Back contact battery assembly and photovoltaic system

Abstract

The utility model is applicable to the field of photovoltaic technology, and provides a back contact battery assembly and a photovoltaic system, the back contact battery assembly comprises a first battery string, a second battery string and a junction box, the first battery string and the second battery string are arranged at an interval along a first direction at a first preset distance D1, according to the scheme, the first welding strips, closest to the second edge, on the first battery string are arranged at intervals from the second edge by the second preset distance D2, and the second welding strips, closest to the third edge, on the second battery string are arranged at intervals from the third edge by the third preset distance D3. And enough space is formed between the first battery string and the second battery string for mounting the junction box.

Description

Technical Field

[0001] This application belongs to the technical field of photovoltaics, and particularly relates to a back-contact battery module and a photovoltaic system. Background Art

[0002] In related technologies, since the existing solder tapes are uniformly arranged on the battery string of the back-contact battery module, the solder tapes at the edge of the battery string are relatively close to the edge of the battery string, so the distance between two groups of battery strings is small and it is difficult to install the junction box. Therefore, how to optimize the installation of the junction box is a problem to be solved. Summary of the Utility Model

[0003] This application provides a back-contact battery module and a photovoltaic system, aiming to solve the problem that it is difficult to install the junction box due to the small distance between two groups of battery strings.

[0004] This application is implemented as follows. A back-contact battery module includes:

[0005] A first battery string, the first battery string having a first edge and a second edge oppositely arranged in the first direction;

[0006] A second battery string, the second battery string having a third edge and a fourth edge oppositely arranged in the first direction, the first battery string and the second battery string being spaced apart by a first preset distance D1 along the first direction, and the second edge and the third edge being close to each other;

[0007] A plurality of first solder tapes, the plurality of first solder tapes being spaced apart along the first direction on the first battery string, the plurality of first solder tapes having the same polarity, and the plurality of first solder tapes being commonly connected to a first bus bar;

[0008] A plurality of second solder tapes, the plurality of second solder tapes being spaced apart along the first direction on the second battery string, the plurality of second solder tapes having the same polarity, and the plurality of second solder tapes being commonly connected to a second bus bar;

[0009] The distance between the solder tape closest to the second edge on the first battery string and the second edge in the first direction is a second preset distance D2, and the solder tape closest to the second edge on the first battery string is the first solder tape;

[0010] The distance between the solder tape closest to the third edge on the second battery string and the third edge in the first direction is a third preset distance D3, and the solder tape closest to the third edge on the second battery string is the second solder tape;

[0011] Junction box, the junction box has a first terminal and a second terminal, the first terminal and the second terminal are spaced apart by a fourth preset distance B, the first bus bar is connected to the first terminal, and the second bus bar is connected to the second terminal; wherein,

[0012] The second preset distance D2 satisfies the following relationship: D2 = B + Δ1 + Δ2 - D1 - D3; the third preset distance D3 satisfies the following relationship: D3 = B + Δ1 + Δ2 - D1 - D2; wherein the range of the first preset value Δ1 is 3 - 15 mm, and the range of the second preset value Δ2 is 3 - 15 mm.

[0013] Optionally, the absolute value of the difference between the second preset distance D2 and the third preset distance D3 is greater than or equal to 0 and less than or equal to 2.5 mm.

[0014] Optionally, the range of the second preset distance D2 is 5 - 15 mm, and the range of the third preset distance D3 is 5 - 15 mm.

[0015] Optionally, the first battery string and the second battery string are of the same type of battery string.

[0016] Optionally, the junction box is arranged between the first battery string and the second battery string, the junction box has opposite first and second ends in the first direction, the distance between the second edge of the first battery string and the first end in the first direction is the first distance, and the distance between the third edge of the second battery string and the second end in the first direction is the second distance. The absolute value of the difference between the first distance and the second distance is greater than or equal to 0 and less than or equal to 3 mm, and the first preset value △1 is equal to the second preset value △2.

[0017] Optionally, the junction box is arranged between the first battery string and the second battery string, the junction box has opposite first and second ends in the first direction, the distance between the second edge of the first battery string and the first end in the first direction is the first distance, and the distance between the third edge of the second battery string and the second end in the first direction is the second distance. The first distance and the second distance are not equal, and the first preset value Δ1 and the second preset value Δ2 are not equal.

[0018] Optionally, it further includes a plurality of third solder tapes, and the plurality of third solder tapes and the plurality of first solder tapes are alternately arranged at intervals along the first direction on the first battery string, and the third solder tapes and the first solder tapes have opposite polarities.

