Solar cell string manufacturing method and photovoltaic module

Abstract

The application provides a solar cell string preparation method and a photovoltaic module. The preparation method comprises the following steps: providing a solar cell and a conductor; laying the conductor on the solar cell, and bending the conductor to form a first abutting surface and a second abutting surface opposite to each other, wherein the solar cell comprises a front surface and a back surface arranged opposite to each other, and the front surface or the back surface of the solar cell is provided with a plurality of main grids, and the first abutting surface and the second abutting surface are used for abutting the front surface and the back surface of two adjacent solar cells, respectively; welding the laid solar cell and the conductor; and sequentially performing a mask process, an etching process and a demasking process on the welded solar cell and the conductor to form a solar cell string. In this way, the conductor plays the role of a solder strip, and the solder strip is not needed to be arranged, the conductor is accurately aligned and stably connected with the super-dense main grid, the risk of current transmission loss caused by poor welding is significantly reduced, and the overall performance and reliability of the solar cell string are improved.

Description

Technical Field

[0001] This application relates to the field of solar cell fabrication technology, and in particular to a method for fabricating solar cell strings and a photovoltaic module. Background Technology

[0002] In the current photovoltaic industry, current harvesting in solar cells primarily relies on the main busbar and sub-busbar. From early 3BB and 5BB technologies to SMBB, these technologies achieve current harvesting through different shapes and numbers of grid lines. To further improve current harvesting efficiency, the currently popular OBB technology concentrates the grid lines on the main busbar, eliminating the sub-busbar and retaining an ultra-dense main busbar design. This approach aims to improve current harvesting efficiency while simplifying the cell structure. However, ultra-dense main busbars make it difficult to ensure effective alignment of the solder ribbon. The solder ribbon is a key component used for welding the main busbar; if it is not accurately aligned, it will lead to poor welding and affect the normal transmission of current. If this problem cannot be solved, it will limit the application effect of OBB technology in actual production.

[0003] It should be noted that the above content is not necessarily prior art, nor is it intended to limit the scope of patent protection of this application. Summary of the Invention

[0004] This application provides a solar cell string and its fabrication method, as well as a photovoltaic module, to solve the problem that the solder ribbon is difficult to align with the ultra-dense grid during the fabrication of solar cell strings using existing ultra-dense grid solutions, thereby preventing secondary problems such as poor welding and impact on current transmission.

[0005] As one aspect of the embodiments of this application, this application provides a method for preparing a solar cell string, the method comprising:

[0006] Provides solar cells and conductors;

[0007] The conductor is laid on the solar cell. The conductor is bent and includes a first abutting surface and a second abutting surface opposite each other. The solar cell includes a front side and a back side opposite each other. The front side or the back side of the solar cell is provided with multiple main grids. The first abutting surface and the second abutting surface are respectively used to abut the front side and the back side of two adjacent solar cells.

[0008] The solar cells and the conductors are welded together after installation;

[0009] The welded solar cells and the conductor are sequentially subjected to a masking process, an etching process, and a mask removal process to form a solar cell string;

[0010] When the front or back of the solar cell is projected onto the plane containing the first or second contact surface, its projected image can be completely contained within the first or second contact surface.

[0011] Optionally, the solar cell has a main grid area to be plated on the front or back side, and the main grid is located in the main grid area to be plated and abuts against the first contact surface or the second contact surface.

[0012] Optionally, the main gate includes a main gate seed layer and a main gate conductive layer, the main gate seed layer is attached to the main gate to be plated area, and the main gate conductive layer is away from the main gate to be plated area.

[0013] Optionally, the main gate seed layer includes at least one of silver, nickel, copper, aluminum, and tin.

[0014] Optionally, the conductor includes a welding portion and a substrate portion, the welding portion being disposed close to the main gate and the substrate portion being disposed away from the main gate.

[0015] Optionally, the substrate portion is configured as copper foil with a thickness of 0.05~0.1mm.

