Preparation method of photovoltaic module and photovoltaic module

Abstract

The invention relates to a preparation method of a photovoltaic module and the photovoltaic module, and the method comprises the steps: providing a back contact solar cell, printing insulation paste on the backlight surface of the back contact solar cell, carrying out light curing treatment on the insulation paste, carrying out heat curing treatment on the insulation paste, and enabling the time T1 of the light curing treatment to meet the condition that T1 is more than or equal to 1s and less than or equal to 3s, and enabling the time T2 of the heat curing treatment to meet the condition that T2 is more than or equal to 15s and less than or equal to 35s. The double curing process combining light curing and heat curing is adopted for the insulating glue on the backlight surface of the back contact solar cell, so that the curing time of the insulating glue can be shortened, the curing efficiency of the insulating glue can be improved, the production efficiency of a photovoltaic module can be improved, the bonding performance of the insulating glue can be improved, and the adhesive force between the insulating glue and the back contact solar cell can be enhanced; therefore, the stability and the reliability of the back contact solar cell are improved, the high temperature resistance of the insulation paste is improved, and the possibility of short circuit of the back contact solar cell caused by reduction and even failure of the insulation effect of the insulation paste under the influence of high temperature is reduced.

Description

Technical Field

[0001] The present application relates to the field of solar energy technology, and in particular to a method for preparing a photovoltaic module and a photovoltaic module. Background Art

[0002] Back contact solar cells can convert sunlight into electrical energy. The backlight side of the back contact solar cell is usually provided with insulating glue. Currently, the curing efficiency of the insulating glue is low and the performance of the insulating glue is poor, which affects the quality and production capacity of photovoltaic modules. Summary of the invention

[0003] In view of this, the present application provides a method for preparing a photovoltaic module and a photovoltaic module, so as to solve the problem of low curing efficiency of insulating glue in the prior art and improve the performance of the insulating glue.

[0004] In a first aspect, an embodiment of the present application provides a method for preparing a photovoltaic module, including providing a back-contact solar cell, printing an insulating glue on the backlight surface of the back-contact solar cell, photocuring the insulating glue, wherein the time T1 of the photocuring treatment satisfies: 1s≤T1≤3s, and thermally curing the insulating glue, wherein the time T2 of the thermal curing treatment satisfies: 15s≤T2≤35s.

[0005] In a possible implementation, the curing device includes a light curing mechanism, the light curing mechanism has at least three ultraviolet light sources arranged along a first direction, and the power P of a single ultraviolet light source satisfies: 1050mW / cm2≤P≤1500mW / cm2. The light curing treatment of the insulating adhesive includes: placing the back contact solar cell in the light curing mechanism, turning on each of the ultraviolet light sources, and moving the back contact solar cell along the first direction, so that each of the ultraviolet light sources performs light curing on the insulating adhesive.

[0006] In a possible implementation manner, the photocuring mechanism has three ultraviolet light sources arranged along the first direction, and the time t1 for a single ultraviolet light source to perform photocuring on the insulating adhesive satisfies: 0.5s≤t1≤1s.

[0007] In a possible implementation manner, the photocuring mechanism has four ultraviolet light sources arranged along the first direction, and the time t2 for a single ultraviolet light source to perform photocuring on the insulating adhesive satisfies: 0.4s≤t2≤0.75s.

[0008] In a possible implementation manner, when the insulating adhesive is subjected to a heat curing treatment, a temperature A of the heat curing treatment satisfies: 150°C≤A≤200°C.

[0009] In a possible embodiment, the curing equipment includes a heat curing mechanism, the heat curing mechanism includes a heat curing zone and a cooling zone, the heat curing treatment of the insulating adhesive includes placing the back contact solar cell in the heat curing zone for heat curing treatment, and after the insulating adhesive is heat cured, the method for preparing the photovoltaic module includes placing the back contact solar cell in the cooling zone for cooling treatment until the temperature of the back contact solar cell is less than or equal to 60°C.

[0010] In a possible implementation, the light curing mechanism and the heat curing mechanism are arranged along the first direction, the heat curing zone and the cooling zone are arranged along the first direction, and the curing device further comprises a transmission mechanism. The method for preparing the photovoltaic module comprises: allowing the transmission mechanism to drive the back contact solar cell to move along the first direction in the curing device.