[0019] Optionally, the plurality of third solder tapes and the plurality of first solder tapes are arranged alternately at equal intervals along the first direction on the first battery string.

[0020] Optionally, the distance between the nth first solder strip and the nth third solder strip on the first battery string is a third distance, and the distance between the nth third solder strip and the (n + 1)th first solder strip on the first battery string is a fourth distance. The third distance is different from the fourth distance, where n is a positive integer.

[0021] Optionally, adjacent ones of the plurality of first solder strips are spaced apart at a fifth preset distance L1, and adjacent ones of the plurality of third solder strips are spaced apart at a sixth preset distance L2. The absolute value of the difference between the fifth preset distance L1 and the sixth preset distance L2 is greater than or equal to 0 and less than or equal to 2.5 mm.

[0022] Optionally, the range of the third distance is greater than 0 and less than or equal to 2 mm.

[0023] Optionally, it further includes a plurality of fourth solder strips. The plurality of second solder strips and the plurality of fourth solder strips are alternately spaced along the first direction on the second battery string, and the second solder strip and the fourth solder strip have opposite polarities.

[0024] Optionally, the plurality of fourth solder strips and the plurality of second solder strips are alternately arranged at equal intervals along the first direction on the second battery string.

[0025] Optionally, the distance between the nth second solder strip and the nth fourth solder strip on the second battery string is a fifth distance, and the distance between the nth fourth solder strip and the (n + 1)th second solder strip on the second battery string is a sixth distance. The fifth distance is different from the sixth distance, where n is a positive integer.

[0026] Optionally, the range of the fifth distance is greater than 0 and less than or equal to 2 mm.

[0027] Optionally, adjacent ones of the plurality of second solder strips are spaced apart at a seventh preset distance L3, and adjacent ones of the plurality of fourth solder strips are spaced apart at an eighth preset distance L4. The absolute value of the difference between the seventh preset distance L3 and the eighth preset distance L4 is greater than or equal to 0 and less than or equal to 2.5 mm.

[0028] Beneficial effects achieved by this application: In the solution of this application, the solder tape closest to the second edge on the first battery string is spaced from the second edge at a second preset distance D2, and the solder tape closest to the third edge on the second battery string is spaced from the third edge at a third preset distance D3. The second preset distance D2 satisfies the following relationship: D2 = B + Δ1 + Δ2 - D1 - D3; the third preset distance D3 satisfies the following relationship: D3 = B + Δ1 + Δ2 - D1 - D2. Through the above arrangement, there is sufficient space between the first battery string and the second battery string for installing the junction box. And in the solution of this application, since the solder tape closest to the second edge in the first battery string and the solder tape closest to the third edge in the second battery string are connected to the junction box through the bus bar, the carriers at the edge of the battery string can be effectively collected, thereby improving the power generation efficiency of the back-contact battery module.

[0029] A photovoltaic system includes the above-mentioned back-contact battery module. The technical effects of this application are the same as those of the above-mentioned back-contact battery module, and will not be elaborated here. Description of the Drawings

[0030] Figure 1 is a schematic structural diagram of an embodiment of the back-contact battery module provided by the present application;

[0031] Figure 2 is Figure 1 an enlarged view of the structure at A of

[0032] Figure 3 is a schematic structural diagram of another embodiment of the back-contact battery module provided by the present application.

[0033] Description of the Reference Numerals:

[0034] 100, back-contact battery module; 101, first battery cell; 103, first edge; 104, second edge; 10, first battery string; 20, second battery string; 201, second battery cell; 203, third edge; 204, fourth edge; 30, first solder tape; 40, second solder tape; 50, third solder tape; 60, fourth solder tape; 70, junction box; 701, first connection terminal; 702, second connection terminal; 80, first bus bar; 90, second bus bar. Detailed Embodiments

[0035] In order to make the objectives, technical solutions and advantages of the present application more clear and understandable, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions from beginning to end. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present application, and should not be construed as a limitation to the present application. In addition, it should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0036] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "left", "right", "horizontal", "top", "bottom", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0037] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the described features. In the description of the present application, the meaning of "a plurality" is two or more unless otherwise specifically defined.

[0038] In the description of the present application, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected" and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection or an integral connection; it may be a mechanical connection, an electrical connection or a connection that can communicate with each other; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0039] In the present application, unless otherwise clearly specified and defined, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features therebetween. Moreover, the first feature being "above", "over" and "on" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0040] The following disclosure provides many different embodiments or examples for implementing different structures of the present application. To simplify the disclosure of the present application, the components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the present application. In addition, the present application may repeat reference numerals and / or reference letters in different examples. Such repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present application provides examples of various specific processes and materials, but those of ordinary skill in the art can realize the application of other processes and / or the use of other materials.