[0016] Optionally, the mask is a photoresist or a polymer.

[0017] Optionally, in the etching process, the etching solution is applied by dripping onto the conductor.

[0018] As another aspect of the embodiments of this application, this application provides a photovoltaic module, including a solar cell string prepared by the solar cell string preparation method described above, and further including an encapsulation layer and a cover plate. The encapsulation layer is placed on one side of the solar cell string, and the cover plate is placed on the side of the encapsulation layer away from the solar cell string, and the three are laminated together.

[0019] The embodiments of this application employing the above-described technical solution may have the following advantages:

[0020] This application provides a method for fabricating a solar cell string and a photovoltaic module, aiming to effectively solve the problem of aligning the solder ribbon with the ultra-dense grid when using an ultra-dense grid scheme in the prior art. The method for fabricating a solar cell string includes providing solar cells and conductors; laying the conductor on the solar cells, the conductor being bent and configured to include opposing first and second abutment surfaces; the solar cells including opposing front and back sides, with multiple grids on the front or back side of the solar cells; the first and second abutment surfaces respectively abutting the front and back sides of two adjacent solar cells; welding the laid solar cells and conductors together; and sequentially performing a masking process, an etching process, and a mask removal process on the welded solar cells and conductors to form a solar cell string; when the front or back side of the solar cells is projected onto the plane containing the first or second abutment surface, its projected pattern can be completely accommodated within the first or second abutment surface. In this configuration, the conductor acts as a solder ribbon, eliminating the need for additional solder ribbons, achieving precise alignment and stable connection between the conductor and the ultra-dense grid, thereby significantly reducing the risk of current transmission loss due to poor welding and improving the overall performance and reliability of the cell string. This interconnect structure employs a unique geometric layout, enhancing mechanical stability and providing strong support for the long-term, high-efficiency operation of photovoltaic modules. Furthermore, this solution considers compatibility with existing production processes, making it easy to integrate into existing production lines and contributing to the photovoltaic industry's development towards higher efficiency and lower costs. Attached Figure Description

[0021] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the various drawings denote the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed in this application and should not be construed as limiting the scope of this application.

[0022] Figure 1 This is a schematic diagram of a solar cell planar structure using an ultra-dense grid scheme provided in an embodiment of this application.

[0023] Figure 2 This is a three-dimensional structural diagram of the conductive material for laying a solar cell provided in an embodiment of this application;

[0024] Figure 3 This is a graphical schematic diagram of the solar cell masking process provided in the embodiments of this application;

[0025] Figure 4 A plan view of the etching process performed on the solar cell string provided in the embodiments of this application;

[0026] Figure 5 This is a schematic diagram of the process for fabricating a solar cell string according to an embodiment of this application.

[0027] Explanation of reference numerals in the attached figures:

[0028] 1-Solar cell; 11-First cell; 12-Second cell; 2-Main grid; 3-Conductor; 31-First contact surface; 32-Second contact surface; 4-Mask layer; 5-Solder. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other. The application will now be described in detail with reference to the accompanying drawings and embodiments.

[0030] It should be noted that the terms "first," "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 terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a 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.

[0031] In this application, the term "numerical interval" (i.e., numerical range) refers to a range of values. Unless otherwise specified, the distribution of selectable values ​​within this numerical interval is considered continuous, and includes the two endpoints (i.e., the minimum and maximum values) of the interval, as well as every value between these endpoints. Unless otherwise specified, when a numerical interval refers only to integers within that interval, it includes the two endpoints of the range and every integer between them, effectively listing every integer. When multiple numerical ranges are provided to describe features or characteristics, these ranges can be merged. In other words, unless otherwise specified, the numerical ranges disclosed in this application should be understood to include any and all subranges included therein. The "numerical value" in this numerical interval can be any quantitative value, such as a number, percentage, or proportion. The term "numerical interval" can broadly include percentage intervals, proportion intervals, ratio intervals, and other quantitative intervals.

