Back contact battery assembly and photovoltaic system

Abstract

The utility model is suitable for the technical field of solar cells, and provides a back contact cell module and a photovoltaic system. The back contact battery assembly includes: a first bus bar and a second bus bar respectively connected to a first interface and a second interface of the junction box; each of the adjacent first string and second string comprises a plurality of battery pieces connected in series, the first string comprises a first end battery and a first end welding strip, and the first end welding strip is connected with the first end battery and the first bus bar and comprises a first welding strip closest to the second bus bar; the second string comprises a second end battery and a second end welding strip, the second end welding strip is connected with the second end battery and the second bus bar, and the second end welding strip comprises a second welding strip closest to the first bus bar; the first solder strip is the outermost solder strip in the solder strips connected with the first end battery; the second solder strip is a solder strip adjacent to the outermost solder strip in the solder strips connected with the second end battery; the back contact battery assembly satisfies the following formula: D < E < 2D.

Description

Technical Field

[0001] This application belongs to the field of solar cell technology, and particularly relates to a back-contact battery module and a photovoltaic system. Background Technology

[0002] In related technologies, a busbar is typically used to connect the junction box to the battery array of the back-contact battery assembly. However, the space within the back-contact battery assembly is limited, resulting in insufficient space to accommodate the junction box and inadequate operating space for its installation.

[0003] Therefore, how to provide sufficient space for the junction box in the back contact battery assembly has become an urgent problem to be solved. Utility Model Content

[0004] This application provides a back-contact battery module and a photovoltaic system, aiming to solve the problem of how to provide sufficient space for the junction box in the back-contact battery module.

[0005] The back contact battery assembly provided in this application includes:

[0006] A back-contact battery assembly, characterized in that it comprises:

[0007] The first busbar and the second busbar are respectively connected to the first interface and the second interface of the junction box;

[0008] The first and second adjacent strings each include a number of battery cells connected in series. The first string includes a first end battery and a first end solder strip. The first end solder strip connects the first end battery to the first busbar and includes the first solder strip closest to the second busbar. The second string includes a second end battery and a second end solder strip. The second end solder strip connects the second end battery to the second busbar and includes the second solder strip closest to the first busbar.

[0009] The first solder strip is the outermost solder strip among the solder strips connected to the first end battery; the second solder strip is the solder strip adjacent to the outermost solder strip among the solder strips connected to the second end battery.

[0010] The back contact battery assembly satisfies the following formula: D < E < 2D;

[0011] Where D is the minimum distance between two adjacent third solder strips, the third solder strip is the solder strip connected to the first end battery excluding the first solder strip and the solder strip adjacent to the first solder strip, and E is the distance between the first solder strip and the second solder strip.

[0012] Specifically, D is 3mm-10mm.

[0013] Specifically, E is greater than 3mm and less than 20mm.

[0014] Specifically, the back contact battery assembly satisfies the following formula: D1+D2+S1>B+L02-L01;

[0015] Wherein, D1 is the distance from the first solder strip to the corresponding edge of the first end battery, D2 is the distance from the second solder strip to the corresponding edge of the second end battery, S1 is the distance between the first end battery and the second end battery, B is the distance from the first interface to the second interface, L01 is the distance from the end of the second busbar away from the junction box to the bending start point of the second busbar in the length direction of the busbar, and L02 is the distance from the end of the second busbar away from the junction box to the second interface in the length direction of the busbar.

[0016] Specifically, the back contact battery assembly satisfies the following formula: D1+D2+S1>B+L02-L01+L12-L11;

[0017] Wherein, L11 is the distance from the end of the first busbar away from the junction box to the bending point of the first busbar in the length direction of the busbar, and L12 is the distance from the end of the first busbar away from the junction box to the first interface in the length direction of the busbar.

[0018] Specifically, the back contact battery assembly includes a third string located on the side of the second string away from the first string. The third string includes a third end battery and a third end solder strip. The third end battery is located on the side of the second end battery away from the first end battery. The third end solder strip connects the third end battery to the second busbar. The back contact battery assembly satisfies the following formula: S1 > S2.

[0019] Wherein, S1 is the distance between the first end battery and the second end battery, and S2 is the distance between the third end battery and the second end battery.

[0020] Specifically, the first end battery includes a third solder strip, which is the solder strip connected to the first end battery other than the first solder strip and the solder strip adjacent to the first solder strip. The back contact battery assembly satisfies the following formula:

[0021] D1 > D;

[0022] Wherein, D1 is the distance from the first solder strip to the corresponding edge of the first end battery.

[0023] Specifically, the first end battery includes a third solder strip, which is the solder strip connected to the first end battery other than the first solder strip and the solder strip adjacent to the first solder strip. The back contact battery assembly satisfies the following formula:

[0024] D1+D2+S1>3D;

[0025] Wherein, D1 is the distance from the first solder strip to the corresponding edge of the first end battery, D2 is the distance from the second solder strip to the corresponding edge of the second end battery, and S1 is the distance between the first end battery and the second end battery.

[0026] Specifically, the back contact battery assembly includes a first series structure and a second series structure, which are located on both sides of the first busbar, and the second series structure is connected in parallel with the first series structure.

[0027] The back contact battery assembly includes parallel busbars, which include a first busbar and a second busbar;

[0028] The first series structure includes a plurality of first battery strings connected in series and arranged along a first direction. The first battery string includes a first string and a second string. At least one first battery string includes a first string end battery and a first string end solder strip. The first string end battery includes a first end battery and a second end battery. The first string end solder strip connects the first string end battery and the parallel bus bar, including the first end solder strip and the second end solder strip.

[0029] The second series structure includes a plurality of second battery strings connected in series and arranged along a first direction, at least one of the second battery strings including a second string terminal battery and a second string terminal solder strip, the second string terminal solder strip connecting the second string terminal battery and the parallel bus bar;

[0030] The first terminal solder strip is staggered from the second terminal solder strip.

[0031] Specifically, the solder strips connected to the first series-terminated battery include a first edge solder strip and a second edge solder strip, the first edge solder strip and the second edge solder strip being closest to the two edges of the first series-terminated battery in the length direction of the parallel busbar; the solder strips connected to the second series-terminated battery include a third edge solder strip and a fourth edge solder strip, the third edge solder strip and the fourth edge solder strip being closest to the two edges of the second series-terminated battery in the length direction of the parallel busbar;

[0032] The back contact battery assembly satisfies the following formula:

[0033] 0 < w0 ≤ |w1 - w2|;

[0034] 0 < w0 ≤ |w3 - w4|;

[0035] Wherein, w0 is the minimum distance between the first and second serial terminal solder strips; w1 is the distance between the first edge solder strip and the corresponding edge of the first serial terminal battery; w2 is the distance between the second edge solder strip and the corresponding edge of the first serial terminal battery; w3 is the distance between the third edge solder strip and the corresponding edge of the second serial terminal battery; and w4 is the distance between the fourth edge solder strip and the corresponding edge of the second serial terminal battery.

[0036] Specifically, the back contact battery assembly satisfies the following formula:

[0037] 0.25×|w1-w2|≤w0;

[0038] 0.25×|w3-w4|≤w0.

[0039] The photovoltaic system provided in this application includes the back-contact battery module of any of the above.

[0040] The back-contact battery module and photovoltaic system of this application embodiment have sufficient space for setting up a junction box, since the adjacent first and second solder strips connected to two adjacent busbars are respectively the outermost solder strip and the second-second edge solder strip, and the distance between the first and second solder strips is between 1 and 2 times the minimum value of the distance between two adjacent third solder strips. This facilitates the installation of the junction box between the adjacent first and second busbars, which is beneficial to improving the production efficiency of the back-contact battery module. Attached Figure Description

[0041] Figure 1 This is a partial structural schematic diagram of a back contact battery assembly according to an embodiment of this application;

[0042] Figure 2 This is a schematic diagram of the structure of a back contact battery assembly according to an embodiment of this application;

[0043] Figure 3 This is a partial structural schematic diagram of a back contact battery assembly according to an embodiment of this application;

[0044] Figure 4 This is a partial structural schematic diagram of a back contact battery assembly according to an embodiment of this application;

[0045] Figure 5 This is a partial structural schematic diagram of a back contact battery assembly according to an embodiment of this application;

[0046] Figure 6 This is a partial structural schematic diagram of a back contact battery assembly according to an embodiment of this application;

[0047] Figure 7 This is a partial structural schematic diagram of a back contact battery assembly according to an embodiment of this application;

[0048] Explanation of key component symbols:

[0049] Back contact battery assembly 100, parallel busbar 10, first busbar 11, first main body 111, first bent portion 112, second busbar 12, second main body 121, second bent portion 122, junction box 20, first interface 21, second interface 22, first battery string 30, first string end battery 301, first string end solder strip 302, first edge solder strip 303, second edge solder strip 304, first string 31, first end battery 311, first end solder strip 3 12. First welding strip 3120, first non-end welding strip 313, third welding strip 314, second string 32, second end battery 321, second end welding strip 322, second welding strip 3220, second non-end welding strip 323, third string 33, third end battery 331, third end welding strip 332, third non-end welding strip 333, second battery string 40, second string end battery 401, second string end welding strip 402, third edge welding strip 403, fourth edge welding strip 404. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. Furthermore, it should be understood that the specific embodiments described herein are merely for explaining this application and are not intended to limit this application.

