Battery assembly, battery string and photovoltaic system

Abstract

The embodiment of the utility model provides a battery assembly, a battery string and a photovoltaic system, and relates to the technical field of photovoltaic batteries. The battery assembly comprises a battery piece, a plurality of welding rods and a plurality of films. Wherein the plurality of welding strips are sequentially laid on one side of the battery piece at intervals in the preset direction, and the plurality of thin films are sequentially laid on one side, away from the battery piece, of the welding strips at intervals in the preset direction. On the basis, in order to ensure that each welding strip can be completely covered and accurately fixed at the corresponding position of the battery piece at the same time, the thin films correspond to the welding strips one by one, and the width of the thin films is larger than that of the welding strips. In the invention, the width size range of the film is 4-8 mm. Therefore, it is ensured that the welding strip is firmly and reliably fixed to the battery piece, and poor connection caused by position deviation is avoided; and the thin film is prevented from being too wide, so that the beneficial effects of reducing the use amount of the thin film, reducing the cost and effectively reducing the adverse influence of the accidental thin film quality on the assembly are achieved.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic cell technology, and more specifically, to a battery module, a battery string, and a photovoltaic system. Background Technology

[0002] Photovoltaic modules are an important direction for future energy development, especially OBB (Busbarless) technology. Traditional photovoltaic cell designs contain multiple busbars, while OBB technology reduces or even eliminates busbars, using finer solder ribbons to directly interconnect with the fine busbars to conduct current, thereby improving the photoelectric conversion efficiency of the cell and reducing costs.

[0003] However, the inventors discovered through research that the existing OBB coating solution involves covering the back of the battery cell with a carrier film, and then pressing the carrier film together with the battery cell and solder ribbon. This solution has the problems of large amount of carrier film used, high cost, and susceptibility to the quality of the adhesive film. Utility Model Content

[0004] The purpose of this invention is to provide a battery module, battery string, and photovoltaic system that can connect the solder ribbon and the battery cell through a thin film that corresponds one-to-one with the solder ribbon, thereby achieving the beneficial effects of reducing the amount of thin film used, reducing costs, and effectively reducing the adverse effects of occasional thin film quality on the module.

[0005] The embodiments of this utility model can be implemented as follows:

[0006] In a first aspect, this utility model provides a battery assembly, comprising:

[0007] Battery cells;

[0008] Multiple welding strips are laid sequentially and at intervals along a predetermined direction on one side of the battery cell;

[0009] Multiple thin films are laid sequentially and at intervals along a predetermined direction on the side of the welding ribbon away from the battery cell;

[0010] The film corresponds one-to-one with the solder strip, and the width of the film is greater than the width of the solder strip, with the width of the film ranging from 4 to 8 mm.

[0011] In an optional embodiment, multiple solder strips and multiple films are arranged at equal intervals along a preset direction.

[0012] In an optional embodiment, the spacing between two adjacent solder strips ranges from 7 to 11 mm.

[0013] In an optional implementation, the preset direction is the extension direction of the long side of the battery cell.

[0014] In an optional implementation, the length of any one of the solder strips is greater than the length of the short side of the solar cell.

[0015] In an optional embodiment, the transmittance of the film is greater than or equal to 91%.

[0016] In an optional implementation, the thin film, solder ribbon, and battery cell are joined using a lamination process.

[0017] In an optional embodiment, the film is one of POE, EVA, EPE, and PVB.

[0018] Secondly, the present invention provides a battery string comprising at least two battery components as described in any of the foregoing embodiments, wherein two adjacent battery components are connected in series by a solder strip.

[0019] Thirdly, this utility model provides a photovoltaic system, including a battery string as described in the foregoing embodiments.

[0020] The beneficial effects of the battery module, battery string, and photovoltaic system provided by this utility model embodiment include:

[0021] This utility model provides a battery module, a battery string, and a photovoltaic system. The battery module includes battery cells, multiple welding rods, and multiple thin films. The welding rods are sequentially and spaced apart along a predetermined direction on one side of the battery cells, and the thin films are sequentially and spaced apart along a predetermined direction on the side of the welding rods away from the battery cells. To ensure that each welding rod is completely covered and accurately fixed to its corresponding position on the battery cell, the thin film corresponds one-to-one with the welding rod, and the width of the thin film is greater than the width of the welding rod. In this application, the width of the thin film ranges from 4 to 8 mm. This ensures, on the one hand, that the welding rods are firmly and reliably fixed to the battery cells, avoiding poor connection due to positional misalignment; on the other hand, it avoids excessively large thin film sizes, thereby reducing the amount of thin film used, lowering costs, and effectively reducing the adverse effects of occasional thin film quality issues on the module. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the battery assembly provided in this embodiment.

[0024] Icons: 10 - Battery assembly; 100 - Battery cell; 300 - Solder strip; 500 - Thin film. Detailed Implementation

[0025] In related technologies, battery modules employ a method of covering the back of the battery cells with a carrier film, and then pressing the carrier film together with the battery cells and solder ribbons. This method has the problems of large amount of carrier film used, high cost, and susceptibility to the quality of the adhesive film.

