CN217588948U

CN217588948U - Back contact solar cell, cell module, electrode structure and screen printing plate thereof

Info

Publication number: CN217588948U
Application number: CN202220818787.2U
Authority: CN
Inventors: 李中兰; 张云海; 鲁伟明; 李华; 靳玉鹏
Original assignee: Taizhou Longi Solar Technology Co Ltd
Current assignee: Taizhou Longi Solar Technology Co Ltd
Priority date: 2022-04-08
Filing date: 2022-04-08
Publication date: 2022-10-14
Anticipated expiration: 2032-04-08

Abstract

The utility model provides a back contact solar cell and battery pack, electrode structure and half tone thereof relates to solar photovoltaic technology field. The electrode structure comprises at least one edge electrode closest to the edge of the back contact solar cell body; the edge electrode includes: the edge collector grid lines are used for collecting carriers of the back contact solar cell body; an edge busbar extending along an edge of the back contact solar cell body; the edge busbar grid line is intersected with the edge busbar grid line; the edge electrode disc is positioned on one side, far away from the edge, of the edge busbar line and has a first interval with the edge busbar line; and the auxiliary grid line is connected with the edge bus grid line and the edge electrode disk. The utility model discloses reduced the cracked probability of back contact solar cell, especially reduced the cracked probability of near the regional area in series connection border.

Description

Back contact solar cell, cell module, electrode structure and screen printing plate thereof

Technical Field

The utility model relates to a solar photovoltaic technology field especially relates to back of body contact solar cell and battery pack, electrode structure and half tone thereof.

Background

The back contact solar cell has a wide application prospect due to higher photoelectric conversion efficiency.

However, the conventional back contact solar cell is easily broken during the process of forming the cell module, and particularly, the edge of the back contact solar cell is easily broken.

SUMMERY OF THE UTILITY MODEL

The utility model provides a back of body contact solar cell and battery pack, electrode structure and half tone thereof aims at solving back of body contact solar cell and at the in-process that forms battery pack, breaks easily, especially back of body contact solar cell's the easy cracked problem in edge.

The utility model discloses a first aspect provides a back of body contact solar cell's electrode structure, include:

the electrode structure is positioned on the back side of the back contact solar cell body;

the electrode structure comprises at least one edge electrode closest to the edge of the back contact solar cell body;

the edge electrode includes:

the edge collector grid lines are used for collecting carriers of the back contact solar cell body;

an edge bus bar line extending along an edge of the back contact solar cell body; the edge busbar grid line is intersected with the edge busbar grid line;

the edge electrode disc is positioned on one side, far away from the edge, of the edge bus grid line and has a first interval with the edge bus grid line;

and (c) a second step of,

and the auxiliary grid line is connected with the edge bus grid line and the edge electrode disk.

The embodiment of the utility model provides an in, be closest to the border electrode dish at back contact solar cell body back border, connect on the auxiliary grid line, the border is converged the grid line and is passed through the auxiliary grid line and connect on the border electrode dish, the border electrode dish does not set up on the border is converged the grid line, and the border electrode dish is located the border and is converged the grid line and keep away from one side at border, and converge the grid line with the border and have first interval, the border electrode dish is exactly the position of the electrically conductive interconnection of follow-up formation battery pack, that is to say, still there is great distance between border electrode dish and the border, and then at formation battery pack's in-process, the position of electrically conductive interconnection between the back contact solar cell all with still have great distance between the border at the battery body back, no matter be electrically conductive interconnection or the lamination can avoid stress concentration at the border of battery body, thereby reduce the cracked probability of back contact solar cell, especially reduced near regional cracked probability in the back contact solar cell of border. Meanwhile, in the edge electrode: the first interval is arranged between the edge electrode disk and the edge busbar line, so that the edge electrode disk is basically flush with the surrounding electrode area, almost no height difference or very small height difference exists, the stress in the lamination or conductive interconnection process is reduced, the probability of breakage of the back contact solar cell can be reduced, and particularly, the probability of breakage of the area near the edge in the back contact solar cell is reduced.

Optionally, a plurality of edge electrode disks are discontinuously distributed in the direction parallel to the extension direction of the middle part of the edge busbar line.

Optionally, in a direction parallel to the extension of the middle portion of the edge busbar line, the edge electrode pads distributed discontinuously are collinear.

Optionally, the electrode structure further includes: a proximate electrode adjacent to and spaced from the edge electrode;

the proximate electrode includes: the adjacent bus grid line is intersected with the adjacent power collection grid line;

in the adjacent electrodes, in the extending direction of the middle part of the edge busbar line, at least one adjacent collector grid line adjacent to the end part of the edge electrode disk has a bending section which bends and extends into the first interval at one end of the adjacent busbar grid line far away from the intersection of the adjacent busbar grid line.

Optionally, the first interval is greater than or equal to 0.5mm, and/or the length of the edge electrode disk is greater than or equal to 0.5mm; the length direction of the edge electrode disc is parallel to the extending direction of the middle part of the edge busbar line.

Optionally, the end of the edge electrode disk is further connected to a second grid line.

Optionally, the extension length of the bending section is greater than or equal to half of the length of the edge electrode disk; the length direction of the edge electrode disc and the extension length direction of the bending section are parallel to the extension direction of the middle part of the edge busbar line.

Optionally, the line width of the bending section is 20-300um.

Optionally, the shape of the bending section is: l-form or F-form.

Optionally, the line width of the auxiliary gate line is greater than the line width of the edge collector gate line.

Optionally, the first spacing is greater than or equal to 0.1mm.

Optionally, the first spacing is greater than or equal to 0.2mm.

Optionally, the proximate electrode further comprises: an adjacent electrode disk disposed on the adjacent busbar line; and in the direction vertical to the extending direction of the middle part of the edge busbar line, the adjacent electrode disk and the edge electrode disk are collinear.

Optionally, in the edge bus line: the part of the chamfer positioned on the back surface is an arc line segment, and the rest part is a straight line segment;

and the line width of the arc line segment is increased from the direction far away from the edge electrode disk to the direction close to the edge electrode disk.

Optionally, the line width of the arc line segment gradually increases from a direction away from the edge electrode disk to a direction close to the edge electrode disk.

Optionally, a line width of a portion, closest to the edge electrode disk, of the arc line segment is equal to a line width of the straight line segment;

and/or the line width of the part, farthest from the edge electrode disk, of the arc line segment is equal to the line width of the edge collecting grid line.

Optionally, the extending direction of the edge collector grid line and the extending direction of the middle part of the edge collector grid line are perpendicular to each other.

Optionally, the electrode structure further includes: with at least one middle part electrode that border electrode interval set up, every middle part electrode all includes: the middle electrode disk is arranged on the middle bus grid line; the middle bus grid line and the edge bus grid line are distributed in parallel;

the distance between the edge bus grid line and the adjacent middle bus grid line is greater than the distance between the adjacent middle bus grid lines; the direction of the distance is vertical to the extending direction of the middle part of the edge busbar line;

and the distance between the edge electrode disk and the adjacent middle electrode disk is equal to the distance between the adjacent middle electrode disks.

Optionally, the end of the edge electrode disk is further connected to a second grid line; the part of the second grid line extending along the first direction is collinear with the middle collecting grid line adjacent to the first direction; the first direction is perpendicular to the extending direction of the middle part of the edge busbar line.

Optionally, the plurality of edge electrode disks and the plurality of middle electrode disks are distributed in an interdigital array to form an electrode disk array;

the electrode disk array is symmetrically distributed along the central line of the electrode disk array; the center line has at least a portion parallel to the extension of the middle portion of the edge busbar line.

