Back contact cell and solar cell module

Abstract

The utility model relates to the field of solar photovoltaic technology, in particular to a back contact cell and a solar cell module. The back contact battery piece comprises a battery piece body, a plurality of supporting grid lines and a plurality of isolation bulges, the supporting grid lines are arranged on the back surface of the battery piece body; the isolation protrusions are arranged on the front face of the battery piece body and protrude out of the front face of the battery piece body, and the arrangement direction of the isolation protrusions is parallel to the extending direction of the supporting grid lines. The plurality of isolation projections are projected on the back surface of the cell sheet body, and at least part of the plurality of support grid lines are overlapped with the projection. When a plurality of back contact battery pieces are stacked in the transfer process of the back contact battery pieces, the supporting grid lines do not make contact with the front faces of the battery piece bodies, the supporting grid lines do not scratch the front faces of the adjacent battery piece bodies, and the possibility that the front faces of the back contact battery pieces are scratched in the transfer process is effectively reduced.

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 the light, 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] Obviously, placing the isolation paper on the back contact cell and removing the isolation paper during the subsequent component production will increase the production process and affect the production capacity. When transporting the back contact cell, the isolation paper also needs to be transported, which increases the transportation cost. The isolation paper can only be used a limited number of times, and the discarding of the isolation paper leads to a large waste of costs. In addition, the isolation paper needs to be manually recycled and transported, which further increases the cost waste. 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 when the existing back-contact cell adopts the isolation paper isolation solution, the isolation paper is placed on the back-contact cell, and the isolation paper is removed during the subsequent assembly end production, which increases the production process and affects the production capacity; when transporting the back-contact cell, the isolation paper also needs to be transported, which increases the transportation cost; and the isolation paper has a limited number of uses, and the discarding of the isolation paper leads to a large cost waste, and the isolation paper needs to be manually recovered and transported, further increasing the cost waste.

[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 cell, which includes a cell body, a plurality of supporting grid lines and a plurality of isolation protrusions; the supporting grid lines are arranged on the back side of the cell body; the isolation protrusions are arranged on the front side of the cell body and protrude from the front side of the cell body, and the arrangement direction of the isolation protrusions is parallel to the extension direction of the supporting grid lines; a plurality of the isolation protrusions are projected on the back side of the cell body, and at least part of the plurality of supporting grid lines overlap with the projections.

[0008] Optionally, the isolation protrusion includes a plurality of sub-isolation protrusions, and the sub-isolation protrusions are in a convex point structure; and the plurality of sub-isolation protrusions in any isolation protrusion are arranged at intervals.

[0009] Optionally, in the arrangement direction of the isolation protrusions, multiple sub-isolation protrusions in any isolation protrusion are arranged in sequence; a projection line is made parallel to the arrangement direction of the isolation protrusions, and the projections of two adjacent sub-isolation protrusions on the projection line overlap.

[0010] Optionally, when a cross section is made parallel to the battery cell body, the sub-isolation protrusion has a parallelogram structure; a group of parallel line segments in the sub-isolation protrusion is parallel to the arrangement direction of the isolation protrusion, and another group of parallel line segments in the sub-isolation protrusion is parallel to another group of parallel line segments of an adjacent sub-isolation protrusion.

[0011] Optionally, the isolation protrusion also includes two first end protrusions, one first end protrusion is located at one end of the isolation protrusion, and the other first end protrusion is located at the other end of the isolation protrusion; taking a cross section parallel to the battery cell body, the first end protrusion is in a right-angled triangle structure, the hypotenuse of the right-angled triangle structure faces the sub-isolation protrusion, and is parallel to another set of parallel line segments in the sub-isolation protrusion.

[0012] Optionally, when a cross section is made parallel to the battery cell body, the sub-isolation protrusion is a crescent-shaped structure, and the protrusion direction of multiple crescent-shaped structures in any isolation protrusion is the same, and the protrusion direction is parallel to the arrangement direction of the isolation protrusion.

[0013] Optionally, the isolation protrusions are arranged in straight line segments.

[0014] Optionally, an end surface of the isolation protrusion facing away from the battery cell body is parallel to the battery cell body.

[0015] Optionally, the isolation protrusion is a piece of rubber material.

