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 located at an end region of the back contact battery assembly; 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 the outermost solder strip in the solder strips connected with the second end battery; the back contact battery assembly satisfies the following formula: y > 2x.

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, battery strings are typically formed by connecting solar cells in series using solder ribbons. Busbars are then used to connect the solder ribbons of the cells located at the ends of the module within the battery string, enabling the corresponding battery strings to be connected in series or in parallel. However, the distance between adjacent battery strings connected to different busbars is usually quite close, leading to a higher risk of leakage.

[0003] Therefore, how to reduce the leakage risk of back-contact battery components 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 reduce the leakage risk of the back-contact battery module.

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

[0006] The first busbar and the second busbar are located in the end region of the back contact battery assembly;

[0007] 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.

[0008] The first solder strip is the outermost solder strip among the solder strips to which the first end battery is connected; the second solder strip is the outermost solder strip among the solder strips to which the second end battery is connected.

[0009] The back contact battery assembly satisfies the following formula:

[0010] y > 2x;

[0011] Where x 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 y is the distance between the first solder strip and the second solder strip.

[0012] Specifically, x is 2mm-10mm.

[0013] Specifically, y is greater than 4mm.

[0014] Specifically, y is 5mm-20mm.

[0015] Specifically, the number of battery cells included in the first string is even;

[0016] And / or, the number of battery cells included in the second string is even.

[0017] Specifically, the back contact battery assembly satisfies the following formula:

[0018]

[0019] Where z1 is the distance from the first solder strip to the corresponding edge of the first end battery, z2 is the distance from the second solder strip to the corresponding edge of the second end battery, and z0 is the distance between the first end battery and the second end battery.

[0020] Specifically, the back contact battery assembly satisfies the following formula:

[0021] x = z1 = z2.

[0022] Specifically, the back contact battery assembly includes:

[0023] The third and fourth busbars are connected to the first and second interfaces of the junction box, respectively;

[0024] The third string adjacent to the second string is located on the side of the second string away from the first string, and includes several battery cells connected in series. The third string includes a third end battery and a third end solder strip. The third end solder strip connects the third end battery to the third busbar, including a fourth solder strip closest to the fourth busbar.

[0025] The second string includes a fourth end battery and a fourth end solder strip, the fourth end solder strip connecting the fourth end battery to the fourth busbar, including a fifth solder strip closest to the third busbar;

[0026] The fourth solder strip is the solder strip adjacent to the outermost solder strip among the solder strips connected to the first end battery; the fifth solder strip is the solder strip adjacent to the outermost solder strip among the solder strips connected to the second end battery.

[0027] Specifically, the back contact battery assembly satisfies the following formula:

[0028] E > 3D;

[0029] Where D is the minimum distance between two adjacent sixth solder strips, the sixth solder strip is the solder strip connected to the third end battery excluding the fourth solder strip and the solder strip adjacent to the fourth solder strip, and E is the distance between the fourth solder strip and the fifth solder strip.

[0030] Specifically, the distance between the third end battery and the fourth end battery is 0.5mm-15mm.

[0031] Specifically, the distance between the first interface and the second interface is 3mm-15mm.

[0032] The photovoltaic system provided in this application includes the back-contact battery module of any of the above.

[0033] In the back contact battery module and photovoltaic system of this application embodiment, since the adjacent first and second solder strips connected to the two adjacent busbars located at the end region of the module are both the outermost solder strips, and the spacing is greater than twice the spacing between two adjacent solder strips in the first end battery excluding the first solder strip and the solder strip adjacent to the first solder strip, the spacing between the first solder strip and the second solder strip can be larger, thereby reducing the risk of leakage caused by the small spacing between the first solder strip and the second solder strip. Attached Figure Description

[0034] Figure 1 This is a partial structural schematic diagram of a back contact battery assembly according to an embodiment of this application;

[0035] Figure 2 This is a schematic diagram of the structure of a back contact battery assembly according to an embodiment of this application;

[0036] Figure 3 This is a partial structural schematic diagram of a back contact battery assembly according to an embodiment of this application;

[0037] Figure 4 This is a partial structural schematic diagram of a back contact battery assembly according to an embodiment of this application;

[0038] Explanation of key component symbols:

[0039] Back contact battery assembly 100, first series structure 101, second series structure 102, first busbar 11, second busbar 12; first battery string 20, first string end battery 201, first string end solder strip 202, first edge solder strip 203, second edge solder strip 204, second battery string 50, second string end battery 501, second string end solder strip 502, third edge solder strip 503, fourth edge solder strip 504; first string 21, first end battery 211, first end solder strip 212, first solder strip 2120, first non-end solder strip 2 13. Third welding strip 214; Second string 22, Second end battery 221, Second end welding strip 222, Second welding strip 2220, Second non-end welding strip 223, Fourth end battery 224, Fourth end welding strip 225, Fifth welding strip 2250, Fourth non-end welding strip 226, Sixth welding strip 227; Third string 23, Third end battery 231, Third end welding strip 232, Fourth welding strip 2320, Third non-end welding strip 233, Third busbar 31, Fourth busbar 32, Junction box 40, First interface 41, Second interface 42. Detailed Implementation

[0040] 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.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] Please see Figure 1 and Figure 2 The back contact battery assembly 100 of this application embodiment includes:

[0047] The first busbar 11 and the second busbar 12 are located in the end region of the back contact battery assembly 100;

[0048] The adjacent first string 21 and second string 22 each include a number of battery cells connected in series. The first string 21 includes a first end battery 211 and a first end solder strip 212. The first end solder strip 212 connects the first end battery 211 to the first bus bar 11 and includes a first solder strip 2120 closest to the second bus bar 12. The second string 22 includes a second end battery 221 and a second end solder strip 222. The second end solder strip 222 connects the second end battery 221 to the second bus bar 12 and includes a second solder strip 2220 closest to the first bus bar 11.

