WO2024027342A1 - Solar cell and solar module - Google Patents

Abstract

The present application relates to the technical field of solar cells. Disclosed are a solar cell and a solar module, for solving the problem of low efficiency of a solar cell. The solar cell comprises a cell body and an electrode structure formed on the cell body. The electrode structure comprises a plurality of solder joints and n busbars extending in a first direction and distributed at intervals in a second direction. Each busbar comprises two busbar lines symmetrically arranged in the first direction, the two ends of the corresponding solder joints in the length direction are respectively in lap joint with two adjacent busbar lines, and the length direction of the solder joints is parallel to the second direction. The first direction is different from the second direction, the distance between two adjacent busbars is 7 mm to 13 mm, wherein 13≤n≤25, and n is an integer. The present application further provides a solar module, comprising the solar cell according to the described technical solution.

Description

A kind of solar cell and solar component

This application claims priority to the Chinese patent application filed with the China Patent Office on August 3, 2022, with application number 202222034340.9 and application title "A solar cell and solar module", the entire content of which is incorporated into this application by reference. .

Technical field

The present application relates to the technical field of solar cells, and in particular to a solar cell and a solar module.

Background technique

A solar cell is a semiconductor device that converts light energy into electrical energy. Specifically, when the solar cell is exposed to light, the semiconductor substrate included in the solar cell absorbs photons and generates electron and hole pairs. The electron and hole pairs are separated under the action of the built-in electric field of the PN junction, and are extracted through the emitter and back field of the solar cell respectively, and are finally collected by the electrode structure provided on the semiconductor substrate.

The above electrode structure generally includes 5 to 12 main grids, and the distance between the central axes of two adjacent main grids is 15 mm to 30 mm. The spacing between the central axes of the two adjacent main grids is relatively large. Although the main grids can collect current in a wider range, the cell efficiency of the solar cell will be reduced.

Application content

The purpose of this application is to provide a solar cell and a solar module for improving the cell efficiency of the solar cell.

In order to achieve the above object, in a first aspect, the present application provides a solar cell, which includes a cell body and an electrode structure formed on the cell body. The electrode structure includes a plurality of solder joints and n main grids extending along a first direction and spaced apart along a second direction. Each main grid includes two main grid lines symmetrically arranged along the first direction. Both ends of the corresponding solder joints in the length direction are respectively overlapped with two adjacent main grid lines. The length direction of the solder joints is parallel to the second direction. The first direction is different from the second direction, and the spacing between two adjacent main grids is 7 mm to 13 mm, where 13≤n≤25, and n is an integer. It should be understood that the above-mentioned spacing between two adjacent main grids refers to the spacing between the central axes of the main grids (that is, the straight line where the symmetry axis of the main grids is located) of the two adjacent main grids, and the main grid is located has a central axis parallel to the first direction.

When the above technical solution is adopted, when the size of the main body of the battery sheet is the same, it is different from the existing one. Compared with solar cells with 5BB (Bus bar) to 12BB, the electrode structure in this application includes 13 to 25 bus bars. Obviously, the solar cell provided by this application has a larger number of main grids. At this time, the range of the area where each main gate collects carriers is reduced, thereby improving the main gate's ability to collect carriers generated in this area, thereby improving the main gate's ability to collect current, and at the same time, the current can be Collection is more even. Moreover, according to the existing technology, it is known that for N-type solar cells and P-type solar cells, within a certain range, the cell efficiency tends to increase as the distance between two adjacent main grids decreases. It can be seen from this that for cell bodies of the same size, compared with the situation where the distance between two adjacent main grids is 15 mm to 30 mm in the prior art, the distance between two adjacent main grids in this application is The cell efficiency of solar cells is higher when it is 7 mm to 13 mm. That is, using the solar cell provided by the present application improves cell efficiency. Next, the number of the above-mentioned main grids can be selected according to actual needs, so that the solar cell can be suitable for different application scenarios and expand its scope of application.

Furthermore, during actual use, the main grid is connected to the welding strip. However, as the spacing between two adjacent main grids decreases, not only does the corresponding welding process need to be matched, but the diameter of the welding strip also needs to be reduced. At this time, not only does the welding process need to be more difficult, but the reduced diameter welding ribbon is easily bent during the welding process, affecting the transmission of current. Based on this, in this application, the spacing between two adjacent main grids is set to 7 mm to 13 mm. At this time, not only does the difficulty of the welding process not need to be greatly increased, but it can also ensure that the welding ribbon with a diameter that meets the requirements is not prone to bending during the welding process, thereby reducing the stress here and ensuring the yield of the solar cell.

Furthermore, since each main grid includes two main grid lines symmetrically arranged along the first direction. In actual use, when one of the main grid lines is aged or damaged, the other main grid line can still collect current normally. At this time, the impact on the solar cell can be weakened so that it can operate normally, thereby ensuring the cell efficiency of the solar cell.

In addition, compared with the prior art where there are no main grid lines and only solder joints, since the electrode structure in this application includes main grid lines and multiple solder joints overlapping the main grid lines, when the number of solder joints and When the welding qualification rate is less than or equal to the actual required quantity and welding qualification rate, the main grid wire overlapping the solder joints can replace the solder joints and connect with the welding ribbon to ensure the normal operation of the solar cell.

In one implementation, each main grid line includes a main grid connection line and a bonding line connected to the main grid connection line. Along the first direction, main grid connecting lines and bonding lines are distributed alternately. The two ends of the corresponding solder joints along the length direction are respectively overlapped with two adjacent overlap lines of each main grid, and the length direction of the solder joints is parallel to the second direction.

When the above technical solution is adopted, since the overlapping wire and the soldering point are connected, at this time, only adjusting the width of the overlapping wire can ensure that the soldering point and the main grid line are firmly connected. No adjustments are required during this process The width of the main grid connection line is simple and convenient. Furthermore, since the electrode structure includes a plurality of welding points, and the two ends of the corresponding welding points along the length direction are respectively overlapped with two adjacent overlapping lines of each main grid. At this time, compared with the situation where the ribbon is welded to the main grid line through only one solder point, the ribbon corresponding to the corresponding main grid line can be welded through the above multiple solder points, so that the soldering ribbon and the main grid line can be welded It is stronger, thereby improving the welding quality of solar cells during series welding, and ensuring the stability and safety of solar cells.

