A solar cell, a solar cell string, and a photovoltaic module

Abstract

This application discloses a solar cell, a solar cell string, and a photovoltaic module. The solar cell includes: a cell; an electrode disposed on the back of the cell, the electrode including a main grid and a sub-grid; and an insulating component including a first insulating adhesive segment and a second insulating adhesive segment. The first insulating adhesive segment is disposed on both sides of the main grid along a second direction, and the second insulating adhesive segment covers the end of the sub-grid, which is spaced apart from the main grid, along a first direction. The first insulating adhesive segment is bonded to at least two adjacent second insulating adhesive segments to form a U-shaped area. The first direction intersects the second direction. The above-mentioned insulating adhesive graphic design places the solder pads within the U-shaped area formed by the bonding of the first and second insulating adhesive segments. The U-shaped insulating adhesive wraps around the solder joint, resulting in a higher morphology of the conductive material after printing, making it less prone to flow and collapse, and ensuring closer contact with the solder ribbon, reducing the risk of puncture, cold solder joint, and misalignment.

Description

Technical Field

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

[0002] Solar energy is an inexhaustible renewable energy source for humankind. Photovoltaic modules are the core and most important component of a solar power generation system. Their function is to convert solar energy into electrical energy, which is then stored in batteries or used to power loads. A photovoltaic module typically includes a front-side encapsulation structure, a back-side encapsulation structure, and a cell array. The cell array consists of multiple cell strings connected in series or parallel. Each cell string includes multiple spaced-apart cells, with adjacent cells connected by solder strips.

[0003] Currently manufactured solar cells utilize insulating adhesive to prevent short circuits between the grid lines and solder ribbons. Existing insulating adhesive technologies mainly fall into two categories: full coverage of the sub-grids and partial coverage of sub-grids of the same polarity. While full coverage of all sub-grids provides better insulation, it negatively impacts bifaciality and efficiency, and also increases printing costs. Partial coverage of sub-grids of the same polarity makes it difficult to control the solder paste morphology and increases the risk of solder paste punctures and leakage. Furthermore, although insulating adhesive is applied to the grid lines, short circuits still occur. Summary of the Invention

[0004] The purpose of this application is to overcome the problems existing in the prior art and to provide a solar cell, a solar cell string, and a photovoltaic module.

[0005] The technical problem solved by this application is achieved by the following technical solution.

[0006] This application provides a solar cell, comprising: Battery cells; An electrode disposed on the back of the battery cell includes a main grid and a sub-grid. The main grid includes a first main grid and a second main grid that are alternately distributed along a first direction. The sub-grid includes a first sub-grid and a second sub-grid that are alternately distributed along a second direction. The first sub-grid and the second main grid are spaced apart, and the second sub-grid and the first main grid are spaced apart. An insulating component, comprising a first insulating adhesive segment and a second insulating adhesive segment, wherein the first insulating adhesive segment is disposed on both sides of the main grid along a second direction, and the second insulating adhesive segment covers the end of the sub-grid disposed at a distance from the main grid along a first direction, and the first insulating adhesive segment is bonded to at least two adjacent second insulating adhesive segments to form a U-shaped area; The first direction intersects with the second direction.

[0007] In some embodiments of this application, it further includes: a pad, which is disposed on the main gate and located within the area where the first insulating adhesive segment and the second insulating adhesive segment are bonded together to form a U-shape.

[0008] In some embodiments of this application, the pads are square or rhomboid.

[0009] In some embodiments of this application, the height of the first insulating adhesive segment and / or the second insulating adhesive segment is 10-300 μm.

[0010] In some embodiments of this application, a plurality of solder strips are also included, the plurality of solder strips being spaced apart along the length direction of the sub-gate, each solder strip extending along the length direction of the main gate, and each solder strip being connected to the corresponding main gate through a plurality of solder pads.

[0011] In some embodiments of this application, the spacing between the two first insulating segments on opposite sides is greater than the width of the welding strip, and preferably the width of the first insulating segment is 0.5mm-3mm.

[0012] In some embodiments of this application, the width of the second insulating adhesive segment is 10-500 μm.

[0013] In some embodiments of this application, a conductive material is also included, which is disposed on the pad body and is used to fill the height difference between the solder strip and the pad.