[0032] Exemplary embodiments according to this application will now be described in more detail with reference to the accompanying drawings. It should be understood that these exemplary embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein.

[0033] This application discloses a photovoltaic module, including a solar cell string, an encapsulation layer, and a cover plate. The encapsulation layer is placed on one side of the solar cell string, and the cover plate is placed on the side of the encapsulation layer away from the solar cell string. The three are laminated together.

[0034] The following provides a further description of the solar cell string; please refer to it as well. Figure 1 and Figure 2 This application discloses a solar cell string using an ultra-dense main grid scheme. The cell string includes a conductor 3 and a solar cell 1. The solar cell 1 includes a front and a back side arranged opposite each other. Multiple main grids 2 are provided on the front or back side, with no secondary grids. The main grids 2 are used to collect the current collected by the solar cell 1. In this application embodiment, the solar cell 1 can use technologies such as TOPCon, HJT, and PERC (TOPCon stands for Tunnel Oxide Passivated Contact; HJT stands for Heterojunction Technology; PERC stands for Passivated Emitter and Rear Cell). The conductor 3 is bent and includes opposing first contact surfaces 31 and second contact surfaces 32, such as... Figure 2 As shown, for ease of description, two adjacent solar cells 1 are defined as the first cell 11 and the second cell 12, respectively. The conductor 3 is bent, and the first contact surface 31 of the conductor 3 is defined as... Figure 2 The non-visible surface, the second contact surface 32 is Figure 2 In the context of the visible surfaces, the visible surface of the first battery 11 is defined as the front, and the invisible surface as the back. Figure 2It can be seen that the back of the first battery 11 abuts against the second abutting surface 32 of the preceding conductor 3, and the front of the first battery 11 abuts against the first abutting surface 31 of the following conductor 3. Similarly, the back of the second battery 12 abuts against the second abutting surface 32 of the following conductor 3, and the front of the second battery 12 abuts against the first abutting surface 31 of the next following conductor 3, and so on. Since the conductor 3 is bent, one conductor 3 can abut against two solar cells 1 and maintain the same thickness, reducing the packaging difficulty. Preferably, when the front or back of the solar cell 1 When projected onto the plane containing the first contact surface 31 or the second contact surface 32, the projected pattern can be completely contained within the first contact surface 31 or the second contact surface 32. That is, the surface area of ​​the front or back of the solar cell 1 is less than or equal to half the surface area of ​​the first contact surface 31 or the second contact surface 32. With this configuration, the conductor 3 acts as a solder ribbon, eliminating the need for additional solder ribbons. This achieves precise alignment and stable connection between the conductor 3 and the ultra-dense grid 2, significantly reducing the risk of current transmission loss due to poor welding and improving the overall performance and reliability of the cell string. This interconnection structure employs a unique geometric layout, enhancing mechanical stability and providing strong support for the long-term high-efficiency operation of photovoltaic modules. Furthermore, this solution considers compatibility with existing production processes. The bent conductor 3 is easy to integrate into existing production lines, which not only helps maintain the thickness consistency of the solar cell string and reduces encapsulation difficulty but also enhances the mechanical stability of the entire interconnection structure, contributing to the development of the photovoltaic industry towards higher efficiency and lower costs.

[0035] Specifically, the front or back of the solar cell 1 is provided with a grid-to-plate area. In this embodiment, the number of grids 2 is 176, and the number of grid-to-plate areas is the same as the number of grids 2. Each grid 2 is located in a grid-to-plate area and abuts against the first contact surface 31 or the second contact surface 32, which can achieve precise alignment and stable connection between the conductor 3 and the ultra-dense grid 2, effectively reducing the risk of current transmission loss due to poor welding, thereby improving the overall performance and reliability of the battery string. The grid 2 includes a grid seed layer and a grid conductive layer. The main grid seed layer is attached to the main grid area to be plated, and the main grid conductive layer is away from the main grid area to be plated. The conductor 3 includes a welding part and a substrate part. The welding part is located close to the main grid 2, and the substrate part is away from the main grid 2. The conductor 3 is used to connect the front and back of adjacent cells and to collect the current of the solar cell string onto the bus bar. After the conductor 3 is applied to the solar cell 1, by adding solder 5 and using infrared heating, the solder 5 is interconnected with the welding part of the conductor 3 and the main grid conductive layer, which further enhances the stability and conductivity of the connection.

