CN209896071U

CN209896071U - Photovoltaic module with thermochromism coating layer

Info

Publication number: CN209896071U
Application number: CN201920723685.0U
Authority: CN
Inventors: 朱强忠; 刘松民; 朱琛; 吕俊
Original assignee: Taizhou Longi Solar Technology Co Ltd
Current assignee: Taizhou Longi Solar Technology Co Ltd
Priority date: 2019-05-20
Filing date: 2019-05-20
Publication date: 2020-01-03
Anticipated expiration: 2029-05-20

Abstract

The application discloses photovoltaic module with thermochromism coating film layer, include glass substrate, solar wafer and coat in thermochromism coating film layer on the glass substrate, thermochromism coating film layer on the glass substrate covers the current leakage region in the solar wafer. The technical scheme that this application provided can reduce the hot spot risk of subassembly by a wide margin under the prerequisite of guaranteeing the subassembly power, and not only the cost is lower, realizes moreover more easily.

Description

Photovoltaic module with thermochromism coating layer

Technical Field

The utility model relates to a solar energy component technical field, in particular to photovoltaic module with thermochromism coating film layer.

Background

In recent years, the hot spot risk of the photovoltaic module gradually rises, and the hot spots of partial modules are too high, so that a power station back panel is burnt, customer complaints are generated, and even a roof is burnt.

In order to reduce the risk of hot spots of the assembly, part of manufacturers adopt half-piece assemblies, the temperature of the hot spots of the assembly is expected to be reduced by 10-20 ℃, but for the whole assembly used in a large scale, the product design scheme adopted by the manufacturers is relatively less, and part of manufacturers enable the hot spots of the assembly to work in a low current region through intelligent assemblies so as to reduce the risk of the hot spots, but the intelligent junction box is relatively higher in price and still needs time to reduce cost and improve efficiency; part manufacturers design each battery plate parallel diode or sacrifice part of the area of the battery plate to prepare the parallel diode to reduce the risk of hot spots, and although the hot spot problem is solved, the assembly cost is greatly improved.

In view of this, it is an urgent problem to develop a photovoltaic module that can reduce the hot spot temperature and has a low cost.

SUMMERY OF THE UTILITY MODEL

In view of the above-mentioned defects or deficiencies in the prior art, it is an object of the present invention to provide a photovoltaic module with a thermochromic coating, which is less costly while reducing the risk of hot spots.

The utility model provides a photovoltaic module with thermochromism coating film layer, include:

a glass substrate, a solar cell and a thermochromism coating layer coated on the glass substrate,

the thermochromic coating layer on the glass substrate covers the leakage current area in the solar cell.

Furthermore, the leakage current region is a local leakage current point of the solar cell.

Furthermore, the leakage current region is a cutting edge of the solar cell.

Further, the coating area of the thermochromic coating layer covering the local leakage current point is a circle with a preset diameter or a square with a preset side length.

Further, the preset diameter or the preset side length is 1mm to 2 mm.

Furthermore, the local leakage current point covered by the thermochromism coating layer is a clamping point of the clamp.

Furthermore, each local leakage current point covered by the thermochromism coating layer is 1mm to 2mm away from the left edge or the right edge of the solar cell piece, and is 1/5 to 1/4 side length away from the upper edge or the lower edge of the solar cell piece.

Furthermore, the thermochromism coating layer covers the cutting edges of the solar cells, the inter-cell distance of the solar cells and the inter-cell distance of the solar cell string group.

Further, the coating area of the thermochromic coating layer is 0.5mm to 1.5mm larger than the cutting edge, the inter-chip distance, and the inter-string distance.

Further, the thermochromic coating layer is made of vanadium dioxide.

Has the advantages that: the application provides a photovoltaic module on thermochromism coating film layer, this thermochromism coating film layer covers the current leakage region in the solar wafer through covering different current leakage regions, can realize reducing the purpose of subassembly hot spot risk by a wide margin under the less prerequisite of subassembly power influence, not only the cost is lower, realizes simply moreover.

Drawings

Other features, objects and advantages of the present application will become more apparent upon reading of the following detailed description of non-limiting embodiments with reference to the attached drawings in which:

FIG. 1 is a schematic view of a thermochromic coating layer of the present invention applied with a local leakage current point;

FIG. 2 is a schematic view of a thermochromic coating layer coating the cut edge of a half cell provided by the present invention;

FIG. 3 is a schematic view of a thermochromic coated layer coated laminated battery cutting edge provided by the present invention;

FIG. 4 is a schematic view of a thermochromic coating layer coating the edges of the cells, the inter-cell spacing, and the inter-string spacing provided by the present invention;

reference numerals: 10 thermochromic grid coating layers, 11 photovoltaic glass, 12 coating areas of local leakage current points, 13 coating areas of the cutting edges of half batteries and 14 coating areas of the cutting edges of laminated batteries.

