Solar cell and solar cell module

Abstract

The utility model discloses a solar cell and a solar cell assembly, which relates to the technical field of solar cells, in order to solve the problem that the use of medium-width bus electrodes in the prior art increases the manufacturing cost of the bus electrodes, resulting in an increase in the manufacturing cost of solar cells. The solar cell comprises: a bus electrode formed on the battery body, a plurality of bus electrodes extending along a first direction and distributed at intervals along a second direction, and the first direction is different from the second direction. A collector electrode formed on the battery body, a plurality of collector electrodes extending along the second direction and distributed at intervals along the first direction. Each bus electrode intersects with a plurality of collector electrodes of the same polarity. An edge negative bus electrode is provided in the edge region of the battery body, and an intermediate negative bus electrode is provided in the non-edge region of the battery body. On the same standard line, the width of the edge negative bus electrode is less than the width of the intermediate negative bus electrode, and the length extension direction of the standard line is parallel to the second direction.

Description

Technical Field

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

[0002] A solar cell is a semiconductor device that can convert light energy into electrical energy. Specifically, when a solar cell is exposed to light, the semiconductor material included in the solar cell absorbs photons and generates electron-hole pairs. The electron-hole pairs are separated under the action of the built-in electric field of the PN junction, and are respectively led out through the emitter and back field of the solar cell, and finally collected by the electrode structure.

[0003] The electrode structure generally includes a bus electrode, a collector electrode and a pad disposed on the bus electrode. Since the widths of all bus electrodes are equal, the manufacturing cost of the bus electrode is increased, and thus the manufacturing cost of the solar cell is increased. Utility Model Content

[0004] The utility model aims to provide a solar cell and a solar cell assembly, which are used to reduce the manufacturing cost of a busbar electrode, so as to reduce the manufacturing cost of the solar cell.

[0005] In order to achieve the above-mentioned purpose, in the first aspect, the utility model provides a solar cell. The solar cell includes: a battery body, a bus electrode and a collector electrode. The bus electrode is formed on the battery body, and a plurality of bus electrodes extend along a first direction and are spaced apart along a second direction, and the first direction is different from the second direction. The collector electrode is formed on the battery body, and a plurality of collector electrodes extend along the second direction and are spaced apart along the first direction. Each bus electrode intersects with a plurality of collector electrodes of the same polarity, and the collector electrodes include a positive collector electrode and a negative collector electrode. Among them, an edge negative bus electrode is provided in the edge area of ​​the battery body, and an intermediate negative bus electrode is provided in the non-edge area of ​​the battery body. On the same standard line, the width of the edge negative bus electrode is smaller than the width of the intermediate negative bus electrode, and the length extension direction of the standard line is parallel to the second direction.

[0006] Compared with the prior art, in the solar cell provided by the utility model, the width of the edge negative bus electrode is smaller than the width of the middle negative bus electrode on the same standard line. At this time, while ensuring that the edge negative bus electrode and the middle negative bus electrode are working normally, and the maximum width of all middle negative bus electrodes is basically the same or completely the same as the width of the bus electrode in the prior art, the amount of slurry used to make the edge negative bus electrode is less than the amount of slurry used in the prior art when making equal-width edge negative bus electrodes. Based on this, the production cost of the edge negative bus electrode can be reduced, thereby reducing the total production cost of all bus electrodes, and further reducing the production cost of solar cells. Furthermore, compared with the medium-width bus electrode in the prior art, the bus electrode provided by the utility model can also reduce the shielding of the battery body to improve the photoelectric conversion efficiency of the solar cell. In addition, since the length of the collector electrode connected to the edge negative bus electrode is smaller than the length of the collector electrode connected to the middle negative bus electrode, when the width of the edge negative bus electrode is smaller than the width of the middle negative bus electrode, the edge negative bus electrode can also achieve almost the same carrier collection effect as the middle negative bus electrode.

[0007] In one implementation, the solar cell further comprises: a welding pad, wherein a plurality of welding pads are arranged at intervals on the busbar electrode along the first direction. Along the first direction, the width of the middle negative busbar electrode between any two adjacent welding pads first gradually decreases and then gradually increases. Along the first direction, the width of the edge negative busbar electrode between any two adjacent welding pads first gradually decreases and then gradually increases.

[0008] In actual use, the collector electrode collects the carriers generated in the corresponding area of ​​the battery body, and the bus electrode is used to collect the carriers collected by the collector electrode intersecting with it. Then, the bus electrode transfers the collected carriers to the pad, and the pad transfers them to the welding strip connected to it. As the number of collector electrodes intersecting with the bus electrode increases, the current density borne by the bus electrode continues to increase.

[0009] Based on this, since the width of the middle negative bus electrode between any two adjacent pads along the first direction first gradually decreases and then gradually increases. It can be seen that the width of the middle negative bus electrode is the largest at the position close to the pad in the middle negative bus electrode. At this time, compared with other positions of the middle negative bus electrode, the ability of the middle negative bus electrode to bear the current density can be improved to improve the effect of the middle negative bus electrode collecting current, thereby ensuring the performance of the solar cell. Further, since the width of the edge negative bus electrode between any two adjacent pads along the first direction first gradually decreases and then gradually increases. It can be seen that the width of the edge negative bus electrode is the largest at the position close to the pad in the edge negative bus electrode. At this time, compared with other positions of the edge negative bus electrode, the ability of the edge negative bus electrode to bear the current density can be further improved to improve the effect of the edge negative bus electrode collecting current, thereby ensuring the performance of the solar cell.