Optionally, the edge collecting grid line is: the edge of the silk-screen printing collects the grid line, or the edge of the electric plating collects the grid line;

and/or, the auxiliary grid line is: auxiliary grid lines of screen printing or auxiliary grid lines of electroplating;

and/or, the edge busbar line is: screen printed edge bus bars, or plated edge bus bars;

and/or the edge electrode disk is: screen printed edge electrode pads.

Optionally, the edge collecting grid line is: the edge of the silk-screen printing collects the grid line, the said auxiliary grid line is: the supplementary grid line of screen printing, the border busbar line is: the border of screen printing converges the grid line, the border electrode disc is: a screen printed edge electrode disk;

or, the edge collecting grid line is: the edge of electroplating collects the grid line, supplementary grid line is: the auxiliary grid line of electroplating, the border busbar line does: the border of electroplating converges grid line, the border electrode disc is: screen printed edge electrode pads.

In a second aspect of the present invention, an electrode screen of a back contact solar cell is provided, where the electrode screen of the back contact solar cell is used for printing an electrode structure of the back contact solar cell as described in the previous paragraph.

A third aspect of the present invention provides a back contact solar cell, including the electrode structure of the back contact solar cell as described in any of the above.

Optionally, the back contact solar cell includes: whole cells or sliced cells;

and the cutting line on the back of the sliced battery body is vertical to the extending direction of the middle part of the edge busbar line.

The utility model discloses a fourth aspect provides a battery pack, include: a plurality of back contact solar cells as described above;

each back contact solar cell is electrically connected at least through the edge electrode disk.

The fifth aspect of the present invention provides a method for producing an electrode structure of a back contact solar cell, comprising:

forming at least one edge electrode closest to the edge of the back contact solar cell body on the back surface of the back contact solar cell main body;

the edge electrode includes:

an edge busbar extending along an edge of the back contact solar cell body; the edge busbar line is intersected with the edge busbar line;

the edge electrode disc is positioned on one side, far away from the edge, of the edge busbar line and has a first interval with the edge busbar line;

and the number of the first and second groups,

Optionally, the edge electrode disk is prepared first, and then the edge collector grid line is prepared.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the description of the embodiments of the present invention will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive labor.

Fig. 1 shows a schematic structural diagram of an electrode structure of a first back contact solar cell in an embodiment of the present invention;

fig. 2 is a schematic partial structure enlargement of an electrode structure of a first back contact solar cell in an embodiment of the present invention;

fig. 3 shows a schematic structural diagram of an electrode structure of a second back contact solar cell in an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a first back contact solar cell string in an embodiment of the present invention;

fig. 5 is a schematic structural diagram of a second back contact solar cell string according to an embodiment of the present invention;

fig. 6 is a partial schematic structural enlargement of an electrode structure of a second back contact solar cell in an embodiment of the present invention;

fig. 7 is a partial schematic structural enlargement of an electrode structure of a third back contact solar cell in an embodiment of the present invention;

fig. 8 is a partial schematic structural enlargement of an electrode structure of a fourth back contact solar cell in an embodiment of the present invention;

fig. 9 is a schematic structural diagram illustrating an electrode structure of a third back contact solar cell in an embodiment of the present invention;

fig. 10 shows a schematic structural diagram of a fourth back contact solar cell in an embodiment of the present invention.

Description of the figures:

11-edge electrode, 111-edge collector grid line, 112-edge collector grid line, 1121-arc line segment, 1122-straight line segment, 113-edge electrode disk, 114-auxiliary grid line, 115-second grid line, 12-adjacent electrode, 121-adjacent collector grid line, 1211-bending segment, 1212-back hook, 122-adjacent collector grid line, 123-adjacent electrode disk, 13-middle electrode, 131-middle collector grid line, 132-middle collector grid line, 133-middle electrode disk, 2-conductive interconnection.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by a person skilled in the art without making creative efforts belong to the protection scope of the present invention.

Fig. 1 shows a schematic structural diagram of an electrode structure of a first back contact solar cell in an embodiment of the present invention. Fig. 2 shows a schematic enlarged partial structure of an electrode structure of a first back contact solar cell in an embodiment of the present invention. Fig. 3 shows a schematic structural diagram of an electrode structure of a second back contact solar cell in an embodiment of the present invention. Fig. 4 shows a schematic structural diagram of a first back contact solar cell string in an embodiment of the present invention. Fig. 5 shows a schematic structural diagram of a second back contact solar cell string according to an embodiment of the present invention. Fig. 2 may be an enlarged schematic view of a portion outlined by a dashed box in fig. 1.

The back contact solar cell body is as follows: the back contact solar cell is in a portion other than the electrode structure. The main functions of the back contact solar cell body are as follows: separating and transporting carriers. The electrode structure of the back contact solar cell is mainly used for collecting carriers.

If there is a surface mainly receiving light in the back contact solar cell main body, the surface mainly receiving light in the back contact solar cell main body is distributed opposite to the back surface. As shown in fig. 1, 2, 3, 4, and 5, the electrode structure of the back contact solar cell is located on the back surface side of the back contact solar cell body. The electrode structure may comprise at least two sets of electrodes of opposite polarity spaced apart. One of the two groups of electrodes with opposite polarities is a positive electrode, the other group is a negative electrode, and the positive electrode and the negative electrode are distributed on the back surface in an interdigital manner.

Note that the type of the back contact solar cell is not particularly limited. For example, the back contact solar cell may be an IBC (indirect back contact) cell.

The back contact solar cell body edge can be: and the edge is arranged on the backlight surface of the solar cell body. The electrode structure includes at least one edge electrode closest to an edge of the back contact solar body. For example, in fig. 1, 2, 3, 4, and 5, the edge electrode 11 is the leftmost electrode and the rightmost electrode. In a back contact solar cell: the number of edge electrodes 11 is less than or equal to the number of edges.

Each edge electrode 11 includes: a plurality of edge collector grid lines 111, and the number of edge collector grid lines 111 is not particularly limited. The edge collector grid lines 111 are mainly used for collecting carriers of the back contact solar body. The edge collector grid line 111 may be linear or arc-shaped.

Each edge electrode 11 further includes: and an edge bus line 112 electrically connected to or intersecting the edge collector line 111. The edge bus bar line 112 is mainly used to collect carriers on the edge bus bar line 111 and transfer the collected carriers to the edge electrode pad 113. The edge bus lines 112 extend along the edges of the back contact solar cell body. As shown in fig. 1, the edge bus line 112 has at least a portion parallel to the dotted line L. The shape of the edge bus line 112 may be linear or arc.

Each edge electrode 11 further includes: at least one edge electrode disk 113. The shape of the edge electrode pad 113 may be a rectangle, etc., which is not limited in the embodiments of the present invention. Optionally, the width of the edge electrode pad 113 may be 500 to 2000um, and the direction of the width of the edge electrode pad 113 is perpendicular to the direction of the edge of the back contact solar cell body and parallel to the back surface. Alternatively, the width of the edge electrode pad 113 is in a direction perpendicular to the extending direction of the middle portion of the edge bus line 112. The middle portion of the edge bus line 112 is a portion of the edge bus line 112 except for two end portions. In the case where the edge bus line 112 is a straight line, the extending direction of the middle portion of the edge bus line 112 and the extending direction of the entire edge bus line 112 are parallel. For the case where the edge busbar line 112 is a straight line + an arc line, the extending direction of the middle portion of the edge busbar line 112 is: the edge bus line 112 extends along the direction except for both end portions. As shown in fig. 1-5, the edge bus line 112 is a straight line, and the extending direction of the middle portion of the edge bus line 112 is parallel to the extending direction of the entire edge bus line 112, e.g., parallel to the direction of the dotted line L in fig. 1. It should be noted that, hereinafter, the extending direction of the middle portion of the edge bus line 112 is defined as such.

