Cell string and photovoltaic module

Abstract

The present application belongs to the technical field of photovoltaics. Disclosed are a cell string and a photovoltaic module. The cell string comprises: cells, wherein each cell comprises a substrate, and a plurality of first doped layers and a plurality of second doped layers that are formed on a first surface of the substrate, the first doped layers and the second doped layers both extend in a first direction and are alternately distributed in a second direction, there is a first spacing region between every adjacent first doped layer and second doped layer, a first fine grid is provided on each first doped layer, a second fine grid is provided on each second doped layer, the first fine grids and the second fine grids both extend in the first direction, and the second direction intersects the first direction; and first connecting members, which extend in the second direction and are connected to the first fine grids, wherein in a first region of the first surface, a plurality of second insulating blocks corresponding to the second fine grids on a one-to-one basis are provided at intersections of the first connecting members and the second fine grids, and in the second direction, at least some of the second insulating blocks extend to the first spacing regions adjacent thereto.

Description

A battery string and photovoltaic module

[0001] This application claims priority to Chinese Patent Application No. 202410924414.7, filed on July 11, 2024, entitled “A Battery String and Photovoltaic Module”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of photovoltaic technology, and in particular to a battery string and a photovoltaic module. Background Technology

[0003] Solar cells are the core component of photovoltaic modules, converting solar energy into electrical energy. Back-contact solar cells have both the positive and negative grid lines located on the back of the cell to prevent them from obstructing the front, thus improving photoelectric conversion efficiency. Gridless back-contact solar cells, on the other hand, only have fine positive and negative grids on the back, without a main grid. Solder ribbons are connected to these grids to collect the current and transmit it to the external circuitry.

[0004] In related technologies, the positive and negative grids of a gridless back-contact solar cell both extend along a first direction and are arranged alternately along a second direction. That is, along the second direction, a positive grid has a negative grid on each side. Taking the connection of the solder ribbon to the positive grid as an example, a bonding layer is provided at the connection point between the positive grid and the solder ribbon to improve the reliability of the connection. An insulating layer is provided between the negative grid and the solder ribbon to prevent short circuits in the solar cell.

[0005] However, the above configuration makes it easy for the bonding layer material to overflow into the gap between the positive electrode grid and the adjacent negative electrode grid, resulting in leakage in the photovoltaic module.

[0006] Application content

[0007] This application aims to provide a battery string and photovoltaic module to solve, or at least partially solve, the problem in the prior art where bonding layer material easily overflows into the gap between the positive electrode grid and the adjacent negative electrode grid, causing leakage in the photovoltaic module.

[0008] In a first aspect, this application discloses a battery string, the battery string comprising: a battery cell, the battery cell including a substrate and a plurality of first doped layers and a plurality of second doped layers forming a first surface of the substrate, the first doped layers and the second doped layers both extending along a first direction and alternately arranged along a second direction, a first gap region being formed between adjacent first doped layers and second doped layers, a first fine grid being disposed on the first doped layer, a second fine grid being disposed on the second doped layer, the first fine grid and the second fine grid both extending along the first direction, the second direction intersecting the first direction; a first connector, the first connector extending along the second direction, the first connector being connected to the first fine grid, and in a first region of the first surface, a plurality of second insulating blocks corresponding one-to-one with the second fine grid are disposed at the intersection of the first connector and the second fine grid, and at least a portion of the second insulating blocks extending into the adjacent first gap region along the second direction.

[0009] Secondly, this application also discloses a photovoltaic module, which includes the battery string described in the first aspect.

[0010] This application discloses a battery string and a photovoltaic module. The battery string includes battery cells, each battery cell including a substrate forming a plurality of first doped layers and a plurality of second doped layers on a first surface of the substrate. The first doped layers and the second doped layers both extend along a first direction and are alternately arranged along a second direction. A first gap region is formed between adjacent first doped layers and second doped layers. A first fine grid is provided on the first doped layer, and a second fine grid is provided on the second doped layer. Both the first fine grid and the second fine grid extend along the first direction, and the second direction intersects with the first direction. A first connector extends along the second direction and is connected to the first fine grid. In a first region of the first surface, a plurality of second insulating blocks corresponding one-to-one with the second fine grid are provided at the intersection of the first connector and the second fine grid. Along the second direction, at least a portion of the second insulating blocks extend into the first gap region adjacent to them.

[0011] In this application, the first connector is connected to the first fine grid, and the current collected by the first fine grid is collected through the first connector and transmitted to the external circuit. In the first region of the first surface, a plurality of second insulating blocks corresponding one-to-one with the second fine grid are provided at the intersection of the first connector and the second fine grid. The second insulating blocks block the first connector and the second fine grid to prevent short circuits in the battery string, thereby improving the reliability of the battery string.

[0012] Furthermore, in this application, at least a portion of the second insulating block extends into the adjacent first spacing region along the second direction. This arrangement ensures that the solidification of the second insulating block does not affect the reliability of the connection between the first connector and the first fine grid, thereby preventing poor soldering of the battery string and contributing to improved photoelectric conversion efficiency.

[0013] Furthermore, the second insulating block can fill the first gap area below the first connector. This arrangement can prevent the bonding material from overflowing into the first gap area and connecting to the second grid during the welding process between the first connector and the first grid, thus preventing a short circuit in the battery string and helping to improve the reliability of the battery string.