In one implementation, the width of the above-mentioned overlapping line is greater than or equal to the width of the main grid connecting line, and the width direction of the overlapping line and the width direction of the main grid connecting line are both parallel to the second direction.

When the above technical solution is adopted, when the width of the main grid connection line is small, since the width of the overlapping wire is greater than the width of the main grid connection line, the normal connection between the solder joint and the overlapping wire can be ensured at this time, thereby ensuring the later connection of the welding strip with The main grid is connected normally. Based on this, it can not only save the conductive material for making the main grid connection line, but also ensure the normal connection between the main grid and the welding ribbon.

In one implementation, along the second direction, the spacing between two adjacent connecting lines of each main grid is greater than or equal to the spacing between the corresponding two adjacent main grid connecting lines.

In an implementation manner, along the second direction, the spacing between two adjacent connecting lines of each main grid is less than or equal to the spacing between the corresponding two adjacent main grid connecting lines.

When the above technical solution is adopted, the spacing between two adjacent overlapping wires can be adjusted according to the length of the soldering point to ensure normal connection between the soldering point and the overlapping wire. Moreover, the angle between the above-mentioned overlapping line and the main grid connection line can be adjusted according to the actual situation and is not limited to a fixed value, so that the shape of the main grid line can be more selective. Based on this, the mainbar can be applied to different application scenarios, expanding its scope of application.

In an implementation manner, along the second direction, each solder joint has a shape that is narrow in the middle and wide at both ends.

When the above technical solution is adopted, since both ends of the solder joint are wide, the firmness of the connection between the solder joint and the corresponding bonding wire can be ensured. Then, when the two ends of the solder joint are made of a material with poor conductivity but cheap price, since the two ends of the solder joint are wider than the middle, at this time, a larger contact area can be used to make up for the disadvantage of poor conductivity, so as to facilitate The solder joints collect current better, thereby ensuring the speed of current transmission to the soldering strip. Furthermore, compared with the situation in the prior art where the width of the solder joints at both ends of the same conductive material is equal to the width at both ends of the solder joints in this application, this application reduces the consumption of conductive materials when making solder joints.

In one implementation, along the second direction, each solder joint includes a middle region and two end regions. The two end regions are connected to both ends of the middle region respectively, along the direction away from the corresponding main grid, The width of the end region gradually decreases, and the direction away from the corresponding main grid is parallel to the second direction. At this time, the selectivity of the end area shape of the solder joint is increased, so that it can be selected according to the actual application scenario. Based on this, the solder joints can be suitable for different application scenarios and expand their scope of application.

In one implementation, the upper surface of each middle region is rectangular, and the upper surface of each end region is trapezoidal.

In one implementation, the above electrode structure further includes a plurality of auxiliary grids extending along the second direction and spaced apart along the first direction, and each main grid intersects a plurality of auxiliary grids.

When the above technical solution is adopted, since the electrode structure also includes a plurality of sub-grids, each of the above-mentioned sub-grids can collect carriers generated in a corresponding area of the cell body. Moreover, since each main grid intersects multiple auxiliary grids. At this time, the carriers collected by all the secondary gates can be collected through each main gate. Based on this, the current collection path can be shortened to reduce the transmission resistance of carriers on the auxiliary gate to the main gate.

In one implementation, the plurality of sub-gates include at least one continuous first sub-gate and at least one non-continuous second sub-gate. The first auxiliary grid intersects with the main grid connection line, and each second auxiliary grid includes a plurality of auxiliary grid sections extending along the second direction and arranged in sequence, and the auxiliary grid sections intersect with the overlapping lines.

When the above technical solution is adopted, since the second sub-gate is discontinuous, at this time, the consumption of conductive materials when making the second sub-gate can be reduced, thereby reducing the total consumption of conductive materials when making the sub-gate, and thus can Reduce solar cell manufacturing costs. Next, compared with the prior art situation where the height of the first auxiliary gate is greater than or equal to the soldering point and the first auxiliary gate is too close to the soldering point, since the first auxiliary gate intersects with the main grid connection line, each second auxiliary gate The gate includes a plurality of auxiliary gate segments extending along the second direction and arranged in sequence, and the auxiliary gate segments intersect with the overlapping lines. At this time, it is possible to reduce or avoid the situation where the soldering strip cannot be accurately connected to the soldering point, thus ensuring the normal connection between the soldering strip and the main grid.

In one implementation, the ratio of the width of the main gate line to the width of the auxiliary gate is (1.5-2.5): 1. The width direction of the main gate line is parallel to the second direction, and the width direction of the auxiliary gate is parallel to the first direction. direction.

When the above technical solution is adopted, main gate lines and auxiliary gates of different widths can be set according to actual needs, which increases the selectivity of the main gate line and auxiliary gate widths. At this time, the electrode structure can be applied to different application scenarios and its scope of application is expanded.

In one implementation, the above electrode structure further includes end connection lines at both ends of each main grid and at least one auxiliary grid connecting each end connection line and extending in the first direction toward the edge of the cell sheet body.

When the above technical solution is adopted, the above-mentioned end connection lines and auxiliary grids can collect carriers generated there by the main body of the cell, just like the solder joints or main grid lines. Moreover, since the edge of the solar cell The edge part has a certain degree of brittleness and is easily broken when heated. Based on this, in this application, the above-mentioned auxiliary grid does not need to be welded with the welding strip. At this time, the edge portion of the solar cell can be prevented from being broken due to the high temperature of the thermal welding process during the series welding process. Based on this, not only can the safety and stability of solar cells be improved, but the production yield of solar cells can also be improved.

In one implementation, the width of the auxiliary grid gradually decreases along the direction close to the edge of the cell body, and the width direction of the auxiliary grid is parallel to the second direction.