[0016] In a second aspect, an embodiment of the utility model provides a solar cell assembly, wherein the solar cell assembly includes the back contact cell sheet as described above.

[0017] In the third aspect, the embodiment of the utility model also provides a solar cell assembly, which includes a back-contact cell and a polymer layer; the back-contact cell includes a cell body, a plurality of supporting grid lines and a plurality of traces; the supporting grid lines are arranged on the back side of the cell body; the traces are arranged on the front side of the cell body, and the arrangement direction of the traces is parallel to the extension direction of the supporting grid lines; a plurality of the traces are projected on the back side of the cell body, and at least part of the plurality of supporting grid lines overlaps with the projection; the polymer layer is provided on the light-receiving surface of the cell body, and the polymer layer covers the traces.

[0018] The utility model discloses a back-contact battery cell. When a plurality of back-contact battery cells are stacked during a transfer process, the back side of a back-contact battery cell contacts the front side of another back-contact battery cell. Since an isolation protrusion is provided on the front side of the battery cell body and protrudes from the front side of the battery cell body, the arrangement direction of the isolation protrusion is parallel to the extension direction of the support grid line. A plurality of isolation protrusions are projected on the back side of the battery cell body, and at least part of a plurality of support grid lines are located in the projection, so that when an isolation protrusion on a back-contact battery cell and a support grid line on another back-contact battery cell are in the same direction, the support grid line contacts the corresponding isolation protrusion, or part of the support grid line contacts the corresponding isolation protrusion, and a gap exists between the remaining part of the support grid line and the front side of the battery cell body. When an isolation protrusion on a back-contact battery cell and a support grid line on another back-contact battery cell are in intersection, a plurality of support grid lines and a plurality of isolation protrusions are arranged vertically and horizontally and contact the intersecting parts, and a gap exists between the part of the support grid line that does not contact the isolation protrusion and the front side of the battery cell body. Therefore, the support grid lines will not contact the front side of the battery cell body, and the support grid lines will not scratch the front side of the adjacent battery cell body, effectively reducing the possibility of scratches on the front side of the back contact battery cell during the transfer process.

[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 in accordance with 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 specific implementation methods of the utility model are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] 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.

[0021] Figure 1 This is a schematic diagram of the front structure of the back contact battery cell according to the first embodiment of the utility model;

[0022] Figure 2 for Figure 1 A structural diagram of the enlarged view of part A;

[0023] Figure 3 It is a schematic diagram of a partial front structure of a back contact battery cell according to a second embodiment of the utility model;

[0024] Figure 4 This is a schematic diagram of the front structure of a back-contact battery cell according to a third embodiment of the utility model;

[0025] Figure 5 This is a schematic diagram of the structure of three back contact battery cells stacked and arranged according to an embodiment of the utility model;

[0026] Figure 6 A schematic diagram of the processing of a back contact battery cell according to an embodiment of the utility model;

[0027] Figure 7 This is a schematic diagram of the structure of the stacked arrangement of three back-contact solar cells.

[0028] Description of reference numerals:

[0029] 10-battery body;

[0030] 20 - isolation protrusion; 21 - sub-isolation protrusion; 22 - first end protrusion; 23 - second end protrusion; 24 - third end protrusion;

[0031] 30 – support grid line; 40 – projection line. 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] Back-contact cells have the P region, N region and gate line all located on the back of the cell, and silicon nitride or silicon oxide is used as a passivation layer on the front of the cell. When transporting back-contact cells, multiple back-contact cells need to be stacked. At this time, refer to Figure 7 As shown, the front film layer of the solar cell is easily scratched by the back grid lines of the adjacent solar cell, especially the back support grid lines 30 .

[0034] The present application embodiment discloses a back contact battery sheet, referring to Figure 1 and Figure 5 , Figure 1The front structure schematic diagram of the back contact cell provided in the embodiment of the present application is shown. Figure 5 The schematic diagram of the structure of the stacked arrangement of the back-contact cell provided by the embodiment of the present application is shown. The back-contact cell comprises a cell body 10, a plurality of support grid lines 30 and a plurality of isolation protrusions 20; the support grid lines 30 are arranged on the back of the cell body 10; the isolation protrusions 20 are arranged on the front of the cell body 10 and protrude from the front of the cell body 10, and the arrangement direction of the isolation protrusions 20 is parallel to the extension direction of the support grid lines 30; the plurality of isolation protrusions 20 are projected on the back of the cell body 10, and at least part of the plurality of support grid lines 30 overlaps with the projection. It should be noted that the above-mentioned overlap refers to the overlapping part.