[0014] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 shows a top view of the battery string in an embodiment of this application;

[0017] Figure 2 shows a partial structural diagram of the battery string in an embodiment of this application;

[0018] Figure 3 shows an enlarged view of the battery string described in Figure 1 in region A1;

[0019] Figure 4 shows a cross-sectional view of the battery string described in Figure 3 along the C1-C2 direction;

[0020] Figure 5 shows an enlarged view of the battery string in region B1 of Figure 1;

[0021] Figure 6 shows a cross-sectional view of the battery string described in Figure 5 along the D1-D2 direction;

[0022] Figure 7 shows a magnified view of the battery string in region B1 of Figure 1;

[0023] Figure 8 shows a cross-sectional view of the battery string described in Figure 7 along the E1-E2 direction;

[0024] Figure 9 shows an enlarged view of the battery string described in Figure 1 in region A2;

[0025] Figure 10 shows an enlarged view of the battery string described in Figure 1 in region B2;

[0026] Figure 11 shows a magnified view of the battery string in region A2 of Figure 1;

[0027] Figure 12 is a magnified view of the battery string described in Figure 1 in region B2.

[0028] Reference numerals: 10: Solar cell; 11: Substrate; 12: First doped layer; 13: Second doped layer; 14: First region; 15: Second region; 20: First fine grid; 21: Thickened section; 22: Second fine grid; 30: First spacer region; 31: Second spacer region; 40: First bonding block; 50: First connector; 51: Second connector; 60: First insulating block; 61: Second insulating block; 70: First connection portion; 71: End line; X: First direction; Y: Second direction. Specific Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, 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, 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.

[0030] The electronic atomizing device provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0031] Referring to Figure 1, a top view of the battery string in an embodiment of this application is shown; referring to Figure 2, a partial structural schematic diagram of the battery string in an embodiment of this application is shown; referring to Figure 3, an enlarged view of the battery string in Figure 1 in region A1 is shown; referring to Figure 4, a cross-sectional view of the battery string in Figure 3 along the C1-C2 direction is shown; referring to Figure 5, an enlarged view of the battery string in Figure 1 in region B1 is shown; referring to Figure 6, a cross-sectional view of the battery string in Figure 5 along the D1-D2 direction is shown; referring to Figure 7, an enlarged view of the battery string in Figure 1 in region B1 is shown; referring to Figure 8, a cross-sectional view of the battery string in Figure 7 along the E1-E2 direction is shown; referring to Figure 9, an enlarged view of the battery string in Figure 1 in region A2 is shown; referring to Figure 10, an enlarged view of the battery string in Figure 1 in region B2 is shown; referring to Figure 11, an enlarged view of the battery string in Figure 1 in region A2 is shown; referring to Figure 12, an enlarged view of the battery string in Figure 1 in region B2 is shown.

[0032] As shown in Figures 1 to 12, this application discloses a battery string, which includes a battery cell 10. The battery cell 10 includes a substrate 11 and multiple first doped layers 12 and multiple second doped layers 13 forming a first surface of the substrate 11. The first doped layers 12 and the second doped layers 13 both extend along a first direction X and are alternately arranged along a second direction Y. A first spacing region 30 is provided between adjacent first doped layers 12 and second doped layers 13. A first fine grid 20 is provided on the first doped layer 12, and a first fine grid 20 is provided on the second doped layer 13. There is a second fine grid 22, and both the first fine grid 20 and the second fine grid 22 extend along the first direction X, and the second direction Y intersects with the first direction X; a first connector 50 extends along the second direction Y and is connected to the first fine grid 20. In the first region 14 of the first surface, a plurality of second insulating blocks 61 corresponding one-to-one with the second fine grid 22 are provided at the intersection of the first connector 50 and the second fine grid 22; along the second direction Y, at least a portion of the second insulating blocks 61 extend into the first interval region 30 adjacent to them.

[0033] The battery string disclosed in this application includes battery cells 10, and each battery cell 10 includes a substrate 11. The substrate 11 is the core component of the battery cell 10 and can convert solar energy into electrical energy. Furthermore, the battery cell 10 in this application embodiment can be a gridless battery cell, which may only have a first connecting portion 70 at the end or a harpoon-shaped structure (not shown in the figure). The substrate 11 has a first surface and a second surface disposed opposite to each other. The first surface is the back surface facing away from sunlight, also referred to as the back side, and the second surface is the light-receiving surface facing sunlight, also referred to as the front side.

[0034] As shown in Figures 1 to 12, the first surface of the substrate 11 has multiple first doped layers 12 and multiple second doped layers 13. It can be understood that the multiple first doped layers 12 and multiple second doped layers 13 are all disposed on the back side of the substrate 11; that is, the solar cell disclosed in this application is a back-contact solar cell. The first doped layers 12 and the second doped layers 13 both extend along a first direction X and are alternately arranged along a second direction Y. The current generated on the substrate 11 is collected through the first doped layers 12 and the second doped layers 13.

[0035] Along the second direction Y, there is a first spacing region 30 between adjacent first doped layers 12 and second doped layers 13. The first spacing region 30 blocks the first doped layer 12 and the second doped layer 13 to prevent the first doped layer 12 and the second doped layer 13 from conducting, which would cause a short circuit in the solar cell and affect the photoelectric conversion efficiency of the solar cell.

[0036] As shown in Figures 1 to 12, a first fine gate 20 is disposed on the first doped layer 12, and a second fine gate 22 is disposed on the second doped layer 13. Both the first fine gate 20 and the second fine gate 22 extend along a first direction X. It can be understood that the first fine gate 20 is disposed on the first doped layer 12, and the extension direction of the first fine gate 20 is the same as the extension direction of the first doped layer 12; the second fine gate 22 is disposed on the second doped layer 13, and the extension direction of the second fine gate 22 is the same as the extension direction of the second doped layer 13.