When the above technical solution is adopted, the current is smaller closer to the edge of the battery sheet body, and the current is larger closer to the inner area of the battery sheet body. Therefore, in this application, the shape of the auxiliary grid is designed such that the width of the auxiliary grid gradually decreases along the direction close to the edge of the cell body. At this time, not only the current collection effect can be ensured, but also the cell efficiency of the solar cell can be ensured. At the same time, the conductive material for making the auxiliary grid can also be saved to reduce the consumption of conductive materials, thereby reducing the manufacturing cost of solar cells.

In one implementation, the above-mentioned electrode structure further includes a reinforcing member, and the reinforcing member is disposed between two adjacent auxiliary grids.

When the above technical solution is adopted, since the edge part of the solar cell has a certain degree of brittleness, it is easy to crack during use. Based on this, in this application, a reinforcing member is provided between two adjacent auxiliary grids. At this time, the above-mentioned reinforcement members can be used to increase the strength of the edge portion of the solar cell to reduce the probability of cracking and thereby improve the quality of the solar cell.

In one implementation, the above-mentioned electrode structure further includes end solder joints. Both ends of the corresponding end solder joints along the length direction are respectively overlapped with two adjacent end connecting lines. The length direction of the end solder joints is parallel to Second direction.

When the above technical solution is adopted, in this application, since the end solder joint overlaps with the end connection line and does not overlap with the auxiliary grid, at this time, it is possible to prevent the edge part of the solar cell from overlapping with the auxiliary grid. When welding the welding strip at the lower solder joints, the welding strip will break due to the high temperature of the thermal welding process. Based on this, not only can the safety and stability of solar cells be improved, but the production yield of solar cells can also be improved.

In an implementation manner, the width of the main grid connection line is 0.1 mm to 0.5 mm, and the width of the bonding line is 0.2 mm to 0.6 mm.

When the above technical solution is adopted, the selectivity of the width of the main grid connection line and the width of the bonding line is increased, so that the main grid line can be applied to different application scenarios and expands its scope of application.

In one implementation, the above electrode structure is applied to the positive electrode and/or the negative electrode of the solar cell; and/or the solar cell is a whole solar cell or a sliced solar cell.

In a second aspect, this application also provides a solar component, including the solar cell as described in the first aspect.

Compared with the prior art, the beneficial effects of the solar module provided by the present application are the same as those of the solar cell described in the first aspect, and will not be described again here.

The above description is only an overview of the technical solutions of the present application. In order to have a clearer understanding of the technical means of the present application, they can be implemented according to the content of the description, and in order to make the above and other purposes, features and advantages of the present application more obvious and understandable. , the specific implementation methods of the present application are specifically listed below.

Description of the drawings

In order to more clearly explain the embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description These are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without exerting creative efforts.

The drawings described here are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation of the present application. In the attached picture:

Figure 1 is a partial structural diagram of a solar cell in an embodiment of the present application;

Figure 2 is a schematic structural diagram of the main grid in the embodiment of the present application;

Figure 3 is a schematic diagram of the relationship between main grid spacing and battery efficiency in the embodiment of the present application;

Figure 4 is a schematic structural diagram of the first part of the main grid in the embodiment of the present application;

Figure 5 is an enlarged schematic diagram of part of the structure of Figure 4 in the embodiment of the present application;

Figure 6 is a top view of the solder joint in the embodiment of the present application;

Figure 7 is a schematic structural diagram of the second part of the main grid in the embodiment of the present application;

Figure 8 is a schematic diagram of the assembly structure of the second part of the main grid and the reinforcement in the embodiment of the present application;

FIG. 9 is an enlarged schematic diagram of part of the structure of FIG. 8 in an embodiment of the present application.

Reference signs:
1-Battery body, 2-Electrode structure, 20-Solder points,
200-middle area, 201-end area, 21-main grid,
210-main grid line, 2100-main grid connecting line, 2101-overlapping line,
22-auxiliary grid, 220-first auxiliary grid, 221-second auxiliary grid,
2210-auxiliary grid section, 23-end connecting line, 24-auxiliary grid,
25-reinforcement, 26-end welding point, A-first direction,
B-Second direction.

Specific embodiments

In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments These are part of the embodiments of this application, but not all of them. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of this application.

In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clear, this application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present application and are not used to limit the present application.

The terms "first", "second", "third", "fourth", etc. (if present) in the description and claims of this application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used for Describe a specific order or sequence. It is to be understood that the data so used are interchangeable under appropriate circumstances so that the embodiments of the application described herein can, for example, be practiced in sequences other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, e.g., a process, method, system, product, or apparatus that encompasses a series of steps or units and need not be limited to those explicitly listed. Those steps or elements may instead include other steps or elements not expressly listed or inherent to the process, method, product or apparatus.

The technical solution of the present application will be described in detail below with reference to specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments.

The length and width of existing solar cells are generally 150 mm to 230 mm. The electrode structure includes 5 to 12 main grids, and the distance between the central axes of two adjacent main grids is generally 15 mm. to 30 mm. The spacing between the central axes of the two adjacent main grids is relatively large. Although the main grids can collect current in a wider range, the cell efficiency of the solar cell will be reduced. In addition, in order to ensure that each main grid has a certain current collection capability, the width of each main grid needs to be set to a larger value, such as greater than 300 microns.

Embodiments of the present application provide a solar cell. From a structural perspective, the solar cell includes positive electrodes and negative electrodes located on opposite sides of the solar cell. In terms of division, the solar cell can be a whole solar cell or a sliced solar cell. Among them, when the solar cell is a sliced solar cell, the division multiple can be set according to actual needs.

In the first aspect, referring to FIGS. 1 and 2 , the solar cell may include a cell body 1 and an electrode structure 2 formed on the cell body 1 . The above-mentioned electrode structure 2 may include a plurality of welding spots 20 and n main grids 21 extending along the first direction and spaced apart along the second direction. Each main grid 21 includes two main grid lines 210 symmetrically arranged along the first direction. Both ends of the corresponding welding point 20 in the length direction overlap with two adjacent main grid lines 210 respectively. The length direction of the welding point 20 is parallel. in the second direction. The first direction is different from the second direction, and the spacing between two adjacent main grids 21 is 7 mm to 13 mm, where 13≤n≤25, and n is an integer. For example, the pitch may be 7 mm, 8 mm, 8.5 mm, 8.9 mm, 9.2 mm, 10 mm, 12 mm or 13 mm, etc. n can be 13, 15, 16, 18, 20 or 25 etc. It should be understood that the above-mentioned spacing between two adjacent main grids 21 refers to the spacing between the central axes of the two adjacent main grids 21 (that is, the straight line where the symmetry axis of the main grids 21 is located). And the central axis of the main grid 21 is parallel to the first direction.