[0051] In the description of this application, it should be understood that the terms "length", "width", "upper", "lower", "left", "right", "horizontal", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and 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 of this application.

[0052] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0053] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" 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, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0054] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0055] The following disclosure provides numerous different embodiments or examples for implementing various structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, various specific examples of processes and materials are provided in this application, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0056] Please see Figure 1 and Figure 2 The back contact battery assembly 100 of this application embodiment includes:

[0057] The first busbar 11 and the second busbar 12 are respectively connected to the first interface 21 and the second interface 22 of the junction box 20;

[0058] The adjacent first string 31 and second string 32 each include a number of battery cells connected in series. The first string 31 includes a first end battery 311 and a first end solder strip 312. The first end solder strip 312 connects the first end battery 311 and the first busbar 11, including the first solder strip 3120 closest to the second busbar 12. The second string 32 includes a second end battery 321 and a second end solder strip 322. The second end solder strip 322 connects the second end battery 321 and the second busbar 12, including the second solder strip 3220 closest to the first busbar 11.

[0059] The first solder strip 3120 is the outermost solder strip among the solder strips connected to the first end battery 311; the second solder strip 3220 is the solder strip adjacent to the outermost solder strip among the solder strips connected to the second end battery 321.

[0060] The back contact battery assembly 100 satisfies the following formula: D1+D2+S1>B+L02-L01;

[0061] Wherein, D1 is the distance from the first solder strip 3120 to the corresponding edge of the first end battery 311, D2 is the distance from the second solder strip 3220 to the corresponding edge of the second end battery 321, S1 is the distance between the first end battery 311 and the second end battery 321, B is the distance from the first interface 21 to the second interface 22, L01 is the distance from the end of the second busbar 12 away from the junction box 20 to the bending point of the second busbar 12 in the length direction of the second busbar 12, and L02 is the distance from the end of the second busbar 12 away from the junction box 20 to the second interface 22 in the length direction of the busbar.

[0062] In the back contact battery module 100 of this application embodiment, since the adjacent solder strips connected to the two adjacent busbars are the outermost solder strip and the second edge solder strip respectively, and the sum of the distances to the corresponding battery edges plus the distance between the two batteries is greater than the sum of the distance between the two interfaces of the junction box 20 and the bending distance of the second busbar 12, sufficient space can be provided for setting the junction box 20, which is convenient for installing the junction box 20 between the first busbar 11 and the second busbar 12, which is beneficial to improving the production efficiency of photovoltaic modules.

[0063] Specifically, the first busbar 11 is connected to the first interface 21 of the junction box 20. The second busbar 12 is connected to the second interface 22 of the junction box 20. One of the first interface 21 and the second interface 22 of the junction box 20 is a positive interface, and the other is a negative interface.

[0064] Specifically, the back-contact battery assembly 100 includes a first series structure 101 and a second series structure 102, which are connected in parallel and include a plurality of battery strings arranged along a first direction. Each battery string includes a plurality of battery cells arranged along a second direction, which intersects the first direction. The battery strings in the first series structure 101 are first battery strings 30, including a first string 31, a second string 32, and a third string 33. The battery strings in the second series structure 102 are second battery strings 40.

[0065] Specifically, the first string 31 includes a number of solar cells connected in series. For example, the first string 31 may include 2, 3, 4, or other numbers of solar cells. Similarly, the second string 32 includes a number of solar cells connected in series. For example, the second string 32 may include 2, 3, 4, or other numbers of solar cells. The number of solar cells in the first string 31 and the second string 32 is not limited here.

[0066] Specifically, the solar cells may include solar cells with back contact main grids or solar cells without back contact main grids; the specific form of the solar cells is not limited here.

[0067] Specifically, the first string 31 includes a first end battery 311, a first end solder strip 312, and a first non-end solder strip 313. The first end solder strip 312 connects the first end battery 311 to the first busbar 11. The first non-end solder strip 313 connects the first end battery 311 to the battery cell adjacent to the first end battery 311. One of the first end solder strip 312 and the first non-end solder strip 313 is electrically connected to the positive grid line of the first end battery 311, and the other is electrically connected to the negative grid line of the first end battery 311.

[0068] Furthermore, the first end solder strip 312 includes a first solder strip 3120 closest to the second busbar 12. In other words, there are multiple first end solder strips 312, and the first end solder strip 312 closest to the second busbar 12 is the first solder strip 3120.

[0069] Furthermore, the first solder strip 3120 is the outermost solder strip among the solder strips connected to the first end battery 311. In other words, the first solder strip 3120 is the solder strip closest to the second busbar 12 and located at the outermost edge among the first end solder strip 312 and the first non-end solder strip 313. That is, there is no first non-end solder strip 313 between the first solder strip 3120 and the second busbar 12.

[0070] Specifically, the second string 32 includes a second end battery 321, a second end solder strip 322, and a second non-end solder strip 323. The second end solder strip 322 connects the second end battery 321 to the second busbar 12. The second non-end solder strip 323 connects the second end battery 321 to the battery cell adjacent to the second end battery 321. One of the second end solder strip 322 and the second non-end solder strip 323 is electrically connected to the positive grid line of the second end battery 321, and the other is electrically connected to the negative grid line of the second end battery 321.

[0071] Furthermore, the second end solder strip 322 includes a second solder strip 3220 that is closest to the first busbar 11. In other words, there are multiple second end solder strips 322, and the second end solder strip 322 that is closest to the first busbar 11 is the second solder strip 3220.

[0072] Furthermore, the second solder strip 3220 is the solder strip adjacent to the outermost solder strip among the solder strips connecting the second end battery 321. In other words, the second solder strip 3220 is the solder strip closest to the first busbar 11 and adjacent to the outermost solder strip among the second end solder strip 322 and the second non-end solder strip 323. That is, there is a second non-end solder strip 323 between the second solder strip 3220 and the first busbar 11, and this second non-end solder strip 323 is the solder strip located at the outermost edge and closest to the first busbar 11 among the solder strips connecting the second end battery 321.

[0073] Specifically, the back contact battery assembly 100 satisfies the following formula: D1+D2+S1>B+L02-L01.

[0074] Wherein, D1 is the distance from the first solder strip 3120 to the corresponding edge of the first end battery 311. Note that "corresponding edge" here refers to the edge of the first end battery 311 that is closer to the first solder strip 3120 among the two edges in the first direction. The "distance" here refers to the distance in the first direction. That is, D1 is the distance in the first direction from the first solder strip 3120 to the edge of the first end battery 311 that is closer to the first solder strip 3120 among the two edges in the first direction.

[0075] Wherein, D2 is the distance from the second solder strip 3220 to the corresponding edge of the second end battery 321. Note that "corresponding edge" here refers to the edge of the second end battery 321 that is closer to the second solder strip 3220 among the two edges in the first direction. The "distance" here refers to the distance in the first direction. That is, D2 is the distance in the first direction from the second solder strip 3220 to the edge of the second end battery 321 that is closer to the second solder strip 3220 among the two edges in the first direction.

[0076] Wherein, S1 is the distance between the first end battery 311 and the second end battery 321. Please note that the "distance" here refers to the distance in the first direction. That is, S1 is the distance between the first end battery 311 and the second end battery 321 in the first direction.

[0077] Where B represents the distance from the first interface 21 to the second interface 22. Note that B can be the distance between the center point of the first interface 21 and the center point of the second interface 22. B can also be the distance between the edge of the first interface 21 closest to the second interface 22 and the edge of the second interface 22 closest to the first interface 21, such as... Figure 1 As shown.

[0078] Wherein, L01 is the distance along the length of the second busbar 12 from the end of the second busbar 12 away from the junction box 20 to the bending start point of the second busbar 12. It can be understood that, to connect to the junction box 20, the end of the second busbar 12 near the junction box 20 bends. The "bending start point" refers to the starting point where the second busbar 12 begins to bend. The "bending start point" can be the connection point between the second busbar 12 and the second solder strip 3220. The "bending start point" can also be the point between the connection point of the second busbar 12 and the second solder strip 3220 and the end of the second busbar 12 near the junction box 20. In one example, the second busbar 12 extends along a first direction, which is also the length direction of the second busbar 12. In other words, L01 is the distance along the first direction from the end of the second busbar 12 away from the junction box 20 to the bending start point of the second busbar 12.

