Back contact cell and solar cell module

Abstract

The utility model relates to the field of solar photovoltaic technology, and in particular to a back-contact cell and a solar cell assembly. The back-contact cell comprises a cell body, an insulating glue and a grid line, and the back of the cell body is provided with an insulating glue and a grid line; in the direction away from the cell body, the height of the insulating glue is greater than the height of the grid line, and the Mohs hardness range of the end of the insulating glue away from the back-contact cell is 2-7. In the direction away from the cell body, the height of the insulating glue is greater than the height of the grid line, and when the back-contact cell stacks a plurality of back-contact cells during the transfer process, the insulating glue contacts the front of the adjacent cell body, because the insulating glue is softer than the front of the cell body, and the end of the insulating glue with a Mohs hardness of 2-7 will not scratch the front of the cell body; moreover, the grid line will not protrude from the insulating glue and scratch the front of the adjacent cell body; effectively reducing the possibility of front damage to the back-contact cell during the transfer process.

Description

Technical Field

[0001] The utility model relates to the technical field of solar photovoltaics, in particular to a back contact cell sheet and a solar cell assembly. Background Art

[0002] BC type cells (back contact cells) have the P region, N region and gate lines located on the back of the solar cell. The front of the cell uses silicon nitride or silicon oxide as a passivation layer. There is no metal electrode to block it, which maximizes the use of incident light, reduces optical losses, and brings more effective power generation area. Back contact cells have high conversion efficiency and are more beautiful in appearance.

[0003] After the back contact cell is prepared, it needs to be transported, for example, the back contact cell is transported to the laminating equipment for the preparation of the battery assembly. When the back contact cell is transported, multiple back contact cells need to be stacked. In order to avoid scratches between the back contact cells during transportation, especially scratches on the front of the back contact cell, when the back contact cell is stacked, isolation paper is used to block the adjacent back contact cells.

[0004] However, the release paper is relatively thin and light, and is easy to move when used, resulting in poor isolation effect. Utility Model Content

[0005] In view of this, the utility model proposes a back-contact cell and a solar cell module, aiming to partially or completely solve the technical problems that the existing back-contact cell uses isolation paper for isolation, the isolation paper is relatively thin, the isolation paper is easy to move during use, and the isolation effect is poor.

[0006] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0007] In a first aspect, an embodiment of the utility model provides a back-contact battery cell, which includes a battery cell body, an insulating glue and a grid line, wherein the insulating glue and the grid line are provided on the back side of the battery cell body; in a direction away from the battery cell body, the height of the insulating glue is greater than the height of the grid line, and the Mohs hardness range of the end of the insulating glue away from the back-contact battery cell is 2-7.

[0008] Optionally, the insulating glue comprises a first insulating glue and a second insulating glue; the first insulating glue is connected to the back side of the back contact cell and covers at least a portion of the gate line; the second insulating glue

[0009] The insulating adhesive covers at least a portion of the surface of the first insulating adhesive.

[0010] Optionally, the insulating glue includes a first insulating glue and a second insulating glue; the first insulating glue is connected to the back side of the back contact battery cell and covers at least part of the gate line; the second insulating glue is in a convex structure, and the second insulating glue is connected to at least part of the surface of the first insulating glue away from the battery cell body.

[0011] Optionally, the Mohs hardness range of the second insulating adhesive is 2-7.

[0012] Optionally, the insulating glue only includes a first insulating glue, and the first insulating glue is connected to the back side of the back contact cell and covers at least a portion of the gate line.

[0013] Optionally, in a direction away from the battery cell body, the insulating glue has at least two heights, and the height of the insulating glue close to the edge of the battery cell body is greater than or equal to the height of the insulating glue located in the rest of the battery cell body.

[0014] Optionally, in a direction away from the battery cell body, the height of the insulating glue ranges from 15um to 50um.

[0015] Optionally, the thickness of the second insulating adhesive is in the range of 5um-10um.

[0016] Optionally, the end of the insulating glue away from the back contact battery sheet is UV glue.

[0017] In a second aspect, an embodiment of the utility model further provides a solar cell assembly, wherein the solar cell assembly comprises the above-mentioned back contact cell sheet.

