Heterojunction battery assembly without main grid

Abstract

The utility model relates to the related technical field of photovoltaic cell assemblies, and provides a main-grid-free heterojunction cell assembly, which comprises a cell panel, and the cell panel comprises front toughened glass and back toughened glass. A main-grid-free heterojunction cell string is arranged between the front tempered glass and the back tempered glass, and packaging adhesive films are arranged on the two sides of the main-grid-free heterojunction cell string; and butyl rubber is coated on the periphery between the front toughened glass and the back toughened glass for sealing. According to the utility model, the design of the packaging adhesive film, the utilization of the gaps between the battery pieces, the sealing of the periphery of the glass and the grid lines of the battery is optimized, the light conversion film EVA, the back glaze-plated toughened glass and the main-grid-free heterojunction battery string are adopted, and the periphery is sealed by butyl rubber, so that the power of the heterojunction battery assembly is improved, the cost is reduced, and the reliability of the product is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of photovoltaic cell modules, and specifically, to a main-grid-free heterojunction cell module. Background Art

[0002] The statements in this part only provide background technical information related to the utility model, and do not necessarily constitute prior art.

[0003] The heterojunction photovoltaic module increases the power output by improving the light absorption of the battery. In the existing method, a reflective film is arranged at the bottom of the battery pack to improve the absorption rate. Its working principle is as follows: sunlight enters the surface of the reflective film through the glass, total reflection occurs on the surface of the reflective film, the light is reflected to the lower surface of the photovoltaic glass, and then the light is reflected from the lower surface of the glass to the battery chip, so that the light loss is reduced and the power output can be increased.

[0004] The inventor found in the research that it is not easy to completely paste the reflective film with the bottom material of the battery pack, which is likely to cause defects such as uneven or insecure pasting, resulting in wrinkles and unevenness. Especially after the module is laminated, the reflective film is relatively thin and may present a convex surface, which will greatly affect the reflective effect of the reflective film material and the power output of the photovoltaic module. Moreover, when the heterojunction cell module is encapsulated with ordinary EVA (EVA is a copolymer of ethylene and vinyl acetate), the water resistance around the periphery is poor, and battery failure is more likely to occur around the periphery, resulting in product quality problems. Currently, the number of front grid lines of the heterojunction cells used is generally from 12 grid lines to 18 grid lines, resulting in a relatively low battery conversion efficiency, relatively thick grid lines, a large amount of low-temperature silver paste used, and a relatively high cost. Summary of the Utility Model

[0005] In order to solve the above problems, the utility model provides a main-grid-free heterojunction cell module, which optimizes the design of the encapsulation film, the utilization of the gap between the battery chips, the sealing around the glass, and the battery grid lines, improves the power of the heterojunction cell module, reduces the cost, and improves the reliability of the product.

[0006] In order to achieve the above purpose, the utility model adopts the following technical scheme:

[0007] One or more embodiments provide a main-grid-free heterojunction cell module, including a battery panel, and the battery panel includes a front tempered glass and a back tempered glass; a main-grid-free heterojunction battery string is arranged between the front tempered glass and the back tempered glass, and encapsulation films are arranged on both sides of the main-grid-free heterojunction battery string;

[0008] Butyl glue is coated and sealed around the periphery between the front tempered glass and the back tempered glass.

[0009] The utility model designs the battery grid lines of the battery string, and can realize a main-grid-free structure.

[0010] Further technical solution: on the back tempered glass, a white glaze layer is plated at the gap position corresponding to the cells of the main-gridless heterojunction cell string to reflect the light in the cell gaps to the cell surface.

[0011] The utility model adopts glazed tempered glass to realize the reflection of incident light on the cells, solves the defects such as wrinkles and unevenness that are likely to occur when using a reflective film, which are prone to uneven sticking or insecure sticking, improves the light reflection effect of the back tempered glass 5, and can improve the power output of the photovoltaic module.

[0012] Compared with the prior art, the beneficial effects of the utility model are as follows:

[0013] The utility model optimizes the design of the encapsulation adhesive film, the utilization of cell gaps, the glass peripheral seal and the cell grid lines. By adopting the light conversion film EVA, the back-glazed tempered glass, the main-gridless heterojunction cell string and butyl rubber seal around, the power of the heterojunction cell module is improved, the cost is reduced, and the reliability of the product is improved.

[0014] The advantages of the utility model and the advantages in additional aspects will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The attached drawings forming a part of this specification are used to provide a further understanding of the utility model. The schematic embodiments of the utility model and their descriptions are used to explain the utility model and do not constitute a limitation to the utility model.