[0036] Furthermore, the main grid seed layer includes at least one of silver, nickel, copper, aluminum, and tin. These metals all have good conductivity and solderability, providing a good foundation for subsequent welding, ensuring welding quality, reducing contact resistance, improving current collection efficiency, and enhancing battery performance. In this embodiment, the substrate of the conductor 3 is copper foil with a thickness of 0.05~0.1mm. This is because copper has excellent conductivity and good mechanical properties, which can effectively reduce the resistance of the conductor 3 and reduce losses during current transmission. At the same time, the thickness of the copper foil is between 0.05~0.1mm, which ensures that the conductor 3 has sufficient mechanical strength so that it is not easily broken or deformed during the preparation and use of the battery string, while minimizing the thickness of the conductor 3, reducing shading of the battery cells, and improving the photoelectric conversion efficiency of the photovoltaic module. In addition, the appropriate thickness also facilitates the bending and shaping of the conductor 3, which is beneficial to achieving precise alignment and stable connection between the conductor 3 and the ultra-dense main grid 2.

[0037] Furthermore, such as Figure 2 As shown, the definition Figure 2 The horizontal dimension is the length, and the conductor length is: solar cell length * 2 + the distance between two adjacent solar cells 1; preferably, the conductor length is: solar cell length * 2 + the distance between two adjacent solar cells - the distance between the main grid and the edge of the solar cell * 2, which can reduce shading and increase the light-receiving area.

[0038] This application also provides a method for fabricating a solar cell string, applicable to the solar cell string described above. Please refer to [link to relevant documentation]. Figure 5 The preparation method includes:

[0039] S1. Prepare the solar cell.

[0040] Specifically, multiple solar cells 1 using an ultra-dense grid scheme need to be prepared, and a corresponding number of conductors 3 need to be prepared according to the number of solar cells 1.

[0041] S2, Laying the conductor.

[0042] like Figure 2As shown, a conductor 3 is laid on the solar cell 1. The conductor 3 includes a first abutment surface 31 and a second abutment surface 32, which are respectively used to abut the front and back sides of two adjacent solar cells 1. The conductor 3 is bent, which not only helps to maintain the uniform thickness of the solar cell string and reduces the difficulty of subsequent encapsulation processes, but also enhances the mechanical stability of the entire interconnection structure. When the front or back side of the solar cell 1 is projected onto the plane where the first abutment surface 31 or the second abutment surface 32 is located, its projected pattern can be completely contained within the first abutment surface 31 or the second abutment surface 32. That is, the surface area of ​​the front or back side of the solar cell 1 is less than or equal to half the surface area of ​​the first abutment surface 31 or the second abutment surface 32. With this setting, the conductor 3 acts as a solder ribbon, eliminating the need for additional solder ribbons. This achieves precise alignment and stable connection between the conductor 3 and the ultra-dense grid 2, thereby significantly reducing the risk of current transmission loss due to poor welding and improving the overall performance and reliability of the battery string. In this embodiment, the substrate of the conductor 3 is a copper foil with a thickness of 0.05~0.1mm.

[0043] S3, Welding process.