[0014] In some embodiments of this application, the conductive material includes at least one of conductive adhesive and conductive paste; and / or, the material of the conductive material includes at least one of tin-lead alloy, bismuth-containing solder paste, and silver-containing solder paste.

[0015] This application also provides a solar cell string, which includes: a plurality of solar cells having the above-described electrode structure, wherein the plurality of solar cells are connected by solder strips to form the solar cell string.

[0016] This application also provides a photovoltaic module, which includes the aforementioned solar cell or solar cell string.

[0017] This application has the following beneficial effects: This application provides a solar cell, a solar cell string, and a photovoltaic module. In this application, insulating adhesive is printed on the grid lines. The U-shaped area formed by the insulating adhesive surrounds the solder pads. After the adhesive in the U-shaped area solidifies, it acts as a wall to restrict the irregular movement of conductive materials, making the height and roundness of conductive materials such as solder paste more fixed, and making the contact with the solder strip tighter, reducing the risk of puncture, cold solder joints, and misalignment. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is one of the structural schematic diagrams of a solar cell provided in the embodiments of this application; Figure 2 This is a second schematic diagram of the structure of a solar cell provided in an embodiment of this application; Figure 3 This is the third schematic diagram of a solar cell structure provided in the embodiments of this application; Figure 4 This is the fourth schematic diagram of a solar cell structure provided in the embodiments of this application; Figure numbers: Cell-100, Electrode-200, Main busbar-210, First main busbar-211, Second main busbar-212, Sub-busbar-220, First sub-busbar-221, Second sub-busbar-222, First disconnection area-230, Second disconnection area-240, Insulator-300, First insulating adhesive segment-310, Second insulating adhesive segment-320, Pad-400, Solder ribbon-500, First solder ribbon-510, Second solder ribbon-520. Detailed Implementation

[0020] 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.

[0021] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" 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 device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0022] 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.

[0023] 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.

[0024] The technical solutions provided in this application will be further described below with reference to the embodiments and accompanying drawings.

[0025] This application provides a solar cell, such as... Figure 1 As shown, the solar cell includes: a cell 100, an electrode 200, an insulating component 300, a solder pad 400, a solder ribbon 500, and a conductive material.

[0026] The solar cell 100 is made of silicon wafer. The solar cell 100 is used to absorb solar energy and convert solar energy into electrical energy. The specific structure and principle of the solar cell 100 are existing technologies and will not be described in detail here. The back of the solar cell 100 is provided with electrodes 200, which include main grids 210 and sub-grids 220, and there are multiple main grids 210 and sub-grids 220. The main grid 210 includes a first main grid 211 and a second main grid 212 alternately distributed along a first direction, and both the first main grid 211 and the second main grid 212 extend along a second direction. The sub-grids 220 include a first sub-grid 221 and a second sub-grid 222 alternately distributed along a second direction, and both the first sub-grid 221 and the second sub-grid 222 extend along the first direction, and are used to collect and guide the photocurrent generated in the solar cell 100. The first sub-grid 221 intersects with the first main grid 211 and forms an electrical connection, so that the first main grid 211 can collect and output the photocurrent collected by the first sub-grid 221. The second sub-grid 222 intersects with the second main grid 212 and forms an electrical connection, so that the second main grid 212 can collect and output the photocurrent collected by the second sub-grid 222.

[0027] It should be noted that the X direction is the first direction, the Y direction is the second direction, and the first direction intersects with the second direction, such as... Figure 1 As shown, one of the first direction and the second direction can be the length direction of the solar cell, and the other can be the width direction of the solar cell.

[0028] In this embodiment, the first main gate 211 and the second main gate 212 have opposite polarities, the first sub-gate 221 and the second sub-gate 222 have opposite polarities, and the first main gate 211 and the first sub-gate 221 have the same polarity, while the second main gate 212 and the second sub-gate 222 have the same polarity. For example, the first main gate 211 is the positive main gate, the second main gate 212 is the negative main gate, the first sub-gate 221 is the positive sub-gate, and the second sub-gate 222 is the negative sub-gate. The first sub-gate 221 and the second main gate 212 are spaced apart, meaning the first sub-gate 221 is disconnected at the second main gate 212 to form a first disconnection region 230, to prevent the first sub-gate 221 from being electrically connected to the second main gate 212 and short-circuiting. The second sub-gate 222 and the first main gate 211 are spaced apart, meaning the second sub-gate 222 is disconnected at the first main gate 211 to form a second disconnection region 240, to prevent the second sub-gate 222 from being electrically connected to the first main gate 211 and short-circuiting.

