Photovoltaic module

Abstract

The application discloses a photovoltaic module, which comprises a cell, an insulating structure and a busbar arranged in sequence along the thickness direction of the photovoltaic module. A first solder strip is connected to the back surface of the cell, a second solder strip is connected to the front surface of the cell, and the second solder strip is connected to the second surface of the busbar through a bending extension. The insulating structure comprises a first adhesive layer, an insulating layer and a second adhesive layer arranged in sequence along the thickness direction of the cell. The first adhesive layer is adjacent to the back surface of the cell, and the second adhesive layer is adjacent to the first surface of the busbar. In the photovoltaic module, the first adhesive layer is arranged to bond the cell and the insulating structure, and to provide a buffer for the cell; the insulating layer is arranged to insulate the cell and the busbar; and the second adhesive layer is arranged to bond the busbar and the insulating structure, so as to prevent the busbar from slipping and to provide a buffer for the cell. In this way, the contact short circuit between the busbar and the cell is prevented, and the busbar and the insulating structure are prevented from damaging the cell.

Description

Technical Field

[0001] This application relates to the field of solar cell technology, and more particularly to a photovoltaic module. Background Technology

[0002] In the photovoltaic industry, with technological advancements, products such as back-contact modules, tandem-busbar modules, and multi-cell modules have emerged. Further technological development in the photovoltaic industry has led to the development of busbar-flipped modules to improve module power output. This involves flipping the busbars, which are originally on the same horizontal plane as the solar cells, to the back of the cells. This avoids the busbars occupying additional cell area within the photovoltaic module, thereby increasing the effective cell area and improving module efficiency.

[0003] However, folding the busbar on the back of the solar cell may cause short circuits and microcracks, affecting the yield and productivity of photovoltaic modules. Utility Model Content

[0004] This application discloses a photovoltaic module for improving the yield and productivity of photovoltaic modules.

[0005] To achieve the above objectives, in a first aspect, this application discloses a photovoltaic module, comprising: A solar cell, the solar cell including a front side and a back side along its thickness direction; A busbar, the busbar including a first surface and a second surface along the thickness direction of the battery cell, the busbar being disposed on the back side, and the first surface being close to the back side; An insulating structure is located between the back surface and the first surface. The insulating structure includes a first adhesive layer, an insulating layer, and a second adhesive layer sequentially disposed along the direction from the back surface to the first surface. The first adhesive layer is disposed on the back surface, and the second adhesive layer is connected to the first surface. A first solder strip is disposed on the back side, and a first adhesive layer is disposed on at least a portion of the first solder strip corresponding to the busbar. The second solder strip is disposed on the front side and extends at least partially beyond the edge of the cell to form an extension, which is bent along the thickness direction of the cell to the back side to connect to the second surface.

[0006] As an optional implementation, the first adhesive layer is an ethylene-vinyl acetate copolymer; and / or, The insulating layer is made of polyethylene terephthalate or polyolefin; and / or... The second adhesive layer is an ethylene-vinyl acetate copolymer.

[0007] In one optional implementation, the thickness of the second adhesive layer is h1, the thickness of the insulating layer is h2, and the thickness of the first adhesive layer is h3; Satisfying: h3 > h1; and / or, The h1 is 0.01mm-0.15mm; and / or, The h2 is 0.01mm-0.15mm; and / or, The h3 is 0.05mm-0.50mm.

[0008] As an optional implementation, both the first solder strip and the second solder strip extend along a first direction, which is the width direction of the battery cell; Along the first direction, the width of the busbar is W1, and the width of the insulation structure is W2; The W1 is 2mm-15mm, and the W2 is 10mm-80mm; and / or, W2 ≥ W1.

[0009] As an alternative implementation, the photovoltaic module further includes a positioning tape that adheres to the second side and the back side.

[0010] As an optional implementation, both the first solder strip and the second solder strip extend along a first direction, which is the width direction of the battery cell; Along the first direction, the width of the busbar is W1, and the length of the positioning tape is L1, satisfying: L1 > W1.

[0011] As an optional implementation, both the first solder strip and the second solder strip extend along a first direction, which is the width direction of the battery cell; Along the first direction, the busbar has a first interval to the edge of the battery cell, and the insulating structure extends at least partially into the first interval; The positioning tape includes a first adhesive segment, a second adhesive segment, and a third adhesive segment connected sequentially along the first direction. The first adhesive segment extends into the first interval to adhere to the insulating structure, the second adhesive segment adheres to the second surface, and the third adhesive segment adheres to the back surface.

[0012] As an alternative implementation, along the first direction, the end of the first adhesive segment is close to the edge of the battery cell to be bonded to an insulating structure located at the first interval, the width of the insulating structure being W2 and the length of the positioning tape being L1, satisfying: L1 > W2.

[0013] As an optional implementation, both the first solder strip and the second solder strip extend along a first direction, which is the width direction of the battery cell; The first welding strip consists of multiple strips, which are spaced apart along the second direction on the back side. The positioning tape is attached to the back side and located between two first welding strips. Along the second direction, the spacing between two adjacent first solder strips is d, and the width of the positioning tape is W3, satisfying: d > W3; Wherein, the second direction is the length direction of the battery cell.

[0014] As an optional implementation, the photovoltaic module further includes a backsheet and a spacer strip, wherein the spacer strip and the backsheet are stacked sequentially on the second surface, and along the first direction, the spacer strip covers the busbar and the insulation structure; Wherein, the first direction is the width direction of the battery cell.