[0035] Specifically, the front side of the cell body 10 is the light-receiving side, and the isolation protrusion 20 is arranged on the front side of the cell body 10. The back side of the cell body 10 is the backlight side, and the grid lines are arranged on the back side of the cell body 10. There are many types of back-contact cells, and the grid lines of different types of back-contact cells are different, wherein the support grid lines 30 are the highest grid lines in the back-contact cell in the direction away from the cell body 10. For example, the back-contact cell includes a main grid line and a fine grid line, and the height of the main grid line is higher than the height of the fine grid line. In this case, the main grid line is the support grid line 30; for example, the back-contact cell includes a main grid line and a fine grid line, and the height of the main grid line is lower than the height of the fine grid line. In this case, the fine grid line is the support grid line 30; for another example, the back-contact cell has no main grid line, and only includes a plurality of fine grid lines, and the fine grid line with the highest height among the plurality of fine grid lines is the support grid line 30.

[0036] Reference Figure 5 As shown, multiple isolation protrusions 20 are projected on the back of the battery cell body 10, and at least part of the multiple support grid lines 30 overlaps with the projection. The above structure includes a variety of situations, for example, the isolation protrusions 20 and the support grid lines 30 are arranged in a one-to-one correspondence, and all the support grid lines 30 overlap with the projection in a one-to-one correspondence. For example, the number of support grid lines 30 is greater than the number of projections, and part of the multiple support grid lines 30 overlaps with the projection, and another part does not overlap with the projection. For another example, the number of support grid lines 30 is less than the number of projections. In this case, part of the multiple support grid lines 30 overlaps with the projection, and another part does not overlap with the projection. Alternatively, all the support grid lines 30 may overlap with the projection in a one-to-one correspondence.

[0037] The back contact cell of the embodiment of the present application refers to Figure 5As shown, when a plurality of back-contact battery cells are stacked during the transfer process, the back side of a back-contact battery cell contacts the front side of another back-contact battery cell. Since the front side of the battery cell body 10 is provided with an isolation protrusion 20, and the isolation protrusion 20 protrudes from the front side of the battery cell body 10, the arrangement direction of the isolation protrusion 20 is parallel to the extension direction of the support grid line 30; the plurality of isolation protrusions 20 are projected on the back side of the battery cell body 10, and at least part of the plurality of support grid lines 30 overlap with the projection, so that the isolation protrusion 20 on one back-contact battery cell and the support grid line 30 on another back-contact battery cell are in contact with each other. When the grid lines 30 are in the same direction, the support grid lines 30 are in contact with the corresponding isolation protrusions 20, or part of the support grid lines 30 are in contact with the corresponding isolation protrusions 20, and there is a gap between the remaining part of the support grid lines 30 and the front surface of the cell body 10; when the isolation protrusions 20 on one back-contact cell and the support grid lines 30 on another back-contact cell are in intersection, multiple support grid lines 30 and multiple isolation protrusions 20 are arranged vertically and horizontally and the intersecting parts are in contact, and there is a gap between the part of the support grid lines 30 that is not in contact with the isolation protrusions 20 and the front surface of the cell body 10. Therefore, the support grid lines 30 will not contact the front surface of the cell body, and the support grid lines 30 will not scratch the front surface of the adjacent cell body 10, effectively reducing the possibility of scratches on the front surface of the back-contact cell during the transfer process.

[0038] Furthermore, when stacking multiple back-contact battery cells in the embodiment of the present application during the transfer process, there is basically no need to consider the setting direction of two adjacent back-contact battery cells, which can reduce the difficulty of the stacking operation and avoid scratches on the front of the battery cell body 10 caused by changes in the stacking direction of the back-contact battery cells.

[0039] Furthermore, when the back-contact battery cells of the embodiment of the present application are stacked during the transfer process, there is no need to set isolation paper between two adjacent back-contact battery cells, which can avoid the technical problems of placing isolation paper on the back-contact battery cells and removing the isolation paper during subsequent component production, which increase the production process and affect the production capacity; avoid the technical problem of high transportation costs caused by the need to transport isolation paper when transporting the back-contact battery cells; and avoid the technical problem of large cost waste caused by discarding isolation paper, and the need for manual recovery and transportation of isolation paper, further increasing cost waste.

