Photovoltaic module

Abstract

The application provides a photovoltaic module. The module comprises: a plurality of cell strings, each cell string comprising at least a first cell piece and a second cell piece, the first cell piece and the second cell piece having a front surface and a back surface, the front surface and / or the back surface being provided with a groove, the groove extending along a first direction, the first cell piece and the second cell piece comprising a plurality of fine grids, the fine grids being distributed on the front surface and the back surface at intervals, the fine grids extending along a second direction, the second direction being perpendicular to the first direction; and a plurality of welding strips, at least part of the welding strips being located in the groove, the welding strips connecting the front surface of the first cell piece and the back surface of the second cell piece. By optimizing the connection mode between the cell pieces, better welding performance of the module is obtained, the stress between the cell pieces and the welding strips is reduced, the stability and power generation efficiency of the module are improved, and the overall performance of the photovoltaic module is improved.

Description

Technical Field

[0001] This application relates to the field of photovoltaic manufacturing technology, and more specifically, to a photovoltaic module. Background Technology

[0002] As cell sizes gradually increase in the industry, module dimensions are becoming more standardized. Currently, the mainstream cell spacing for 182mm modules is 1.5mm, and for 210mm modules it is 0.8mm. However, due to slight deviations in cell placement during welding, the minimum cell spacing can reach 0.5mm. Smaller cell spacing results in a larger angle between the solder ribbon and the cell, leading to greater solder ribbon bending during lamination. This increases stress on the cell edges at interconnect points, potentially causing lamination breakage and ultimately module degradation.

[0003] Several existing technologies and products related to photovoltaic modules have their shortcomings. Photovoltaic modules are components that generate electricity using the photovoltaic effect. They are usually composed of solar cells, encapsulant film, glass, and cover plate. Solar cells are the main component of the module. The welding performance of solar cells at the module end directly affects the module's power generation performance and power. Because the current module cell spacing is small, generally less than 1.5mm, the minimum cell spacing may reach 0.5mm due to certain deviations in the cell placement position during welding. Summary of the Invention

[0004] This application provides a photovoltaic module to solve the problem in related technologies where the small spacing between solar cells leads to increased height of the solder ribbon bending, resulting in cell breakage during lamination.

[0005] According to one aspect of this application, a photovoltaic module is provided, comprising: a plurality of cell strings, each cell string including at least a first cell and a second cell, the first cell and the second cell having a front side and a back side, a groove being provided on the front side and / or the back side, the groove extending along a first direction, the first cell and the second cell including a plurality of fine grids spaced apart on the front side and the back side, the fine grids extending along a second direction perpendicular to the first direction; and a plurality of solder strips, at least a portion of the solder strips being located in the grooves, the solder strips connecting the front side of the first cell and the back side of the second cell.

[0006] Optionally, both the front and the back sides are provided with a plurality of spaced-apart grooves.

[0007] Optionally, the first and second solar cells further include multiple main grids, with at least some of the main grids located one-to-one in the groove, and the solder strip located on the side of the main grid away from the groove.

[0008] Optionally, the first battery cell and / or the second battery cell includes a plurality of sub-batteries, and the solder ribbon is also connected to the main grids of the plurality of sub-batteries in the first battery cell and / or the solder ribbon is also connected to the main grids of the plurality of sub-batteries in the second battery cell.

[0009] Optionally, the photovoltaic module further includes a buffer structure located between the groove wall and the solder strip.

[0010] Optionally, the buffer structure is located in the edge region of the first battery cell and the second battery cell, and the edge region is located at both ends of the groove in the length direction.

[0011] Optionally, the minimum distance between the edge region and the two ends of the groove is 1mm to 3mm.

[0012] Optionally, the maximum width of the buffer structure in the first direction is 0.3mm to 1.5mm, the maximum width in the second direction is 1mm to 5mm, and the thickness of the buffer structure is 0.05mm to 0.3mm.

[0013] Optionally, the buffer structure includes an adhesive material.

[0014] Optionally, the maximum depth of the groove is 5μm to 10μm, and the width of the groove is 0.20mm to 0.30mm.

