Photovoltaic module and method of manufacturing the same

Abstract

This application relates to the photovoltaic field, providing a photovoltaic module and its manufacturing method. The photovoltaic module includes at least one battery cell group, which includes at least three battery cells connected in parallel via busbars. The at least three battery cells include at least one first battery cell and at least two second battery cells, or at least two first battery cells and at least one second battery cell. Each first battery cell includes at least two first battery strings connected in series, each first battery string including one or more first battery cells connected in series. Each second battery cell includes at least two second battery strings connected in series, each second battery string including one or more second battery cells connected in series. The number of battery cells is odd. The first battery cells are divided into n1 segments, and the second battery cells are divided into n2 segments, with n1 and n2 being a multiple of each other. The photovoltaic module provided by this application can at least reduce electrical losses and increase output power.

Description

Technical Field

[0001] This application relates to the field of photovoltaics, and in particular to a photovoltaic module and its preparation method. Background Technology

[0002] With the continuous development of photovoltaic technology, high-efficiency, low-cost, and high-reliability photovoltaic modules have become the core direction of industrial development. Currently, mainstream photovoltaic modules generally use half-cell cells for arrangement. Among them, half-cell cells have become the market leader due to their advantages such as reducing series resistance, improving anti-shading ability, and improving temperature coefficient. Their typical structure is a configuration of two parallel and three strings or three parallel and four strings, combined with three bypass diodes to achieve partial shading protection.

[0003] However, most traditional photovoltaic modules use single-size cells for encapsulation, meaning that the size of the cells—whole cells, half cells, or quarter cells—remains completely consistent within a single module. While this design simplifies the manufacturing process, in terms of power output, half-cell modules, although highly reliable, have lower power output, while quarter-cell modules have higher power output but are structurally complex and have greater losses. It is difficult to optimize the two in a coordinated manner. Summary of the Invention

[0004] This application provides a photovoltaic module and its manufacturing method, which at least helps to improve the problem of power loss and increased cost caused by the use of single-size solar cells in traditional photovoltaic modules, which leads to complex jumper and diode structures.

[0005] According to some embodiments of this application, one aspect of this application provides a photovoltaic module, including at least one battery cell group, the battery cell group including at least three battery cells connected in parallel through a busbar, the at least three battery cells including at least one first battery cell and at least two second battery cells, or at least two first battery cells and at least one second battery cell;

[0006] The first battery unit includes at least two first battery strings connected in series, and each first battery string includes one or more first battery cells connected in series; the second battery unit includes at least two second battery strings connected in series, and each second battery string includes one or more second battery cells connected in series.

[0007] The number of battery cells is odd; the first battery cell is an n1 segment cut from a whole battery cell, and the second battery cell is an n2 segment cut from a whole battery cell, with n1 and n2 being a multiple of each other.

[0008] In some embodiments, there is one first battery cell and two second battery cells, and n1 is twice n2.

[0009] In some embodiments, the first battery cell is located on the side of a second battery cell away from another second battery cell, and the first battery cell is connected in parallel with a first bypass diode;

[0010] The second battery cell is connected in parallel with a second bypass diode, and the two second bypass diodes are connected to the busbar through the same jumper; or, the ends of the two second battery cells away from the busbar are connected together, and the two second battery cells are simultaneously connected in parallel with second bypass diodes.

[0011] In some embodiments, the first battery cell is located between two second battery cells; the first battery cell is connected in parallel with a first bypass diode, the second battery cell is connected in parallel with a second bypass diode, and the two second bypass diodes are respectively connected to the busbar via jumpers.

[0012] In some embodiments, a first battery unit is located between two second battery units; the first battery unit includes two first battery strings arranged in parallel, with each end of the first battery string connected in parallel to the corresponding second battery unit, and a second bypass diode connected in parallel to the second battery unit, the bypass diode being connected to the busbar through the first battery string.

[0013] In some embodiments, there are two first battery cells and one second battery cell, and n1 is twice n2.

[0014] In some embodiments, the second battery cell is located on the side of one first battery cell away from the other; the first battery cell is connected in parallel with a first bypass diode, the second battery cell is connected in parallel with a second bypass diode, and the second bypass diode is connected to the busbar via a jumper.

[0015] In some embodiments, the second battery cell is located between two first battery cells; the first battery cells are connected in parallel with a first bypass diode, the second battery cells are connected in parallel with a second bypass diode, and the second bypass diode is connected to the busbar via a jumper.

[0016] In some embodiments, one of n1 and n2 is half, and the other of n1 and n2 is one-quarter.

[0017] In some embodiments, the photovoltaic module further includes an encapsulating film and a cover plate, wherein the encapsulating film is used to cover the surfaces of the first and second battery strings; and the cover plate is used to cover the surface of the encapsulating film opposite to the first and second battery strings.

[0018] According to some embodiments of this application, another aspect of this application provides a method for preparing a photovoltaic module, applicable to the photovoltaic modules mentioned above. The preparation method includes:

[0019] Acquire the first and second battery cells;

[0020] The first battery cell and the second battery cell are connected in series to form at least two first battery strings and at least two second battery strings; and at least two first battery strings are connected in series to form a first battery unit and at least two second battery strings are connected in series to form a second battery unit.