[0040] Optionally, the embodiment of the present application does not specifically limit the manner in which the isolation protrusion 20 is disposed on the battery cell body 10. For example, the isolation protrusion 20 is printed on the front surface of the battery cell body 10; for another example, the isolation protrusion 20 is disposed on the front surface of the battery cell body 10 by inkjet printing.

[0041] Optional, see Figure 1As shown, the isolation protrusion 20 includes a plurality of sub-isolation protrusions 21, and the sub-isolation protrusions 21 are in a convex point structure; the plurality of sub-isolation protrusions 21 in any isolation protrusion 20 are arranged at intervals.

[0042] In the back-contact cell of the embodiment of the present application, the multiple sub-isolation protrusions 21 in any isolation protrusion 20 are arranged at intervals, which can reduce the material cost of the isolation protrusion 20 and the shading area, thereby ensuring the photoelectric conversion efficiency of the back-contact cell.

[0043] Optional, see Figure 2 As shown, in the arrangement direction of the isolation protrusions 20, multiple sub-isolation protrusions 21 in any isolation protrusion 20 are arranged in sequence; a projection line 40 is made parallel to the arrangement direction of the isolation protrusions 20, and the projections of two adjacent sub-isolation protrusions 21 on the projection line overlap.

[0044] At this time, in the arrangement direction of the isolation protrusions 20, the multiple sub-isolation protrusions 21 in any isolation protrusion 20 are arranged inseparably. That is to say, in the arrangement direction of the isolation protrusions 20, although the multiple sub-isolation protrusions 21 are arranged at intervals, in the arrangement direction of the isolation protrusions 20, the multiple sub-isolation protrusions 21 are in a continuous and uninterrupted long strip structure. At this time, when multiple back-contact battery cells are stacked, the isolation protrusions 20 on one back-contact battery cell and the support grid lines 30 on another back-contact battery cell can maintain continuous contact, and the front side of the back-contact battery cell and the back side of the back-contact battery cell have a more stable isolation effect, effectively preventing the support grid lines 30 from scratching the front side of the adjacent battery cell body 10.

[0045] Furthermore, during the production process of the back contact cell, the back side of the cell body 10 is provided with the support grid line 30 and needs to be tested. During the test, the front side of the back contact cell is directed toward the operating table and in contact with the operating table, and the test probe is used to support the support grid line 30. Since in the arrangement direction of the isolation protrusions 20, the multiple sub-isolation protrusions 21 in any isolation protrusion 20 are arranged inseparably, refer to Figure 2 As shown, in the B direction, the multiple sub-isolation protrusions 21 corresponding to the support grid lines 30 support the support grid lines 30 continuously and uninterruptedly, and the multiple sub-isolation protrusions 21 are arranged as an uninterrupted force-bearing interval similar to a long strip, that is, in the B direction, the sub-isolation protrusions 21 provide a continuous distribution of force points. Figure 6As shown, when the test probe is used to press against the support grid line 30, the force direction of the battery cell body 10 and the support grid line 30 is shown by the arrow E, and the multiple sub-isolation protrusions 21 provide a continuous force point distribution, which forms a long strip support area. The multiple sub-isolation protrusions 21 form continuous support for the support grid line 30 and the battery cell body 10 located between the multiple sub-isolation protrusions 21 and the support grid line 30, so that the back contact battery cell will not cause hidden cracks due to the test probe pressing against the support grid line 30 during battery testing.

[0046] Moreover, before the back contact cell is packaged, an insulating glue needs to be printed on the support grid line 30, and the printing direction of the insulating glue is the same as the setting direction of the support grid line 30. The insulating glue is generally screen-printed, and the multiple sub-isolation protrusions 21 corresponding to the support grid line 30 support the support grid line 30 continuously and uninterruptedly. The sub-isolation protrusions 21 provide a continuous distribution of force points. The printing of the insulating glue allows the back contact cell to be stressed, and the multiple sub-isolation protrusions 21 continuously and uninterruptedly support the back contact cell, which can avoid the back contact cell from being deformed by depression due to stress, resulting in hidden cracks.