[0037] It should be noted that in the embodiments of this application, the first direction X can be either the length direction of the substrate 11 or the width direction of the substrate 11. When the first direction X is the length direction of the substrate 11, the second direction Y is the width direction of the substrate 11. When the first direction X is the width direction of the substrate 11, the second direction Y is the length direction of the substrate 11.

[0038] As shown in Figures 1 to 12, the first connector 50 extends along the second direction Y and is connected to the first fine gate 20 so as to collect the current collected by the first fine gate 20 through the first connector 50 and transmit the collected current to the external circuit.

[0039] It should be noted that the first surface of the substrate 11 has a first region 14 and a second region 15. Along the second direction Y, the second region 15 and the first region 14 are spaced apart, and the second region 15 is closer to the side of the substrate 11 than the first region 14.

[0040] In the first region 14 of the first surface of the substrate 11, a plurality of second insulating blocks 61 corresponding one-to-one with the second fine grid 22 are provided at the intersection of the first connector 50 and the second fine grid 22. Each second insulating block 61 blocks the electrical connection between the corresponding second fine grid 22 and the first connector 50, thereby avoiding short circuits in the battery string, affecting the photoelectric conversion efficiency of the battery string, and improving the reliability of the battery string.

[0041] As shown in Figures 1 to 12, at least a portion of the second insulating block 61 extends into the adjacent first spacing region 30 along the second direction Y. It can be understood that a portion of the second insulating block 61 extends into the adjacent first spacing region 30 along the second direction Y. In some embodiments, all of the second insulating blocks 61 extend into the adjacent first spacing region 30.

[0042] In this embodiment, at least a portion of the second insulating block 61 extends into the adjacent first spacing region 30 along the second direction Y. This ensures that after the second insulating block 61 is cured, it does not affect the reliability of the connection between the first connector 50 and the first fine grid 20, thus preventing poor soldering of the battery string and helping to improve the photoelectric conversion efficiency of the battery string.

[0043] Furthermore, the above-mentioned arrangement can also prevent the bonding material from overflowing into the first spacing area 30 and connecting to the second fine grid 22 during the welding process between the first connector 50 and the first fine grid 20, thus avoiding a short circuit in the battery string and helping to improve the reliability of the battery string.

[0044] In this embodiment, the first connector 50 can be a solder strip. Exemplarily, the first connector 50 can be a square solder strip, a circular solder strip, a triangular solder strip, or other polygonal solder strip. Of course, the first connector 50 can also be other connectors. In this embodiment, no particular restrictions are placed on the specific type of the first connector 50. In practical applications, those skilled in the art can select a suitable first connector 50 as needed.

[0045] In some embodiments, as shown in Figures 3 and 4, along the second direction Y, the second insulating block 61 does not extend to the boundary between the adjacent first doped layer 12 and the first spacer region 30.

[0046] As shown in Figures 3 and 4, along the second direction Y, the second insulating block 61 does not extend to the boundary between the adjacent first doped layer 12 and the first spacer region 30. That is, along the second direction Y, the second insulating block 61 extends into the adjacent first spacer region 30, but does not extend to the boundary between the adjacent first spacer region 30 and the adjacent first doped layer 12.

[0047] By implementing the above settings, the reliability of the connection between the first connector 50 and the first fine grid 20 can be avoided after the second insulating block 61 has solidified, and problems such as poor soldering of the battery string can be avoided, thereby helping to improve the reliability of the battery string and improve the photoelectric conversion efficiency of the battery string.

[0048] In some embodiments, as shown in Figures 3 and 4, along the second direction Y, the width of the second insulating block 61 is W1, the width of the second doped layer 13 is W2, and the width of the first spacer region 30 adjacent to the second doped layer 13 is W3, satisfying W2 < W1 ≤ W2 + 2 * W3.

[0049] As shown in Figures 3 and 4, in this embodiment of the application, along the second direction Y, the width of the second insulating block 61 is set to W1, the width of the second doped layer 13 is set to W2, and the width of the first spacer region 30 adjacent to the second doped layer 13 is W3. Specifically, the width W1 of the second insulating block 61 is greater than the width W2 of the second doped layer 13, and the width W1 of the second insulating block 61 is less than or equal to the sum of the width W2 of the second doped layer 13 and twice the width W3 of the first spacer region 30. This configuration allows the second insulating block 61 to cover the side edge of the second doped layer 13 near the first spacer region 30, while simultaneously preventing the second insulating block 61 from extending onto the first doped layer 12 and covering the first fine gate 20, thus preventing the first connector 50 from being electrically connected to the first fine gate 20.

[0050] In this embodiment, by setting the width of the second insulating block 61 to be greater than the width of the second doped layer 13, the second insulating block 61 is sufficient to cover the second doped layer 13, so that the electrical connection between the second fine grid 22 and the first connector 50 is blocked by the second doped layer 13, thereby avoiding short circuits in the battery string, affecting the photoelectric conversion efficiency of the battery string, and improving the reliability of the battery string.

[0051] In this embodiment, the width of the second insulating block 61 is set to be less than or equal to the sum of the width of the second doped layer 13 and twice the width of the first spacing region 30. This prevents the second insulating block 61 from extending onto the adjacent first doped layer 12. After the second insulating block 61 is cured, it will not affect the reliability of the connection between the first connector 50 and the first fine grid 20, thereby avoiding the occurrence of poor soldering in the battery string and helping to improve the photoelectric conversion efficiency of the battery string.