[0015] This application provides a photovoltaic module comprising multiple cell strings and multiple solder ribbons. Each cell string includes at least a first cell and a second cell. Grooves are provided on the front and / or back sides of the first and second cells, with the grooves extending perpendicular to the extension direction of the grid lines of the cells. At least a portion of the solder ribbons is located within these grooves, connecting the front and back sides of the first and second cells. By providing grooves on the front and / or back sides of the cells and arranging the solder ribbons within them, the minimum thickness of the cells is reduced. This results in a smaller and smoother bending angle of the solder ribbons when connecting the front and back sides of multiple cells, thereby reducing stress between the cells and the solder ribbons and making the connection between them more stable and reliable. This solves the problem in related technologies where small spacing between cells leads to increased solder ribbon bending height and cell breakage during lamination. Attached Figure Description

[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0017] Figure 1This is a schematic diagram of battery interconnection according to an embodiment of this application;

[0018] Figure 2 This is a cross-sectional structural diagram of a photovoltaic module according to an embodiment of this application;

[0019] Figure 3 A partially enlarged schematic diagram of the interconnect side of a photovoltaic module provided in an embodiment of this application;

[0020] Figure 4 This is a three-dimensional structural schematic diagram of a photovoltaic module according to an embodiment of this application;

[0021] Figure 5 This is a cross-sectional structural diagram of another photovoltaic module provided according to an embodiment of this application.

[0022] The above figures include the following reference numerals:

[0023] 1. Battery string; 111. First battery cell; 112. Second battery cell; 2. Welding strip; 3. Groove; 4. Fine grid; 5. Buffer structure. Detailed Implementation

[0024] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0025] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0026] It should be noted that the terms "second," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be used interchangeably where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0027] In related technologies, as cell sizes gradually increase in the industry, module dimensions are becoming more standardized. Currently, the mainstream cell spacing for 182mm modules is 1.5mm, and for 210mm modules it is 0.8mm. During welding, due to slight deviations in cell placement, the minimum cell spacing can reach 0.5mm. The smaller the cell spacing, the larger the angle between the solder ribbon and the cell, resulting in a higher bending height of the solder ribbon during lamination. This increases the stress on the cell edges at the interconnection points, leading to lamination breakage and ultimately module degradation.

[0028] Several existing technologies and products have their shortcomings. Photovoltaic modules are components that generate electricity using the photovoltaic effect. They are usually composed of solar cells, encapsulant film, glass, and cover plate. Solar cells are an important part of the main module. The welding performance of solar cells at the module end directly affects the module's power generation performance and power. Because the current module cell spacing is small, generally less than 1.5mm, the minimum cell spacing may reach 0.5mm due to certain deviations in the cell placement position during welding.

[0029] Therefore, in order to address the above problems, this application provides a photovoltaic module, such as... Figures 1 to 2 As shown, it includes: multiple battery strings 1, each battery string 1 including at least a first battery cell 111 and a second battery cell 112, the first battery cell 111 and the second battery cell 112 having a front side and a back side, and a groove 3 provided on the front side and / or the back side, the groove 3 extending along a first direction, the first battery cell 111 and the second battery cell 112 including multiple fine grids 4, the fine grids 4 being spaced apart on the front side and the back side, the fine grids 4 extending along a second direction, the second direction being perpendicular to the first direction; multiple solder strips 2, at least a portion of the solder strips 2 being located in the grooves 3, the solder strips 2 connecting the front side of the first battery cell 111 and the back side of the second battery cell 112.

[0030] By creating grooves on the front and / or back of the aforementioned solar cells and arranging solder ribbons within these grooves, the minimum thickness of the solar cells is reduced. This allows for a smaller and smoother bending angle of the solder ribbons when connecting multiple solar cells on both the front and back sides, thereby reducing stress between the solar cells and the solder ribbons. This results in a more stable and reliable connection between the solar cells and the solder ribbons, leading to better module welding performance, improved module stability and power generation efficiency, and ultimately, enhanced overall photovoltaic module performance. This also solves the problem in related technologies where small spacing between solar cells leads to increased solder ribbon bending height, causing cell breakage during lamination.