The structure, specifications, etc. of the above-mentioned battery sheet body can be set according to the actual situation, and are not specifically limited here. The above electrode structure may be applied only to the positive electrode included in the solar cell, or may be applied only to the negative electrode included in the solar cell, or may be applied to both the positive electrode and the negative electrode included in the solar cell.

The above-mentioned first direction and the second direction may be any two directions that are parallel to the surface of the main body of the battery sheet and are different from each other. Preferably, referring to Figures 1 and 2, the above-mentioned first direction A and second direction B are orthogonal. At this time, the plurality of main grids 21 can be arranged at intervals along the row direction and extend along the column direction, that is, evenly distributed on the cell body 1 in an array.

Referring to Figures 1 and 2, when the size of the cell body 1 is the same, compared with the existing 5BB (Bus bar) to 12BB solar cells, the electrode structure 2 in the embodiment of the present application includes 13 to 25 strips. Main grid 21. Obviously, the solar cell provided by the embodiment of the present application has a larger number of main grids. At this time, the range of the area where each main grid 21 collects carriers is reduced, thereby improving the main grid 21's ability to collect carriers generated in this area, thereby improving the main grid's 21 ability to collect current, while also improving the current collection ability of the main grid 21. Can make current collection more uniform. Moreover, according to the existing technology, it is known that for N-type solar cells and P-type solar cells, within a certain range (for example, the distance between adjacent main grids 21 is 8.5 mm to 18.2 mm), the cell efficiency increases with the The spacing between the gates 21 decreases and shows an increasing trend. It can be seen from this that for the cell body 1 of the same size, compared with the prior art where the distance between two adjacent main grids 21 is 15 mm to 30 mm, the distance between two adjacent main grids 21 in the embodiment of the present application is The cell efficiency of solar cells is higher when the spacing between 21 is 7 mm to 13 mm. That is, the solar cell provided by the embodiment of the present application improves the cell efficiency. Specifically, referring to Figure 3, it can be seen that in theory, for small sheet resistance (for example, generally 100Ω/□ to 130Ω/□) N-type solar cells, when the distance between two adjacent main grids is 8.5 mm, the cell efficiency of N-type solar cells reaches the limit value. The spacing between the two adjacent main grids is 8.5 mm, which corresponds to a 182-sized 20BB solar cell. For P-type solar cells with large sheet resistance (for example, generally 180Ω/□ to 200Ω/□), when the distance between two adjacent main grids is 7.9 mm, the cell efficiency of the P-type solar cell reaches the limit value. The spacing between the two adjacent main grids is 7.9 mm, which corresponds to the 22BB solar cell with 182 specifications.

Next, the number of the above-mentioned main grids can be selected according to actual needs, so that the solar cell can be suitable for different application scenarios and expand its scope of application.

Furthermore, during actual use, the main grid is connected to the welding strip. However, as the spacing between two adjacent main grids decreases, not only does the corresponding welding process need to be matched, but the diameter of the welding strip also needs to be reduced. At this time, not only does the welding process need to be more difficult, but the reduced diameter welding ribbon is easily bent during the welding process, affecting the transmission of current. Based on this, in the embodiment of the present application, the spacing between two adjacent main grids is set to 7 mm to 13 mm. At this time, not only does the difficulty of the welding process not need to be greatly increased, but it can also ensure that the welding ribbon with a diameter that meets the requirements is not prone to bending during the welding process, thereby reducing the stress here and ensuring the yield of the solar cell. For example, the spacing between adjacent main grids is 8.5 mm to 9.5 mm, and can be welded with a welding strip with a diameter of 0.23 mm to 0.25 mm. In this case, it can not only meet the needs of mass production, but also save the manufacturing cost of solar cells. For example, when the spacing between adjacent main grids is 9.5 mm, it corresponds to an 18BB solar cell.

Further, referring to FIGS. 1 and 2 , each main grid 21 includes two main grid lines 210 symmetrically arranged along the first direction. In actual use, when one of the main grid lines 210 is aged or damaged, the other main grid line 210 can still collect current normally. At this time, the impact on the solar cell can be weakened so that it can operate normally, thereby ensuring the cell efficiency of the solar cell. Next, since the main grid line 210 can be used to collect current. Based on this, the battery efficiency can be tested.

In addition, compared with the prior art where there are no main grid lines and only solder joints, since the electrode structure in this application includes main grid lines and multiple solder joints overlapping the main grid lines, when the number of solder joints and When the welding qualification rate is less than or equal to the actual required quantity and welding qualification rate, the main grid wire overlapping the solder joints can replace the solder joints and connect with the welding ribbon to ensure the normal operation of the solar cell.

The number of main grids included in the above electrode structure, the spacing between two adjacent main grids in this number, and the spacing between two main grid lines included in the main grid can be set according to actual conditions. It should be understood that the area between the two main gate lines may or may not be filled with conductive material. The materials can be set according to the actual situation and are not specifically limited here. For example, if the area between the two main grid lines is not filled with conductive material, the cost of manufacturing the solar cell can be reduced.

Two possible implementations are taken as examples for description below. It should be understood that the following description is only for understanding and not for specific limitation.

Example 1: The above electrode structure includes 16 main grids extending along a first direction and spaced apart along a second direction. The first direction is different from the second direction. The distance between two adjacent main grids is 10.7 mm.

Example 2: The above electrode structure includes 18 main grids extending along a first direction and spaced apart along a second direction. The first direction is different from the second direction, and the spacing between two adjacent main grids is 9.5 mm.

It can be seen from Figure 3 that in the above two examples, the cell efficiency of the solar cell is also greater than that in the prior art when the distance between two adjacent main grids is 15 mm to 30 mm. Moreover, since the spacing between two adjacent main grids is 10.7 mm or 9.5 mm, this not only further reduces the difficulty of the welding process, but also ensures that the welding strip with a diameter that meets the requirements is less likely to bend during the welding process. This can then reduce the stress here and ensure the yield of the solar cell.