[0044] By adding solder 5 and using infrared heating, solder 5 interconnects with the welding part of conductor 3 and the main grid conductive layer, further enhancing the stability and conductivity of the connection. It is understandable that high-temperature processes such as laser welding can also be used. In this case, solder 5 is not needed, as the welding temperature of conductor 3 can be reached directly, and conductor 3 and main grid 2 can be welded together. For conventional infrared heating welding methods, tin-lead solder is used for solder 5. If the high temperature effect is considered, tin-lead-bismuth or tin-lead-bismuth-silver solder can be used, with a thickness of 0.02~0.05mm. The main purpose is to weld conductor 3 and the lower main grid 2, with the width ideally consistent with the main grid 2. In actual operation, the appropriate welding method and solder 5 should be selected according to the specific process conditions and material characteristics to ensure welding quality. Regardless of the welding method used, it is necessary to carefully control the welding temperature and time to avoid damage to solar cell 1 and conductor 3, while ensuring that the strength and conductivity of the welded part meet the requirements to guarantee the stability and reliability of the battery string. In addition, the selected welding process should be compatible with subsequent packaging processes to ensure the smooth operation of the entire production process.

[0045] S4, Masking process.

[0046] like Figure 3 As shown, Figure 3This is a schematic diagram illustrating the masking process for a solar cell provided in this application embodiment. First, a masking material, such as photoresist or polymer, is selectively coated onto the surface of the solar cell 1. The shape and position of the mask follow a predetermined patterned layout, typically corresponding to the main grid 2 of the solar cell 1, to ensure protection of the main grid 2 area during subsequent etching. Then, an etching resist layer is generated in the patterned area of ​​the mask layer 4 using inkjet printing or laser direct writing technology. The etching resist layer is composed of acid and alkali resistant ink. The size and shape of the mask layer 4 need to be designed appropriately to ensure that the etching solution works at a certain distance from the center of the main grid 2, thereby preventing uneven formation of the copper substrate. The width of the mask layer 4 is designed to be greater than or equal to the main grid 2 of the solar cell 1 to ensure that the main grid 2 is adequately protected during etching and can form a good connection with the conductor 3 in subsequent steps. The purpose of the masking process is to provide a precise patterned template for subsequent etching processes, retaining the patterned structure of the main grid 2 during etching while removing unwanted copper foil portions to form a patterned structure of the copper substrate. The formation of a mask does not depend on specific data, but is achieved through the rational control of material properties and process parameters.

[0047] S5, Etching process.

[0048] like Figure 4 As shown, Figure 4 This is a schematic plan view of the etching process for the solar cell string provided in the embodiments of this application, showing the application of an acidic or alkaline etching solution along... Figure 4 The etching solution is dripped onto the conductor 3 in the inner A direction using a drop-drip method. The solution can be acidic or alkaline, and its specific formulation will be selected based on the material of the mask layer 4 and the conductor 3. Since the substrate of the conductor 3 in this embodiment is copper foil, the etching solution in this embodiment needs to ensure effective etching of the copper foil without reacting with the film layer on the surface of the solar cell 1. The mask layer 4 area, protected by the resist layer, will not react with the etching solution, and therefore the material beneath it will not be etched. In areas not covered by the mask layer 4, the etching solution will react with the conductor 3. Because the etching rate is consistent in all directions, the etched area will exhibit a circular pattern that spreads outwards, ultimately forming a shape resembling... Figure 4 The diagram shows a triangular conductive structure. By optimizing the etching solution formulation, the etching rate can be increased, and the resulting triangle's apex angles can be made sharper. Sharp apex angles help improve the optical utilization of the component, reducing light obstruction by the solder ribbon and allowing reflected light to reach the cell surface more effectively.

[0049] Specifically, the etching solution in this embodiment contains multiple components, such as benzotriazole (BTA), which can react with the underlying material (such as ITO or SiN). XThe metal oxides on the surface form coordination bonds (Cu-BTA binding energy is approximately 1.8 eV), thereby inhibiting the penetration of the etching solution and ensuring the precision of the etching process. In addition, the etching solution also contains Fe. 3+ It preferentially oxidizes copper (E o (Fe 3+ / Fe 2 + ) = 0.77V, E o (Cu 2+ / Cu)=0.34V), while for silicon (E) o (Si / SiO2) = -0.86V) indicates no oxidation, further protecting the solar cell from damage. The etching solution formulation may include FeCl3·6H2O as the main etchant to oxidize Cu to Cu. 2+ Benzotriazole (BTA) is used to adsorb onto non-copper surfaces to form a protective film; citric acid is used to complex free Fe. 3+ To prevent precipitation, HCl is used to adjust the pH value between 1.5 and 2.5. These components work synergistically to ensure an efficient and precise etching process. The entire etching process is achieved through the rational formulation of the etching solution and precise control of process parameters, without relying on specific data, only ensuring that the etching effect meets the design requirements. After etching, the resulting conductive structure provides a good electrical connection foundation for subsequent solar cell string encapsulation, while also optimizing the optical performance of the module.

