A method of manufacturing a photovoltaic module
Patent Information
- Application Number
- CN202611344389.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-09-01
- Publication Date
- 2026-10-27
AI Technical Summary
第（2）种技术方案，由于焊接在层压过程完成，只能在层压后进行检测，当光伏组件存在虚焊、隐裂等问题时，无法进行返修
[0033]总体而言，通过本申请所构思的以上技术方案与现有技术相比，能够取得下列有益效果。
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Figure FT_1
Abstract
Description
Technical Field
[0001] This invention relates to the field of photovoltaic technology, and specifically provides a method for preparing a photovoltaic module. Background Technology
[0002] Currently, there are several technical solutions for the manufacturing process of photovoltaic modules. (1) First, multiple single cells are interconnected and welded into independent cell strings, then multiple cell strings are arranged into a whole matrix, and the cell strings are welded to the busbars to complete the series / parallel connection of the cell strings, and then the whole module is laminated and encapsulated. (2) Multiple cells and corresponding welding strips are fixed in strings with laminating film, then multiple strings and busbars are arranged into a whole module on the laminated substrate, and then the upper layer of laminated substrate is arranged for lamination and encapsulation, and welding is completed at the same time by relying on the high temperature of lamination and encapsulation. (3) First, the whole module of cells, welding strips, and busbars are arranged on the laminated substrate, and the whole module is welded by means of laser or other methods, and then the upper layer of laminated substrate is arranged for lamination and encapsulation.
[0003] Among them, the first technical solution requires handling before and after the battery string is welded, which can easily cause microcracks in the battery cells. The second technical solution, since the welding is completed during the lamination process, can only be inspected after lamination. When the photovoltaic module has problems such as poor welding or microcracks, it cannot be reworked. The third technical solution can be inspected before lamination and encapsulation. However, when faced with problems such as poor welding or microcracks that require rework, how to carry out the rework is a problem faced by those skilled in the art. Summary of the Invention
[0004] In view of the above-mentioned problems in the prior art, the present invention proposes a method for preparing photovoltaic modules.
[0005] This invention provides a method for preparing a photovoltaic module, comprising the following steps:
[0006] 1) Arrange the solar cells and interconnects on the bottom plate and the bottom layer adhesive film arranged from bottom to top, and fix the interconnects and solar cells to prepare a photovoltaic module semi-finished product, wherein the interconnects are solder ribbons, or solder ribbons and busbars; in this step, the bottom surface of the solar cells is bonded to the bottom layer adhesive film;
[0007] 2) Inspect the semi-finished photovoltaic modules, including EL testing, and identify the unqualified cells and corresponding unqualified cell strings detected by EL testing;
[0008] 3) Remove the defective battery string and the underlying adhesive film from the base plate;
[0009] 4) Replace with a qualified battery string and the underlying adhesive film;
[0010] 5) Place the top layer of encapsulant and the top plate on top of the photovoltaic module semi-finished product in sequence, and laminate and encapsulate to obtain the photovoltaic module.
[0011] Following the above method, step 3) removes the defective battery string and its underlying adhesive film from the base plate. This involves cutting the underlying adhesive film corresponding to the defective battery string and then removing the defective battery string and its underlying adhesive film from the base plate.
[0012] According to the above method, in step 1), the bottom adhesive film is composed of multiple independently set adhesive film segments spliced together, and at least one independently set adhesive film segment is set under each battery string. In step 3), removing the unqualified battery string and the bottom adhesive film below it from the base plate means directly removing the unqualified battery string and the corresponding adhesive film segment below it from the base plate.
[0013] Using the above method, when the photovoltaic module is a full-screen segmented cell photovoltaic module, multiple cell strings connected in the extension direction of the cell string are regarded as a long cell string.
[0014] According to the above method, the battery is a back-contact battery, and when arranging the battery cells in step 1), the front of the battery is arranged downwards.
[0015] According to the above method, step 4) also includes a step of re-inspecting the photovoltaic module semi-finished product.