Detailed Description

The present application will be described in further detail with reference to the following drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the relevant invention and are not limiting of the invention. It should be noted that, for convenience of description, only the portions related to the present invention are shown in the drawings.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

At present, in order to reduce the risk of hot spots of the assembly, part of manufacturers adopt half-piece assemblies, the temperature of the hot spots of the assembly is expected to be reduced by 10-20 ℃, but for the whole assembly used in a large scale, the product design scheme adopted by the manufacturers is relatively less, and part of manufacturers enable the hot spots of the assembly to work in a low current region through intelligent assemblies so as to reduce the risk of the hot spots, but the price of the intelligent junction box is relatively higher, so that the cost is reduced and the efficiency is improved by needing time; part manufacturers design each battery plate parallel diode or sacrifice part of the area of the battery plate to prepare the parallel diode to reduce the risk of hot spots, and although the hot spot problem is solved, the assembly cost is greatly improved.

For solving the above-mentioned problem that exists among the prior art, the embodiment of the utility model provides a can reduce hot spot risk and lower photovoltaic module of cost in order to avoid the appearance of above-mentioned situation.

The application provides a photovoltaic module on thermochromism coating layer specifically includes:

and the thermochromic coating layer on the glass substrate covers the leakage current area in the solar cell.

In the embodiment, the thermochromic coating layer is used for coating a high-leakage-current-generation area in the solar cell, and the light transmittance of the coating area can be actively changed through the change of the surface temperature of the solar cell, wherein the light transmittance is reduced when the surface temperature of the hot spot is higher than the phase change temperature of the thermochromic film, so that the photoproduction current density of a current leakage point can be reduced, namely, the heat input of the hot spot in unit area is reduced, and the temperature of the hot spot of the component is reduced; compared with the prior art, the thermochromic coating layer only covers the leakage current point area, so that the influence on the power of the component is small; the method for greatly reducing the hot spot temperature provided by the embodiment is not only low in cost, but also relatively easy to implement.

Preferably, the glass substrate is made of soda lime glass substrate. According to the actual use requirement, the glass substrate is a transparent or colorful substrate which has a certain thickness and a certain area and can be coated with the thermochromism coating film on the surface, and generally, the area of the glass substrate is larger than that of the photovoltaic module.

Preferably, the thermochromic coating layer is made of vanadium dioxide, and can also be made of other phase change materials such as titanium oxide, niobium dioxide, nickel sulfide and the like. When the temperature of the thermochromic film rises above the phase change temperature of the thermochromic film, the thermochromic film is in a metal state and has a large number of free electrons, and the probability of collision between light and electrons when the light enters the thermochromic film is increased, so that the transmittance and the absorptivity are reduced, and the emissivity is increased. It should be noted that the material of the thermochromic coating layer in this embodiment is common knowledge.

Preferably, a thermochromic coating layer with the phase change temperature of 100 ℃ is adopted, or a thermochromic coating layer with the phase change temperature of 90-120 ℃ is adopted, and through tests, compared with the prior art, the hot spot temperature is greatly reduced by adopting the phase change temperature of 100 ℃.

Specifically, because thermochromism coating layer has the lower characteristic of light transmissivity, the highest transmissivity is only 80% before the phase transition, to photovoltaic module, if whole coating thermochromism coating layer, then subassembly power will descend by a wide margin, consequently the leakage current region of this embodiment coating solar wafer, especially the local high leakage current point that sends out, the coating area is very little like this, will be very little to the influence of subassembly power, just can reduce the hot spot risk through the coating of less area, this operation is realized more easily, and the cost is also lower.

The local leakage current point here may be, for example, a local leakage current point caused by insufficient local etching of the battery piece due to uneven diffusion of the dopant, a local leakage current point caused by insufficient etching due to a jig point, a local regular leakage current point, or a local leakage current point caused by other reasons.

Specifically, the size of the plating film that can cover the shape of the leakage current point is preset according to the shape of the actual leakage current point, for example, the size may be a circle with a preset diameter or a square with a preset side length.