[0010] In one implementation, the length of the collector electrode connected to the edge negative bus electrode is greater than half the length of the collector electrode connected to the middle negative bus electrode, and the length direction of the collector electrode is consistent with the second direction.

[0011] In one implementation, on the same standard line, the ratio of the width of the edge negative bus electrode to the width of the middle negative bus electrode is greater than 0.8 and less than 1.

[0012] In the case of adopting the above technical solution, according to the above description, the collector electrodes connected to the middle negative bus electrode are distributed on both sides of the middle negative bus electrode. In other words, the collector electrodes are overlapped on both sides of the middle negative bus electrode. However, for the edge negative bus electrode, only one side is overlapped with the collector electrode. Furthermore, since the length of the collector electrode connected to the edge negative bus electrode is greater than half the length of the collector electrode connected to the middle negative bus electrode. Therefore, on the same standard line, the ratio of the width of the edge negative bus electrode to the width of the middle negative bus electrode needs to be greater than 0.5 to facilitate the transmission of carriers. Further, in order to improve the series resistance of the edge portion, the width of the edge negative bus electrode needs to be larger. Therefore, in the utility model, on the same standard line, the ratio of the width of the edge negative bus electrode to the width of the middle negative bus electrode is greater than 0.8. Furthermore, the width of the edge negative bus electrode cannot be too large to reduce the consumption of slurry for making the edge negative bus electrode, thereby reducing the production cost of the edge negative bus electrode. Therefore, in the present invention, on the same standard line, the ratio of the width of the edge negative bus electrode to the width of the middle negative bus electrode is less than 1. In other words, for the comprehensive consideration of the carrier collection effect of the edge negative bus electrode, the production cost of the edge negative bus electrode, and the series resistance of the edge negative bus electrode, on the same standard line, the ratio of the width of the edge negative bus electrode to the width of the middle negative bus electrode is preferably greater than 0.8 and less than 1.

[0013] In one implementation, the width of the edge negative bus electrode is greater than or equal to 0.08 mm and less than or equal to 0.25 mm. The width of the middle negative bus electrode is greater than or equal to 0.08 mm and less than or equal to 0.3 mm.

[0014] When the above technical solution is adopted, since the width of the edge negative bus electrode and the width of the middle negative bus electrode are both greater than or equal to 0.08 mm, the probability of disconnection of the edge negative bus electrode and the middle negative bus electrode can be reduced or eliminated, so as to ensure that the structure of the edge negative bus electrode and the middle negative bus electrode meets the actual requirements, so as to ensure the normal operation of the solar cell. Furthermore, since the width of the edge negative bus electrode is less than or equal to 0.25 mm, and the width of the middle negative bus electrode is less than or equal to 0.3 mm. At this time, not only can the shielding of the battery body be reduced, but also the photoelectric conversion efficiency of the solar cell can be improved. At the same time, it can also ensure the ability of the edge negative bus electrode and the middle negative bus electrode to bear the current density, thereby improving the effect of collecting current.

[0015] In one implementation, the edge negative bus electrode is only provided with collector electrodes having the same polarity as the edge negative bus electrode at intervals along the first direction on one side facing the adjacent bus electrode.

[0016] In one implementation, the width of the positive collector electrode is greater than or equal to 22 micrometers and less than or equal to 140 micrometers. The width of the negative collector electrode is greater than or equal to 22 micrometers and less than or equal to 40 micrometers.

[0017] In the case of adopting the above technical solution, since the width of the positive collector electrode and the width of the negative collector electrode are both greater than or equal to 22 microns, the probability of disconnection of the positive collector electrode and the negative collector electrode can be reduced or eliminated to ensure that the structure of the positive collector electrode and the negative collector electrode meets the actual requirements to ensure the normal operation of the solar cell. Furthermore, since the width of the positive collector electrode is less than or equal to 140 microns and the width of the negative collector electrode is less than or equal to 40 microns, it can not only reduce the shielding of the battery body, but also improve the photoelectric conversion efficiency of the solar cell. At the same time, it can also ensure the collection ability of the positive collector electrode and the negative collector electrode to the carriers generated in the corresponding area of ​​the battery body.

[0018] In one implementation, the ratio of the maximum width of the intermediate negative bus electrode to the width of the positive collector electrode is greater than or equal to 2.1 and less than or equal to 13.6;

[0019] The ratio of the maximum width of the intermediate negative bus electrode to the width of the negative collector electrode is greater than or equal to 7.5 and less than or equal to 13.6;

[0020] The ratio of the minimum width of the intermediate negative bus electrode to the width of the positive collector electrode is greater than or equal to 0.55 and less than or equal to 3.64;

[0021] The ratio of the minimum width of the intermediate negative bus electrode to the width of the negative collector electrode is greater than or equal to 2 and less than or equal to 3.64.

