Back contact solar cell module and preparation method thereof

Abstract

The invention relates to the technical field of solar cells, in particular to a back contact solar cell module and a preparation method thereof. The back contact solar cell module comprises a cell piece, a bus bar, a plurality of first polarity welding strips, a plurality of second polarity welding strips and an insulating film, wherein the bus bar, the plurality of first polarity welding strips, the plurality of second polarity welding strips and the insulating film are all arranged on the back surface of the cell piece. The first polarity welding strip and the second polarity welding strip are arranged on the back face of the battery piece in a staggered mode, the first polarity welding strip is electrically connected with the bus bar, and the insulating film can isolate the bus bar from the battery piece. The first polarity welding strip and the second polarity welding strip are arranged on the two sides of the insulating film respectively in the thickness direction of the battery piece. The bus bars are arranged on the back surfaces of the battery pieces, so that the space between the battery pieces is saved, the area utilization rate of the back contact battery assembly is improved, the length of the welding strip is shortened, and the collection efficiency of current is improved.

Description

Technical Field

[0001] The present application relates to the technical field of solar cells, and in particular to a back-contact solar cell assembly and a preparation method thereof. Background Art

[0002] At present, the bus bars of conventional components are placed at the head, tail and middle of the components, which will occupy the component space, resulting in low component area utilization and power. Summary of the invention

[0003] The embodiments of the present application provide a back-contact solar cell module and a method for preparing the same, which aims to dispose a bus bar on the back side of the back-contact solar cell module, thereby improving the area utilization of the back-contact solar cell module and improving the current collection efficiency.

[0004] The embodiment of the present application provides a back-contact solar cell module, the back-contact solar cell module comprising:

[0005] Battery cells;

[0006] A bus bar, the bus bar is arranged on the back side of the battery cell;

[0007] A plurality of first polarity welding strips and a plurality of second polarity welding strips, wherein the first polarity welding strips and the second polarity welding strips are alternately arranged on the back side of the battery cell, and the first polarity welding strips are electrically connected to the bus bar;

[0008] An insulating film, wherein the insulating film can isolate the bus bar from the battery cell, and along the thickness direction of the battery cell, the first polarity welding strip and the second polarity welding strip are respectively arranged on both sides of the insulating film.

[0009] In a possible design, along the thickness direction of the battery cell, the first polarity welding strip is arranged above the bus bar, and the second polarity welding strip is arranged between the insulating film and the battery cell.

[0010] In a possible design, along the thickness direction of the battery cell, the first polarity welding strip is arranged between the bus bar and the insulating film, and the second polarity welding strip is arranged between the insulating film and the battery cell.

[0011] In a possible design, along the thickness direction of the battery cell, the insulating film is disposed between the bus bar and the battery cell.

[0012] In a possible design, the insulating film is provided with a second connection hole, and the bus bar can be electrically connected to the corresponding grid line on the battery cell through the second connection hole; or,

[0013] The insulating film is provided with a second connection hole, and the first polarity welding strip can be electrically connected to the corresponding gate line on the battery cell through the second connection hole.

[0014] In a possible design, the bus bar is disposed in the middle of the back side of the battery cell;

[0015] The width of the insulating film is greater than the width of the bus bar;

[0016] The busbar has a thickness of 0.1 mm to 0.2 mm.

[0017] In a possible design, a plurality of pads are provided on the back side of the battery cell;

[0018] Along the extending direction of the first polarity welding strip, the insulating film is located between two adjacent welding pads;

[0019] The distance between two adjacent pads is 8mm-20mm.

[0020] The present application also provides a method for preparing a back-contact solar cell module, which is used to prepare the above-mentioned back-contact solar cell module. The method comprises:

[0021] Laying a second polarity welding strip on the back of the battery cell, and welding the second polarity welding strip to the second polarity grid line on the battery cell;

[0022] Laying an insulating film on the back side of the battery cell;

[0023] A bus bar and a first polarity welding strip are laid on the back of the battery cell, and the first polarity welding strip is welded to the first polarity grid line on the battery cell.

[0024] In a possible design, before laying the bus bar and the first polarity welding strip on the back side of the battery cell, the preparation method further includes:

[0025] First, the first polarity welding strip is welded and fixed to the bus bar.

[0026] In a possible design, when laying the bus bar and the first polarity welding strip on the back side of the battery cell, the preparation method further includes:

[0027] Laying the first polarity welding tape on the top of the bus bar; or,

[0028] The first polarity welding tape is laid between the bus bar and the insulating film.