[0049] The first solder strip 2120 is the outermost solder strip among the solder strips connected to the first end battery 211; the second solder strip 2220 is the outermost solder strip among the solder strips connected to the second end battery 221.

[0050] The back contact battery assembly 100 satisfies the following formula:

[0051] y > 2x;

[0052] Where x is the minimum distance between two adjacent third welding strips 214, the third welding strip 214 is the welding strip connected to the first end battery 211 except for the first welding strip 2120 and the welding strip adjacent to the first welding strip 2120, and y is the distance between the first welding strip 2120 and the second welding strip 2220.

[0053] In the back contact battery assembly 100 of this application embodiment, since the adjacent first solder strips 2120 and second solder strips 2220 connected to the two adjacent busbars located at the end region of the assembly are both the outermost solder strips, and the spacing between them is greater than twice the spacing between the two adjacent solder strips in the first end battery 211 excluding the first solder strip 2120 and the solder strip adjacent to the first solder strip 2120, the spacing between the first solder strip 2120 and the second solder strip 2220 can be larger, thereby reducing the risk of leakage caused by the small spacing between the first solder strip 2120 and the second solder strip 2220.

[0054] Specifically, the end region of the back contact battery assembly 100 may include the region outside the battery cell or the region inside the battery cell. That is, the first busbar 11 and the second busbar 12 may be located in the end region outside the battery cell, such as... Figure 1 and Figure 2 As shown; the first busbar 11 and the second busbar 12 may also be located in the end region within the battery cell.

[0055] exist Figure 1 and Figure 2In the example, the first busbar 11 and the second busbar 12 are respectively located outside the first end battery 211 and the second end battery 221. This results in a simpler structure, lower manufacturing complexity, and improved module production efficiency. It is understood that in other examples, the first busbar 11 and the second busbar 12 can be located on the back side of the first end battery 211 and the second end battery 221, respectively. In this way, when viewed from the front of the module, the busbars are obscured by the batteries, achieving a visually concealed effect.

[0056] 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 20, including a first string 21, a second string 22, and a third string 23. The battery strings in the second series structure 102 are second battery strings 50.

[0057] Specifically, the first string 21 includes a number of solar cells connected in series. For example, the first string 21 may include 2, 3, 4, or other numbers of solar cells. Similarly, the second string 22 includes a number of solar cells connected in series. For example, the second string 22 may include 2, 3, 4, or other numbers of solar cells. The number of solar cells in the first string 21 and the second string 22 is not limited here.

[0058] 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.

[0059] Specifically, the first string 21 includes a first end battery 211, a first end solder strip 212, and a first non-end solder strip 213. The first end solder strip 212 connects the first end battery 211 to the first busbar 11. The first non-end solder strip 213 connects the first end battery 211 to the battery cell adjacent to the first end battery 211. One of the first end solder strip 212 and the first non-end solder strip 213 is electrically connected to the positive grid line of the first end battery 211, and the other is electrically connected to the negative grid line of the first end battery 211.

[0060] Furthermore, the first end solder strip 212 includes a first solder strip 2120 closest to the second busbar 12. In other words, there are multiple first end solder strips 212, and the first end solder strip 212 closest to the second busbar 12 is the first solder strip 2120.

[0061] Furthermore, the first solder strip 2120 is the outermost solder strip among the solder strips connected to the first end battery 211. In other words, the first solder strip 2120 is the solder strip closest to the second busbar 12 and located at the outermost edge between the first end solder strip 212 and the first non-end solder strip 213. That is, there is no first non-end solder strip 213 between the first solder strip 2120 and the second busbar 12.

[0062] Specifically, the second string 22 includes a second end battery 221, a second end solder strip 222, and a second non-end solder strip 223. The second end solder strip 222 connects the second end battery 221 to the second busbar 12. The second non-end solder strip 223 connects the second end battery 221 to the battery cell adjacent to the second end battery 221. One of the second end solder strip 222 and the second non-end solder strip 223 is electrically connected to the positive grid line of the second end battery 221, and the other is electrically connected to the negative grid line of the second end battery 221.

[0063] Furthermore, the second end solder strip 222 includes a second solder strip 2220 that is closest to the first busbar 11. In other words, there are multiple second end solder strips 222, and the second end solder strip 222 that is closest to the first busbar 11 is the second solder strip 2220.

[0064] Furthermore, the second solder strip 2220 is the outermost solder strip among the solder strips connected to the second end battery 221. In other words, the second solder strip 2220 is the solder strip closest to the first busbar 11 and located at the outermost edge among the second end solder strip 222 and the second non-end solder strip 223. That is, there is no second non-end solder strip 223 between the second solder strip 2220 and the first busbar 11.

[0065] Specifically, the back contact battery assembly 100 satisfies the following formula: y > 2x.

[0066] For example, y can be 2.01x, 2.1x, 2.5x, 3x, or 4x. No specific limit is imposed here.

[0067] Specifically, the "distance between two adjacent third weld strips 214" here refers to the distance in the first direction. That is, x is the minimum distance between two adjacent third weld strips 214 in the first direction.

[0068] It can be understood that if there are multiple third weld strips 214, then the distance between adjacent third weld strips 214 can be multiple, and x can refer to the minimum value among these multiple distances. It can also be understood that the distance between two adjacent third weld strips 214 can be a fixed value or it can vary, and x can refer to the minimum distance between two adjacent third weld strips 214 whose distance varies.