[0041] The photovoltaic system in the embodiments of the present application may include the back-contact battery assembly in the embodiments of the present application. The back-contact battery assembly 100 in the embodiments of the present application may include several battery strings in the embodiments of the present application.

[0042] Please refer to Figure 1 , a back-contact battery assembly 100, including a first battery string 10, a second battery string 20, a plurality of first solder tapes 30, a plurality of second solder tapes 40, a plurality of third solder tapes 50, a plurality of fourth solder tapes 60, and a junction box 70.

[0043] In the embodiments of the present application, a plurality of first solder tapes 30 and a plurality of third solder tapes 50 are arranged at intervals and alternately in the first direction on the first battery string 10, and a plurality of second solder tapes 40 and a plurality of fourth solder tapes 60 are arranged at intervals and alternately in the first direction on the second battery string 20.

[0044] Among them, a plurality of first solar cells 101 are arranged at intervals in the second direction. A plurality of first solder tapes 30 and a plurality of third solder tapes 50 extend along the second direction and connect the plurality of first solar cells 101 to form the first battery string 10. A plurality of second solar cells 201 are arranged at intervals in the second direction. A plurality of second solder tapes 40 and a plurality of fourth solder tapes 60 extend along the second direction and connect the plurality of second solar cells 201 to form the second battery string 20.

[0045] As Figure 1 shown, in the embodiments of the present application, the first direction is the horizontal direction, and the first direction is also the width direction of the first battery string or the second battery string. The second direction is the vertical direction, and the second direction is also the length direction of the first battery string or the second battery string.

[0046] In the related art, since the existing solder tapes are uniformly arranged on the battery strings of the back-contact battery assembly, the solder tapes at the edge of the battery string are relatively close to the edge of the battery string. In this way, the distance between the two groups of battery strings is small and it is difficult to install the junction box. Therefore, how to optimize the installation of the junction box is a problem that needs to be solved.

[0047] The first battery string 10 has a first edge 103 and a second edge 104 that are oppositely arranged in the first direction; the second battery string 20 has a third edge 203 and a fourth edge 204 that are oppositely arranged in the first direction. The first battery string 10 and the second battery string 20 are arranged at an interval of a first preset distance D1 in the first direction, and the second edge 104 and the third edge 203 are close to each other; it can be understood that in the embodiments of the present application, the first battery string 10 and the second battery string 20 are arranged at an interval of a first preset distance D1 in the first direction, which means that the second edge 104 and the third edge 203 are arranged at an interval of a first preset distance D1.

[0048] A plurality of first solder tapes 30 are arranged at intervals in the first direction on the first battery string 10. The plurality of first solder tapes 30 have the same polarity, and the plurality of first solder tapes 30 are commonly connected to the first bus bar 80; the first bus bar 80 is used to collect the carriers on the plurality of first solder tapes 30 and lead them out.

[0049] A plurality of second solder tapes 40 are arranged at intervals in the first direction on the second battery string 20. The plurality of second solder tapes 40 have the same polarity, and the plurality of second solder tapes 40 are commonly connected to the second bus bar 90; the second bus bar 90 is used to collect the carriers on the plurality of second solder tapes 40 and lead them out.

[0050] The distance between the solder tape closest to the second edge 104 on the first battery string 10 and the second edge 104 in the first direction is a second preset distance D2. The solder tape closest to the second edge 104 on the first battery string 10 is the first solder tape 30; it can be understood that that is to say, the minimum distance from the plurality of first solder tapes 30 to the second edge 104 is the second preset distance D2.

[0051] The distance between the solder tape closest to the third edge 203 on the second battery string 20 and the third edge 203 in the first direction is a third preset distance D3. The solder tape closest to the third edge 203 on the second battery string 20 is the second solder tape 40; that is to say, the minimum distance from the plurality of second solder tapes 40 to the third edge 203 is the third preset distance D3.

[0052] The junction box 70 has a first terminal 701 and a second terminal 702. The first terminal 701 and the second terminal 702 are arranged at an interval of a fourth preset distance B. The first bus bar 80 is connected to the first terminal 701, and the second bus bar 90 is connected to the second terminal 702; it can be understood that the polarities of the first terminal 701 and the second terminal 702 are opposite, where

[0053] The second preset distance D2 satisfies the following relationship: D2 = B + Δ1 + Δ2 - D1 - D3; the third preset distance D3 satisfies the following relationship: D3 = B + Δ1 + Δ2 - D1 - D2; where the range of the first preset value Δ1 is 3 - 15 mm, and the range of the second preset value Δ2 is 3 - 15 mm.