[0016] Following the above method, battery cells and interconnecting components are arranged on the bottom plate and bottom film arranged sequentially from bottom to top, and the interconnecting components and battery cells are fixed, which is to arrange and weld the battery cells and interconnecting components on the bottom plate and bottom film arranged sequentially from bottom to top.
[0017] According to the above method, the interconnecting components in step 1) are solder strips and busbars;
[0018] Step 2) involves performing EL testing on the semi-finished photovoltaic modules.
[0019] Step 3) After removing the busbar connected to the defective battery string from the defective battery string, remove the defective battery string and the underlying adhesive film below it from the base plate.
[0020] Step 4) After replacing the qualified battery string and its underlying adhesive film, weld the replaced qualified battery string and busbar together.
[0021] Alternatively, the interconnecting element in step 1) is a solder strip.
[0022] The EL testing in step 2) involves performing EL testing on the cell strings of the photovoltaic module semi-finished product;
[0023] Step 4) After replacing the battery string with a qualified battery string and the underlying adhesive film, the steps also include arranging and welding the busbars.
[0024] Following step 3) of the above method, step 601) is also included, which involves removing the solder strips from the defective battery cells on the defective battery string, replacing the defective battery cells with qualified battery cells and welding them together to form a qualified battery string.
[0025] Following step 601), the method described above also includes step 602, which involves performing EL testing on the qualified battery string.
[0026] According to the above method, step 601) specifically involves unsoldering the solder strips on the defective battery cell, replacing the defective battery cell with a qualified battery cell, and resoldering the unsoldered solder strips.
[0027] Following the above method, step 3) removes the busbar connected to the defective battery string from the defective battery string, which is to desolder the busbar connected to the defective battery string; step 4) welds the replacement qualified battery string and the busbar, which is to re-weld the qualified battery string and the desoldered busbar.
[0028] According to the above method, in step 1), the battery cells and interconnects are arranged and welded on the bottom plate and bottom film arranged from bottom to top. Specifically, the flexible film is covered with the arranged battery cells and interconnects, and a vacuum is drawn to press the flexible film tightly against the interconnects and battery cells. The laser passes through the flexible film for welding.
[0029] Following the method described above, the battery cells and interconnects are arranged and welded together.
[0030] Arrange the battery cells and solder strips and weld them together;
[0031] Alternatively, after arranging the battery cells, arrange the solder strips and busbars, and then weld them simultaneously;
[0032] Alternatively, some of the solder strips and busbars can be prefabricated. After arranging the battery cells, the solder strips and prefabricated solder strips and busbars can be arranged and then welded simultaneously.
[0033] Overall, the above-described technical solutions conceived in this application can achieve the following beneficial effects compared with the prior art.
[0034] The photovoltaic module manufacturing method of the present invention arranges and fixes the cells and interconnects on the bottom film to achieve electrical connection. Then, EL detection can be performed above the cell string to identify unqualified cells and their corresponding cell strings. Then, qualified cell strings with the bottom film below directly replace the unqualified cell strings with the bottom film below. Finally, the photovoltaic module is laminated and encapsulated to obtain the photovoltaic module. This enables the detection and rapid rework of the photovoltaic module before lamination, ensuring the yield of the final photovoltaic module. Attached Figure Description
[0035] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0036] Figure 1 This is a schematic flowchart of the photovoltaic module manufacturing method of the present invention. Detailed Implementation
[0037] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.
[0038] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. It should be noted that, unless otherwise specified, the various features in the embodiments of this application can be combined with each other, and the combined embodiments are still within the protection scope of this application.
[0039] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application 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 on this application. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0040] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection and alignment of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0041] This invention provides a method for preparing a photovoltaic module, comprising the following steps:
[0042] 1) Arrange solar cells and interconnects on a base plate and a bottom layer of adhesive film arranged sequentially from bottom to top, and fix the interconnects and solar cells to prepare a semi-finished photovoltaic module. The interconnects are solder ribbons, or solder ribbons and busbars. In this step, the bottom surface of the solar cells is bonded to the laminated adhesive film.
[0043] 2) Inspect the semi-finished photovoltaic modules, including EL testing, and identify the unqualified cells and corresponding unqualified cell strings detected by EL testing.