[0021] At least one first battery cell and at least two second battery cells, or at least two first battery cells and at least one second battery cell, are connected in parallel via a busbar to form a battery cell group containing at least three battery cells.

[0022] Bypass diodes are configured for the first battery cell and the second battery cell, respectively;

[0023] In this configuration, at least one bypass diode of the second battery cell is connected to the busbar via a common jumper.

[0024] In some embodiments, the preparation method further includes:

[0025] The entire waste battery cell is cut once, and the waste part is removed to obtain the first battery cell with n1 segments;

[0026] The edge defects of the first battery cell are cut a second time to obtain the second battery cell with n2 segments;

[0027] The size of the second solar cell is half the size of the first solar cell.

[0028] The technical solution provided in this application has at least the following advantages:

[0029] By arranging solar cells of different specifications, the monotonous appearance of traditional photovoltaic modules caused by the single specification of the cells is effectively broken. Due to the complementarity of the electrical characteristics of different cell segments, this differentiated layout based on the multiple relationship (n1 and n2 are a multiple of each other) provides a technical basis for the secondary use of solar cells. When cutting a full cell to produce a half cell, if there is minor damage at the edge that prevents it from being used as a standard half cell, it can be further cut into n1 segments or n2 segments for mixing. This significantly reduces the loss rate caused by cell damage and gives photovoltaic modules a more diverse visual structure, meeting the demand for personalized appearance.

[0030] Furthermore, in terms of electrical performance and cost optimization, this technical solution effectively reduces the multiple jumpers and complex diode structures commonly found in traditional photovoltaic modules by rationally configuring the number and connection method of the first and second battery cells. Specifically, through a hybrid series-parallel structure, it can reduce contact resistance losses and potential hot spot risks caused by jumpers while maintaining the overall power output of the module. It can also reduce the number of diodes used (e.g., from three to two or zero), thereby lowering costs and simplifying the module manufacturing process. This, in turn, optimizes current distribution, improves the overall conversion efficiency of the module, and enables higher output power within the same area. This helps to address the problem of power loss and increased cost caused by the complex jumper and diode structures resulting from the use of single-size cells in traditional photovoltaic modules. Attached Figure Description

[0031] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Unless otherwise stated, the drawings in the accompanying drawings do not constitute a limitation on scale. In order to more clearly illustrate the technical solutions in the embodiments of this application or in the conventional art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 A schematic diagram of the structure of a photovoltaic module according to an embodiment of this application;

[0033] Figure 2 This is a schematic diagram of a second embodiment of a photovoltaic module provided in this application.

[0034] Figure 3 This is a schematic diagram of the structure of a photovoltaic module according to a third embodiment of this application.

[0035] Figure 4 This is a schematic diagram of the structure of a photovoltaic module according to Embodiment 4 of this application.

[0036] Figure 5 This is a schematic diagram of the structure of a photovoltaic module according to Embodiment 5 of this application.

[0037] Figure 6 This is a schematic diagram of a sixth embodiment of a photovoltaic module provided in this application.

[0038] 1. Battery cell pack; 2. Busbar; 3. Jumper wire;

[0039] 10. First battery cell; 11. First battery string; 110. First battery cell; 12. First bypass diode; 13. First battery array;

[0040] 20. Second battery cell; 21. Second battery string; 210. Second battery cell; 22. Second bypass diode. Detailed Implementation

[0041] As the background technology indicates, with the continuous development of photovoltaic technology, high-efficiency, low-cost, and high-reliability photovoltaic modules have become the core direction of industrial development. Currently, mainstream photovoltaic modules generally use half-cell cells for arrangement, with a typical structure of two parallel and three strings or three parallel and four strings, coupled with three bypass diodes to achieve partial shading protection. However, most traditional photovoltaic modules use single-specification cells for packaging, that is, the size of cells, whether full-cell, half-cell, or quarter-cell, remains completely consistent within a single module. This results in a situation where, in terms of power output, half-cell modules, although highly reliable, have lower power, while quarter-cell modules have higher power but a complex structure and greater losses, making it difficult to optimize the two in a coordinated manner.

[0042] This application provides a photovoltaic module and its manufacturing method.

[0043] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0044] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0045] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A exists, A and B exist simultaneously, and B exists. In addition, the character " / " in this document generally indicates that the related objects before and after it have an "or" relationship.

[0046] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0047] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0048] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" 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 or an electrical 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. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0049] In the accompanying drawings corresponding to the embodiments of this application, the thickness and area of ​​the layers are enlarged for better understanding and ease of description. When describing a component (such as a layer, film, region, or substrate) on or on the surface of another component, the component may be "directly" located on the surface of the other component, or there may be a third component between the two components. Conversely, when describing a component on the surface of another component, or when another component is formed or disposed on the surface of a component, it indicates that there is no third component between the two components. Furthermore, when describing a component as being "generally" formed on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor is it formed on a portion of the edge of the entire surface.