[0018] The utility model discloses a back-contact cell. In the direction away from the cell body, the height of the insulating glue is greater than the height of the grid line. When the back-contact cell stacks a plurality of back-contact cells during the transfer process, the insulating glue contacts the front of the adjacent cell body. Since the Mohs hardness of the end of the insulating glue away from the back-contact cell is in the range of 2-7, the insulating glue is softer than the front of the cell body, and the end of the insulating glue with a Mohs hardness of 2-7 will not scratch the front of the cell body; moreover, the grid line will not protrude from the insulating glue and scratch the front of the adjacent cell body. The setting of the insulating glue effectively reduces the possibility of front damage to the back-contact cell during the transfer process. Moreover, by setting the insulating glue on the back of the cell body, it is also possible to avoid the insulating glue from blocking light, thereby ensuring the photoelectric conversion efficiency of the back-contact cell.

[0019] The above description is only an overview of the technical solution of the utility model. In order to more clearly understand the technical means of the utility model, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the utility model more obvious and easy to understand, the following is a specific description of the utility model.

[0020] Implementation method. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for describing the embodiments are briefly introduced below.

[0022] Figure 1 It is a schematic diagram of the partial structure of the back side of the back contact solar cell according to an embodiment of the utility model;

[0023] Figure 2 for Figure 1 A-A is a schematic structural diagram of a cross-sectional view of a first embodiment;

[0024] Figure 3 for Figure 1 A-A is a schematic structural diagram of a cross-sectional view of a second embodiment;

[0025] Figure 4 for Figure 1 A-A is a schematic structural diagram of a cross-sectional view of a third embodiment;

[0026] Figure 5 It is a structural schematic diagram of a partial side view of a back contact battery sheet according to an embodiment of the utility model;

[0027] Figure 6 This is a schematic diagram of the edge position of the back contact battery cell described in an embodiment of the utility model.

[0028] Description of reference numerals:

[0029] 10-battery body;

[0030] 20 - insulating glue; 21 - first insulating glue; 22 - second insulating glue;

[0031] 30 - grid line; 31 - first main grid; 32 - first fine grid; 33 - second fine grid. DETAILED DESCRIPTION

[0032] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can also be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0033] The back contact cell has the P region, N region and gate line 30 all located on the back of the cell, and the front of the cell uses silicon nitride or silicon oxide as a passivation layer. When the back contact cell is transported, multiple back contact cells need to be stacked. After multiple back contact cells are stacked, the front of the back contact cell is easily scratched by the gate line 30 on the back of the adjacent back contact cell.

[0034] Reference Figure 1 , which shows a schematic diagram of the back structure of a back-contact battery cell provided by an embodiment of the utility model, the back-contact battery cell comprises a battery cell body 10, an insulating glue 20 and a gate line 30, the back of the battery cell body 10 is provided with the insulating glue 20 and the gate line 30; in the direction away from the battery cell body 10, the height of the insulating glue 20 is greater than the height of the gate line 30, and the insulating glue 20 is away from the back contact battery cell.

[0035] The Mohs hardness range of the end is 2-7.

[0036] Specifically, the front side of the cell body 10 is the light-receiving side, the back side of the cell body 10 is the backlight side, and the grid lines 30 and the isolation glue are arranged on the back side of the cell body 10 .

[0037] Among them, the insulating glue 20 of the back contact battery cell has a variety of usage structures, and the embodiments of the present application do not specifically limit this. For example, when the gate line 30 includes a fine grid and a main grid, the insulating glue 20 is connected to the fine grid to avoid a short circuit caused by the fine grid. For example, the gate line 30 includes a fine grid but does not include a main grid; the fine grid outputs electrical energy through a welding strip. At this time, the insulating glue 20 can be connected to the welding strip, and the insulating glue 20 is used to fix the welding strip or avoid a short circuit at the welding strip. For example, the gate line 30 includes a fine grid but does not include a main grid. In order to avoid a short circuit caused by the fine grid, an insulating glue 20 is set on the end of the fine grid. For another example, the insulating glue 20 is not connected to the welding strip, the gate line 30, etc., and the insulating glue 20 is only connected to the back of the battery cell body 10. The present application does not specifically limit the setting position of the insulating glue 20, the specific structure of the gate line 30, the setting position of the gate line 30, and whether the insulating glue 20 is connected to the gate line 30. In order to more clearly describe the technical solution of the present application, refer to Figure 1 The embodiment shown is described. Figure 1In the back contact cell, the grid line 30 includes a first main grid 31, a first fine grid 32, and a second fine grid 33. The first main grid 31 and the first fine grid 32 have the same polarity, and the first main grid 31 and the second fine grid 33 have opposite polarities. For example, the first main grid 31 and the first fine grid 32 are positive electrodes, and the second fine grid 33 is negative electrodes. The first main grid 31 and the first fine grid 32 are connected. There is a gap between the first main grid 31 and the second fine grid 33 and they are not connected. The first fine grid 32 and the second fine grid 33 are parallel and spaced apart. In order to avoid short circuits between opposite-sex grid lines, insulating glue 20 is respectively provided at the ends of the first fine grid 32 and the ends of the second fine grid 33. It should be noted that the grid line 30 also includes a second main grid (not shown), and the second main grid has opposite polarity to the first main grid 31.