[0015] As an optional implementation, the extension segment includes a first sub-segment, a bent segment, and a second sub-segment connected in sequence, wherein the first sub-segment is located on the front side of the battery cell, and the second sub-segment is connected to the second side; Along the thickness direction of the battery cell, the second sub-segment is at least partially offset from the first sub-segment, and part of the padding strip is stacked on the second sub-segment.

[0016] As an alternative implementation, along the first direction, the first segment is inclined relative to the second solder strip, the second segment is inclined relative to the first solder strip, and the inclination directions of the first segment and the second segment intersect.

[0017] As an optional implementation, the extension segment includes a first sub-segment, a bent segment, and a second sub-segment connected in sequence. The first sub-segment is connected to the second welding strip, and the second sub-segment is connected to the second surface. The bent segment is constructed as an arc segment with an arc vertex. The distance between the arc vertex and the edge of the battery cell is L2, where L2 is 1mm-3mm.

[0018] As an alternative implementation, a buffer space is formed between the first sub-segment, the bent segment, and the second sub-segment, and the insulating structure extends at least partially into the buffer space.

[0019] Secondly, this application also discloses a photovoltaic module, comprising: A solar cell, the solar cell including a front side and a back side along its thickness direction; A busbar, the busbar including a first surface and a second surface along the thickness direction of the battery cell, the busbar being disposed on the back side, and the first surface being close to the back side; An insulating structure is located between the back surface and the first surface. The insulating structure includes a first adhesive layer and an insulating layer sequentially disposed along the direction from the back surface to the first surface. The first adhesive layer is disposed on the back surface, and the insulating layer is connected to the first surface. A first solder strip is disposed on the back side, and a first adhesive layer is disposed on at least a portion of the first solder strip corresponding to the busbar. The second solder strip is disposed on the front side and extends at least partially beyond the edge of the cell to form an extension, which is bent along the thickness direction of the cell to the back side to connect to the second surface.

[0020] Compared with the prior art, the beneficial effects of this application are as follows: This application discloses a photovoltaic module in which a busbar is bent and folded onto the back of the solar cell via an extension section. To prevent a short circuit caused by the connection between the busbar and the first solder strip on the back of the solar cell, an insulating structure is provided between the busbar and the solar cell. This insulating structure consists of a second adhesive layer, an insulating layer, and a first adhesive layer, with the insulating layer playing a primary insulating role. Since the busbar is mounted on the insulating structure, a second adhesive layer is provided to secure it to the insulating structure and prevent it from slipping off during subsequent encapsulation. The first adhesive layer is provided between the insulating structure and the solar cell primarily because both the busbar and the insulating structure are located on the back of the solar cell. When the back of the solar cell is placed, the protruding busbar and insulating structure might press against the back of the solar cell, potentially damaging it. Therefore, a first adhesive layer is provided between the insulating layer and the back of the solar cell. This soft and adhesive first adhesive layer not only bonds the insulating structure to the solar cell but also protects the solar cell. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the first structure of the photovoltaic module disclosed in the embodiments of this application; Figure 2 This is a side view of a photovoltaic module disclosed in an embodiment of this application; Figure 3This is a schematic diagram of a second structure of a photovoltaic module disclosed in an embodiment of this application; Figure 4 This is a schematic diagram of a third structure of a photovoltaic module disclosed in an embodiment of this application; Figure 5 This is a schematic diagram of the fourth structure of the photovoltaic module disclosed in the embodiments of this application; Figure 6 This is a top view of the photovoltaic module disclosed in the embodiments of this application; Figure 7 This is a schematic diagram of the fifth structure of the photovoltaic module disclosed in the embodiments of this application; Figure 8 This is a schematic diagram of the sixth structure of the photovoltaic module disclosed in the embodiments of this application; Figure 9 This is another side view of the photovoltaic module disclosed in the embodiments of this application; Figure 10 This is a schematic diagram of the seventh structure of the photovoltaic module disclosed in the embodiments of this application; Figure 11 for Figure 6 A magnified view of a section at point A in the middle; Figure 12 This is another side view of the photovoltaic module disclosed in the embodiments of this application.

[0023] Explanation of reference numerals in the attached figures: 100. Photovoltaic module; 1. Solar cell; 1a. Front side; 1b. Back side; 1c. First gap; 11. Edge of solar cell; 2. Busbar; 2a. First side; 2b. Second side; 3. Insulation structure; 31. First adhesive layer; 32. Insulation layer; 33. Second adhesive layer; 4. First solder strip; 5. Second solder strip; 51. Extension section; 511. First sub-segment; 512. Bending section; 513. Second sub-segment; 51a. Buffer space; 6. Positioning tape; 61. First adhesive section; 62. Second adhesive section; 63. Third adhesive section; 7. Backsheet; 8. Spacer strip. Detailed Implementation

[0024] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0025] In this application, the terms "front" and "back," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated devices, elements, or components to having a specific orientation, or to be constructed and operated in a specific orientation.

[0026] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0027] Furthermore, the terms "installation," "setup," "equipped with," "connection," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0028] Furthermore, the terms "first," "second," etc., are primarily used to distinguish different devices, components, or parts (which may be the same or different in specific type and construction), and are not intended to indicate or imply the relative importance or quantity of the indicated devices, components, or parts. Unless otherwise stated, "a plurality of" means two or more.

[0029] In the photovoltaic industry, with technological advancements, products such as back-contact modules, tandem grid modules, and multi-cell modules have emerged. Further technological development in the photovoltaic industry has led to the development of busbar-flipped modules to improve module power output. This involves flipping the busbars, which are originally on the same horizontal plane as the solar cells, to the back of the cells. This avoids the busbars occupying additional cell area within the photovoltaic module, thereby increasing the effective area of ​​the cells and improving module efficiency.