[0044] 3) Remove the defective battery string and the underlying adhesive film from the base plate.
[0045] 4) Replace with a qualified battery string and the underlying adhesive film.
[0046] 5) Place the top layer of encapsulant and the top plate on top of the photovoltaic module semi-finished product in sequence, and laminate and encapsulate to obtain the photovoltaic module.
[0047] The photovoltaic module manufacturing method of this invention achieves electrical connection by arranging and fixing the cells and interconnects on the bottom film. EL detection can be performed above the cell string to identify unqualified cells and their corresponding cell strings. Then, qualified cell strings with the bottom film below can directly replace the unqualified cell strings with the bottom film below. Finally, lamination and encapsulation are performed to obtain the photovoltaic module. This enables the detection and rapid rework of the photovoltaic module before lamination, ensuring the final yield of the photovoltaic module.
[0048] In a method for manufacturing a photovoltaic module according to the present invention, in step 1), the interconnecting components and the solar cells are preferably fixed by welding. Since the welding temperature is higher than the melting temperature of the underlying adhesive film, the bottom surface of the solar cell, i.e., the side in contact with the underlying adhesive film, is bonded and fixed to the underlying adhesive film during the welding process. In other embodiments, the fixing can also be done by bonding with conductive adhesive, as long as electrical connection can be achieved. In such embodiments, the fixing process does not cause the bottom surface of the solar cell to be bonded and fixed to the underlying adhesive film. However, after the solar cells are arranged and before the interconnecting components are arranged, the solar cells are heated and bonded to the underlying adhesive film to prevent movement, and the bottom surface of the solar cells is also bonded and fixed to the underlying adhesive film. It is understood that when the fixing is done by welding, the bottom surface of the solar cell can also be pre-bonded and fixed to the underlying adhesive film.
[0049] When performing EL testing in step 2), the test can be performed on one side of the top surface of the cell, that is, the side away from the bottom film. Specifically, EL testing can be performed on the welded cell string or the entire photovoltaic module semi-finished product with welded busbars.
[0050] In some embodiments, in the photovoltaic module manufacturing method of the present invention, in step 1), the interconnecting element may be only a solder ribbon. In this step, only the battery cells and solder ribbon are arranged and welded. Alternatively, the interconnecting element may be a solder ribbon and a busbar. In this step, the battery cells, solder ribbon, and busbar are arranged and welded.
[0051] Specifically, on the bottom film, the solar cells and interconnects are arranged sequentially according to the module layout. More specifically, the solar cells are back-contact cells, with their front (bottom) side (non-electrode side) facing down on the bottom film and in contact with it, and their back (top) side (electrode side) facing up. The interconnects are arranged above the solar cells in the form of cell strings or series and parallel connections between cell strings. Solder strips are welded to the solar cells to form cell strings. Busbars and solder strips are then welded together to complete the series or parallel connection of the cell strings.
[0052] This invention does not limit the specific order of arrangement and welding of the solar cells, solder ribbons, and busbars. For example, the solar cells and solder ribbons can be arranged and welded, followed by the arrangement and welding of the busbars. Alternatively, the solar cells, solder ribbons, and busbars can be arranged and welded. Of course, for full-screen photovoltaic modules, i.e., photovoltaic modules with adjacent solar cells stacked together, the busbars and connecting solder ribbons can be prefabricated, and welding can be performed after the arrangement of the solar cells, solder ribbons, and prefabricated busbars is completed. Of course, other methods are also possible, as long as the arrangement and welding can be completed.
[0053] In step 1), welding can be laser welding. Specifically, as one possible implementation, after arranging the battery cells and interconnects, a flexible film is placed over them. The projected area of the flexible film on the laminated adhesive film surface exceeds the laminated adhesive film, and the edges of the flexible film are fixed (e.g., fixed to a worktable below the laminated adhesive film). Then, a vacuum is drawn into the space covered by the flexible film, causing the flexible film to press the interconnects and battery cells tightly. Then, a laser shines through the flexible film onto the interconnects, completing the welding. As mentioned earlier, the interconnects can be solder ribbons. After the aforementioned welding, busbars are arranged, and then the busbars are welded. Of course, the interconnects can also be solder ribbons and busbars. Alternatively, the arrangement of busbars (or prefabricated busbars) can be completed simultaneously when arranging the battery cells and solder ribbons, and the welding can be completed by covering them with a flexible film during the welding process.