The inventor finds that the prior art back contact solar cell is easy to crack in the process of forming a cell module, and particularly the edge of the back contact solar cell is easy to crack mainly due to two aspects: one is that the electrode disk near the edge is too close to the edge, resulting in stress being concentrated on the edge of the cell body by the conductive interconnect or lamination during the formation of the cell assembly, making the edge of the cell body prone to cracking. Secondly, the electrode disc close to the edge is arranged on the bus bar line of the edge, and the bus bar line of the edge has a certain height, so that the electrode disc close to the edge has a larger height difference with the surrounding electrode area, and in the process of forming the battery assembly, the conductive interconnection or lamination concentrates the stress on the edge of the battery body, so that the edge of the battery body is easy to break.

Referring to fig. 1, fig. 2, fig. 3, fig. 4, and fig. 5, in the embodiment of the present invention, in the edge electrode 11, each edge electrode 11 further includes: and an auxiliary gate line 114, the auxiliary gate line 114 connecting the edge bus gate line 112 and the edge electrode pad 113. The auxiliary gate lines 114 also function to collect carriers of the back contact solar cell body and transfer the carriers to the edge electrode pad 113. The edge electrode disk 113 is not arranged on the edge busbar line 112, meanwhile, the edge electrode disk 113 and the edge busbar line 112 are provided with a first interval, the edge electrode disk 113 is positioned on one side of the edge busbar line 112 far away from the corresponding position, the edge electrode disk 113 is the position of the subsequent battery assembly conductive interconnection, namely, a larger distance is reserved between the edge electrode disk 113 and the edge, and further, in the process of forming the battery assembly, the positions of the conductive interconnection between the back contact solar cells are also provided with a larger distance from the edge of the back surface of the battery body, so that stress concentration on the edge of the battery body can be avoided no matter the conductive interconnection or lamination is carried out, the probability of breakage of the back contact solar cells is reduced, and particularly, the probability of breakage of the area near the edge in the back contact solar cells is reduced. Meanwhile, in the edge electrode 11: the edge electrode disk 113 and the edge busbar line 112 have a first interval therebetween, so that the edge electrode disk 113 is substantially flush with the surrounding electrode area, and has almost no height difference or very small height difference, which is beneficial to reducing stress during lamination or conductive interconnection, and can reduce the probability of cracking of the back contact solar cell, especially the probability of cracking of the area near the edge in the back contact solar cell.

In fig. 4 and 5, 2 are conductive interconnects, and adjacent back contact solar cells are electrically connected through the conductive interconnects 2. The conductive interconnection may be a solder ribbon, a conductive interconnection board, or the like, and is not particularly limited in the embodiment of the present invention. Fig. 4 may be a schematic diagram of a cell string corresponding to the two back contact solar cells shown in fig. 1. Fig. 5 may be a schematic diagram of a cell string corresponding to the two back contact solar cells shown in fig. 3. The edge of the back contact solar cell body may be in contact with: the series direction of adjacent back contact solar cells in the cell string has at least parallel segments. The difference between fig. 1 and 3 is that the total number of bus bar lines in fig. 1 is an odd number, and the total number of bus bar lines in fig. 3 is an even number. As shown in fig. 4 and 5, in the case where the total number of bus bars is an odd number, the back contact solar cell may not need to be rotated in the process of forming the back contact solar cell string. In the case where the total number of bus bars is an even number, in the process of forming the back contact solar cell string, one back contact solar cell of every two back contact solar cells needs to be rotated by 180 °.

It should be noted that, the edge electrode pad 113 and the edge bus bar line 112 have a first interval, which can be understood as follows: the edge electrode pad 113 and the edge bus line 112 corresponding in position have a first interval. The positional correspondence here can be understood as: the edge electrode pad 113 and the edge bus bar line 112 in the same edge electrode 11 correspond to each other in position. For example, in fig. 1, 2, 3, 4, and 5, the edge electrode pad 113 and the edge bus line 112 in the leftmost edge electrode 11 correspond to each other in position, and the edge electrode pad 113 and the edge bus line 112 in the rightmost edge electrode 11 correspond to each other in position.

Optionally, as shown in fig. 1, fig. 2, fig. 3, fig. 4, and fig. 5, a plurality of edge electrode pads 113 are intermittently distributed in an extending direction parallel to the middle portion of the edge bus line 112. In the extending direction that is on a parallel with the middle part of border busbar line 112, the area of electrode has been reduced, the cost is reduced, has reduced the shading at the back moreover, simultaneously for the electric current between border electrode disc 113 and the border busbar line 112 can effectual closely collect, is favorable to promoting the generating efficiency.

Optionally, as shown in fig. 1, fig. 2, fig. 3, fig. 4, and fig. 5, in an extending direction parallel to the middle portion of the edge busbar line 112, the plurality of intermittently distributed edge electrode pads 113 are collinear, where collinear means that each of the plurality of edge electrode pads 113 is at least partially collinear. In the extending direction parallel to the middle part of the edge busbar line 112, the edge electrode pads 113 distributed discontinuously are collinear, so that the fault tolerance rate of production can be improved, the setting process of the edge electrode pads 113 is simple, the conductive interconnection or electric connection process is simple, the production cost can be reduced, and the production of non-standard devices can be avoided.

Optionally, the line width of the auxiliary gate line 114 is greater than the line width of the edge power collection gate line 111, and the direction of the line width of the edge power collection gate line 111 is perpendicular to the extending direction of the edge power collection gate line 111 and is parallel to the back surface. One end of the auxiliary grid line 114 is electrically connected with the edge bus grid line 112, the other end is electrically connected with the edge electrode pad 113, the edge bus grid line 112 leads current to the edge electrode pad 113 through the auxiliary grid line 114 which is electrically connected with the edge bus grid line and the edge electrode pad 113, the line width of the auxiliary grid line 114 is wide, and the transmission resistance between the edge bus grid line 112 and the edge electrode pad 113 can be reduced.

Alternatively, as shown in fig. 2, in the edge electrode 11: the first interval d5 is greater than or equal to 0.1mm, the distance between the edge electrode disc 113 and the edge is larger, and further, in the process of forming the cell module, the positions of the conductive interconnections between the back contact solar cells are further away from the edge of the back surface of the cell body, and stress concentration on the edge of the cell body can be avoided regardless of the conductive interconnections or lamination, so that the probability of cracking of the back contact solar cell is reduced, and particularly the probability of cracking of the area near the edge in the back contact solar cell is reduced. Meanwhile, in the edge electrode 11: the edge electrode disk 113 is arranged at one end close to the edge busbar line 112, and the interval between the edge electrode disk 113 and the end of the edge busbar line 112 close to the edge electrode disk 113 is larger, so that the edge electrode disk 113 is basically flush with the surrounding electrode area, almost no height difference or small height difference exists, stress in the lamination or conductive interconnection process is reduced, the probability of cracking of the back contact solar cell can be reduced, and particularly the probability of cracking of the area near the edge in the back contact solar cell is reduced.