[0029] Since the first sub-gate 221 and the second sub-gate 222 are arranged alternately along the first direction, this staggered layout poses a short-circuit risk. To address this, this application provides a first disconnection region 230 at the location of the first sub-gate 221 corresponding to the second main gate 212, and a second disconnection region 240 at the location of the second sub-gate 222 corresponding to the first main gate 211.

[0030] The first sub-gate 221 is broken at the corresponding second main gate 212. The broken area is the second break region 240. The first sub-gate 221 is divided into two parts, located on both sides of the second main gate 212. That is, a first segment located on the first side of the first main gate 211 and a second segment located on the second side of the first main gate 211. This break creates a predetermined distance between the second sub-gate 222 and the first main gate 211.

[0031] After the first sub-gate 221 is provided with a first disconnection area 230 at the second main gate 212, there is a preset distance between the first sub-gate 221 and the second main gate 212. The first sub-gate 221 is only electrically connected to the first main gate 211 and not electrically connected to the second main gate 212. The second sub-gate 222 is disconnected at the first main gate 211 to form the first disconnection area 230. The second sub-gate 222 is only electrically connected to the second main gate 212 and not electrically connected to the first main gate 211.

[0032] The second auxiliary gate 222 is disconnected at the corresponding location of the first main gate 211. This disconnected area is the second disconnection area 240. The second auxiliary gate 222 is divided into two parts, located on both sides of the first main gate 211. That is, the first auxiliary gate 222 is divided into two parts, located on both sides of the second main gate 211. Specifically, there is a first segment located on the first side of the first main gate 211 and a second segment located on the second side of the first main gate 211. This disconnection creates a predetermined distance between the second auxiliary gate 222 and the first main gate 211.

[0033] like Figure 2As shown, when the first solder strip 510 is disposed on the first main gate 211 along the second direction, the first solder strip 510 does not contact the second sub-gate 222, and there will be no problem of short circuit caused by the first solder strip 510 and the second sub-gate 222 being conductive. When the second solder strip 520 is disposed on the second main gate 212 along the second direction, the second solder strip 520 does not contact the first sub-gate 221, and there will be no problem of short circuit caused by the second solder strip 520 and the first sub-gate 221 being conductive.

[0034] It is understandable that although the first disconnection zone 230 and the second disconnection zone 240 described above can reduce the risk of short circuits caused by contact with the secondary grid 220 which is spaced apart from the main grid 210, since the solder ribbon 500 is connected to the pad 400 through a conductive material, the conductive material on the pad 400 will overflow and diffuse during the lamination process. If the conductive material diffuses to areas outside the first disconnection zone 230 and the second disconnection zone 240, it will come into contact with grid lines of different polarities, resulting in a short circuit. In order to avoid short circuits caused by the solder ribbon 500 coming into contact with the secondary grid 220 located on both sides of the main grid 210 and having the opposite polarity to the main grid 210, the solar cell provided in this embodiment also includes an insulating component to form an insulating effect between the main grid 210 and the secondary grid 220 with opposite polarities. The following description uses insulating adhesive as an example of the insulating component.

[0035] Combination Figures 1-4 As shown, the insulating component 300 includes a first insulating adhesive segment 310 and a second insulating adhesive segment 320. The first insulating adhesive segment 310 is disposed on both sides of the main grid 210 along a second direction, and the second insulating adhesive segment 320 covers the end of the sub-grid 220 disposed at intervals from the main grid 210 along a first direction. The first insulating adhesive segment 310 is bonded to at least two adjacent second insulating adhesive segments 320 to form a U-shaped area. A solder pad 400 is disposed in the U-shaped area. When the solder pad 400 is connected to the solder ribbon 500, a conductive material is applied to the solder pad 400 in the U-shaped area. The wall formed by the adhesive in the U-shaped area makes the conductive material have a higher morphology after printing and is not easy to flow or collapse. After the colloid in the U-shaped area solidifies, it acts as a wall, restricting the irregular movement of conductive materials. This makes the height and roundness of conductive materials such as solder paste more consistent, resulting in a higher contact area between the conductive material and the pads 400 and solder ribbons 500. This allows the material to effectively fill the space between the pads 400 and solder ribbons 500, ensuring the stability of the connection between them. Furthermore, the wall formed by the solidified colloid in the U-shaped area prevents solder paste from flowing onto the connection area between the pads 400 and the main grid 210, further improving the connection stability between the pads 400 and the main grid 210 and enhancing the current collection efficiency of the solar cell string.