[0030] However, folding the busbar causes the solder ribbons and the busbar itself to stack heavily on the solar cell. This stacking area can exert significant pressure on the cell, potentially leading to microcracks on the back side and affecting the yield and overall quality of the photovoltaic module. Furthermore, during the folding process, the solder ribbons on the busbar may come into contact with the solder ribbons on the back of the solar cell, causing a short circuit and impacting the cell's efficiency.

[0031] To address this issue, this application discloses a photovoltaic module in which an insulating structure is provided between the busbar and the back of the solar cell after the busbar is folded over. This insulating structure insulates the busbar from the back of the solar cell, preventing short circuits caused by contact between the solder ribbons. The insulating structure also adheres the busbar to the back of the solar cell, preventing it from slipping off. Furthermore, the insulating structure uses an adhesive layer, typically a flexible and adhesive material, which buffers the stacked area of ​​the busbar and solar cell, reducing the pressure exerted on the solar cell by the busbar and solder ribbons and preventing microcracks in the solar cell.

[0032] The technical solution of this application will be further described below with reference to the embodiments and accompanying drawings.

[0033] Please see Figure 1 and Figure 2 This application discloses a photovoltaic module 100, including a solar cell 1 and a busbar 2. The solar cell 1 includes a front side 1a and a back side 1b along its thickness direction Z. Typically, the front side 1a of the solar cell 1 is the light-receiving surface, and the back side 1b is the back-lighting surface. The busbar 2 includes a first surface 2a and a second surface 2b along the thickness direction Z of the solar cell 1. When the busbar 2 is disposed on the back side 1b of the solar cell 1, the first surface 2a is closer to the back side 1b of the solar cell 1. The photovoltaic module 100 also includes an insulating structure 3, a first solder ribbon 4, and a second solder ribbon 5. The insulating structure 3 is located between the back side 1b and the first surface 2a of the solar cell 1. The insulating structure 3 includes a first adhesive layer 31, an insulating layer 32, and a second adhesive layer 33 sequentially disposed along the direction from the back side 1b to the first surface 2a. The first adhesive layer 31 is disposed on the back side 1b, and the second adhesive layer 33 is connected to the first surface 2a. The first solder strip 4 is disposed on the back side 1b, the first adhesive layer 31 is disposed on at least a portion of the first solder strip 4 corresponding to the busbar 2, the second solder strip 5 is disposed on the front side 1a, the second solder strip 5 extends at least a portion of the edge 11 of the battery cell to form an extension 51, the extension 51 is bent along the thickness direction Z of the battery cell 1 to the back side 1b to connect to the second side 2b.

[0034] It is understandable that the first adhesive layer 31 and the second adhesive layer 33 can be adhesive or glue with adhesiveness and flexibility. They can not only bond the busbar 2 to the back side 1b of the battery cell 1, but also have a certain buffering effect on the busbar 2 and solder ribbon stacked on the back side 1b of the battery cell 1, so as to avoid the stacked solder ribbon and busbar 2 causing microcracks to the battery cell 1.

[0035] In the photovoltaic module 100 disclosed in this application, after the busbar 2 is folded onto the back side 1b of the solar cell 1, an insulating structure 3 is provided between the busbar 2 and the solar cell 1. An insulating layer 32 insulates the busbar 2 and the first solder strip 4 on the back side 1b of the solar cell 1, preventing direct contact and short circuits. A first adhesive layer 31 is bonded to the back side 1b, allowing the insulating structure 3 to be fixed relative to the solar cell 1. Furthermore, because the first adhesive layer 31 is flexible, it can buffer the pressure of the insulating structure 3 and the busbar 2 stacked on the solar cell 1, preventing microcracks in the solar cell 1. Additionally, considering that if the busbar 2 slips off the insulating structure 3 when it is mounted on the insulating structure 3, it could potentially cause a short circuit between the busbar 2 and the solar cell 1. In this regard, the present application also uses a second adhesive layer 33 to bond the busbar 2 to the insulating structure 3, thereby fixing the busbar 2 to the insulating structure 3, which can prevent the busbar 2 from slipping off the battery cell 1 after it is folded to the back side 1b of the battery cell 1.

[0036] It is understandable that busbar 2 was on the same plane as battery cell 1 before it was folded over, such as... Figure 3 As shown in the example, before folding the busbar 2, an insulating structure 3 is first set on the back side 1b of the battery cell 1, and then the busbar 2 is folded onto the insulating structure 3, as shown. Figure 4 as well as Figure 5 The example provided.

[0037] Understandably, the solar cell 1 includes a silicon substrate and a doped layer, with the doped layer disposed on the surface of the silicon substrate. The silicon substrate can be an N-type silicon substrate or a P-type silicon substrate. The doped layer can be a diffusion layer, such as a boron-doped layer or a phosphorus-doped layer, or a polycrystalline silicon layer, such as a P-type doped polycrystalline silicon layer or an N-type doped polycrystalline silicon layer, or an amorphous silicon layer, such as a P-type doped amorphous silicon layer or an N-type doped amorphous silicon layer.

[0038] For example, the cell type of the solar cell 1 may be a passivated contact solar cell (TOPCon solar cell), a back contact solar cell (BC solar cell), a heterojunction solar cell (HJT solar cell), or an emitter and back passivated solar cell (PERC solar cell).