[0054] Furthermore, the range of the second preset distance D2 is 5 - 15 mm, and the range of the third preset distance D3 is 5 - 15 mm. Setting the second preset distance D2 and the third preset distance D3 within this range can adapt to most types of junction boxes on the market, and will not cause much loss of carriers at the edge of the battery string, ensuring the power generation efficiency of the back-contact battery module.

[0055] Specifically, in such an embodiment, the second preset distance D2 can be 5 mm, 6 mm, 7.2 mm, 7.4 mm, 7.6 mm, 7.8 mm, 8 mm, 8.2 mm, 8.4 mm, 8.6 mm, 8.8 mm, 10 mm, 15 mm or any value between 5 mm - 15 mm, and specific values are not limited here. The third preset distance D3 can be 5 mm, 6 mm, 7.2 mm, 7.4 mm, 7.6 mm, 7.8 mm, 8 mm, 8.2 mm, 8.4 mm, 8.6 mm, 8.8 mm, 10 mm, 15 mm or any value between 5 mm - 15 mm, and specific values are not limited here.

[0056] Preferably, the range of the second preset distance D2 is 7.2 - 10 mm, and the range of the third preset distance D3 is 7.2 - 10 mm. In such an embodiment, the second preset distance D2 can be 7.2 mm, 7.4 mm, 7.6 mm, 7.8 mm, 8 mm, 8.2 mm, 8.4 mm, 8.6 mm, 8.8 mm, 10 mm or any value between 7.2 mm - 10 mm, and specific values are not limited here. The third preset distance D3 can be 7.2 mm, 7.4 mm, 7.6 mm, 7.8 mm, 8 mm, 8.2 mm, 8.4 mm, 8.6 mm, 8.8 mm, 10 mm or any value between 7.2 mm - 10 mm, and specific values are not limited here.

[0057] The absolute value of the difference between the second preset distance D2 and the third preset distance D3 is greater than or equal to 0 and less than or equal to 2.5 mm. In the embodiments of the present application, the second preset distance D2 and the third preset distance D3 are theoretically equal. However, due to process reasons, the absolute value of the difference between the second preset distance D2 and the third preset distance D3 within the range of [0, 2.5] can also be regarded as the second preset distance D2 and the third preset distance D3 being equal, so that the solder tapes of the first battery string and the second battery string can be arranged consistently, simplifying the production process.

[0058] In addition, in the prior art, in order to connect the battery string to the junction box, it is usually necessary to produce two types of battery strings (which can also be called string A and string B) to leave enough space for installing the junction box. However, in this production method, on the one hand, the production process of the AB battery strings is relatively complex, which affects the production capacity of the components. On the other hand, when one type of battery string is unqualified, the other type of battery string cannot proceed to the next process even if it is qualified. For example, when a large number of string A are unqualified, a corresponding number of string B will be affected and cannot be connected in series with string B in time, resulting in product backlog.

[0059] In some embodiments, the first battery string and the second battery string are of the same type. The battery strings of the same type referred to in this application mean that the electrode arrangement methods of the battery strings are the same. Further, the second battery string can be obtained by rotating the first battery string by 180 degrees. This can solve the problem in the prior art that two types of battery strings need to be manufactured, simplify the production process, and reduce product backlog.

[0060] It can be understood that the battery strings of the same type are relative to string A and string B in the prior art. That is to say, in some embodiments, the first battery string and the second battery string are the same type of battery string, rather than string A and string B in the prior art.

[0061] Further, the first solder tape 30 is commonly connected to the first bus bar 80, the second solder tape 40 is commonly connected to the second bus bar 90. The junction box 70 has a first connection hole and a second connection hole. A first connection head is arranged in the first connection hole, and a second connection head is arranged in the second connection hole. The first bus bar 80 has a first end and a second end arranged oppositely, and the second bus bar 90 has a third end and a fourth end arranged oppositely. The second end is connected to the first connection head, and the third end is connected to the second connection head. The second end and the third end need to be bent in a direction away from the plane where the battery cells are located, so that the first connection hole on the junction box 70 and the second end can be respectively plugged and connected with the second connection hole and the third end on the junction box.