[0029] In the embodiment of the present application, by setting the bus bar on the back of the battery cell, the space between the battery cells is saved, and the space for placing the bus bar at the edge and the middle of the back contact solar cell module is reduced. When the size of the back contact solar cell module remains unchanged, more battery cells can be placed and larger battery cells can be used, which is beneficial to improve the area utilization of the back contact solar cell module, thereby improving the power of the back contact solar cell module.

[0030] At the same time, the bus bar is arranged on the back of the battery cell, which also shortens the connection length between the first polarity welding strip and the bus bar, and improves the current collection effect of the first polarity welding strip. The bus bar is arranged on the back of the battery cell, and the first polarity welding strip is connected to the bus bar, which can play the role of fixing the bus bar, and there is no need to fix the bus bar again.

[0031] In addition, by distributing the first polarity welding strip and the second polarity welding strip on both sides of the insulating film, the second polarity welding strip is arranged on the side of the insulating film away from the bus bar, so as to isolate the bus bar and the second polarity welding strip, and prevent the bus bar and the second polarity welding strip from contacting and short-circuiting. In addition, distributing the first polarity welding strip and the second polarity welding strip on both sides of the insulating film can also play a role in fixing the insulating film.

[0032] It should be understood that the foregoing general description and the following detailed description are exemplary only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A schematic top view of a back-contact solar cell provided in this application;

[0034] Figure 2 A cross-sectional view of a back-contact solar cell provided in the present application along a busbar cross section in one embodiment;

[0035] Figure 3 A cross-sectional view of a back-contact solar cell provided in the present application along a busbar cross section in another embodiment;

[0036] Figure 4 A schematic cross-sectional view of the insulating film provided in the present application;

[0037] Figure 5 A schematic diagram of a busbar wrapped with an insulating film provided in this application;

[0038] Figure 6 A schematic diagram of the insulating film provided in the present application wrapping the first polarity welding strip and the bus bar;

[0039] Figure 7 A cross-sectional view of a back-contact solar cell provided in the present application along a busbar cross section in another embodiment;

[0040] Figure 8 A cross-sectional view of a back-contact solar cell provided in the present application along a busbar cross section in one embodiment;

[0041] Fig. 9 A cross-sectional view of a non-back-contact solar cell provided in the present application along a busbar cross section in one embodiment;

[0042] Fig.10 A flow chart of the preparation of a back-contact solar cell provided in this application in one embodiment;

[0043] Fig.11 A flow chart of the preparation of a back-contact solar cell provided in the present application in another embodiment;

[0044] Fig.12 A flow chart of the preparation of a back-contact solar cell provided in the present application in another embodiment;

[0045] Fig.13 A preparation flow chart of a back-contact solar cell provided in the present application in another embodiment.

[0046] Reference numerals:

[0047] 1- Back contact solar cell module;

[0048] 11-battery cell;

[0049] 11a-back side;

[0050] 111- soldering pad;

[0051] 12-bus bar;

[0052] 13- first polarity welding strip;

[0053] 14- Second polarity welding strip;

[0054] 15- insulating film;

[0055] 151-first connecting hole;

[0056] 152-Second connecting hole.

[0057] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application. DETAILED DESCRIPTION

[0058] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0059] It should be clear that the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0060] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

[0061] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0062] It should be noted that the directional words such as "upper", "lower", "left", and "right" described in the embodiments of the present application are described at the angles shown in the accompanying drawings and should not be understood as limiting the embodiments of the present application. In addition, in the context, it is also necessary to understand that when it is mentioned that an element is connected to another element "upper" or "lower", it can not only be directly connected to another element "upper" or "lower", but also indirectly connected to another element "upper" or "lower" through an intermediate element.

[0063] In conventional solar cell modules, the busbars are located between adjacent cells. In this way, the busbars not only occupy a large area of ​​the module, but also the internal busbars can be seen through the front surface glass or transparent packaging material of the solar cell module. The directly exposed busbars not only expose the internal electrical structure design of the solar cell module. If the busbars are curled or offset during the lamination process, for double-glass modules, the potting glue and sealant will be irregularly shaped, and the appearance of the front junction box of the module will be ugly after curing, which will directly affect the appearance of the module.

[0064] To this end, this embodiment provides a back-contact solar cell module to solve the above technical problems.

[0065] like Figure 1 The schematic diagram of the back-contact solar cell module 1 shown in the figure includes a plurality of connected cell strings (not shown in the figure), the cell strings include a plurality of connected cell sheets 11, a bus bar 12 arranged on each cell sheet 11, a plurality of first polarity welding strips 13, a plurality of second polarity welding strips 14 and an insulating film 15.