[0026] To address the aforementioned issues, this invention provides a battery module 10, a battery string, and a photovoltaic system, which can connect the solder ribbon 300 to the battery cell 100 through a thin film 500 that corresponds one-to-one with the solder ribbon 300. This achieves the beneficial effects of reducing the amount of thin film 500 used, lowering costs, and effectively reducing the adverse effects of occasional thin film 500 quality issues on the module.

[0027] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. The components of the embodiments of this utility model described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0028] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0029] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0030] In the description of this utility model, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the utility model product is usually placed during use, they are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0031] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0032] It should be noted that, where there is no conflict, the features in the embodiments of this utility model can be combined with each other.

[0033] The following describes in detail, through embodiments and in conjunction with the accompanying drawings, the overall structure, working principle, and technical effects of a battery module 10, battery string, and photovoltaic system provided by this utility model.

[0034] Please see Figure 1 This utility model provides a battery module 10, which is applied in the field of photovoltaic cell technology. The battery module 10 includes a battery cell 100, multiple welding rods, and multiple thin films 500. The multiple welding rods 300 are sequentially and spaced apart along a predetermined direction on one side of the battery cell 100, and the multiple thin films 500 are sequentially and spaced apart along a predetermined direction on the side of the welding rods 300 away from the battery cell 100.

[0035] Based on the above, in order to ensure that each solder ribbon 300 can be completely covered and accurately fixed at the corresponding position of the battery cell 100, the film 500 corresponds one-to-one with the solder ribbon 300, and the width of the film 500 is greater than the width of the solder ribbon 300.

[0036] In this application, the width of the thin film 500 ranges from 4 to 8 mm. Based on this, on the one hand, it ensures that the solder ribbon 300 is firmly and reliably fixed to the solar cell 100, avoiding poor connection due to positional misalignment; on the other hand, it avoids the thin film 500 being too large, thereby achieving the beneficial effects of reducing the amount of thin film 500 used, reducing costs, and effectively reducing the adverse effects of occasional thin film 500 quality on the module.

[0037] In particular, the aforementioned non-full-coverage coating method, compared to the traditional full-coverage coating method, saves more than 55.9% of the amount of film 500 used. This reduces the area of ​​film 500, saves costs, and lowers the risk of module degradation caused by film 500 quality issues. Furthermore, it should be noted that the film 500 completely covers each solder ribbon 300 laid on the solar cell 100 using a coating machine.

[0038] In some embodiments, to adapt to different application scenarios and production needs, the film 500 is one of POE (polyolefin elastomer), EVA (ethylene-vinyl acetate copolymer), EPE (crosslinked polyethylene), and PVB (polyvinyl butyral).

[0039] Among them, POE has the advantages of high transparency and excellent weather resistance, EVA has the advantages of good adhesion and low cost, EPE has the advantages of excellent mechanical properties and chemical resistance, and PVB has the advantages of high transparency and good impact strength. Therefore, production personnel can select according to actual needs, and no limitation is made in this application.

[0040] Furthermore, considering that the transmittance of the thin film 500 is one of the important factors affecting the photoelectric conversion efficiency of the battery module 10, in the embodiments provided in this application, the transmittance of the thin film 500 is greater than or equal to 91%. It is easy to understand that the thin film 500 based on the above-mentioned transmittance range can effectively reduce light loss, increase the amount of light received by the battery cell 100, and thus improve the photoelectric conversion efficiency of the battery cell 100.

[0041] To improve the electrical connection reliability of the battery module 10, the thin film 500, the solder ribbon 300, and the battery cell 100 are connected using a lamination process. It should be noted that the lamination process, on the one hand, uses high temperature and high pressure to tightly bond the thin film 500, solder ribbon 300, and battery cell 100 into a single unit, ensuring a strong and reliable electrical connection between the solder ribbon 300 and the battery cell 100. On the other hand, it can reduce the contact resistance between the solder ribbon 300 and the battery cell 100, improving current transmission efficiency and thus enhancing the overall performance of the battery module 10.

[0042] It should be noted that the lamination process is performed as follows:

[0043] The battery cells 100 are placed on the worktable of the laminator in a predetermined arrangement; the solder ribbons 300 are laid sequentially and at intervals along a predetermined direction on one side of the battery cells 100, ensuring that the contact position between the solder ribbons 300 and the battery cells 100 is accurate; the film 500 is laid sequentially and at intervals along a predetermined direction on the side of the solder ribbons 300 away from the battery cells 100, ensuring that the film 500 completely covers the solder ribbons 300 and that the edge of the film 500 extends beyond the width of the solder ribbons 300.

[0044] Next, the laminator is started, and a vacuum operation is performed to remove air from the components and ensure that the materials of each layer are tightly bonded. While vacuuming, the temperature is gradually increased to the melting temperature of the thin film 500. During heating, the thin film 500 melts and flows, filling the gaps between the cell 100 and the solder ribbon 300 to form a uniform adhesive layer. After reaching the set temperature, it is maintained for a period of time to ensure that the thin film 500 is completely melted and fully penetrated. Then, the temperature is gradually reduced to allow the thin film 500 to solidify, forming a robust laminated structure.