[0079] Wherein, L02 is the distance along the length of the second busbar 12 from the end of the second busbar 12 away from the junction box 20 to the second interface 22. In one example, the second busbar 12 extends along a first direction, which is also the length direction of the second busbar 12. In other words, L02 is the distance along the first direction from the end of the second busbar 12 away from the junction box 20 to the second interface 22.

[0080] Specifically, the value of L02-L01 is the bending distance L0 of the second busbar 12. That is, L0 = L02 - L01. It can be understood that L0 can be 0, such as... Figure 3 As shown; L0 can be a positive number, such as Figure 4 As shown; L0 can be negative, such as Figure 5 As shown.

[0081] Please see Figure 1In some embodiments, D1 is 2mm-15mm. For example, it is 2mm, 3mm, 5mm, 8mm, 10mm, 12mm, 14mm, or 15mm. This ensures that the distance D1 from the first solder strip 3120 to the corresponding edge of the first end battery 311 is within a suitable range. This avoids the first solder strip 3120 being too close to the corresponding edge of the first end battery 311 due to an excessively small D1, which would cause interference with the junction box 20 near that edge. It also avoids the effect of collecting current from the edge grid lines of the first end battery 311 being poor due to an excessively large D1.

[0082] Specifically, D1 is 4mm-5mm. For example, it can be 4mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, 4.5mm, 4.6mm, 4.7mm, 4.8mm, 4.9mm, or 5mm. This further optimizes the range of the distance D1 between the first solder strip 3120 and the corresponding edge of the first end battery 311, balancing the avoidance of interference with ensuring current conduction, resulting in better overall performance. In one example, D1 is 4.805mm.

[0083] Please note that D1 can be a fixed value within the aforementioned range; or it can fluctuate within the aforementioned range. No limitation is imposed here.

[0084] Please see Figure 1 In some embodiments, D2 is greater than D1, and D2 is 5mm-20mm. For example, it is 5mm, 6mm, 8mm, 10mm, 12mm, 15mm, 17mm, 19mm, or 20mm. This ensures that the distance D2 from the second solder strip 3220 to the corresponding edge of the second end battery 321 is within a suitable range. This avoids the second solder strip 3220 being too close to the corresponding edge of the second end battery 321 due to an excessively small D2, which would cause interference with the junction box 20 near that edge. It also avoids the effect of collecting current from the edge grid lines of the second end battery 321 being poor due to an excessively large D2.

[0085] Specifically, D2 is 10mm-12mm. For example, it can be 10mm, 10.1mm, 10.3mm, 10.5mm, 10.8mm, 11mm, 11.1mm, 11.3mm, 11.5mm, 11.7mm, 11.9mm, or 12mm. This further optimizes the range of the distance D2 between the second solder strip 3220 and the corresponding edge of the second end battery 321, balancing the avoidance of interference with ensuring current conduction, resulting in better overall performance. In one example, D2 is 11.715mm.

[0086] Please note that D2 can be a fixed value within the aforementioned range; or it can fluctuate within the aforementioned range. No limitation is imposed here.

[0087] Please see Figure 1 In some embodiments, S1 is 0.5mm-15mm. For example, it is 0.5mm, 0.8mm, 1mm, 3mm, 5mm, 8mm, 10mm, 12mm, 14mm, or 15mm. This ensures that the distance S1 between the first end battery 311 and the second end battery 321 is within a suitable range. This avoids the first end battery 311 being too close to the second end battery 321 and interfering with the junction box 20 if S1 is too small, and also avoids poor utilization of the internal space of the component and waste of internal space if S1 is too large.

[0088] Specifically, S1 is 1mm-2mm. For example, it can be 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, or 2mm. This further optimizes the distance S1 between the first end battery 311 and the second end battery 321, balancing interference avoidance with improved space utilization, resulting in a better overall effect. In one example, S1 is 1.6mm.

[0089] Please note that S1 can be a fixed value within the aforementioned range; or it can fluctuate within the aforementioned range. No limitation is imposed here.

[0090] Please see Figure 1 In some embodiments, B is 3mm-15mm. For example, it is 3mm, 4mm, 6mm, 8mm, 10mm, 12mm, 14mm, or 15mm. This ensures that the distance B between the first interface 21 and the second interface 22 is within a suitable range. This avoids the situation where B is too small, causing the two interfaces of the junction box 20 to be too close, making it difficult to install the ends of the first busbar 11 and the second busbar 12 into the junction box 20. It also avoids the situation where B is too large, causing the junction box 20 to occupy too much space and wasting internal space of the components.

[0091] Specifically, B is 4.5mm-5.5mm. For example, 4.5mm, 4.6mm, 4.7mm, 4.8mm, 4.9mm, 5mm, 5.1mm, 5.2mm, 5.3mm, 5.4mm, and 5.5mm. This balances the installation of the busbar and junction box with space utilization, resulting in a better overall effect. In one example, B is 5.05mm.

[0092] Please note that B can be a fixed value within the aforementioned range; or it can fluctuate within the aforementioned range. No limitation is imposed here.

[0093] Please see Figure 1In some embodiments, the values ​​of L02-L01 are -25mm to 25mm. For example, they are -25mm, -20mm, -15mm, -10mm, -5mm, 0mm, 5mm, 10mm, 15mm, 20mm, and 25mm. This ensures that the values ​​of L02-L01 are within a suitable range. This avoids the second busbar 12 bending too far in the reverse direction due to an excessively small difference, which could cause interference with the junction box 20 or the first busbar 11. It also avoids the second busbar 12 bending too far in the forward direction due to an excessively large difference, which could waste space within the component.

[0094] Preferably, the values ​​of L02-L01 are 4mm-25mm. For example, 4mm, 5mm, 8mm, 10mm, 12mm, 15mm, 18mm, 20mm, and 25mm. This further optimizes the range of values ​​for L02-L01, taking into account both the coordination of the second busbar 12 with other components and space saving, resulting in a better overall effect.

[0095] Please see Figure 1 , Figure 3 , Figure 4 and Figure 5 In some embodiments, the back contact battery assembly 100 satisfies the following formula: D1+D2+S1>B+L02-L01+L12-L11;

[0096] Wherein, L11 is the distance from the end of the first busbar 11 away from the junction box 20 to the bending point of the first busbar 11 in the length direction of the second busbar 12, and L12 is the distance from the end of the first busbar 11 away from the junction box 20 to the first interface 21 in the length direction of the busbar.

[0097] Thus, the sum of the distances from the first solder strip 3120 and the second solder strip 3220 to the corresponding battery edge, plus the distance between the two batteries, is greater than the sum of the distance between the two interfaces of the junction box 20, the bending distance of the first busbar 11, and the bending distance of the second busbar 12. Therefore, more space can be provided for the junction box 20, making it easier to install the junction box 20 between the first busbar 11 and the second busbar 12, which is beneficial to improving the production efficiency of photovoltaic modules.

[0098] Specifically, L11 is the distance along the length of the first busbar 11 from the end of the first busbar 11 away from the junction box 20 to the bending point of the first busbar 11. It can be understood that the first busbar 11 bends at the end closest to the junction box 20 to connect to it. The "bending point" refers to the starting point where the first busbar 11 begins to bend. The "bending point" can be the connection point between the first busbar 11 and the first solder strip 3120. Alternatively, the "bending point" can be the point between the connection point of the first busbar 11 and the first solder strip 3120 and the end of the first busbar 11 closest to the junction box 20. In one example, the first busbar 11 extends along a first direction, which is also the length direction of the first busbar 11. In other words, L11 is the distance along the first direction from the end of the first busbar 11 away from the junction box 20 to the bending point of the first busbar 11.

[0099] Specifically, L12 is the distance along the length of the first busbar 11 from the end of the first busbar 11 away from the junction box 20 to the first interface 21. In one example, the first busbar 11 extends along a first direction, which is also the length direction of the first busbar 11. In other words, L12 is the distance along the first direction from the end of the first busbar 11 away from the junction box 20 to the first interface 21.

[0100] In some embodiments, the values ​​of L12-L11 are -15mm to 15mm. For example, they are -15mm, -12mm, -10mm, -8mm, -5mm, -2mm, 0mm, 2mm, 5mm, 8mm, 10mm, 12mm, and 15mm. This ensures that the values ​​of L12-L11 are within a suitable range. This avoids the first busbar 11 bending too far in the reverse direction due to an excessively small difference, which could cause interference with the junction box 20 or the second busbar 12. It also avoids the first busbar 11 bending too far in the forward direction due to an excessively large difference, which could waste space within the component.