[0050] like Figure 4 As shown, the structure of the etched conductor 3 is approximately triangular. In order to increase the optical utilization rate, the thickness of the copper foil and the width of the mask can be adjusted, which can adjust the apex angle of the triangle formed. Generally, the optimal angle is ≤46°, and the edge curve formed by etching is closest to a straight line. At this time, the optical utilization rate is closest to 100%.

[0051] S6, Mask removal process.

[0052] As mentioned in step S3, the resist layer of mask layer 4 is an acid and alkali resistant ink, which can be removed in this step using chemical or mechanical methods after the etching process. The reason for removing mask layer 4 is that its main function is to protect the main grid 2 area during etching, preventing it from being eroded by the etching solution, thereby ensuring the integrity of the main grid 2 and the precise connection of the conductors 3. After the etching process, the presence of mask layer 4 may affect subsequent encapsulation processes and the overall performance of the solar cell string. After removing mask layer 4, the surface of solar cell 1 can be more smoothly and tightly bonded to other encapsulation materials, avoiding problems such as poor adhesion or bubbles caused by mask layer 4 residue, thereby improving the reliability and durability of the photovoltaic module. Furthermore, removing mask layer 4 also ensures the cleanliness of the surface of solar cell 1, which is beneficial for subsequent optical performance optimization, reducing light reflection and scattering, and improving the photoelectric conversion efficiency of the module. Therefore, removing mask layer 4 is an important step in ensuring the quality of the cell string and the performance of the photovoltaic module.

[0053] S7, in strings.

[0054] The final fabrication of the solar cell string, achieved using the above steps, offers several significant advantages. First, the string achieves precise alignment and stable connection between the conductor 3 and the ultra-dense grid 2, significantly reducing the risk of current transmission loss due to poor welding and effectively improving the overall performance and reliability of the string. Second, because the conductor 3 is bent, one conductor 3 can connect to two solar cells 1 while maintaining the same thickness, thus reducing encapsulation difficulty. Third, the string eliminates the need for additional solder ribbons; the conductor 3 acts as the solder ribbon, simplifying the fabrication process, reducing material usage, and contributing to lower production costs and increased efficiency. Furthermore, optimized etching and mask layer 4 removal ensure a clean and smooth cell surface, facilitating subsequent encapsulation processes and improving the photovoltaic module's photoelectric conversion efficiency and long-term stability. Finally, the entire fabrication process fully considers compatibility with existing production processes, making it easy to integrate into existing production lines and promoting the photovoltaic industry towards higher efficiency and lower costs.

[0055] In summary, the embodiments of this application provide a method for preparing a solar cell string and a photovoltaic module, which aims to effectively solve the problem of aligning the solder strips with the ultra-dense busbar when using an ultra-dense busbar scheme in the prior art. The method for fabricating a solar cell string of the present invention includes providing solar cells and conductors; laying the conductors on the solar cells, the conductors being bent and configured to include opposing first and second abutment surfaces; the solar cells including opposing front and back sides, the front or back side of the solar cells having multiple main grids; the first and second abutment surfaces being used to abut the front and back sides of two adjacent solar cells respectively; welding the laid solar cells and conductors together; and sequentially performing a masking process, an etching process, and a mask removal process on the welded solar cells and conductors to form a solar cell string; when the front or back side of the solar cells is projected onto the plane containing the first or second abutment surface, its projected pattern can be completely accommodated within the first or second abutment surface. With this configuration, the conductors 3 act as solder strips, eliminating the need for additional solder strips, achieving precise alignment and stable connection between the conductors 3 and the ultra-dense main grids 2, thereby significantly reducing the risk of current transmission loss due to poor welding and improving the overall performance and reliability of the cell string. This interconnection structure employs a unique geometric layout, enhancing mechanical stability and providing strong support for the long-term efficient operation of photovoltaic modules. In addition, this solution takes into account compatibility with existing production processes, making it easy to integrate into existing production lines and helping to drive the photovoltaic industry toward higher efficiency and lower costs.