[0038] In the back contact cell of the embodiment of the present application, the height of the insulating glue 20 is greater than the height of the gate line 30 in the direction away from the cell body 10. When the back contact cell stacks multiple back contact cells during the transfer process, the insulating glue 20 contacts the front of the adjacent cell body 10. Since the Mohs hardness range of the end of the insulating glue 20 away from the back contact cell is 2-7, the end of the insulating glue 20 is not only softer than the front of the cell body 10, but also the end of the insulating glue 20 will not scratch the front of the cell body 10; moreover, the gate line 30 will not protrude from the insulating glue 20 and scratch the front of the adjacent cell body 10. The setting of the insulating glue 20 effectively reduces the possibility of front damage to the back contact cell during the transfer process. Moreover, the setting of the insulating glue 20 on the back of the cell body 10 can also avoid the insulating glue 20 from blocking the light, thereby ensuring the photoelectric conversion efficiency of the back contact cell. It should be noted that it is not the case that the Mohs hardness of the end of the insulating glue 20 away from the back contact cell is less than the Mohs hardness of the front of the cell body 10 that can achieve that the end of the insulating glue 20 away from the back contact cell will not scratch the front of the adjacent cell body 10, but the Mohs hardness of the end of the insulating glue 20 away from the back contact cell needs to be in the range of 2-7 to achieve that the front of the adjacent cell body 10 will not be scratched. Among them, the front of the cell body 10 generally uses silicon nitride as a passivation layer, and the Mohs hardness of silicon nitride is in the range of 9-9.5. When the Mohs hardness of the end of the insulating glue 20 away from the back contact cell is in the range of 2-7, the hardness difference between the Mohs hardness of the end and the Mohs hardness of the front of the cell body 10 can achieve that the end of the insulating glue 20 will not scratch the front of the cell body 10.

[0039] Further, optionally, the gate line 30 has multiple types (for example Figure 1 In the direction away from the battery cell body 10 , the height of the insulating glue 20 is greater than the height of all the grid lines 30 .

[0040] Furthermore, when stacking multiple back-contact battery cells in the embodiment of the present application during the transfer process, there is no need to set isolation paper between two adjacent back-contact battery cells, which can reduce the waste caused by isolation paper; and the technical problem that the isolation paper is relatively thin and easy to move during use, resulting in poor isolation effect.

[0041] Further, see Figures 2 to 4 As shown, the direction away from the battery cell body 10 is shown by the arrow Z.

[0042] Optionally, the embodiment of the present application does not specifically limit the manner in which the insulating glue 20 is disposed on the battery cell body 10. For example, the insulating glue 20 is printed on the back of the battery cell body 10; for example, the insulating glue 20 is disposed on the back of the battery cell body 10 by dispensing; for another example, the insulating glue 20 is disposed on the back of the battery cell body 10 by inkjet.

[0043] Optionally, in order to more clearly describe the technical solution of this application, Figure 2 Shows Figure 1 The structural diagram of the A-A section view and the Figure 1 The right side (part not shown) is a schematic structural diagram of an extended cross-sectional view. The insulating glue 20 includes a first insulating glue 21 and a second insulating glue 22; the first insulating glue 21 is connected to the back side of the back contact cell and covers at least part of the position of the gate line 30, and the second insulating glue 22 covers at least part of the surface of the first insulating glue 21.

[0044] The gate lines 30 include two types of gate lines 30 with opposite polarities (for example Figure 1 In order to avoid the short circuit problem of the two gate lines 30 with opposite polarities, some positions of the gate lines 30 include positions where the two gate lines 30 with opposite polarities are prone to short circuit, such as Figure 1 As shown, the partial positions are the ends of the first thin gate 32 and the second thin gate 33. The first insulating glue 21 can also cover other positions of the gate line 30 except the partial positions where short circuits are prone to occur according to the use requirements, and the embodiment of the application does not specifically limit this.