[0066] This embodiment is described by taking a battery cell 11 and components connected to the battery cell 11 as an example. The battery cell 11 has a front side and a back side 11a that are arranged opposite to each other, and a bus bar 12, a plurality of first polarity welding strips 13, a plurality of second polarity welding strips 14 and an insulating film 15 are all arranged on the back side 11a of the battery cell 11.

[0067] Specifically, the back side 11a of the battery cell 11 is provided with a plurality of staggered first polarity grid lines (not shown in the figure) and second polarity grid lines (not shown in the figure), the first polarity welding strips 13 and the second polarity welding strips 14 are staggered on the back side 11a of the battery cell 11, and the first polarity welding strips 13 are correspondingly welded and connected to the first polarity grid lines to achieve electrical connection between the first polarity welding strips 13 and the first polarity grid lines, and the second polarity welding strips 14 are correspondingly welded and connected to the second polarity grid lines to achieve electrical connection between the second polarity welding strips 14 and the second polarity grid lines, thereby achieving the first polarity welding strips 13 and the second polarity welding strips 14 to play a role in guiding current.

[0068] The first polarity grid lines and the second polarity grid lines may be disposed on the back side 11 a of the battery cell 11 by screen printing.

[0069] Please continue to refer to Figure 1 The first polarity welding strips 13 are electrically connected to the bus bar 12, so that the bus bar 12 can collect the current on each first polarity welding strip 13, thereby realizing current concentration and transmission.

[0070] It should be noted that the polarity of the first polarity welding strip 13 is opposite to that of the second polarity welding strip 14, and the first polarity welding strip 13 can be a positive electrode welding strip or a negative electrode welding strip. For example, when the first polarity welding strip 13 is a positive electrode welding strip, the second polarity welding strip 14 is a negative electrode welding strip, the bus bar 12 is connected to the positive electrode welding strip, and the bus bar 12 collects the current on the positive electrode welding strip. When the first polarity welding strip 13 is a negative electrode welding strip, the second polarity welding strip 14 is a positive electrode welding strip, the bus bar 12 is connected to the negative electrode welding strip, and the bus bar 12 collects the current on the negative electrode welding strip.

[0071] like Figure 2 FIG. 1 is a cross-sectional view of a back contact solar cell module 1 in an embodiment. Figure 1 and Figure 2 The insulating film 15 can isolate the bus bar 12 from the battery cell 11, and the first polarity welding strip 13 and the second polarity welding strip 14 are respectively arranged on both sides of the insulating film 15 along the thickness direction Z of the battery cell 11. In other words, the insulating film 15 can isolate the bus bar 12 from contacting the battery cell 11, and the insulating film 15 can isolate the bus bar 12 from contacting the second polarity welding strip 14 to avoid short circuit.

[0072] In this embodiment, by arranging the busbar 12 on the back side 11a of the cell 11, the space between the cells 11 is saved, the size of the back contact solar cell module 1 is reduced, and the structure of the back contact solar cell module 1 is made more compact, which is conducive to improving the area utilization rate of the back contact solar cell module 1. At the same time, arranging the busbar 12 on the back side 11a of the cell 11 also shortens the connection length between the first polarity welding strip 13 and the busbar 12, and improves the current collection effect of the first polarity welding strip 13. Arranging the busbar 12 on the back side 11a of the cell 11 and connecting the busbar 12 with the first polarity welding strip 13 can play the role of fixing the busbar 12, and there is no need to fix the busbar 12 again.

[0073] In addition, in this embodiment, the first polarity welding strip 13 and the second polarity welding strip 14 are distributed on both sides of the insulating film 15, so that the second polarity welding strip 14 is set on the side of the insulating film 15 away from the bus bar 12, so as to isolate the bus bar 12 and the second polarity welding strip 14, and prevent the bus bar 12 and the second polarity welding strip 14 from contacting and causing a short circuit.

[0074] For more details, please refer to Figure 2 In one embodiment, the back contact solar cell module 1 includes a cell 11, an insulating film 15, a bus bar 12, a first polarity welding ribbon 13 and a second polarity welding ribbon 14. Along the thickness direction Z of the cell 11, the first polarity welding ribbon 13 is arranged above the bus bar 12, and the second polarity welding ribbon 14 is arranged between the insulating film 15 and the cell 11.