[0069] Specifically, the "distance between the first solder strip 2120 and the second solder strip 2220" here refers to the distance in the first direction. That is, y is the distance between the first solder strip 2120 and the second solder strip 2220 in the first direction. Please note that when the distance between the first solder strip 2120 and the second solder strip 2220 in the first direction changes, y can refer to the minimum value of the distance between the first solder strip 2120 and the second solder strip 2220 in the first direction; it can also refer to the maximum value of the distance between the first solder strip 2120 and the second solder strip 2220 in the first direction.

[0070] In some embodiments, x is 2mm-10mm. For example, it is 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, or 10mm.

[0071] In this way, the distance x between two adjacent third solder strips 214 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 214 being too small, and can also avoid the poor effect of current conduction caused by the distance between two adjacent third solder strips 214 being too large.

[0072] Specifically, x ranges from 6mm to 8mm. Examples include 6mm, 6.2mm, 6.5mm, 6.86mm, 7mm, 7.2mm, 7.5mm, 7.8mm, and 8mm. Further optimizing the range of x balances cost and current extraction efficiency, resulting in better overall performance.

[0073] In some embodiments, y is greater than 4 mm. For example, it is 4.1 mm, 4.2 mm, 5 mm, 8 mm, 10 mm, 12 mm, 15 mm, 18 mm, 19 mm, 20 mm, or 25 mm.

[0074] This ensures that the distance y between the first solder strip 2120 and the second solder strip 2220 is within a suitable range, thus avoiding the risk of leakage due to an excessively small distance between them.

[0075] In some embodiments, y is 5mm-20mm. For example, it is 5mm, 5.2mm, 6mm, 7mm, 8mm, 10mm, 12mm, 15mm, 18mm, 19mm, or 20mm.

[0076] Thus, further optimizing the distance between the first solder strip 2120 and the second solder strip 2220, so that the distance between the first solder strip 2120 and the second solder strip 2220 is within a suitable range, can avoid the risk of leakage caused by the distance between the first solder strip 2120 and the second solder strip 2220 being too small, and can also avoid the waste of component space caused by the distance between the first solder strip 2120 and the second solder strip 2220 being too large.

[0077] Specifically, y is 9mm-13mm. For example, 9mm, 10mm, 11mm, 11.21mm, 12mm, and 13mm. This further optimizes the range of distance between the first solder strip 2120 and the second solder strip 2220, taking into account both reducing the risk of leakage and saving space, resulting in a better overall effect.

[0078] In some embodiments, the number of battery cells included in the first string 21 is even. This ensures that the first solder strip 2120 is the outermost solder strip among the solder strips to which the first end battery 211 is connected.

[0079] In some embodiments, the number of battery cells included in the second string 22 is even. This ensures that the second solder strip 2220 is the outermost solder strip among the solder strips to which the second end battery 221 is connected.

[0080] Please see Figure 1 In some embodiments, the back contact battery assembly 100 satisfies the following formula:

[0081]

[0082] Wherein, z1 is the distance from the first solder strip 2120 to the corresponding edge of the first end battery 211, z2 is the distance from the second solder strip 2220 to the corresponding edge of the second end battery 221, and z0 is the distance between the first end battery 211 and the second end battery 221.

[0083] Thus, the difference between the distance between two adjacent third solder strips 214 in the first end battery 211 and half the sum of the first solder strip 2120 and the second solder strip 2220 is less than half the distance between the first end battery 211 and the second end battery 221. Therefore, the distance z0 between the first end battery 211 and the second end battery 221 can be larger, thereby increasing the distance between the first solder strip 2120 and the second solder strip 2220 and reducing the risk of leakage caused by the small spacing between the first solder strip 2120 and the second solder strip 2220.

[0084] Specifically, z1 is the distance from the first solder strip 2120 to the corresponding edge of the first end battery 211. Note that "corresponding edge" here refers to the edge of the first end battery 211 that is closer to the first solder strip 2120 among the two edges in the first direction. The "distance" here refers to the distance in the first direction. That is, z1 is the distance in the first direction from the first solder strip 2120 to the edge of the first end battery 211 that is closer to the first solder strip 2120 among the two edges in the first direction.

[0085] Specifically, z2 is the distance from the second solder strip 2220 to the corresponding edge of the second end battery 221. Note that "corresponding edge" here refers to the edge of the second end battery 221 that is closer to the second solder strip 2220 among the two edges in the first direction. The "distance" here refers to the distance in the first direction. That is, z2 is the distance in the first direction from the second solder strip 2220 to the edge of the second end battery 221 that is closer to the second solder strip 2220 among the two edges in the first direction.

[0086] Specifically, z0 is the distance between the first end battery 211 and the second end battery 221. Here, "distance" refers to the distance in the first direction. That is, z0 is the distance between the first end battery 211 and the second end battery 221 in the first direction.

[0087] Specifically, The values ​​are, for example, 0.49 times, 0.45 times, 0.4 times, 0.3 times, 0.2 times, and 0.1 times z0. No specific limit is imposed here.

[0088] Please see Figure 1 In some embodiments, the back contact battery assembly 100 satisfies the following formula:

[0089] x = z1 = z2.

[0090] Thus, the distance between two adjacent third solder strips 214 in the first end battery 211, the distance from the first solder strip 2120 to the corresponding edge of the first end battery 211, and the distance from the second solder strip 2220 to the corresponding edge of the second end battery 221 are all equal, making the arrangement of the solder strips connecting the first end battery 211 and the second end battery 221 more regular, which helps to reduce the difficulty of the process and improve the manufacturing efficiency.