[0036] During the connection of pads 400 and ribbons 500 on the main grid 210, local high points are formed due to the thickness of the pads 400 and the presence of conductive material on their surface. After the ribbons 500 are laid, the corresponding positions on the pads 400 are raised, forming local suspensions or stress concentration points, increasing the bending curvature of the ribbons 500. This non-uniform deformation not only easily leads to open or poorly soldered connections at the welding interface, but also introduces additional mechanical stress to the silicon substrate during cooling due to the mismatch in thermal expansion coefficients, inducing warping or even microcracks in the solar cells, ultimately resulting in a decrease in the photoelectric conversion efficiency of the cell 100 and the yield of the module. In this embodiment, a second insulating adhesive segment 320 is printed at the end of the sub-gate 220, which is spaced apart from the main gate 210. At least a portion of the second insulating adhesive segment 320 covers the surface of the main gate 210, providing a support interface during the laying of the solder ribbon 500 to compensate for the height difference between the corresponding part of the solder pad 400 and other adjacent parts, making the conductive material in closer contact with the solder ribbon 500 and reducing the risk of puncture, poor soldering, and misalignment. Along the first direction, multiple second insulating adhesive segments 320 uniformly distribute the force on the solder ribbon 500. The above structural design improves the welding tensile strength by reducing the local bending degree of the solder ribbon 500, reducing the risk of grid line breakage and cell warping, thereby improving the reliability and yield of the solar cell.

[0037] The first insulating adhesive segments 310 disposed on both sides of the main grid 210 along the second direction can prevent the solder ribbon 500 connected to the main grid 210 from contacting the end of the sub-grid 220 at the break point and forming an electrical connection with the sub-grid 220. This reduces the risk of short circuits in the solar cell caused by solder ribbon 500 misalignment, which is beneficial to improving the structural reliability of the solar cell and also to improving the yield of photovoltaic modules. In addition, when the first insulating adhesive segments 310 are coated on at least two opposite sides of the solder ribbon 500, the solder ribbon 500 and the first insulating adhesive segments 310 are adhered and sealed, which can prevent the penetration of the encapsulation film.

[0038] In addition, an electrode structure is provided on the solar cell, and then insulating adhesive is printed on the electrode structure to form a U-shaped insulating component 300. The height of the first insulating adhesive segment 310 and the second insulating adhesive segment 320 forming the insulating component 300 is 10-300μm, while the height of the pad 400 is usually 3-15μm. The U-shaped insulating component 300 formed by bonding the first insulating adhesive segment 310 and the second insulating adhesive segment 320 forms a closed wall around the pad 400. Usually, the height of the insulating component 300 is controlled to be higher than the height of the pad 400. The height difference between the pad 400 and the insulating component 300 is filled with a conductive material, which can also improve the tightness and effectiveness of the welding between the solder ribbon 500 and the pad 400. For example, the conductive material includes at least one of conductive adhesive and conductive paste. Specifically, the conductive adhesive uses an adhesive to connect the solder ribbon 500 to the solder pad 400 body, resulting in a high degree of tightness between the solder ribbon 500 and the solder pad 400 body, thereby improving the connection stability of the solar cell string. The conductive paste uses a metal welding method to connect the solder ribbon 500 to the solder pad 400 body. During the welding process, the metal melts, thereby connecting the solder ribbon 500 to the solder pad 400. This material has a low production cost, which helps to reduce the cost of production and processing.

[0039] In this embodiment, the spacing between the two first insulating adhesive segments 310 on opposite sides is greater than the width of the solder strip 500.