[0075] In this embodiment, the insulating film 15, the bus bar 12, the first polarity welding strip 13 and the second polarity welding strip 14 are all arranged on the back side 11a of the battery cell 11, the insulating film 15 is arranged between the bus bar 12 and the battery cell 11, the second polarity welding strip 14 is located between the insulating film 15 and the battery cell 11, the first polarity welding strip 13 is located above the bus bar 12, and the other parts of the first polarity welding strip 13 and the second polarity welding strip 14 are respectively welded to the corresponding pads 111.

[0076] In this embodiment, the first polarity welding strip 13 located above the bus bar 12 can fix the bus bar 12. At the same time, the first polarity welding strip 13 does not need to extend out of the battery cell 11 to connect with the bus bar 12, which is beneficial to improving the current collection efficiency and the stability of the back contact solar cell module 1.

[0077] like Figure 3The figure shows a cross-sectional schematic diagram of a back-contact solar cell in another embodiment. The back-contact solar cell assembly 1 includes a cell 11, an insulating film 15, a bus bar 12, a first polarity welding ribbon 13 and a second polarity welding ribbon 14. Along the thickness direction Z of the cell 11, the first polarity welding ribbon 13 is arranged between the bus bar 12 and the insulating film 15, and the second polarity welding ribbon 14 is arranged between the insulating film 15 and the cell 11.

[0078] In this embodiment, the insulating film 15, the bus bar 12, the first polarity welding strip 13 and the second polarity welding strip 14 are all arranged on the back side 11a of the battery cell 11, the insulating film 15 is arranged between the bus bar 12 and the battery cell 11, the second polarity welding strip 14 is located between the insulating film 15 and the battery cell 11, the first polarity welding strip 13 is located between the bus bar 12 and the insulating film 15, and the other parts of the first polarity welding strip 13 and the second polarity welding strip 14 are respectively welded to the corresponding pads 111.

[0079] In this embodiment, the first polarity welding strip 13 located below the bus bar 12 can fix the bus bar 12. At the same time, the first polarity welding strip 13 does not need to extend out of the battery cell 11 to connect with the bus bar 12, which is beneficial to improving the current collection efficiency and the stability of the back contact solar cell module 1.

[0080] like Figure 4 FIG. 1 is a schematic cross-sectional view of the insulating film 15, wherein the insulating film 15 is provided with a second connection hole 152. Figure 2 and Figure 4 The bus bar 12 can be electrically connected to the corresponding grid line on the battery cell 11 through the second connection hole 152 .

[0081] In this embodiment, by setting a second connection hole 152 that passes through the insulating film 15 along the thickness direction Z thereof, the upper end of the bus bar 12 is electrically connected to the first polarity welding strip 13, while the lower end of the bus bar 12 can be electrically connected to the first polarity grid line on the battery cell 11 through the second connection hole 152, so as to make full use of each grid line on the battery cell 11, better collect current, and improve the effect of collecting current.

[0082] Alternatively, please refer to Figure 3 and Figure 4 The insulating film 15 is provided with a second connection hole 152 , and the first polarity welding strip 13 can be electrically connected to the corresponding gate line on the battery cell 11 through the second connection hole 152 .

[0083] In this embodiment, by setting a second connection hole 152 that penetrates along the thickness direction Z on the insulating film 15, the first polarity welding strip 13 can be electrically connected to the first polarity grid line on the battery cell 11 through the second connection hole 152, so that the first polarity welding strip 13 is in full contact with the first polarity grid line. Even if the insulating film 15 is set, it can be ensured that the first polarity welding strip 13 is connected to enough first polarity grid lines, and each grid line on the battery cell 11 is fully utilized, effectively improving the efficiency of battery collection.

[0084] Please continue to refer to Figure 1 The bus bar 12 is disposed in the middle of the back side 11 a of the battery cell 11 , and the width of the insulating film 15 is greater than the width of the bus bar 12 to prevent the bus bar 12 from contacting the battery cell 11 and causing a short circuit in the battery cell 11 .

[0085] In addition, the back side 11a of the battery cell 11 is provided with a plurality of pads 111 for connecting the welding strips. Along the direction Y in which the first polarity welding strip 13 extends, the insulating film 15 is located between two adjacent pads 111 to prevent the insulating film 15 from shielding the pads 111 .

[0086] In some embodiments, the bus bar 12 has a thickness of 0.1 mm to 0.2 mm.

[0087] Illustratively, the bus bar 12 may have a thickness of 0.11 mm, 0.12 mm, 0.13 mm, 0.14 mm, 0.15 mm, 0.16 mm, 0.17 mm, 0.18 mm, 0.19 mm, 0.2 mm, or the like.