[0022] In one implementation, the ratio of the maximum width of the edge negative bus electrode to the width of the positive collector electrode is greater than or equal to 1.79 and less than or equal to 11.36;

[0023] The ratio of the maximum width of the edge negative bus electrode to the width of the negative collector electrode is greater than or equal to 6.25 and less than or equal to 11.36;

[0024] The ratio of the minimum width of the edge negative electrode busbar electrode to the width of the positive electrode collector electrode is greater than or equal to 0.55 and less than or equal to 3.64;

[0025] The ratio of the minimum width of the edge negative electrode busbar electrode to the width of the negative electrode collector electrode is greater than or equal to 2 and less than or equal to 3.64.

[0026] In one implementation, the non-edge region of the battery body is further provided with an intermediate positive bus electrode, and along the first direction, the width of the intermediate positive bus electrode is equal at all locations. Along the second direction, the intermediate negative bus electrodes and the intermediate positive bus electrodes are alternately distributed.

[0027] In the second aspect, the utility model also provides a solar cell. The solar cell includes: a battery body, a bus electrode and a collector electrode. The bus electrode is formed on the battery body, and a plurality of bus electrodes extend along a first direction and are spaced apart along a second direction, and the first direction is different from the second direction. The collector electrode is formed on the battery body, and a plurality of collector electrodes extend along the second direction and are spaced apart along the first direction, and each bus electrode intersects with a plurality of collector electrodes with the same polarity. The collector electrodes include a positive collector electrode and a negative collector electrode. Among them, an edge positive bus electrode is provided in the edge area of ​​the battery body, and an intermediate positive bus electrode is provided in the non-edge area of ​​the battery body. On the same standard line, the width of the edge positive bus electrode is smaller than the width of the intermediate positive bus electrode, and the length extension direction of the standard line is parallel to the second direction.

[0028] Compared with the prior art, in the solar cell provided by the utility model, the width of the edge positive bus electrode is smaller than the width of the middle positive bus electrode on the same standard line. At this time, while ensuring that the edge positive bus electrode and the middle positive bus electrode are working normally, and the maximum width of all middle positive bus electrodes is basically the same or completely the same as the width of the bus electrode in the prior art, the amount of slurry used to make the edge positive bus electrode is less than the amount of slurry used in the prior art when making equal-width edge positive bus electrodes. Based on this, the production cost of the edge positive bus electrode can be reduced, thereby reducing the total production cost of all bus electrodes, and further reducing the production cost of solar cells. Furthermore, compared with the medium-width bus electrode in the prior art, the bus electrode provided by the utility model can also reduce the shielding of the battery body to improve the photoelectric conversion efficiency of the solar cell. In addition, since the length of the collector electrode connected to the edge positive bus electrode is smaller than the length of the collector electrode connected to the middle positive bus electrode, when the width of the edge positive bus electrode is smaller than the width of the middle positive bus electrode, the edge positive bus electrode can also achieve a carrier collection effect almost equivalent to that of the middle positive bus electrode.

[0029] In one implementation, on the same standard line, the ratio of the width of the edge positive bus electrode to the width of the middle positive bus electrode is greater than 0.8 and less than 1.

[0030] When the above technical solution is adopted, in the actual manufacturing process, the collector electrodes connected to the middle positive bus electrode are distributed on both sides of the middle positive bus electrode. In other words, the collector electrodes are overlapped on both sides of the middle positive bus electrode. However, for the edge positive bus electrode, only one side thereof is overlapped with the collector electrode. Furthermore, in the actual manufacturing process, since the length of the collector electrode connected to the edge positive bus electrode is greater than half the length of the collector electrode connected to the middle positive bus electrode. Therefore, on the same standard line, the ratio of the width of the edge positive bus electrode to the width of the middle positive bus electrode needs to be greater than 0.5 to facilitate the transmission of carriers. Further, in order to improve the series resistance of the edge portion, the width of the edge positive bus electrode needs to be larger. Therefore, in the utility model, on the same standard line, the ratio of the width of the edge positive bus electrode to the width of the middle positive bus electrode is greater than 0.8. Furthermore, the width of the edge positive bus electrode cannot be too large to reduce the consumption of slurry for making the edge positive bus electrode, thereby reducing the production cost of the edge positive bus electrode. Therefore, in the present invention, on the same standard line, the ratio of the width of the edge positive bus electrode to the width of the middle positive bus electrode is less than 1. In other words, for the comprehensive consideration of the carrier collection effect of the edge positive bus electrode, the production cost of the edge positive bus electrode, and the series resistance of the edge positive bus electrode, on the same standard line, the ratio of the width of the edge positive bus electrode to the width of the middle positive bus electrode is preferably greater than 0.8 and less than 1.

[0031] In a third aspect, the utility model further provides a solar cell assembly, which includes the solar cell described in the first aspect, or the solar cell assembly includes the solar cell described in the second aspect.

[0032] Compared with the prior art, the beneficial effects of the solar cell assembly provided by the present invention are the same as the beneficial effects of the solar cell described in the first aspect or the solar cell described in the second aspect, and are not described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0034] Figure 1 The schematic diagram of the partial structure of the solar cell in the embodiment of the utility model is as follows Figure 1 ;

[0035] Figure 2 The schematic diagram of the partial structure of the solar cell in the embodiment of the utility model is as follows Figure 2 .

[0036] Reference numerals:

[0037] 1-battery body, 2-bus electrode, 20-edge negative bus electrode, 21-middle negative bus electrode, 22-middle positive bus electrode, 3-collecting electrode, 4-welding pad. DETAILED DESCRIPTION

[0038] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0039] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0040] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined. The meaning of "several" is one or more, unless otherwise clearly and specifically defined.