[0040] As the requirements for photoelectric conversion efficiency of photovoltaic modules become increasingly stringent, the width of the solder ribbon 500 is becoming narrower, and the contact area between the solder ribbon 500 and the pad 400 is becoming smaller. Therefore, if some encapsulating film permeates between the pad 400 and the solder ribbon 500, it can easily lead to desoldering. Therefore, the spacing between the two first insulating adhesive segments 310 printed on opposite sides of the main grid 210 is greater than or equal to the width of the solder ribbon 500. This allows the solder ribbon 500 to adhere and seal with the first insulating adhesive segment 310 after the photocurable or thermocurable adhesive has cured, preventing the permeation of the encapsulating film.

[0041] Furthermore, the spacing between the two first insulating adhesive segments 310 on opposite sides is greater than the width of the solder ribbon 500. After the photocurable or thermocurable adhesive has cured, even if the solder paste flows or is squeezed to some extent during the soldering process, the insulating adhesive can still form a complete physical barrier between the edge of the solder ribbon 500 and the opposite polarity sub-gate. The molten solder paste is blocked before reaching the edge of the insulating adhesive and cannot contact the exposed opposite polarity electrode, fundamentally eliminating the leakage path. At the same time, the spacing between the two first insulating adhesive segments 310 on opposite sides is greater than the width of the solder ribbon 500. Even if the solder ribbon 500 deviates slightly during the laying process, as long as its edge is still within the coverage area of ​​the insulating adhesive, it will not touch the opposite polarity sub-gate, reducing the requirements for mounting accuracy and improving production efficiency.

[0042] In some embodiments, the width of the first insulating adhesive segment is preferably 0.5mm-3mm.

[0043] In some embodiments, the width of the second insulating adhesive segment 320 is 10-500 μm. It should be noted that the width of the second insulating adhesive segment 320 is not too small, ensuring that it can cover the end of the sub-gate 220 to improve its insulation effect. The width of the second insulating adhesive segment 320 is not too large, which saves insulating adhesive material and reduces the risk of warping of the solar cell due to volume shrinkage during curing.

[0044] In other embodiments, the second insulating adhesive segment 320 has a structure that is narrow in the middle and wide at both ends. This reduces the amount of insulating adhesive used, which helps to reduce the manufacturing cost of the solar cell. On the other hand, when the second insulating adhesive segment 320 is configured as narrow in the middle and wide at both ends, firstly, the width of the insulating adhesive covering the break in the sub-gate 220 is larger, which can better cover the sub-gate 220 and prevent the insulating adhesive covering the ends of the sub-gate 220 from shifting and exposing the sub-gate 220; in summary, the insulating adhesive covering the ends of the sub-gate 220 is the area that is closer to the solder ribbon 500, and is the area that is more likely to short-circuit with the solder ribbon 500. The larger width of the insulating adhesive covering the ends of the sub-gate 220 is beneficial to improving the insulation effect.

[0045] In some embodiments, the insulating adhesive is applied using screen printing / inkjet printing. Figure 4 The morphology of the material is covered on the metal grid area on the back of the finished cell. After the insulating adhesive is applied, it is cured by light curing or heating in an oven according to the characteristics of the insulating adhesive (light curing adhesive / thermosetting adhesive). This allows the adhesive to isolate the P / N area on the back of the cell, thereby ensuring that the current in the grid can be led out using solder ribbon without short-circuiting and affecting the power conversion of the module.

[0046] This application also provides a battery assembly that includes the solar cells provided in any embodiment of this application and has corresponding beneficial effects.

[0047] Specifically, the battery module may include multiple solar cells, which can be connected in series to form a battery string. The battery strings can be connected in series, in parallel, or in a series-parallel combination to achieve current output. For example, the connection between individual battery cells 100 can be achieved by welding the welding strip 500, and the connection between individual battery strings can be achieved by busbars.

[0048] The battery module may also include a metal frame, a backsheet, photovoltaic glass, and an encapsulating film. The encapsulating film can be filled between the light-facing side of the solar cell and the photovoltaic glass, the back-facing side and the backsheet, and adjacent cells 100, etc. As a filler, it can be a transparent colloid with good light transmittance and aging resistance. For example, the encapsulating film can be EVA (ethylene-vinyl acetate copolymer) film or POE (ethylene-α-olefin copolymer) film. The specific choice can be made according to the actual situation and is not limited here.