[0062] In order to ensure that there is enough distance between the second end of the first bus bar 80 and the third end of the second bus bar 90 for installing the junction box, in some embodiments, the minimum distance from the second edge among the plurality of first solder tapes 30 and the minimum distance from the third edge among the plurality of second solder tapes 40 can be set to a larger value, so that there is enough space between the first solder tape 30 at the edge of the first battery string 10 and the second solder tape 40 at the edge of the second battery string 20 for installing the junction box. However, this is likely to cause the values of the second preset distance D2 and the third preset distance D3 to be set disorderly and randomly, resulting in the loss of carriers at the edge of the battery string.

[0063] In other embodiments, the bus bars arranged in the first direction from the second edge 104 to the first edge 103 are successively defined as the first bus bar of string a, the second bus bar of string a, the third bus bar of string a, the fourth bus bar of string a, and so on. The bus bars arranged in the first direction from the third edge 203 to the fourth edge 204 are successively defined as the first bus bar of string b, the second bus bar of string b, the third bus bar of string b, the fourth bus bar of string b, and so on. The second bus bar of string a can be connected to the first bus bar, and the second bus bar of string b can be connected to the second bus bar. The first bus bar of string a is not connected to the first bus bar, and the first bus bar of string b is not connected to the second bus bar. In this way, there is also enough space between the second bus bar of string a and the second bus bar of string b to install the junction box. However, this setting method will, on the one hand, lose the carriers collected by the first bus bar of string a and the first bus bar of string b, reducing the power generation efficiency of the back-contact battery module.

[0064] In the solution of the present application, the bus bar on the first battery string 10 closest to the second edge 104 is spaced from the second edge 104 by a second preset distance D2, and the bus bar on the second battery string 20 closest to the third edge 203 is spaced from the third edge 203 by a third preset distance D3. The second preset distance D2 satisfies the following relationship: D2 = B + Δ1 + Δ2 - D1 - D3; the third preset distance D3 satisfies the following relationship: D3 = B + Δ1 + Δ2 - D1 - D2; where the range of the first preset value Δ1 is 3 - 15 mm, and the range of the second preset value Δ2 is 3 - 15 mm. By setting in the above manner and associating the settings of the second preset distance D2 and the third preset distance D3 with the size data of the junction box, junction boxes of different types can be adapted. Thus, the laying of the bus bars can be carried out in advance. Moreover, in this setting method, not only is there enough space between the first battery string 10 and the second battery string 20 to install the junction box, realizing the carrier confluence of the bus bars at the outermost edge of the battery string, but also the numerical setting ranges of the second preset distance D2 and the third preset distance D3 can be controlled, maximizing the collection of the carriers at the edge of the battery string and avoiding the loss of the carriers at the edge of the battery string caused by the random and disorderly setting of the numerical values of the second preset distance D2 and the third preset distance D3.

[0065] In the solution of the present application, since the bus bar on the first battery string 10 closest to the second edge 104 and the bus bar on the second battery string 20 closest to the third edge 203 are connected to the junction box through the bus bar, the carriers at the edge of the battery string can be effectively collected, thereby improving the power generation efficiency of the back-contact battery module.

[0066] In some embodiments, the junction box 70 is disposed between the first battery string 10 and the second battery string 20. The junction box has opposite first end 703 and second end 704 in a first direction. The distance between the second edge of the first battery string and the first end in the first direction is a first distance, and the distance between the third edge of the second battery string and the second end in the first direction is a second distance. The absolute value of the difference between the first distance and the second distance is greater than or equal to 0 and less than or equal to 3 mm. The first preset value △1 and the second preset value △2 are equal. In the embodiments of the present application, theoretically, the distance between the second edge 104 of the first battery string 10 and one end of the junction box 70 in the first direction is equal to the distance between the third edge 203 of the second battery string 20 and the other end of the junction box 70 in the first direction. However, due to process reasons, the absolute value of the difference between the distance between the second edge 104 of the first battery string 10 and one end of the junction box 70 in the first direction and the distance between the third edge 203 of the second battery string 20 and the other end of the junction box 70 in the first direction is within the range of [0, 3], and it can also be regarded as the distance between the second edge 104 of the first battery string 10 and one end of the junction box 70 in the first direction being equal to the distance between the third edge 203 of the second battery string 20 and the other end of the junction box 70 in the first direction.

[0067] In other embodiments, the junction box 70 is disposed between the first battery string 10 and the second battery string 20. The junction box has opposite first end 703 and second end 704 in a first direction. The distance between the second edge of the first battery string and the first end in the first direction is a first distance, and the distance between the third edge of the second battery string and the second end in the first direction is a second distance. The first distance and the second distance are not equal, and the first preset value Δ1 and the second preset value Δ2 are not equal.