[0045] In the back-contact cell of the embodiment of the present application, in order to avoid short circuit, at least part of the position of the grid line 30 needs to be covered with the first insulating glue 21. The second insulating glue 22 covers at least part of the surface of the first insulating glue 21 in two cases: when the second insulating glue 22 covers part of the surface of the first insulating glue 21, the second insulating glue 22 can prevent the front of the cell body 10 from being scratched by the grid line 30 on the back of the adjacent cell body 10, and can also reduce the amount of the second insulating glue 22, which can save production costs. When the second insulating glue 22 covers all the surfaces of the first insulating glue 21, the second insulating glue 22 has relatively more contact points with the front of the cell body 10, which can more reliably prevent the grid line 30 from scratching the front of the cell body 10.

[0046] Optional, see Figure 3 As shown, the insulating glue 20 includes a first insulating glue 21 and a second insulating glue 22; the first insulating glue 21 is connected to the back side of the back contact battery cell and covers at least part of the position of the gate line 30; the second insulating glue 22 is a convex point structure, and the second insulating glue 22 is connected to at least part of the surface of the first insulating glue 21 away from the battery cell body 10.

[0047] Further references Figure 3 , which shows a structural schematic diagram in which the second insulating glue 22 is connected to four first insulating glues 21 and is not connected to one insulating glue 20.

[0048] In the back-contact battery cell of the embodiment of the present application, in order to avoid short circuit, at least part of the position of the grid line 30 needs to be covered with the first insulating glue 21. The second insulating glue 22 is in the form of a convex structure, which reduces the amount of the second insulating glue 22 used, thereby saving production costs. Furthermore, the connection between the second insulating glue 22 and at least part of the surface of the first insulating glue 21 away from the battery cell body 10 includes two situations: when the second insulating glue 22 is connected to the surface of part of the first insulating glue 21 away from the battery cell body 10, the second insulating glue 22 can prevent the front of the battery cell body 10 from being scratched by the back grid line 30 of the adjacent battery cell body 10, while further reducing the amount of the second insulating glue 22 used, further saving production costs. When the second insulating glue 22 is connected to all surfaces of the first insulating glue 21 away from the battery cell body 10, there are relatively more contact points between the second insulating glue 22 and the front of the battery cell body 10, which can more reliably avoid grid lines 30.

[0049] The line 30 scratches the front surface of the battery cell body 10 .

[0050] Optionally, the embodiment of the present application does not specifically limit the specific structure of the convex structure, the structural size of the convex structure, and the number of convex structures provided on the first insulating adhesive 21. For example, the convex structure is a cylindrical convex point, a polyhedral convex point, a curved convex point, a trapezoidal structure, etc. Figure 3As shown, the size of some convex point structures is relatively large, and the size of other convex point structures is relatively small; one convex point structure is arranged on the first insulating glue 21; and two convex point structures are arranged on the first insulating glue 21.

[0051] Optionally, the Mohs hardness range of the second insulating glue 22 is 2-7. At this time, when the back contact battery cell stacks multiple back contact battery cells during the transfer process, the second insulating glue 22 contacts the front side of the adjacent battery cell body 10. Since the Mohs hardness range of the second insulating glue 22 is 2-7, the second insulating glue 22 is softer than the front side of the battery cell body 10, and the second insulating glue 22 with a Mohs hardness of 2-7 will not scratch the front side of the battery cell body 10.

[0052] Optionally, the thickness of the first insulating adhesive 21 is in the range of 10um to 40um. When the thickness of the first insulating adhesive 21 is in the above range, the amount of the first insulating adhesive 21 can be reduced as much as possible while achieving a good insulating effect, so as to reduce production costs.

[0053] It is understandable that the thickness of the first insulating glue 21 is selected according to the specific usage requirements. For example, the thickness of the first insulating glue 21 is any value of 10um, 15um, 18um, 20um, 25um, 30um, 35um, 38um, and 40um.

[0054] Optionally, the thickness of the second insulating adhesive 22 is in the range of 5um-10um. When the thickness of the second insulating adhesive 22 is in the above range, the second insulating adhesive 22 can prevent the front of the battery cell body 10 from being damaged when in contact with the front of the battery cell body 10, and avoid increasing the thickness of the back contact battery cell.