[0041] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0042] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0043] In order to solve the above technical problems, in the first aspect, an embodiment of the utility model provides a solar cell. The solar cell includes: a battery body 1, a bus electrode 2 and a collector electrode 3. The bus electrode 2 is formed on the battery body 1, and a plurality of bus electrodes 2 extend along a first direction and are spaced apart along a second direction, and the first direction is different from the second direction. The collector electrode 3 is formed on the battery body 1, and a plurality of collector electrodes 3 extend along the second direction and are spaced apart along the first direction. Each bus electrode 2 intersects with a plurality of collector electrodes 3 of the same polarity, and the collector electrode 3 includes a positive collector electrode and a negative collector electrode. Among them, an edge negative bus electrode 20 is provided in the edge area of ​​the battery body 1, and an intermediate negative bus electrode 21 is provided in the non-edge area of ​​the battery body 1. On the same standard line M, the width of the edge negative bus electrode 20 is less than the width of the intermediate negative bus electrode 21, and the length extension direction of the standard line M is parallel to the second direction. It should be noted that the edge bus electrode refers to: a bus electrode that is closest to the edge of the battery cell body 1 in the second direction, and the edge bus electrode can be positive or negative.

[0044] The structure and specifications of the battery body can be set according to actual conditions and are not specifically limited here. Furthermore, the first direction and the second direction can be any two directions parallel to the surface of the battery body and different from each other. Figure 1 , the first direction A and the second direction B are orthogonal.

[0045] See also Figure 1 In the solar cell provided by the embodiment of the utility model, on the same standard line M, the width of the edge negative bus electrode 20 is smaller than the width of the middle negative bus electrode 21. At this time, while ensuring that the edge negative bus electrode 20 and the middle negative bus electrode 21 are working normally, and the maximum width of all the middle negative bus electrodes 21 is basically the same or completely the same as the width of the bus electrode in the prior art, the amount of slurry used to make the edge negative bus electrode 20 is less than the amount of slurry used in the prior art when making equal-width edge negative bus electrodes. Based on this, the production cost of the edge negative bus electrode 20 can be reduced, thereby reducing the total production cost of all bus electrodes, and further reducing the production cost of the solar cell. Furthermore, compared with the medium-width bus electrode in the prior art, the bus electrode provided by the embodiment of the utility model can also reduce the shielding of the battery body 1 to improve the photoelectric conversion efficiency of the solar cell. In addition, since the length of the collector electrode connected to the edge negative bus electrode is smaller than the length of the collector electrode connected to the middle negative bus electrode, when the width of the edge negative bus electrode is smaller than the width of the middle negative bus electrode, the edge negative bus electrode can also achieve almost the same carrier collection effect as the middle negative bus electrode.

[0046] As a possible implementation, see Figure 1 and Figure 2 The solar cell further comprises: a welding pad 4, wherein a plurality of welding pads 4 are arranged at intervals on the bus electrode 2 along the first direction. Along the first direction A, the width of the middle negative bus electrode 21 between any two adjacent welding pads 4 first gradually decreases and then gradually increases. Along the first direction A, the width of the edge negative bus electrode 20 between any two adjacent welding pads 4 first gradually decreases and then gradually increases.

[0047] In actual use, the collector electrode 3 collects the carriers generated in the corresponding area of ​​the battery body 1, and the bus electrode 2 is used to collect the carriers collected by the collector electrode 3 intersecting with it. Then, the bus electrode transmits the collected carriers to the pad 4, and the pad 4 transmits them to the welding strip connected to it. As the number of collector electrodes 3 intersecting with the bus electrode 2 increases, the current density borne by the bus electrode continues to increase.

[0048] Based on this, since the width of the middle negative bus electrode 21 between any two adjacent pads 4 along the first direction A first gradually decreases and then gradually increases. It can be seen that the width of the middle negative bus electrode 21 is the largest at the position close to the pad 4 in the middle negative bus electrode 21. At this time, compared with other positions of the middle negative bus electrode 21, the ability of the middle negative bus electrode 21 to bear the current density can be improved to improve the effect of the middle negative bus electrode 21 collecting current, thereby ensuring the performance of the solar cell. Further, since the width of the edge negative bus electrode 20 between any two adjacent pads 4 along the first direction A first gradually decreases and then gradually increases. It can be seen that the width of the edge negative bus electrode 20 is the largest at the position close to the pad 4 in the edge negative bus electrode 20. At this time, compared with other positions of the edge negative bus electrode 20, the ability of the edge negative bus electrode 20 to bear the current density can be further improved to improve the effect of the edge negative bus electrode 20 collecting current, thereby ensuring the performance of the solar cell.

[0049] For example, see Figure 1 , along the first direction A, from the center point between the two pads 4 to any adjacent pad 4, the width of the middle negative bus electrode 21 gradually increases. Similarly, along the first direction, from the center point between the two pads 4 to any adjacent pad 4, the width of the edge negative bus electrode 20 gradually increases.

[0050] As a possible implementation, see Figure 1 and Figure 2, the edge negative bus electrode 20 is provided with collector electrodes 3 having the same polarity as the edge negative bus electrode 20 at intervals along the first direction only on one side facing the adjacent bus electrode. It should be noted that in other embodiments, the edge negative bus electrode 20 is further provided with a collector electrode 3 having a very short length (e.g., within 0.2 mm) in the area facing the edge of the battery cell body.