Alternatively, as shown in fig. 2, in the edge electrode 11: the first interval d5 is greater than or equal to 0.2mm, the distance between the edge electrode disc 113 and the edge is larger, and therefore, in the process of forming the cell module, the positions of the conductive interconnections between the back contact solar cells are further away from the edge of the back surface of the cell body, and stress concentration on the edge of the cell body can be avoided regardless of the conductive interconnections or lamination, so that the probability of cracking of the back contact solar cell is reduced, and particularly the probability of cracking of the area near the edge in the back contact solar cell is reduced. Meanwhile, in the edge electrode 11: the edge electrode disk 113 is arranged at one end close to the edge busbar line 112, and the interval between the edge electrode disk 113 and the end of the edge busbar line 112 close to the edge electrode disk 113 is larger, so that the edge electrode disk 113 is basically flush with the surrounding electrode area, almost no height difference or small height difference exists, stress in the lamination or conductive interconnection process is reduced, the probability of cracking of the back contact solar cell can be reduced, and particularly the probability of cracking of the area near the edge in the back contact solar cell is reduced.

Optionally, as shown in fig. 1, fig. 2, fig. 3, fig. 4, and fig. 5, the electrode structure further includes an immediately adjacent electrode 12 adjacent to and spaced apart from the edge electrode 11, such as the electrode adjacent to the left edge electrode 11 in fig. 1, fig. 2, fig. 3, fig. 4, and fig. 5, that is, the immediately adjacent electrode 12 adjacent to the left edge electrode 11. The immediate-proximity electrode 12 and the edge electrode 11 are used to collect different types of carriers, respectively. For example, the edge electrode 11 is used to collect electron carriers, and the immediate vicinity electrode 12 is used to collect hole carriers. The proximate electrode 12 may include: adjacent collector grid lines 121, adjacent bus grid lines 122 that intersect adjacent collector grid lines 121, and adjacent electrode pads 123 disposed on adjacent bus grid lines 122. Edge electrode disk 113 of edge electrode 11, and immediately adjacent electrode 12: the adjacent electrode pads 123 adjacent to the edge electrode pad 113 in the extending direction perpendicular to the middle of the edge bus bar line 112 are collinear, that is, the edge electrode pad 113 adjacent to the edge electrode pad 123 in the left-right direction in the above-mentioned figure and the adjacent electrode pads 123 are collinear, the arrangement process of the edge electrode pad 113 and the adjacent electrode pads 123 is simple, the fault tolerance rate of production can be improved, the conductive interconnection or electrical connection process is simple, the production cost can be reduced, and the generation of non-standard devices can be avoided. Here, the collinear means that: the edge electrode pad 113 and the adjacent electrode pad 123 are at least partially collinear in an extending direction perpendicular to the middle of the edge bus line 112.

Fig. 6 is a partial schematic structural enlargement of an electrode structure of a second back contact solar cell in an embodiment of the present invention. Fig. 7 is a partial schematic structural enlargement of an electrode structure of a third back contact solar cell in an embodiment of the present invention. Fig. 8 is a schematic partial structure enlargement of an electrode structure of a fourth back contact solar cell in an embodiment of the present invention. The next adjacent electrode 12 as in fig. 6, 7, 8 is the electrode adjacent to the left edge electrode 11.

The first direction is perpendicular to the extending direction of the middle portion of the edge bus line 112. For example, referring to fig. 1-8, the first direction may be a left-right direction. It should be noted that the first direction mentioned throughout is the definition.

Optionally, in the adjacent electrode 12, in the extending direction of the middle part of the edge bus bar line 112, at least one adjacent bus bar line 121 adjacent to the end part of the edge electrode disk 113: at an end proximate the bus bar line 122 remote from where it intersects, there is a bent section 1211 that bends and extends into the first space. The size and the like of the bent section are not particularly limited. Specifically, the inventors found that: the arrangement position or the first interval of the edge electrode pad 113 occupies the arrangement space of the adjacent collector grid line 121 in the adjacent electrode 12, so that the extension length of the adjacent collector grid line 121 in the adjacent electrode 12 is shortened, and the collection of carriers corresponding to the adjacent collector grid line 121 in the adjacent electrode 12 is affected, which may reduce the electrical performance of the back contact solar cell. Therefore, in the present invention, in the next-to-electrode 12, in the extending direction of the middle portion of the edge bus bar line 112, at least one next-to-collector bar line 121 at the end portion of the next-to-edge electrode disk 113: the end far away from the intersecting end close to the busbar line 122 is provided with a bent section 1211 bent and extending into the first interval, the bent section 1211 is used for collecting carriers corresponding to the busbar line 121 in the close-proximity electrode, which is equivalent to make up for the arrangement position or the first interval of the edge electrode disk 113 through the bent section 1211, and the influence on the collection of the carriers corresponding to the busbar line 121 in the close-proximity electrode is further substantially avoided, so that the optical performance of the back contact solar cell is basically not influenced. Meanwhile, the bent section 1211 is disposed to sufficiently use a space corresponding to the first interval. Moreover, only in the adjacent electrodes 12, in the extending direction of the middle part of the edge busbar line 112, at least one adjacent busbar line 121 adjacent to the end part of the edge electrode disk 113 is formed with a bent section 1211, and no bent section is formed on the other adjacent busbar line 121 adjacent to the electrode 12, the area spanned by the bent section 1211 is small, the transmission loss on the bent section 1211 is small, and the improvement of the electrical performance of the back contact solar cell is facilitated.

More specifically, for example, the edge electrode 11 is used to collect electron carriers, the adjacent electrode is used to collect hole carriers, and the first space or the arrangement position of the edge electrode pad 113 interrupts the adjacent collector grid line 121 adjacent to the electrode 12, so that the hole carrier collection area adjacent to the electrode 12 is reduced, and the electrical performance is reduced. The utility model discloses in, in next-door neighbour electrode 12, on the extending direction at border busbar line 112's middle part, at least one next-door neighbour collection busbar line 121 of this border electrode disc 113 tip of next-door neighbour: the end far away from the intersecting end close to the bus bar line 122 is provided with a bent section 1211 bent and extending into the first interval, and further, the bent section close to the bus bar line 121 close to the electrode is provided to collect hole carriers along the bus bar line 111 in the first interval region, so that the problem of reduction of hole carrier collection caused by reduction of hole collection area of the close electrode is solved. Moreover, only in the adjacent electrodes 12, in the extending direction of the middle part of the edge busbar line 112, at least one adjacent busbar line 121 adjacent to the end part of the edge electrode disk 113 is formed with a bent section 1211, the area spanned by the bent section 1211 is small, the transmission loss on the bent section 1211 is small, and the improvement of the electrical performance of the back contact solar cell is facilitated.

For example, as shown in fig. 6, 7, and 8, the edge electrode pad 113 or the first space on the left side occupies the space for disposing the left end of the adjacent collector grid line 121 adjacent to the edge electrode pad 113 in the left-right direction, relative to the other adjacent collector grid lines in the adjacent electrodes 12, which results in that the extension length of the adjacent collector grid line 121 adjacent to the edge electrode pad 113 in the left-right direction in the adjacent electrodes 12 is shortened, so that the collection of carriers corresponding to the adjacent collector grid line 121 in the adjacent electrodes 12 is affected. Then, the left end of the adjacent collector grid line 121 adjacent to the upper end of the edge electrode disk 113 in the adjacent electrode 12 in the vertical direction has a bent section 1211 bent and extending into the first space, the bent section 1211 is used for collecting the carrier corresponding to the adjacent collector grid line 121 in the adjacent electrode, and the bent section 1211 makes up for the edge electrode disk 113 or the first space to collect the carrier corresponding to the adjacent collector grid line 121 in the adjacent electrode occupying space, so that the power generation efficiency of the back contact solar cell is not reduced, and the space of the first space is fully utilized. Moreover, only in the adjacent electrodes 12, in the extending direction of the middle part of the edge busbar line 112, a bent section 1211 is formed on at least one adjacent busbar line 121 adjacent to the upper end part of the edge electrode disk 113, the area spanned by the bent section 1211 is small, the transmission loss on the bent section 1211 is small, and the improvement of the electrical performance of the back contact solar cell is facilitated.