[0016] Figure 1 It is a schematic structural diagram of a main-gridless heterojunction cell module in an embodiment of the utility model;

[0017] Figure 2 It is a schematic diagram of the cell structure of the main-gridless heterojunction cell string 3 in an embodiment of the utility model;

[0018] Figure 3 It is a schematic diagram of the back structure of a main-gridless heterojunction cell module in an embodiment of the utility model;

[0019] Wherein: 1, front tempered glass; 2, light conversion film EVA; 3, main-gridless heterojunction cell string; 4, anti-ultraviolet film EVA; 5, back tempered glass; 6, junction box; 7, aluminum frame; 8, silica gel; 9, grounding hole; 10, drainage hole; 11, mounting hole. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] The following further illustrates the utility model in conjunction with the drawings and embodiments.

[0021] It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present utility model. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present utility model belongs.

[0022] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present utility model. As used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0023] In the technical solutions disclosed in one or more embodiments, as Figures 1 to 3 shown, a main-gridless heterojunction battery module includes a battery panel, and the battery panel includes a front tempered glass 1 and a back tempered glass 5; a main-gridless heterojunction battery string 3 is disposed between the front tempered glass 1 and the back tempered glass 5, and encapsulation adhesive films are disposed on both sides of the main-gridless heterojunction battery string 3;

[0024] Butyl rubber is coated and sealed around between the front tempered glass 1 and the back tempered glass 5.

[0025] In traditional solar cells, the busbars are used to collect and conduct the photo-generated current, but they will block a part of the light and reduce the photoelectric conversion efficiency of the battery. In this embodiment, the battery grid lines of the battery string are designed to achieve a main-gridless structure. The main-gridless design uses other methods to adopt a back-contact or fine-grid line structure to collect the current, reduce the light blockage, and thus improve the efficiency.

[0026] Specifically, for the structure of the main-gridless heterojunction battery string 3, the front surface electrode structure of the battery string is improved. The front surface electrode of the main-gridless heterojunction battery string 3, as Figure 2 shown, includes a plurality of fine fingers, and the fine fingers are used to collect the photo-generated current. However, since they are very thin, the light-shielding loss is very small.

[0027] Preferably, the width of the fine fingers can reach the um level, the width of the fine fingers can be 50 um to 100 um, and preferably, the width of the fine fingers is 50 um, and the light-shielding loss is very small;

[0028] Specifically, the battery cells of the main-gridless heterojunction battery string 3 are main-gridless heterojunction half-cell double-sided batteries. The number of main grid lines on the front surface of the battery cells is 0. The sizes of the battery cells are as follows: 182 mm * 105 mm, 210 mm * 105 mm, 182 mm * 91 mm. The positive and negative poles between the battery cells are connected by low-temperature ultra-fine welding wires.

[0029] In this embodiment, by improving the layout design of the main grid lines, a main-grid-free setting of the grid lines of the cell is achieved.

[0030] Furthermore, the positive and negative electrodes of the main-grid-free heterojunction half-cell string 3 are connected in series by soldering with a low-temperature welding wire.

[0031] Optionally, the low-temperature welding wire can be a low-temperature aluminum welding wire, a low-temperature tin soldering wire, etc.;

[0032] In some embodiments, the encapsulation adhesive film provided between the front tempered glass 1 and the main-grid-free heterojunction half-cell string 3 can be a light-converting film EVA2;

[0033] Specifically, the light-converting film EVA2 is specifically EVA added with an ultraviolet absorber (UV agent) and a light-converting agent, which converts the solar spectrum into light more suitable for absorption by the photovoltaic cell.

[0034] The light-converting film EVA2 is used to convert the solar spectrum into light more suitable for absorption by the photovoltaic cell. The main function of the light-converting film EVA is to improve the power generation efficiency of the photovoltaic cell, reduce costs, and increase the power generation of the photovoltaic power station.

[0035] In some embodiments, the encapsulation adhesive film provided between the main-grid-free heterojunction cell string 3 and the back tempered glass 5 can be an anti-ultraviolet film EVA4;

[0036] Specifically, the anti-ultraviolet film EVA4 is specifically an EVA adhesive film added with an ultraviolet absorber (UV absorber), which increases the ultraviolet absorption ability.

[0037] For a further technical solution, a white glaze layer is plated on the gap position of the cells of the main-grid-free heterojunction cell string on the back tempered glass 5 to reflect the light in the cell gaps to the cell surface, improve the light utilization rate, and increase the power of the module.

[0038] In this embodiment, the glazed tempered glass is used to realize the reflection of the incident light of the cells, solve the defects such as uneven or insecure pasting and the appearance of wrinkles and unevenness existing in the existing use of the reflective film, improve the light reflection effect of the back tempered glass 5, and can improve the power output of the photovoltaic module.