[0050] In the description of the embodiments of this application, when a component "includes" another component, other components are not excluded unless otherwise stated, and other components may be further included. Furthermore, when a component such as a layer, film, region, or plate is referred to as being "on / located" on another component, it can be "directly on" the other component (i.e., located on the surface of the other component with no other components between them), or another component may be present therein. Moreover, when a component such as a layer, film, region, or plate is "directly located" on another component, or when a component such as a layer, film, region, or plate is located on the surface of another component, it indicates that no other components are located therein.

[0051] The terminology used in the description of the various embodiments herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the description of the various embodiments and the appended claims, the term "part" is also intended to include the plural form unless the context clearly indicates otherwise. Components include layers, films, regions, or plates, etc.

[0052] The embodiments of this application will now be described in detail with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the embodiments of this application to facilitate a better understanding of the application. However, the technical solutions claimed in this application can be implemented even without these technical details and various variations and modifications based on the following embodiments.

[0053] Please refer to Figures 1 to 6 As shown, one embodiment of this application provides a photovoltaic module, including at least one battery cell group 1. The battery cell group 1 includes at least three battery cells connected in parallel via a busbar 2. The at least three battery cells include at least one first battery cell 10 and at least two second battery cells 20, or at least two first battery cells 10 and at least one second battery cell 20. The first battery cell 10 includes at least two first battery strings 11 connected in series, and the first battery string 11 includes one or more first battery cells 110 connected in series. The second battery cell 20 includes at least two second battery strings 21 connected in series, and the second battery string 21 includes one or more second battery cells 210 connected in series. The number of battery cells is odd. The first battery cell 110 is an n1 segment cut from a whole battery cell, and the second battery cell 210 is an n2 segment cut from a whole battery cell, with n1 and n2 being a multiple of each other.

[0054] By arranging solar cells of different specifications, the monotonous appearance of traditional photovoltaic modules caused by the single specification of the cells is effectively broken. Due to the complementarity of the electrical characteristics of different cell segments, this differentiated layout based on the multiple relationship (n1 and n2 are a multiple of each other) provides a technical basis for the secondary use of solar cells. When cutting a full cell to produce a half cell, if there is minor damage at the edge that prevents it from being used as a standard half cell, it can be further cut into n1 segments or n2 segments for mixing. This significantly reduces the loss rate caused by cell damage and gives photovoltaic modules a more diverse visual structure, meeting the demand for personalized appearance.

[0055] Furthermore, in terms of electrical performance and cost optimization, this technical solution effectively reduces the number of jumpers 3 and complex diode structures commonly found in traditional photovoltaic modules by rationally configuring the number and connection method of the first battery cell 10 and the second battery cell 20. Specifically, through a hybrid series-parallel structure, while maintaining the overall power output of the module, it can reduce the contact resistance loss and potential hot spot risk caused by the jumpers 3, and at the same time reduce the number of diodes used (e.g., from three to two or zero), thereby reducing costs and simplifying the module manufacturing process. This, in turn, optimizes the current distribution, improves the overall conversion efficiency of the module, and enables higher output power in the same area. This helps to address the problem of power loss and increased cost caused by the complex jumper 3 and diode structures resulting from the use of single-size cells in traditional photovoltaic modules.

[0056] Because defective products such as edge cracks, microcracks, and missing corners are inevitably produced during the traditional battery cutting process, these battery cells are directly discarded due to size discrepancies or appearance defects, resulting in low material utilization and resource waste.

[0057] This application designs the length of large-size solar cells to be twice that of small-size solar cells, without requiring all solar cells to be exactly the same size. For example, this ratio is satisfied between full cells and half cells, and between half cells and quarter cells. This design ensures compatibility in electrical series connection and physical arrangement for solar cells with different degrees of segmentation.

[0058] When a full-cell battery develops minor edge cracks, microcracks, or cosmetic defects during the cutting process into half-cells, rendering it unusable as a standard half-cell or failing power testing, it can be recut. This means the original waste battery slices can be reused and cut again. For example, if minor damage is found on the edge of a half-cell after cutting, it can be recut into quarters or more, reducing the loss rate. In this way, battery cells that were initially deemed waste due to minor defects are improved into smaller-sized cells, significantly reducing the cell loss rate during production, increasing material utilization, and avoiding resource waste and environmental burden caused by direct disposal.

[0059] In some embodiments, the number of first battery cells 10 is less than the number of second battery cells 20; there is one first battery cell 10 and two second battery cells 20, and n1 is twice n2.

[0060] For example, since the area of ​​the first battery cell 10 (e.g., half a cell) is twice that of the second battery cell 20 (e.g., quarter cell), i.e., n1 is twice n2, the current or voltage occupied by the first battery cell 10 in the series or parallel path is equivalent to the sum of the two second battery cells 20. This allows for the flexible mixing and use of quarter cells resulting from edge damage during full-cell cutting with intact standard half cells, while maintaining stable overall output power. This not only avoids the scrapping of entire cells due to minor defects, greatly improving the overall utilization rate of the cells, but also reduces raw material costs and increases the utilization rate of scrap cells.