[0101] Preferably, the values ​​of L12-L11 are 3mm-15mm. For example, 3mm, 4mm, 6mm, 8mm, 10mm, 11mm, 12mm, and 15mm. This further optimizes the range of values ​​for L12-L11, taking into account both the coordination of the first busbar 11 with other components and space saving, resulting in a better overall effect.

[0102] Please see Figure 1 and Figure 6In some embodiments, the back contact battery assembly 100 includes a third string 33 located on the side of the second string 32 away from the first string 31. The third string 33 includes a third end battery 331 and a third end solder strip 332. The third end battery 331 is located on the side of the second end battery 321 away from the first end battery 311. The third end solder strip 332 connects the third end battery 331 to the second busbar 12. The back contact battery assembly 100 satisfies the following formula: S1 > S2; where S2 is the distance between the third end battery 331 and the second end battery 321.

[0103] Thus, the distance S1 between the second end battery 321 and the first end battery 311 is greater than the distance S2 between the second end battery 321 and the third end battery 331. The larger space between the second end battery 321 and the first end battery 311 can be used to place the junction box 20. At the same time, the smaller distance between the second end battery 321 and the third end battery 331 can save space within the component.

[0104] Specifically, the third string 33 includes several solar cells connected in series. For example, the third string 33 may include 2, 3, 4, or other numbers of solar cells. The number of solar cells in the third string 33 is not limited here.

[0105] Specifically, the solar cells may include solar cells with back contact main grids or solar cells without back contact main grids; the specific form of the solar cells is not limited here.

[0106] Specifically, the third string 33 includes a third end battery 331, a third end solder strip 332, and a third non-end solder strip 333. The third end solder strip 332 connects the third end battery 331 to the second busbar 12. The third non-end solder strip 333 connects the third end battery 331 to the battery cell adjacent to the third end battery 331. One of the third end solder strip 332 and the third non-end solder strip 333 is electrically connected to the positive grid line of the third end battery 331, and the other is electrically connected to the negative grid line of the third end battery 331.

[0107] Please see Figure 1 and Figure 6 In some embodiments, S2 is 0.5mm-15mm. For example, it is 0.5mm, 0.8mm, 1mm, 3mm, 5mm, 10mm, 12mm, or 15mm. This ensures that the distance S2 between the second end battery 321 and the third end battery 331 is within a suitable range. This avoids the second end battery 321 being too close to the third end battery 331 due to an excessively small distance, which could easily lead to electrical contact. It also avoids the poor utilization of internal space in the module and waste of internal space due to an excessively large distance.

[0108] Specifically, S2 is 1mm-2mm. For example, it can be 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, or 2mm. This further optimizes the spacing S2 between the second-end battery 321 and the third-end battery 331, balancing the avoidance of electrical contact with improved space utilization, resulting in better overall performance. In one example, S2 is 1.5mm.

[0109] Please note that S2 can be a fixed value within the aforementioned range; or it can fluctuate within the aforementioned range. No limitation is imposed here.

[0110] Please see Figure 1 , Figure 3 , Figure 4 and Figure 5 In some embodiments, the first busbar 11 includes a first main body 111 and a first bend 112, the first bend 112 bends from the first main body 111 and connects to the first interface 21; the second busbar 12 includes a second main body 121 and a second bend 122, the second bend 122 bends from the second main body 121 and connects to the second interface 22; the minimum distance d between the first main body 111 and the second main body 121 is 5mm-15mm, for example, 5mm, 8mm, 10mm, 12mm, 14mm, or 15mm.

[0111] In this way, the minimum distance between the first main body 111 and the second main body 121 is within a suitable range, which can avoid the difficulty in installing the junction box 20 or interference with the junction box 20 caused by the minimum distance being too small, and can also avoid the waste of space caused by the minimum distance being too large.

[0112] Preferably, the minimum distance d between the first main body portion 111 and the second main body portion 121 is 7mm-9mm. For example, it is 7mm, 7.5mm, 8mm, 8.5mm, or 9mm. In this way, the minimum distance between the first main body portion 111 and the second main body portion 121 is further optimized, which takes into account both the installation of the junction box 20 and space saving, resulting in a better overall effect.

[0113] Specifically, the first busbar 11 is divided into a first main body 111 and a first bent portion 112, with the bend starting point as the boundary. In other words, the beginning of the first bent portion 112 is the bend starting point in the first busbar 11, and the end is the end that connects to the first interface 21.

[0114] Similarly, the second busbar 12 is divided into a second main body 121 and a second bent portion 122, with the bend starting point as the boundary. In other words, the beginning of the bend in the second busbar 12 is the bend starting point, and the end is the end that connects to the second interface 22.

[0115] Please note that in Figure 3 , Figure 4 and Figure 5 In the diagram, one end of d does not overlap with one end of L01. This is because the first busbar 11 has thickness, resulting in different bending starting points on both sides. Since d is the minimum distance between the first main body 111 and the second main body 121, the endpoint selected at the second main body 121 in the diagram is the bending starting point closer to the first main body 111. And since L01 is the distance from the end of the second busbar 12 away from the junction box 20 to the bending starting point of the second busbar 12 along the length of the second busbar 12, the selected endpoint is the bending starting point closer to the end of the second busbar 12 away from the junction box 20. It can be understood that in other embodiments, one end of d and one end of L01 can overlap, and can be either the bending starting point closer to the first main body 111 or the bending starting point closer to the end of the second busbar 12 away from the junction box 20.

[0116] Similarly, in Figure 3 , Figure 4 and Figure 5 In the diagram, one end of d does not overlap with one end of L11. This is because the first busbar 11 has thickness, resulting in different bending starting points on both sides. Since d is the minimum distance between the first main body 111 and the second main body 121, the endpoint selected at the first main body 111 in the diagram is the bending starting point closer to the second main body 121. And since L11 is the distance from the end of the first busbar 11 away from the junction box 20 to the bending starting point of the first busbar 11 along the length of the first busbar 11, the selected endpoint is the bending starting point closer to the end of the first busbar 11 away from the junction box 20. It can be understood that in other embodiments, one end of d and one end of L11 can overlap, and can be either the bending starting point closer to the first main body 111 or the bending starting point closer to the end of the first busbar 11 away from the junction box 20.

[0117] Please see Figure 1 In some embodiments, the first end battery 311 includes a third solder strip 314, which is the solder strip connected to the first end battery 311 other than the first solder strip 3120 and the solder strip adjacent to the first solder strip 3120. The back contact battery assembly 100 satisfies the following formula:

[0118] D1 > D;

[0119] Where D is the minimum distance between two adjacent third weld strips 314.

[0120] Thus, the distance D1 from the first solder strip 3120 to the corresponding edge of the first end battery 311 is greater than the minimum distance D between two adjacent third solder strips 314 in the first end battery 311. This makes the distance D1 from the first solder strip 3120 to the corresponding edge of the first end battery 311 larger, thereby making the connection point between the first solder strip 3120 and the first busbar 11 farther away from the junction box 20. This makes it easier to bend the first busbar 11 and connect it to the first interface 21, which can reduce the risk that the first busbar 11 is difficult to connect to the first interface 21 when the first busbar 11 has high rigidity and is difficult to bend.

[0121] Specifically, D1 can be 1.01D, 1.1D, 1.2D, 1.5D, 1.8D, 2D, etc.

[0122] It can be understood that if there are multiple third weld strips 314, then the distance between adjacent third weld strips 314 can be multiple, and D can refer to the minimum value among these multiple distances. It can also be understood that the distance between two adjacent third weld strips 314 can be a fixed value or it can vary, and D can refer to the minimum distance between two adjacent third weld strips 314 whose distance varies.

[0123] In actual operation, the first solder strip 3120 can be moved away from the corresponding edge, thereby increasing the distance D1 between the first solder strip 3120 and the corresponding edge of the first end battery 311, so that D1 is greater than the minimum distance D between two adjacent third solder strips 314.

[0124] Please see Figure 1 In some embodiments, the first end battery 311 includes a third solder strip 314, which is the solder strip excluding the first solder strip 3120 and the solder strip adjacent to the first solder strip 3120 among the solder strips to which the first end battery 311 is connected. The back contact battery assembly 100 satisfies the following formula:

[0125] D1+D2+S1>3D;

[0126] Where D is the minimum distance between two adjacent third weld strips 314.

[0127] Thus, the sum of the distances from the adjacent solder strips connected to the adjacent two busbars to the corresponding cell edges, plus the distance between the two cells, is greater than the minimum value of the distance between the two adjacent third solder strips 314, which makes the spacing between the first solder strip 3120 and the second solder strip 3220 larger. This provides sufficient space for setting up the junction box 20, making it easier to install the junction box 20 between the first busbar 11 and the second busbar 12, which is beneficial to improving the production efficiency of photovoltaic modules.