[0091] Specifically, in the first direction, the solder strips connected to the first end battery 211 can be evenly distributed with a first spacing, equally dividing the size of the first end battery 211 in the first direction. The solder strips connected to the second end battery 221 can be evenly distributed with a second spacing, equally dividing the size of the second end battery 221 in the first direction. The first spacing and the second spacing can be equal. Thus, in achieving... At the same time, the welding strips connecting the first end battery 211 and the second end battery 221 can be arranged in a more regular manner, which can further reduce the difficulty of the process and improve the manufacturing efficiency.

[0092] It is understood that the solder strips connected to the first end battery 211 can also be distributed at unequal intervals. x is the minimum value of the distance between two adjacent third solder strips 214 among the multiple third solder strips 214 distributed at unequal intervals. This minimum value x is equal to the distance z1 between two adjacent third solder strips 214 in the first end battery 211.

[0093] It is understood that the solder strips connected to the second end battery 221 may also be distributed at unequal intervals, and the distance z2 from the second solder strip 2220 to the corresponding edge of the second end battery 221 may be equal to the minimum value x of the distance between two adjacent third solder strips 214 in the first end battery 211.

[0094] In other embodiments, the solder strips connected to the first end battery 211 may be evenly spaced, but may not equally divide the size of the first end battery 211 in the first direction. For example, x is a constant value, but not equal to z1. In other embodiments, the solder strips connected to the second end battery 221 may be evenly spaced, but may not equally divide the size of the second end battery 221 in the first direction.

[0095] Please see Figure 2 and Figure 3 In some embodiments, the back contact battery assembly 100 includes:

[0096] The third busbar 31 and the fourth busbar 32 are respectively connected to the first interface 41 and the second interface 42 of the junction box 40;

[0097] The third string 23, which is adjacent to the second string 22, is located on the side of the second string 22 away from the first string 21. It includes several battery cells connected in series. The third string 23 includes a third end battery 231 and a third end solder strip 232. The third end solder strip 232 connects the third end battery 231 and the third busbar 31, including a fourth solder strip 2320 that is closest to the fourth busbar 32.

[0098] The second string 22 includes a fourth end battery 224 and a fourth end solder strip 225. The fourth end solder strip 225 connects the fourth end battery 224 and the fourth busbar 32, including a fifth solder strip 2250 closest to the third busbar 31.

[0099] The fourth solder strip 2320 is the solder strip adjacent to the outermost solder strip among the solder strips connected to the first end battery 211; the fifth solder strip 2250 is the solder strip adjacent to the outermost solder strip among the solder strips connected to the second end battery 221.

[0100] Thus, the adjacent solder strips of the busbars connected to the two adjacent junction boxes 40 are all secondary edge solder strips, which can provide enough space for setting the junction box 40, making it easy to install the junction box 40 between the third busbar 31 and the fourth busbar 32, which is beneficial to improving the production efficiency of photovoltaic modules.

[0101] Specifically, the third busbar 31 is connected to the first interface 41 of the junction box 40. The fourth busbar 32 is connected to the second interface 42 of the junction box 40. One of the first interface 41 and the second interface 42 of the junction box 40 is a positive interface, and the other is a negative interface.

[0102] Specifically, the third string 23 includes several solar cells connected in series. For example, the third string 23 includes 2, 3, 4 or other numbers of solar cells.

[0103] Specifically, the third string 23 includes a third end battery 231, a third end solder strip 232, and a third non-end solder strip 233. The third end solder strip 232 connects the third end battery 231 to the third busbar 31. The third non-end solder strip 233 connects the third end battery 231 to the battery cell adjacent to the third end battery 231. One of the third end solder strip 232 and the third non-end solder strip 233 is electrically connected to the positive grid line of the third end battery 231, and the other is electrically connected to the negative grid line of the third end battery 231.

[0104] Furthermore, the third end solder strip 232 includes the fourth solder strip 2320 closest to the fourth busbar 32. In other words, there are multiple third end solder strips 232, and the third end solder strip 232 closest to the fourth busbar 32 is the fourth solder strip 2320.

[0105] Furthermore, the fourth solder strip 2320 is the solder strip adjacent to the outermost solder strip among the solder strips connecting the third end battery 231. In other words, the fourth solder strip 2320 is the solder strip closest to the fourth busbar 32 and adjacent to the outermost solder strip among the third end solder strip 232 and the third non-end solder strip 233. That is, there is a third non-end solder strip 233 between the fourth solder strip 2320 and the fourth busbar 32, and this third non-end solder strip 233 is the solder strip located at the outermost edge and closest to the fourth busbar 32 among the solder strips connecting the third end battery 231.

[0106] Specifically, the second string 22 includes a fourth end battery 224, a fourth end solder strip 225, and a fourth non-end solder strip 226. The fourth end solder strip 225 connects the fourth end battery 224 to the fourth busbar 32. The fourth non-end solder strip 226 connects the fourth end battery 224 to the battery cell adjacent to the fourth end battery 224. One of the fourth end solder strip 225 and the fourth non-end solder strip 226 is electrically connected to the positive grid line of the fourth end battery 224, and the other is electrically connected to the negative grid line of the fourth end battery 224.

[0107] Furthermore, the fourth end solder strip 225 includes a fifth solder strip 2250 that is closest to the third busbar 31. In other words, there are multiple fourth end solder strips 225, and the fourth end solder strip 225 that is closest to the third busbar 31 is the fifth solder strip 2250.

[0108] Furthermore, the fifth solder strip 2250 is the solder strip adjacent to the outermost solder strip among the solder strips connecting the fourth end battery 224. In other words, the fifth solder strip 2250 is the solder strip closest to the third busbar 31 and adjacent to the outermost solder strip among the fourth end solder strip 225 and the fourth non-end solder strip 226. That is, there is a fourth non-end solder strip 226 between the fifth solder strip 2250 and the third busbar 31, and this fourth non-end solder strip 226 is the solder strip located at the outermost edge and closest to the third busbar 31 among the solder strips connecting the fourth end battery 224.