[0068] Exemplarily, the first distance and the second distance are not equal, which can be understood as the absolute value of the difference between the first distance and the second distance being greater than 3 mm.

[0069] It can be seen from this that the numerical settings of the first preset value and the second preset value are related to the position setting of the junction box 70. Usually, the bending part of the bus bar is an arc curve. In fact, the first preset value is associated with the margin value required when the first bus bar 80 is bent, and the second preset value is associated with the margin value required when the second bus bar 90 is bent. When the junction box 70 is located at the middle position between the second edge 104 and the third edge 203, the bending degrees of the first bus bar 80 and the second bus bar 90 are the same, and the first preset value and the second preset value are equal. When the junction box 70 is not at the middle position between the second edge 104 and the third edge 203, due to the different bending radians of the first bus bar 80 and the second bus bar 90, the first preset value and the second preset value are different.

[0070] In the embodiments of the present application, the range of the first preset value Δ1 is 3 - 15 mm, and the range of the second preset value Δ2 is 3 - 15 mm. Preferably, the first preset value Δ1 and the second preset value Δ2 are 3 mm, so as to minimize the numerical settings of the second preset distance and the third preset distance, thereby enabling better collection of the edge carriers of the battery string.

[0071] Of course, in other embodiments, the first preset value Δ1 and the second preset value Δ2 can also be less than 3 mm, or even 0 mm, to achieve a right-angle bending effect, and the present application does not limit this. This can further reduce the numerical settings of the second preset distance and the third preset distance, thereby better collecting the carriers at the edge of the battery string.

[0072] As Figure 3 shown, in some embodiments, on the first battery string 10, a plurality of third solder tapes 50 and a plurality of first solder tapes 30 are alternately arranged at intervals along a first direction on the first battery string 10, and the third solder tapes 50 and the first solder tapes 30 have opposite polarities. Further, a plurality of third solder tapes 50 and a plurality of first solder tapes 30 are alternately arranged at equal intervals along the first direction on the first battery string 10. In this way, a plurality of first solder tapes 30 and a plurality of third solder tapes 50 are evenly distributed on the first battery string 10, and the uniform solder tape layout helps to reduce the resistance inside the battery cell. In a photovoltaic module, current needs to be transmitted through the solder tapes, and the equal-distance solder tape layout helps to optimize the resistance characteristics, improve the current transmission efficiency, and the carriers at the first edge of the first battery string can be effectively collected.

[0073] As Figure 1 shown, starting from the first edge 103 and counting towards the second edge 104, the distance between the nth first solder tape 30 and the nth third solder tape 50 on the first battery string 10 is the third distance, and the distance between the nth third solder tape 50 and the (n + 1)th first solder tape 30 on the first battery string 10 is the fourth distance. The third distance is different from the fourth distance, and n is a positive integer. Compared with the traditional uniform and equal-distance distribution method of solder tapes, with the same size of the battery cell and the same number of solder tapes, the distance between adjacent two first solder tapes 30 and the distance between adjacent two third solder tapes 50 can be relatively close, thereby shortening the transmission path of the carriers, and further improving the efficiency of the battery cell.

[0074] In some embodiments, the range of the third distance is greater than 0 and less than or equal to 2 mm, and the third distance is not equal to the fourth distance. By setting the range of the third distance as above, on the one hand, the transmission distance of the carriers between the first solder tape 30 and the third solder tape 50 can be reduced, and on the other hand, the distance between adjacent first solder tapes 30 and adjacent third solder tapes 50 can also be relatively small, thereby shortening the overall carrier transmission distance of the battery cell and improving the power generation efficiency of the back-contact battery module.

[0075] As Figure 2 shown, in some embodiments, the adjacent ones of the plurality of first solder tapes 30 are spaced apart by a fifth preset distance L1, and the adjacent ones of the plurality of third solder tapes 50 are spaced apart by a sixth preset distance L2. The absolute value of the difference between the fifth preset distance L1 and the sixth preset distance L2 is greater than or equal to 0 and less than or equal to 2.5 mm. In the embodiments of the present application, the fifth preset distance L1 and the sixth preset distance L2 are theoretically equal. However, due to process reasons, the absolute value of the difference between the fifth preset distance L1 and the sixth preset distance L2 is within the range of [0, 2.5], and it can also be regarded as the fifth preset distance L1 and the sixth preset distance L2 being equal. Through such a design, the uniform distribution of current in the battery cell can be improved, which helps to reduce the heat concentration phenomenon caused by uneven current distribution, thereby improving the overall efficiency and stability of the battery cell. In the production process, the production process can also be simplified and the production efficiency can be improved.