[0051] As a possible implementation, see Figure 2 The length L1 of the collector electrode 3 connected to the edge negative bus electrode 20 is greater than half the length L2 of the collector electrode 3 connected to the middle negative bus electrode 21, and the length direction of the collector electrode 3 is consistent with the second direction.

[0052] As a possible implementation, on the same standard line, the ratio of the width of the edge negative bus electrode to the width of the middle negative bus electrode is greater than 0.8 and less than 1. For example, the ratio may be 0.81, 0.85, 0.9, 0.92, 0.95, 0.98, etc.

[0053] According to the above description, the collector electrodes connected to the middle negative bus electrode are distributed on both sides of the middle negative bus electrode. In other words, the collector electrodes are overlapped on both sides of the middle negative bus electrode. However, for the edge negative bus electrode, only one side is overlapped with the collector electrode. In combination with practice, it can be known that the number of collector electrodes overlapped on the bus electrode is proportional to the width of the bus electrode, so as to facilitate better busing of the bus electrode. Further, since the length of the collector electrode connected to the edge negative bus electrode is greater than half the length of the collector electrode connected to the middle negative bus electrode. Therefore, in the embodiment of the utility model, on the same standard line, the ratio of the width of the edge negative bus electrode to the width of the middle negative bus electrode needs to be greater than 0.5, so as to facilitate the transmission of carriers. Further, in order to improve the series resistance of the edge part, the width of the edge negative bus electrode needs to be larger. Therefore, in the embodiment of the utility model, on the same standard line, the ratio of the width of the edge negative bus electrode to the width of the middle negative bus electrode is greater than 0.8. Furthermore, the width of the edge negative bus electrode cannot be too large to reduce the consumption of slurry for making the edge negative bus electrode, thereby reducing the production cost of the edge negative bus electrode. Therefore, on the same standard line, the ratio of the width of the edge negative bus electrode to the width of the middle negative bus electrode is less than 1. In other words, for the comprehensive consideration of the carrier collection effect of the edge negative bus electrode, the production cost of the edge negative bus electrode, and the series resistance of the edge negative bus electrode, the ratio of the width of the edge negative bus electrode to the width of the middle negative bus electrode on the same standard line is preferably greater than 0.8 and less than 1.

[0054] Exemplarily, along the first direction, four positions are selected between two adjacent pads. The following describes the ratio of the width of the edge negative bus electrode to the width of the middle negative bus electrode on the same standard line at the above four positions using a possible situation as an example. It should be understood that the following description is only for understanding and is not intended to be specifically limited.

[0055] See also Figure 2 , the position closest to any pad 4 is position 1 (in Figure 2 A standard line is formed at position 1 along the second direction, and the ratio of the width of the edge negative bus electrode 20 to the width of the middle negative bus electrode 21 is 0.846.

[0056] Define the center point of two adjacent pads 4 as position 2, and take the center point of position 1 and position 2 as position 3 (in Figure 2 A standard line is formed along the second direction at position 3, where the ratio of the width of the edge negative bus electrode 20 to the width of the middle negative bus electrode 21 is 0.882.

[0057] Select a point between position 1 and position 3 as position 4 (in Figure 2 The position 4 is close to the position 3, and a standard line is formed along the second direction at the position 4. At this time, the ratio of the width of the edge negative bus electrode 20 to the width of the middle negative bus electrode 21 is 0.850.

[0058] Select a point between position 2 and position 3 as position 5 (in Figure 2 The position 5 is close to the position 3, and a standard line is formed along the second direction at the position 4. At this time, the ratio of the width of the edge negative bus electrode 20 to the width of the middle negative bus electrode 21 is 0.867.

[0059] As a possible implementation, the width of the above-mentioned edge negative bus electrode is greater than or equal to 0.08 mm and less than or equal to 0.25 mm. The width of the middle negative bus electrode is greater than or equal to 0.08 mm and less than or equal to 0.3 mm. Exemplarily, the width of the edge negative bus electrode can be 0.08 mm, 0.10 mm, 0.15 mm, 0.18 mm, 0.20 mm, 0.22 mm, 0.23 mm or 0.25 mm, etc. The width of the middle negative bus electrode can be 0.08 mm, 0.10 mm, 0.15 mm, 0.18 mm, 0.20 mm, 0.22 mm, 0.23 mm, 0.25 mm, 0.27 mm or 0.3 mm, etc.

[0060] When the above technical solution is adopted, since the width of the edge negative bus electrode and the width of the middle negative bus electrode are both greater than or equal to 0.08 mm, the probability of disconnection of the edge negative bus electrode and the middle negative bus electrode can be reduced or eliminated, so as to ensure that the structure of the edge negative bus electrode and the middle negative bus electrode meets the actual requirements, so as to ensure the normal operation of the solar cell. Furthermore, since the width of the edge negative bus electrode is less than or equal to 0.25 mm, and the width of the middle negative bus electrode is less than or equal to 0.3 mm. At this time, not only can the shielding of the battery body be reduced, but also the photoelectric conversion efficiency of the solar cell can be improved. At the same time, it can also ensure the ability of the edge negative bus electrode and the middle negative bus electrode to bear the current density, thereby improving the effect of collecting current.