[0088] In this embodiment, the busbar 12 should be neither too thick nor too thin. If the busbar 12 is too thick (e.g., thicker than 0.2 mm), the height difference of the components will increase, and the stress generated during the component lamination process will be large, which may easily cause hidden cracks. If the busbar 12 is too thin (e.g., thinner than 0.1 mm), the current collection rate will be affected.

[0089] It should be noted that the thickness range of the busbar 12 can be further expanded or reduced according to actual needs, and can be specifically set according to actual conditions, which is not limited in this embodiment.

[0090] In some embodiments, the width of the bus bar 12 is 6 mm to 14 mm.

[0091] Illustratively, the width of the bus bar 12 may be 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, etc.

[0092] In this embodiment, the width of the bus bar 12 should be neither too wide nor too narrow. If the width of the bus bar 12 is too wide (e.g., wider than 14 mm), the bus bar 12 may extend out of the insulating film 15, and there is a risk that the bus bar 12 contacts the heterogeneous welding ribbon and causes a short circuit in the battery cell 11. If the width of the bus bar 12 is too narrow (e.g., narrower than 6 mm), the current collection rate is affected.

[0093] It should be noted that the width range of the busbar 12 can be further expanded or reduced according to actual needs, and can be specifically set according to actual conditions, which is not limited in this embodiment.

[0094] In some embodiments, the thickness of the insulating film 15 is 0.03 mm-0.3 mm.

[0095] Illustratively, the thickness of the insulating film 15 may be 0.03 mm, 0.06 mm, 0.09 mm, 0.12 mm, 0.15 mm, 0.18 mm, 0.21 mm, 0.24 mm, 0.27 mm, 0.3 mm, or the like.

[0096] In this embodiment, the thickness of the insulating film 15 should be neither too thick nor too thin. If the thickness of the insulating film 15 is too thick (e.g., thicker than 0.3 mm), the height difference of the components will increase, and the stress generated during the component lamination process will be large, which may easily cause hidden cracks. If the thickness of the insulating film 15 is too thin (e.g., thinner than 0.03 mm), it will be inconvenient to operate during pasting, and it will be easily deformed when pulled, and there will be a risk of damage to the long-term insulation.

[0097] It should be noted that the thickness range of the insulating film 15 can be further expanded or reduced according to actual needs, and can be specifically set according to actual conditions, which is not limited in this embodiment.

[0098] In some embodiments, the width of the insulating film 15 is 6 mm to 16 mm.

[0099] Illustratively, the width of the insulating film 15 may be 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, or the like.

[0100] In this embodiment, the width of the insulating film 15 should be neither too wide nor too narrow. If the width of the insulating film 15 is too wide (e.g., greater than 16 mm), the insulating film 15 will block the pad 111 disposed adjacent thereto, affecting the connection between the soldering ribbon and the soldering pad 111. If the width of the insulating film 15 is too narrow (e.g., less than 6 mm), the bus bar 12 will be exposed, and there is a risk of the bus bar 12 contacting with the heterosexual soldering ribbon and causing a short circuit.

[0101] It should be noted that the width range of the insulating film 15 can be further expanded or reduced according to actual needs, and can be specifically set according to actual conditions, which is not limited in this embodiment.

[0102] In some embodiments, the distance between two adjacent pads 111 is 8 mm-20 mm.

[0103] Exemplarily, the spacing between two adjacent pads 111 is 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm, etc.

[0104] In this embodiment, the spacing between two adjacent pads 111 should be neither too large nor too small. If the spacing is too large (e.g., greater than 20 mm), the adjacent fixing points on the welding strip are far away, resulting in the welding strip being unable to form a reliable connection with the corresponding gate line, affecting the current collection efficiency. If the adjacent spacing is too small (e.g., less than 8 mm), the insulating film 15 covers the adjacent pad 111, affecting the connection between the pad 111 and the welding strip.

[0105] It should be noted that the spacing between two adjacent pads 111 refers to the spacing between two adjacent pads 111 on the first polarity welding strip 13, or, refers to the spacing between two adjacent pads 111 on the second polarity welding strip 14, rather than the spacing between the pad 111 on the first polarity welding strip 13 and the pad 111 on the second polarity welding strip 14.

[0106] It should also be noted that the distance between two adjacent pads 111 can be further enlarged or reduced according to actual needs, and can be specifically set according to actual conditions, which is not limited in this embodiment.

[0107] Please refer to Figure 2 and Figure 3 In some embodiments, along the thickness direction Z of the battery cell 11 , the insulating film 15 may be disposed between the bus bar 12 and the battery cell 11 to isolate the bus bar 12 from the battery cell 11 .

