A main grid-free solar cell and a battery assembly

Abstract

The utility model relates to a main grid-free solar cell and a battery assembly, wherein auxiliary grid lines are arranged at intervals on the surface of the battery cell, and the auxiliary grid lines include a continuous auxiliary grid line extending continuously in the horizontal direction and a segmented auxiliary grid line arranged in a segmented manner in the horizontal direction, and the endpoints of two adjacent segmented auxiliary grid lines are respectively connected to auxiliary auxiliary grid lines, and the upper and lower ends of the auxiliary auxiliary grid line in the vertical direction are respectively connected to the two upper and lower adjacent continuous auxiliary grid lines; the auxiliary auxiliary grid line and the two upper and lower adjacent continuous auxiliary grid lines form a glue-dispensing area coated with insulating glue, and a welding strip in contact with the continuous auxiliary grid line is laid on the insulating glue. The utility model can effectively prevent the local circuit breakage caused by the deviation of the insulating glue during glue dispensing by forming a glue-dispensing area with the auxiliary auxiliary grid line and the continuous auxiliary grid line at the insulating glue laying position, thereby improving the quality rate and power output of the solar cell.

Description

Technical Field

[0001] The utility model relates to the technical field of solar cells, in particular to a main grid-free solar cell and a battery assembly. Background Art

[0002] As the core component of solar power generation, solar cells are the basis for reducing costs and improving power generation efficiency. The grid lines in solar cells collect and converge current, but they will form a certain shielding area, thus affecting the efficiency of the cell.

[0003] In order to improve the conversion efficiency of solar cells, busbar-less technology came into being. The essence of busbar-less technology is to improve efficiency and reduce costs by optimizing battery electrodes, welding rods and components. It has the advantages of reducing battery costs, reducing shading area and improving the battery's ability to collect current.

[0004] The busbar-free technology has overturned the traditional welding process. The key to realizing this process is to use insulating glue to fix the welding strip on the battery cell, and then realize alloying during the component lamination process. However, this technology requires high precision in the dispensing of insulating glue. Once the dispensing position is offset, it is very easy to cause the battery cell to have a current circuit break in this area, resulting in current loss. Summary of the invention

[0005] The technical problem to be solved by the utility model is: in order to overcome the deficiencies in the prior art, the utility model provides a main grid-free solar cell and a battery assembly to ensure that the glue dispensing position is accurate and prevent the battery cell from short-circuiting in the glue dispensing area.

[0006] The utility model adopts the following technical scheme to solve the technical problem: a main grid-free solar cell, comprising a cell sheet, wherein mutually parallel auxiliary grid lines are arranged at intervals on the surface of the cell sheet, the auxiliary grid lines comprising a continuous auxiliary grid line continuously extending in the horizontal direction, and a segmented auxiliary grid line arranged in the horizontal direction in segments, the segmented auxiliary grid line being arranged between two continuous auxiliary grid lines in the vertical direction in an interval-like manner, the end points of two adjacent segmented auxiliary grid lines are respectively connected with auxiliary auxiliary grid lines, and the upper and lower ends of the auxiliary auxiliary grid line in the vertical direction are respectively connected with the two upper and lower adjacent continuous auxiliary grid lines; the auxiliary auxiliary grid line and the two upper and lower adjacent continuous auxiliary grid lines form a glue spotting area, the glue spotting area is coated with insulating glue, and a welding strip in contact with the continuous auxiliary grid line is laid on the insulating glue.

[0007] In order to increase the contact area between the welding strip and the auxiliary grid line and enhance the bonding force between the welding strip and the auxiliary grid line, the continuous auxiliary grid line is provided with an auxiliary grid reinforcement section integrally formed with the continuous auxiliary grid line. The auxiliary grid reinforcement sections are spaced apart in the vertical direction and are located on the same straight line as the glue dispensing area.

[0008] The glue dispensing area is in the shape of a rhombus, an arc or a regular hexagon, so as to reserve as large a coating space as possible for the insulating glue.

[0009] Furthermore, the segmented secondary grid line includes two edge segments and at least one middle segment.

[0010] To prevent partial area disconnection caused by grid breakage during processing, the endpoints of the two adjacent segmented secondary grid lines are respectively connected with two auxiliary secondary grid lines connected to the two upper and lower adjacent continuous secondary grid lines.