[0055] It can be understood that the thickness of the second insulating glue 22 is selected according to the specific usage requirements. For example, the thickness of the second insulating glue 22 is any value of 5um, 5.5um, 6um, 6.5um, 7um, 7.5um, 8um, 8.5um, 9um, 9.5um, and 10um.

[0056] Optionally, in order to prevent the insulating glue 20 from scratching the front of the back contact battery cell, after the insulating glue 20 is cured, the Mohs hardness of the end of the insulating glue 20 away from the back contact battery cell is less than the Mohs hardness of the front of the back contact battery cell, and the Mohs hardness of the end of the insulating glue 20 away from the back contact battery cell needs to be in the range of 2-7. Among them, the end of the insulating glue 20 away from the back contact battery cell is used to contact the front of the back contact battery cell.

[0057] touch.

[0058] Optionally, in the case where the insulating glue 20 includes the first insulating glue 21 and the second insulating glue 22, the Mohs hardness range of the second insulating glue 22 is 2-7. When the Mohs hardness of the second insulating glue 22 is within the above range, the Mohs hardness of the second insulating glue 22 is less than the Mohs hardness of the front surface of the battery cell body 10, and the front surface of the battery cell body 10 can be prevented from being scratched when the second insulating glue 22 contacts the front surface of the battery cell body 10.

[0059] It is understandable that the Mohs hardness of the second insulating glue 22 is selected according to specific usage requirements. For example, the Mohs hardness of the second insulating glue 22 is any hardness value of 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, and 7.

[0060] Optional, see Figure 4 , the insulating glue 20 only includes the first insulating glue 21, and the first insulating glue 21 is connected to the back side of the back contact cell and covers at least part of the grid line 30. At this time, in the direction away from the cell body 10, the height of the first insulating glue 21 is greater than the height of the grid line 30, so as to prevent the grid line 30 on the back side of the cell body 10 from scratching the front side of the adjacent cell body 10.

[0061] The insulating glue 20 in the back contact battery cell of the embodiment of the present application only includes the first insulating glue 21. Compared with the technical solution that the insulating glue 20 includes the first insulating glue 21 and the second insulating glue 22, it can also reduce the process of setting the second insulating glue 22, saving production processes and production costs.

[0062] Optionally, when the insulating glue 20 only includes the first insulating glue 21, the Mohs hardness range of the first insulating glue 21 is 2-7. When the Mohs hardness of the first insulating glue 21 is within the above range, the Mohs hardness of the first insulating glue 21 is less than the Mohs hardness of the front side of the battery cell body 10, and the first insulating glue 21 with a Mohs hardness of 2-7 will not scratch the front side of the battery cell body.

[0063] It can be understood that the Mohs hardness of the first insulating glue 21 is selected according to the specific usage requirements. For example, the Mohs hardness of the first insulating glue 21 is any hardness value of 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, and 7.

[0064] Optionally, in a direction away from the battery cell body 10 , the insulating glue 20 has at least two heights, and the height of the insulating glue 20 close to the edge of the battery cell body 10 is greater than or equal to the height of the insulating glue 20 located in the rest of the battery cell body 10 .

[0065] During the process of stacking the back-contact battery cells, when the back-contact battery cells are tilted, the outer periphery of the back-contact battery cells is likely to scratch the front edge of the adjacent back-contact battery cells. Therefore, the front edge of the back-contact battery cells is more likely to be scratched. In the back-contact battery cells of the embodiment of the present application, the insulating glue 20 has at least two heights. The height of the insulating glue 20 close to the edge of the battery cell body 10 is relatively high. When the back-contact battery cells are tilted, there is still a gap between the outer periphery of the back-contact battery cells and the front edge of the back-contact battery cells, which can better prevent the front edge of the back-contact battery cells from being scratched. The height of the insulating glue 20 located in the rest of the battery cell body 10 is relatively low, which can save the amount of insulating glue 20 used, thereby saving production costs.

[0066] Further references Figure 5 As shown, it shows the height H1 of the insulating glue 20 close to the edge of the battery cell body 10 (the insulating glue 20 on the far left), the height of an insulating glue 20 located in the rest of the battery cell body 10 is H2, and H1 is greater than H2; the height of other insulating glues 20 located in the rest of the battery cell body 10 can be the same as H2, or of course can be different.