For another example, as shown in fig. 6, 7, and 8, the edge electrode pad 113 or the first space on the left side occupies the installation space of the left end of the adjacent collector grid line 121 adjacent to the edge electrode pad 113 in the left-right direction, compared with other adjacent collector grid lines in the adjacent electrode 12, which results in that the extension length of the adjacent collector grid line 121 adjacent to the edge electrode pad 113 in the left-right direction in the adjacent electrode 12 is shortened, so that the collection of carriers corresponding to the adjacent collector grid line 121 in the adjacent electrode 12 is affected. Then, the left end of the adjacent collector grid line 121 adjacent to the lower end of the edge electrode disk 113 in the adjacent electrode 12 in the vertical direction has a bent section 1211 bent to extend into the first space, the bent section 1211 is used for collecting the carrier corresponding to the adjacent collector grid line 121 in the adjacent electrode, and the bent section 1211 makes up for that the edge electrode disk 113 or the first space collects the carrier corresponding to the adjacent collector grid line 121 in the adjacent electrode occupying space, so that the power generation efficiency of the back contact solar cell is not reduced, and the space of the first space is fully utilized. Moreover, only in the adjacent electrodes 12, in the extending direction of the middle part of the edge busbar line 112, at least one adjacent busbar line 121 adjacent to the lower end part of the edge electrode disk 113 is formed with a bent section 1211, the area spanned by the bent section 1211 is small, the transmission loss on the bent section 1211 is small, and the improvement of the electrical performance of the back contact solar cell is facilitated.

Optionally, the first spacing is greater than or equal to 0.5mm, and/or the length of the edge electrode disk 113 is greater than or equal to 0.5mm. In the adjacent electrodes 12, in the extending direction of the middle part of the edge busbar line 112, at least one end of the adjacent collector grid line 121, which is adjacent to the end part of the edge electrode disk 113 and is far away from the intersecting adjacent busbar line 122, has a bent section 1211 bent to extend into a first interval. The length direction of the edge electrode pad 113 is parallel to the extending direction of the middle portion of the edge bus line 112. The first interval is greater than or equal to 0.5mm, and/or the length of the edge electrode pad 113 is greater than or equal to 0.5mm, which may represent that the edge electrode pad 113 or the first interval occupies more space in the adjacent electrode 12 adjacent to the collector grid line 122, so that the extension length of the adjacent collector grid line 121 in the adjacent electrode 12 is interrupted to be shorter, and the carrier collection area of the adjacent electrode 12 becomes smaller. Then, of the immediately adjacent electrodes 12, at least one immediately adjacent collector grid line 121 that is immediately adjacent to the end of the edge electrode pad 113 in the extending direction of the middle of the edge bus grid line 112: the end far away from the intersecting end adjacent to the bus bar line 122 has a bent section 1211 bent to extend into the first space, where the bent section 1211 is used for collecting carriers corresponding to the collector bar line 121 in the adjacent electrode 12, which is equivalent to make up for the layout position or the first space of the edge electrode pad 113 through the bent section 1211, and affects the collection of carriers corresponding to the collector bar line 121 in the adjacent electrode 12, so that the optical performance of the back contact solar cell is not affected substantially. Meanwhile, the bent portion 1211 is disposed to fully utilize the space corresponding to the first interval. Moreover, only in the adjacent electrodes 12, in the extending direction of the middle part of the edge busbar line 112, at least one adjacent busbar line 121 adjacent to the end part of the edge electrode disk 113 is formed with a bent section 1211, the area spanned by the bent section 1211 is small, the transmission loss on the bent section 1211 is small, and the improvement of the electrical performance of the back contact solar cell is facilitated.

More specifically, for example, the edge electrode 11 is used to collect electron carriers, and the adjacent electrode is used to collect hole carriers. The first interval is greater than or equal to 0.5mm, and/or the length of the edge electrode pad 113 is greater than or equal to 0.5mm, which can characterize the edge electrode pad 113 or the first interval, occupy more setting space in the adjacent electrode 12 adjacent to the collector grid line 122, and interrupt the adjacent collector grid line 121 adjacent to the electrode 12 more seriously, so that the hole carrier collecting area adjacent to the electrode 12 is further reduced, and the electrical performance is reduced. The utility model discloses in, in next-door neighbour electrode 12, on the extending direction at border busbar line 112's middle part, at least one next-door neighbour collection busbar line 121 of next-door neighbour border electrode disc 113 tip: the end far away from the intersecting end adjacent to the bus bar line 122 is provided with a bent section 1211 bent to extend into the first interval, and further, the edge of the current collecting bar line 111 is provided in the first interval region to collect electron carriers, and the bent section adjacent to the current collecting bar line 121 is provided adjacent to the electrode to collect hole carriers, so that the problem that the hole carrier collection is reduced due to the reduction of the hole collection area of the adjacent electrode is solved. Moreover, only in the adjacent electrodes 12, in the extending direction of the middle part of the edge busbar line 112, at least one adjacent busbar line 121 adjacent to the end part of the edge electrode disk 113 is formed with a bent section 1211, the area spanned by the bent section 1211 is small, the transmission loss on the bent section 1211 is small, and the improvement of the electrical performance of the back contact solar cell is facilitated.

It should be noted that, the width of the edge electrode pad 113 is larger, and it is also possible to represent the edge electrode pad 113 or the first interval, occupy more setting space in the adjacent electrode 12 adjacent to the collector grid line 122, and interrupt the adjacent collector grid line 121 adjacent to the electrode 12 more seriously, so that the hole carrier collecting area adjacent to the electrode 12 is further reduced, and the electrical performance is reduced. In this case, of the immediately adjacent electrodes 12, at least one immediately adjacent collector gate line 121 immediately adjacent to the end of the edge electrode pad 113 in the extending direction of the middle portion of the edge bus gate line 112: at an end proximate the bus bar line 122 remote from where it intersects, there is a bent section 1211 that bends and extends into the first space. In the embodiment of the present invention, this is not particularly limited. The width direction of the edge electrode pad 113 is perpendicular to the extending direction of the middle portion of the edge bus line 112.

Optionally, as shown in fig. 6, 7 and 8, at least one of the end portions of the edge electrode pad 113 is further connected with a second grid line 115, and the second grid line 115 is used for collecting carriers that back contact the solar body and transmitting the collected carriers to the edge electrode pad 113. That is, the carriers collected by the second gate line 115 are directly collected by the edge electrode pad 113 without passing through the edge bus line 112. The setting mode of the collecting grid line is flexible and various. As shown in fig. 6, the second gate line 115 is connected to the upper, lower and right end portions of the edge electrode pad 113. In fig. 7 and 8, the upper, lower, left and right end portions of the edge electrode pad 113 are connected to a second gate line 115.

Optionally, a dotted line N in fig. 7 shows a direction of an extending length of the bent segment 1211, the extending length of the bent segment 1211 is greater than or equal to a half of the length of the edge electrode pad 113, and both the length direction of the edge electrode pad 113 and the extending length direction of the bent segment 1211 are parallel to the extending direction of the middle portion of the edge bus line 112. That is, the edge electrode pad 113 occupies a larger space of the adjacent collecting grid line 122 in the adjacent electrode 12, so that the extension size of the bending section 1211 is longer, and more carriers corresponding to the adjacent collecting grid line 121 in the adjacent electrode 12 can be collected, thereby substantially not affecting the optical performance of the back contact solar cell.