[0011] In order to prevent the continuous secondary grid lines from being covered by insulating glue and causing partial circuit breakage, the two ends of the auxiliary secondary grid lines are respectively connected to at least two upper and lower adjacent continuous secondary grid lines.

[0012] A busbar-free solar cell assembly comprises the above-mentioned busbar-free solar cell.

[0013] The beneficial effects of the utility model are as follows: the utility model connects the segmented secondary grid lines to the continuous secondary grid lines by setting auxiliary secondary grid lines at the end points of the segmented secondary grid lines to prevent the short circuit caused by the segmented secondary grid lines; and the glue spotting area surrounded by the auxiliary secondary grid lines and the continuous secondary grid lines at the insulating glue laying position can effectively prevent the local short circuit caused by the deviation of the insulating glue during glue spotting, thereby improving the power output of the solar cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The utility model is further described below in conjunction with the accompanying drawings and implementation modes.

[0015] Figure 1 It is a schematic diagram of the planar structure of the solar cell of the utility model.

[0016] Figure 2 It is a schematic diagram of the cross-sectional structure of the solar cell assembly of the utility model.

[0017] Figure 3 yes Figure 1 A schematic diagram of the local enlarged structure of the dispensing area shown in the middle.

[0018] Figure 4 This is a schematic diagram of the enhanced connection of the auxiliary secondary grid lines described in the utility model.

[0019] Figure 5 This is a schematic diagram of the enhanced connection of the auxiliary secondary grid lines described in the utility model.

[0020] Figure 6 It is a schematic diagram of the shape structure of the glue dispensing area of ​​the utility model.

[0021] Figure 7It is a schematic diagram of the shape structure of the glue dispensing area of ​​the utility model.

[0022] Figure 8 It is a schematic diagram of the shape structure of the glue dispensing area of ​​the utility model.

[0023] In the figure: 1. Battery cell, 2. Continuous auxiliary grid line, 3. Segmented auxiliary grid line, 3-1. Edge segment, 3-2. Middle segment, 4. Auxiliary auxiliary grid line, 5. Glue dispensing area, 6. Insulating glue, 7. Soldering strip, 8. Auxiliary grid reinforcement segment 9. Front glass, 10. Front package, 11. Back package, 12. Back glass. DETAILED DESCRIPTION

[0024] Now the utility model is further described in detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, which only illustrate the basic structure of the utility model in a schematic manner, and therefore only show the components related to the utility model.

[0025] like Figure 1 , Figure 3 A busbar-free solar cell is shown, comprising a cell 1, wherein parallel secondary grid lines are arranged at intervals on the surface of the cell 1, wherein the secondary grid lines comprise a continuous secondary grid line 2, a segmented secondary grid line 3 and an auxiliary secondary grid line 4, wherein the continuous secondary grid line 2 extends continuously in the horizontal direction, and the segmented secondary grid line 3 is arranged at segmented intervals in the horizontal direction, and the segmented secondary grid line 3 consists of two edge segments 3-1 and three middle segments 3-2.

[0026] Auxiliary auxiliary grid lines 4 are provided between the edge segment 3-1 and the middle segment 3-2 of the segmented auxiliary grid line 3, and between the middle segments 3-2 and the middle segments 3-2. The middle of the auxiliary auxiliary grid line 4 is connected to the end points of the edge segment 3-1 and the middle segment 3-2. The upper and lower ends of the auxiliary auxiliary grid line 4 in the vertical direction are respectively connected to the two upper and lower adjacent continuous auxiliary grid lines 2, thereby connecting the segmented auxiliary grid line 3 with the upper and lower adjacent continuous auxiliary grid lines 2.

[0027] After being connected in this way, the two auxiliary secondary grid lines 4 between the edge segment 3-1 and the middle segment 3-2 and the two upper and lower adjacent continuous secondary grid lines 2 form a glue spotting area 5, and the two auxiliary secondary grid lines 4 between the two middle segments 3-2 and the two upper and lower adjacent continuous secondary grid lines 2 also form a glue spotting area 5. The glue spotting areas 5 formed by the above two structures are in the same straight line in their respective horizontal and vertical directions.