[0076] As Figure 3 shown, in some embodiments, the plurality of second solder tapes 40 and the plurality of fourth solder tapes 60 are alternately arranged at intervals along a first direction on the second battery string 20, and the second solder tapes 40 and the fourth solder tapes 60 have opposite polarities. Further, the plurality of fourth solder tapes 60 and the plurality of second solder tapes 40 are alternately arranged at equal intervals along the first direction on the second battery string 20. In this way, the plurality of second solder tapes 40 and the plurality of fourth solder tapes 60 are evenly distributed on the second battery string 20, and the uniform solder tape layout helps to reduce the resistance inside the battery cell. In a photovoltaic module, current needs to be transmitted through the solder tapes, and the equal-distance solder tape layout helps to optimize the resistance characteristics, improve the current transmission efficiency, and the carriers at the fourth edge of the second battery string 20 can be effectively collected.

[0077] As Figure 1 shown, in some embodiments, starting from the third edge 203 to the fourth edge 204, the distance between the nth second solder tape and the nth fourth solder tape on the second battery string 20 is the fifth distance, and the distance between the nth fourth solder tape and the (n + 1)th second solder tape on the second battery string 20 is the sixth distance. The fifth distance is different from the sixth distance, and n is a positive integer. Compared with the traditional uniform and equal-distance distribution method of solder tapes, when the size of the battery cell is the same and the number of solder tapes is the same, the distance between adjacent two second solder tapes 40 and the distance between adjacent two fourth solder tapes 60 can be relatively close, thereby shortening the carrier transmission path and further improving the efficiency of the battery cell.

[0078] In some embodiments, the range of the fifth distance is greater than 0 and less than or equal to 2 mm. And the fifth distance and the sixth distance are not equal. By setting the range of the fifth distance as above, on the one hand, the transmission distance of carriers between the second solder strip 40 and the fourth solder strip 60 can be reduced. On the other hand, a smaller spacing can also be provided between the adjacent second solder strips 40 and the adjacent fourth solder strips 60, thereby shortening the overall carrier transmission distance of the cell and improving the power generation efficiency of the back-contact cell module.

[0079] As Figure 2 shown, the adjacent ones among the plurality of second solder strips 40 are spaced apart by a seventh preset distance L3, and the adjacent ones among the plurality of fourth solder strips 60 are spaced apart by an eighth preset distance L4. The absolute value of the difference between the seventh preset distance L3 and the eighth preset distance L4 is greater than or equal to 0 and less than or equal to 2.5 mm. In the embodiments of the present application, the seventh preset distance L3 and the eighth preset distance L4 are theoretically equal. However, due to process reasons, the absolute value of the difference between the seventh preset distance L3 and the eighth preset distance L4 is within the range of [0, 2.5], and the seventh preset distance L3 and the eighth preset distance L4 can also be regarded as equal. Through such a design, the uniform distribution of current in the cell can be improved, which helps to reduce the heat concentration phenomenon caused by uneven current distribution, thereby improving the overall efficiency and stability of the cell. During the production process, the production process can also be simplified and the production efficiency can be improved.

[0080] In the description of this specification, the descriptions with reference to the terms "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiments or examples. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0081] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A back-contact battery assembly, characterized in that, Comprising: A first battery string, the first battery string having a first edge and a second edge oppositely arranged in a first direction; A second battery string, the second battery string having a third edge and a fourth edge oppositely arranged in the first direction, the first battery string and the second battery string being spaced apart by a first preset distance D1 along the first direction, and the second edge and the third edge being close to each other; A plurality of first solder tapes, the plurality of first solder tapes being spaced apart along the first direction on the first battery string, the plurality of first solder tapes having the same polarity, and the plurality of first solder tapes being commonly connected to a first bus bar; A plurality of second solder tapes, the plurality of second solder tapes being spaced apart along the first direction on the second battery string, the plurality of second solder tapes having the same polarity, and the plurality of second solder tapes being commonly connected to a second bus bar; The distance between the solder tape closest to the second edge on the first battery string and the second edge in the first direction is a second preset distance D2, and the solder tape closest to the second edge on the first battery string is a first solder tape; The distance between the solder tape closest to the third edge on the second battery string and the third edge in the first direction is a third preset distance D3, and the solder tape closest to the third edge on the second battery string is a second solder tape; A junction box, the junction box having a first terminal and a second terminal, the first terminal and the second terminal being spaced apart by a fourth preset distance B, the first bus bar being connected to the first terminal, and the second bus bar being connected to the second terminal; wherein, The second preset distance D2 satisfies the following relationship: D2 = B + Δ1 + Δ2 - D1 - D3; the third preset distance D3 satisfies the following relationship: D3 = B + Δ1 + Δ2 - D1 - D2; wherein the range of the first preset value Δ1 is 3 - 15 mm, and the range of the second preset value Δ2 is 3 - 15 mm.