[0128] Specifically, the value of D1+D2+S1 can be 3.01D, 3.1D, 3.2D, 3.5D, 3.8D, 4D, etc.

[0129] In actual operation, at least one of the following methods can be used to increase the value of D1+D2+S1: move the first solder strip 3120 away from the corresponding edge, thereby increasing the distance D1 between the first solder strip 3120 and the corresponding edge of the first end battery 311; move the second solder strip 3220 away from the corresponding edge, thereby increasing the distance D2 between the second solder strip 3220 and the corresponding edge of the second end battery 321; move the first end battery 311 away from the second end battery 321, thereby increasing the distance S1 between the first end battery 311 and the second end battery 321; move the second end battery 321 away from the first end battery 311, thereby increasing the distance S1 between the first end battery 311 and the second end battery 321.

[0130] For explanations and descriptions of D1, D2, S1, and D, please refer to the previous text. To avoid redundancy, they will not be repeated here.

[0131] Please see Figure 1 In some embodiments, the first end battery 311 includes a third solder strip 314, which is the solder strip connected to the first end battery 311 other than the first solder strip 3120 and the solder strip adjacent to the first solder strip 3120. The back contact battery assembly 100 satisfies the following formula:

[0132] D1+D2>2D;

[0133] Where D is the minimum distance between two adjacent third weld strips 314.

[0134] Thus, the sum of the distances from the adjacent solder strips connected to the adjacent two busbars to the corresponding cell edge is greater than twice the minimum distance of the two adjacent third solder strips 314. This makes the distances from the first solder strip 3120 and the second solder strip 3220 to their corresponding edges relatively large, providing sufficient space for the junction box 20. This facilitates the installation of the junction box 20 between the first busbar 11 and the second busbar 12, which is beneficial to improving the production efficiency of photovoltaic modules.

[0135] Specifically, the value of D1+D2 can be 2.01D, 2.1D, 2.2D, 2.5D, 2.8D, 3D, etc.

[0136] In actual operation, at least one of the following methods can be used to increase the value of D1+D2: move the first solder strip 3120 away from the corresponding edge, thereby increasing the distance D1 between the first solder strip 3120 and the corresponding edge of the first end battery 311; move the second solder strip 3220 away from the corresponding edge, thereby increasing the distance D2 between the second solder strip 3220 and the corresponding edge of the second end battery 321.

[0137] For explanations and descriptions of D1, D2, and D, please refer to the previous text. To avoid redundancy, they will not be repeated here.

[0138] Please see Figure 1 In some embodiments, the distance A1 between the first end battery 311 and the first busbar 11 is 2mm-4mm. For example, it is 2mm, 2.2mm, 2.5mm, 2.8mm, 3mm, 3.2mm, 3.5mm, 3.8mm, or 4mm.

[0139] In this way, the distance A1 between the first end battery 311 and the first busbar 11 is within a suitable range, which can avoid insufficient space left for the junction box 20 due to the distance being too small, or the first busbar 11 being easy to conduct with the heterogeneous grid lines or solder strips of the first end battery 311, and can also avoid wasting component space due to the distance being too large.

[0140] Preferably, the distance A1 between the first end battery 311 and the first busbar 11 is 2.9mm-3.3mm. For example, it is 2.9mm, 3mm, 3.1mm, 3.2mm, or 3.3mm. This further optimizes the distance A1 between the first end battery 311 and the first busbar 11, balancing the installation of the junction box 20, reducing the risk of short circuits, and minimizing wasted space. In one example, the distance A1 between the first end battery 311 and the first busbar 11 is 3.1mm.

[0141] Please see Figure 1 In some embodiments, the distance A2 between the second end battery 321 and the second busbar 12 is 2mm-4mm. For example, it is 2mm, 2.2mm, 2.5mm, 2.8mm, 3mm, 3.2mm, 3.5mm, 3.8mm, or 4mm.

[0142] This ensures that the distance A2 between the second end battery 321 and the second busbar 12 is within a suitable range. This avoids insufficient space left for the junction box 20 due to a small distance, or easy conduction between the second busbar 12 and the heterogeneous grid lines or solder strips of the second end battery 321. It also avoids wasting component space due to a large distance.

[0143] Preferably, the distance A2 between the second end battery 321 and the second busbar 12 is 2.9mm-3.3mm. For example, it is 2.9mm, 3mm, 3.1mm, 3.2mm, or 3.3mm. This further optimizes the distance A2 between the second end battery 321 and the second busbar 12, balancing the installation of the junction box 20, reducing the risk of short circuits, and minimizing wasted space. In one example, the distance A2 between the second end battery 321 and the second busbar 12 is 3.1mm.

[0144] In some embodiments, the back contact battery assembly 100 includes a battery string, which includes a first string 31 and a second string 32. The battery cells in the battery string include adjacent first cells and second cells. The chamfer of the first cell is located at the end of the first cell closer to the second cell, and the right angle of the second cell is located at the end of the second cell closer to the first cell.

[0145] This arrangement ensures that the chamfers and right angles of adjacent cells in the battery string are opposite each other. This avoids the problem of excessive distance and insufficient light utilization caused by chamfers and right angles, and also avoids the problem of excessive distance and greater risk of scratches caused by right angles and right angles.

[0146] Specifically, in a battery string, only one pair of adjacent cells may have chamfered and right-angled edges; in a battery string, multiple pairs or even all adjacent cells may have chamfered and right-angled edges; in a battery string, adjacent cells may have chamfered and right-angled edges, while other battery strings do not; or in multiple or even all battery strings, adjacent cells may have chamfered and right-angled edges. No specific limitations are imposed here.

[0147] In some embodiments, the back contact battery assembly 100 includes a battery string, which includes a first string 31 and a second string 32. The battery cells in the battery string include adjacent third and fourth cells, and the distance between the third and fourth cells is -2mm to 2mm. For example, -2mm, -1.5mm, -1mm, -0.5mm, 0mm, 0.5mm, 1mm, 1.5mm, and 2mm.

[0148] This ensures that the spacing between adjacent cells in the battery string is within a suitable range. It avoids the problem of excessively small spacing leading to excessively large areas of the cells being blocked during stacking, resulting in poor module power generation efficiency. It also avoids the problem of excessively large spacing leading to wasted module space.

[0149] It is understandable that when the third and fourth pieces overlap, the distance between the third and fourth pieces is negative.

[0150] Preferably, the distance between the third and fourth cells is -0.6mm to 0.6mm. For example, it could be -0.6mm, -0.5mm, -0.4mm, -0.2mm, 0mm, 0.2mm, 0.4mm, 0.5mm, or 0.6mm. This further optimizes the distance between the third and fourth cells, balancing module power generation efficiency and space utilization, resulting in better overall performance. In one example, the distance between the third and fourth cells is 0.5mm.

[0151] Please see Figure 2 In some embodiments, the back contact battery assembly 100 includes a first series structure 101 and a second series structure 102, located on both sides of the first busbar 11, with the second series structure 102 connected in parallel with the first series structure 101. This results in a higher current and a lower voltage in the back contact battery assembly 100.

[0152] Specifically, both the first series structure 101 and the second series structure 102 include a plurality of battery strings connected in series. The battery strings of the first series structure 101 include the aforementioned first string 31 and second string 32.

[0153] It is understood that in other embodiments, the first series structure 101 and the second series structure 102 may also be connected in series. The first series structure 101 may also include parallel units. The second series structure 102 may also include parallel units. No limitation is made here.

[0154] Please see Figure 1 In some embodiments, the distance A3 between the first series structure 101 and the second series structure 102 is 10mm-15mm. For example, it is 10mm, 11mm, 12mm, 13mm, 14mm, or 15mm.

[0155] This ensures that the distance A3 between the first series structure 101 and the second series structure 102 is within a suitable range, which can avoid the difficulty of placing the busbar and junction box 20 due to the distance being too small, and can also avoid the waste of component space due to the distance being too large.

[0156] Preferably, the distance A3 between the first series structure 101 and the second series structure 102 is 12mm-12.5mm. For example, it is 12mm, 12.1mm, 12.2mm, 12.3mm, 12.4mm, or 12.5mm. This further optimizes the distance between the first series structure 101 and the second series structure 102, taking into account the placement of the busbar and junction box 20, as well as the utilization of component space, resulting in a better overall effect. In one example, the distance A3 between the first series structure 101 and the second series structure 102 is 12.2mm.

[0157] Please see Figure 1In some embodiments, the distance A4 between the second series structure 102 and the first busbar 11 is 2mm-4mm. For example, it is 2mm, 2.5mm, 3mm, 3.5mm, or 4mm.