[0031] In the above optional implementations, such as Figure 1 As shown, the photovoltaic module includes multiple cell strings 1 and multiple solder strips 2. Each cell string 1 includes a first cell 111 and a second cell 112; that is, each cell string 1 includes at least a first cell 111 and a second cell 112. Figure 2As shown, the solder ribbon 2 and the groove 3 are distributed along the first direction on the surface of the cell. The solder ribbon 2 can be partially or completely located in the groove 3. When the solder ribbon 2 is completely located in the groove 3, the bending height of the solder ribbon 2 when connecting adjacent cells is minimized, which can better reduce the stress between the cell and the solder ribbon. This improves the voltage and power output of the photovoltaic module. The groove 3 can increase the light absorption area and improve the conversion efficiency of the photovoltaic module. The fine grid 4 can reduce charge recombination losses and improve the current output of the photovoltaic module.

[0032] In the above optional embodiments, the first and second solar cells are usually made of silicon material, the most common of which are monocrystalline silicon, polycrystalline silicon and amorphous silicon. By converting light energy into electrical energy, the conversion and utilization of solar energy are realized. Under illumination, light energy will excite electrons inside the solar cell to generate current, thereby generating electrical energy. It is the core component of the photovoltaic module and the key to realizing solar energy conversion.

[0033] In the above optional embodiments, the solder ribbon is usually a strip material made of aluminum or copper, which connects the solar cells with the bracket, cables and other components to form the circuit of the photovoltaic module. It has good conductivity and corrosion resistance, which can ensure the stable and reliable electrical connection of the photovoltaic module. At the same time, it can also withstand a certain mechanical load, ensuring the stability and safety of the photovoltaic module during use. The selection of materials and processing quality of the solder ribbon has a great influence on the performance and life of the photovoltaic module. Therefore, special attention needs to be paid to the quality control of the solder ribbon.

[0034] In the above optional embodiments, the fine grid is usually made of metal wire or semiconductor material and is disposed on the surface of the solar cell. The fine grid and the main grid or solder strip form a grid-like structure, which can help the transmission of photons inside the solar cell and guide the photons to the photoelectric conversion layer, thereby improving the photoelectric conversion efficiency. In addition, the fine grid can reduce reflection and scattering, increase the light absorption rate, and enable the solar panel to effectively generate electricity in the low light environment.

[0035] In some alternative implementations, such as Figure 2 and Figure 3 As shown, both the front and back sides are provided with multiple spaced grooves 3.

[0036] In the above optional implementations, such as Figure 2 and Figure 3As shown, when multiple battery cells are connected in parallel using solder ribbons 2, the solder ribbons 2 may melt when heated, and may come into contact with the solder ribbons 2 on the back of the battery, which may lead to a short circuit between the battery cells. When grooves 3 are provided on both the front and back of the battery cells, the positions of the grooves 3 on the front and back can be staggered; the positions of the grooves 3 on the front and back can also be set one-to-one. This arrangement can minimize the distance between the solder ribbons 2 located in the grooves 3 on the front and the grooves 2 located in the grooves 3 on the back, thereby minimizing the bending degree of the solder ribbons when connecting different battery cells.

[0037] In some alternative embodiments, the first and second solar cells further include multiple main grids, with at least some of the main grids located in the grooves in a one-to-one correspondence, and the solder strips located on the side of the main grids away from the grooves.

[0038] In the above-mentioned optional embodiments, the main grid of the photovoltaic module with the main grid is set in the groove of the cell, and the main grids of multiple cells are electrically connected by solder ribbon. The main grid is usually composed of conductive silver wire or aluminum wire. The main grid can converge the current of multiple fine grids to form a current path between cells. The design and arrangement of the main grid have an important impact on the performance and efficiency of the photovoltaic module, and can affect the output power and stability of the photovoltaic module.

[0039] like Figure 2 and Figure 3 As shown, the battery cells in the battery string 1 have grooves 3 on the front and back main grid positions. During welding, the solder strip 2 is partially inserted into the groove 3. This welding method reduces the relative height between the batteries and increases the angle between the solder strip 2 on the front of the previous cell and the solder strip 2 on the back of the next cell. That is, the solder strip 2 becomes flatter, reducing the stress of the solder strip 2 on the battery and reducing microcracks in the battery.