As a possible implementation, referring to FIG. 2 , each main grid line 210 may include a main grid connection line 2100 and a bonding line 2101 connected to the main grid connection line 2100 . Along the first direction, the main grid connection lines 2100 and the bonding lines 2101 are alternately distributed. Both ends of the corresponding welding point 20 along the length direction are respectively overlapped with two adjacent overlapping lines 2101 of each main grid, and the length direction of the welding point is parallel to the second direction.

Referring to Figure 2, since the bonding wire 2101 is connected to the welding point 20, at this time, only adjusting the width of the bonding line 2101 can ensure that the welding point 20 and the main grid line 210 are firmly connected. In this process, there is no need to adjust the width of the main gate connection line 2100, which is simple and convenient. Furthermore, since the electrode structure 2 includes a plurality of welding points 20, and the two ends of the corresponding welding points 20 along the length direction are respectively overlapped with two adjacent overlapping lines 2101 of each main grid. At this time, compared with the situation where the soldering ribbon is welded to the main grid line 210 through only one soldering point, the soldering ribbon corresponding to the corresponding main grid line 210 can be welded through the above-mentioned multiple soldering points, so that the soldering ribbon and the main grid line can be welded together. 210 welding is stronger, thereby improving the welding quality of solar cells when welding in series, ensuring the stability and safety of solar cells.

The two ends of the above-mentioned corresponding soldering points along the length direction are respectively overlapped with two adjacent overlapping wires in various ways. For example, they can be integrally formed, or the overlapping wires can be provided after the soldering points are set.

In an optional manner, the above-mentioned solder joints and corresponding bonding wires are integrally formed. At this time, not only can the probability of misalignment between the solder joints and the corresponding bonding wires be reduced or eliminated to ensure the quality of the solar cell, but the preparation efficiency can also be improved.

In an optional manner, referring to Figure 2, the width of the above-mentioned bonding line 2101 is greater than or equal to the width of the main grid connection line 2100, and the width direction of the bonding line 2101 and the width direction of the main grid connection line 2100 are both parallel to the first Two directions.

Referring to Figure 2, when the width of the main gate connecting line 2100 is small, since the width of the bonding wire 2101 is greater than the width of the main gate connecting line 2100, the normal connection between the solder joint and the bonding line 2101 can be ensured at this time, thereby ensuring that the welding strip is connected to the bonding wire in the later stage. The main grid is connected normally. Based on this, the conductive material for making the main grid connection line 2100 can not only be saved, but also the normal connection between the main grid and the soldering strip can be ensured.

As a possible implementation manner, the width of the main grid connection line is 0.1 mm to 0.5 mm, for example, 0.1 mm, 0.15 mm, 0.2 mm, 0.27 mm, 0.3 mm or 0.5 mm, etc. The width of the above-mentioned bonding wire is 0.2 mm to 0.6 mm, for example, 0.2 mm, 0.25 mm, 0.3 mm, 0.4 mm, 0.5 mm or 0.6 mm, etc. When the above technical solution is adopted, the selectivity of the width of the main grid connection line and the width of the bonding line is increased, so that the main grid line can be applied to different application scenarios and expands its scope of application. In the embodiment of the present application, the width of the main grid connection line is 0.3 mm, and the width of the bonding line is 0.3 mm.

The relationship between the spacing between two adjacent bonding lines of each main grid and the spacing between two adjacent main grid connecting lines can be set according to the actual situation. Two possible implementation methods are taken as examples below. Description is made, and it should be understood that the following description is only for understanding and not for specific limitation.

As a possible implementation, see Figure 2. Along the second direction, the spacing between two adjacent connecting lines 2101 of each main grid is greater than or equal to the distance between the corresponding two adjacent main grid connecting lines 2100. Pitch.

As another possible implementation manner, along the second direction, the spacing between two adjacent connecting lines of each main grid is less than or equal to the spacing between the corresponding two adjacent main grid connecting lines.

When the above technical solution is adopted, see Figure 2, the spacing between two adjacent bonding wires 2101 can be adjusted according to the length of the soldering point to ensure normal connection between the soldering point and the bonding wire 2101. Moreover, the angle between the above-mentioned bonding line 2101 and the main grid connection line 2100 can be adjusted according to actual conditions and is not limited to a fixed value, so that the shape of the main grid line 210 can be more selective. Based on this, the mainbar can be applied to different application scenarios, expanding its scope of application.

For example, when the length of the welding point is long, the spacing between two adjacent bonding lines can be increased without changing the width of the bonding line. That is, make the distance between two adjacent bonding lines The spacing is larger than the spacing between two adjacent busbar connection lines.

The upper surface of the above-mentioned solder joint has various shapes, and the above-mentioned "upper surface" refers to the surface of the solder joint seen when looking down at the solar cell. Two possible shapes are taken as examples for description below. It should be understood that the following description is only for understanding and not for specific limitation.

As a possible implementation manner, referring to FIG. 4 , along the second direction, the upper surface of each solder joint 20 is rectangular. The size of the above solder joints can be set according to the actual situation and is not specifically limited here.

For example, referring to FIG. 4 , along the second direction, the length of the above-mentioned solder joint 20 is 0.6 mm to 2 mm, for example, 0.6 mm, 0.7 mm, 0.8 mm, 1 mm, 0.15 mm or 2 mm, etc. Along the first direction, the width of the above-mentioned solder joint 20 is 0.12 mm to 1.5 mm, for example, 0.12 mm, 0.32 mm, 0.8 mm, 1 mm, 1.25 mm or 1.5 mm, etc. Along the second direction, the width W1 of the overlap between the solder joint 20 and the bonding wire 2101 is 50 microns to 200 microns, for example, 50 microns, 65 microns, 80 microns, 100 microns, 150 microns or 200 microns. In the embodiment of the present application, the length of the above-mentioned solder joint is 1.6 mm, the width of the solder joint is 0.15 mm, and the width W1 of the overlap is 100 μm.