[0061] As a possible implementation, the width of the positive collector electrode is greater than or equal to 22 microns and less than or equal to 140 microns. Exemplarily, the width of the positive collector electrode may be 22 microns, 25 microns, 30 microns, 50 microns, 73 microns, 82 microns, 90 microns, 100 microns, 110 microns, 120 microns, 130 microns or 140 microns, etc. Preferably, the width of the positive collector electrode is greater than or equal to 100 microns and less than or equal to 140 microns.

[0062] As a possible implementation, the width of the negative collector electrode is greater than or equal to 22 microns and less than or equal to 40 microns. Exemplarily, the width of the negative collector electrode may be 22 microns, 25 microns, 28 microns, 30 microns, 32 microns, 33 microns, 35 microns, 38 microns or 40 microns, etc. Preferably, the width of the negative collector electrode is greater than or equal to 35 microns and less than or equal to 40 microns.

[0063] In the case of adopting the above technical solution, since the width of the positive collector electrode and the width of the negative collector electrode are both greater than or equal to 22 microns, the probability of disconnection of the positive collector electrode and the negative collector electrode can be reduced or eliminated to ensure that the structure of the positive collector electrode and the negative collector electrode meets the actual requirements to ensure the normal operation of the solar cell. Furthermore, since the width of the positive collector electrode is less than or equal to 140 microns and the width of the negative collector electrode is less than or equal to 40 microns, it can not only reduce the shielding of the battery body, but also improve the photoelectric conversion efficiency of the solar cell. At the same time, it can also ensure the collection ability of the positive collector electrode and the negative collector electrode to the carriers generated in the corresponding area of ​​the battery body.

[0064] As a possible implementation, the ratio of the maximum width of the intermediate negative bus electrode to the width of the positive collector electrode is greater than or equal to 2.1 and less than or equal to 13.6. For example, the ratio may be 2.1, 2.5, 2.9, 3.0, 3.5, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 or 13.6. Exemplarily, the maximum width of the intermediate negative bus electrode is 0.3 mm. The width of the positive collector electrode is greater than or equal to 22 microns and less than or equal to 140 microns.

[0065] The ratio of the maximum width of the intermediate negative bus electrode to the width of the negative collector electrode is greater than or equal to 7.5 and less than or equal to 13.6. For example, the ratio may be 7.5, 8, 9, 10, 11, 12, 13 or 13.6. Exemplarily, the maximum width of the intermediate negative bus electrode is 0.3 mm. The width of the negative collector electrode is greater than or equal to 22 microns and less than or equal to 40 microns.

[0066] The ratio of the minimum width of the intermediate negative bus electrode to the width of the positive collector electrode is greater than or equal to 0.55 and less than or equal to 3.64. For example, the ratio can be 0.55, 0.7, 1, 1.5, 2, 2.4, 3, 3.2, 3.37, 3.5, 3.6 or 3.64. Exemplarily, the minimum width of the intermediate negative bus electrode is 0.08 mm. The width of the positive collector electrode is greater than or equal to 22 microns and less than or equal to 140 microns.

[0067] The ratio of the minimum width of the intermediate negative bus electrode to the width of the negative collector electrode is greater than or equal to 2 and less than or equal to 3.64. For example, the ratio may be 2, 2.4, 3, 3.2, 3.37, 3.5, 3.6 or 3.64. Exemplarily, the minimum width of the intermediate negative bus electrode is 0.08 mm. The width of the negative collector electrode is greater than or equal to 22 microns and less than or equal to 40 microns.

[0068] As a possible implementation, the ratio of the maximum width of the edge negative bus electrode to the width of the positive collector electrode is greater than or equal to 1.79 and less than or equal to 11.36. For example, the ratio may be 1.79, 2.0, 2.5, 2.9, 3.0, 3.5, 4, 5, 6, 7, 8, 9, 10, 11, 11.3 or 11.36. Exemplarily, the maximum width of the edge negative bus electrode is 0.25 mm. The width of the positive collector electrode is greater than or equal to 22 microns and less than or equal to 140 microns.

[0069] The ratio of the maximum width of the edge negative bus electrode to the width of the negative collector electrode is greater than or equal to 6.25 and less than or equal to 11.36. For example, the ratio can be 6.25, 6.5, 7, 8, 9, 10, 11, 11.3 or 11.36. Exemplarily, the maximum width of the edge negative bus electrode is 0.25 mm. The width of the negative collector electrode is greater than or equal to 22 microns and less than or equal to 40 microns.

[0070] The ratio of the minimum width of the edge negative bus electrode to the width of the positive collector electrode is greater than or equal to 0.55 and less than or equal to 3.64; for example, the ratio can be 0.55, 0.7, 1, 1.5, 2, 2.4, 3, 3.2, 3.37, 3.5, 3.6 or 3.64. Exemplarily, the minimum width of the edge negative bus electrode is 0.08 mm. The width of the positive collector electrode is greater than or equal to 22 microns and less than or equal to 140 microns.

[0071] The ratio of the minimum width of the edge negative bus electrode to the width of the negative collector electrode is greater than or equal to 2 and less than or equal to 3.64. For example, the ratio can be 2, 2.4, 3, 3.2, 3.37, 3.5, 3.6 or 3.64. Exemplarily, the minimum width of the edge negative bus electrode is 0.08 mm. The width of the negative collector electrode is greater than or equal to 22 microns and less than or equal to 40 microns.