[0061] In traditional quad-cell modules, four small cells are typically connected via multiple jumpers (3). The large number of jumpers (3) and complex connection points easily introduce contact resistance and shading losses. In this embodiment, however, a large-cell-two-small-cell configuration is used. Two quad-cell units are connected in parallel via a simplified jumper (3) structure, and then combined with a half-cell unit in a series-parallel connection. This design reduces the total number of jumpers (3) and solder points, thereby reducing the risk of power degradation caused by jumpers (3) and improving the overall conversion efficiency of the photovoltaic module. Simultaneously, the simplified wiring structure also improves production efficiency and reduces the complexity and labor costs during the encapsulation process.

[0062] In Embodiment 1 of this application, as Figure 1 As shown, the first battery unit 10 is located on the side of one second battery unit 20 away from the other second battery unit 20. The first battery unit 10 is connected in parallel with a first bypass diode 12. The second battery unit 20 is connected in parallel with a second bypass diode 22. The two second bypass diodes 22 are connected to the bus bar 2 through the same jumper 3.

[0063] This embodiment effectively optimizes the electrical protection mechanism of the photovoltaic module and reduces power loss by improving the layout of the bypass diodes and the connection method of the jumper 3. Specifically, the first battery cell 10 (large battery, such as half cell) is an independent string with a single first bypass diode 12 connected in parallel; while the two second battery cells 20 (small battery, such as quarter cell) each have a second bypass diode 22 connected in parallel, but the output terminals of the two second bypass diodes 22 are connected to the busbar 2 through the same jumper 3.

[0064] This design allows the two small battery cells to form a tightly connected parallel group electrically. When one of the small battery cells is shaded or fails, the corresponding second bypass diode 22 conducts to protect that cell. Furthermore, since the two diodes share a jumper 3, the number of connection points in the overall structure is reduced, lowering the shading loss and contact resistance loss caused by multiple jumpers 3 running in parallel. Compared to the complex structure of traditional quad-cell modules where each pair of small battery cells has its own independent diode and jumper 3, this embodiment simplifies external wiring and improves the uniformity of current collection while ensuring that each small battery cell has an independent protection circuit, thereby improving the module's fill factor and overall conversion efficiency.

[0065] This layout also significantly improves the manufacturing yield and structural stability of photovoltaic modules. In traditional designs, the complex arrangement of jumpers 3 often leads to uneven stress on the solder ribbon during the lamination process, which can easily cause microcracks in the cells or breakage of the solder ribbon. In this embodiment, the diodes of the two second cell units 20 are connected through the same jumper 3, making the fixing points and stress distribution of this part of the circuit more concentrated and controllable during the encapsulation process. This not only reduces the risk of solder ribbon movement during the lamination process but also lowers the probability of open circuits or short circuits caused by process fluctuations. At the same time, the simplified jumper 3 structure allows for higher utilization of the internal space of the photovoltaic module, helps control the overall thickness of the photovoltaic module, improves the aesthetics and strength of the product, makes it more adaptable to various harsh environmental conditions, and extends its service life.

[0066] In Embodiment 2 of this application, as Figure 2 As shown, the first battery unit 10 is located on the side of one second battery unit 20 away from the other second battery unit 20, and the first battery unit 10 is connected in parallel with a first bypass diode 12; the ends of the two second battery units 20 away from the busbar 2 are connected together, and the two second battery units 20 are connected in parallel with a second bypass diode 22.

[0067] This embodiment significantly reduces the material cost of photovoltaic modules and simplifies the internal circuitry through a structural design of small cells connected in series and the entire module bypassed. Specifically, two second cell units 20 (e.g., quarter-cells) are directly connected in series end-to-end at the end furthest from the busbar 2, forming a series branch, and then protected in parallel by only one second bypass diode 22. Compared to the traditional scheme where each small cell or every two small cells in a quarter-cell module is independently equipped with a bypass diode, this design directly reduces the number of bypass diodes (e.g., from 2 to 1). This not only reduces the cost of the diodes themselves but also reduces static power loss caused by reverse leakage current of the diodes, thereby increasing the effective output power of the photovoltaic module under the same illumination conditions. At the same time, the reduction in the number of diodes also means that fewer electrical nodes need to be handled inside the module, reducing the number of potential failure points.

[0068] Furthermore, this structure effectively reduces the number of jumpers 3 used, optimizing the strength and process yield of the photovoltaic module. In Embodiment 2, the two second cell units 20 are directly connected in series, eliminating the need to converge the output terminals of the two independent diodes to the busbar 2 via jumpers 3 as in Embodiment 1, thus reducing the total length of the solder ribbon and jumpers 3, as well as the number of solder points. The reduction in the number of jumpers 3 directly reduces the risk of microcracks in the cell due to uneven stress on the solder ribbon during lamination, and also reduces shading losses that may be caused by excessively long solder ribbons. In addition, the simplified wiring structure makes the back of the module look cleaner and more compact, improving the overall aesthetics of the product.

[0069] In Embodiment 3 of this application, as Figure 3 As shown, the first battery unit 10 is located between two second battery units 20; the first battery unit 10 is connected in parallel with a first bypass diode 12, and the second battery unit 20 is connected in parallel with a second bypass diode 22. The two second bypass diodes 22 are respectively connected to the bus bar 2 through jumpers 3.