[0109] Please see Figure 2 and Figure 3 In some embodiments, the back contact battery assembly 100 satisfies the following formula:

[0110] E > 3D;

[0111] Where D is the minimum distance between two adjacent sixth welding strips 227, the sixth welding strip 227 is the welding strip connected to the third end battery 231 except for the fourth welding strip 2320 and the welding strip adjacent to the fourth welding strip 2320, and E is the distance between the fourth welding strip 2320 and the fifth welding strip 2250.

[0112] Thus, the distance E between the fourth solder strip 2320 and the fifth solder strip 2250 is more than three times the minimum distance between two adjacent sixth solder strips 227, making the distance E between the fourth solder strip 2320 and the fifth solder strip 2250 larger, thereby reserving enough space for the junction box 40.

[0113] Specifically, the "distance between two adjacent sixth weld strips 227" here refers to the distance in the first direction. That is, D is the minimum distance between two adjacent sixth weld strips 227 in the first direction.

[0114] It can be understood that if there are multiple sixth weld strips 227, then the distance between adjacent sixth weld strips 227 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 sixth weld strips 227 can be a fixed value or it can vary, and D can refer to the minimum distance between two adjacent sixth weld strips 227 whose distance varies.

[0115] Specifically, the "distance between the fourth solder strip 2320 and the fifth solder strip 2250" here refers to the distance in the first direction. That is, E is the distance between the fourth solder strip 2320 and the fifth solder strip 2250 in the first direction. Please note that when the distance between the fourth solder strip 2320 and the fifth solder strip 2250 in the first direction changes, E can refer to the minimum value of the distance between the fourth solder strip 2320 and the fifth solder strip 2250 in the first direction; it can also refer to the maximum value of the distance between the fourth solder strip 2320 and the fifth solder strip 2250 in the first direction.

[0116] Specifically, E can be 3.01D, 3.1D, 3.2D, 3.5D, 3.8D, 4D, 5D, 8D, etc.

[0117] Please see Figure 2 and Figure 3 In some embodiments, the distance S1 between the third end battery 231 and the fourth end battery 224 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 third end battery 231 and the fourth end battery 224 is within a suitable range. This avoids the third end battery 231 and the fourth end battery 224 being too close due to an excessively small S1, which would cause interference with the junction box 40. It also avoids the poor utilization of internal space and waste of internal space due to an excessively large S1.

[0118] Please note that "distance" here refers to the distance in the first direction. That is, S1 is the distance between the third end battery 231 and the fourth end battery 224 in the first direction.

[0119] 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 third-end battery 231 and the fourth-end battery 224, balancing interference avoidance with improved space utilization, resulting in a better overall effect. In one example, S1 is 1.6mm.

[0120] 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.

[0121] Please see Figure 2 and Figure 3 In some embodiments, the distance B between the first interface 41 and the second interface 42 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 41 and the second interface 42 is within a suitable range. It avoids the situation where B is too small, causing the two interfaces of the junction box 40 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 40. It also avoids the situation where B is too large, causing the junction box 40 to occupy too much space and wasting internal space of the components.

[0122] Please note that B can be the distance between the center point of the first interface 41 and the center point of the second interface 42. B can also be the distance from the edge of the first interface 41 closest to the second interface 42 to the edge of the second interface 42 closest to the first interface 41, such as... Figure 3 As shown.

[0123] 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 40 with space utilization, resulting in a better overall effect. In one example, B is 5.05mm.

[0124] 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.

[0125] Please see Figure 2 and Figure 3 In some embodiments, the distance D1 from the fourth solder strip 2320 to the corresponding edge of the third end battery 231 is 5mm-20mm. For example, it is 5mm, 6mm, 8mm, 10mm, 12mm, 15mm, 17mm, 19mm, or 20mm. This ensures that the distance D1 from the fourth solder strip 2320 to the corresponding edge of the third end battery 231 is within a suitable range. This avoids the fourth solder strip 2320 being too close to the corresponding edge of the third end battery 231, causing interference with the junction box 40 near that edge, if the distance is too small. It also avoids the effect of collecting current from the edge grid lines of the third end battery 231 being poor if D1 is too large.

[0126] Specifically, D1 is the distance from the fourth solder strip 2320 to the corresponding edge of the third end battery 231. Note that "corresponding edge" here refers to the edge of the third end battery 231 that is closer to the edge of the fourth solder strip 2320 among the two edges in the first direction. "Distance" here refers to the distance in the first direction. That is, D1 is the distance in the first direction from the fourth solder strip 2320 to the edge of the third end battery 231 that is closer to the edge of the fourth solder strip 2320 among the two edges in the first direction.

[0127] Specifically, D1 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 D1 between the fourth solder strip 2320 and the corresponding edge of the third end battery 231, balancing the avoidance of interference with ensuring current conduction, resulting in better overall performance. In one example, D1 is 11.715mm.

[0128] 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.

[0129] Please see Figure 2 and Figure 3 In some embodiments, the distance D2 from the fifth solder strip 2250 to the corresponding edge of the fourth end battery 224 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 fifth solder strip 2250 to the corresponding edge of the fourth end battery 224 is within a suitable range. This avoids the fifth solder strip 2250 being too close to the corresponding edge of the fourth end battery 224, causing interference with the junction box 40 near that edge, if the distance is too small. It also avoids the effect of collecting current from the edge grid lines of the fourth end battery 224 being poor if D2 is too large.