[0039] Typically, the solar cell 1 is a square sheet. Therefore, in solar cell 1, the first direction X can be the length direction of solar cell 1, and the second direction Y can be the width direction of solar cell 1. Alternatively, the first direction X can also be the width direction of solar cell 1, and the second direction Y can also be the length direction of solar cell 1. Figure 1 In the example, X indicates the first direction X, and Y indicates the second direction Y. Figure 1 In the example, Z indicates the thickness direction Z of the battery cell 1.

[0040] It is understood that the square sheet can be a square sheet with the same length and width, or a rectangular sheet with different length and width. This application does not make any specific limitation here.

[0041] like Figure 1 As shown, the battery cell 1 can be a square sheet with two ends along the length direction and two sides along the width direction. The first solder strip 4 and the second solder strip 5 can extend along the two ends along the length direction of the battery cell 1, or the first solder strip 4 and the second solder strip 5 can extend along the two ends along the width direction of the battery cell 1.

[0042] In some embodiments, the first adhesive layer 31 may be an ethylene-vinyl acetate copolymer, i.e., EVA (ethylene-vinyl acetate copolymer) material.

[0043] Understandably, EVA material has good thermoplasticity, which facilitates the connection of the first adhesive layer 31 to the battery cell 1 and the insulating layer 32 after heating. Moreover, EVA material has low flowability, which gives it a good cushioning effect. When EVA material, as the first adhesive layer 31, comes into contact with the battery cell 1, it can buffer the pressure on the battery cell 1 caused by the busbar 2 bending to the back side 1b of the battery cell 1, thus preventing microcracks from occurring in the battery cell 1.

[0044] In some embodiments, the insulating layer 32 may be a polyethylene terephthalate material or a polyolefin material.

[0045] The insulating layer 32 is made of polyethylene terephthalate or polyolefin materials, which have good insulation and stability, providing stable insulation for the solar cells 1 and busbars 2. Polyethylene terephthalate, in particular, has good heat resistance, preventing the insulating layer 32 from failing under high-temperature conditions when the photovoltaic module 100 is exposed to sunlight for extended periods.

[0046] In some embodiments, the second adhesive layer 33 may be an ethylene-vinyl acetate copolymer, i.e., EVA (ethylene-vinyl acetate copolymer) material.

[0047] Understandably, EVA material has good thermoplasticity, which facilitates the connection of the busbar 2 and the insulating layer 32 after heating. Moreover, EVA material has low fluidity, which gives it a good cushioning effect, thus absorbing the pressure on the battery cell 1 after the busbar 2 bends to the back side 1b of the battery cell 1, and preventing microcracks from occurring in the battery cell 1.

[0048] Please see Figure 2 In some embodiments, the thickness of the second adhesive layer 33 is h1, and the thickness of the insulating layer 32 is h2, satisfying that h2 > h1.

[0049] The second adhesive layer 33 connects the insulating layer 32 and the busbar 2. Its main function is to bond the busbar 2 and the insulating layer 32, preventing the busbar 2 from slipping. Since the photovoltaic module 100 is relatively thin overall, to avoid increasing the overall thickness of the photovoltaic module 100 due to the added insulating structure 3, the thickness of each layer of the insulating structure 3 needs to be controlled separately. The insulating layer 32 provides insulation and requires a certain thickness to ensure its insulating effect, while the second adhesive layer 33 mainly provides adhesion and can be made relatively thin. Therefore, by controlling h2 > h1, the overall thickness of the photovoltaic module 100 is kept relatively thin while ensuring the functions of the second adhesive layer 33 and the insulating layer 32.

[0050] In some embodiments, the thickness of the first adhesive layer 31 is h3, satisfying that h3 > h1.

[0051] Compared to the second adhesive layer 33, which is mainly used for bonding, the first adhesive layer 31 can not only bond the insulating layer 32 to the battery cell 1, but also buffer the pressure of the busbar 2 and the insulating structure 3 on the battery cell 1. Therefore, the first adhesive layer 31 is made thicker than the second adhesive layer 33 to improve its buffering effect.

[0052] Optionally, h1 can be 0.01mm-0.15mm.

[0053] For example, h1 can be 0.01mm-0.05mm, 0.05mm-0.10mm, 0.10mm-0.15mm, etc. For instance, h1 can be 0.01mm, 0.03mm, 0.05mm, 0.07mm, 0.10mm, 0.13mm, or 0.15mm, etc.

[0054] This application controls the thickness of the second adhesive layer 33 to within 0.01mm-0.15mm. On the one hand, this avoids the second adhesive layer 33 being too thin, which would affect its bonding effect and stability, as it is prone to breakage. On the other hand, it avoids the second adhesive layer 33 being too thick, which would affect the overall thickness of the photovoltaic module 100. If the second adhesive layer 33 is too thick, the insulation structure 3 may become thicker, resulting in thicker areas where the busbar 2 and insulation structure 3 are stacked on the photovoltaic module 100, causing greater surface undulations. Therefore, controlling the thickness of the second adhesive layer 33 to within 0.01mm-0.15mm ensures the bonding effect of the second adhesive layer 33 while preventing the photovoltaic module 100 from becoming too thick.

[0055] Optionally, h2 can be 0.01mm-0.15mm.

[0056] For example, h2 can be 0.01mm-0.05mm, 0.05mm-0.10mm, 0.10mm-0.15mm, etc. For instance, h2 can be 0.01mm, 0.03mm, 0.05mm, 0.07mm, 0.10mm, 0.13mm, or 0.15mm, etc.