[0040] It should be noted that the above-mentioned solar cell can be without a main grid or with a main grid. In the case of no main grid, the solder ribbon replaces the main grid and gathers the current in multiple fine grids. The extension direction of the groove is defined as a first direction, which is perpendicular to the extension direction of the fine grids in a second direction. The main grid is parallel to the solder ribbon.

[0041] In some alternative embodiments, the first and / or second cell includes a plurality of sub-cells, and solder ribbons are also connected to the main grids of the plurality of sub-cells in the first cell and / or solder ribbons are also connected to the main grids of the plurality of sub-cells in the second cell.

[0042] In the above optional embodiments, the first and / or second solar cells can also be small cell strings, dividing the first and / or second solar cells into multiple sub-cells, and connecting the main grids of these sub-cells with solder ribbons. This can improve the electrical connection between the cells, ensure that the current can flow effectively between the sub-cells, and thus improve the overall efficiency and performance of the photovoltaic module. The solder ribbons directly affect the quality of the electrical connection between the cells. If the solder ribbon connection is not firm or there is poor contact, it may lead to obstruction of current transmission. The solder ribbons are precisely designed to effectively connect the main grids of each sub-cell, ensuring that the solder ribbons play a good role in the photovoltaic module.

[0043] In some alternative implementations, such as Figure 1 and Figure 4 As shown, the photovoltaic module also includes a buffer structure 5, which is located between the groove wall and the solder strip 2.

[0044] In the above optional implementations, such as Figure 4 As shown, a buffer structure 5 is provided at the battery interconnection point, that is, near the edge of the battery cell. The order in which the buffer structure 5 and the solder ribbon 2 are laid can be as follows: the buffer structure 5 is pre-set on the battery cell interconnection side, and the solder ribbon 2 is laid for welding after the buffer structure 5 is set. Because of the buffer structure 5, the stress between the solder ribbon 2 and the battery is buffered, reducing the risk of battery microcracks caused by excessive stress between the solder ribbon 2 and the battery cell. By setting the buffer structure 5 in the groove, the microcrack rate of photovoltaic modules during the production process is further reduced, and the module yield is improved.

[0045] like Figure 3 and Figure 4 As shown, the aforementioned welding strip 2 is located on the front and / or back of the battery string 1. The portion located at the edge of the battery can be directly placed on the buffer structure 5. The buffer structure 5 is elastic when heated and can wrap the welding strip 2 to disperse the stress acting on the welding strip 2.

[0046] It should be noted that the above-mentioned buffer structure can be a film, and the material of the film can be either light-cured adhesive or thermosetting adhesive. The thickness of the buffer structure can be 0.01mm to 0.3mm.

[0047] In some alternative implementations, such as Figure 4 As shown, the buffer structure 5 is located in the edge region of the first and second battery cells, and the edge region is located at both ends of the groove in the length direction.

[0048] In the above optional implementations, such as Figure 4As shown, the aforementioned buffer structure 5 is located at the edge of the photovoltaic module and is used to protect the edge of the module from the influence of the external environment. It also plays a role in reducing the stress on the edge of the module and increasing the strength and stability of the module. It is usually made of silicone or other elastic materials and has good weather resistance and heat resistance. It can resist the corrosion of the module by external environment such as ultraviolet rays, high temperature, and humidity. In addition, the edge buffer structure 5 can also absorb and disperse the pressure on the edge of the module, reducing the risk of module damage caused by external forces.

[0049] In some alternative embodiments, the minimum distance between the aforementioned edge region and the two ends of the groove is 1 mm to 3 mm.

[0050] In the above optional embodiments, the buffer structure is located 1 to 3 mm away from the edge of the battery. By maintaining the minimum distance between the edge area and the groove, it can be ensured that the photovoltaic module will not crack or be damaged due to stress concentration during use, thereby improving the stability and reliability of the module.

[0051] In some optional embodiments, the maximum width of the buffer structure in the first direction is 0.3 mm to 1.5 mm, the maximum width in the second direction is 1 mm to 5 mm, and the thickness of the buffer structure is 0.05 mm to 0.3 mm.