[0049] Photovoltaic glass can be applied to the encapsulating film on the light-facing side of a solar cell. This photovoltaic glass can be ultra-clear glass, possessing high light transmittance, high transparency, and superior physical, mechanical, and optical properties. For example, ultra-clear glass can achieve a light transmittance of over 92%, protecting the solar cell while minimizing impact on its efficiency. Simultaneously, the encapsulating film bonds the photovoltaic glass and the solar cell together, providing sealing, insulation, and waterproofing / moisture protection for the solar cell.

[0050] A backsheet is attached to the encapsulating film on the back side of the solar cell. The backsheet protects and supports the solar cell, providing reliable insulation, water resistance, and aging resistance. Multiple backsheet options are available, typically including tempered glass, acrylic glass, and aluminum alloy TPT composite encapsulating film. The backsheet, solar cell, encapsulating film, and photovoltaic glass together form a single unit mounted on a metal frame. The metal frame serves as the primary external support structure for the entire solar module, providing stable support and installation. For example, the solar module can be installed at the desired location using the metal frame.

[0051] This application also provides a photovoltaic system, which includes the battery module as provided in any embodiment of this application and has corresponding beneficial effects.

[0052] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A solar cell, characterized in that, include: Battery cell (100); An electrode (200) disposed on the back side of the battery cell (100) includes a main grid (210) and a sub-grid (220). The main grid (210) includes a first main grid (211) and a second main grid (212) alternately distributed along a first direction. The sub-grid (220) includes a first sub-grid (221) and a second sub-grid (222) alternately distributed along a second direction. The first sub-grid (221) and the second main grid (212) are spaced apart, and the second sub-grid (222) and the first main grid (211) are spaced apart. An insulating component (300) includes a first insulating adhesive segment (310) and a second insulating adhesive segment (320). The first insulating adhesive segment (310) is disposed on both sides of the main grid (210) along a second direction, and the second insulating adhesive segment (320) covers the end of the sub-grid (220) which is spaced apart from the main grid (210) along a first direction. The first insulating adhesive segment (310) is bonded to at least two adjacent second insulating adhesive segments (320) to form a U-shaped area. The first direction intersects with the second direction.

2. The solar cell according to claim 1, characterized in that, Also includes: The pad (400) is disposed on the main gate (210) and located in the area where the first insulating adhesive segment (310) and the second insulating adhesive segment (320) are bonded together to form a U-shaped area. Preferably, the pad (400) is square or rhomboid.

3. The solar cell according to claim 2, characterized in that, The height of the first insulating adhesive segment (310) and / or the second insulating adhesive segment (320) is 10-300 μm.

4. The solar cell according to claim 1, characterized in that, It also includes a plurality of solder strips (500), which are spaced apart along the length of the sub-gate (220), each solder strip (500) extending along the length of the main gate (210), and each solder strip (500) being connected to the corresponding main gate (210) through a plurality of pads (400).

5. The solar cell according to claim 4, characterized in that, The spacing between the two first insulating adhesive segments (310) on opposite sides is greater than the width of the welding strip (500), and preferably the width of the first insulating adhesive segment (310) is 0.5mm-3mm.

6. The solar cell according to claim 4, characterized in that, The width of the second insulating adhesive segment (320) is 10-500 μm.

7. The solar cell according to claim 4, characterized in that, It also includes a conductive material disposed on the pad (400) and the conductive material is used to fill the height difference between the solder strip (500) and the pad (400).

8. The solar cell according to claim 7, characterized in that, The conductive material includes at least one of conductive adhesive and conductive paste; and / or, the material of the conductive material includes at least one of tin-lead alloy, bismuth-containing solder paste, and silver-containing solder paste.

9. A solar cell string, characterized in that, include: A plurality of solar cells having the electrode (200) structure of any one of claims 1-8, wherein the plurality of solar cells are connected by solder strips (500) to form the solar cell string.

10. A photovoltaic module, characterized in that, include: The solar cell according to any one of claims 1 to 8, or the solar cell string according to claim 9.

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