As another possible implementation, referring to FIG. 5 , along the second direction, each solder joint 20 has a shape that is narrow in the middle and wide at both ends.

When the above technical solution is adopted, as shown in FIG. 5 , since the two ends of the soldering point 20 are wide, the firmness of the connection between the soldering point 20 and the corresponding bonding wire can be ensured. Next, when the two ends of the solder joint 20 are made of a material with poor conductivity but cheap price, since the two ends of the solder joint 20 are wider than the middle, at this time, a larger contact area can be used to make up for the disadvantage of poor conductivity. In order to facilitate the welding point 20 to better collect current, thereby ensuring the speed of current transmission to the welding strip. Furthermore, compared with the situation in the prior art where the width of the same conductive material is equal to the width at both ends of the solder joint in the embodiment of the present application, the consumption of conductive material when making the solder joint is reduced in the embodiment of the present application. quantity.

In an optional manner, referring to FIGS. 5 and 6 , along the second direction, each soldering point 20 may include a middle region 200 and two end regions 201 . The two end regions 201 are respectively connected to both ends of the middle region 200. The width of the end regions 201 gradually decreases along the direction away from the corresponding main grid, and the direction away from the corresponding main grid is parallel to the second direction. At this time, the selectivity of the shape of the end area 201 of the solder joint is increased, so that it can be selected according to the actual application scenario. Based on this, the solder joints can be suitable for different application scenarios and expand their scope of application.

In an optional manner, along the second direction, the above-mentioned end area is an axially symmetrical figure.

In an optional manner, see FIG. 6 , the upper surface of each middle area 200 is rectangular. shape, and the upper surface of each end region 201 is trapezoidal. The above-mentioned trapezoid may be a right-angled trapezoid, an isosceles trapezoid or other trapezoids.

In an optional manner, the upper surface of each middle region is rectangular, and the upper surface of each end region is a gradient shape. The above gradient shape may be a shape enclosed by straight lines and curves. The specifications of the end area of the gradient shape are not specifically limited here, as long as they meet actual needs.

In an alternative, the middle area of the solder joint is made of silver paste and the end areas are made of aluminum paste. Since the unit price of aluminum is less than that of silver, at this time, compared with solder joints made of silver paste in the prior art, in the embodiment of the present application, the cost of making solder joints is reduced, thereby reducing the cost of solar energy. Battery manufacturing costs.

As a possible implementation, referring to FIG. 4 , the above electrode structure may also include a plurality of auxiliary grids 22 extending along the second direction and spaced apart along the first direction, and each main grid intersects a plurality of auxiliary grids 22 .

Since the electrode structure also includes a plurality of sub-grids, each of the above-mentioned sub-grids can collect carriers generated in a corresponding area of the cell body. Moreover, since each main grid intersects multiple auxiliary grids. At this time, the carriers collected by all the secondary gates can be collected through each main gate. Based on this, the current collection path can be shortened to reduce the transmission resistance of carriers on the auxiliary gate to the main gate. It should be understood that the number and specifications of the sub-grids included in the electrode structure, as well as the spacing between two adjacent sub-grids, can be set according to actual needs, and are not specifically limited here.

In an optional manner, referring to FIG. 4 , the plurality of auxiliary gates 22 may include at least one continuous first auxiliary gate 220 and at least one discontinuous second auxiliary gate 221 . The first auxiliary gate 220 intersects the main gate connection line. Each second auxiliary gate 221 includes a plurality of auxiliary gate segments 2210 extending along the second direction and arranged in sequence. The auxiliary gate segments 2210 intersect with the overlapping lines.

When the above technical solution is adopted, see FIG. 4 , since the second sub-gate 221 is discontinuous, at this time, the consumption of conductive materials when making the second sub-gate 221 can be reduced, so as to reduce the consumption of conductive materials when making the sub-gate. total consumption, which in turn can reduce the manufacturing cost of solar cells. Next, compared with the situation in the prior art where the height of the first auxiliary gate 220 is greater than or equal to the soldering point and the first auxiliary gate 220 is too close to the soldering point, since the first auxiliary gate 220 intersects with the main grid connection line, each The second auxiliary gate 221 includes a plurality of auxiliary gate segments 2210 extending along the second direction and arranged in sequence. The auxiliary gate segments 2210 intersect with the overlapping lines. At this time, it is possible to reduce or avoid the situation where the soldering strip cannot be accurately connected to the soldering point, thus ensuring the normal connection between the soldering strip and the main grid.

Exemplarily, the width of the above-mentioned sub-gate can be 50 microns to 150 microns, for example, it can be 50 microns. Micron, 60 micron, 80 micron, 100 micron or 150 micron, etc. The spacing between two connected auxiliary grids can be 0.6 mm to 1.8 mm, for example, it can be 0.6 mm, 0.8 mm, 1 mm, 1.2 mm, 1.5 mm or 1.8 mm, etc. Along the first direction, four second auxiliary grids are provided between the first auxiliary grid and the solder joints.

In an optional manner, the ratio of the width of the main gate line to the width of the sub-gate is (1.5-2.5):1, for example, it can be 1.5:1, 1.7:1, 2:1 or 2.5:1, etc. . The width direction of the main gate lines is parallel to the second direction, and the width direction of the auxiliary gate lines is parallel to the first direction. When the above technical solution is adopted, main gate lines and auxiliary gates of different widths can be set according to actual needs, which increases the selectivity of the main gate line and auxiliary gate widths. At this time, the electrode structure can be applied to different application scenarios and its scope of application is expanded. In actual use, the width of the main gate line can be set in advance, and then the width of the sub gate can be selected using the ratio of the width of the main gate line and the width of the sub gate set in advance.

In an optional manner, the main grid wiring and the auxiliary grid may have a three-dimensional trapezoidal structure. At this time, the aspect ratio of the main gate line may be 1:(6-8), such as 1:6, 1:7, 1:7.5 or 1:8, etc. The aspect ratio of the sub-gate can be 1: (1-5), such as 1:1, 1:1.7, 1:2, 1:3, 1:4 or 1:5, etc.