[0054] In step 2), EL testing of the photovoltaic module semi-finished product can be performed using EL testing equipment. This equipment applies a forward bias current to the cell string or photovoltaic module semi-finished product and uses a camera for detection. In qualified areas, the current flows smoothly, the recombination is sufficient, and the image is bright and uniform. Areas with microcracks, broken grids, poor soldering, fragments, or inefficient cells will appear black, dark, or have black spots and lines. This identifies the unqualified cells and the cell string containing them; the cell string is then considered unqualified.
[0055] In some implementations, step 3) involves removing the defective battery string and the underlying adhesive film from the substrate, specifically including the following methods.
[0056] In some implementations, the bottom adhesive film is a whole sheet of bottom adhesive film. To remove the defective battery string and the bottom adhesive film below it, the corresponding bottom adhesive film below the defective battery string is cut and separated from the whole adhesive film. Then, the defective battery string and its corresponding bottom adhesive film are removed together from the base plate, leaving a gap at the corresponding position on the base plate.
[0057] In another embodiment, the bottom adhesive film is composed of multiple independently arranged adhesive film segments assembled together. Each battery string has one independent adhesive film segment underneath it, although multiple independent adhesive film segments can also be used. In this embodiment, removing the defective battery string and its corresponding bottom adhesive film segment from the base plate is much more convenient, as it can be done directly without cutting the bottom adhesive film.
[0058] Step 4) Replace the defective battery string and its underlying adhesive film with a qualified battery string. Typically, the bottom of the replaced qualified battery string is also bonded to the underlying adhesive film. In practice, this can come from two sources. One source is that during step 3), in addition to removing the defective battery string and its corresponding underlying adhesive film, the qualified battery string and its corresponding underlying adhesive film can also be removed one by one. This qualified battery string and its corresponding underlying adhesive film can then be used as replacements for the qualified battery string and its underlying adhesive film in subsequent photovoltaic module manufacturing processes. Using this method can improve the efficiency of photovoltaic module manufacturing.
[0059] Another source is the compliant battery strings and their underlying adhesive film obtained from the rework of defective battery strings. Specifically, after removing the defective battery strings and their underlying adhesive film from the substrate, the solder ribbons on the defective cells in the defective battery strings are removed, and the defective cells are replaced with compliant cells and welded together to form compliant battery strings. Understandably, the compliant battery strings and their underlying adhesive film obtained from the rework can be directly replaced in this process for better compatibility, or they can be reserved for replacement in subsequent photovoltaic module manufacturing, which can also improve the manufacturing efficiency of photovoltaic modules.
[0060] Thus, in some embodiments, after step 3), step 601) is included, which involves removing the solder ribbons from the defective cells in the defective battery string, replacing the defective cells with qualified cells, and then welding them together to form a qualified battery string. In some specific embodiments, removing the solder ribbons from the defective cells in the defective battery string specifically involves desoldering the solder ribbons from the defective cells; replacing the defective cells with qualified cells and then re-welding them using the desoldered solder ribbons. This method facilitates the rework of the battery string. Alternatively, the solder ribbons of the defective cells can be removed, replaced with qualified cells, and then welded using new solder ribbons. Regardless of the method, the rework of the photovoltaic battery string is performed while the underlying encapsulant film is still attached. During subsequent replacement, the reworked battery string and its underlying encapsulant film can be easily replaced.
[0061] In some preferred embodiments, after step 601), a step 602) is included to perform EL testing on the reworked battery string to determine whether it is qualified. Generally, after rework in step 601), the battery string is usually qualified. However, it is possible that microcracks may have occurred due to improper operation during the rework process, resulting in poor EL performance of the battery string. Therefore, after rework, EL testing is performed to determine whether it is qualified before replacement.
