Solar cell and solar cell module
By unequally dividing the solar cell units and adjusting the electrode pattern, the circuit mismatch problem of the four-segment module was solved, improving the power generation efficiency and stability of the battery module and reducing power loss and hot spot risk.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-29
- Publication Date
- 2026-04-14
AI Technical Summary
The four-segment solar cell module has a circuit mismatch problem, which leads to uneven power generation and increased power loss.
By adopting an unequal division method, the width of the battery cell and the distribution of the electrode pattern are adjusted so that the area of the battery cell near the edge is smaller. The electrode patterns of adjacent battery cells are isolated by segmentation areas, thereby improving current matching.
This effectively solved the circuit mismatch problem, improved the power generation efficiency and stability of the solar cell module, and reduced power loss and hot spot risk.
Smart Images
Figure CN224124500U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of photovoltaic technology, specifically to solar cells and solar cell modules. Background Technology
[0002] Currently, mainstream solar cell modules use half-cell solar cells. A half-cell solar cell is obtained by evenly cutting a full solar cell along its middle. Compared to a single full solar cell, connecting two half-cell solar cells in series reduces the photocurrent in the circuit to half that of a full solar cell. This is because the power generation area of a half-cell solar cell is half that of a full solar cell, therefore the power generation current of each half-cell solar cell is half the current (I) of the full solar cell. Since the current in a series circuit is equal, the current in the circuit after connecting two half-cell solar cells in series is I / 2. The power loss P of the solar cell module... 损 =I 2 Therefore, reducing the current flowing through the solar cell module can reduce power loss and lower the risk of hot spots.
[0003] Besides the mainstream two-segment design, four-segment designs have also emerged in related technologies. Four-segment solar cell modules can reduce current transmission losses in solar cell strings, decrease the probability of hot spot effects, improve module reliability and stability, and extend module lifespan. However, four-segment solar cell modules suffer from circuit mismatch issues. Utility Model Content
[0004] This disclosure provides a solar cell and a solar cell module that solves the circuit mismatch problem of multi-segment solar cell modules.
[0005] According to another aspect of this disclosure, a solar cell is provided, having a first edge and a second edge opposite each other in a first direction, and a third edge and a fourth edge opposite each other in a second direction, the first direction being perpendicular to the second direction. The solar cell has three segmented regions spaced apart along the first direction, each segmented region extending from the third edge to the fourth edge along the second direction, with the center line of the three segmented regions serving as the boundary. The solar cell includes four cell units connected sequentially along the first direction, wherein, in the first direction, the width of the two cell units containing the first edge and the second edge is 1.5 mm to 5 mm smaller than the width of the other cell units.
[0006] In some implementations, in a first direction, the widths of two battery cells including the first edge and the second edge are equal, and the widths of other battery cells are equal.
[0007] In some embodiments, each battery cell has an electrode pattern on both its front and back surfaces, or only on its back surface. The area between the electrode patterns of adjacent battery cells that does not have an electrode pattern is constructed as a segmented area. In a first direction, the width of the electrode patterns of two battery cells, including a first edge and a second edge, is smaller than the width of the electrode patterns of other battery cells.
[0008] In some embodiments, in the first direction, the width of the two battery cells adjacent to the first edge and the second edge is 1.5mm-2mm smaller than the width of the other battery cells, or 2mm-2.5mm smaller, or 2.5mm-3mm smaller, or 3mm-3.5mm smaller, or 3.5mm-4mm smaller, or 4mm-4.5mm smaller, or 4.5mm-5mm smaller.
[0009] In some implementations, in the first direction, the width of the two battery cells including the first edge and the second edge is greater than or equal to 44.9 mm and less than or equal to 49.9 mm, and the width of the other solar cells is greater than or equal to 46.75 mm and less than or equal to 51.75 mm.
[0010] In some implementations, in the first direction, the width of the two battery cells including the first edge and the second edge is greater than or equal to 51.5 mm and less than or equal to 56.5 mm, and the width of the other solar cells is greater than or equal to 53.5 mm and less than or equal to 58.5 mm.
[0011] In some implementations, the width of the segmented region is 0.8mm-1.2mm.
[0012] According to another aspect of this disclosure, a solar cell module is provided, the module comprising all cell cells obtained by cutting the aforementioned solar cell along a slab region.
[0013] This disclosure employs an unequal division method, where the area of the cell unit near the edge of the solar cell is smaller than that of other cell units, thus enabling current matching of the cell units. Attached Figure Description
[0014] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below.
[0015] Obviously, the accompanying drawings described below are some embodiments of this utility model. For those skilled in the art, they can obtain [further details] from these drawings without any creative effort.
[0016] Other attached figures.
[0017] Figure 1A schematic diagram of one side of a solar cell is shown in some examples of this disclosure.
[0018] Figure 2 It shows Figure 1 A magnified view of one end of the segmented region of the solar cell shown. Detailed Implementation
[0019] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.
[0020] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.
[0021] In this application, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "inner," "outer," "middle," "vertical," "horizontal," "lateral," and "longitudinal" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing the present invention and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.