[0028] An insulating glue 6 is coated at the center of the glue-dispensing area 5 , and a welding strip 7 in contact with the continuous secondary grid line 2 is laid on the insulating glue 6 .

[0029] The insulating glue 6 is UV glue, which is composed of resin, monomer, photoinitiator and other auxiliary materials. The photoinitiator in the UV glue forms free radicals under the excitation of ultraviolet light, and the active free radicals initiate the polymerization of the monomers, thereby curing. The insulating glue 6 can be applied to the center of the glue dispensing area 5 by screen printing, multi-head glue dispensing or sputtering glue dispensing.

[0030] Since the insulating glue 6 is easily applied to the auxiliary grid line, an insulating layer is easily formed between the auxiliary grid line and the welding strip 7 at this position, resulting in that the carriers collected by the auxiliary grid line at this position cannot be transmitted to the welding strip 7, resulting in current loss. After setting the glue dispensing area 5, there is a larger range for the laying of the insulating glue 6, and it does not affect the continuous path of the surrounding auxiliary grid lines, which can reduce the laying accuracy requirements of the insulating glue 6 and improve the output of the solar cell.

[0031] The carriers generated by the photovoltaic effect of the solar cell are collected and transmitted by the auxiliary grid lines. At the position of the continuous auxiliary grid line 2, the carriers are directly transmitted to the welding strip 7 by the continuous auxiliary grid line 2. At the break of the segmented auxiliary grid line 3, the carriers are transmitted to the continuous auxiliary grid line 2 through the auxiliary auxiliary grid line 4, and then transmitted out through the welding strip 7 connected to the continuous auxiliary grid line 2.

[0032] The welding tape 7 is laid just above the insulating adhesive 6. After the welding tape 7 is laid to the predetermined position, it is pressed toward the solar cell by a pressing net. The insulating adhesive 6 is flattened to wrap the welding tape 7 in a U shape, and the welding tape 7 is in direct contact with the continuous secondary grid line 2. In the subsequent lamination process, the welding tape 7 forms an ohmic contact with the secondary grid line.

[0033] The soldering strip 7 is a copper strip containing a coating, and its cross section is round or flat. The base copper strip plays the main role in current transmission. The coating on the outer periphery of the copper strip is a low-temperature solder, and its melting point does not exceed the lamination temperature of the photovoltaic module of 150°C. It is generally an indium or bismuth solder, and can be one of tin indium SnIn, tin-lead indium SnPbIn, tin-bismuth SnBi, tin-lead bismuth SnPbBi or tin-bismuth silver SnBiAg.

[0034] A secondary grid reinforcement section 8 is provided on the solar cell. The secondary grid reinforcement section 8 is located on the continuous secondary grid line 2, is spaced apart in the vertical direction and is located on the same straight line as the glue dispensing area 5. The secondary grid reinforcement section 8 is integrally formed with the continuous secondary grid line 2 and is located directly below the welding strip 7. Its function is to increase the contact area between the welding strip 7 and the continuous secondary grid line 2, improve the bonding strength between the welding strip 7 and the continuous secondary grid line 2, and enhance the reliability of the main grid-free photovoltaic module.

[0035] In some implementations, the auxiliary secondary grid lines 4 are strengthened.

[0036] like Figure 4Two auxiliary secondary grid lines 4 are arranged at the end points of the same segmented secondary grid line 3, which are parallel to each other and have a certain separation distance. The upper and lower ends of the two auxiliary secondary grid lines 4 are connected to the upper and lower continuous secondary grid lines 2. If the inner auxiliary secondary grid line 4 is broken during the processing, the current will be transmitted to the continuous secondary grid line 2 through the outer auxiliary secondary grid line 4, so as to prevent the occurrence of short circuit in some areas.

[0037] like Figure 5 The auxiliary auxiliary grid line 4 can also be connected to two adjacent continuous auxiliary grid lines 2 above and below. This design can prevent the inner continuous auxiliary grid line 2 from being covered by the insulating glue 6 and causing partial area disconnection. The current can be transmitted to the outer continuous auxiliary grid line 2.