2. The back-contact battery assembly according to claim 1, characterized in that, The absolute value of the difference between the second preset distance D2 and the third preset distance D3 is greater than or equal to 0 and less than or equal to 2.5 mm.

3. The back-contact battery assembly according to claim 1, wherein The range of the second preset distance D2 is 5 - 15 mm, and the range of the third preset distance D3 is 5 - 15 mm.

4. The back-contact battery assembly according to claim 1, wherein The first battery string and the second battery string are of the same type of battery string.

5. The back-contact battery assembly according to claim 1, wherein, The junction box is arranged between the first battery string and the second battery string, the junction box having opposite first One end and a second end, the distance between the second edge of the first battery string and the first end in the first direction is a first distance, the distance between the third edge of the second battery string and the second end in the first direction is a second distance, the absolute value of the difference between the first distance and the second distance is greater than or equal to 0 and less than or equal to 3 mm, and the first preset value △1 and the second preset value △2 are equal.

6. The back contact battery assembly according to claim 1, characterized in that, The junction box is disposed between the first battery string and the second battery string. The junction box has opposite first and second ends in a first direction. The distance between the second edge of the first battery string and the first end in the first direction is a first distance, and the distance between the third edge of the second battery string and the second end in the first direction is a second distance. The first distance and the second distance are not equal, and the first preset value Δ1 and the second preset value Δ2 are not equal.

7. The back-contact battery assembly according to claim 1, wherein, It further includes a plurality of third solder tapes. The plurality of third solder tapes and the plurality of first solder tapes are alternately arranged at intervals along the first direction on the first battery string. The third solder tapes and the first solder tapes have opposite polarities.

8. The back-contact battery assembly according to claim 7, wherein, The plurality of third solder tapes and the plurality of first solder tapes are arranged alternately at equal intervals along the first direction on the first battery string.

9. The back-contact battery assembly according to claim 7, characterized in that, The distance between the nth first solder tape and the nth third solder tape on the first battery string is a third distance, and the distance between the nth third solder tape and the (n + 1)th first solder tape on the first battery string is a fourth distance. The third distance and the fourth distance are different, where n is a positive integer.

10. The back contact battery assembly according to claim 7, wherein, Adjacent ones of the plurality of first solder tapes are spaced apart by a fifth preset distance L1, and adjacent ones of the plurality of third solder tapes are spaced apart by a sixth preset distance L2. The absolute value of the difference between the fifth preset distance L1 and the sixth preset distance L2 is greater than or equal to 0 and less than or equal to 2.5 mm.

11. The back contact battery assembly according to claim 9, wherein, The range of the third distance is greater than 0 and less than or equal to 2 mm.

12. The back contact battery assembly according to claim 1, wherein, It further includes a plurality of fourth solder tapes. The plurality of second solder tapes and the plurality of fourth solder tapes are alternately arranged at intervals along the first direction on the second battery string. The second solder tapes and the fourth solder tapes have opposite polarities.

13. The back-contact battery assembly according to claim 12, wherein, The plurality of fourth solder tapes and the plurality of second solder tapes are arranged alternately at equal intervals along the first direction on the second battery string.

14. The back contact battery assembly according to claim 12, characterized in that, The distance between the nth second solder tape and the nth fourth solder tape on the second battery string is a fifth distance, and the distance between the nth fourth solder tape and the (n + 1)th second solder tape on the second battery string is a sixth distance. The fifth distance and the sixth distance are different, where n is a positive integer.

15. The back-contact battery assembly according to claim 14, wherein, The range of the fifth distance is greater than 0 and less than or equal to 2 mm.

16. The back contact battery assembly according to claim 12, characterized in that, Adjacent ones of the plurality of second solder tapes are spaced apart by a seventh preset distance L3, and adjacent ones of the plurality of fourth solder tapes are spaced apart by an eighth preset distance L4. The absolute value of the difference between the seventh preset distance L3 and the eighth preset distance L4 is greater than or equal to 0 and less than or equal to 2.5 mm.

17. A photovoltaic system, characterized in that, It includes the back-contact battery assembly according to any one of claims 1-16.

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