[0022] Furthermore, in addition to indicating direction or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this utility model according to the specific circumstances.
[0023] Furthermore, the terms "installation," "setup," "equipped with," "connection," "linking," and "socketing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this utility model based on the specific circumstances.
[0024] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.
[0025] The inventors of this application have discovered that the cause of circuit mismatch and EL brightness differences is the uneven power generation of the four segments. Although the existing four segments are geometrically equal, in reality, the power generation of the four segments is not equal; rather, the two smaller segments at the edges generate more power than the two smaller segments in the middle. The inventors have discovered the following reasons:
[0026] (1) The electrical properties of the monocrystalline silicon wafers used to prepare solar cells are unevenly distributed, resulting in unequal power of each small wafer after geometric division. The silicon wafers used to prepare solar cells are obtained by cutting monocrystalline silicon rods. Monocrystalline silicon rods are produced by crystal pulling, and the process itself will cause the minority carrier lifetime in the middle of the monocrystalline silicon rod to be shorter than that at the edge.
[0027] (2) The uneven distribution of electrical properties in the solar cell fabrication process leads to unequal power distribution among the individual cells after geometric division. During cell fabrication, slight variations in process conditions, such as non-uniform phosphorus diffusion in the diffusion process and differences in the contact resistance between the electrode and the silicon wafer during electrode fabrication, result in differences in minority carrier lifetime, series resistance, and other electrical parameters across different regions of the solar cell. The diffusion process also causes the sheet resistance in the middle to be higher than that at the edges. The minority carrier lifetime at the edges may be relatively longer, or the series resistance relatively smaller, allowing the two smaller cells at the edges to collect and transport photogenerated carriers more effectively under the same illumination conditions, thus resulting in higher output power.
[0028] (3) The impact of the slitting process on the solar cells. The slitting operation of the solar cells will destroy the crystalline silicon integrity of the monocrystalline silicon and introduce a large number of defects on the cut surface. These defects will become recombination centers, resulting in power loss of the solar cells. The two middle cells each have two cut edges, while the two edge cells each have one cut edge. Therefore, the power loss of the two middle cells is greater than that of the two edge cells.
[0029] According to one aspect of this disclosure, a solar cell 10 is provided.
[0030] Figure 1 A solar cell 10 according to some exemplary embodiments of the present disclosure is shown. The solar cell 10 has a first edge 11 and a second edge 12 opposite each other in a first direction D1, and a third edge 13 and a fourth edge 14 opposite each other in a second direction D2, the first direction D1 being perpendicular to the second direction D2. The first edge 11, the second edge 12, the third edge 13, and the fourth edge 14 constitute the four sides of a square or rectangular solar cell.
[0031] For example, the solar cell 10 can be a monocrystalline silicon or polycrystalline silicon solar cell, or it can be a perovskite crystalline silicon tandem solar cell.
[0032] The solar cell 10 has three segmented regions 15 spaced apart along a first direction D1. Each segmented region 15 extends from the third edge 13 to the fourth edge 14 of the solar cell 10 along a second direction D2. The center line L of the three segmented regions 15 serves as the boundary. The solar cell 10 includes four battery cells connected sequentially along the first direction D1. In the first direction D1, the width of the two battery cells containing the first edge 11 and the second edge 12 is smaller than the width of the other battery cells.
[0033] Specifically, the slicing region 15 is the region used to slice the solar cell 10. The slicing region 15 may not have an electrode pattern. Figure 1 In the illustrated embodiment, the center line L of the three segmented regions 15 divides the solar cell 10 into four cell units: the first cell unit 161, the second cell unit 162, the third cell unit 163, and the fourth cell unit 164. The solar cell 10 can be divided into four segments along the segmented regions 15.
[0034] The centerline L of segmented region 15 is the line connecting the midpoints of the width of segmented region 15. The centerline L extends along the second direction D2, and the two long sides of segmented region 15 are equidistant from the centerline L.
[0035] Please combine Figure 1 and Figure 2 Each battery cell has an electrode pattern 17 on both the front and back surfaces, or only on the back surface. The area between the electrode patterns 17 of adjacent battery cells that does not have an electrode pattern is constructed as a segmented area 15.
[0036] The front surface of a solar cell or cell unit can be the surface facing solar radiation during operation, while the back surface can be the surface facing away from solar radiation during operation. Electrode patterns of different polarities in the solar cell 10 can be respectively disposed on the front and back surfaces of the cell; for example, the positive electrode pattern can be disposed on the front surface, and the negative electrode pattern can be disposed on the back surface. Exemplarily, the solar cell can be a TOPCon (tunneling oxide passivated contact), HJT (heterojunction), or PERC (emitter and back passivated cell). Electrode patterns of different polarities in the solar cell can also be simultaneously disposed on the back surface of the solar cell; exemplarily, the solar cell can be an IBC (interdigitated back contact) cell.