[0057] This application controls the thickness of the insulating layer 32 to within 0.01mm-0.15mm. On the one hand, this avoids the insulating layer 32 being too thin, which could affect its insulation performance and stability. If the insulating layer 32 is too thin, it may be damaged, affecting its insulation performance. On the other hand, it avoids the insulating layer 32 being too thick, which could affect the overall thickness of the photovoltaic module 100. If the insulating layer 32 is too thick, the insulating structure 3 may become thicker, resulting in thicker areas where the busbar 2 and the insulating structure 3 are stacked in the photovoltaic module 100, causing greater surface undulations in the photovoltaic module 100. Therefore, controlling the thickness of the insulating layer 32 to within 0.01mm-0.15mm ensures the insulation effect of the insulating layer 32 while preventing the photovoltaic module 100 from becoming too thick.

[0058] Optionally, h3 can be 0.05mm-0.50mm.

[0059] For example, h3 can be 0.05mm-0.10mm, 0.10mm-0.15mm, 0.15mm-0.20mm, 0.20mm-0.25mm, 0.25mm-0.30mm, 0.30mm-0.35mm, 0.35mm-0.40mm, 0.40mm-0.45mm, 0.45mm-0.50mm, etc. For example, h3 can be 0.05mm, 0.07mm, 0.10mm, 0.13mm, 0.15mm, 0.17mm, 0.20mm, 0.23mm, 0.25mm, 0.27mm, 0.30mm, 0.33mm, 0.35mm, 0.37mm, 0.40mm, 0.43mm, 0.45mm, 0.47mm, or 0.50mm, etc.

[0060] This application controls the thickness of the first adhesive layer 31 to within 0.05mm-0.50mm. On the one hand, this avoids the first adhesive layer 31 being too thin, which would affect its buffering effect. If the first adhesive layer 31 is too thin, its buffering effect will be poor, and there is a risk of microcracks in the solar cell 1 when the insulating structure 3 and the busbar 2 are stacked on it. On the other hand, this avoids the first adhesive layer 31 being too thick, which would affect the overall thickness of the photovoltaic module 100. If the first adhesive layer 31 is too thick, the insulating structure 3 may become thicker, resulting in a thicker area where the busbar 2 and the insulating structure 3 are stacked in the photovoltaic module 100, causing greater surface undulations in the photovoltaic module 100. Therefore, controlling the thickness of the first adhesive layer 31 to within 0.05mm-0.50mm ensures that the first adhesive layer 31 has a buffering effect while preventing the photovoltaic module 100 from becoming too thick.

[0061] Please see Figure 6 In some embodiments, both the first solder strip 4 and the second solder strip 5 extend along a first direction X, and the first direction X is the width direction of the battery cell 1. When the first direction X is the width direction of the battery cell 1, the busbar 2 has a width W1 in the first direction X, and the width of the insulating structure 3 is W2. This satisfies the condition: W2 ≥ W1.

[0062] For example, when the battery cell 1, the insulating structure 3, and the busbar 2 are stacked sequentially along the thickness direction Z of the battery cell 1, the insulating structure 3 is located below the busbar 2. When the width W2 of the insulating structure 3 is greater than or equal to the width W1 of the busbar 2, the insulating structure 3 can completely block the busbar 2 in the first direction X, preventing the busbar 2 from crossing the insulating structure 3 and contacting the battery cell 1, thus preventing a short circuit between the busbar 2 and the battery cell 1.

[0063] Optionally, W1 can be 2mm-15mm and W2 can be 10mm-80mm.

[0064] Understandably, in the first direction X, the width of the insulating structure 3 is set to be wider than the width of the busbar 2 to effectively shield the busbar 2 and prevent it from directly contacting the battery cell 1. For example, when the width W1 of the busbar 2 is 15mm, the width W2 of the insulating structure 3 can be greater than or equal to W1. For example, W2 can be 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm, 55mm, 60mm, 65mm, 70mm, 75mm, 80mm, etc.

[0065] For example, W1 can be 2mm-5mm, 5mm-7mm, 7mm-10mm, 10mm-13mm, 13mm-15mm, etc. For instance, W1 can be 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, or 15mm, etc.

[0066] For example, W2 can be 10mm-20mm, 20mm-30mm, 30mm-40mm, 40mm-50mm, 50mm-60mm, 60mm-70mm, 70mm-80mm, etc. For instance, W2 can be 10mm, 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm, 55mm, 60mm, 65mm, 70mm, 75mm, or 80mm, etc.

[0067] Please see also Figures 6 to 8 In some embodiments, the photovoltaic module 100 further includes a positioning tape 6, which adheres to the second side 2b and the back side 1b to fix the second side 2b to the back side 1b.

[0068] After the busbar 2 is mounted on the back side 1b of the battery cell 1 via the insulating structure 3, the busbar 2 is then positioned and fixed to the back side 1b of the battery cell 1 using the positioning tape 6. This improves the stability of the busbar 2 and further prevents it from slipping.

[0069] Understandably, the material of the positioning tape 6 is also an insulating material.

[0070] Please see Figure 6 In some embodiments, the length of the positioning tape 6 in the first direction X can be L1, satisfying: L1 > W1.

[0071] For example, when L1 > W1, the positioning tape 6 can completely cover the busbar 2 in the first direction X. In this way, when the positioning tape 6 adheres the busbar 2 to the battery cell 1, one end of the positioning tape 6 is adhered to the busbar 2, and the other end is adhered to the battery cell 1. Alternatively, both ends of the positioning tape 6 are adhered to the battery cell 1, and the middle portion of the positioning tape 6 is used to adhere and fix the busbar 2. That is, when the length of the positioning tape 6 is greater than the width of the busbar 2, the positioning tape 6 can span the busbar 2, achieving at least three points of adhesion (at least two points of adhesion between the positioning tape and the battery cell, and then adhesion between the positioning tape and the busbar), thereby more securely fixing the busbar 2.