Exemplary, as shown in fig. 1, it does the utility model provides a thermochromism coating layer coats a schematic diagram of local electric leakage current point, the local electric leakage current point that thermochromism coating layer covered in the figure is quartz boat anchor clamps exposed core, the anchor clamps exposed core has eight altogether, all be located the border position of solar wafer, total eight local electric leakage current points on every solar wafer promptly, the coating area 12 that has eight local electric leakage current points on the corresponding thermochromism coating layer, according to the shape characteristics of anchor clamps exposed core, the coating area of every exposed core can be the diameter and be 1mm to 2 mm's circle, also can be the length of side and be 1mm to 2 mm's square, the regional size of specific coating can be adjusted according to production technology precision. It should be noted that the central point of the plating area of each clamping point is located at the center of the clamping point of the fixture, so that the plating area at the position can better cover the leakage current point.

For example, the central point of each local current leakage point covered by the thermochromic coating layer is the clamping point of the fixture, and the position of the clamping point of the fixture changes with the difference of each clamping process of the fixture, specifically as shown in fig. 1, the central point of the coating area of each local current leakage point corresponds to the specific orientation distribution on the solar cell as follows:

the center of the local current leakage point is close to the left edge of the solar cell, the center point of the film coating area is 1mm to 2mm away from the right edge of the solar cell, the center of the local current leakage point is close to the upper edge, the center point of the film coating area is close to the side length of the upper edge 1/5 to 1/4 of the solar cell, and the center point of the film coating area is close to the lower edge of the solar cell, and the side length of the film coating area is close to the lower edge 1/5 to 1/4 of the solar cell.

Therefore, the local leakage current point on each solar cell is covered by the thermochromic coating layer, when hot spots occur, the transmittance of light at the position covered by the thermochromic film is reduced, the photo-generated current density at the position is reduced, and the temperature of the hot spot risk point is reduced.

If the local current leakage point on the solar cell is a current leakage point caused by other reasons, the specific position of the center point of the coating region on the cell should be determined according to the shape and size of the actual local current leakage point.

Furthermore, the leakage current region is a cutting edge of the solar cell.

Specifically, when the edge of the cell is not diffused unevenly and etched well, the cutting of the cell is damaged due to the cutting process of the cell, and the current leakage region is the cut edge of the solar cell, for example, for a half cell or a laminated cell, the cut edge of the cell generates a current leakage region due to the laser melting effect during cutting. The embodiment coats the cutting edge area of the solar cell, and has small influence on the power of the component compared with the whole coating area, so that the operation is easy to realize and the cost is lower.

When etching defects are caused by uneven diffusion of the impurity in the edge region of the solar cell, the leakage current region is concentrated in the edge region of the solar cell, and the edge region of the solar cell also needs to be covered during coating.

Specifically, for a sliced battery such as a half battery or a laminated battery, when the edge of the battery has no impurity diffusion unevenness, the thermochromic coating layer only needs to cover the cutting edge of the solar battery piece, and when the edge of the battery has impurity diffusion unevenness, the thermochromic coating layer needs to cover all the edges of the solar battery piece.

Specifically, for the edge of the cell at the inter-cell distance of the solar cell and the inter-cell distance of the solar cell string group, there is a leakage current point or a leakage current area, because there is no cell at the inter-cell distance and the inter-cell distance, the light energy transmitted by the cell is generally recycled through the back plate, the photoelectric conversion efficiency at this point is low, the thermo-chromic coating is coated at this inter-cell distance and inter-cell distance to reduce the transmittance of the light at this point, and further reduce the risk of hot spots at this point, and the influence on the power of the assembly is small.

In an example, as shown in fig. 2, it is a schematic diagram of the cutting edge of the half-cell coated with the thermochromic coating layer provided by the present invention, for the half-cell, the coating region 13 of the cutting edge of the half-cell in the diagram is located at the cutting edge of the cell, and the coating should cover the cutting edge of the cell, preferably, the covering region is 1mm larger than the peripheral direction of the cutting edge of the cell, and may also be a value within a range from 0.5mm to 1.5 mm.

For example, as shown in fig. 3, which is a schematic diagram of the cutting edge of the laminated battery coated with the thermochromic coating layer provided by the present invention, for the laminated battery, the coating region 14 of the cutting edge of the laminated battery is located at the cutting edge of the battery piece, and since only one side of the cutting region of the laminated battery is exposed to the light source, only the exposed cutting region is coated, and the coverage area thereof is preferably larger than the peripheral direction of the cutting edge of the battery piece by 1mm, and can also be a value within a range from 0.5mm to 1.5 mm.

It can be understood that such a manner of coating the cutting edge has little effect on the power of the assembly, can reduce the photo-generated current of the leakage current point, thereby reducing the risk of hot spots, and has simple operation and low cost.