[0047] Further, see Figure 6 , arrow D is the printing direction, arrow E is the force direction of the back contact cell when printing, and arrow E is the force direction of the back contact cell when the test probe presses against the support grid line 30, Figure 6 It shows a schematic diagram of a plurality of sub-isolation protrusions 21 in an embodiment of the present application providing continuous and uninterrupted support for the back contact battery sheet and providing a continuous and uninterrupted distribution of force points.

[0048] It is understandable that the sub-isolation protrusion 21 may have a variety of structures, and the embodiment of the present application does not specifically limit the structure of the sub-isolation protrusion 21.

[0049] Optionally, in one embodiment, referring to Figure 1 and Figure 2 As shown, the sub-isolation protrusion 21 is parallel to the battery cell body 10 in a cross section and is parallelogram-shaped; a group of parallel line segments in the sub-isolation protrusion 21 is parallel to the arrangement direction of the isolation protrusion 20, and another group of parallel line segments in the sub-isolation protrusion 21 is parallel to another group of parallel line segments in the adjacent sub-isolation protrusion 21. The above structure of the embodiment of the present application is further referred to Figure 2 As shown, in the schematic diagram of the front structure of the battery cell body 10 , the projections of the plurality of parallelogram-shaped sub-isolation protrusions 21 on the projection line 40 overlap.

[0050] Further, see Figure 2As shown, when the projections of the projection line 40 of the multiple sub-isolation protrusions 21 in any isolation protrusion 20 overlap, there are various positional relationships between two adjacent sub-isolation protrusions 21, which are not specifically limited in the present application. Figure 2 In the figure, from top to bottom, the first sub-isolation protrusion 21, the second sub-isolation protrusion 21, and the third sub-isolation protrusion 21 are arranged along a straight line, that is, they are arranged parallel to the projection line 40. When the first sub-isolation protrusion 21, the second sub-isolation protrusion 21, and the third sub-isolation protrusion 21 are projected on the projection line 40, the lower right tip of the first sub-isolation protrusion 21 close to the second sub-isolation protrusion 21 coincides with the upper left tip of the second sub-isolation protrusion 21 close to the first sub-isolation protrusion 21; the projection of the lower right tip of the second sub-isolation protrusion 21 close to the third sub-isolation protrusion 21 on the projection line 40 is located inside the projection of the third sub-isolation protrusion 21 on the projection line 40. For further reference, Figure 6 As shown, the force direction of the battery cell body 10 and the support grid line 30 is shown by arrow E. In the arrangement direction of the isolation protrusion 20, multiple sub-isolation protrusions 21 are arranged inseparable. The multiple sub-isolation protrusions 21 can provide continuous support and continuous force point distribution for the support grid line 30 and the battery cell body 10.

[0051] Optional, see Figure 1 and Figure 2 As shown, the isolation protrusion 20 also includes two first end protrusions 22, one first end protrusion 22 is located at one end of the isolation protrusion 20, and the other first end protrusion 22 is located at the other end of the isolation protrusion 20; the first end protrusion 22 is in a right triangle structure when the cross section is made parallel to the battery cell body 10, and the hypotenuse of the right triangle structure faces the sub-isolation protrusion 21 and is parallel to another group of parallel line segments in the sub-isolation protrusion 21. In the above structure of the embodiment of the present application, the edge of the isolation protrusion 20 is a straight line segment. When multiple back contact battery cells are stacked, the sub-isolation protrusion 21 has a sharp tip relative to the edge, and the edge portion is not easy to scratch other back contact battery cells.

[0052] Furthermore, if the plurality of sub-isolation protrusions 21 in any isolation protrusion 20 are arranged in a non-separated manner, then there are various positional relationships between the first end protrusion 22 and the adjacent sub-isolation protrusion 21, and the present application is not specifically limited to this in the embodiments. For example, in the projection line 40, the lower right tip of the first end protrusion 22 close to the sub-isolation protrusion 21 coincides with the upper left tip of the sub-isolation protrusion 21 close to the first end protrusion 22. For another example, referring to Figure 2 As shown, the projection of the lower right tip of the first end protrusion 22 close to the sub-isolating protrusion 21 in the projection line 40 is located inside the projection of the sub-isolating protrusion 21 in the projection line 40 .