[0011] In a possible implementation, after the insulating adhesive is heat-cured, the method for preparing the photovoltaic module includes: testing the back-contact solar cells; and serially welding the back-contact solar cells that have passed the test to form a cell string.

[0012] In a possible embodiment, the insulating adhesive includes at least a photoinitiator and a thermal initiator, the photoinitiator is at least one of photoinitiator 819, photoinitiator 907, photoinitiator 651, and photoinitiator 127, and the thermal initiator is at least one of dicarbonic acid peroxide, lauroyl peroxide, and ditoluoyl peroxide.

[0013] In a second aspect, a photovoltaic module is provided, wherein the photovoltaic module is prepared by the method for preparing a photovoltaic module in any of the above items, wherein the photovoltaic module comprises a cover plate, an encapsulation layer and at least one battery string, the encapsulation layer is located between the cover plate and the battery string, the cover plate is connected to the battery string through the encapsulation layer, and the battery string comprises a plurality of back-contact solar cells electrically connected to each other.

[0014] The embodiment of the present application provides a method for preparing a photovoltaic module and a photovoltaic module, including providing a back contact solar cell, printing an insulating glue on the backlight surface of the back contact solar cell, performing a light curing treatment on the insulating glue, the time T1 of the light curing treatment satisfies: 1s≤T1≤3s, and performing a heat curing treatment on the insulating glue, the time T2 of the heat curing treatment satisfies: 15s≤T2≤35s. The insulating glue on the backlight surface of the back contact solar cell adopts a dual curing process combining light curing and heat curing, which can shorten the curing time of the insulating glue and improve the curing efficiency of the insulating glue, thereby facilitating the improvement of the production efficiency of the photovoltaic module, and further facilitating the improvement of the production capacity of the photovoltaic module. The above-mentioned dual curing process can improve the bonding performance of the insulating glue, enhance the adhesion between the insulating glue and the back contact solar cell, so that the insulating glue can be better combined with the back contact cell, so as to improve the stability and reliability of the back contact solar cell, so as to ensure the performance of the photovoltaic module, at the same time, the high temperature resistance of the insulating glue is improved, thereby reducing the possibility of the insulating effect of the insulating glue decreasing or even failing under the influence of high temperature, causing the back contact solar cell to short-circuit, and also improving the stability and reliability of the back contact solar cell.

[0015] It should be understood that the foregoing general description and the following detailed description are exemplary only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0017] Figure 1 A flow chart of a method for preparing a photovoltaic module provided in one embodiment of the present application; Figure 2 A schematic diagram of a back-contact solar cell according to an embodiment of the present application; Figure 3 This is a schematic diagram of a curing device in one embodiment of the present application; Figure 4 A schematic diagram of a photovoltaic module provided in accordance with an embodiment of the present application.

[0018] Reference numerals: 1- back contact solar cell; 11- insulating glue; 12- positive electrode main grid; 13- negative electrode main grid; 14- positive electrode fine grid; 15- negative electrode fine grid; 100-curing device; 101-light curing mechanism; 1011-ultraviolet light source; 102-heat curing mechanism; 103-transmission mechanism; 200 - photovoltaic module; 201 - battery string; 202 - first cover plate; 203 - first packaging layer; 204 - second packaging layer; 205 - second cover plate. DETAILED DESCRIPTION

[0019] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0020] It should be clear that the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0021] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0022] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0023] like Figure 1 As shown, the embodiment of the present application provides a method for preparing a photovoltaic module, comprising: Step S1: Provide a back-contact solar cell. The back-contact solar cell has a light-receiving surface and a back-light surface along its thickness direction. The light-receiving surface is the surface that can be directly illuminated by sunlight, and the back-light surface is the surface that is not directly illuminated by sunlight. The back-contact solar cell sets all the grid lines (i.e., metal electrodes) on the back-light surface, so that the light-receiving surface is not blocked by the grid lines, reducing the shading area of ​​the light-receiving surface, eliminating the shading current loss of the grid lines, and realizing the maximum utilization of incident photons, thereby improving the photoelectric conversion efficiency of the back-contact solar cell.