[0067] Further references Figure 6 As shown, line C represents the schematic diagram of the position of the insulating glue 20 near the edge of the battery cell body 10, that is, line C represents the schematic diagram of the position of the edge of the battery cell body 10. The distance between the insulating glue 20 near the edge of the battery cell body 10 and the edge of the battery cell body 10 is set according to the use requirements, and the embodiment of the present application does not specifically limit this. For example, the distance between the insulating glue 20 near the edge of the battery cell body 10 and the edge of the battery cell body 10 ranges from 2cm to 3cm. It can be understood that the distance between the insulating glue 20 near the edge of the battery cell body 10 and the edge of the battery cell body 10 is specifically selected according to the use requirements. For example, the distance between the insulating glue 20 near the edge of the battery cell body 10 and the edge of the battery cell body 10 is any value of 2cm, 2.1cm, 2.2cm, 2.3cm, 2.4cm, 2.5cm, 2.6cm, 2.7cm, 2.8cm, 2.9cm, and 3cm.

[0068] Optionally, in the direction away from the battery cell body 10, the insulating glue 20 has at least two heights, which can be achieved in a variety of ways, for example, by the size of the aperture of the screen.

[0069] Optionally, in order to better prevent the grid lines 30 from protruding out of the insulating glue 20 and scratching the front surface of the adjacent battery cell body 10 , the height of the insulating glue 20 in the direction away from the battery cell body 10 is greater than the height of all the grid lines 30 .

[0070] Optionally, the height of the insulating glue 20 is in the range of 15um-50um in the direction away from the cell body 10. In the embodiment of the present application, when the height of the insulating glue 20 is in the above range, it can ensure that the height of the insulating glue 20 is higher than the height of the grid line 30, thereby preventing the grid line 30 from scratching the front of the cell body 10 when two adjacent back-contact cells are in contact, and reducing the excessive increase in the thickness of the back-contact cell.

[0071] It can be understood that the height range of the insulating glue 20 is selected according to the specific usage requirements. For example, the height range of the insulating glue 20 is any value among 15um, 17um, 20um, 25um, 30um, 35um, 40um, 45um, 48um, and 50um.

[0072] Optionally, the end of the insulating glue 20 away from the back contact battery cell is UV glue, and the Mohs hardness range of the UV glue is 2-7. The UV glue is softer than the front side of the battery cell body 10, and the UV glue will not scratch the front side of the battery cell body 10, and the UV glue plays a protective role; and the UV glue has a high light transmittance and basically does not affect the light absorption efficiency of the battery component.

[0073] The embodiment of the present application does not specifically limit the selection of the insulating glue 20. For example, when the insulating glue 20 only includes the first insulating glue 21, the first insulating glue 21 is UV glue. For another example, when the insulating glue 20 includes the first insulating glue 21 and the second insulating glue 22, the first insulating glue 21 is green glue and the second insulating glue 22 is UV glue.

[0074] Among them, green glue is green, and the light transmittance of green glue is extremely low, about 40%, and the appearance of the back contact battery cell is visible after lamination. UV glue, also known as photosensitive glue and ultraviolet light curing glue, is a type of adhesive that must be cured by ultraviolet light; UV glue is colorless, with a light transmittance of more than 90%. UV glue does not affect the appearance of the battery component after lamination of the back contact battery cell.

[0075] When the first insulating glue 21 is green glue and the second insulating glue 22 is UV glue, the Mohs hardness range of the UV glue is 2-7. The UV glue is softer than the front side of the battery cell body 10, and the UV glue will not scratch the front side of the battery cell body 10, and the UV glue plays a protective role; and the UV glue has a high light transmittance and basically does not affect the light absorption efficiency of the battery component.

[0076] Optionally, when the first insulating glue 21 is green glue and the second insulating glue 22 is UV glue, a green glue layer and a UV glue layer may be printed on the back of the battery cell body 10 twice, respectively.