[0039] For a further technical solution, a light-transmitting film is plated on the front surface of the front tempered glass 1 to improve the light transmittance;

[0040] Optionally, the light-transmitting film is specifically a silicon nitride coating with a thickness of about 120 nm, which increases the light transmittance.

[0041] In this embodiment, the front and back of each component in the assembly are distinguished by the incident light. The side facing the incident light is the front, and the side facing away from the incident light is the back.

[0042] In some embodiments, a junction box 6 is provided on the back of the battery panel. A three-piece junction box can be used. The junction box 6 is used to set photovoltaic elements and is electrically connected to external devices such as energy storage batteries connected to the photovoltaic module.

[0043] Specifically, the junction box 6 is adhered to the back of the back tempered glass 5 through silicone.

[0044] In some embodiments, an aluminum frame 7 is provided at the peripheral edge of the battery panel. The aluminum frame 7 is provided with a grounding hole 9, a drainage hole 10, and a mounting hole 11.

[0045] Optionally, the aluminum frame 7 is adhered to the battery panel through silicone 8 for encapsulating and protecting the battery panel.

[0046] During installation, the front tempered glass 1, light conversion film EVA 2, main-gridless heterojunction battery string 3, anti-ultraviolet EVA 4, and back enameled tempered glass 5 are sequentially arranged from top to bottom and arranged in a stacking order from bottom to top. On the back enameled tempered glass, a layer of white enamel is plated at the gap position corresponding to the battery cells of the main-gridless heterojunction battery string; the positive and negative electrodes of the main-gridless heterojunction battery string 3 are connected in series through low-temperature welding wires. Butyl glue is applied around between the front tempered glass 1 and the back enameled tempered glass 5 for sealing. Then, a certain amount of silicone 8 is injected onto the aluminum frame 7, and then the aluminum frame 7 is assembled onto the battery panel. Then, the junction box 6 is adhered to the back of the enameled back tempered glass 5 through silicone 8.

[0047] The photovoltaic module of this embodiment optimizes the design of the encapsulation film, the utilization of the battery cell gap, the sealing of the glass periphery, and the battery grid lines. By using the light conversion film EVA 2, the back enameled tempered glass 5, 20 - 26 main-gridless heterojunction battery strings, and butyl glue for sealing around, the power of the heterojunction battery module is improved, the cost is reduced, and the reliability of the product is enhanced.

[0048] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, various changes and modifications can be made to the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

[0049] Although the specific implementation manners of the present utility model have been described above in conjunction with the attached drawings, it is not a limitation on the protection scope of the present utility model. Those skilled in the art should understand that, based on the technical solutions of the present utility model, various modifications or deformations that can be made by those skilled in the art without creative efforts are still within the protection scope of the present utility model.

Claims

1. A main-gridless heterojunction battery component, characterized in that: It includes a battery panel, and the battery panel includes a front tempered glass and a back tempered glass; between the front tempered glass and the back tempered glass, a main-gridless heterojunction battery string is provided, and encapsulation glue films are provided on both sides of the main-gridless heterojunction battery string; Butyl glue is coated and sealed around between the front tempered glass and the back tempered glass; The front surface electrode of the main-gridless heterojunction battery string includes multiple fine grid lines, and the fine grid lines are used to collect photo-generated current, and the width of the fine grid lines is 50um to 100um; On the back tempered glass, a white glaze layer is plated at the gap position of the battery cells corresponding to the main-gridless heterojunction battery string to reflect the light in the battery cell gap to the surface of the battery cells.

2. The heterojunction battery component without main grid according to claim 1, characterized in that: The battery cells of the main-gridless heterojunction battery string are main-gridless heterojunction half-cell double-sided batteries.

3. The passivated emitter and rear contact (PERC) solar cell module according to claim 2, wherein: The positive and negative electrodes of the main-gridless heterojunction half-cell battery string are connected in series by welding with low-temperature welding wires.

4. A main-gridless heterojunction battery component according to claim 1, characterized in that: The encapsulation glue film provided between the main-gridless heterojunction half-cell battery string and the back tempered glass is an anti-ultraviolet EVA film.

5. A main-gridless heterojunction battery component according to claim 1, characterized in that: The encapsulation glue film provided between the front tempered glass and the main-gridless heterojunction half-cell battery string is a light conversion EVA film.

6. The heterojunction battery component without main grid according to claim 1, characterized in that: A light-transmitting film is plated on the side of the front tempered glass facing the incident light.

7. A main-gridless heterojunction battery component according to claim 1, characterized in that: A junction box is provided on the back of the battery panel; the junction box is adhesively bonded to the back of the back tempered glass with silicone.

8. The heterojunction battery component without main grid according to claim 1, characterized in that: An aluminum frame is provided at the four peripheral edges of the battery panel, and grounding holes, drainage holes and mounting holes are provided on the aluminum frame.

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