[0052] In the above optional embodiments, the length of the buffer structure ranges from 1 to 5 mm, and the width ranges from 0.3 to 1.5 mm, so that the size of the buffer structure is small and the thickness is small, which ensures the overall lightweight of the photovoltaic module while providing sufficient support and stability for the solder strip.

[0053] In some alternative embodiments, the above-described buffer structure includes an adhesive material.

[0054] In the above optional embodiments, the buffer structure may include adhesive materials such as silicone, polyurethane adhesive, photocurable adhesive and acrylic adhesive, which have good bonding performance and weather resistance, and can effectively fix and seal the edges of photovoltaic modules to prevent the intrusion of moisture and dust, thereby improving the stability and durability of photovoltaic modules.

[0055] In some alternative implementations, the above-described buffer structure also includes an elastic material.

[0056] In the above optional embodiments, the buffer structure may also include elastic materials such as rubber, silicone and foam plastic, which have good elasticity and wear resistance, provide buffering and protection, and can effectively reduce the impact of external impacts on photovoltaic modules and extend their service life.

[0057] In some alternative implementations, such as Figure 5As shown, the maximum depth d of the groove is 5μm to 10μm, and the width D of the groove is 0.20mm to 0.30mm.

[0058] In the above optional implementations, such as Figure 5 As shown, the depth of the groove is d, and the dimension d should meet the requirement of 5 to 10 μm. The width is D, and the dimension D should meet the requirement of 0.20 to 0.30 mm.

[0059] The photovoltaic modules obtained through the above-mentioned cell interconnection method employ a technology that sets a buffer structure at the cell interconnection point. The buffer structure is composed of photocurable adhesive, thermocurable adhesive, or adhesive film. By precisely controlling the position and size of the buffer structure, the stress between the solder ribbon and the cell is effectively reduced, microcracks in the cell are reduced, and the module yield is improved. At the same time, grooves are set at the main grid positions on the front and back of the cell, and the solder ribbon is partially inserted into the grooves, which reduces the relative height between cells and the stress effect of the solder ribbon on the cell, further reducing the microcrack rate. This improves the stability and reliability of the photovoltaic module during the production process, resulting in better module welding performance, reduced production costs, and improved overall module performance and power generation efficiency.

[0060] The technical solutions of this application can be used in passivated emitter back contact cells (PERC), tunnel oxide passivated contact cells (TOPCON), heterojunction cells (HJT), back contact cells (BC), perovskite solar cells (PSC), etc., using gridless (OBB, Zero Busbar) or multi-busbar (MBB) technologies.

[0061] The photovoltaic module described above in this application will be specifically described below with reference to specific embodiments and comparative examples.

[0062] Example 1

[0063] This embodiment provides a photovoltaic module, including:

[0064] The first and second battery cells have a groove on their front surfaces, which extends along a first direction. The first and second battery cells include multiple fine grids, which are spaced apart on the front and back surfaces and extend along a second direction perpendicular to the first direction. The distance between the groove and the edge region of the first and second battery cells is 1 mm, the depth of the groove is 5 μm, and the width is 0.2 mm.

[0065] Multiple solder strips, some of which are located in the groove, connect the front side of the first battery cell and the back side of the second battery cell.

[0066] Example 2

[0067] This embodiment provides a photovoltaic module, including:

[0068] The first and second battery cells have a groove on their front surfaces, which extends along a first direction. The first and second battery cells include multiple fine grids, which are spaced apart on the front and back surfaces and extend along a second direction perpendicular to the first direction. The distance between the groove and the edge region of the first and second battery cells is 1 mm, the depth of the groove is 8 μm, and the width is 0.2 mm.

[0069] Multiple solder strips, some of which are located in the groove, connect the front side of the first battery cell and the back side of the second battery cell.

[0070] Example 3

[0071] This embodiment provides a photovoltaic module, including:

[0072] The first and second battery cells have a groove on their front surfaces, which extends along a first direction. The first and second battery cells each include multiple fine grids, which are spaced apart on the front and back surfaces and extend along a second direction perpendicular to the first direction. The distance between the groove and the edge region of the first and second battery cells is 1 mm, the depth of the groove is 10 μm, and the width is 0.2 mm.