[0052] Furthermore, the second insulating block 61 can cover the side of the second doped layer 13. Even if the bonding material between the first doped layer 12 and the first connector 50 flows into the first spacer region 30, the second insulating block 61 can block the bonding material from being electrically connected to the second fine grid 22, thereby preventing leakage problems in the battery string.

[0053] In some embodiments, as shown in Figures 3 and 4, the battery string disclosed in this application embodiment further includes a plurality of first bonding blocks 40, wherein each first bonding block 40 is disposed at the connection between a first fine grid 20 and a first connector 50; along the thickness direction of the battery cell 10, the height of the first bonding block 40 is greater than the height of the second insulating block 61.

[0054] As shown in Figures 3 and 4, in this embodiment of the application, a first bonding block 40 is provided at the connection between each first fine grid 20 and the first connector 50, so as to improve the reliability of the connection between the first fine grid 20 and the first connector 50, and avoid the occurrence of poor soldering between the first fine grid 20 and the first connector 50, which would affect the photoelectric conversion efficiency of the battery string.

[0055] In this embodiment, along the thickness direction of the battery cell 10, the height of the first bonding block 40 is set to be greater than the height of the second insulating block 61, so as to avoid the second insulating block 61 being too high and supporting the first connector 50. This would prevent the first bonding block 40 adjacent to the second insulating block 61 from contacting the first connector 50, affecting the reliability of the connection between the first bonding block 40 adjacent to the second insulating block 61 and the first connector 50, resulting in poor soldering of the battery string and affecting the photoelectric conversion efficiency of the battery string.

[0056] It should be noted that the first bonding block 40 can be formed by screen printing metal paste onto the connection between the first fine gate 20 and the first connector 50. For example, tin paste can be screen printed onto the connection between the first fine gate 20 and the first connector 50. In some embodiments, the first bonding block can also be formed by accumulating a solderable coating (e.g., a solder layer) on the first connector 50 at the location requiring soldering, such as on the thickened section.

[0057] In some embodiments, as shown in Figures 3 and 4, the first fine grid 20 further includes a thickened section 21 along the second direction Y, the width of the thickened section 21 being greater than the width of other portions of the first fine grid 20, and the first connecting block 40 being disposed between the thickened section 21 and the first connector 50.

[0058] As shown in Figures 3 and 4, the first fine grid 20 is provided with a thickened section 21. Along the second direction Y, the width of the thickened section 21 is greater than the width of other parts of the first fine grid 20. The first connecting block 40 is located between the thickened section 21 of the first fine grid 20 and the first connector 50. That is, the thickened section 21 connects the first fine grid 20 to the first connecting block 40 and the first connector 50. This further improves the reliability of the connection between the first fine grid 20 and the first connector 50, ensuring that the first fine grid 20 is connected to the first connector 50. The first connector 50 can transmit the current collected by the first fine grid 20 to the external circuit, improving the photoelectric conversion efficiency of the battery string and avoiding poor soldering between the first fine grid 20 and the first connector 50, which would affect the photoelectric conversion efficiency of the battery string.

[0059] It is understood that the first fine gate 20 in this embodiment includes a first fine gate body and a thickened section 21 connected to the first fine gate body. The first fine gate body can burn through the passivation layer on the surface of the substrate 11 and is connected to the substrate 11 to collect the current generated by the substrate 11. The thickened section 21 cannot burn through the passivation layer on the surface of the substrate 11, and can only collect the current collected by the first fine gate body and transmit the collected current to the first connector 50. The thickened section 21 can be integrally formed with the first fine gate body (e.g., by printing) or formed in two separate steps (e.g., printing the thickened section 21 first, and then printing the first fine gate body, with overlapping parts).

[0060] In some embodiments, as shown in Figures 5 and 6, the battery string disclosed in this application further includes a second connector 51. The second connector 51 extends along a second direction Y and along a first direction X. The second connector 51 is spaced apart from the first connector 50. The second connector 51 is connected to the second fine grid 22. At the intersection of the second connector 51 and the first fine grid 20, a plurality of first insulating blocks 60 corresponding one-to-one with the first fine grid 20 are provided. Along the second direction Y, at least a portion of the first insulating blocks 60 extend into the first spacing region 30 adjacent to them.

[0061] As shown in Figures 5 and 6, the battery string in this embodiment further includes a second connector 51. The second connector 51 extends along the second direction Y and is spaced apart from the first connector 50 along the first direction X. The second connector 51 is connected to the second fine grid 22, and the first connector 50 is connected to the first fine grid 20. When the first fine grid 20 is a positive fine grid, the second fine grid 22 is a negative fine grid. When the first fine grid 20 is a negative fine grid, the second fine grid 22 is a positive fine grid. By connecting the first connector 50 to the first fine grid 20 and the second connector 51 to the second fine grid 22, the positive and negative currents generated by the battery cell 10 are collected and transmitted, respectively.

[0062] As shown in Figures 5 and 6, in this embodiment of the application, a plurality of first insulating blocks 60 corresponding one-to-one with the first fine grid 20 are provided at the intersection of the second connector 51 and the first fine grid 20, so as to block the first fine grid 20 and the second connector 51 through the first insulating blocks 60, thereby preventing the first fine grid 20 and the second connector 51 from conducting, which would cause the battery string to short-circuit and affect the photoelectric conversion efficiency of the photovoltaic module.