[0070] This embodiment employs a symmetrical layout with a large battery in the center and smaller batteries on either side. Specifically, in Figure 3 In the structure shown, the first battery cell 10 (large battery) is located in the middle, with two second battery cells 20 (small batteries) on either side. This arrangement breaks the monotony of traditional single-cell arrangements in photovoltaic modules, creating a unique appearance with visual depth. Furthermore, this symmetrical structure not only enhances the aesthetics of the photovoltaic module and meets the demands of customized appearances, but also provides more uniform physical stress, helping to disperse stress during the lamination process and reducing the risk of microcracks in the cells due to uneven stress. This, in turn, improves the overall strength and long-term reliability of the module.

[0071] In terms of electrical performance, it simultaneously achieves excellent current matching and independent bypass protection. The first battery cell 10 and two second battery cells 20 are electrically connected in parallel (or through a series-parallel combination). The first battery cell 10 is connected in parallel with a first bypass diode 12, and each of the two second battery cells 20 is connected in parallel with a second bypass diode 22, which are then connected to the busbar 2 via jumpers 3. This independently connected bypass diode configuration ensures that each battery cell or battery pack receives immediate protection in the event of partial shading or a fault, preventing the entire branch from shutting down due to the failure of a single cell. Furthermore, since the area of ​​the first battery cell 10 is twice that of the second battery cell 20, and its electrical parameters are adapted, this layout ensures current balance between the parallel branches, reducing problems caused by current mismatch and thus contributing to improving the overall output power of the photovoltaic module.

[0072] Furthermore, this embodiment achieves a good balance between manufacturing process flexibility and cost control. Although the number of jumpers 3 increases compared to Embodiment 2, its structure still maintains a high degree of integration compared to a completely independent four-piece design. The centrally located first battery cell 10 makes the arrangement of the solder strips and jumpers 3 more regular, facilitating automated equipment operation and improving production efficiency.

[0073] In Embodiment 4 of this application, as Figure 4 As shown, the first battery unit 10 is located between two second battery units 20; the first battery unit 10 includes two first battery strings 13 arranged in parallel, and the two ends of each first battery string 13 are connected in parallel with the corresponding second battery unit 20. The second battery unit 20 is connected in parallel with a second bypass diode 22, and the bypass diode is connected to the bus bar 2 through the first battery string 13.

[0074] In this embodiment, the first battery cell 10 (large battery, such as a half cell) is subdivided into two parallel first battery strings 13. This design is equivalent to paralleling and shunting the current carrying capacity of the large battery. Compared to a single large battery string directly bearing all the current, the dual-string parallel structure effectively increases the conductive cross-sectional area and reduces the ohmic resistance loss of the main circuit. At the same time, this layout makes the path of current converging from the two second battery cells 20 (small batteries) to the busbar 2 more symmetrical and shorter, reducing the voltage drop and shading caused by long jumpers 3, thereby improving the overall conversion efficiency of the photovoltaic module.

[0075] Furthermore, this design significantly simplifies the connection logic of the bypass diodes, reducing process complexity and potential failure points. In this embodiment, the second battery cell 20 is connected in parallel with a second bypass diode 22. These diodes are not directly connected to the busbar 2, but are connected to the busbar 2 through the first battery string 13. This allows the first battery string 13 to not only perform the power generation task but also to perform part of the interconnection and conduction function, reducing the number of independent jumpers 3 and additional connection points, making the wiring of the photovoltaic module simpler. In addition, since the bypass diodes are connected to the busbar 2 through the battery string, when the second battery cell 20 fails, the current can bypass through the first battery string 13, making the protection mechanism more reliable and avoiding the contact problems that may occur due to the individual connection of the diodes.

[0076] In some embodiments, the number of first battery cells 10 is greater than the number of second battery cells 20; there are two first battery cells 10 and one second battery cell 20, and n1 is twice n2.

[0077] For example, since the area of ​​the first cell 10 (e.g., half-cell) is twice that of the second cell 20 (e.g., quarter-cell), i.e., n1 is twice n2, the total current capacity of the two first cell cells 10 connected in parallel matches the equivalent current of the second cell cell 20 connected in series or parallel. This achieves efficient current convergence and stable voltage output, significantly optimizing the electrical performance of the photovoltaic module. Furthermore, this design allows the photovoltaic module to maintain a standard voltage output while increasing the number of first cell cells 10 to enhance the overall current carrying capacity, thus adapting to higher power applications. In addition, the parallel structure of the two first cell cells 10 reduces the current density of a single cell, decreasing Joule heat generated by large currents passing through the internal resistance of a single cell, which helps improve the thermal stability of the photovoltaic module and extend its lifespan.

[0078] Furthermore, in this configuration, the two first battery cells 10 can be arranged and soldered as a single module, while the second battery cell 20 serves as an independent supplementary module. This modular design reduces the need for complex jumper wire 3 connections and diode configurations. For example, the two first battery cells 10 can share a bypass diode or be distributed symmetrically, thereby reducing the number of bypass diodes and the total length of jumper wires 3. The reduction in the number of jumper wires 3 not only reduces shading losses and contact resistance but also simplifies the stress distribution during the lamination process, reduces the risk of microcracks in the cells, and improves production yield and module reliability.