[0108] Alternatively, in some embodiments, the insulating film 15 may wrap the bus bar 12 to isolate the bus bar 12 from the battery cell 11. Figure 5 , Figure 5 The figure shows a schematic diagram of an insulating film 15 wrapping a busbar 12, wherein the insulating film 15 is provided with a first connection hole 151, and the busbar 12 is electrically connected to the first polarity welding strip 13 through the first connection hole 151. In this embodiment, the first connection hole 151 is opened on the busbar 12, and the welding portion of the busbar 12 is exposed through the first connection hole 151, so that the busbar 12 is electrically connected to the first polarity welding strip 13.

[0109] The shape of the first connection hole 151 can be circular, elongated, etc. The first connection hole 151 only needs to ensure that the bus bar 12 and the first polarity welding strip 13 have sufficient contact area, and the specific shape can be set according to actual conditions, which is not limited in this embodiment.

[0110] Figure 6 The figure shows a schematic diagram of the insulating film 15 wrapping the bus bar 12 and the first polarity welding strip 13. The insulating film 15 can wrap the bus bar 12 and a part of the structure of the first polarity welding strip 13 together, and the other structure of the first polarity welding strip 13 extends outward from the insulating film 15 to be electrically connected to the first polarity grid line on the battery cell 11. In this embodiment, by wrapping a part of the structure of the first polarity welding strip 13 and the bus bar 12 together, there is no need to open a hole in the insulating film 15.

[0111] like Figure 7 The figure shows a schematic diagram of a back-contact solar cell module in another embodiment. The back-contact solar cell module 1 includes a cell 11, an insulating film 15, a bus bar 12, a first polarity welding strip 13 and a second polarity welding strip 14. Along the thickness direction Z of the cell 11, the first polarity welding strip 13 and the second polarity welding strip 14 are both arranged between the back side 11a of the cell 11 and the insulating film 15. The insulating film 15 wraps the bus bar 12. A first connection hole 151 is arranged on one side of the insulating film 15 close to the first polarity welding strip 13, and the bus bar 12 is electrically connected to the first polarity welding strip 13 through the first connection hole 151.

[0112] In this embodiment, by opening the first connection hole 151 on the insulating film 15 , the bus bar 12 is electrically connected to the first polarity welding strip 13 through the first connection hole 151 , so as to collect the current on the first polarity welding strip 13 .

[0113] Or, in some embodiments, Figure 7 In the illustrated embodiment, the insulating film 15 may also be disposed only below the bus bar 12 .

[0114] Figure 8 The figure shows a cross-sectional schematic diagram of a back-contact solar cell module 1. The back-contact solar cell solar module includes a cell 11, an insulating film 15, a bus bar 12, a first polarity welding strip 13 and a first polarity welding strip 14. Along the thickness direction Z of the cell 11, the insulating film 15 is distributed on both sides of the bus bar 12, the first polarity welding strip 13 is arranged between the insulating film 15 and the cell 11, and the second polarity welding strip 14 is arranged above the bus bar 12 and the two are isolated by the insulating film 15.

[0115] Along the thickness direction Z of the battery cell 11 , the insulating film 15 between the bus bar 12 and the first polarity welding ribbon 13 is provided with a first connection hole 151 , and the bus bar 12 and the first polarity welding ribbon 13 are electrically connected through the first connection hole 151 .

[0116] In this embodiment, a first connection hole 151 is opened on the insulating film 15 between the bus bar 12 and the first polarity welding strip 13, so that the bus bar 12 is electrically connected to the first polarity welding strip 13 through the first connection hole 151, thereby collecting the current on the first polarity welding strip 13. At the same time, the insulating film 15 is arranged above the bus bar 12, and the bus bar 12 is also isolated from the electrical connection with the second polarity welding strip 14 to prevent a short circuit.

[0117] Fig. 9 The figure shows a cross-sectional schematic diagram of a non-back-contact solar cell assembly 1. The non-back-contact solar cell comprises a cell 11, an insulating film 15, a bus bar 12 and a first polarity welding strip 13. The insulating film 15 isolates the bus bar 12 from the cell 11. The adjacently arranged first polarity welding strips 13 are staggered on both sides of the bus bar 12.

[0118] In this embodiment, the first polarity welding strips 13 arranged alternately up and down the bus bar 12 can play a role in fixing the bus bar 12 .

[0119] The welding strips of different polarities in the non-back contact solar cell module 1 are respectively arranged on the front and back sides 11a of the solar cell 11. That is, in some embodiments, Fig. 9 The first polarity welding in the embodiment shown can be arranged above the bus bar 12 or below the bus bar 12. The specific arrangement can be made according to the actual situation, and this embodiment is not limited here.