As a possible implementation, referring to Figure 7, the above-mentioned electrode structure may also include end connection lines 23 at both ends of each main grid and connecting each end connection line 23 and extending in the first direction toward the edge of the battery sheet body. at least one auxiliary gate 24.

When the above technical solution is adopted, see FIG. 7 , the above-mentioned end connection lines 23 and auxiliary grids 24 can collect the carriers generated there by the main body of the cell, just like the solder joints or main grid lines. Moreover, since the edges of solar cells are brittle, they are easily broken when heated. Based on this, in the embodiment of the present application, the above-mentioned auxiliary grid 24 does not need to be welded with the soldering strip. At this time, the edge portion of the solar cell can be prevented from being broken due to the high temperature of the thermal welding process during the series welding process. Based on this, not only can the safety and stability of solar cells be improved, but the production yield of solar cells can also be improved.

For example, the number of auxiliary gates included in the above electrode structure can be set according to actual needs. In the embodiment of the present application, referring to FIG. 7 , each electrode structure includes two auxiliary gates 24 .

The upper surface of the above-mentioned auxiliary grid has various shapes, and the above-mentioned "upper surface" refers to the surface of the auxiliary grid seen when looking down at the solar cell. Two possible shapes are taken as examples for description below. It should be understood that the following description is only for understanding and not for specific limitation.

In an optional manner, the upper surface of the above-mentioned auxiliary grid is rectangular. The specific specifications of the auxiliary grid can be set according to actual conditions and are not specifically limited here.

In another optional manner, see FIG. 7 , the width of the auxiliary grid 24 gradually decreases along the direction close to the edge of the cell sheet body, and the width direction of the auxiliary grid 24 is parallel to the second direction.

When the above technical solution is adopted, see Figure 7. Since the current is smaller closer to the edge of the battery sheet body, the current is larger closer to the inner area of the battery sheet body. Therefore, in the embodiment of the present application, the shape of the auxiliary grid 24 is designed such that the width of the auxiliary grid 24 gradually decreases along the direction close to the edge of the cell body. At this time, not only the current collection effect can be ensured, but also the cell efficiency of the solar cell can be ensured. At the same time, the conductive material for making the auxiliary grid 24 can also be saved, thereby reducing the consumption of conductive materials, thereby reducing the manufacturing cost of the solar cell.

For example, the width of the auxiliary grid close to the edge of the cell body is 0.2 mm to 0.6 mm, for example, 0.2 mm, 0.3 mm, 0.36 mm, 0.4 mm, 0.56 mm or 0.6 mm, etc. The width of the above-mentioned end connection line near the middle area of the cell body is 0.5 mm to 1.5 mm, for example, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 1 mm or 1.5 mm, etc. The width of the auxiliary grid near the edge of the cell body is less than or equal to the width of the end connection line near the middle area of the cell body. In the embodiment of the present application, the width of the above-mentioned auxiliary grid near the edge of the cell body is 0.3 mm, and the width of the end connection line near the middle area of the cell body is 1 mm.

In an optional manner, referring to FIG. 8 , the above-mentioned electrode structure may further include a reinforcing member 25 , and the reinforcing member 25 is disposed between two adjacent auxiliary grids 24 .

When the above technical solution is adopted, see Figure 8. Since the edge part of the solar cell has a certain degree of brittleness, it is easy to crack during use. Based on this, in the embodiment of the present application, a reinforcing member 25 is provided between two adjacent auxiliary grids 24 . At this time, the above-mentioned reinforcing member 25 can be used to increase the strength of the edge portion of the solar cell to reduce the probability of cracking, thereby improving the quality of the solar cell.

For example, referring to FIG. 8 , the size and the material used for making the above-mentioned reinforcement 25 can be set according to the actual situation, and are not specifically limited here. For example, along the first direction, the length of the above-mentioned reinforcement member 25 is equal to the distance from the first sub-grid to the fourth sub-grid among the four adjacent sub-grids. The above-mentioned reinforcing member 25 is formed by printing aluminum paste. Since the unit price of aluminum is low, the manufacturing cost of the reinforcing member 25 can be reduced at this time.

In an optional manner, referring to FIGS. 7 to 9 , the above electrode structure may also include end welding points 26 , and both ends of the corresponding end welding points 26 along the length direction are connected to two adjacent end connection lines 23 respectively. Overlapping, the length direction of the end solder joint 26 is parallel to the second direction.

In the case of adopting the above technical solution, referring to Figure 7 to Figure 9, in the embodiment of the present application, due to The end welding point 26 overlaps the end connection line 23 and does not overlap the auxiliary grid 24. At this time, it can prevent the edge part of the solar cell from welding the ribbon at the end welding point 26 that overlaps the auxiliary grid 24. Breakage occurs due to the high temperatures of the thermal welding process. Based on this, not only can the safety and stability of solar cells be improved, but the production yield of solar cells can also be improved. In addition, the shape of the above-mentioned end solder joint 26 may be consistent with the shape of the solder joint described above, and is not specifically limited here.

For example, referring to FIG. 9 , along the second direction, the length of the above-mentioned end welding point 26 is 0.6 mm to 2 mm, for example, 0.6 mm, 0.7 mm, 0.8 mm, 1 mm, 0.15 mm or 2 mm, etc. Along the first direction, the width of the above-mentioned end welding point 26 is 0.12 mm to 1.5 mm, for example, 0.12 mm, 0.32 mm, 0.8 mm, 1 mm, 1.25 mm or 1.5 mm, etc. Along the second direction, the width W2 of the overlap between the end solder joint 26 and the end connection line 23 is 50 microns to 200 microns, for example, 50 microns, 65 microns, 80 microns, 100 microns, 150 microns or 200 microns, etc. . In the embodiment of the present application, the length of the above-mentioned end welding point 26 is 1.6 mm, the width of the end welding point 26 is 0.4 mm, and the width W2 of the overlap is 100 microns.

As a possible implementation manner, the conductive material used to make the main grid and the auxiliary grid may be metal, for example, silver paste, aluminum paste, silver-aluminum paste, or copper.