[0079] It is evident that by adopting a combination of two large battery units and a second battery unit 20, it is possible to more flexibly address the matching of battery cells of different specifications. This not only improves the comprehensive utilization rate of waste battery cells and reduces waste caused by specification mismatch, but also enables photovoltaic module design to be customized according to different specific requirements for power, appearance or cost, thus meeting the market's different demands for personalized photovoltaic modules.

[0080] In Embodiment 5 of this application, as Figure 5 As shown, the second battery unit 20 is located on the side of one first battery unit 10 away from the other first battery unit 10; the first battery unit 10 is connected in parallel with a first bypass diode 12, and the second battery unit 20 is connected in parallel with a second bypass diode 22, which is connected to the bus bar 2 via a jumper 3.

[0081] In this embodiment, the second battery unit 20 (small battery) is located on one side of the two first battery units 10 (large battery), breaking the traditional symmetrical structural design. This not only provides photovoltaic modules with a variety of appearance options and meets the market's demand for customized and aesthetically pleasing products, but also provides greater flexibility in layout. The positions of the large and small battery units can be flexibly adjusted according to the space constraints or aesthetic preferences of the installation environment, so that the photovoltaic modules can be more perfectly integrated into different application scenarios.

[0082] Furthermore, this design achieves a good balance between electrical protection and power loss, optimizing the power generation efficiency of the photovoltaic module. The first cell unit 10 is connected in parallel with a first bypass diode 12, while the second cell unit 20 is connected in parallel with a second bypass diode 22 and connected to the busbar 2 via jumper 3. This independent bypass protection mechanism ensures that when any cell unit (whether large or small) is partially shaded or malfunctions, the corresponding bypass diode can quickly conduct, preventing the spread of hot spot effects and ensuring the safe operation of the module. Simultaneously, because the number of second cell units 20 is small and they are individually connected, the total length and number of jumpers 3 are relatively controllable, reducing shading and contact resistance losses caused by complex wiring. Compared to a completely symmetrical and complex mixed-cell structure, this asymmetrical layout simplifies some electrical connections while ensuring protection functions, contributing to improved overall module conversion efficiency.

[0083] In Embodiment Six of this application, as Figure 6 As shown, the second battery unit 20 is located between the two first battery units 10; the first battery unit 10 is connected in parallel with a first bypass diode 12, and the second battery unit 20 is connected in parallel with a second bypass diode 22. The second bypass diode 22 is connected to the bus bar 2 via a jumper 3.

[0084] This embodiment achieves a balanced stress distribution and a significant increase in strength within the photovoltaic module through a symmetrical structure. Figure 6 In the layout shown, the second cell unit 20 (a small cell, such as a quarter cell) is placed between two first cell units 10 (large cells, such as half cells), forming a symmetrical arrangement. This structure can more evenly distribute pressure during the lamination process, effectively reducing the risk of microcracks in the cells caused by edge effects or uneven local stress, especially protecting the relatively fragile second cell unit 20 located in the center. At the same time, the symmetrical layout makes the torque more balanced when the photovoltaic module is subjected to external stress, improving the overall structural stability and weather resistance of the photovoltaic module and extending its service life.

[0085] Furthermore, this design optimizes the reliability of electrical connections and reduces shading losses. Each of the first battery cells 10 is connected in parallel with a first bypass diode 12, while the second battery cell 20, located in the middle, is connected in parallel with a second bypass diode 22 and connected to the busbar 2 via a jumper 3. This layout also makes the bypass diodes more concentrated and organized, facilitating heat dissipation management and reducing the risk of performance degradation or failure due to high temperatures. When the middle second battery cell 20 fails, its corresponding bypass diode quickly conducts, providing a rapid response to the protection mechanism and ensuring the continuous power generation capability of the photovoltaic module under partial shading conditions.

[0086] In some embodiments, one of n1 and n2 is half, and the other of n1 and n2 is one-quarter.

[0087] Half-cell cells (one of n1 or n2 being 1 / 2) have half the internal series resistance compared to full-cell cells, thus significantly reducing losses caused by resistance. Quarter-cell cells (the other of n1 or n2 being 1 / 4) further halve the current, resulting in a higher fill factor for the photovoltaic module under the same illumination conditions. Using these two specifications in combination allows for optimization of local circuit loss matching by leveraging the extremely low current characteristics of quarter-cell cells, while ensuring the photovoltaic module's voltage standards. Especially under partial shading or low illumination conditions, this hybrid structure can more effectively reduce mismatch losses, thereby improving the average power generation efficiency of the photovoltaic module under all weather conditions.

[0088] Furthermore, this combination significantly improves the utilization rate of battery materials and substantially reduces production costs. In photovoltaic production, during the process of cutting full-cell batteries into half-cells or quarter-cells, micro-cracks or damage often occur at the edges, rendering some cells unusable for standard half-cell modules. This embodiment allows these smaller, recut quarter-cell batteries to be mixed and packaged with qualified half-cell batteries, enabling the reuse of cells that might otherwise be discarded or downgraded due to size mismatch. This not only reduces raw material waste but also lowers the per-watt production cost by increasing yield.