[0024] After step S1, step S2 is entered: printing insulating glue on the backlight surface of the back contact solar cell. Since the positive and negative poles of the back contact solar cell are both arranged on the backlight surface, it is necessary to print insulating glue on the backlight surface to insulate the poles of different polarities to avoid short circuit of the back contact solar cell.

[0025] like Figure 2As shown, in some embodiments, the backlight surface of the back contact solar cell 1 may be provided with intersecting main grids and fine grids, the fine grids are used to collect and conduct the current generated by the back contact solar cell 1, and the main grids can collect the current on the fine grids for convergence, so as to facilitate the transmission of the current to the outside of the back contact solar cell. The main grids may include a positive main grid 12 and a negative main grid 13, and the fine grids may include a positive fine grid 14 and a negative fine grid 15, the positive main grid 12 is connected to the positive fine grid 14, and the negative main grid 13 is connected to the negative fine grid 15.

[0026] The above step S2 specifically includes: setting the insulating glue 11 between the positive electrode main grid 12 and the negative electrode fine grid 15 and between the negative electrode main grid 13 and the positive electrode fine grid 14. The insulating glue 11 can insulate and isolate the main grid from the fine grid with opposite polarity to avoid short circuit of the back contact solar cell 1, which is beneficial to improve the reliability of the photovoltaic module.

[0027] After step S2, step S3 is entered: the insulating adhesive is subjected to light curing treatment, and the time T1 of the light curing treatment satisfies: 1s≤T1≤3s. The insulating adhesive includes a photoinitiator, so that the insulating adhesive can be cured under light conditions. The above-mentioned light curing treatment time can be understood as the time for the light source to illuminate the insulating adhesive to cure it. The light curing treatment time T1 can be 1s, 1.1s, 1.2s, 1.3s, 1.4s, 1.5s, 1.6s, 1.7s, 1.8s, 1.9s, 2s, 2.1s, 2.2s, 2.3s, 2.4s, 2.5s, 2.6s, 2.7s, 2.8s, 2.9s or 3s, and of course it can also be other values ​​within the above range.

[0028] If the photocuring time is short, it will easily affect the photocuring effect and thus affect the performance of the insulating adhesive. If the photocuring time is long, the efficiency of the insulating adhesive curing process will decrease, affecting the production efficiency of the photovoltaic modules. Therefore, by limiting the photocuring time within the above range, the photocuring efficiency can be improved while ensuring the photocuring effect, thereby improving the production efficiency of the photovoltaic modules.

[0029] The insulating adhesive is photocured so that it can be quickly converted from a liquid state to a solid state. The insulating adhesive after photocuring has a high degree of curing and can hardly flow anymore. In other words, the insulating adhesive can be photocured to achieve a high degree of curing in a short time, which is beneficial to improve the curing efficiency of the insulating adhesive. The photocuring process can be carried out at room temperature and does not require the use of other materials such as chemical reagents, thereby simplifying the production process of photovoltaic modules.

[0030] After step S3, step S4 is entered: the insulating adhesive is subjected to heat curing treatment, and the time T2 of the heat curing treatment satisfies: 15s≤T2≤35s. The insulating adhesive may also include a thermal initiator so that the insulating adhesive can be cured under high temperature conditions. The time of the heat curing treatment may be understood as the time for the insulating adhesive to be cured under high temperature conditions. The time T2 of the heat curing treatment may be 15s, 16s, 17s, 18s, 19s, 20s, 21s, 22s, 23s, 24s, 25s, 26s, 27s, 28s, 29s, 30s, 31s, 32s, 33s, 34s ​​or 35s, and may of course be other values ​​within the above range.

[0031] If the heat curing treatment time is short, it will easily affect the heat curing effect, thereby affecting the performance of the insulating adhesive. If the heat curing treatment time is long, it will lead to a decrease in the efficiency of the insulating adhesive curing process, affecting the production efficiency of the photovoltaic module. Therefore, by limiting the heat curing treatment time within the above range, the heat curing efficiency can be improved while ensuring the heat curing effect, thereby improving the production efficiency of the photovoltaic module.