[0063] It should be noted that, as shown in Figures 5 and 6, in this embodiment of the application, at least a portion of the first insulating block 60 extends into the adjacent first spacing region 30 along the second direction Y. It can be understood that a portion of the first insulating block 60 extends into the adjacent first spacing region 30 along the second direction Y. In some embodiments, all of the first insulating block 60 may extend into the adjacent first spacing region 30.

[0064] In this embodiment, at least a portion of the first insulating block 60 extends into the adjacent first spacing region 30 along the second direction Y. This ensures that the solidification of the first insulating block 60 does not affect the reliability of the connection between the second connector 51 and the second fine grid 22, thereby preventing poor soldering of the battery string and helping to improve the photoelectric conversion efficiency of the battery string.

[0065] Furthermore, the above-mentioned arrangement can also prevent the bonding material from overflowing into the first spacing area 30 and connecting to the first fine grid 20 during the welding process between the second connector 51 and the second fine grid 22, thus avoiding a short circuit in the battery string and helping to improve the reliability of the battery string.

[0066] It should be noted that the second connector 51 in this embodiment can be a solder strip. Exemplarily, the second connector 51 can be a square solder strip, a circular solder strip, a triangular solder strip, or other polygonal solder strip. Of course, the second connector 51 can also be other connectors. In this embodiment, no particular restrictions are placed on the specific type of the second connector 51. In practical applications, those skilled in the art can select a suitable second connector 51 as needed.

[0067] In some embodiments, as shown in Figures 5 and 6, in this embodiment of the application, the width of the first doped layer 12 along the second direction Y is equal to the width of the second doped layer 13.

[0068] As shown in Figures 5 and 6, in this embodiment of the application, the width of the first doped layer 12 is set to be equal to the width of the second doped layer 13 along the second direction Y, so as to facilitate the fabrication of the solar cell.

[0069] Of course, the above-described method of setting the width of the first doped layer 12 along the second direction Y to be equal to the width of the second doped layer 13 is merely one specific implementation of this application and is not intended to limit this application. In practical applications, those skilled in the art can also set the width of the first doped layer 12 and the width of the second doped layer 13 as needed.

[0070] In some embodiments, as shown in Figures 7 and 8, the battery string in this embodiment further includes a second connector 51. The second connector 51 extends along the second direction Y and is spaced apart from the first connector 50 along the first direction X. The second connector 51 is connected to the second fine grid 22. At the intersection of the second connector 51 and the first fine grid 20, a plurality of first insulating blocks 60 corresponding one-to-one with the first fine grid 20 are provided. Along the second direction Y, the width of the first insulating block 60 is smaller than the width of the first doped layer 12 corresponding to it. On the plane where the battery cell 10 is located, the first insulating block 60 has a second projection, which falls into the first doped layer 12 corresponding to it.

[0071] As shown in Figures 7 and 8, the battery string in this embodiment further includes a second connector 51. The second connector 51 extends along a second direction Y and is spaced apart from the first connector 50 along a first direction X. The second connector 51 is connected to the second fine grid 22, and the first connector 50 is connected to the first fine grid 20. When the first fine grid 20 is a positive fine grid, the second fine grid 22 is a negative fine grid. When the first fine grid 20 is a negative fine grid, the second fine grid 22 is a positive fine grid. By connecting the first connector 50 to the first fine grid 20 and the second connector 51 to the second fine grid 22, the positive and negative currents generated by the battery cell 10 are collected and transmitted.

[0072] As shown in Figures 7 and 8, in this embodiment of the application, a plurality of first insulating blocks 60 corresponding one-to-one with the first fine grid 20 are provided at the intersection of the second connector 51 and the first fine grid 20, so as to block the first fine grid 20 and the second connector 51 through the first insulating blocks 60, thereby preventing the first fine grid 20 and the second connector 51 from conducting, which would cause the battery string to short-circuit and affect the photoelectric conversion efficiency of the photovoltaic module.

[0073] It should be noted that, as shown in Figures 7 and 8, in this embodiment of the application, along the second direction Y, the width of the first insulating block 60 is smaller than the width of its corresponding first doped layer 12, and on the plane where the battery cell 10 is located, the first insulating block 60 has a second projection, which falls into its corresponding first doped layer 12. Through the above arrangement, the first insulating block 60 can block the first fine grid 20 from the second connector 51, preventing the first fine grid 20 from conducting with the second connector 51, thus avoiding a short circuit in the battery string and affecting the photoelectric conversion efficiency of the battery string.

[0074] Furthermore, through the above-mentioned arrangement, the first insulating block 60, after being cured, will not extend between the second connector 51 and the second fine grid 22, thus affecting the reliability of the connection between the second connector 51 and the second fine grid 22, thereby avoiding the occurrence of poor soldering in the battery string and helping to improve the photoelectric conversion efficiency of the battery string.

[0075] In some embodiments, as shown in Figures 7 and 8, along the second direction Y, the width of the first doped layer 12 is greater than the width of the second doped layer 13, and the doping type of the second doped layer 13 is the same as the doping type of the substrate 11.

[0076] As shown in Figures 7 and 8, in some embodiments, specifically those of this application, the width of the first doped layer 12 is set to be greater than the width of the second doped layer 13 along the second direction Y, and the doping type of the second doped layer 13 is set to be the same as the doping type of the substrate 11, while the doping type of the first doped layer 12 is different from that of the substrate 11. In this case, the first doped layer 12 can form a PN junction with the substrate 11, and setting the width of the first doped layer 12 to be greater than the width of the second doped layer 13 helps to improve the photoelectric conversion efficiency of the battery string.