[0089] In some embodiments, the photovoltaic module further includes an encapsulating film and a cover plate, wherein the encapsulating film is used to cover the surfaces of the first battery string 11 and the second battery string 21; and the cover plate is used to cover the surfaces of the encapsulating film that are opposite to the surfaces of the first battery string 11 and the second battery string 21.

[0090] The standard laminated encapsulation structure provides environmental protection and safety features for hybrid photovoltaic modules. The encapsulating film (such as EVA or POE film) tightly covers the surfaces of the first cell string 11 and the second cell string 21, which not only serves as electrical insulation to prevent short circuits or leakage between the cells and the external environment, but also maximizes the conversion efficiency of light energy to electrical energy through its high light transmittance and good adhesion.

[0091] Meanwhile, the encapsulating film can buffer external impacts and protect the fragile solar cells from physical damage. The cover plate (usually tempered glass) covers the side of the encapsulating film away from the solar cells, serving as the outermost layer of protection for the photovoltaic module. It has extremely high strength and weather resistance, effectively resisting the onslaught of harsh natural environments such as wind pressure, snow load, and hail, ensuring the structural integrity of the photovoltaic module during long-term outdoor operation.

[0092] Furthermore, this encapsulation structure effectively isolates moisture, oxygen, and corrosive gases, significantly improving the corrosion resistance and lifespan of the photovoltaic modules. The sealed space formed by the encapsulating film and the cover plate blocks the penetration paths of moisture and oxygen, preventing oxidation and corrosion of the cell's metal electrodes (such as silver paste grid lines) and chemical degradation of the cells themselves. Because different specifications of cells may have slight differences in manufacturing processes or aging rates, a good encapsulation environment ensures that all cell units operate under consistent environmental conditions, reducing performance inconsistencies caused by environmental factors and thus maintaining the stability of the overall power output of the photovoltaic modules.

[0093] According to some embodiments of this application, another aspect of this application provides a method for preparing a photovoltaic module, applicable to the photovoltaic modules mentioned above. The preparation method includes:

[0094] Acquire the first battery cell 110 and the second battery cell 210;

[0095] The first battery cell 110 and the second battery cell 210 are connected in series to form at least two first battery strings 11 and at least two second battery strings 21 respectively; and at least two first battery strings 11 are connected in series to form a first battery unit 10 and at least two second battery strings 21 are connected in series to form a second battery unit 20.

[0096] At least one first battery cell 10 and at least two second battery cells 20, or at least two first battery cells 10 and at least one second battery cell 20 are connected in parallel via a busbar 2 to form a battery cell group 1 containing at least three battery cells;

[0097] Bypass diodes are respectively configured for the first battery cell 10 and the second battery cell 20;

[0098] In this configuration, at least one bypass diode of the second battery cell 20 is connected to the busbar 2 via a common jumper 3.

[0099] This fabrication method significantly improves the production efficiency and process consistency of mixed-cell photovoltaic modules. In the fabrication process, the first cell 110 and the second cell 210 are first connected in series to form independent cell strings. These cell strings are then further assembled into first cell units 10 and second cell units 20. This hierarchical assembly method allows for standardized operations for cell strings of different specifications, reducing the layout complexity caused by cell mixing. Subsequently, multiple cell units are connected in parallel via busbars 2. This modular integration method not only simplifies the wiring process before lamination but also facilitates quality control and troubleshooting, ensuring the reliability of electrical connections within each cell unit, thereby improving the yield and production speed of the final product.

[0100] Furthermore, this method effectively reduces material costs and simplifies the backplane wiring structure by optimizing the connection method of the bypass diodes. In the fabrication process, the bypass diodes of at least one second cell unit 20 (small cell unit) are connected to the busbar 2 via a shared jumper 3, rather than being connected independently. This reduces the number of jumpers 3 and solder joints, directly lowering production costs. Simultaneously, the shared jumper 3 design makes the wiring on the back of the photovoltaic module neater and more compact, reducing the risk of lamination bubbles or microcracks caused by interlaced wiring. This simplified wiring process not only reduces manufacturing costs but also improves the aesthetic appearance of the module, meeting the requirements for product refinement, and facilitating subsequent automated testing and installation maintenance.

[0101] In some embodiments, the preparation method further includes:

[0102] The entire waste battery cell is cut once, and the waste part is removed to obtain the first battery cell 110 with n1 segments;

[0103] The edge defects of the first battery cell 110 are cut a second time to obtain the second battery cell 210 with n2 segments;

[0104] The size of the second battery cell 210 is half the size of the first battery cell 110.

[0105] By employing a secondary cutting process, the maximum utilization rate of battery raw materials is achieved, significantly reducing production losses and raw material costs. In traditional production, when a full-cell battery is cut into half-cells, micro-cracks or damage at the edges often result in some cells being deemed defective or downgraded, leading to resource waste. By secondary cutting the defective portions at the edges of the first cell 110 (e.g., half-cell) into a second cell 210 (e.g., quarter-cell), materials that might otherwise be discarded are reintroduced into the production process. This manufacturing process not only improves the effective yield of a single full-cell battery but also reduces manufacturing costs at the source by internally utilizing defective products.