[0053] Optionally, in another embodiment, referring to Figure 3 As shown, in a cross section parallel to the battery cell body 10 , the sub-isolation protrusions 21 are in a crescent-shaped structure, and the protruding directions of the multiple crescent-shaped structures in any isolation protrusion 20 are the same, and the protruding direction is parallel to the arrangement direction of the isolation protrusions 20 .

[0054] Furthermore, the convex direction of the crescent-shaped structure refers to the direction in which the crescent-shaped structure bulges, referring to Figure 3 As shown, it is the direction of arrow C, and the direction of arrow C is parallel to the arrangement direction of the isolation protrusions 20.

[0055] Furthermore, if the plurality of sub-isolation protrusions 21 in any isolation protrusion 20 are arranged in a non-separated manner, the sub-isolation protrusions 21 have various positional relationships, which are not specifically limited in the present application. Figure 3 As shown, from top to bottom, the projection of the end of the second crescent-shaped structure in the protruding direction on the projection line 40 coincides with the projection of the tip of the first crescent-shaped structure on the projection line 40. Alternatively, referring to Figure 3 As shown, the projection of the end of the third crescent-shaped structure in the protruding direction on the projection line 40 is within the projection of the second crescent-shaped structure on the projection line 40 .

[0056] Optional, see Figure 3 As shown, the isolation protrusion 20 also includes a second end protrusion 23 and a third end protrusion 24, the second end protrusion 23 is located at one end of the isolation protrusion 20, and the third end protrusion 24 is located at the other end of the isolation protrusion 20; the second end protrusion 23 is a rectangular structure, and a groove is provided at the end of the rectangular structure facing the sub-isolation protrusion 21, and the concave direction of the groove is the same as the protruding direction of the crescent-shaped structure; the end of the third end protrusion 24 facing the sub-isolation protrusion 21 is an arc-shaped structure, and the end of the third end protrusion 24 facing the ion isolation protrusion 21 is a straight line segment.

[0057] At this time, there are various positional relationships between the second end protrusion 23 and the adjacent sub-isolation protrusion 21, and between the third end protrusion 24 and the adjacent sub-isolation protrusion 21, which are not specifically limited in this embodiment of the present application. For example, the projection of the end of the protruding direction of the crescent-shaped structure on the projection line 40 coincides with the projection of the side of the second end protrusion 23 close to the sub-isolation protrusion 21 on the projection line 40. Or, refer to Figure 3 As shown, the projection of the end of the crescent-shaped structure in the protruding direction on the projection line 40 is located within the projection of the second end protrusion 23 on the projection line 40 .

[0058] Optional, see Figure 4As shown, the isolation protrusion 20 is in a long strip structure. The isolation protrusion 20 in the long strip structure is arranged corresponding to the support grid line 30. When multiple back contact cells are stacked, the isolation protrusion 20 in the long strip structure can provide a larger and continuous isolation contact area, so that the front side of the back contact cell sheet and the back side of the back contact cell sheet have a more stable isolation effect.

[0059] Optional, see Figure 4 As shown, the end surface of the isolation protrusion 20 facing away from the battery cell body 10 is parallel to the battery cell body 10. At this time, the isolation protrusion 20 can stably support the battery cell body 10, for example, so that the battery cell body 10 remains horizontal. When testing is performed after the support grid line 30 is set on the back of the battery cell body 10, and when insulating glue needs to be printed on the support grid line 30, the isolation protrusion 20 can play a stable supporting role to avoid deflection, etc.

[0060] Optionally, the isolation protrusion 20 is made of a silicone material. In this case, the isolation protrusion 20 is relatively soft, and the isolation protrusion 20 will not damage the support grid line 30 when in contact with the support grid line 30. Moreover, the isolation protrusion 20 being made of a silicone material will not substantially affect illumination, thereby avoiding optical loss.

[0061] Reference Figure 5 As shown, during the transfer process of the back-contact cell of the embodiment of the present application, when multiple back-contact cell sheets are stacked, the isolation protrusion 20 on one back-contact cell sheet and the support grid line 30 on another back-contact cell sheet are arranged in the same direction, the isolation protrusion 20 is in contact with the corresponding support grid line 30, the support grid line 30 will not contact the front side of the cell body, and the support grid line 30 will not scratch the front side of the adjacent cell body 10, effectively reducing the possibility of scratches on the front side of the back-contact cell sheet during the transfer process.