[0032] By performing a heat curing treatment after a light curing treatment on the insulating adhesive, the insulating adhesive can be completely cured. At the same time, the insulating adhesive has excellent comprehensive properties to improve the reliability of the insulating adhesive, thereby ensuring the performance of the back contact solar cell.

[0033] The embodiment of the present application adopts a dual curing process combining light curing and heat curing for the insulating glue on the backlight surface of the back-contact solar cell, which can shorten the curing time of the insulating glue and improve the curing efficiency of the insulating glue, thereby facilitating the improvement of the production efficiency of the photovoltaic module, and further facilitating the improvement of the production capacity of the photovoltaic module. The above-mentioned dual curing process can improve the bonding performance of the insulating glue, enhance the adhesion between the insulating glue and the back-contact solar cell, so that the insulating glue can be better combined with the back-contact solar cell, so as to improve the stability and reliability of the back-contact solar cell, so as to ensure the performance of the photovoltaic module. At the same time, the dual curing process can also make the insulating glue have excellent weather resistance. Specifically, the high temperature resistance of the insulating glue is improved, thereby reducing the possibility of the insulating effect of the insulating glue decreasing or even failing under the influence of high temperature, causing the back-contact solar cell to short-circuit, and also improving the stability and reliability of the back-contact solar cell.

[0034] In one possible embodiment, the insulating adhesive includes at least a photoinitiator and a thermal initiator. The photoinitiator is at least one of photoinitiator 819, photoinitiator 907, photoinitiator 651, and photoinitiator 127. The thermal initiator is at least one of dicarbonic acid peroxide, lauroyl peroxide, and ditoluoyl peroxide. The effects of the photoinitiator and the thermal initiator have been described above and will not be repeated here. By adopting the above-mentioned photoinitiator and thermal initiator, the insulating adhesive can be photocured and thermally cured, thereby improving the curing efficiency of the insulating adhesive, thereby improving the production efficiency of the photovoltaic module, and at the same time improving the comprehensiveness of the insulating adhesive, so that the insulating adhesive can play a stable and reliable insulating role on the back-contact solar cell, avoiding short circuits in the back-contact solar cell.

[0035] The insulating adhesive may further include an inorganic filler. Specifically, the inorganic filler may be colorless fumed silica. Fumed silica can improve the high temperature resistance of the insulating adhesive, thereby ensuring that the insulating adhesive has a reliable insulating effect.

[0036] In some embodiments, the insulating adhesive may also be colorless, which can improve the appearance of the photovoltaic module, thereby helping to expand the scope of use of the photovoltaic module to meet the needs of different usage scenarios.

[0037] like Figure 3 As shown, in a possible implementation, the curing device 100 includes a light curing mechanism 101, which can use ultraviolet light to cure the insulating adhesive. The light curing mechanism 101 has at least three ultraviolet light sources 1011 arranged along a first direction X, and the ultraviolet light source 1011 can be an ultraviolet lamp bead.

[0038] The light curing process for insulating adhesive includes: Step S31 : placing the back-contact solar cell in the light curing mechanism 101 .

[0039] After step 31 , the process proceeds to step S32 : turning on each ultraviolet light source 1011 , and moving the back contact solar cell sheet along the first direction X, so that each ultraviolet light source 1011 performs light curing on the insulating adhesive.

[0040] By providing multiple ultraviolet light sources 1011, the irradiation area of ​​ultraviolet light can be increased, and the efficiency of light curing can be improved, which is beneficial to improving the production capacity of photovoltaic modules. During the light curing process, the back contact solar cell can move along the direction in which the ultraviolet light sources 1011 are arranged, so that the back contact solar cell can be irradiated by multiple ultraviolet light sources 1011, thereby improving the effect of light curing.