[0062] In another embodiment, after replacing the qualified battery string and its underlying encapsulant film in step 4), the process may further include performing EL testing on the photovoltaic module semi-finished product again. If the test is passed, the subsequent process continues; if it still fails, step 3 is repeated.
[0063] As mentioned above, in step 1), the interconnecting components can be solder strips and busbars. In step 1), the arrangement and welding of the busbars are completed simultaneously.
[0064] Correspondingly, in step 2), the entire semi-finished photovoltaic module can be subjected to EL testing.
[0065] Meanwhile, step 3) involves removing the busbar connected to the defective battery string from the defective battery string, and then removing the defective battery string and the underlying adhesive film below it from the base plate.
[0066] Step 4) After replacing the qualified battery string and the underlying adhesive film below it, weld the replaced qualified battery string and busbar together.
[0067] In some implementations, step 3) involves removing the busbar connected to the defective battery string from the defective battery string, or desoldering the busbar connected to the defective battery string; in step 4), the replacement qualified battery string and the busbar are soldered together, or the qualified battery string and the desoldered busbar are re-soldered together. Of course, step 3) can also involve completely removing the busbar connected to the defective battery string, and then soldering a new busbar in step 4).
[0068] In another embodiment, in step 1), the interconnect is a solder strip, and correspondingly, in step 2), each cell string of the semi-finished photovoltaic module is subjected to EL testing.
[0069] Step 4) After replacing the battery string with a qualified battery string and the underlying adhesive film, the process also includes arranging busbars and welding them.
[0070] In some preferred embodiments, in step 1), photovoltaic glass or photovoltaic backsheet can be used as the base plate, and in step 5), photovoltaic glass can be used as the top plate, so that lamination encapsulation can be performed directly.
[0071] It should be noted that in steps 2) and 3), the defective battery string and its underlying adhesive film, and the qualified battery string and its underlying adhesive film, refer to the underlying adhesive film set for the corresponding battery string. This can be the underlying adhesive film directly below it, or a slightly larger one. Slight differences in size between the replaced and removed underlying adhesive films will not have an impact, because in step 5), during lamination and encapsulation, the underlying adhesive film will melt and flow, eventually filling and completing the lamination process evenly.
[0072] Furthermore, it should be noted that the description of the top and bottom surfaces of the solar cells in this invention refers to their state during the photovoltaic module manufacturing process, not their state during use. During this manufacturing process, the back-contact cells are arranged with the front side facing down and the back side facing up to facilitate arrangement and welding. The "top" and "bottom" in the bottom film, top film, bottom plate, and top plate refer to their state before lamination and encapsulation. During lamination, the cells can be flipped over, and they are used according to requirements.
[0073] It should be noted that the photovoltaic module of the present invention can be a full-screen photovoltaic module. In some full-screen photovoltaic modules, that is, in some photovoltaic modules with stacked cells, a long string can be set in the extension direction of the cell string, that is, two or more cell strings in the extension direction of the cell string are set with zero or negative spacing, and connected by solder strips and busbars. In this case, this long string can be regarded as a cell string and reworked.
[0074] It is understood that the photovoltaic module manufacturing method of the present invention also includes junction box lead wires, etc. Any improved technical solutions not of the present invention are existing technologies and will not be described in detail here.
[0075] The above description is merely an optional embodiment of this application and is not intended to limit 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 protection scope of this application.
Claims
1. A method for preparing a photovoltaic module, characterized in that: Includes the following steps, 1) Arrange the solar cells and interconnects on the bottom plate and the bottom layer adhesive film arranged from bottom to top, and fix the interconnects and solar cells to prepare a photovoltaic module semi-finished product, wherein the interconnects are solder ribbons, or solder ribbons and busbars; in this step, the bottom surface of the solar cells is bonded to the bottom layer adhesive film; 2) Inspect the semi-finished photovoltaic modules, including EL testing, and identify the unqualified cells and corresponding unqualified cell strings detected by EL testing; 3) Remove the defective battery string and the underlying adhesive film from the base plate; 4) Replace with qualified battery strings and the underlying adhesive film; 5) Place the top layer of encapsulant and the top plate on top of the photovoltaic module semi-finished product in sequence, and laminate and encapsulate to obtain the photovoltaic module.