[0062] The embodiment of the present application also discloses a solar cell assembly, which includes the back contact cell sheet as described above. Optionally, the solar cell assembly may also include a cover plate and a back plate, wherein the back contact cell sheet is arranged between the cover plate and the back plate.

[0063] In an embodiment of the present application, a solar cell module uses the above-mentioned back-contact cell sheet. During the transfer process of the above-mentioned back-contact cell sheet, when multiple back-contact cell sheets are stacked, the isolation protrusion 20 on one back-contact cell sheet and the support grid line 30 on another back-contact cell sheet are arranged in the same direction, and the isolation protrusion 20 is in contact with the corresponding support grid line 30. The support grid line 30 will not contact the front side of the cell sheet body, and the support grid line 30 will not scratch the front side of the adjacent cell sheet body 10, thereby avoiding front side damage of the back-contact cell sheet during the transfer process (surface damage is likely to cause adverse consequences such as poor EL and decreased efficiency), thereby achieving the purpose of improving the appearance quality of the solar cell module and increasing the efficiency of the solar cell module.

[0064] Optionally, the solar cell module further includes an adhesive film, and the back contact cell is encapsulated between the cover plate and the back plate through the adhesive film. After the back contact cell is encapsulated by the adhesive film, the shape of the isolation protrusion 20 does not change, and the isolation protrusion 20 does not affect the encapsulation of the adhesive film, and basically does not affect the light transmittance of the adhesive film, and thus does not affect the efficiency of the solar cell module.

[0065] Optionally, the embodiment of the present application also provides another photovoltaic module, including the back-contact cell in the above embodiment. In the embodiment of the other photovoltaic module, the isolation protrusion is made of a material that is easy to vaporize (a low-boiling point material), such as polyvinyl alcohol (PVA), the melting point of PVA is about 100°C, and the boiling point of PVA is about 180°C. When the cell is packaged and transported in a room temperature environment, since the ambient temperature is lower than the melting point of the isolation protrusion, the shape of the isolation protrusion is relatively stable, which can play an effective isolation and protection role for the light-receiving surface of the cell. When the isolation protrusion needs to be removed when isolation protection is not required, the solar cell can be heated to a temperature above the boiling point of the isolation protrusion, so that the isolation protrusion is vaporized and removed. For example, if PVA material is used, the subsequent heating temperature can be greater than 180°C.

[0066] However, the heating process does not completely vaporize the isolation protrusions. Some of them will remain on the surface of the battery cell body to form multiple traces, which can be used as marking points for subsequent processes. For example, the trace can be used as a marking point when preparing a polymer layer on the surface of the battery cell. The polymer layer can be, for example, an EVA layer or a POE layer or a composite layer of the two. For another example, the battery cell, polymer layer, glass, etc. need to be subjected to a hot pressing process to form a photovoltaic module. The trace can be used as a marking point during the hot pressing process.

[0067] In the embodiment of another photovoltaic module, when the back-contact cell stacks multiple back-contact cell sheets during the transfer process, the back side of one back-contact cell sheet contacts the front side of another back-contact cell sheet. Since the front side of the cell sheet body 10 is provided with an isolation protrusion 20, and the isolation protrusion 20 protrudes from the front side of the cell sheet body 10, the arrangement direction of the isolation protrusion 20 is parallel to the extension direction of the support grid line 30; the multiple isolation protrusions 20 are projected on the back side of the cell sheet body 10, and at least part of the multiple support grid lines 30 overlap with the projection, so that the isolation protrusion 20 on one back-contact cell sheet and the other back-contact cell sheet are in contact with each other. When the support grid lines 30 on the cell sheet are in the same direction, the support grid lines 30 are in contact with the corresponding isolation protrusions 20, or part of the support grid lines 30 are in contact with the corresponding isolation protrusions 20, and there is a gap between the remaining part of the support grid lines 30 and the front of the cell body 10; when the isolation protrusions 20 on a back contact cell sheet and the support grid lines 30 on another back contact cell sheet are in intersection, multiple support grid lines 30 and multiple isolation protrusions 20 are arranged vertically and horizontally and the intersecting parts are in contact, and there is a gap between the part of the support grid lines 30 that is not in contact with the isolation protrusions 20 and the front of the cell body 10. Therefore, the support grid lines 30 will not contact the front of the cell body, and the support grid lines 30 will not scratch the front of the adjacent cell body 10, effectively reducing the possibility of scratches on the front of the back contact cell during the transfer process. In addition, the isolation protrusions are made of materials that are easy to vaporize (low boiling point materials), and the isolation protrusions can be removed by heating before forming the assembly, leaving multiple traces, which can be used as marking points in the assembly process. Preferably, the trace is a trace of straight line segment arrangement.