[0041] The power P of a single ultraviolet light source 1011 satisfies: 1050 mW / cm 2≤P≤1500mW / cm 2 , for example, P can be 1050mW / cm 2 、1100mW / cm 2 、1150mW / cm 2 , 1200mW / cm 2 、1250mW / cm 2 、1300mW / cm 2 、1350mW / cm 2 、1400mW / cm 2 、1450mW / cm 2 or 1500mW / cm 2 , of course, it can also be other values ​​within the above range. The power of the three ultraviolet light sources 1011 can be consistent. If the power of a single ultraviolet light source 1011 is too low, it is necessary to extend the time of the photocuring treatment to ensure the effect of the photocuring, resulting in a decrease in the photocuring efficiency of the insulating glue, thereby affecting the production efficiency of the photovoltaic module. If the power of a single ultraviolet light source 1011 is too high, the energy consumption of the photocuring mechanism 101 is too large, resulting in an increase in the production cost of the photovoltaic module. By limiting the power of the ultraviolet light source 1011, the photocuring time can be shortened while ensuring the photocuring effect, so as to improve the curing efficiency of the insulating glue, which is beneficial to improving the production efficiency of photovoltaic modules and reducing the production cost of photovoltaic modules.

[0042] In a possible implementation, the photocuring mechanism has three ultraviolet light sources arranged along a first direction, and the time t1 for a single ultraviolet light source to perform photocuring on the insulating adhesive satisfies: 0.5s≤t1≤1s. For example, t1 can be 0.5s, 0.55s, 0.6s, 0.65s, 0.7s, 0.75s, 0.8s, 0.85s, 0.9s, 0.95s or 1s, and of course, it can also be a specific value within the above range. The time for the three ultraviolet light sources to perform photocuring on the insulating adhesive can be the same. By limiting the time for a single ultraviolet light source to perform photocuring on the insulating adhesive, the efficiency of photocuring can be improved while ensuring the photocuring effect, which is beneficial to improving the production efficiency of photovoltaic modules.

[0043] In some embodiments, the light curing mechanism has three ultraviolet light sources arranged along the first direction, and the power of each ultraviolet light source can be 1050 mW / cm 2 The time for each ultraviolet light source to perform light curing on the insulating adhesive can be 0.64s.

[0044] In some embodiments, the light curing mechanism has three ultraviolet light sources arranged along the first direction, and the power of each ultraviolet light source can be 1200mW / cm 2The time for each ultraviolet light source to perform light curing on the insulating adhesive can be 0.56s.

[0045] The time for the UV light source to perform photocuring on the insulating adhesive can be reduced by appropriately increasing the power of the UV light source, thereby further shortening the curing time of the insulating adhesive and improving the production efficiency of photovoltaic modules.

[0046] like Figure 3 As shown, in a possible implementation, the photocuring mechanism 101 has four ultraviolet light sources 1011 arranged along the first direction X, and the time t2 for a single ultraviolet light source 1011 to perform photocuring on the insulating glue satisfies: 0.4s≤t2≤0.75s. For example, t2 may be 0.4s, 0.42s, 0.46s, 0.48s, 0.5s, 0.52s, 0.55s, 0.6s, 0.65s, 0.7s, 0.72s or 0.75s, and of course, may be other values ​​within the above range. The time for the four ultraviolet light sources 1011 to perform photocuring on the insulating glue may be the same. By limiting the time for a single ultraviolet light source 1011 to perform photocuring on the insulating glue, the efficiency of photocuring can be improved while ensuring the photocuring effect, thereby facilitating improving the production efficiency of photovoltaic modules.

[0047] In some embodiments, the light curing mechanism has four ultraviolet light sources arranged along the first direction, and the power of each ultraviolet light source can be 1050 mW / cm 2 The time for each ultraviolet light source to perform light curing on the insulating adhesive can be 0.48s.

[0048] In some embodiments, the light curing mechanism has four ultraviolet light sources arranged along the first direction, and the power of each ultraviolet light source can be 1200mW / cm 2 The time for each ultraviolet light source to perform light curing on the insulating adhesive can be 0.42s.

[0049] The number and power of ultraviolet light sources and the time for each ultraviolet light source to perform photocuring treatment on the insulating adhesive can be adjusted according to the actual production needs of photovoltaic modules, so as to improve the production efficiency of photovoltaic modules and achieve the optimal production capacity of photovoltaic modules.