[0158] This ensures that the distance A4 between the second series structure 102 and the first busbar 11 is within a suitable range, avoiding the difficulty of placing the busbar and junction box 20 due to an excessively small distance, and also avoiding the waste of component space due to an excessively large distance.

[0159] Preferably, the distance A4 between the second series structure 102 and the first busbar 11 is 2.9mm-3.2mm. For example, it is 2.9mm, 3mm, 3.1mm, or 3.2mm. This further optimizes the distance between the second series structure 102 and the first busbar 11, balancing the placement of the busbar and junction box 20 with component space utilization, resulting in a better overall effect. In one example, the distance A4 between the second series structure 102 and the first busbar 11 is 3.1mm.

[0160] Please see Figure 7 and Figure 1 In some embodiments, the back contact battery assembly 100 includes a parallel bus bar 10, which includes a first bus bar 11 and a second bus bar 12.

[0161] The first series structure 101 includes a plurality of first battery strings 30 connected in series and arranged along a first direction. Each first battery string 30 includes a first string 31 and a second string 32. At least one first battery string 30 includes a first string end battery 301 and a first string end solder strip 302. The first string end battery 301 includes a first end battery 311 and a second end battery 321. The first string end solder strip 302 connects the first string end battery 301 and the parallel bus bar 10, and includes a first end solder strip 312 and a second end solder strip 322.

[0162] The second series structure 102 includes a plurality of second battery strings 40 connected in series and arranged along a first direction. At least one second battery string 40 includes a second string end battery 401 and a second string end solder strip 402. The second string end solder strip 402 connects the second string end battery 401 and the parallel bus bar 10.

[0163] The first end solder strip 302 is staggered from the second end solder strip 402.

[0164] In this way, the first string end solder strip 302 and the second string end solder strip 402 connected to the parallel bus bar 10 are staggered, which can avoid the large thickness caused by the overlap of the first string end solder strip 302 and the second string end solder strip 402, thereby reducing the risk of cell fragmentation during lamination.

[0165] Specifically, "the first end solder strip 302 and the second end solder strip 402 are staggered" means that there is a gap between the first end solder strip 302 and the second end solder strip 402, with no overlapping parts.

[0166] Please see Figure 7 In some embodiments, the minimum value w0 of the distance between the first end solder strip 302 and the second end solder strip 402 is greater than or equal to 0.5 mm. For example, it is 0.5 mm, 0.6 mm, 0.8 mm, 1 mm, 1.2 mm, 1.5 mm, or 2 mm.

[0167] This ensures that the minimum value of the distance w0 between the first end solder strip 302 and the second end solder strip 402 is within a suitable range, which can reduce the risk of overlap between the first end solder strip 302 and the second end solder strip 402 caused by the distance between them being too small.

[0168] It can be understood that there are multiple first-string end solder strips 302 and multiple second-string end solder strips 402, so the distance between the first-string end solder strips 302 and the second-string end solder strips 402 can be multiple, and w0 can refer to the minimum value among these multiple distances. It can also be understood that the distance between adjacent first-string end solder strips 302 and second-string end solder strips 402 can be a fixed value or it can vary, and w0 can refer to the minimum distance between the first-string end solder strips 302 and the second-string end solder strips 402 when the distance varies.

[0169] Please see Figure 7 In some embodiments, the edges of the first terminal battery 301 and the second terminal battery 401 are offset in the width direction of the parallel bus bar 10.

[0170] Thus, by staggering the first terminal battery 301 and the second terminal battery 401, the first terminal solder strip 302 connected to the first terminal battery 301 and the fourth terminal solder strip connected to the fourth terminal battery can be staggered.

[0171] Specifically, the edges of the first terminal battery 301 and the second terminal battery 401 are offset in the width direction of the parallel bus bar 10, meaning that the edges of the first terminal battery 301 and the fourth terminal battery do not overlap in the width direction of the parallel bus bar 10.

[0172] Please see Figure 7In some embodiments, the solder strips connected to the first terminal battery 301 include a first edge solder strip 303 and a second edge solder strip 304, the first edge solder strip 303 and the second edge solder strip 304 being closest to the two edges of the first terminal battery 301 in the length direction of the parallel bus bar 10; the solder strips connected to the second terminal battery 401 include a third edge solder strip 403 and a fourth edge solder strip 404, the third edge solder strip 403 and the fourth edge solder strip 404 being closest to the two edges of the second terminal battery 401 in the length direction of the parallel bus bar 10;

[0173] The back contact battery assembly 100 satisfies the following formula:

[0174] 0 < w0 ≤ |w1 - w2|;

[0175] 0 < w0 ≤ |w3 - w4|;

[0176] Wherein, w0 is the minimum distance between the first end solder strip 302 and the second end solder strip 402; w1 is the distance between the first edge solder strip 303 and the corresponding edge of the first end battery 301; w2 is the distance between the second edge solder strip 304 and the corresponding edge of the first end battery 301; w3 is the distance between the third edge solder strip 403 and the corresponding edge of the second end battery 401; and w4 is the distance between the fourth edge solder strip 404 and the corresponding edge of the second end battery 401.

[0177] For example, w0 is 0.1×|w1-w2|, 0.2×|w1-w2|, 0.3×|w1-w2|, 0.4×|w1-w2|, 0.5×|w1-w2|, 0.6×|w1-w2|, 0.7×|w1-w2|, 0.8×|w1-w2|, 0.9×|w1-w2|, 1×|w1-w2|.

[0178] Thus, the minimum value of the distance between the first end solder strip 302 and the second end solder strip 402 is less than or equal to the absolute value of the difference between the distances between the two edge solder strips of the first end battery 301 and their corresponding edges, and is less than or equal to the absolute value of the difference between the distances between the two edge solder strips of the second end battery 401 and their corresponding edges. This ensures that the minimum value of the distance between the first end solder strip 302 and the second end solder strip 402 is within a suitable range, which can avoid the waste of component space caused by the minimum value of the distance being too large.

[0179] Specifically, w1 is the distance between the first edge solder strip 303 and the corresponding edge of the first terminal battery 301. Note that "corresponding edge" here refers to the edge of the first terminal battery 301 that is closer to the first edge solder strip 303 among the two edges in the first direction. The "distance" here refers to the distance in the first direction. That is, w1 is the distance from the first edge solder strip 303 to the edge of the first terminal battery 301 that is closer to the first edge solder strip 303 among the two edges in the first direction.

[0180] Specifically, w2 is the distance between the second edge solder strip 304 and the corresponding edge of the first terminal battery 301. Note that "corresponding edge" here refers to the edge of the first terminal battery 301 that is closer to the second edge solder strip 304 among the two edges in the first direction. The "distance" here refers to the distance in the first direction. That is, w2 is the distance from the second edge solder strip 304 in the first direction to the edge of the first terminal battery 301 that is closer to the second edge solder strip 304 among the two edges in the first direction.

[0181] Specifically, w3 is the distance between the third edge solder strip 403 and the corresponding edge of the second terminal battery 401. Note that "corresponding edge" here refers to the edge of the second terminal battery 401 that is closer to the third edge solder strip 403 among the two edges in the first direction. The "distance" here refers to the distance in the first direction. That is, w3 is the distance from the third edge solder strip 403 in the first direction to the edge of the second terminal battery 401 that is closer to the third edge solder strip 403 among the two edges in the first direction.

[0182] Specifically, w4 is the distance between the fourth edge solder strip 404 and the corresponding edge of the second terminal battery 401. Note that "corresponding edge" here refers to the edge of the second terminal battery 401 that is closer to the fourth edge solder strip 404 among the two edges in the first direction. The "distance" here refers to the distance in the first direction. That is, w4 is the distance from the fourth edge solder strip 404 in the first direction to the edge of the second terminal battery 401 that is closer to the fourth edge solder strip 404 among the two edges in the first direction.

[0183] Please see Figure 7 In some embodiments, the back contact battery assembly 100 satisfies the following formula:

[0184] 0.25×|w1-w2|≤w0;

[0185] 0.25×|w3-w4|≤w0.

[0186] For example, w0 is 0.25×|w1-w2|, 0.26×|w1-w2|, 0.3×|w1-w2|, 0.4×|w1-w2|, 0.5×|w1-w2|, 0.6×|w1-w2|, 0.7×|w1-w2|, 0.8×|w1-w2|, 0.9×|w1-w2|, 1×|w1-w2|.

[0187] Thus, the minimum value of the distance between the first string end solder strip 302 and the second string end solder strip 402 is greater than or equal to 0.25 times the absolute value of the difference between the distances between the two edge solder strips of the first string end battery 301 and their corresponding edges, and is also greater than or equal to 0.25 times the absolute value of the difference between the distances between the two edge solder strips of the second string end battery 401 and their corresponding edges. This further optimizes the range of the minimum value of the distance between the first string end solder strip 302 and the second string end solder strip 402, and can avoid the risk of the first string end solder strip 302 and the second string end solder strip 402 overlapping due to the minimum value of the distance being too small.