[0072] Please see also Figures 6 to 8In some embodiments, along the first direction X, the busbar 2 to the edge 11 of the battery cell has a first gap 1c, and the insulating structure 3 extends at least partially into the first gap 1c. The positioning tape 6 includes a first adhesive segment 61, a second adhesive segment 62, and a third adhesive segment 63 connected sequentially along the first direction X. The first adhesive segment 61 extends into the first gap 1c to adhere to the insulating structure 3, the second adhesive segment is adhered to the second surface 2b, and the third adhesive segment 63 is adhered to the back surface 1b.

[0073] It is understandable that when the width of the insulating structure 3 in the first direction X is greater than the width of the busbar 2, and the busbar 2 is spaced apart from the edge 11 of the battery cell in the first direction X to form a first gap 1c, the insulating structure 3 located below the busbar 2 can extend partially to the first gap 1c to prevent the busbar 2 from contacting the back surface 1b of the battery cell 1 at the first gap 1c.

[0074] For example, when part of the insulation structure 3 is located at the first interval 1c, the first adhesive segment 61 of the positioning tape 6 can be adhered to the first interval 1c and adhered to the insulation structure 3, the second adhesive segment 62 can extend along the first direction X to the busbar 2 and adhere to the busbar 2, and the third adhesive segment 63 can extend to the back side 1b of the battery cell 1 and adhere to the battery cell 1.

[0075] In this way, in the first direction X, the positioning tape 6 is respectively attached to the back 1b of the insulating structure 3, the busbar 2 and the battery cell 1, so that the positioning tape 6 can fix the position of the insulating structure 3, the busbar 2 and the battery cell 1 at the same time, which is beneficial to the positioning, installation and fixation of the three.

[0076] Optionally, along the first direction X, the end of the first adhesive segment 61 is close to the edge 11 of the battery cell to be bonded to the insulating structure 3 located at the first interval 1c. The width of the insulating structure 3 is W2, and the length of the positioning tape 6 is L1, satisfying: L1 > W2.

[0077] For example, for insulation protection between the busbar 2 and the battery cell 1, in the first direction X, the width of the insulating structure 3 is greater than the width of the busbar 2, and when one end of the insulating structure 3 is located at the first interval 1c, both ends of the insulating structure 3 in the first direction X extend beyond the edge of the busbar 2, thus shielding the busbar 2. When the end of the first adhesive segment 61 of the positioning tape 6 overlaps with the end of the insulating structure 3, if the length of the positioning tape 6 is less than or equal to the width of the insulating structure 3, the third adhesive segment 63 of the positioning tape 6 will adhere to the insulating structure 3 and will not be able to adhere to the back surface 1b of the battery cell 1. Therefore, when the end of the first adhesive segment 61 is bonded to the end of the insulating structure 3 located at the first interval 1c, the length of the positioning tape 6 needs to be greater than the width of the insulating structure 3 so that the third adhesive segment 63 can adhere to the back surface 1b of the battery cell 1.

[0078] In some embodiments, the insulating structure 3 includes a first adhesive layer 31 and an insulating layer 32 disposed sequentially along the direction from the back surface 1b to the first surface 2a. The first adhesive layer 31 is disposed on the back surface 1b, and the insulating layer 32 is connected to the first surface 2a.

[0079] Of course, in other embodiments, the insulating structure 3 may also consist only of the first adhesive layer 31 and the insulating layer 32, for example, as shown in the example. Figure 9 As shown, the insulating structure 3 and the solar cell 1 are bonded together by the first adhesive layer 31, and the insulating layer 32 insulates the busbar 2 and the solar cell 1. Reducing the amount of the second adhesive layer 33 allows for a reduction in the overall thickness of the insulating structure 3, which in turn helps to reduce the overall thickness of the photovoltaic module 100.

[0080] Therefore, considering the connection stability of the busbar 2, the solution of this application can be adopted by attaching the insulating structure 3, the busbar 2 and the battery cell 1 with the positioning tape 6, or by directly attaching the busbar 2 and the battery cell 1 with the positioning tape 6, so as to fix the busbar 2 and prevent the busbar 2 from slipping.

[0081] Please see Figure 6 In some embodiments, there are multiple first solder strips 4, which are spaced apart along the second direction Y on the back surface 1b of the battery cell 1. The positioning tape 6 is attached to the back surface 1b and located between two adjacent first solder strips 4. Along the second direction Y, the distance between two adjacent first solder strips 4 is d, and the width of the positioning tape 6 is W3, satisfying that d > W3.

[0082] When the positioning tape 6 is attached to the back surface 1b of the battery cell 1, it is placed between the two first solder strips 4. The spacing between the two first solder strips 4 is controlled to be greater than the width of the positioning tape 6, preventing the positioning tape 6 from sticking directly to the first solder strips 4. If the positioning tape 6 sticks directly to the first solder strips 4, air bubbles may form between them due to the protrusion of the first solder strips 4 relative to the back surface 1b of the battery cell 1, potentially causing unstable adhesion of the positioning tape 6.

[0083] Therefore, the positioning tape 6 is pasted between the two first welding strips 4 to prevent the positioning tape 6 from sticking to the first welding strips 4, so that the positioning tape 6 can be stably pasted to the back side 1b of the battery cell 1.

[0084] Please see Figure 10 In some embodiments, the photovoltaic module 100 further includes a backsheet 7 and a spacer strip 8. The spacer strip 8 and the backsheet 7 are stacked sequentially on the second surface 2b. Along the first direction X, the spacer strip 8 covers the busbar 2 and the insulation structure 3.