[0077] Furthermore, since the first doped layer 12 is used to collect holes, the probability of leakage from the side of the first doped layer 12 is very small. In this embodiment, along the second direction Y, the width of the first insulating block 60 is set to be smaller than the width of the corresponding first doped layer 12, and on the plane where the battery cell 10 is located, the first insulating block 60 has a second projection, which is set to fall within the corresponding first doped layer 12. The above settings will not cause leakage from the first doped layer 12, and can also reduce the material usage of the first insulating block 60, thereby helping to reduce the production cost of the battery string. Of course, due to printing accuracy issues, there may be a small number of first insulating blocks 60 whose second projection on the battery cell 10 is offset from the boundary of the first doped layer 12 on one side. In some embodiments, along the second direction Y, the width of the first insulating block 60 is approximately the same as the width of the second insulating block 61. Alternatively, in other embodiments, along the second direction Y, the width of the first insulating block 60 is approximately the same as the width of the second insulating block 61, for example, the width of the insulating block covering the P-type fine grid is greater than the width of the insulating block covering the N-type fine grid.

[0078] In some embodiments, as shown in Figures 9 to 12, in this embodiment, the first surface of the substrate 11 further includes a second region 15 disposed adjacent to the first region 14 along the second direction Y. A first connecting portion 70 is disposed on the second region 15, and the first connecting portion 70 extends along the second direction Y. Along the second direction Y, the second region 15 is closer to the edge of the substrate 11 than the first region 14. The first connecting portion 70 is connected to multiple first doped layers 12. Along the first direction X, there is a second spacing region 31 between the second doped layer 13 and the first connecting portion 70, and the second spacing region 31 is connected to the first spacing region 30. The second doped layers 13 on both sides of the first connecting portion 70 have second fine gates 22. A second insulating block 61 is disposed at the end of the second fine gate 22 near the first connecting portion 70, and the second insulating block 61 extends into the first spacing region 30 adjacent to it and into the second spacing region 31 adjacent to it.

[0079] As shown in Figures 9 to 12, the first surface of the substrate 11 has a first region 14 and a second region 15, which are arranged sequentially along the second direction Y, and the second region 15 is closer to the edge of the substrate 11 than the first region 14.

[0080] The second region 15 is provided with a first connection portion 70, which extends along the second direction Y and is connected to multiple first doped layers 12. The first connection portion 70 is connected to the first fine gate 20 located on the first doped layer 12, so that the current collected by the first fine gate 20 is collected through the first connection portion 70 and the collected current is transmitted to the first connector 50. The collected current is transmitted to the external circuit through the first connector 50.

[0081] As shown in Figures 9 to 12, along the first direction X, a second spacing region 31 exists between the second doped layer 13 and the first connecting portion 70, and the second spacing region 31 is connected to the first spacing region 30. That is, along the second direction Y, a first spacing region 30 exists between adjacent first doped layers 12 and second doped layers 13 to block the first doped layer 12 and the second doped layer 13 from conducting, thus preventing a short circuit in the solar cell and affecting its photoelectric conversion efficiency. Similarly, along the first direction X, a second spacing region 31 exists between the second doped layer 13 and the adjacent first connecting portion 70 to block the second doped layer 13 and the adjacent first connecting portion 70 from conducting, thus preventing a short circuit in the solar cell and affecting its photoelectric conversion efficiency.

[0082] As shown in Figures 9 to 12, along the first direction X, the second doped layers 13 on both sides of the first connecting portion 70 have second fine gates 22. A second insulating block 61 is provided at the end of the second fine gate 22 near the first connecting portion 70. The second insulating block 61 extends into the adjacent first spacing region 30 and the adjacent second spacing region 31. The second insulating block 61 blocks the second fine gate 22 from the first connecting member 50 and the first connecting portion 70, preventing the second fine gate 22 from conducting with the first connecting member 50 or the first connecting portion 70, which would cause a short circuit in the solar cell 10, affecting the reliability of the solar cell 10 and thus the photoelectric conversion efficiency of the solar cell string.

[0083] In some embodiments, as shown in Figures 9 to 12, the first connecting portion 70 in this embodiment is provided with an end line 71, which extends along the second direction Y and is connected to the first fine grid 20; along the first direction X, there is a first distance d1 between the end of the second fine grid 22 near the end line 71 and the end of the corresponding second insulating block 61 near the end line 71, which satisfies 0.3mm≤d1≤1.5mm.

[0084] As shown in Figures 9 and 12, the first connection portion 70 includes a first connection portion body and an end line 71 connected to the first connection portion body. The end line 71 extends along the second direction Y, and along the second direction Y, the end line 71 is closer to the edge of the substrate 11 than the first connection portion body. The end line 71 is connected to the first fine gate 20 to collect the current gathered by the first fine gate 20, and transmits the collected current to an external circuit through the first connector 50.

[0085] It should be noted that, in this embodiment of the application, along the first direction X, there is a first distance d1 between the end of the second fine grid 22 near the end line 71 and the end of the corresponding second insulating block 61 near the end line 71. This first distance is greater than or equal to 0.3 mm and less than or equal to 1.5 mm. For example, this first distance can be 0.3 mm, 0.5 mm, 0.7 mm, 1.0 mm, 1.2 mm, or 1.5 mm.

[0086] In this embodiment, along the first direction X, the first distance between the end of the second fine grid 22 near the end line 71 and the corresponding end of the second insulating block 61 near the end line 71 is set to be greater than or equal to 0.3 mm and less than or equal to 1.5 mm. This allows the second insulating block 61 to cover the end of the second fine grid 22 near the end line 71, preventing the end of the second fine grid 22 near the end line 71 from connecting to the first connector 50, which could cause a short circuit in the battery string and affect the photoelectric conversion efficiency of the battery string.