[0188] Please see Figure 7 In some embodiments, 0 < w0 ≤ 1.5 mm. w0 is, for example, 0.1 mm, 0.2 mm, 0.5 mm, 0.8 mm, 1 mm, 1.2 mm, or 1.5 mm.

[0189] This ensures that the minimum value of the distance w0 between the first end solder strip 302 and the second end solder strip 402 is within a suitable range, which can reduce the risk of wasted space caused by an excessively large distance between the first end solder strip 302 and the second end solder strip 402.

[0190] Preferably, w0 is 0.4mm-0.6mm. For example, it can be 0.4mm, 0.45mm, 0.5mm, 0.55mm, or 0.6mm. This further optimizes the staggered distance between the first end solder strip 302 and the second end solder strip 402, avoiding solder strip overlap and wasted space, resulting in a better overall effect. In one example, w0 is 0.5mm.

[0191] Please see Figure 7 In some embodiments, w1 is 0.5mm-5mm. For example, it is 0.5mm, 0.8mm, 0.965mm, 1mm, 2mm, 3mm, 4mm, or 5mm.

[0192] This ensures that the distance between the first edge solder strip 303 and the corresponding edge of the first string battery 301 is within a suitable range, which can avoid the difficulty of soldering caused by the distance being too small, and can also avoid the poor current collection effect caused by the distance being too large.

[0193] Please see Figure 7In some embodiments, w2 is greater than w1, ranging from 0.5mm to 10mm. For example, w2 is 0.5mm, 0.8mm, 1mm, 3mm, 4mm, 4.805mm, 6mm, 9mm, or 10mm.

[0194] This ensures that the distance between the second edge solder strip 304 and the corresponding edge of the first string battery 301 is within a suitable range, avoiding the difficulty of soldering due to the distance being too small, and also avoiding the poor current collection effect due to the distance being too large.

[0195] Please see Figure 7 In some embodiments, w3 is 0.5mm-5mm. For example, it is 0.5mm, 0.8mm, 0.965mm, 1mm, 2mm, 3mm, 4mm, or 5mm.

[0196] This ensures that the distance between the third edge solder strip 403 and the corresponding edge of the second string terminal battery 401 is within a suitable range, avoiding the difficulty of soldering due to the distance being too small, and also avoiding the poor current collection effect due to the distance being too large.

[0197] Please see Figure 7 In some embodiments, w4 is greater than w3, ranging from 0.5mm to 10mm. For example, w4 is 0.5mm, 0.8mm, 1mm, 3mm, 4mm, 4.805mm, 6mm, 9mm, or 10mm.

[0198] This ensures that the distance between the fourth edge solder strip 404 and the corresponding edge of the second string battery 401 is within a suitable range, avoiding the difficulty of soldering due to the distance being too small, and also avoiding the poor current collection effect due to the distance being too large.

[0199] Please see Figure 1 In some embodiments, the back contact battery assembly 100 satisfies the following formula: D < E < 2D;

[0200] Where D is the minimum distance between two adjacent third welding strips 314, the third welding strip 314 is the welding strip connected to the first end battery 311 except for the first welding strip 3120 and the welding strip adjacent to the first welding strip 3120, and E is the distance between the first welding strip 3120 and the second welding strip 3220.

[0201] This provides sufficient space for the junction box 20, making it easy to install the junction box 20 between adjacent first busbar 11 and second busbar 12, which helps to improve the production efficiency of the back contact battery assembly 100.

[0202] It is understandable that if E is less than or equal to D, the distance between the first solder strip 3120 and the second solder strip 3220 will be too small. This will easily lead to insufficient space for the junction box 20, or difficulty in connecting the more rigid and difficult-to-bend busbars to the junction box 20, thus affecting the production efficiency of the back contact battery module 100. If E is greater than or equal to 2D, the space reserved for the junction box 20 will be too large, easily leading to wasted space within the module, and even wasted busbars, resulting in higher costs for the back contact battery module 100.

[0203] Specifically, the "distance between two adjacent third weld strips 314" here refers to the distance in the first direction. That is, D is the minimum distance between two adjacent third weld strips 314 in the first direction.

[0204] It can be understood that if there are multiple third weld strips 314, then the distance between adjacent third weld strips 314 can be multiple, and D can refer to the minimum value among these multiple distances. It can also be understood that the distance between two adjacent third weld strips 314 can be a fixed value or it can vary, and D can refer to the minimum distance between two adjacent third weld strips 314 whose distance varies.

[0205] Specifically, the "distance between the first solder strip 3120 and the second solder strip 3220" here refers to the distance in the first direction. That is, E is the distance between the first solder strip 3120 and the second solder strip 3220 in the first direction. Please note that when the distance between the first solder strip 3120 and the second solder strip 3220 in the first direction changes, E can refer to the minimum value of the distance between the first solder strip 3120 and the second solder strip 3220 in the first direction; it can also refer to the maximum value of the distance between the first solder strip 3120 and the second solder strip 3220 in the first direction.

[0206] Specifically, E can be 1.01D, 1.2D, 1.5D, 1.8D, 1.9D, or 1.99D.

[0207] In some embodiments, D is 3mm-10mm. For example, it is 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, or 10mm.

[0208] In this way, the distance D between two adjacent third solder strips 314 is within a suitable range, which can avoid the excessive number of solder strips required and the high cost caused by the distance between two adjacent third solder strips 314 being too small, and can also avoid the poor effect of current conduction caused by the distance between two adjacent third solder strips 314 being too large.

[0209] Specifically, D ranges from 6mm to 8mm. Examples include 6mm, 6.2mm, 6.5mm, 6.86mm, 7mm, 7.2mm, 7.5mm, 7.8mm, and 8mm. This further optimizes the range of D, balancing cost and current extraction efficiency, resulting in better overall performance.

[0210] In some embodiments, E is greater than 3 mm and less than 20 mm. For example, it is 3.1 mm, 3.2 mm, 4 mm, 5 mm, 8 mm, 10 mm, 12 mm, 15 mm, 18 mm, 19 mm, or 19.9 mm.

[0211] This ensures that the distance E between the first solder strip 3120 and the second solder strip 3220 is within a suitable range, which can avoid the difficulty in installing the junction box 20 due to the distance between the first solder strip 3120 and the second solder strip 3220 being too small, and can also avoid the waste of component space due to the distance between the first solder strip 3120 and the second solder strip 3220 being too large.

[0212] Specifically, E is 17mm-19mm. For example, it can be 17mm, 17.5mm, 17.8mm, 18mm, 18.12mm, 18.5mm, or 19mm. This further optimizes the range of the distance E between the first solder strip 3120 and the second solder strip 3220, balancing the installation of the junction box 20 with space saving, resulting in a better overall effect.

[0213] In summary, the back contact battery assembly 100 of this application embodiment includes:

[0214] The first busbar 11 and the second busbar 12 are respectively connected to the first interface 21 and the second interface 22 of the junction box 20;

[0215] The adjacent first string 31 and second string 32 each include a number of battery cells connected in series. The first string 31 includes a first end battery 311 and a first end solder strip 312. The first end solder strip 312 connects the first end battery 311 and the first busbar 11, including the first solder strip 3120 closest to the second busbar 12. The second string 32 includes a second end battery 321 and a second end solder strip 322. The second end solder strip 322 connects the second end battery 321 and the second busbar 12, including the second solder strip 3220 closest to the first busbar 11.

[0216] The first solder strip 3120 is the outermost solder strip among the solder strips connected to the first end battery 311; the second solder strip 3220 is the solder strip adjacent to the outermost solder strip among the solder strips connected to the second end battery 321.

[0217] The back contact battery assembly 100 satisfies the following formula: D < E < 2D;

[0218] Where D is the minimum distance between two adjacent third welding strips 314, the third welding strip 314 is the welding strip connected to the first end battery 311 except for the first welding strip 3120 and the welding strip adjacent to the first welding strip 3120, and E is the distance between the first welding strip 3120 and the second welding strip 3220.

[0219] The back contact battery assembly 100 of this application embodiment has sufficient space for setting up the junction box 20, since the adjacent first solder strip 3120 and second solder strip 3220 connected to two adjacent busbars are respectively the outermost solder strip and the second edge solder strip, and the distance between the first solder strip 3120 and the second solder strip 3220 is between 1 and 2 times the minimum value of the distance between two adjacent third solder strips 314. This facilitates the installation of the junction box 20 between the adjacent first busbar 11 and the second busbar 12, which is beneficial to improving the production efficiency of the back contact battery assembly 100.