[0085] Considering that after the insulation structure 3 and busbar 2 are installed on the back side 1b of the battery cell 1, the area on the back side 1b of the battery cell 1 with the insulation structure 3 and busbar 2 will be relatively convex, affecting the flatness of the back side 1b of the battery cell 1, a padding strip 8 is first stacked on the second side 2b of the busbar 2 when installing the back plate 7 on the back side 1b of the battery cell 1. The padding strip 8 covers the busbar 2 and the insulation structure 3 to level the back side 1b of the battery cell 1, thus making the back side 1b of the battery cell 1 relatively flat, so as to facilitate the installation of the back plate 7.

[0086] Optionally, the material of the pad 8 may be an ethylene-vinyl acetate copolymer, i.e., EVA (ethylene-vinylacetate copolymer).

[0087] It is understandable that EVA material has good thermoplasticity, which makes it easy to bond the second side 2b to the back plate 7 after heating.

[0088] Please see also Figures 6 to 8 as well as Figure 11 In some embodiments, after the busbar 2 is folded to the back surface 1b of the battery cell 1 for connection, the extension segment 51 connected to the busbar 2 will also be bent accordingly. The extension segment 51 includes a first sub-segment 511, a bent segment 512, and a second sub-segment 513. The first sub-segment 511 is located on the front surface 1a of the battery cell 1, and the second sub-segment 513 is connected to the second surface 2b. Along the thickness direction Z of the battery cell 1, the second sub-segment 513 is at least partially offset from the first sub-segment 511, and a portion of the padding strip 8 is stacked on the second sub-segment 513.

[0089] On the one hand, when setting the extension segment 51, this application makes the extension segment 51 protrude entirely from the edge 11 of the battery cell, so that the bending segment 512 of the extension segment 51 bends away from the battery cell 1, avoiding bending the bending segment 512 close to the edge 11 of the battery cell, which would cause the bending radius of the bending segment 512 to be too large, thus causing the connection between the extension segment 51 and the edge 11 of the battery cell to peel off and damage the battery cell 1. Therefore, by setting the bending segment 512 away from the edge 11 of the battery cell through the first sub-segment 511 and the second sub-segment 513, the bending radius of the bending segment 512 is reduced, so that the extension segment 51 can bend while avoiding damage to the battery cell 1.

[0090] On the other hand, the first sub-segment 511 and the second sub-segment 513 are staggered in the thickness direction Z of the cell 1, which can also disperse the stress in the first solder strip 4 and prevent the first solder strip 4 from peeling off from the cell 1 and causing damage to the cell 1.

[0091] Optionally, along the first direction X, the first sub-segment 511 is inclined relative to the second solder strip 5, and the second sub-segment 513 is inclined relative to the first solder strip 4, and the inclination directions of the first sub-segment 511 and the second sub-segment 513 intersect.

[0092] When setting the pad strip 8, some of the pad strip 8 is overlapped on the second sub-segment 513. The pad strip 8 has a certain degree of adhesiveness. When the pad strip 8 is pasted onto the second sub-segment 513, air bubbles will form between the pad strip 8 and the second sub-segment 513. By tilting the second sub-segment 513, the air bubbles can be discharged along the tilted second sub-segment 513, so that the pasting position of the pad strip 8 and the second sub-segment 513 fits better, so as to keep the pad strip 8 flat and facilitate the setting of the back plate 7.

[0093] In some embodiments, the bent segment 512 is configured as an arc segment, the bent segment 512 having an arc vertex, the distance between the arc vertex and the edge 11 of the battery cell being L2, where L2 is 1mm-3mm.

[0094] For example, L2 can be 1mm-1.5mm, 1.5mm-2mm, 2mm-2.5mm, 2.5mm-3mm, etc. For instance, L2 can be 1mm, 1.3mm, 1.5mm, 1.7mm, 2mm, 2.3mm, 2.5mm, 2.7mm, or 3mm, etc.

[0095] By setting the lengths of the first sub-segment 511 and the second sub-segment 513 protruding from the edge 11 of the battery cell, the arc point of the bending segment 512 is made far away from the edge 11 of the battery cell. This avoids the bending segment 512 being too close to the battery cell 1, preventing stress concentration at the connection between the battery cell 1 and the extension segment 51 when the bending segment 512 is bent, which could lead to damage to the battery cell 1.

[0096] Please see Figure 12 In some embodiments, a buffer space 51a is formed between the first segment 511, the bent segment 512 and the second segment 513, and the insulating structure 3 extends at least partially into the buffer space 51a.

[0097] For example, after the extension 51 is bent, the first sub-segment 511, the bent segment 512 and the second sub-segment 513 form a buffer space 51a. Part of the insulating structure 3 extends into the buffer space 51a to shield the busbar 2, so as to prevent the busbar 2 from crossing the edge of the insulating structure 3 and coming into contact with the battery cell 1 and causing a short circuit.

[0098] Moreover, after the insulation structure 3 extends to the buffer space 51a, the first adhesive layer 31 contacts the first sub-segment 511, and the second adhesive layer 33 contacts the second sub-segment 513. The flexible first adhesive layer 31 and the second adhesive layer 33 can provide buffer for the first sub-segment 511 and the second sub-segment 513, which is beneficial to protect the extension segment 51.