For example, when both the main grid and the auxiliary grid are made of aluminum paste, since the conductivity of the aluminum paste is worse than that of silver paste, in order to obtain the same conductive effect as the main grid and auxiliary grid made of silver paste , it is necessary to increase the area of the main grid and auxiliary grid. Compared with the main grid and the auxiliary grid made of silver paste in the embodiment of the present application, at this time, the shielding area of the main grid and the auxiliary grid on the main body of the cell is increased. Based on this, electrode structures made of aluminum paste are preferably used on the back side of solar cells. It is understandable that the gap between the unit price of silver and the unit price of aluminum is larger than the increase in the area of the main gate and sub-gate. Therefore, when manufacturing electrode structures made of aluminum paste, the manufacturing cost of solar cells can be reduced.

As a possible implementation manner, the above-mentioned main grid and auxiliary grid may be formed by printing and sintering, laser transfer, or electroplating.

In a second aspect, embodiments of the present application further provide a solar component, including the solar cell as described in the first aspect.

The beneficial effects of the solar modules provided by the embodiments of the present application are the same as the beneficial effects of the solar cells described in the first aspect, and will not be described again here.

In the above description of the embodiments, specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

It should be noted that for the method embodiments, for the sake of simple description, they are all expressed as one A series of action combinations, but those skilled in the art should know that the embodiments of the present application are not limited by the described action sequence, because according to the embodiments of the present application, certain steps can be performed in other orders or at the same time. Secondly, those skilled in the art should also know that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily necessary for the embodiments of the present application.

It should be noted that, in this document, the terms "comprising", "comprises" or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article or device that includes a series of elements not only includes those elements, It also includes other elements not expressly listed or inherent in the process, method, article or apparatus. Without further limitation, an element defined by the statement "comprises a..." does not exclude the presence of additional identical elements in a process, method, article or apparatus that includes that element.

The embodiments of the present application have been described above in conjunction with the accompanying drawings. However, the present application is not limited to the above-mentioned specific implementations. The above-mentioned specific implementations are only illustrative and not restrictive. Those of ordinary skill in the art will Inspired by this application, many forms can be made without departing from the purpose of this application and the scope protected by the claims, and these all fall within the protection of this application.

Claims (18)

A solar cell, the solar cell includes a cell body and an electrode structure formed on the cell body; The electrode structure includes a plurality of solder joints and n main grids extending along the first direction and spaced apart along the second direction. Each of the main grids includes two main grid lines symmetrically arranged along the first direction; correspondingly Both ends of the soldering point along the length direction are respectively overlapped with two adjacent main grid lines, and the length direction of the soldering point is parallel to the second direction; the first direction is different from the second direction. direction; the spacing between two adjacent main grids is 7 mm to 13 mm, where 13≤n≤25, and n is an integer. The solar cell according to claim 1, wherein each main grid line includes a main grid connection line and a bonding line connected to the main grid connection line; along the first direction, the main grid The connecting wires and the bonding wires are distributed alternately; The two ends of the corresponding welding spots along the length direction are respectively overlapped with two adjacent overlapping lines of each main grid, and the length direction of the welding spots is parallel to the second direction. The solar cell according to claim 2, wherein the width of the bonding line is greater than or equal to the width of the main grid connecting line, and the width direction of the bonding line and the width direction of the main grid connecting line are both parallel to the second direction. The solar cell according to claim 2, wherein, along the second direction, the spacing between two adjacent bonding lines of each main grid is greater than or equal to the distance between the corresponding two adjacent bonding lines. The spacing between busbar connecting lines. The solar cell according to claim 2, wherein, along the second direction, the distance between two adjacent bonding lines of each main grid is less than or equal to the corresponding two adjacent bonding lines. The spacing between busbar connecting lines. The solar cell according to claim 1, wherein along the second direction, each of the solder joints has a shape that is narrow in the middle and wide at both ends. The solar cell according to claim 6, wherein, along the second direction, each solder joint includes a middle region and two end regions; the two end regions are respectively connected to two ends of the middle region. Connection; along the direction away from the corresponding main grid, the width of the end region gradually decreases; the direction away from the corresponding main grid is parallel to the second direction. The solar cell according to claim 7, wherein the upper surface of each middle region is rectangular, and the upper surface of each end region is trapezoidal. The solar cell according to claim 2, wherein the electrode structure further includes a plurality of auxiliary grids extending along the second direction and spaced apart along the first direction; each of the main grids is connected to a plurality of auxiliary grids. The secondary gates intersect. The solar cell according to claim 9, wherein the plurality of auxiliary grids include at least one continuous first auxiliary grid and at least one discontinuous second auxiliary grid; The first auxiliary gate intersects the main gate connection line; each of the second auxiliary gates includes a plurality of auxiliary gate segments extending along the second direction and arranged in sequence, and the auxiliary gate segments are connected to the overlapping Wires intersect. The solar cell according to claim 9, wherein the ratio of the width of the main grid line to the width of the auxiliary grid is (1.5-2.5):1; the width direction of the main grid line is parallel to the first In two directions, the width direction of the auxiliary gate is parallel to the first direction. The solar cell according to claim 1, wherein the electrode structure further includes end connection lines at both ends of each main grid and connecting each of the end connection lines and facing the battery in a first direction. At least one auxiliary grid extends from the edge of the main body of the sheet. The solar cell according to claim 12, wherein the width of the auxiliary grid gradually decreases along the direction close to the edge of the main body of the cell sheet; the width direction of the auxiliary grid is parallel to the second direction. The solar cell according to claim 12, wherein the electrode structure further includes a reinforcing member, and the reinforcing member is disposed between two adjacent auxiliary grids. The solar cell according to claim 12, wherein the electrode structure further includes an end solder joint; correspondingly, two ends of the end solder joint along the length direction are respectively overlapped with two adjacent end connecting lines. , the length direction of the end solder joint is parallel to the second direction. The solar cell according to claim 2, wherein the main grid connection line has a width of 0.1 mm to 0.5 mm; and the bonding line has a width of 0.2 mm to 0.6 mm. The solar cell according to claim 1, wherein the electrode structure is applied to the positive electrode and/or the negative electrode of the solar cell; and/or, The solar cell is a whole solar cell or a sliced solar cell. A solar component, including the solar cell according to any one of claims 1-17.