[0073] Multiple solder strips, some of which are located in the groove, connect the front side of the first battery cell and the back side of the second battery cell.

[0074] Example 4

[0075] This embodiment provides a photovoltaic module, including:

[0076] The first and second battery cells have a groove on their front surfaces, which extends along a first direction. The first and second battery cells include multiple fine grids, which are spaced apart on the front and back surfaces and extend along a second direction perpendicular to the first direction. The distance between the groove and the edge region of the first and second battery cells is 1 mm, the depth of the groove is 5 μm, and the width is 0.25 mm.

[0077] Multiple solder strips, some of which are located in the groove, connect the front side of the first battery cell and the back side of the second battery cell.

[0078] Example 5

[0079] This embodiment provides a photovoltaic module, including:

[0080] The first and second battery cells have a groove on their front surfaces, which extends along a first direction. The first and second battery cells each include multiple fine grids, which are spaced apart on the front and back surfaces and extend along a second direction perpendicular to the first direction. The distance between the groove and the edge region of the first and second battery cells is 1 mm, and the groove has a depth of 5 μm and a width of 0.3 mm.

[0081] Multiple solder strips, some of which are located in the groove, connect the front side of the first battery cell and the back side of the second battery cell.

[0082] Example 6

[0083] This embodiment provides a photovoltaic module, including:

[0084] The first and second battery cells have a groove on their front surfaces, which extends along a first direction. The first and second battery cells each include multiple fine grids, which are spaced apart on the front and back surfaces and extend along a second direction perpendicular to the first direction. The distance between the groove and the edge region of the first and second battery cells is 1 mm, and the groove has a depth of 5 μm and a width of 0.3 mm.

[0085] Multiple solder strips, some of which are located in the groove, connect the front side of the first battery cell and the back side of the second battery cell;

[0086] A buffer structure is located in the edge region of the first and second battery cells and at both ends of the groove in the extending direction. The width of the buffer structure in the first direction is 1 mm, the width in the second direction is 3 mm, the thickness of the buffer structure is 0.2 mm, and the material of the buffer structure is thermosetting adhesive.

[0087] Example 7

[0088] This embodiment provides a photovoltaic module, including:

[0089] The first and second battery cells have a groove on their front surfaces, which extends along a first direction. The first and second battery cells each include multiple fine grids, which are spaced apart on the front and back surfaces and extend along a second direction perpendicular to the first direction. The distance between the groove and the edge region of the first and second battery cells is 1 mm, the depth of the groove is 2 μm, and the width is 0.1 mm.

[0090] Multiple solder strips, some of which are located in the groove, connect the front side of the first battery cell and the back side of the second battery cell.

[0091] Example 8

[0092] This embodiment provides a photovoltaic module, including:

[0093] The first and second battery cells have a groove on their front surfaces, which extends along a first direction. The first and second battery cells each include multiple fine grids, which are spaced apart on the front and back surfaces and extend along a second direction perpendicular to the first direction. The distance between the groove and the edge region of the first and second battery cells is 1 mm, and the groove has a depth of 5 μm and a width of 0.3 mm.

[0094] Multiple solder strips, some of which are located in the groove, connect the front side of the first battery cell and the back side of the second battery cell.

[0095] Example 9

[0096] A photovoltaic module is provided, comprising:

[0097] First solar cell and second solar cell;

[0098] Multiple solder strips, some of which are located in the groove, connect the front side of the first battery cell and the back side of the second battery cell;

[0099] A buffer structure is located in the edge region of the first and second battery cells and at both ends of the groove in the extending direction. The width of the buffer structure in the first direction is 0.3 mm, the width in the second direction is 1 mm, the thickness of the buffer structure is 0.05 mm, and the material of the buffer structure is thermosetting adhesive.

[0100] Comparative Example 1

[0101] This embodiment provides a photovoltaic module, including:

[0102] The first and second battery cells include multiple fine grids, which are spaced apart on the front and back sides.