[0038] The auxiliary secondary grid lines 4 can have a variety of graphic designs to form glue dispensing areas 5 of different shapes, such as Figure 6 The auxiliary secondary grid line 4 is a fold line to form a diamond-shaped glue dispensing area 5, Figure 7 The auxiliary secondary grid line 4 is an arc line, forming an arc-shaped glue dispensing area 5, which can also be as Figure 8 The auxiliary grid line 4 shown uses a 120-degree fold line to form a regular hexagonal glue dispensing area 5. Of course, it can also be designed in other shapes. The common feature is that the segmented grid line 3 is connected to the continuous grid line 2 to reserve as large a coating space as possible for the insulating glue 6.

[0039] like Figure 2 As shown, a busbarless solar cell assembly includes the above-mentioned busbarless solar cell. During installation, the welding ribbon 7 is bonded to the battery cell 1 through the insulating glue 6, and the welding ribbon 7 is connected from the positive electrode of one battery cell 1 to the negative electrode of the second battery cell 1, and the battery strings are connected in series in sequence. Then, the front glass 9, the front package 10, the battery string, the back package 11 and the back glass 12 are stacked and laid in sequence to form a stack. The stack is put into a laminator. Under high temperature and vacuum environment, the welding ribbon 7 forms an ohmic contact with the continuous secondary grid line 2, and the package melts and cross-links to form a seal.

[0040] The utility model sets auxiliary auxiliary grid lines 4 at the end points of the segmented auxiliary grid lines 3, and connects the segmented auxiliary grid lines 3 to the continuous auxiliary grid lines 2 through the auxiliary auxiliary grid lines 4, so as to prevent the disconnection caused by the segmented auxiliary grid lines 3; and the glue-dispensing area 5 surrounded by the auxiliary auxiliary grid lines 4 and the continuous auxiliary grid lines 2 at the laying position of the insulating glue 6 can effectively prevent the local disconnection caused by the deviation of the insulating glue 6 during glue-dispensing, thereby improving the power output of the solar cell.

[0041] Based on the above ideal embodiments of the utility model, the relevant staff can make various changes and modifications without deviating from the technical concept of the utility model through the above description. The technical scope of the utility model is not limited to the content of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A busbar-free solar cell, comprising a cell (1), wherein parallel busbar lines are arranged at intervals on the surface of the cell (1), and the characteristics are: The auxiliary grid lines include a continuous auxiliary grid line (2) extending continuously in the horizontal direction and a segmented auxiliary grid line (3) arranged in segments in the horizontal direction. The segmented auxiliary grid lines (3) are arranged between two continuous auxiliary grid lines (2) in an interval shape in the vertical direction. The endpoints of two adjacent segmented auxiliary grid lines (3) are respectively connected to auxiliary auxiliary grid lines (4). The upper and lower ends of the auxiliary auxiliary grid lines (4) in the vertical direction are respectively connected to the two upper and lower adjacent continuous auxiliary grid lines (2); the auxiliary auxiliary grid lines (4) and the two upper and lower adjacent continuous auxiliary grid lines (2) form a glue spotting area (5), and the glue spotting area (5) is coated with insulating glue (6), and a welding strip (7) in contact with the continuous auxiliary grid line (2) is laid on the insulating glue (6).

2. The busbar-free solar cell according to claim 1, characterized in that: The continuous secondary grid line (2) is provided with a secondary grid reinforcement section (8) formed integrally with the continuous secondary grid line (2); the secondary grid reinforcement sections (8) are spaced apart in the vertical direction and are located on the same straight line as the glue dispensing area (5).

3. The busbar-free solar cell according to claim 2, characterized in that: The glue dispensing area (5) is in the shape of a rhombus, an arc or a regular hexagon.

4. The busbar-free solar cell according to claim 1, characterized in that: The segmented auxiliary grid line (3) comprises two edge segments (3-1) and at least one middle segment (3-2).

5. The busbar-free solar cell according to claim 4, characterized in that: The end points of the two adjacent segmented auxiliary grid lines (3) are respectively connected with two auxiliary auxiliary grid lines (4) connected to the two upper and lower adjacent continuous auxiliary grid lines (2) at intervals.

6. The busbar-free solar cell according to claim 1, characterized in that: The two ends of the auxiliary secondary grid line (4) are respectively connected to at least two upper and lower adjacent continuous secondary grid lines (2).

7. A busbar-free solar cell module, characterized in that: A busbar-free solar cell according to any one of claims 1 to 6.

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