[0106] Furthermore, this process, through strict dimensional control (the second cell 210 is half the size of the first cell 110), ensures the matching and stability of the internal electrical parameters of the hybrid module. Since the second cell 210 is precisely cut from the first cell 110, its size, thickness, and material properties are highly consistent with the first cell 110, with only a definite multiple relationship in area. This design guarantees a high correlation between the two in key electrical parameters such as photoelectric conversion efficiency and dark current characteristics, making it easier to achieve current and voltage balance in series or parallel circuits. This not only reduces power loss caused by excessive differences in cell dimensions but also simplifies the electrical matching difficulty in photovoltaic module design, improving the uniformity and reliability of the overall module output performance.

[0107] Those skilled in the art will understand that the above embodiments are specific examples of implementing this application, and in practical applications, various changes in form and detail can be made without departing from the spirit and scope of this application. Any person skilled in the art can make various alterations and modifications without departing from the spirit and scope of this application; therefore, the scope of protection of this application should be determined by the scope defined in the claims.

Claims

1. A photovoltaic module, characterized in that, It includes at least one battery cell group, the battery cell group including at least three battery cells connected in parallel by a busbar, the at least three battery cells including at least one first battery cell and at least two second battery cells, or at least two first battery cells and at least one second battery cell; The first battery unit includes at least two first battery strings connected in series, each first battery string including one or more first battery cells connected in series; the second battery unit includes at least two second battery strings connected in series, each second battery string including one or more second battery cells connected in series. The number of battery cells is odd; the first battery cell is an n1-piece cut from a whole battery cell, and the second battery cell is an n2-piece cut from a whole battery cell, with n1 and n2 being a multiple of each other.

2. The photovoltaic module according to claim 1, characterized in that, The first battery unit is one, the second battery unit is two, and n1 is twice n2.

3. The photovoltaic module according to claim 2, characterized in that, The first battery cell is located on the side of one of the second battery cells away from the other second battery cell, and the first battery cell is connected in parallel with a first bypass diode; The second battery cell is connected in parallel with a second bypass diode, and the two second bypass diodes are connected to the busbar through the same jumper; or, the ends of the two second battery cells away from the busbar are connected together, and the two second battery cells are simultaneously connected in parallel with second bypass diodes.

4. The photovoltaic module according to claim 2, characterized in that, The first battery cell is located between the two second battery cells; the first battery cell is connected in parallel with a first bypass diode, and the second battery cells are connected in parallel with a second bypass diode, and the two second bypass diodes are respectively connected to the bus bar via jumpers.

5. The photovoltaic module according to claim 2, characterized in that, The first battery unit is located between two second battery units; the first battery unit includes two first battery strings arranged in parallel, the two ends of each first battery string are connected in parallel to the corresponding second battery unit, and the second battery unit is connected in parallel to a second bypass diode, which is connected to the bus bar through the first battery string.

6. The photovoltaic module according to claim 1, characterized in that, The first battery unit consists of two units, the second battery unit consists of one unit, and n1 is twice n2.

7. The photovoltaic module according to claim 6, characterized in that, The second battery cell is located on the side of one of the first battery cells away from the other; the first battery cell is connected in parallel with a first bypass diode, and the second battery cell is connected in parallel with a second bypass diode, which is connected to the busbar via a jumper.

8. The photovoltaic module according to claim 6, characterized in that, The second battery cell is located between the two first battery cells; the first battery cell is connected in parallel with a first bypass diode, and the second battery cell is connected in parallel with a second bypass diode, which is connected to the busbar via a jumper.

9. The photovoltaic module according to claim 1, characterized in that, One of n1 and n2 is one-half, and the other of n1 and n2 is one-quarter.

10. The photovoltaic module according to claim 1, characterized in that, The photovoltaic module also includes: An encapsulating film is used to cover the surfaces of the first battery string and the second battery string; A cover plate is used to cover the surface of the encapsulating film that is away from the first battery string and the second battery string.

11. A method for preparing a photovoltaic module, applicable to the photovoltaic module according to any one of claims 1 to 10, characterized in that, The preparation method includes: Acquire the first and second battery cells; The first battery cell and the second battery cell are connected in series to form at least two first battery strings and at least two second battery strings, respectively; and the at least two first battery strings are connected in series to form a first battery unit and the at least two second battery strings are connected in series to form a second battery unit. At least one first battery cell and at least two second battery cells, or at least two first battery cells and at least one second battery cell, are connected in parallel via a busbar to form a battery cell group containing at least three battery cells; Bypass diodes are configured for the first battery cell and the second battery cell, respectively; In this configuration, at least one bypass diode of the second battery cell is connected to the busbar via a common jumper.

12. The method for preparing a photovoltaic module according to claim 11, characterized in that, The preparation method further includes: The entire waste battery cell is cut once, and the discarded part is removed to obtain the first battery cell with n1 segments; The edge defects of the first battery cell are cut a second time to obtain the second battery cell with n2 segments; The size of the second battery cell is half the size of the first battery cell.

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