[0068] 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.

[0069] 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.

[0070] 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), a plurality of support grid lines (30) and a plurality of isolation protrusions (20); the support grid lines (30) are arranged on the back side of the cell body (10); the isolation protrusions (20) are arranged on the front side of the cell body (10) and protrude from the front side of the cell body (10); the arrangement direction of the isolation protrusions (20) is parallel to the extension direction of the support grid lines (30); The plurality of isolation protrusions (20) are projected onto the back surface of the battery cell body (10), and at least a portion of the plurality of support grid lines (30) overlaps with the projection.

2. The back contact cell according to claim 1, characterized in that: The isolation protrusion (20) comprises a plurality of sub-isolation protrusions (21), and the sub-isolation protrusions (21) are in a convex point structure; the plurality of sub-isolation protrusions (21) in any one of the isolation protrusions (20) are arranged at intervals.

3. The back contact cell according to claim 2, characterized in that: In the arrangement direction of the isolation protrusions (20), a plurality of the sub-isolation protrusions (21) in any isolation protrusion (20) are arranged in sequence; a projection line is made parallel to the arrangement direction of the isolation protrusions (20), and the projections of two adjacent sub-isolation protrusions (21) on the projection line overlap.

4. The back contact cell according to claim 3, characterized in that: Taking a cross section parallel to the battery cell body (10), the sub-isolation protrusion (21) presents a parallelogram structure; a group of parallel line segments in the sub-isolation protrusion (21) is parallel to the arrangement direction of the isolation protrusion (20), and another group of parallel line segments in the sub-isolation protrusion (21) is parallel to another group of parallel line segments of an adjacent sub-isolation protrusion (21).

5. The back contact cell according to claim 4, characterized in that: The isolation protrusion (20) further comprises two first end protrusions (22), one of the first end protrusions (22) being located at one end of the isolation protrusion (20), and the other first end protrusion (22) being located at the other end of the isolation protrusion (20); Taking a cross section parallel to the battery cell body (10), the first end protrusion (22) is in a right triangle structure, the hypotenuse of which faces the sub-isolation protrusion (21) and is parallel to another group of parallel line segments in the sub-isolation protrusion (21).

6. The back contact cell according to claim 3, characterized in that: Taking a cross section parallel to the battery cell body (10), the sub-isolation protrusions (21) are in a crescent-shaped structure, and the protrusion directions of the multiple crescent-shaped structures in any one of the isolation protrusions (20) are the same, and the protrusion directions are parallel to the arrangement direction of the isolation protrusions (20).

7. The back contact cell according to claim 1, characterized in that: The isolation protrusions (20) are arranged in straight line segments.

8. The back contact cell according to claim 1, characterized in that: The end surface of the isolation protrusion (20) facing away from the battery cell body (10) is parallel to the battery cell body (10).

9. The back contact cell according to claim 1, characterized in that: The isolation protrusion (20) is a piece of rubber material.

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.

11. A solar cell module, characterized in that: The solar cell assembly comprises a back contact cell sheet and a polymer layer; The back contact battery cell comprises a battery cell body (10), a plurality of support grid lines (30) and a plurality of traces; the support grid lines (30) are arranged on the back side of the battery cell body (10); the traces are arranged on the front side of the battery cell body (10), and the arrangement direction of the traces is parallel to the extension direction of the support grid lines (30); The plurality of traces are projected on the back of the battery cell body (10), and at least a portion of the plurality of support grid lines (30) overlaps with the projection; The polymer layer is provided on the front side of the battery cell body (10) of the battery cell body, and the polymer layer covers the trace.

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