[0050] In a possible implementation, when the insulating adhesive is subjected to a heat curing treatment, the temperature A of the heat curing treatment satisfies: 150°C ≤ A ≤ 200°C. For example, the temperature A may be 150°C, 155°C, 160°C, 165°C, 170°C, 175°C, 180°C, 185°C, 190°C, 195°C or 200°C, and of course, may be other values ​​within the above range. By designing the temperature of the heat curing treatment to be between 150° and 200°C, the heat curing effect of the insulating adhesive can be ensured, and the performance of the insulating adhesive can be improved, so that it can play a reliable isolation role on the backlight surface of the back contact solar cell, and at the same time, the curing efficiency of the insulating adhesive can be ensured, so as to facilitate the production process of photovoltaic modules.

[0051] like Figure 3 As shown, in a possible implementation, the curing device 100 includes a heat curing mechanism 102, and the heat curing mechanism 102 includes a heat curing area (not shown in the figure) and a cooling area (not shown in the figure).

[0052] The heat curing treatment of the insulating adhesive includes: placing the back contact solar cell sheet in a heat curing zone for heat curing treatment. In some embodiments, the heat curing treatment of the insulating adhesive can be performed by a heat cycle blowing method.

[0053] After the insulating adhesive is thermally cured, the method for preparing the photovoltaic module includes: Step S5: Place the back-contact solar cell in a cooling zone for cooling treatment until the temperature of the back-contact solar cell is less than or equal to 60°C. The above-mentioned thermal curing treatment will increase the temperature of the back-contact solar cell. In order to ensure that the back-contact solar cell can smoothly enter the next production link, the back-contact solar cell can be cooled by air cooling and / or water cooling to facilitate the production process of photovoltaic modules. At the same time, cooling the insulating glue after thermal curing is beneficial to reduce the internal stress generated by the insulating glue during the thermal curing process and improve the bonding performance of the insulating glue, thereby improving the reliability of the insulating glue and enabling it to better combine with the back-contact solar cell.

[0054] like Figure 3 As shown, in a possible implementation, the method for preparing a photovoltaic module includes: enabling the transmission mechanism 103 to drive the back-contact solar cell to move along the first direction X in the curing device 100 .

[0055] Specifically, the curing device 100 may extend along a first direction X, and the first direction X may be regarded as the length direction of the curing device 100. As mentioned above, the curing device 100 includes a light curing mechanism 101 and a heat curing mechanism 102, and the light curing mechanism 101 and the heat curing mechanism 102 are arranged along the first direction X. The curing device 100 may also include a transmission mechanism 103, and the transmission mechanism 103 may have a conveyor belt, and the conveyor belt may drive the back contact solar cell to move along the first direction X, so that the back contact solar cell passes through the light curing mechanism 101 and the heat curing mechanism 102 in sequence, so as to facilitate light curing and heat curing of the insulating glue.

[0056] Inside the heat curing mechanism 102 , the heat curing area and the cooling area may be arranged along the first direction X, and the back contact solar cell may be transported in various areas inside the heat curing mechanism 102 driven by the transport mechanism 103 .

[0057] As mentioned above, in the photocuring mechanism 101, multiple ultraviolet light sources 1011 can be arranged along the first direction X, and the back-contact solar cell is moved in the photocuring mechanism 101 through the transmission mechanism 103, so that the back-contact solar cell can be irradiated by multiple ultraviolet light sources 1011, thereby improving the photocuring effect.

[0058] As can be seen from the above, by setting up the transmission mechanism 103, the back-contact solar cell can be moved inside the light-curing mechanism 101, inside the heat-curing mechanism 102, and between the light-curing mechanism 101 and the heat-curing mechanism 102, without the need to manually carry the back-contact solar cell, which is beneficial to improving the curing efficiency of the insulating glue, thereby improving the production efficiency of the photovoltaic module. In other words, part of the structure of the transmission mechanism 103 is located in the light-curing mechanism 101, part of the structure is located in the heat-curing mechanism 102, and another part of the structure is located between the light-curing mechanism 101 and the heat-curing mechanism 102. The moving speed of the transmission mechanism 103 can be set according to the actual production needs of the photovoltaic module to ensure the smooth transportation of the back-contact solar cell in the curing device 100.