[0087] It should be noted that the terminal line 71 in this embodiment will not burn through the passivation layer on the surface of the substrate 11, that is, the terminal line 71 cannot collect the current generated by the substrate 11. The terminal line 71 is connected to the first fine gate 20, which can collect the current collected by the first fine gate 20 and transmit it to the external circuit through the first connector 50.

[0088] Additionally, the first connector 50 extends along the second direction Y. The first connector 50 can extend from above the second region 15 to above the first region 14. The first connector 50 covers the end line 71 on the second region 15 and covers the thickened section 21 on the first region 14, so that the first connector 50 can collect the current collected by the end line 71 and the thickened section 21 and transmit it to the external circuit.

[0089] In some embodiments, as shown in Figures 9 to 12, the second fine gate 22 and the first doped layer 12 or the first connection portion 70 in this application embodiment have a second distance d2, which satisfies 0.1mm≤d2≤0.5mm; and / or, satisfies d1>d2.

[0090] As shown in Figures 9 to 12, in this embodiment of the application, there is a second distance between the second fine gate 22 and the first doped layer 12 or the first connecting portion 70. This second distance is greater than or equal to 0.1 mm and less than or equal to 0.5 mm, so as to avoid the second fine gate 22 from being connected to the first doped layer 12 or the first connecting portion 70, which would cause a short circuit in the battery string, thereby improving the reliability of the battery string and improving the photoelectric conversion efficiency of the battery string.

[0091] For example, the second distance between the second fine gate 22 and the first doped layer 12 or the first connection portion 70 can be set to 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, etc.

[0092] It should be noted that, in this embodiment, the second distance d2 between the second fine gate 22 and the first doped layer 12 or the first connecting portion 70 can also be set to be greater than the first distance d1 between the end of the second fine gate 22 near the end line 71 and the end of the corresponding second insulating block 61 near the end line 71, so that the second insulating block 61 at least partially extends into the first spacer region 30 or the second spacer region 31. This ensures that after the second insulating block 61 is cured, it will not affect the reliability of the connection between the first connecting member 50 and the first fine gate 20, thereby avoiding poor soldering of the battery string and helping to improve the photoelectric conversion efficiency of the battery string.

[0093] Furthermore, the above-mentioned arrangement can also prevent the bonding material from overflowing into the first spacing area 30 and connecting to the second fine grid 22 during the welding process between the first connector 50 and the first fine grid 20, thus avoiding a short circuit in the battery string and helping to improve the reliability of the battery string.

[0094] Furthermore, the second insulating block 61 can cover the side of the second doped layer 13, so that even if the bonding material between the first doped layer 12 and the first connector 50 flows into the first spacer region 30, the second insulating block 61 can prevent the bonding material from being electrically connected to the second fine grid 22, thereby preventing leakage problems in the battery string.

[0095] In some embodiments, as shown in Figures 9 to 12, the second insulating block 61 in this application embodiment extends to the first connecting portion 70 and / or the first doped layer 12.

[0096] As shown in Figures 9 to 12, in this embodiment of the application, the second insulating block 61 extends to the first connecting portion 70 and / or the first doped layer 12, so that the second insulating block 61 can completely fill the first spacing region 30 and / or the second spacing region 31, thereby ensuring that the second fine grid 22 and the first connecting member 50 are blocked, avoiding short circuits in the battery string, and improving the photoelectric conversion efficiency of the battery string.

[0097] Furthermore, the above-mentioned arrangement can also prevent the bonding material between the first connector 50 and the first fine grid 20 from overlapping onto the second fine grid 22, causing the first fine grid 20 and the second fine grid 22 to conduct, resulting in a short circuit in the battery string and thus affecting the photoelectric conversion efficiency of the battery string.

[0098] In some embodiments, as shown in Figures 11 and 12, the second insulating block 61 in this embodiment covers the end of the second fine grid 22 on one side of the first connecting portion 70 and extends through the first connecting portion 70 to cover the end of the second fine grid 22 on the other side of the first connecting portion 70.

[0099] As shown in Figures 11 and 12, in this embodiment, the second insulating block 61 is elongated and extends along the second direction Y. One end of the second insulating block 61 covers the end of the second fine grid 22 on one side of the first connecting portion 70, and the second insulating block 61 extends through the first connecting portion 70 and covers the end of the second fine grid 22 on the other side of the first connecting portion 70. Thus, one second insulating block 61 can cover the ends of the two second fine grids 22 located on both sides of the first connecting portion 70, facilitating the fabrication of the battery string, simplifying the battery string fabrication process, and reducing the battery string fabrication cost.

[0100] It should be noted that, in this embodiment, both the first doped layer 12 and the second doped layer 13 are polycrystalline silicon materials, the solar cell is a TBC cell, and a tunneling oxide layer (not shown in the figure) is also present between the first doped layer 12 and the second doped layer 13 and the substrate 11. The first spacer region 30 is the portion between the first doped layer 12 and the second doped layer 13 without a doped layer. The edge of the first spacer region 30 is defined by the first doped layer 12 and the second doped layer 13, thus requiring an insulating block for electrical isolation of the first spacer region 30. Furthermore, a passivation insulating layer is present between the first doped layer 12 and the first fine gate 20, and between the second doped layer 13 and the second fine gate 22. The first fine gate 20 and the second fine gate 22 at least partially burn through the passivation insulating layer to electrically connect with the first doped layer 12 and the second doped layer 13, and the passivation insulating layer covers the first spacer region 30. Further, the insulating block at least covers a portion of the passivation insulating layer within the first spacer region 30.

