a lower glass substrate (12) which are hermetically bonded along the thickness direction of the photovoltaic module; it is characterized in that the method comprises the steps of,

The bonding strength between the first connection adhesive layer (31)/the second connection adhesive layer (32) and the inner surface of the upper glass substrate (11)/the lower glass substrate (12) is greater than the bonding strength between the sealing adhesive layer (20) and the inner surface of the upper glass substrate (11)/the lower glass substrate (12).

2. The photovoltaic module of claim 1, wherein the photovoltaic module comprises,

The aging resistance of the first connection glue layer (31)/the second connection glue layer (32) is stronger than that of the sealing glue layer (20).

3. The photovoltaic module of claim 2, wherein the photovoltaic module comprises,

The sealant layer (20) is a butyl adhesive layer;

The first connection adhesive layer (31)/the second connection adhesive layer (32) is any one of a silicone adhesive layer, a polyurethane adhesive layer, a POE adhesive layer, an EVA adhesive layer, a PVB adhesive layer or an EPE adhesive layer.

4. The photovoltaic module according to claim 3,

The first connection adhesive layer (31)/the second connection adhesive layer (32) are the same width as the sealing adhesive layer (20), and the width range is 8-12mm.

5. The photovoltaic module according to claim 3,

The thickness of the first connection adhesive layer (31)/the second connection adhesive layer (32) is H1, and the distance between the upper glass substrate (11) and the lower glass substrate (12) is H2, wherein H1 is less than 1/7.

6. The photovoltaic module of claim 5, wherein the photovoltaic module comprises,

The first connection adhesive layer (31)/the second connection adhesive layer (32) are POE adhesive layers, and H1 is smaller than 0.05mm.

7. The photovoltaic module of claim 5, wherein the photovoltaic module comprises,

The first connection adhesive layer (31)/the second connection adhesive layer (32) are silicone adhesive layers, and H1 is smaller than 0.04mm.

8. The photovoltaic module of claim 5, wherein the photovoltaic module comprises,

The first connection adhesive layer (31)/the second connection adhesive layer (32) are EVA adhesive layers, and H1 is smaller than 0.05mm.

9. The photovoltaic module of claim 5, wherein the photovoltaic module comprises,

The first connection adhesive layer (31)/the second connection adhesive layer (32) are PVB adhesive layers, and H1 is smaller than 0.05mm.

10. The photovoltaic module of claim 5, wherein the photovoltaic module comprises,

The first connection adhesive layer (31)/the second connection adhesive layer (32) are EPE adhesive layers, and H1 is smaller than 0.07mm.

11. The photovoltaic module of claim 3, further comprising:

The battery piece layer (40) is arranged between the upper glass substrate (11) and the lower glass substrate (12), the sealant layer (20), the first connecting adhesive layer (31) and the second connecting adhesive layer (32) are all arranged around the periphery of the battery piece layer (40), the upper glass substrate (11) and the lower glass substrate (12) are arranged on the periphery of the battery piece layer (40), and the first connecting adhesive layer (31), the second connecting adhesive layer (32) and the sealant layer (20) are enclosed to form a sealing space for sealing the battery piece layer (40).