[0220] In addition, the back contact battery module 100 may also include a metal frame, a backsheet, photovoltaic glass, and an encapsulating film. The encapsulating film can be filled between the front and back of the battery cells, as well as between the photovoltaic glass and adjacent battery cells. As a filler, it can be a transparent colloid with good light transmittance and aging resistance. For example, the encapsulating film can be EVA film or POE film. The specific choice can be made according to the actual situation and is not limited here.

[0221] Photovoltaic glass can be applied to the encapsulating film on the front of the solar cell. This photovoltaic glass can be ultra-clear glass, possessing high light transmittance, high transparency, and superior physical, mechanical, and optical properties. For example, ultra-clear glass can achieve a light transmittance of over 92%, protecting the solar cell while minimizing impact on its efficiency. Simultaneously, the encapsulating film bonds the photovoltaic glass and the solar cell together, providing sealing, insulation, and waterproofing / moisture protection for the cell.

[0222] The backsheet can be attached to the adhesive film on the back of the solar cell. The backsheet protects and supports the solar cell, providing reliable insulation, water resistance, and aging resistance. Multiple backsheet options are available, typically including tempered glass, acrylic glass, aluminum alloy TPT composite adhesive film, etc., and the specific choice depends on the specific circumstances and is not limited here. The backsheet, solar cell, adhesive film, and photovoltaic glass can be mounted on a metal frame. The metal frame serves as the main external support structure for the entire back-contact solar module 100, providing stable support and installation. For example, the back-contact solar module 100 can be installed at the desired location using the metal frame.

[0223] The photovoltaic system of this application embodiment includes the back contact battery module 100 described above.

[0224] In the photovoltaic system of this application embodiment, since the adjacent first solder strips 3120 and second solder strips 3220 connected to two adjacent busbars are respectively the outermost solder strip and the second-edge solder strip, and the distance between the first solder strip 3120 and the second solder strip 3220 is between 1 and 2 times the minimum value of the distance between two adjacent third solder strips 314, sufficient space can be provided for setting the junction box 20, which is convenient for installing the junction box 20 between adjacent first busbars 11 and second busbars 12, which is beneficial to improving the production efficiency of the back contact battery module 100.

[0225] In one example, photovoltaic (PV) systems can be applied to PV power plants, such as ground-mounted, rooftop, and floating power plants, as well as to equipment or devices that utilize solar energy for power generation, such as user solar power supplies, solar streetlights, solar cars, and solar buildings. Of course, it's understandable that the application scenarios for PV systems are not limited to these; that is, PV systems can be applied in all areas that require solar energy for power generation. Taking a PV power grid as an example, a PV system can include PV arrays, combiner boxes, and inverters. A PV array can be an array combination of multiple back-contact battery modules 100. For example, multiple back-contact battery modules 100 can form multiple PV arrays. The PV arrays are connected to combiner boxes, which collect the current generated by the PV arrays. The collected current flows through an inverter, converts it into AC power required by the mains grid, and then connects to the mains grid to achieve solar power supply.

[0226] In the description of this specification, the references to terms such as "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0227] Furthermore, the above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A back-contact battery assembly, characterized in that, include: The first busbar and the second busbar are respectively connected to the first interface and the second interface of the junction box; The first and second adjacent strings each include a number of battery cells connected in series. The first string includes a first end battery and a first end solder strip. The first end solder strip connects the first end battery to the first busbar and includes the first solder strip closest to the second busbar. The second string includes a second end battery and a second end solder strip. The second end solder strip connects the second end battery to the second busbar and includes the second solder strip closest to the first busbar. The first solder strip is the outermost solder strip among the solder strips connected to the first end battery; the second solder strip is the solder strip adjacent to the outermost solder strip among the solder strips connected to the second end battery. The back contact battery assembly satisfies the following formula: D < E < 2D; Where D is the minimum distance between two adjacent third solder strips, the third solder strip is the solder strip connected to the first end battery excluding the first solder strip and the solder strip adjacent to the first solder strip, and E is the distance between the first solder strip and the second solder strip.

2. The back contact battery assembly according to claim 1, characterized in that, D is 3mm-10mm.

3. The back contact battery assembly according to claim 1, characterized in that, E is greater than 3mm and less than 20mm.

4. The back contact battery assembly according to claim 1, characterized in that, The back contact battery assembly satisfies the following formula: D1+D2+S1>B+L02-L01; Wherein, D1 is the distance from the first solder strip to the corresponding edge of the first end battery, D2 is the distance from the second solder strip to the corresponding edge of the second end battery, S1 is the distance between the first end battery and the second end battery, B is the distance from the first interface to the second interface, L01 is the distance from the end of the second busbar away from the junction box to the bending start point of the second busbar in the length direction of the busbar, and L02 is the distance from the end of the second busbar away from the junction box to the second interface in the length direction of the busbar.

5. The back contact battery assembly according to claim 4, characterized in that, The back contact battery assembly satisfies the following formula: D1+D2+S1>B+L02-L01+L12-L11; Wherein, L11 is the distance from the end of the first busbar away from the junction box to the bending point of the first busbar in the length direction of the busbar, and L12 is the distance from the end of the first busbar away from the junction box to the first interface in the length direction of the busbar.

6. The back contact battery assembly according to claim 1, characterized in that, The back contact battery assembly includes a third string located on the side of the second string opposite to the first string. The third string includes a third end battery and a third end solder strip. The third end battery is located on the side of the second end battery opposite to the first end battery. The third end solder strip connects the third end battery to the second busbar. The back contact battery assembly satisfies the following formula: S1 > S2. Wherein, S1 is the distance between the first end battery and the second end battery, and S2 is the distance between the third end battery and the second end battery.

7. The back contact battery assembly according to claim 1, characterized in that, The first end battery includes a third solder strip, which is the solder strip connected to the first end battery excluding the first solder strip and the solder strip adjacent to the first solder strip. The back contact battery assembly satisfies the following formula: D1 > D; Wherein, D1 is the distance from the first solder strip to the corresponding edge of the first end battery.

8. The back contact battery assembly according to claim 1, characterized in that, The first end battery includes a third solder strip, which is the solder strip connected to the first end battery excluding the first solder strip and the solder strip adjacent to the first solder strip. The back contact battery assembly satisfies the following formula: D1+D2+S1>3D; Wherein, D1 is the distance from the first solder strip to the corresponding edge of the first end battery, D2 is the distance from the second solder strip to the corresponding edge of the second end battery, and S1 is the distance between the first end battery and the second end battery.

9. The back contact battery assembly according to claim 1, characterized in that, The back contact battery assembly includes a first series structure and a second series structure, which are located on both sides of the first busbar, and the second series structure is connected in parallel with the first series structure. The back contact battery assembly includes parallel busbars, which include a first busbar and a second busbar; The first series structure includes a plurality of first battery strings connected in series and arranged along a first direction. The first battery string includes a first string and a second string. At least one first battery string includes a first string end battery and a first string end solder strip. The first string end battery includes a first end battery and a second end battery. The first string end solder strip connects the first string end battery and the parallel bus bar, including the first end solder strip and the second end solder strip. The second series structure includes a plurality of second battery strings connected in series and arranged along a first direction, at least one of the second battery strings including a second string terminal battery and a second string terminal solder strip, the second string terminal solder strip connecting the second string terminal battery and the parallel bus bar; The first terminal solder strip is staggered from the second terminal solder strip.

10. The back contact battery assembly according to claim 9, characterized in that, The solder strips connected to the first series-terminated battery include a first edge solder strip and a second edge solder strip, the first edge solder strip and the second edge solder strip being closest to the two edges of the first series-terminated battery in the length direction of the parallel busbar, respectively; the solder strips connected to the second series-terminated battery include a third edge solder strip and a fourth edge solder strip, the third edge solder strip and the fourth edge solder strip being closest to the two edges of the second series-terminated battery in the length direction of the parallel busbar, respectively; The back contact battery assembly satisfies the following formula: 0 < w0 ≤ |w1 - w2|; 0 < w0 ≤ |w3 - w4|; Wherein, w0 is the minimum distance between the first and second serial terminal solder strips; w1 is the distance between the first edge solder strip and the corresponding edge of the first serial terminal battery; w2 is the distance between the second edge solder strip and the corresponding edge of the first serial terminal battery; w3 is the distance between the third edge solder strip and the corresponding edge of the second serial terminal battery; and w4 is the distance between the fourth edge solder strip and the corresponding edge of the second serial terminal battery.

11. The back contact battery assembly according to claim 10, characterized in that, The back contact battery assembly satisfies the following formula: 0.25×|w1-w2|≤w0; 0.25×|w3-w4|≤w0.

12. A photovoltaic system, characterized in that, Includes the back contact battery assembly as described in any one of claims 1-11.

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