[0059] In a possible implementation, after the insulating adhesive is thermally cured, the method for preparing a photovoltaic module includes: Step S6: Testing the back contact solar cell As mentioned above, after the insulating adhesive is heat cured, the entire back contact solar cell can be cooled to reduce its temperature to a preset range, and then the back contact solar cell can be tested.

[0060] In some embodiments, automatic optical inspection (AOI) can be used to inspect back-contact solar cells. AOI inspection can detect defects, foreign objects, fingerprints, etc. on back-contact solar cells to improve the quality of photovoltaic modules. At the same time, by using AOI inspection to replace manual visual inspection, the inspection efficiency and the accuracy of the inspection results can be improved.

[0061] Step S7: soldering the back-contact solar cells that have passed the test in series to form a battery string. Specifically, a plurality of back-contact solar cells can be arranged along a preset direction, wherein two adjacent back-contact solar cells can be mechanically and electrically connected via a welding strip, the welding strip can be connected to the main grid on the back-contact solar cell, and the number of welding strips can correspond to the number of main grids.

[0062] After step S6 and before step S7, gray glue can also be printed on a preset position on the backlight surface of the back-contact solar cell. The gray glue can serve as an electrical connection between the soldering ribbon and the main grid of the back-contact solar cell to improve the reliability of the photovoltaic module.

[0063] After obtaining the battery string, multiple battery strings can be connected in series or in parallel through a bus bar to form a battery module, and then a front packaging structure and a back packaging structure can be provided. The front packaging structure is arranged on the light-receiving surface of the battery module (i.e., the light-receiving surface of the back contact solar cell), and the back packaging structure is arranged on the backlight surface of the battery module (i.e., the backlight surface of the back contact solar cell), and then the front packaging structure, the battery module and the back packaging structure are laminated to form a laminate.

[0064] The above-mentioned front packaging structure includes a first cover plate and a first packaging layer. The first cover plate can be a glass cover plate with high light transmittance. The material of the first packaging layer can be one or more of ethylene-vinyl acetate copolymer (EVA), polyolefin elastomer (POE) and polyvinyl butyral (PVB). The above-mentioned back packaging structure includes a second cover plate and a second packaging layer. The material of the second cover plate can be glass, or the second cover plate can also be composited by multiple polymer film layers. The material of the second packaging layer can be one or more of the above-mentioned EVA, POE, and PVB. The front packaging structure and the back packaging structure can ensure that the battery assembly has good mechanical strength, reduce the impact of hail impact, wind blowing, mechanical vibration, etc., and can also improve the sealing of the battery assembly, improve its corrosion resistance and safety.

[0065] After obtaining the laminate, a frame connection and a junction box can be installed on the laminate to form a photovoltaic module. The frame is conducive to improving the mechanical strength of the photovoltaic module to ensure the reliability of the photovoltaic module. The junction box can realize the electrical connection between the photovoltaic module and the external device or the photovoltaic module.

[0066] like Figure 4 As shown, the embodiment of the present application provides a photovoltaic module 200, which is prepared by the preparation method of the photovoltaic module 200 in any of the above items. The photovoltaic module 200 includes a cover plate, an encapsulation layer and at least one battery string 201, the encapsulation layer is located between the cover plate and the battery string 201, the cover plate is connected to the battery string 201 through the encapsulation layer, and the battery string 201 includes a plurality of back-contact solar cells 1 electrically connected to each other.

[0067] The cover plate may include a first cover plate 202 and a second cover plate 205, the first cover plate 202 may be located at the upper layer of the photovoltaic module 200, and the second cover plate 205 may be located at the lower layer of the photovoltaic module 200. The encapsulation layer includes a first encapsulation layer 203 and a second encapsulation layer 204, the first encapsulation layer 203 may be located between the first cover plate 202 and the battery string 201, and the first encapsulation layer 203 is used to bond the first cover plate 202 and the battery string 201 together. The second encapsulation layer 204 may be located between the second cover plate 205 and the battery string 201, and the second encapsulation layer 204 is used to connect the battery string 201 and the second cover plate 205 together. The first cover plate 202, the first encapsulation layer 203, the battery string 201, the second encapsulation layer 204 and the second cover plate 205 may be arranged along the thickness direction of the photovoltaic module 200 and laminated together.