[0103] Multiple solder strips connect the front side of the first battery cell and the back side of the second battery cell.

[0104] The performance of the photovoltaic modules using Examples 1-9 and Comparative Example 1 was tested, and the test results are as follows:

[0105] Table 1

[0106] Hidden crack rate % Example 1 5％ Example 2 3.8％ Example 3 3.2％ Example 4 4％ Example 5 3.6％ Example 6 3.5％ Example 7 5.7％ Example 8 4.0％ Example 9 3.9％ Comparative Example 1 10.0％

[0107] The experimental data in the table above show that the microcrack rate in Examples 1 to 6 is significantly higher than that in Examples 7 to 9, indicating that limiting the depth and width of the grooves in this application can significantly improve the microcrack rate of the cells. The microcrack rate in Examples 1 to 9 is significantly higher than that in Comparative Example 1, indicating that the technical solution of designing grooves on the cells in this application can significantly improve the impact of stress generated by the interconnection between cells on the cells in the prior art. The experimental data above show that the photovoltaic modules in this application have a low microcrack rate, which can ensure the integrity of the cell structure and improve the performance of the photovoltaic modules.

[0108] As can be seen from the above description, the embodiments of this application achieve the following technical effects:

[0109] 1) The photovoltaic module using the embodiments of this application has grooves on the front and / or back of the solar cells, and solder ribbons are arranged in the grooves. The minimum thickness of the solar cells is reduced, so that when the solder ribbons are connected to the front and back of multiple solar cells, the bending angle of the solder ribbons is smaller and more gradual, thereby reducing the stress between the solar cells and the solder ribbons, and making the connection between the solar cells and the solder ribbons more stable and reliable. This solves the problem in related technologies where the small spacing between solar cells leads to an increased bending height of the solder ribbons, causing the solar cells to break during lamination.

[0110] 2) The photovoltaic module described in this application has a buffer structure set at both ends in the groove extension direction, which can further disperse the stress acting on the solder strip and the edge of the cell, and reduce the risk of microcracks in the cell.

[0111] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0112] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A photovoltaic module, characterized in that, include: Multiple battery strings, each battery string including at least a first battery cell and a second battery cell, the first battery cell and the second battery cell having a front side and a back side, the front side and / or the back side having a groove extending along a first direction, the first battery cell and the second battery cell including multiple fine grids, the fine grids being spaced apart on the front side and the back side, the fine grids extending along a second direction perpendicular to the first direction, the maximum depth of the groove being 5μm~10μm, the width of the groove being 0.20mm~0.30mm, the grooves on the front side and the back side being staggered; Multiple solder strips, some of which are located in the groove, connect the front side of the first battery cell and the back side of the second battery cell.

2. The photovoltaic module according to claim 1, characterized in that, Both the front and the back sides are provided with multiple spaced grooves.

3. The photovoltaic module according to claim 1, characterized in that, The first and second battery cells also include multiple main grids, at least some of which are located in the grooves in a one-to-one correspondence, and the solder strips are located on the side of the main grids away from the grooves.

4. The photovoltaic module according to claim 1, characterized in that, The first battery cell and / or the second battery cell include a plurality of sub-cells, and the solder ribbon also connects the main grids of the plurality of sub-cells in the first battery cell and / or the solder ribbon also connects the main grids of the plurality of sub-cells in the second battery cell.

5. The photovoltaic module according to any one of claims 1 to 4, characterized in that, The photovoltaic module also includes a buffer structure located between the groove wall and the solder strip.

6. The photovoltaic module according to claim 5, characterized in that, The buffer structure is located in the edge region of the first battery cell and the second battery cell, and the edge region is located at both ends of the groove in the length direction.

7. The photovoltaic module according to claim 6, characterized in that, The minimum distance between the edge region and the two ends of the groove is 1mm to 3mm.

8. The photovoltaic module according to claim 5, characterized in that, The buffer structure has a maximum width of 0.3mm to 1.5mm in the first direction, a maximum width of 1mm to 5mm in the second direction, and a thickness of 0.05mm to 0.3mm.

9. The photovoltaic module according to claim 5, characterized in that, The buffer structure includes an adhesive material.

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