[0099] The photovoltaic modules disclosed in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the photovoltaic modules and their core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A photovoltaic module, characterized in that, include: A solar cell, the solar cell including a front side and a back side along its thickness direction; A busbar, the busbar including a first surface and a second surface along the thickness direction of the battery cell, the busbar being disposed on the back side, and the first surface being close to the back side; An insulating structure is located between the back surface and the first surface. The insulating structure includes a first adhesive layer, an insulating layer, and a second adhesive layer sequentially disposed along the direction from the back surface to the first surface. The first adhesive layer is disposed on the back surface, and the second adhesive layer is connected to the first surface. A first solder strip is disposed on the back side, and a first adhesive layer is disposed on at least a portion of the first solder strip corresponding to the busbar. The second solder strip is disposed on the front side and extends at least partially beyond the edge of the cell to form an extension, which is bent along the thickness direction of the cell to the back side to connect to the second surface.

2. The photovoltaic module according to claim 1, characterized in that, The first adhesive layer is an ethylene-vinyl acetate copolymer; and / or, The insulating layer is made of polyethylene terephthalate or polyolefin; and / or... The second adhesive layer is an ethylene-vinyl acetate copolymer.

3. The photovoltaic module according to claim 1, characterized in that, The thickness of the second adhesive layer is h1, the thickness of the insulating layer is h2, and the thickness of the first adhesive layer is h3; Satisfying: h3 > h1; and / or, The h1 is 0.01mm-0.15mm; and / or, The h2 is 0.01mm-0.15mm; and / or, The h3 is 0.05mm-0.50mm.

4. The photovoltaic module according to any one of claims 1-3, characterized in that, Both the first solder strip and the second solder strip extend along a first direction, which is the width direction of the battery cell; Along the first direction, the width of the busbar is W1, and the width of the insulation structure is W2; The W1 is 2mm-15mm, and the W2 is 10mm-80mm; and / or, W2 ≥ W1.

5. The photovoltaic module according to any one of claims 1-3, characterized in that, The photovoltaic module also includes a positioning tape, which adheres to the second side and the back side.

6. The photovoltaic module according to claim 5, characterized in that, Both the first solder strip and the second solder strip extend along a first direction, which is the width direction of the battery cell; Along the first direction, the width of the busbar is W1, and the length of the positioning tape is L1, satisfying: L1 > W1.

7. The photovoltaic module according to claim 5, characterized in that, Both the first solder strip and the second solder strip extend along a first direction, which is the width direction of the battery cell; Along the first direction, the busbar has a first interval to the edge of the battery cell, and the insulating structure extends at least partially into the first interval; The positioning tape includes a first adhesive segment, a second adhesive segment, and a third adhesive segment connected sequentially along the first direction. The first adhesive segment extends into the first interval to adhere to the insulating structure, the second adhesive segment adheres to the second surface, and the third adhesive segment adheres to the back surface.

8. The photovoltaic module according to claim 7, characterized in that, Along the first direction, the end of the first adhesive segment is close to the edge of the battery cell to adhere to the insulating structure located at the first interval. The width of the insulating structure is W2, and the length of the positioning tape is L1, satisfying: L1 > W2.

9. The photovoltaic module according to claim 5, characterized in that, Both the first solder strip and the second solder strip extend along a first direction, which is the width direction of the battery cell; The first welding strip consists of multiple strips, which are spaced apart along the second direction on the back side. The positioning tape is attached to the back side and located between two first welding strips. Along the second direction, the spacing between two adjacent first solder strips is d, and the width of the positioning tape is W3, satisfying: d > W3; Wherein, the second direction is the length direction of the battery cell.

10. The photovoltaic module according to any one of claims 1-3, characterized in that, The photovoltaic module also includes a backsheet and a spacer strip, wherein the spacer strip and the backsheet are stacked sequentially on the second surface, and along the first direction, the spacer strip covers the busbar and the insulation structure; Wherein, the first direction is the width direction of the battery cell.

11. The photovoltaic module according to claim 10, characterized in that, The extension section includes a first sub-segment, a bent segment, and a second sub-segment connected in sequence. The first sub-segment is located on the front side of the battery cell, and the second sub-segment is connected to the second side. Along the thickness direction of the battery cell, the second sub-segment is at least partially offset from the first sub-segment, and part of the padding strip is stacked on the second sub-segment.

12. The photovoltaic module according to claim 11, characterized in that, Along the first direction, the first sub-segment is inclined relative to the second solder strip, the second sub-segment is inclined relative to the first solder strip, and the inclination directions of the first sub-segment and the second sub-segment intersect.

13. The photovoltaic module according to any one of claims 1-3, characterized in that, The extension segment includes a first sub-segment, a bent segment, and a second sub-segment connected in sequence. The first sub-segment is connected to the second welding strip, and the second sub-segment is connected to the second surface. The bent segment is constructed as an arc segment with an arc vertex. The distance between the arc vertex and the edge of the battery cell is L2, where L2 is 1mm-3mm.

14. The photovoltaic module according to claim 13, characterized in that, A buffer space is formed between the first sub-segment, the bent segment, and the second sub-segment, and the insulating structure extends at least partially into the buffer space.

15. A photovoltaic module, characterized in that, include: A solar cell, the solar cell including a front side and a back side along its thickness direction; A busbar, the busbar including a first surface and a second surface along the thickness direction of the battery cell, the busbar being disposed on the back side, and the first surface being close to the back side; An insulating structure is located between the back surface and the first surface. The insulating structure includes a first adhesive layer and an insulating layer sequentially disposed along the direction from the back surface to the first surface. The first adhesive layer is disposed on the back surface, and the insulating layer is connected to the first surface. A first solder strip is disposed on the back side, and a first adhesive layer is disposed on at least a portion of the first solder strip corresponding to the busbar. The second solder strip is disposed on the front side and extends at least partially beyond the edge of the cell to form an extension, which is bent along the thickness direction of the cell to the back side to connect to the second surface.

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