Exemplary, as shown in fig. 4, it is the utility model provides a thermochromism coating layer coating battery piece edge, the schematic diagram of piece interval and cluster interval, obviously, this kind of coating is the mode of meshing coating, thermochromism net coating layer 10 is coated on photovoltaic glass 11 in the figure, photovoltaic glass 11's area is bigger than its below solar photovoltaic module's area, to photovoltaic module, when coating piece interval and cluster interval, the coverage area than piece interval and cluster interval peripheral direction preferred 1mm big can, also can be in the value of 0.5mm to 1.5mm within range, for example: when the sheet pitch is 2mm, the covered area is an area in which four sides of the area where the sheet pitch is located are each 1mm larger to the outer area, that is, an area in which the left, right, front, and rear sides of the sheet pitch are 1mm larger outward. The gridding coating mode can reduce the transmittance of the glass substrate at a leakage current point from 80% to below 40% when hot spots occur, thereby greatly reducing the photoproduction current and achieving the purpose of reducing the input electric power density per unit area to reduce the hot spot temperature of the leakage current point.

The P-type PERC single glass assembly will now be described. The spacing between the single-side assembly and the common battery piece is 1.5mm to 2mm, the distance between the battery strings is 2mm to 3mm, the vanadium dioxide thermochromism coating material is coated on the spacing between the single-side assembly and the distance between the single-side assembly and the common battery piece, the transmittance of the coating is 80%, the assembly power is slightly influenced due to the fact that the coating is only carried out in the gaps, the size of a coating area is 1mm larger than the left and right sides of the spacing between the single-side assembly and the distance between the single-side assembly and the battery strings in the front and back directions, the size of the coating area is larger than the outer area of the battery piece along the edges of the spacing between.

Now, the P-type single crystal double-sided double-glass assembly will be described again by way of example. When the double-sided double-glass assembly is used outdoors, back scattering light can be absorbed, and the photoproduction current of the photovoltaic assembly is increased, so that the power generation power is increased. When the power generation performance of the double-sided assembly is improved, the hot spot risk is correspondingly increased. The spacing between the common battery plates of the double-sided double-glass assembly is 1.5mm to 2mm, and the spacing between the strings is 2mm to 3 mm. For the transparent double-sided double-glass assembly, the light in the area can not be reused, so that the influence of the vanadium dioxide thermochromism coating material coated between the cell spacing and the string spacing on the power of the double-sided double-glass assembly is very small. In order to enable the thermochromic coating to better cover a leakage current point, the size of the coating area is 1mm larger than that of the area from the edge of the left and right front and back directions of the inter-chip distance and the inter-string distance to the outer area.

The above description is only a preferred embodiment of the application and is illustrative of the principles of the technology employed. It will be appreciated by those skilled in the art that the scope of the invention herein disclosed is not limited to the particular combination of features described above, but also encompasses other arrangements formed by any combination of the above features or their equivalents without departing from the spirit of the invention. For example, the above features may be interchanged with other features disclosed in this application, but not limited to those having similar functions.

Claims

1. A photovoltaic module with thermochromism coating layer is characterized by comprising:

2. The photovoltaic module with the thermochromic coating of claim 1 wherein the leakage current region is a local leakage current point of the solar cell.

3. The photovoltaic module with the thermochromic coating of claim 1 wherein the leakage current region is a cut edge of the solar cell.

4. The photovoltaic module with a thermochromic coating layer as claimed in claim 2, wherein the coating area of the thermochromic coating layer covering the local leakage current point is a circle with a predetermined diameter or a square with a predetermined side length.

5. The PV module with thermochromic coating of claim 4 wherein the predetermined diameter or the predetermined side length is 1mm to 2 mm.

6. The module according to claim 5, wherein the coating covers a localized creepage point which is a clamping point of the fixture.

7. The photovoltaic module with the thermochromic coating of claim 5, wherein each local creepage point covered by the thermochromic coating is 1mm to 2mm from the left or right edge of the solar cell sheet and is 1/5 to 1/4 side length from the upper or lower edge of the solar cell sheet.

8. The photovoltaic module with a thermochromic coating of claim 3, wherein the thermochromic coating covers the cut edges of the solar cells, the inter-cell spacing of the solar cells, and the inter-string spacing of the solar cell string.

9. The module of claim 8 wherein the coating area of the thermochromic coating is 0.5mm to 1.5mm larger than the cutting edge, the inter-chip distance and the inter-string distance.

10. The photovoltaic module with a thermochromic coating of claim 1 wherein the thermochromic coating is vanadium dioxide.