[0072] As a possible implementation, see Figure 1 The non-edge area of ​​the battery body 1 is also provided with an intermediate positive bus electrode 22, and the width of the intermediate positive bus electrode 22 is equal at all locations along the first direction A. Along the second direction, the intermediate negative bus electrodes 21 and the intermediate positive bus electrodes 22 are alternately distributed.

[0073] As a possible implementation, the solar cell may be a back contact cell or other types of cells, which are not specifically limited here.

[0074] Since the edge negative bus electrode and the middle negative bus electrode (collectively referred to as the negative bus electrode for ease of description) are usually made of silver paste, the unit price of silver is relatively high. Therefore, when the edge negative bus electrode and the middle negative bus electrode provided by the embodiment of the utility model are used, the production cost of the bus electrode can be reduced while ensuring the performance of the negative bus electrode, thereby reducing the production cost of the solar cell. The above-mentioned positive bus electrode is generally made of aluminum paste.

[0075] In the second aspect, the embodiment of the utility model also provides a solar cell. The solar cell includes: a battery body, a bus electrode and a collector electrode. The bus electrode is formed on the battery body, and a plurality of bus electrodes extend along a first direction and are spaced apart along a second direction, and the first direction is different from the second direction. The collector electrode is formed on the battery body, and a plurality of collector electrodes extend along the second direction and are spaced apart along the first direction, and each bus electrode intersects with a plurality of collector electrodes of the same polarity. The collector electrodes include a positive collector electrode and a negative collector electrode. Among them, an edge positive bus electrode is provided in the edge area of ​​the battery body, and an intermediate positive bus electrode is provided in the non-edge area of ​​the battery body. On the same standard line, the width of the edge positive bus electrode is smaller than the width of the intermediate positive bus electrode, and the length extension direction of the standard line is parallel to the second direction.

[0076] In the solar cell provided by the embodiment of the utility model, the width of the edge positive bus electrode is smaller than the width of the middle positive bus electrode on the same standard line. At this time, while ensuring that the edge positive bus electrode and the middle positive bus electrode are working normally, and the maximum width of all middle positive bus electrodes is basically the same or completely the same as the width of the bus electrode in the prior art, the amount of slurry used to make the edge positive bus electrode is less than the amount of slurry used in the prior art when making equal-width edge positive bus electrodes. Based on this, the production cost of the edge positive bus electrode can be reduced, thereby reducing the total production cost of all bus electrodes, and further reducing the production cost of the solar cell. Furthermore, compared with the medium-width bus electrode in the prior art, the bus electrode provided by the embodiment of the utility model can also reduce the shielding of the battery body to improve the photoelectric conversion efficiency of the solar cell. In addition, since the length of the collector electrode connected to the edge positive bus electrode is smaller than the length of the collector electrode connected to the middle positive bus electrode, when the width of the edge positive bus electrode is smaller than the width of the middle positive bus electrode, the edge positive bus electrode can also achieve a carrier collection effect almost equivalent to that of the middle positive bus electrode.

[0077] As a possible implementation, on the same standard line, the ratio of the width of the edge positive bus electrode to the width of the middle positive bus electrode is greater than 0.8 and less than 1. For example, the ratio may be 0.81, 0.85, 0.9, 0.92, 0.95, 0.98, etc.

[0078] In the actual manufacturing process, the collector electrodes connected to the middle positive bus electrode are distributed on both sides of the middle positive bus electrode. In other words, the collector electrodes are overlapped on both sides of the middle positive bus electrode. However, for the edge positive bus electrode, only one side is overlapped with the collector electrode. Further, in the actual manufacturing process, since the length of the collector electrode connected to the edge positive bus electrode is greater than half the length of the collector electrode connected to the middle positive bus electrode. Therefore, on the same standard line, the ratio of the width of the edge positive bus electrode to the width of the middle positive bus electrode needs to be greater than 0.5 to facilitate the transmission of carriers. Further, in order to improve the series resistance of the edge part, the width of the edge positive bus electrode needs to be larger. Therefore, in the utility model, on the same standard line, the ratio of the width of the edge positive bus electrode to the width of the middle positive bus electrode is greater than 0.8. Further, the width of the edge positive bus electrode cannot be too large to reduce the consumption of slurry for making the edge positive bus electrode, thereby reducing the production cost of the edge positive bus electrode. Therefore, in the present invention, on the same standard line, the ratio of the width of the edge positive bus electrode to the width of the middle positive bus electrode is less than 1. In other words, due to the comprehensive consideration of the carrier collection effect of the edge positive bus electrode, the manufacturing cost of the edge positive bus electrode, and the series resistance of the edge positive bus electrode, on the same standard line, the ratio of the width of the edge positive bus electrode to the width of the middle positive bus electrode is preferably greater than 0.8 and less than 1.

[0079] In a third aspect, the embodiment of the utility model further provides a solar cell assembly. The solar cell assembly includes the solar cell described in the first aspect, or the solar cell assembly includes the solar cell described in the second aspect.

[0080] The beneficial effects of the solar cell assembly provided by the embodiment of the utility model are the same as the beneficial effects of the solar cell described in the first aspect or the solar cell described in the second aspect, and are not described in detail here.