For example, in fig. 6 and 7, the extending length of the bent portion 1211 is greater than or equal to half of the length of the edge electrode pad 113. Other differences between fig. 6 and 7 are: the length of the edge electrode pad 113 in fig. 7 is larger, and further, the edge electrode pad 113 in fig. 7 occupies more space in the vertical direction, so that, in fig. 7, the extension length of the bending section 1121 is larger, and more carriers corresponding to the collector grid lines 121 in the immediate vicinity of the electrode can be collected, so that the optical performance of the back contact solar cell is not affected basically.

Optionally, referring to fig. 8, the line width d6 of the bending section 1211 is 20-300um. The line width d6 of the bending portion 1211 is perpendicular to the tangent line of the bending portion and parallel to the back surface. The line width d6 of the bent portion 1211 is within this range, and the manufacturing cost and the collection of current are well balanced. Preferably, the line width of the bent portion 1211 may be equal to the line width of the adjacent collector grid line 121, thereby facilitating the preparation of the bent portion 1211 at a lower cost.

Alternatively, the shape of the bent section 1211 is L-shaped or F-shaped, and the bent section 1211 having the above shape makes full use of a space on the back surface, is easy to manufacture, and achieves a good balance for collecting current. As shown in fig. 6, the bent section 1211 has an L-shape. As shown in fig. 7 and 8, the bent portion 1211 has an F-shape.

Optionally, referring to fig. 6, at least one of the adjacent collector grid lines 121: the end of the bus bar line 122 away from the end to which the bus bar line is electrically connected has a back hook 1212. Due to the arrangement position or the first interval of the edge electrode pad 113, the arrangement space of the adjacent collector grid line 121 in the adjacent vicinity of the electrode 12 is occupied, so that the extension length of the adjacent collector grid line 121 in the adjacent vicinity of the electrode 12 is shortened, the collection of carriers corresponding to the adjacent collector grid line 121 in the adjacent vicinity of the electrode 12 is affected, and the electrical performance of the back contact solar cell may be reduced. As the back hook 1212 has a larger contact area with the back surface of the back contact solar cell body than the straight segment, the back hook 1212 is used for collecting carriers corresponding to the collector grid line 121 in the adjacent electrode 12, which is equivalent to make up for the influence of the arrangement position of the edge electrode pad 113 and the first interval on the collection of carriers corresponding to the collector grid line 121 in the adjacent electrode through the back hook 1212, so that the optical performance of the back contact solar cell is not affected basically.

Fig. 9 shows a schematic structural diagram of an electrode structure of a third back contact solar cell in an embodiment of the present invention. Optionally, referring to fig. 9, in the edge bus line 112: the portion of the back face on the chamfer is an arc segment 1121, and the remainder is a straight segment 1122.

The width of the arc 1121 increases from a distance from the edge electrode pad 113 to a direction closer to the edge electrode pad 113. The line width of the arc segment 1121 is perpendicular to the tangent of the arc segment 1121 and is parallel to the back surface. The current passing through the arc segment 1121 increases in the direction from being far from the edge electrode disk 113 to being close to the edge electrode disk 113, and the line width of the arc segment 1121 increases in the direction from being far from the edge electrode disk 113 to being close to the edge electrode disk 113, so that the resistance of the arc segment 1121 decreases in the direction from being far from the edge electrode disk 113 to being close to the edge electrode disk 113, and the resistance loss can be reduced. As shown with reference to fig. 9, the line width of the arc segment 1121 increases in the direction indicated by the broken-line arrow Q.

Optionally, the line width of the arc segment 1121 gradually increases from a direction away from the edge electrode pad 113 to a direction close to the edge electrode pad 113, so as to better adapt to the passing gradually increased current. That is, the line width of the arc segment 1121 increases equally from the direction away from the edge electrode pad 113 toward the direction toward the edge electrode pad 113, or the slope of the increase in line width is equal.

Optionally, a line width of a portion of the arc segment 1121, which is closest to the edge electrode pad 113, is equal to a line width of the straight segment 1122, and the line width of the straight segment 1122 is perpendicular to the straight segment 122 and parallel to the back surface. And/or the line width of the portion farthest from the edge electrode pad 113 in the arc segment 1121 is equal to the line width of the edge power collection gate line 111, and the direction of the line width of the edge power collection gate line 111 is perpendicular to the edge power collection gate line and is parallel to the back surface. The line width of the arc segment 1121 is set to be easy to process, and the production cost is reduced.

Optionally, the line width of the portion closest to the edge electrode pad 113 in the arc segment 1121 may be: 50um-1000um. Further, the line width of the portion of the arc segment 1121 closest to the edge electrode pad 113 may be: 50um-500um, the linewidth setting of above-mentioned arc 1121 has easily processed, has reduced manufacturing cost.

Optionally, referring to fig. 1 to 8, the extending direction of the edge collecting grid line 111 is perpendicular to the extending direction of the middle portion of the edge collecting grid line 112, so that the transmission resistance and the current transmission path are excellent, and the power generation efficiency of the back contact solar cell can be improved.

Optionally, as shown in fig. 1, fig. 2, fig. 3, fig. 4, and fig. 5, the electrode structure on the back surface of the back contact solar cell body further includes: at least one middle electrode 13 disposed apart from the edge electrode 11, the middle electrode 13 being an electrode of all the electrodes except the edge electrode 11 and the adjacent electrode 12. Each of the middle electrodes 13 includes: a middle collector grid line 131, a middle bus grid line 132 electrically connected or intersecting the middle collector grid line 131, and a middle electrode pad 133 disposed on the middle bus grid line 132. The middle collector grid lines 131 are used to collect carriers of the back contact solar cell body. The middle bus bar line 132 is mainly used for collecting carriers on the middle bus bar line 131 and transmitting the collected carriers to the middle electrode pad 133. The middle bus bar line 132 and the edge bus bar line 112 are distributed in parallel. Referring to fig. 1, 2, 3, 4, and 5, for one back contact solar cell: all electrodes are interdigitated on the back surface, with adjacent electrodes of opposite polarity. The middle bus bar line 132 may have a linear or arc shape, and the middle bus bar line 131 may have a linear or arc shape. The shape of the middle electrode disk 133 may be rectangular, and the like, which is not specifically limited in the embodiment of the present invention.

The middle bus bar line adjacent to the edge bus bar line 112, i.e., immediately adjacent to the bus bar line 122, is described above. As shown in fig. 1, a distance d1 between the edge bus bar line 112 and the adjacent middle bus bar line is greater than a distance d2 between the adjacent middle bus bar lines 132. The direction of the distance d1 or d2 is perpendicular to the extending direction of the middle part of the edge busbar line 112, and is parallel to the back surface of the back contact solar cell body.

The middle electrode disk adjacent to the edge electrode disk 113 is the immediately adjacent electrode disk 123 as previously described. As shown in fig. 2, the distance d3 between the edge electrode pad 113 and the adjacent middle electrode pad is equal to the distance d4 between the adjacent middle electrode pads 133, so that the fault tolerance of production can be improved, production equipment can be shared, the production cost can be reduced, and the generation of non-standard devices can be avoided, and meanwhile, the stress is uniformly distributed in the back-contact solar cell, and the probability of cell rupture can be reduced.