[0101] Of course, the above-described configuration of the first doped layer 12 and the second doped layer 13 is only a few embodiments of this application and is not intended to limit the scope of this application. In practical applications, those skilled in the art can also configure the specific types of the first doped layer 12 and the second doped layer 13 as needed.

[0102] This application also discloses a photovoltaic module, which includes the battery string described in the above embodiments.

[0103] It should be noted that the photovoltaic modules disclosed in this application have the same structure as the battery strings described in the above embodiments, and their beneficial effects are also similar. Further details will not be repeated here.

[0104] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0105] The terms "an embodiment," "embodiment," or "one or more embodiments" as used herein mean that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of this application. Furthermore, please note that the examples of the phrase "in one embodiment" do not necessarily all refer to the same embodiment.

[0106] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of this application may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0107] In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. This application can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In a unit claim enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

[0108] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A battery string, wherein, include: A solar cell includes a substrate and multiple first doped layers and multiple second doped layers forming a first surface of the substrate. The first doped layers and the second doped layers both extend along a first direction and are alternately arranged along a second direction. There is a first gap between adjacent first doped layers and second doped layers. A first fine grid is provided on the first doped layer and a second fine grid is provided on the second doped layer. The first fine grid and the second fine grid both extend along the first direction, and the second direction intersects with the first direction. A first connector extends along the second direction and is connected to the first fine grid. In a first region of the first surface, a plurality of second insulating blocks corresponding one-to-one with the second fine grid are provided at the intersection of the first connector and the second fine grid. Along the second direction, at least a portion of the second insulating blocks extend into the first interval region adjacent to them.

2. The battery string according to claim 1, wherein, Along the second direction, the second insulating block does not extend to the boundary between the first doped layer and the first spacer region adjacent to it.

3. The battery string according to claim 1, wherein, Along the second direction, the width of the second insulating block is W1, the width of the second doped layer is W2, and the width of the first spacer region adjacent to the second doped layer is W3, satisfying W2<W1≤W2+2*W3.

4. The battery string according to any one of claims 1-3, wherein, The battery string also includes multiple first bonding blocks. Each of the first connecting blocks is disposed at the connection point between the first fine grid and the first connector; Along the thickness direction of the battery cell, the height of the first bonding block is greater than the height of the second insulating block.

5. The battery string according to claim 4, wherein, The first fine grid includes a thickened section, and along the second direction, the width of the thickened section is greater than the width of the other portions of the first fine grid. The first connecting block is disposed between the thickened section and the first connector.

6. The battery string according to claim 1, wherein, The battery string also includes: The second connector extends along the second direction and is spaced apart from the first connector along the first direction; the second connector is connected to the second fine grid. At the intersection of the second connector and the first fine grid, a plurality of first insulating blocks corresponding one-to-one with the first fine grid are provided; along the second direction, at least a portion of the first insulating blocks extend into the first interval region adjacent to them.

7. The battery string according to claim 6, wherein, Along the second direction, the width of the first doped layer is equal to the width of the second doped layer.

8. The battery string according to claim 1, wherein, The battery string also includes: The second connector extends along the second direction and is spaced apart from the first connector along the first direction; the second connector is connected to the second fine grid. At the intersection of the second connector and the first fine gate, a plurality of first insulating blocks corresponding one-to-one with the first fine gate are provided. Along the second direction, the width of the first insulating block is smaller than the width of the first doped layer corresponding to it. On the plane where the battery cell is located, the first insulating block has a second projection, which falls into the first doped layer corresponding to it.

9. The battery string according to claim 8, wherein, Along the second direction, the width of the first doped layer is greater than the width of the second doped layer, and the doping type of the second doped layer is the same as the doping type of the substrate.

10. The battery string according to claim 1, wherein, The first surface further includes a second region disposed adjacent to the first region along the second direction, and a first connecting portion is disposed on the second region, the first connecting portion extending along the second direction; along the second direction, the second region is closer to the edge of the substrate than the first region; The first connecting portion is connected to multiple first doped layers. Along the first direction, there is a second spacing region between the second doped layer and the first connecting portion. The second spacing region is connected to the first spacing region. The second doped layer on both sides of the first connection portion has a second fine gate; a second insulating block is provided at the end of the second fine gate near the first connection portion, and the second insulating block extends into the first spacer region adjacent to it and the second spacer region adjacent to it.

11. The battery string according to claim 10, wherein, An end line is provided on the first connecting portion, the end line extends along the second direction, and the end line is connected to the first fine grid; Along the first direction, there is a first distance d1 between the end of the second fine grid near the end line and the end of the corresponding second insulating block near the end line, satisfying 0.3mm≤d1≤1.5mm.

12. The battery string according to claim 11, wherein, The second fine gate has a second distance d2 between it and the first doped layer or the end line, which satisfies 0.1mm≤d2≤0.5mm.

13. The battery string according to claim 12, wherein, The condition d1 > d2 is satisfied.

14. The battery string according to claim 10, wherein, The second insulating block extends onto the first connecting portion.

15. The battery string according to claim 10, wherein, The second insulating block extends onto the first doped layer.

16. The battery string according to claim 10, wherein, The second insulating block covers the end of the second fine grid on one side of the first connecting portion and extends through the first connecting portion to cover the end of the second fine grid on the other side of the first connecting portion.

17. A photovoltaic module, wherein, Includes the battery string according to any one of claims 1-16.

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