[0077] In the back-contact cell of the embodiment of the present application, the height of the insulating glue 20 is greater than the height of the grid line 30 in the direction away from the cell body 10. When multiple back-contact cell sheets are stacked during the transfer process, the insulating glue 20 contacts the front side of the adjacent cell body 10. Since the Mohs hardness range of the end of the insulating glue 20 away from the back-contact cell is 2-7, the insulating glue 20 is softer than the front side of the cell body 10, and the end of the insulating glue 20 with a Mohs hardness of 2-7 will not scratch the front side of the cell body 10; moreover, the grid line 30 will not protrude from the insulating glue 20 and scratch the front side of the adjacent cell body 10, thereby effectively reducing the possibility of front side damage of the back-contact cell during the transfer process.

[0078] After using the back-contact cell, the inventors conducted tests at the component end and found that there was no power attenuation and that the light absorption efficiency of the cell component was basically not affected.

[0079] The embodiment of the present application also provides a solar cell module, which includes the above-mentioned back contact cell sheet.

[0080] Since the solar cell module uses the above-mentioned back-contact cell, in the back-contact cell, in the direction away from the cell body 10, the height of the insulating glue 20 is greater than the height of the grid line 30, the insulating glue 20 contacts the front side of the adjacent cell body 10, and the Mohs hardness range of the end of the insulating glue 20 away from the back-contact cell is 2-7. The insulating glue 20 is softer than the front side of the cell body 10, and the end of the insulating glue 20 with a Mohs hardness of 2-7 will not scratch the front side of the cell body 10; moreover, the grid line 30 will not protrude from the insulating glue 20 and scratch the front side of the adjacent cell body 10, thereby avoiding front side damage of the back-contact cell during the transfer process (surface damage is likely to cause adverse consequences such as poor EL and reduced efficiency), thereby achieving the purpose of improving the appearance quality of the solar cell module and increasing the efficiency of the solar cell module.

[0081] Optionally, the solar cell assembly further comprises a cover plate, a back plate and a polymer layer, and the back contact cell is encapsulated between the cover plate and the back plate through the polymer layer. The back contact cell is encapsulated by the polymer layer, and the insulating glue 20 does not affect the encapsulation of the polymer layer.

[0082] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0083] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. For the embodiments of the device, electronic device, computer-readable storage medium and computer program products containing instructions, since they are basically similar to the method embodiments, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiments.

[0084] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A back contact battery cell, characterized in that: The back contact cell comprises a cell body (10), an insulating glue (20) and a gate line (30), and the insulating glue (20) and the gate line (30) are provided on the back side of the cell body (10); In a direction away from the battery cell body (10), the height of the insulating glue (20) is greater than the height of the grid line (30), and the Mohs hardness range of the end of the insulating glue (20) away from the back contact battery cell is 2-7.

2. The back contact cell according to claim 1, characterized in that: The insulating glue (20) comprises a first insulating glue (21) and a second insulating glue (22); the first insulating glue (21) is connected to the back side of the back contact cell sheet and covers at least part of the position of the gate line (30); and the second insulating glue (22) covers at least part of the surface of the first insulating glue (21).

3. The back contact cell according to claim 1, characterized in that: The insulating glue (20) comprises a first insulating glue (21) and a second insulating glue (22); the first insulating glue (21) is connected to the back side of the back contact battery cell and covers at least part of the position of the gate line (30); the second insulating glue (22) is in a convex point structure, and the second insulating glue (22) is connected to at least part of the surface of the first insulating glue (21) away from the battery cell body (10).

4. The back contact cell according to claim 2 or 3, characterized in that: The Mohs hardness range of the second insulating glue (22) is 2-7.

5. The back contact cell according to claim 1, characterized in that: The insulating glue (20) comprises only a first insulating glue (21), wherein the first insulating glue (21) is connected to the back surface of the back contact cell sheet and covers at least a portion of the gate line (30).

6. The back contact cell according to claim 1, characterized in that: In a direction away from the battery cell body (10), the insulating glue (20) has at least two heights, and the height of the insulating glue (20) close to the edge of the battery cell body (10) is greater than or equal to the height of the insulating glue (20) located in the rest of the battery cell body (10).

7. The back contact cell according to claim 1, characterized in that: In a direction away from the battery cell body (10), the height of the insulating glue (20) ranges from 15um to 50um.

8. The back contact cell according to claim 2 or 3, characterized in that: The thickness of the second insulating glue (22) is in the range of 5um to 10um.

9. The back contact cell according to claim 1, characterized in that: The end of the insulating glue (20) away from the back contact battery sheet is UV glue.

10. A solar cell module, characterized in that: The solar cell module comprises the back contact cell sheet according to any one of claims 1 to 9.

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