[0120] In some embodiments, Fig. 9 In the embodiment shown, the insulating film 15 may not be provided between the bus bar 12 and the battery cell 11. The specific setting may be made according to the actual situation, and this embodiment is not limited here.

[0121] Based on the above back-contact solar cell module 1, this embodiment further provides a method for preparing the back-contact solar cell module 1, which is used to prepare the above back-contact solar cell module 1.

[0122] like Fig.10 The figure shows a preparation flow chart of a back contact solar cell module 1 in one embodiment, wherein the preparation method comprises:

[0123] S11: laying a second polarity welding ribbon 14 on the back side 11a of the battery cell 11, and welding the second polarity welding ribbon 14 to the second polarity grid line on the battery cell 11;

[0124] S12: Laying an insulating film 15 on the back side 11a of the battery cell 11;

[0125] S13: Laying the bus bar 12 on the back side 11a of the battery cell 11;

[0126] S14 : Laying the first polarity welding ribbon 13 on the back side 11 a of the battery cell 11 , and welding the first polarity welding ribbon 13 to the first polarity grid line on the battery cell 11 .

[0127] The specific content and technical effects of the preparation method in this embodiment can be referred to above, and this embodiment will not be described in detail here.

[0128] like Fig.11 The figure shows a preparation flow chart of a back contact solar cell module 1 in another embodiment, wherein the preparation method comprises:

[0129] S21: laying a second polarity welding ribbon 14 on the back side 11a of the battery cell 11, and welding the second polarity welding ribbon 14 to the second polarity grid line on the battery cell 11;

[0130] S22: Laying an insulating film 15 on the back side 11a of the battery cell 11;

[0131] S23: Laying a first polarity welding ribbon 13 on the back side 11a of the battery cell 11, and welding the first polarity welding ribbon 13 to the first polarity grid line on the battery cell 11;

[0132] S24 : Laying the bus bar 12 on the back surface 11 a of the battery cell 11 .

[0133] The specific content and technical effects of the preparation method in this embodiment can be referred to above, and this embodiment will not be described in detail here.

[0134] like Fig.12 The figure shows a preparation flow chart of a back contact solar cell module 1 in another embodiment, wherein the preparation method comprises:

[0135] S31: laying a second polarity welding ribbon 14 on the back side 11a of the battery cell 11, and welding the second polarity welding ribbon 14 to the second polarity grid line on the battery cell 11;

[0136] S32: Laying an insulating film 15 on the back side 11a of the battery cell 11;

[0137] S33: Fix the first polarity welding strip 13 on the top of the bus bar 12;

[0138] S34 : Laying the first polarity welding ribbon 13 and the bus bar 12 together on the back side 11 a of the battery cell 11 , and welding the first polarity welding ribbon 13 to the first polarity grid line on the battery cell 11 .

[0139] The specific content and technical effects of the preparation method in this embodiment can be referred to above, and this embodiment will not be described in detail here.

[0140] like Fig.13 The figure shows a preparation flow chart of a back contact solar cell module 1 in another embodiment, wherein the preparation method comprises:

[0141] S41: laying a second polarity welding ribbon 14 on the back side 11a of the battery cell 11, and welding the second polarity welding ribbon 14 to the second polarity grid line on the battery cell 11;

[0142] S42: Laying an insulating film 15 on the back side 11a of the battery cell 11;

[0143] S43: Fix the first polarity welding strip 13 below the bus bar 12;

[0144] S44 : Laying the first polarity welding ribbon 13 and the bus bar 12 together on the back side 11 a of the battery cell 11 , and welding the first polarity welding ribbon 13 to the first polarity grid line on the battery cell 11 .

[0145] In some embodiments, a back-contact solar cell assembly includes a first cover plate, a first adhesive film, a cell string, a second adhesive film, and a second cover plate that are stacked, and the cell string includes a plurality of electrically connected cell sheets.

[0146] The first cover is located on the light-facing side of the battery string, used to transmit sunlight, and also used to improve the waterproof and moisture-proof ability of the back-contact solar cell module, and seal the battery string together with the second cover. During the lamination process of the back-contact solar cell module, the first adhesive film and the second adhesive film are used to encapsulate the battery string to prevent the external environment from affecting the performance of the battery string, and at the same time, the first cover, the battery string and the second cover are bonded into a whole.