Optionally, the utility model discloses in, the length that is located the border and converges the current collection grid line of the first region between grid line 112 and the adjacent middle part and converges between the grid line is m1, and the length that is located the second region between the adjacent middle part and converges the current collection grid line is m2, and wherein, the current collection grid line of first region is including being located border and converges grid line 112 and adjacent middle part and converge border and middle part current collection grid line between the grid line, and the current collection grid line of second region is including being located adjacent middle part and converging the middle part current collection grid line between the grid line. The relative sizes of m1 and m2 are not particularly limited. For example, m1 > m2 may be used in order to sufficiently collect carriers of the second region. M1= m2 is also possible. For example, in the case where the distance d1 between the edge bus line 112 and the adjacent middle bus line is greater than the distance d2 between the adjacent middle bus line 132, m1 > m2, so as to sufficiently collect carriers between the edge bus line 112 and the adjacent middle bus line. The directions of m1 and m2 may be perpendicular to the extending direction of the middle portion of the edge bus line 112.

Optionally, referring to fig. 6, 7, and 8, a portion of the second gate line 115 extending along the first direction is collinear with the middle current collecting gate line 131 adjacent to the first direction, so that in the process of manufacturing the second gate line 115 and the middle current collecting gate line 131, the process is simple, the production cost can be reduced, the fault tolerance of production can be improved, and the non-standard device can be avoided. The first direction is perpendicular to the extending direction of the middle portion of the edge bus line 112. Collinear here means that: the portion of the second grid line 115 extending along the first direction is at least partially collinear with the middle current collecting grid line 131 adjacent in the first direction.

Alternatively, referring to fig. 1 and 3, the plurality of edge electrode pads 113 and the plurality of middle electrode pads 133 are distributed in an interdigital array to form an electrode pad array. The electrode pad array is symmetrically distributed along a center line of the electrode pad array, which has at least a portion parallel to an extending direction of the middle portion of the edge busbar line 112. The symmetrical distribution here means that as long as the electrode disks have a partial overlap area with the electrode disks in the array at a symmetrical position on the other side of the center line. The electrode disk array is symmetrically distributed along the central line of the electrode disk array, so that the fault tolerance rate of production can be improved, the processing complexity is favorably reduced, the stress in the back-contact solar battery is uniformly distributed, and the probability of breakage can be reduced. Further, the electrode disk array can also be symmetrically distributed along another central line perpendicular to the extending direction of the middle part of the edge bus bar 112, so that the fault tolerance rate of production can be further improved, the processing complexity can be favorably reduced, the stress in the back-contact solar battery is more uniformly distributed, and the probability of breakage can be further reduced.

Optionally, the edge collecting grid line 111 is: the edge current collecting grid line of screen printing, or the edge current collecting grid line of electroplating, this is that this edge current collecting grid line 111 can adopt the screen printing preparation to obtain, also can adopt the electroplating preparation to obtain, and the preparation mode of edge current collecting grid line 111 is nimble various. The edge collecting grid line 111 is mature in screen printing preparation process, and production cost can be properly reduced by adopting electroplating preparation.

And/or, the auxiliary gate line 114 is: screen printed auxiliary grid lines, or electroplated auxiliary grid lines. That is to say, the auxiliary gate line 114 can be prepared by screen printing or electroplating, and the preparation method of the auxiliary gate line 114 is flexible and various. The auxiliary grid line 114 is mature in screen printing preparation process, and production cost can be properly reduced by adopting electroplating preparation.

And/or, the edge bus grid line 112 is: the edge busbar line of screen printing, or the edge busbar line of electroplating, that is to say, edge busbar line 112 can adopt the screen printing preparation to obtain, also can adopt the electroplating preparation to obtain, and the preparation mode of edge busbar line 112 is nimble various. The edge busbar line 112 is mature in screen printing preparation process, and production cost can be properly reduced by adopting electroplating preparation.

And/or, the edge electrode disk 113 is: screen printed edge electrode pads are well-established in process and facilitate conductive interconnection, such as soldering, during formation of the cell string.

Optionally, the edge collecting grid line 111 is: the screen-printed edge collector grid line, the auxiliary grid line 114 is: the auxiliary grid line of screen printing, border busbar line 112 do: the edge busbar line of screen printing, edge electrode panel 113 are: screen printed edge electrode disks. That is, the edge collector grid line 111, the auxiliary grid line 114, the edge collector grid line 112, and the edge electrode pad 113 are all prepared by screen printing, and the process is mature.

Or, the edge collecting grid line 111 is: the edge of the plated current collection grid line, the auxiliary grid line 114 is: the auxiliary grid line of electroplating, border busbar line 112 is: the edge busbar line of electroplating, edge electrode panel 113 is: screen printed edge electrode disks. That is, the edge collector grid lines 111, the auxiliary grid lines 114 and the edge collector grid lines 112 are all manufactured by electroplating, which is beneficial to reducing the production cost, the edge electrode pads 113 are manufactured by screen printing, the process is mature, and the conductive interconnection in the process of forming the battery strings is convenient, such as being beneficial to welding.

The embodiment of the utility model provides a still provide a back of body contact solar cell's electrode half tone, this electrode half tone is used for printing arbitrary foretell back of body contact solar cell's electrode structure, and this electrode half tone has the same or similar beneficial effect with foretell electrode structure, avoids the repetition, and here is no longer repeated.

It should be noted that the electrode screen may be an integral screen, or the electrode screen may be composed of a plurality of sub-screens. If the electrode screen is an integral screen, the integral screen printing obtains any of the electrode structures of the back contact solar cell. If the electrode screen is composed of a plurality of sub-screen printing plates, each sub-screen printing plate is respectively used for printing part of the electrode structure of any back contact solar cell, and all sub-screen printing plates are combined to print the electrode structure of any back contact solar cell. In the embodiment of the present invention, this is not particularly limited.

For example, the electrode screen may comprise: the first sub-screen printing plate, the second sub-screen printing plate, the third sub-screen printing plate, the fourth sub-screen printing plate and the fifth sub-screen printing plate. The first sub-screen is used for printing the edge electrode disc and/or is close to the electrode disc and/or is used for printing the edge bus grid line, the second sub-screen is used for printing the edge bus grid line and/or is close to the bus grid line and/or is used for printing the edge bus grid line, the middle bus grid line and the third sub-screen is used for printing the edge bus grid line and/or is close to the bus grid line and/or is used for printing the auxiliary grid line, and the fifth sub-screen is used for printing the second grid line.

The embodiment of the utility model provides a back contact solar cell is still provided, this back contact solar cell includes the electrode structure of arbitrary aforementioned back contact solar cell, and this back contact solar cell has the same or similar beneficial effect with aforementioned electrode structure, in order to avoid repetition, and here is no longer repeated.

Optionally, the back contact solar cell includes: a whole cell or a sliced cell. The cutting line on the back of the sliced battery body is perpendicular to the extending direction of the middle part of the edge busbar line. As shown in fig. 1, 3, and 9, the back contact solar cell is a monolithic cell. Fig. 10 shows a schematic structural diagram of a fourth back contact solar cell in an embodiment of the present invention. Referring to fig. 10, the back contact solar cell is a diced cell, and the dicing lines on the back surface of the diced cell body are parallel to the left-right direction. It should be noted that the tandem process of the diced cell and the whole cell is similar in the process of forming the back contact solar cell string.

The embodiment of the utility model provides a still provide a battery pack, this battery pack includes the arbitrary aforementioned back contact solar cell of a plurality of. The cell assembly has the same or similar beneficial effects with any of the back contact solar cells, and the details are not repeated herein in order to avoid repetition.