[0045] Please refer again. Figure 1 Multiple solder strips 300 are arranged at equal intervals along a preset direction. It is easy to understand that the equal intervals of the solder strips 300 can ensure that the current is evenly distributed among the cells 100, thereby reducing the hot spot effect caused by uneven local current density and improving the power generation efficiency and stability of the entire module.

[0046] Correspondingly, multiple thin films 500 are also equidistantly spaced along a preset direction to ensure that the protective layer thickness between each section of the solder strip 300 and the battery cell 100 is consistent, providing the beneficial effects of uniform environmental protection and mechanical support.

[0047] Furthermore, the spacing between two adjacent solder strips 300 ranges from 7 to 11 mm to further ensure uniform current distribution and improved light energy utilization. Optionally, the spacing between two adjacent solder strips 300 is 9 mm. It should also be noted that the above data are particularly applicable to solar cells 100 with a short side dimension of 182 mm, a long side dimension of 191.6 mm, a solder strip 300 diameter of 0.18 mm, and a grid line count of 20.

[0048] In the embodiments provided in this application, the preset direction is the extension direction of the long side of the solar cell 100. That is to say, multiple solder ribbons 300 and multiple thin films 500 are all spaced along the long side of the solar cell 100 to achieve the beneficial effects of reducing shading, reducing power loss, and improving module power and reliability. On this basis, in order to facilitate connection with adjacent solar modules 10, the length of any solder ribbon 300 is greater than the length of the short side of the solar cell 100.

[0049] In summary, this utility model embodiment provides a battery assembly 10, which includes a battery cell 100, multiple welding rods, and multiple thin films 500. The multiple welding rods 300 are sequentially and spaced apart along a predetermined direction on one side of the battery cell 100, and the multiple thin films 500 are sequentially and spaced apart along a predetermined direction on the side of the welding rods 300 away from the battery cell 100. Based on the above, to ensure that each welding rod 300 is completely covered and accurately fixed at its corresponding position on the battery cell 100, the thin films 500 correspond one-to-one with the welding rods 300, and the width of the thin film 500 is greater than the width of the welding rods 300. In this application, the width of the thin film 500 ranges from 4 to 8 mm. Based on this, on the one hand, it ensures that the solder ribbon 300 is firmly and reliably fixed to the battery cell 100 to avoid poor connection caused by positional misalignment; on the other hand, it avoids the film 500 being too large, thereby achieving the beneficial effects of reducing the amount of film 500 used, reducing costs, and effectively reducing the adverse effects of occasional film 500 quality on the module.

[0050] In addition, this application also provides a battery string comprising at least two battery modules 10 as described in the foregoing embodiments. Furthermore, adjacent battery modules 10 are connected in series via solder ribbons 300. Therefore, this battery string can also achieve the connection between the solder ribbons 300 and the battery cells 100 via thin films 500 corresponding one-to-one with the solder ribbons 300, thereby achieving the beneficial effects of reducing the amount of thin film 500 used, lowering costs, and effectively reducing the adverse effects of occasional thin film 500 quality issues on the module.

[0051] In addition, this application also provides a photovoltaic system including the battery string in the foregoing embodiments. Therefore, similarly, this photovoltaic system can also connect the solder ribbon 300 and the battery cell 100 through the thin film 500 corresponding one-to-one with the solder ribbon 300, thereby achieving the beneficial effects of reducing the amount of thin film 500 used, reducing costs, and effectively reducing the adverse effects of occasional thin film 500 quality on the module.

[0052] The above are merely specific embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model.

Claims

1. A battery assembly, characterized in that, include: Battery cells; Multiple welding strips are laid sequentially and at intervals along a predetermined direction on one side of the battery cell; Multiple thin films are sequentially and spaced apart along the preset direction on the side of the solder ribbon away from the battery cell; The film corresponds one-to-one with the solder strip, and the width of the film is greater than the width of the solder strip, with the width of the film ranging from 4 to 8 mm.

2. The battery assembly according to claim 1, characterized in that, The multiple solder strips and the multiple films are all equidistantly spaced along the preset direction.

3. The battery assembly according to claim 2, characterized in that, The spacing between two adjacent welding strips ranges from 7 to 11 mm.

4. The battery assembly according to any one of claims 1 to 3, characterized in that, The preset direction is the extension direction of the long side of the battery cell.

5. The battery assembly according to claim 4, characterized in that, The length of any one of the welding strips is greater than the length of the short side of the battery cell.

6. The battery assembly according to any one of claims 1 to 3, characterized in that, The transmittance of the film is greater than or equal to 91%.

7. The battery assembly according to any one of claims 1 to 3, characterized in that, The thin film, the solder ribbon, and the battery cell are connected by a lamination process.

8. The battery assembly according to any one of claims 1 to 3, characterized in that, The film is one of POE, EVA, EPE and PVB.

9. A battery string, characterized in that, It includes at least two battery modules as described in any one of claims 1 to 8, and two adjacent battery modules are connected in series via the solder strip.

10. A photovoltaic system, characterized in that, Includes the battery string as described in claim 9.

Images