[0147] The material of the first cover plate can be coated glass or a fluorocarbon resin / PET composite transparent plate, and the material of the second cover plate can include glass, fluoropolymer, polyamide (PA), polyethylene (PE), polyethylene terephthalate (PET), fluorocarbon resin (PEVE), polyvinylidene fluoride (PVDF) or polyvinyl fluoride (PVF), etc.

[0148] The material of the first adhesive film and the second adhesive film can be one of the materials such as ethylene-vinyl acetate copolymer (Ethylene-VinylAcetate Copolymer EVA), polyolefin elastomer (Polyolefin Elastomer POE), polyvinyl butyral (Polyvinyl Butyral PVB), and can also be EPE adhesive film (EVA-POE-EVA co-extrusion structure) or EP adhesive film (EVA-POE co-extrusion structure).

[0149] The specific content and technical effects of the preparation method in this embodiment can be referred to above, and this embodiment will not be described in detail here.

[0150] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. 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 solar cell module, characterized in that: The back contact solar cell module (1) comprises: Battery cell (11); A bus bar (12), the bus bar (12) being arranged on the back side (11a) of the battery cell (11); A plurality of first polarity welding strips (13) and a plurality of second polarity welding strips (14), wherein the first polarity welding strips (13) and the second polarity welding strips (14) are alternately arranged on the back side (11a) of the battery cell (11), and the first polarity welding strips (13) are electrically connected to the bus bar (12); An insulating film (15), wherein the insulating film (15) is capable of isolating the bus bar (12) and the battery cell (11), and along the thickness direction (Z) of the battery cell (11), the first polarity welding strip (13) and the second polarity welding strip (14) are respectively arranged on both sides of the insulating film (15).

2. The back contact solar cell module according to claim 1, characterized in that: Along the thickness direction (Z) of the battery cell (11), the first polarity welding strip (13) is arranged above the bus bar (12), and the second polarity welding strip (14) is arranged between the insulating film (15) and the battery cell (11).

3. The back contact solar cell module according to claim 1, characterized in that: Along the thickness direction (Z) of the battery cell (11), the first polarity welding strip (13) is arranged between the bus bar (12) and the insulating film (15), and the second polarity welding strip (14) is arranged between the insulating film (15) and the battery cell (11).

4. The back contact solar cell module according to any one of claims 1 to 3, characterized in that: Along the thickness direction (Z) of the battery cell (11), the insulating film (15) is arranged between the bus bar (12) and the battery cell (11).

5. The back contact solar cell module according to claim 1, characterized in that: The insulating film (15) is provided with a second connection hole (152), and the bus bar (12) can be electrically connected to a corresponding grid line on the battery cell (11) through the second connection hole (152); or, The insulating film (15) is provided with a second connection hole (152), and the first polarity welding strip (13) can be electrically connected to a corresponding gate line on the battery cell (11) through the second connection hole (152).

6. The back contact solar cell module according to any one of claims 1 to 3, characterized in that: The bus bar (12) is arranged at a middle position of the back side (11a) of the battery cell (11); The width of the insulating film (15) is greater than the width of the bus bar (12); The busbar has a thickness of 0.1 mm to 0.2 mm.

7. The back contact solar cell module according to claim 6, characterized in that: The back side (11a) of the battery cell (11) is provided with a plurality of welding pads (111); Along the direction (Y) in which the first polarity welding strip (13) extends, the insulating film (15) is located between two adjacent welding pads (111); The distance between two adjacent pads is 8mm-20mm.

8. A method for preparing a back-contact solar cell module, for preparing the back-contact solar cell module (1) according to any one of claims 1 to 7, characterized in that: The preparation method comprises: Laying a second polarity welding strip (14) on the back side (11a) of the battery cell (11), and welding the second polarity welding strip (14) to the second polarity grid line on the battery cell (11); Laying an insulating film (15) on the back side (11a) of the battery cell (11); A bus bar (12) and a first polarity welding strip (13) are laid on the back side (11a) of the battery cell (11), and the first polarity welding strip (13) is welded to the first polarity grid line on the battery cell (11).

9. The method for preparing a back contact solar cell module according to claim 8, characterized in that: Before laying the bus bar (12) and the first polarity welding strip (13) on the back side (11a) of the battery cell (11), the preparation method further comprises: First, the first polarity welding strip (13) and the bus bar (12) are welded and fixed.

10. The method for preparing a back contact solar cell module according to claim 9, characterized in that: When laying the bus bar (12) and the first polarity welding strip (13) on the back side (11a) of the battery cell (11), the preparation method further comprises: Laying the first polarity welding strip (13) above the bus bar (12); or, The first polarity welding strip (13) is laid between the bus bar (12) and the insulating film (15).

Images