The embodiment of the utility model provides a still provide a production method of back of body contact solar cell's electrode structure, this production method includes following step: at least two groups of electrodes with opposite polarities are arranged on the back surface of the back contact solar cell main body at intervals; the two sets of electrodes with opposite polarities comprise: forming at least one edge electrode; the edge electrode includes: the edge collector grid lines are used for collecting carriers of the back contact solar cell body; an edge busbar extending along an edge of the back contact solar cell body; the edge busbar grid line is intersected with the edge busbar grid line; the edge electrode disc is positioned on one side, far away from the edge, of the edge busbar line and has a first interval with the edge busbar line; and the auxiliary grid line is used for connecting the edge bus grid line and the edge electrode disk.

The method for manufacturing the electrode structure of the back contact solar cell has the same or similar beneficial effects as any one of the electrode structures of the back contact solar cell, and is not repeated herein for avoiding repetition.

Optionally, the edge electrode disk 113 is prepared first, and then the edge power collecting gate line 111 is prepared, so that the edge power collecting gate line 111 can be prevented from being flattened in the process of preparing the edge electrode disk 113. The edge bus bar line 112 may be fabricated at the same time as the edge bus bar line 111, or the edge bus bar line 112 may be fabricated at the same time as the edge electrode pad 113, or the edge bus bar line 112 may be fabricated separately. In the embodiment of the present invention, this is not particularly limited.

Optionally, the adjacent collector grid line 121, the adjacent collector grid line 122, and the adjacent electrode pad 123 in the adjacent electrode 12, and the middle collector grid line 131, the middle collector grid line 132, and the middle electrode pad 133 in the middle electrode 13 may correspond to the preparation method of the edge collector grid line 111, the edge collector grid line 112, and the edge electrode pad 113 in the reference edge electrode 11, and are not described herein again to avoid repetition.

In the electrode structure of the back contact solar cell, the electrode screen of the back contact solar cell, the cell module, and the method for producing the electrode structure of the back contact solar cell, corresponding portions between the five can be referred to each other.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one of 8230, and" comprising 8230does not exclude the presence of additional like elements in a process, method, article, or apparatus comprising the element.

While the embodiments of the present invention have been described with reference to the accompanying drawings, the present invention is not limited to the above-described embodiments, which are merely illustrative and not restrictive, and many modifications may be made by one skilled in the art without departing from the spirit and scope of the present invention as defined in the appended claims.

Claims

1. An electrode structure of a back contact solar cell is characterized in that,

the edge electrode includes:

the plurality of edge collecting grid lines are used for collecting carriers of the back contact solar cell body;

an edge busbar extending along an edge of the back contact solar cell body; the edge busbar grid line is intersected with the edge busbar grid line;

and (c) a second step of,

2. The electrode structure of a back contact solar cell of claim 1, wherein a plurality of said edge electrode pads are intermittently distributed in an extending direction parallel to a middle portion of said edge busbar line.

3. The electrode structure of a back contact solar cell according to claim 2,

and in the extending direction parallel to the middle part of the edge busbar line, a plurality of the edge electrode discs which are distributed discontinuously are collinear.

4. The electrode structure of a back contact solar cell of claim 1, further comprising: a proximate electrode adjacent to and spaced apart from the edge electrode;

the proximate electrode includes: the adjacent current collecting grid line is intersected with the adjacent current collecting grid line;

5. The electrode structure of a back contact solar cell according to claim 4, wherein the first spacing is greater than or equal to 0.5mm, and/or the length of the edge electrode pad is greater than or equal to 0.5mm; the length direction of the edge electrode disc is parallel to the extending direction of the middle part of the edge busbar line.

6. The electrode structure of a back contact solar cell of claim 4, wherein a second grid line is further connected to an end of the edge electrode pad.

7. The electrode structure of a back contact solar cell according to any one of claims 4-6, wherein the extension length of the bending section is greater than or equal to half of the length of the edge electrode disk; the length direction of the edge electrode disc and the extension length direction of the bending section are parallel to the extension direction of the middle part of the edge busbar line.

8. The electrode structure of a back contact solar cell according to any of claims 4-6, wherein the line width of the bending section is 20-300um.

9. The electrode structure of a back contact solar cell according to any of claims 4-6, wherein the shape of the bent segments is: l-form or F-form.

10. The electrode structure of any one of claims 1-6, wherein the width of the auxiliary grid line is greater than the width of the edge collector grid line.

11. The electrode structure of a back contact solar cell according to any of claims 1-4, wherein the first spacing is greater than or equal to 0.1mm.

12. The electrode structure of a back contact solar cell of claim 11, wherein the first spacing is greater than or equal to 0.2mm.

13. The electrode structure of a back contact solar cell of claim 4, wherein said immediately adjacent electrodes further comprise: an adjacent electrode disk disposed on the adjacent busbar line; and in the direction vertical to the extending direction of the middle part of the edge busbar line, the adjacent electrode disk and the edge electrode disk are collinear.

14. The electrode structure of a back contact solar cell of any of claims 1-6, wherein in the edge busbar line: the chamfer part positioned on the back is an arc line segment, and the rest part is a straight line segment;

15. The electrode structure of a back contact solar cell of claim 14, wherein the arc segments have a line width that gradually increases from a distance from the edge electrode disk to a distance from the edge electrode disk.

16. The electrode structure of a back contact solar cell according to claim 14,

the line width of the part, closest to the edge electrode disc, of the arc line segment is equal to the line width of the straight line segment;

17. The electrode structure of a back contact solar cell of any of claims 1-6, wherein the direction of extension of the edge collector grid lines and the direction of extension of the middle portion of the edge busbar lines are perpendicular to each other.

18. The electrode structure of a back contact solar cell according to claim 1,

the electrode structure further includes: with at least one middle part electrode that border electrode interval set up, every middle part electrode all includes: the middle part collector grid line, the middle part collector grid line intersected with the middle part collector grid line and the middle part electrode disc arranged on the middle part collector grid line; the middle bus grid line and the edge bus grid line are distributed in parallel;

19. The electrode structure of a back contact solar cell of claim 18,

the end part of the edge electrode disc is also connected with a second grid line; the part of the second grid line extending along the first direction is collinear with the middle current collecting grid line adjacent to the first direction; the first direction is perpendicular to the extending direction of the middle of the edge busbar line.

20. The electrode structure of a back contact solar cell of claim 18, wherein a plurality of said edge electrode pads and a plurality of said middle electrode pads are distributed in an interdigitated array to form an array of electrode pads;

the electrode disk array is symmetrically distributed along the central line of the electrode disk array; the center line has at least a portion parallel to an extending direction of a middle portion of the edge bus line.

21. The electrode structure of a back contact solar cell of any of claims 1-6, wherein the edge collector grid line is: the edge of the silk-screen printing collects the grid line, or the edge of the electric plating collects the grid line;

and/or the edge electrode disk is: screen printed edge electrode pads.

22. The electrode structure of a back contact solar cell of claim 21, wherein the edge collector grid line is: the edge of the silk-screen printing collects the grid line, the said auxiliary grid line is: auxiliary grid line of screen printing, the border busbar line is: the border of screen printing converges the grid line, the border electrode dish is: a screen printed edge electrode disk;

23. An electrode screen of a back contact solar cell is characterized in that: the electrode screen of the back contact solar cell is used for printing the electrode structure of the back contact solar cell as claimed in any one of claims 1 to 22.

24. A back contact solar cell comprising the electrode structure of the back contact solar cell of any one of claims 1-22.

25. The back contact solar cell of claim 24, wherein the back contact solar cell comprises: a whole cell or a sliced cell;

and the cutting line on the back surface of the sliced battery body is vertical to the extending direction of the middle part of the edge busbar line.

26. A battery assembly, comprising: a plurality of back contact solar cells as claimed in claim 24 or 25;

each back contact solar cell is electrically connected at least through the edge electrode pad.