[0068] The materials of the first cover plate 202 , the second cover plate 205 , the first packaging layer 203 , and the second packaging layer 204 have been introduced above and will not be described again here.

[0069] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for preparing a photovoltaic module, characterized in that: include: Providing back contact solar cells; Printing insulating glue on the backlight surface of the back contact solar cell; The insulating adhesive is subjected to a light curing treatment, wherein the time T1 of the light curing treatment satisfies: 1s≤T1≤3s; The insulating adhesive is subjected to a heat curing treatment, and the time T2 of the heat curing treatment satisfies: 15s≤T2≤35s.

2. The method for preparing a photovoltaic module according to claim 1, characterized in that: The curing device comprises a light curing mechanism, wherein the light curing mechanism has at least three ultraviolet light sources arranged along a first direction, and the power P of a single ultraviolet light source satisfies: 1050mW / cm2≤P≤1500mW / cm2; The light-curing treatment of the insulating adhesive comprises: placing the back contact solar cell sheet in the light curing mechanism; Each of the ultraviolet light sources is turned on, and the back-contact solar cell sheet is moved along the first direction, so that each of the ultraviolet light sources performs photocuring on the insulating adhesive.

3. The method for preparing a photovoltaic module according to claim 2, characterized in that: The light curing mechanism has three ultraviolet light sources arranged along the first direction; The time t1 for a single ultraviolet light source to perform photocuring on the insulating adhesive satisfies: 0.5s≤t1≤1s.

4. The method for preparing a photovoltaic module according to claim 3, characterized in that: The light curing mechanism has four ultraviolet light sources arranged along the first direction; The time t2 for the single ultraviolet light source to perform photocuring on the insulating adhesive satisfies: 0.4s≤t2≤0.75s.

5. The method for preparing a photovoltaic module according to claim 1, characterized in that: When the insulating adhesive is subjected to a heat curing treatment, a temperature A of the heat curing treatment satisfies: 150°C≤A≤200°C.

6. The method for preparing a photovoltaic module according to claim 2, characterized in that: The curing device includes a heat curing mechanism, and the heat curing mechanism includes a heat curing zone and a cooling zone; The heat curing treatment of the insulating adhesive comprises: Placing the back contact solar cell sheet in the thermal curing zone for thermal curing treatment; After the insulating adhesive is subjected to thermal curing treatment, the method for preparing the photovoltaic module comprises: The back contact solar cell is placed in the cooling zone for cooling until the temperature of the back contact solar cell is less than or equal to 60°C.

7. The method for preparing a photovoltaic module according to claim 6, characterized in that: The light curing mechanism and the heat curing mechanism are arranged along the first direction, the heat curing area and the cooling area are arranged along the first direction, and the curing device further includes a transmission mechanism; The method for preparing the photovoltaic module comprises: The transmission mechanism drives the back-contact solar cell to move along the first direction in the curing device.

8. The method for preparing a photovoltaic module according to any one of claims 1 to 7, characterized in that: After the insulating adhesive is subjected to thermal curing treatment, the method for preparing the photovoltaic module includes: Testing the back contact solar cell; The back-contact solar cells that have passed the test are serially welded to form a cell string.

9. The method for preparing a photovoltaic module according to any one of claims 1 to 7, characterized in that: The insulating adhesive at least includes a photoinitiator and a thermal initiator; The photoinitiator is at least one of photoinitiator 819, photoinitiator 907, photoinitiator 651, and photoinitiator 127; The thermal initiator is at least one of dicarbonic acid peroxide, lauroyl peroxide and ditoluoyl peroxide.

10. A photovoltaic module, characterized in that: The photovoltaic module is prepared by the method for preparing a photovoltaic module according to any one of claims 1 to 9; The photovoltaic module includes a cover plate, an encapsulation layer and at least one battery string, the encapsulation layer is located between the cover plate and the battery string, the cover plate is connected to the battery string through the encapsulation layer, and the battery string includes a plurality of back-contact solar cells electrically connected to each other.

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