2. The method for preparing a photovoltaic module according to claim 1, characterized in that: Step 3) Remove the defective battery string and the underlying adhesive film below it from the base plate. This involves cutting the underlying adhesive film below the defective battery string and then removing the defective battery string and the underlying adhesive film below it from the base plate.
3. The method for preparing a photovoltaic module according to claim 1, characterized in that: In step 1), the bottom adhesive film is composed of multiple independently set adhesive film segments spliced together, and at least one independently set adhesive film segment is set under each battery string. In step 3), the defective battery string and the bottom adhesive film below it are removed from the base plate, which means that the defective battery string and the corresponding adhesive film segment below it are directly removed from the base plate.
4. The method for preparing a photovoltaic module according to claim 1, characterized in that: When the photovoltaic module is a full-screen segmented cell photovoltaic module, multiple cell strings connected in the extension direction of the cell string are regarded as a single cell string.
5. The method for preparing a photovoltaic module according to claim 1, characterized in that: The battery is a back-contact battery, and in step 1), when arranging the battery cells, the front of the battery is facing down.
6. The method for preparing a photovoltaic module according to claim 1, characterized in that: Step 4 also includes a step of re-inspecting the photovoltaic module semi-finished product.
7. The method for preparing a photovoltaic module according to any one of claims 1 to 6, characterized in that: The battery cells and interconnects are arranged on the bottom plate and the bottom film arranged from bottom to top, and the interconnects and battery cells are fixed. The battery cells and interconnects are arranged on the bottom plate and the bottom film arranged from bottom to top and then welded.
8. The method for preparing a photovoltaic module according to claim 7, characterized in that: The interconnecting components in step 1) are solder strips and busbars; Step 2) involves performing EL testing on the semi-finished photovoltaic modules. Step 3) After removing the busbar connected to the defective battery string from the defective battery string, Remove the defective battery string and the underlying adhesive film from the base plate; Step 4) After replacing the qualified battery string and its underlying adhesive film, weld the replaced qualified battery string and busbar together. Alternatively, the interconnecting element in step 1) is a solder strip. The EL testing in step 2) involves performing EL testing on the cell strings of the photovoltaic module semi-finished product; Step 4) After replacing the battery string with a qualified battery string and the underlying adhesive film, the steps also include arranging and welding the busbars.
9. A method for preparing a photovoltaic module according to claim 7, characterized in that: After step 3), the process also includes step 601), which involves removing the solder strips from the defective battery cells in the defective battery string, replacing the defective battery cells with qualified battery cells, and soldering them together to form a qualified battery string.
10. A method for preparing a photovoltaic module according to claim 9, characterized in that: After step 601), there is also step 602, which is the step of performing EL testing on qualified battery strings.
11. A method for preparing a photovoltaic module according to claim 9, characterized in that: Step 601) Specifically involves unsoldering the solder strips on the defective battery cell, replacing the defective battery cell with a qualified battery cell, and resoldering the unsoldered solder strips.
12. A method for preparing a photovoltaic module according to claim 8, characterized in that: Step 3) Remove the busbar connected to the defective battery string from the defective battery string, which is to desolder the busbar connected to the defective battery string; Step 4) Weld the replacement qualified battery string and busbar, which is to re-weld the qualified battery string and the desoldered busbar.
13. A method for preparing a photovoltaic module according to claim 7, characterized in that: Step 1) Arrange and weld the battery cells and interconnects on the bottom plate and bottom film arranged from bottom to top. Specifically, cover the arranged battery cells and interconnects with a flexible film, and draw a vacuum to press the flexible film tightly against the interconnects and battery cells. The laser passes through the flexible film for welding.
14. A method for preparing a photovoltaic module according to claim 13, characterized in that: Arrange the battery cells and interconnects and weld them together. Arrange the battery cells and solder strips and weld them together; Alternatively, after arranging the battery cells, arrange the solder strips and busbars, and then weld them simultaneously; Alternatively, some of the solder strips and busbars can be prefabricated. After arranging the battery cells, the solder strips and prefabricated solder strips and busbars can be arranged and then welded simultaneously.