[0130] Specifically, D2 is the distance from the fifth solder strip 2250 to the corresponding edge of the fourth end battery 224. Note that "corresponding edge" here refers to the edge of the fourth end battery 224 that is closer to the edge of the fifth solder strip 2250 among the two edges in the first direction. "Distance" here refers to the distance in the first direction. That is, D2 is the distance in the first direction from the fifth solder strip 2250 to the edge of the fourth end battery 224 that is closer to the edge of the fifth solder strip 2250 among the two edges in the first direction.

[0131] 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 fifth solder strip 2250 and the corresponding edge of the fourth end battery 224, balancing the avoidance of interference with ensuring current conduction, resulting in better overall performance. In one example, D2 is 11.715mm.

[0132] 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.

[0133] Please see Figure 3 In some embodiments, the distance A1 between the third end battery 231 and the third busbar 31 is 2mm-4mm. For example, it is 2mm, 2.2mm, 2.5mm, 2.8mm, 3mm, 3.2mm, 3.5mm, 3.8mm, or 4mm.

[0134] This ensures that the distance A1 between the third end battery 231 and the third busbar 31 is within a suitable range. This avoids insufficient space left for the junction box 40 due to a small distance, or easy conduction between the third busbar 31 and the heterogeneous grid wires or solder strips of the third end battery 231. It also avoids wasting component space due to a large distance.

[0135] Preferably, the distance A1 between the third end battery 231 and the third busbar 31 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 third end battery 231 and the third busbar 31, balancing the installation of the junction box 40, reducing the risk of short circuits, and minimizing wasted space. In one example, the distance A1 between the third end battery 231 and the third busbar 31 is 3.1mm.

[0136] Please see Figure 3 In some embodiments, the distance A2 between the fourth end battery 224 and the fourth busbar 32 is 2mm-4mm. For example, it is 2mm, 2.2mm, 2.5mm, 2.8mm, 3mm, 3.2mm, 3.5mm, 3.8mm, or 4mm.

[0137] This ensures that the distance A2 between the fourth end battery 224 and the fourth busbar 32 is within a suitable range. This avoids insufficient space left for the junction box 40 due to a small distance, or easy conduction between the fourth busbar 32 and the irregular grid lines or solder strips of the fourth end battery 224. It also avoids wasting component space due to a large distance.

[0138] Preferably, the distance A2 between the fourth end battery 224 and the fourth busbar 32 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 fourth end battery 224 and the fourth busbar 32, balancing the installation of the junction box 40, reducing the risk of short circuits, and minimizing wasted space. In one example, the distance A2 between the fourth end battery 224 and the fourth busbar 32 is 3.1mm.

[0139] In some embodiments, the back contact battery assembly 100 includes a battery string, which includes a first string 21 and a second string 22. 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.

[0140] 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.

[0141] 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.

[0142] In some embodiments, the back contact battery assembly 100 includes a battery string, which includes a first string 21 and a second string 22. 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.

[0143] 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.

[0144] It is understandable that when the third and fourth pieces overlap, the distance between the third and fourth pieces is negative.

[0145] 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.

[0146] 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 third busbar 31, 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.

[0147] 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 21 and second string 22.

[0148] 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.

[0149] Please see Figure 3 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.

[0150] 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 40 due to the distance being too small, and can also avoid the waste of component space due to the distance being too large.

[0151] 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 40, 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.

[0152] Please see Figure 3 In some embodiments, the distance A4 between the second series structure 102 and the third busbar 31 is 2mm-4mm. For example, it is 2mm, 2.5mm, 3mm, 3.5mm, or 4mm.

[0153] This ensures that the distance A4 between the second series structure 102 and the third busbar 31 is within a suitable range, avoiding the difficulty of placing the busbar and junction box 40 due to excessive distance, and also avoiding the waste of component space due to excessive distance.

[0154] Preferably, the distance A4 between the second series structure 102 and the third busbar 31 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 third busbar 31, balancing the placement of the busbar and junction box 40 with component space utilization, resulting in better overall performance. In one example, the distance A4 between the second series structure 102 and the third busbar 31 is 3.1mm.

[0155] Please see Figure 4 and Figure 1 In some embodiments, the back contact battery assembly 100 includes a parallel busbar 30, which includes a third busbar 31 and a fourth busbar 32.

[0156] The first series structure 101 includes a plurality of first battery strings 20 connected in series and arranged along a first direction. The first battery strings 20 include a third string 23 and a second string 22. At least one first battery string 20 includes a first string end battery 201 and a first string end solder strip 202. The first string end battery 201 includes a third end battery 231 and a fourth end battery 224. The first string end solder strip 202 connects the first string end battery 201 and the parallel bus bar 30, and includes a third end solder strip 232 and a fourth end solder strip 225.

[0157] The second series structure 102 includes a plurality of second battery strings 50 connected in series and arranged along a first direction. At least one second battery string 50 includes a second string end battery 501 and a second string end solder strip 502. The second string end solder strip 502 connects the second string end battery 501 and the parallel bus bar 30.

[0158] The first end solder strip 202 is staggered from the second end solder strip 502.

[0159] In this way, the first string end solder strip 202 connected to the parallel busbar 30 is staggered with the second string end solder strip 502, which can avoid the large thickness caused by the overlap of the first string end solder strip 202 and the second string end solder strip 502, thereby reducing the risk of cell fragmentation during lamination.

[0160] Specifically, "the first end solder strip 202 and the second end solder strip 502 are staggered" means that there is a gap between the first end solder strip 202 and the second end solder strip 502, with no overlapping parts.

[0161] Please see Figure 4 In some embodiments, the minimum value w0 of the distance between the first end solder strip 202 and the second end solder strip 502 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.