[0056] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0057] For ease of description, directional terms such as "front, back, up, down, left, right," "horizontal, vertical, horizontal," and "top, bottom" generally indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. These terms are used solely for the purpose of facilitating the description of this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the referred mechanism or element must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the scope of protection of this application. The directional terms "inner" and "outer" refer to the inner or outer contours relative to the components themselves. For example, if a device in the drawings is inverted, a device described as "above" or "on top of" other devices or structures will subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein are interpreted accordingly.

[0058] Unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0059] Unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0060] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0061] It should also be noted that the terms "one embodiment," "another embodiment," and "embodiment" used in this specification refer to specific features, structures, or characteristics described in connection with that embodiment, which are included in at least one embodiment described in the general description of this application. The appearance of the same expression in multiple places in the specification does not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in connection with any embodiment, the intention is to suggest that implementing such a feature, structure, or characteristic in conjunction with other embodiments also falls within the scope of this application.

[0062] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0063] It should also be noted that the above are merely preferred embodiments of this application and do not limit the scope of patent protection of this application. Any equivalent structural or procedural changes made using the content of this application’s specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of this application.

Claims

1. A method of fabricating a solar cell string, characterized by, The preparation method comprises: providing a solar cell and a conductor; applying the conductor to the solar cell, the conductor being arranged in a bent manner, comprising opposite first and second abutting surfaces, the solar cell comprising opposite front and back surfaces, the front or back surface of the solar cell being provided with a plurality of main grids, the first and second abutting surfaces being used for abutting the front and back surfaces of two adjacent solar cells respectively, and when the front or back surface of the solar cell is projected onto a plane in which the first or second abutting surface is located, the projection pattern can be completely contained in the first or second abutting surface; welding the applied solar cell and the conductor; sequentially performing a mask process, an etching process and a demasking process on the welded solar cell and the conductor to form a solar cell string; in the etching process, the etching liquid is dropped and sprinkled on the conductor.

2. The production method according to claim 1, characterized by, The front or back surface of the solar cell is provided with a main grid plating area, and the main grid is arranged in the main grid plating area and abuts against the first or second abutting surface.

3. The preparation method according to claim 2, characterized in that, The main grid comprises a main grid seed layer and a main grid conductive layer, the main grid seed layer is attached to the main grid plating area, and the main grid conductive layer is away from the main grid plating area.

4. The production method according to claim 3, characterized by, The main grid seed layer comprises at least one of silver, nickel, copper, aluminum and tin.

5. The production method according to any one of claims 1 to 4, characterized by, The conductor comprises a welding portion and a base material portion, the welding portion is arranged close to the main grid, and the base material portion is away from the main grid.

6. The production method according to claim 5, wherein The base material portion is configured as a copper foil with a thickness of 0.05-0.1 mm.

7. The preparation method according to claim 1, characterized in that, The mask is photoresist or polymer.

8. A photovoltaic module, characterized by, The solar cell string prepared by the preparation method of the solar cell string according to any one of claims 1-7 further comprises an encapsulation layer and a cover plate, the encapsulation layer is placed on the surface of one side of the solar cell string, the cover plate is placed on the surface of the side of the encapsulation layer away from the solar cell string, and the three are laminated and formed.

Images