[0081] In the description of the above embodiments, specific features, structures, materials or characteristics may be combined in a suitable manner in any one or more embodiments or examples.

[0082] The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the utility model, which should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. A solar cell, characterized in that: include: Battery body; A bus electrode formed on the battery body; The plurality of bus electrodes extend along a first direction and are spaced apart along a second direction; the first direction is different from the second direction; A collector electrode is formed on the battery body; a plurality of the collector electrodes extend along the second direction and are spaced apart along the first direction; each of the bus electrodes intersects with a plurality of the collector electrodes with the same polarity; the collector electrodes include a positive collector electrode and a negative collector electrode; Among them, an edge negative bus electrode is arranged in the edge area of ​​the battery body, and an intermediate negative bus electrode is arranged in the non-edge area of ​​the battery body; on the same standard line, the width of the edge negative bus electrode is smaller than the width of the intermediate negative bus electrode; the length extension direction of the standard line is parallel to the second direction.

2. The solar cell according to claim 1, characterized in that: The solar cell further comprises: a soldering pad, a plurality of the soldering pads being arranged on the bus electrode at intervals along a first direction; Along the first direction, the width of the middle negative bus electrode between any two adjacent pads first gradually decreases and then gradually increases; Along the first direction, the width of the edge negative bus electrode between any two adjacent pads first gradually decreases and then gradually increases.

3. The solar cell according to claim 1 or 2, characterized in that: The length of the collector electrode connected to the edge negative bus electrode is greater than half the length of the collector electrode connected to the middle negative bus electrode, and the length direction of the collector electrode is consistent with the second direction.

4. The solar cell according to claim 1, characterized in that On the same standard line, the ratio of the width of the edge negative bus electrode to the width of the middle negative bus electrode is greater than 0.8 and less than 1.

5. The solar cell according to claim 1 or 2, characterized in that: The width of the edge negative bus electrode is greater than or equal to 0.08 mm and less than or equal to 0.25 mm; The width of the intermediate negative bus electrode is greater than or equal to 0.08 mm and less than or equal to 0.3 mm.

6. The solar cell according to claim 1, characterized in that The collector electrodes having the same polarity as the edge negative bus electrode are arranged at intervals along the first direction only on one side of the edge negative bus electrode facing the adjacent bus electrode.

7. The solar cell according to claim 1, characterized in that The width of the positive current collector electrode is greater than or equal to 22 microns and less than or equal to 140 microns; The width of the negative collector electrode is greater than or equal to 22 micrometers and less than or equal to 40 micrometers.

8. The solar cell according to claim 1, characterized in that The ratio of the maximum width of the intermediate negative electrode busbar electrode to the width of the positive electrode collector electrode is greater than or equal to 2.1 and less than or equal to 13.6; The ratio of the maximum width of the intermediate negative bus electrode to the width of the negative collector electrode is greater than or equal to 7.5 and less than or equal to 13.6; The ratio of the minimum width of the intermediate negative electrode busbar electrode to the width of the positive electrode collector electrode is greater than or equal to 0.55 and less than or equal to 3.64; The ratio of the minimum width of the intermediate negative electrode bus electrode to the width of the negative electrode collector electrode is greater than or equal to 2 and less than or equal to 3.

64.

9. The solar cell according to claim 1, characterized in that: The ratio of the maximum width of the edge negative electrode busbar electrode to the width of the positive electrode collector electrode is greater than or equal to 1.79 and less than or equal to 11.36; The ratio of the maximum width of the edge negative bus electrode to the width of the negative collector electrode is greater than or equal to 6.25 and less than or equal to 11.36; The ratio of the minimum width of the edge negative electrode busbar electrode to the width of the positive electrode collector electrode is greater than or equal to 0.55 and less than or equal to 3.64; The ratio of the minimum width of the edge negative electrode bus electrode to the width of the negative electrode collector electrode is greater than or equal to 2 and less than or equal to 3.

64.

10. The solar cell according to claim 1, characterized in that: An intermediate positive bus electrode is also provided in the non-edge area of ​​the battery body; along the first direction, the width of the intermediate positive bus electrode is equal at all locations; along the second direction, the intermediate negative bus electrode and the intermediate positive bus electrode are alternately distributed.

11. A solar cell, characterized in that: include: Battery body; A bus electrode formed on the battery body; The plurality of bus electrodes extend along a first direction and are spaced apart along a second direction; the first direction is different from the second direction; A collector electrode is formed on the battery body; a plurality of the collector electrodes extend along the second direction and are spaced apart along the first direction; each of the bus electrodes intersects with a plurality of the collector electrodes with the same polarity; the collector electrodes include a positive collector electrode and a negative collector electrode; Among them, an edge positive bus electrode is arranged in the edge area of ​​the battery body, and an intermediate positive bus electrode is arranged in the non-edge area of ​​the battery body; on the same standard line, the width of the edge positive bus electrode is smaller than the width of the intermediate positive bus electrode; the length extension direction of the standard line is parallel to the second direction.

12. The solar cell according to claim 11, characterized in that: On the same standard line, the ratio of the width of the edge positive bus electrode to the width of the middle positive bus electrode is greater than 0.8 and less than 1.

13. A solar cell module, characterized in that: The solar cell assembly comprises the solar cell according to any one of claims 1 to 10; or, the solar cell assembly comprises the solar cell according to claim 11 or 12.

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