[0162] This ensures that the minimum value of the distance w0 between the first end solder strip 202 and the second end solder strip 502 is within a suitable range, which can reduce the risk of overlap between the first end solder strip 202 and the second end solder strip 502 caused by the distance between them being too small.

[0163] It can be understood that there are multiple first-string end solder strips 202 and multiple second-string end solder strips 502, so the distance between the first-string end solder strip 202 and the second-string end solder strip 502 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 202 and second-string end solder strips 502 can be a fixed value or it can vary, and w0 can refer to the minimum distance between the first-string end solder strip 202 and the second-string end solder strip 502 when the distance varies.

[0164] Please see Figure 4 In some embodiments, the edges of the first terminal battery 201 and the second terminal battery 501 are offset in the width direction of the parallel busbar 30.

[0165] Thus, by staggering the first terminal battery 201 and the second terminal battery 501, the first terminal solder strip 202 connected to the first terminal battery 201 and the fourth terminal solder strip connected to the fourth terminal battery can be staggered.

[0166] Specifically, the edges of the first terminal battery 201 and the second terminal battery 501 are offset in the width direction of the parallel bus bar 30, meaning that the edges of the first terminal battery 201 and the fourth terminal battery do not overlap in the width direction of the parallel bus bar 30.

[0167] Please see Figure 4 In some embodiments, the solder strips connected to the first terminal battery 201 include a first edge solder strip 203 and a second edge solder strip 204, the first edge solder strip 203 and the second edge solder strip 204 being closest to the two edges of the first terminal battery 201 along the length of the parallel busbar 30; the solder strips connected to the second terminal battery 501 include a third edge solder strip 503 and a fourth edge solder strip 504, the third edge solder strip 503 and the fourth edge solder strip 504 being closest to the two edges of the second terminal battery 501 along the length of the parallel busbar 30.

[0168] The back contact battery assembly 100 satisfies the following formula:

[0169] 0 < w0 ≤ |w1 - w2|;

[0170] 0 < w0 ≤ |w3 - w4|;

[0171] Wherein, w0 is the minimum distance between the first end solder strip 202 and the second end solder strip 502; w1 is the distance between the first edge solder strip 203 and the corresponding edge of the first end battery 201; w2 is the distance between the second edge solder strip 204 and the corresponding edge of the first end battery 201; w3 is the distance between the third edge solder strip 503 and the corresponding edge of the second end battery 501; and w4 is the distance between the fourth edge solder strip 504 and the corresponding edge of the second end battery 501.

[0172] 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|.

[0173] Thus, the minimum value of the distance between the first end solder strip 202 and the second end solder strip 502 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 201 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 501 and their corresponding edges. This ensures that the minimum value of the distance between the first end solder strip 202 and the second end solder strip 502 is within a suitable range, which can avoid the waste of component space caused by the minimum value of the distance being too large.

[0174] Specifically, w1 is the distance between the first edge solder strip 203 and the corresponding edge of the first terminal battery 201. Note that "corresponding edge" here refers to the edge of the first terminal battery 201 that is closer to the first edge solder strip 203 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 203 to the edge of the first terminal battery 201 that is closer to the first edge solder strip 203 among the two edges in the first direction.

[0175] Specifically, w2 is the distance between the second edge solder strip 204 and the corresponding edge of the first terminal battery 201. Note that "corresponding edge" here refers to the edge of the first terminal battery 201 that is closer to the second edge solder strip 204 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 204 in the first direction to the edge of the first terminal battery 201 that is closer to the second edge solder strip 204 among the two edges in the first direction.

[0176] Specifically, w3 is the distance between the third edge solder strip 503 and the corresponding edge of the second terminal battery 501. Note that "corresponding edge" here refers to the edge of the second terminal battery 501 that is closer to the third edge solder strip 503 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 503 in the first direction to the edge of the second terminal battery 501 that is closer to the third edge solder strip 503 among the two edges in the first direction.

[0177] Specifically, w4 is the distance between the fourth edge solder strip 504 and the corresponding edge of the second terminal battery 501. Note that "corresponding edge" here refers to the edge of the second terminal battery 501 that is closer to the fourth edge solder strip 504 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 504 in the first direction to the edge of the second terminal battery 501 that is closer to the fourth edge solder strip 504 among the two edges in the first direction.

[0178] Please see Figure 4 In some embodiments, the back contact battery assembly 100 satisfies the following formula:

[0179] 0.25×|w1-w2|≤w0;

[0180] 0.25×|w3-w4|≤w0.

[0181] 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|.

[0182] Thus, the minimum value of the distance between the first end solder strip 202 and the second end solder strip 502 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 end battery 201 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 end battery 501 and their corresponding edges. This further optimizes the range of the minimum value of the distance between the first end solder strip 202 and the second end solder strip 502, and can avoid the risk of the first end solder strip 202 and the second end solder strip 502 overlapping due to the minimum value of this distance being too small.

[0183] Please see Figure 4 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.

[0184] In this way, the minimum value of the distance w0 between the first end solder strip 202 and the second end solder strip 502 is within a suitable range, which can reduce the risk of wasting space due to an excessively large distance between the first end solder strip 202 and the second end solder strip 502.

[0185] 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 202 and the second end solder strip 502, avoiding solder strip overlap and wasted space, resulting in better overall performance. In one example, w0 is 0.5mm.

[0186] Please see Figure 4 In some embodiments, w1 is 0.5mm-5mm. For example, it is 0.5mm, 0.8mm, 0.965mm, 1mm, 2mm, 3mm, 4mm, or 5mm.

[0187] In this way, the distance between the first edge solder strip 203 and the corresponding edge of the first string battery 201 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.

[0188] Please see Figure 4 In some embodiments, w2 is greater than w1, and is 0.5 mm to mm. For example, it is 0.5 mm, 0.8 mm, 1 mm, 3 mm, 4 mm, 4.805 mm, 6 mm, 9 mm, or mm.

[0189] This ensures that the distance between the second edge solder strip 204 and the corresponding edge of the first string battery 201 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.

[0190] Please see Figure 4 In some embodiments, w3 is 0.5mm-5mm. For example, it is 0.5mm, 0.8mm, 0.965mm, 1mm, 2mm, 3mm, 4mm, or 5mm.

[0191] This ensures that the distance between the third edge solder strip 503 and the corresponding edge of the second string battery 501 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.

[0192] Please see Figure 4 In some embodiments, w4 is greater than w3, and is 0.5 mm to mm. For example, it is 0.5 mm, 0.8 mm, 1 mm, 3 mm, 4 mm, 4.805 mm, 6 mm, 9 mm, or mm.

[0193] This ensures that the distance between the fourth edge solder strip 504 and the corresponding edge of the second string terminal battery 501 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.

[0194] 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 solar cell, as well as between the photovoltaic glass and adjacent 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.

[0195] Photovoltaic glass can be applied to the encapsulating film on the front of solar cells. 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 cells while minimizing impact on their efficiency. Simultaneously, the encapsulating film bonds the photovoltaic glass and the solar cells together, providing sealing, insulation, and waterproofing / moisture protection for the solar cells.

[0196] The backsheet can be attached to the encapsulant 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, and aluminum alloy TPT composite encapsulant film, etc., with specific choices depending on the circumstances. The backsheet, solar cell, encapsulant 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.

[0197] The photovoltaic system of this application embodiment includes the back contact battery module 100 described above.

[0198] In the photovoltaic system of this application embodiment, since the adjacent first solder strips 2120 and second solder strips 2220 connected to two adjacent busbars located at the end region of the module are both the outermost solder strips, and the spacing between them is greater than twice the spacing between two adjacent solder strips in the first end cell 211 excluding the first solder strip 2120 and the solder strip adjacent to the first solder strip 2120, the spacing between the first solder strip 2120 and the second solder strip 2220 can be larger, thereby reducing the risk of leakage caused by the small spacing between the first solder strip 2120 and the second solder strip 2220.

[0199] In this embodiment, the photovoltaic system can be applied in photovoltaic power plants, such as ground-mounted power plants, rooftop power plants, and floating power plants. It can also be applied to equipment or devices that utilize solar energy to generate electricity, such as user solar power supplies, solar streetlights, solar cars, and solar buildings. Of course, it is understood that the application scenarios of the photovoltaic system are not limited to these; that is, the photovoltaic system can be applied in all fields that require solar energy to generate electricity. Taking a photovoltaic power generation system network as an example, the photovoltaic system may include a photovoltaic array, a combiner box, and an inverter. The photovoltaic array may be an array combination of multiple battery modules; for example, multiple battery modules can form multiple photovoltaic arrays. The photovoltaic array is connected to the combiner box, which can collect the current generated by the photovoltaic array. The collected current flows through the inverter and is converted into AC power required by the mains power grid before being connected to the mains power grid to achieve solar power supply.

[0200] 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.

[0201] 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 located in the end region of the back contact battery assembly; 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 to which the first end battery is connected; the second solder strip is the outermost solder strip among the solder strips to which the second end battery is connected. The back contact battery assembly satisfies the following formula: y > 2x; Where x 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 y 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, x is 2mm-10mm.

3. The back contact battery assembly according to claim 1, characterized in that, y is greater than 4mm.

4. The back contact battery assembly according to claim 3, characterized in that, y is 5mm-20mm.

5. The back contact battery assembly according to claim 1, characterized in that, The first string includes an even number of battery cells; And / or, the number of battery cells included in the second string is even.

6. The back contact battery assembly according to claim 1, characterized in that, The back contact battery assembly satisfies the following formula: Where z1 is the distance from the first solder strip to the corresponding edge of the first end battery, z2 is the distance from the second solder strip to the corresponding edge of the second end battery, and z0 is the distance between the first end battery and the second end battery.

7. The back contact battery assembly according to claim 6, characterized in that, The back contact battery assembly satisfies the following formula: x = z1 = z2.

8. The back contact battery assembly according to claim 1, characterized in that, The back contact battery assembly includes: The third and fourth busbars are connected to the first and second interfaces of the junction box, respectively; The third string adjacent to the second string is located on the side of the second string away from the first string, and includes several battery cells connected in series. The third string includes a third end battery and a third end solder strip. The third end solder strip connects the third end battery to the third busbar, including a fourth solder strip closest to the fourth busbar. The second string includes a fourth end battery and a fourth end solder strip, the fourth end solder strip connecting the fourth end battery to the fourth busbar, including a fifth solder strip closest to the third busbar; The fourth solder strip is the solder strip adjacent to the outermost solder strip among the solder strips connected to the first end battery; the fifth solder strip is the solder strip adjacent to the outermost solder strip among the solder strips connected to the second end battery.

9. The back contact battery assembly according to claim 8, characterized in that, The back contact battery assembly satisfies the following formula: E > 3D; Where D is the minimum distance between two adjacent sixth solder strips, the sixth solder strip is the solder strip connected to the third end battery excluding the fourth solder strip and the solder strip adjacent to the fourth solder strip, and E is the distance between the fourth solder strip and the fifth solder strip.

10. The back contact battery assembly according to claim 8, characterized in that, The distance between the third end battery and the fourth end battery is 0.5mm-15mm.

11. The back contact battery assembly according to claim 8, characterized in that, The distance between the first interface and the second interface is 3mm-15mm.

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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