[0037] Since the solar cell 10 is divided into three cell units by the segmentation region 15, each cell unit has an electrode pattern 17, and the electrode patterns 17 of adjacent cell units are separated by the segmentation region 15, the area between the electrode patterns 17 of adjacent cell units where no electrode pattern is provided is constructed as the segmentation region 15.
[0038] For example, such as Figure 1 As shown, the first battery unit 161 is a battery unit including the first edge 11, and the fourth battery unit 164 is a battery unit including the second edge 12. The width W1 of the first battery unit 161 and the width W4 of the fourth battery unit 164 are both smaller than the width W2 of the second battery unit 162 and the width W3 of the third battery unit 163.
[0039] For example, in the first direction D1, the width W1 of the first battery cell 161 and the width W4 of the fourth battery cell 164 are equal, and the width W2 of the second battery cell 162 and the width W3 of the third battery cell 163 are equal.
[0040] In the first direction D1, the width of the electrode pattern of the two battery cells containing the first edge 11 and the second edge 12 is smaller than the width of the electrode pattern of the other battery cells. The other battery cells are battery cells other than the two battery cells containing the first edge 11 and the second edge 12. For example, as... Figure 1 As shown, the width of the electrode patterns on the first battery cell 161 and the fourth battery cell 164 is smaller than the width of the electrode patterns on the second battery cell 162 and the third battery cell 163. The electrode patterns of the second battery cell 162 and the third battery cell 163 have a wider width, so that the electrode patterns of the second battery cell 162 and the third battery cell 163 can cover more of the edge of the corresponding battery cell, thereby improving the carrier collection efficiency at the edge of the battery cell.
[0041] Specifically, in the first direction D1, the width of the two battery cells containing the first edge 11 and the second edge 12 is 1.5mm-5mm smaller than the width of the other battery cells. Further, in the first direction D1, the width of the two battery cells adjacent to the first edge 11 and the second edge 12 is 1.5mm-2mm smaller, or 2mm-2.5mm smaller, or 2.5mm-3mm smaller, or 3mm-3.5mm smaller, or 3.5mm-4mm smaller, or 4mm-4.5mm smaller, or 4.5mm-5mm smaller than the width of the other battery cells. This reasonable width difference between battery cells located at different positions within the entire cell reduces the current difference between the two battery cells containing the first edge 11 and the second edge 12 and other battery cells, improving the compatibility of each battery cell within the solar cell module.
[0042] In some embodiments, in the first direction D1, the width of the two battery cells including the first edge 11 and the second edge 12 is greater than or equal to 44.9 mm and less than or equal to 49.9 mm, and the width of the other solar cells 10 is greater than or equal to 46.75 mm and less than or equal to 51.75 mm. Taking a solar cell with a size of 182.2*183.73 mm as an example, the first direction D1 is a direction parallel to the 183.75 mm edge. The width of the first battery cell 161 is 44.9 mm ≤ W1 ≤ 49.9 mm, the width of the fourth battery cell 164 is 44.9 mm ≤ W4 ≤ 49.9 mm, the width of the second battery cell 162 is 46.75 mm ≤ W2 ≤ 51.75 mm, and the width of the third battery cell 163 is 46.75 mm ≤ W3 ≤ 51.75 mm.
[0043] In some embodiments, in the first direction D1, the width of the two battery cells including the first edge 11 and the second edge 12 is greater than or equal to 51.5 mm and less than or equal to 56.5 mm, and the width of the other solar cells 10 is greater than or equal to 53.5 mm and less than or equal to 58.5 mm. Taking a 182*210 mm or 210*210 mm battery cell as an example, the first direction D1 is the direction parallel to the 210 mm edge, the width of the first battery cell 161 is 51.5 mm ≤ W1 ≤ 56.5 mm, the width of the fourth battery cell 164 is 51.5 mm ≤ W4 ≤ 56.5 mm, the width of the second battery cell 162 is 53.5 mm ≤ W2 ≤ 58.5 mm, and the width of the third battery cell 163 is 53.5 mm ≤ W3 ≤ 58.5 mm.
[0044] In some examples, the width of the segmented region 15 is 0.8 mm to 1.2 mm. In the first direction D1, the minimum distance between the electrode patterns of adjacent cell units is the width of the segmented region 15 between those adjacent cell units. The solar cell 10 can be segmented by laser processing along the center line of the segmented region 15.
[0045] According to another aspect of this disclosure, a solar cell 10 module is provided, the solar cell 10 module comprising all cell cells obtained by slicing the solar cell 10 along a slab region 15.
[0046] Finally, it should be noted that the above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. A solar cell, said solar cell having a first edge and a second edge opposite each other in a first direction, and a third edge and a fourth edge opposite each other in a second direction, the first direction being perpendicular to the second direction, characterized in that, The solar cell has three segmented regions spaced apart along a first direction. Each segmented region extends from the third edge to the fourth edge of the solar cell along a second direction, with the center line of the three segmented regions serving as the boundary. The solar cell includes four cell units connected sequentially along the first direction. In the first direction, the width of the two cell units containing the first edge and the second edge is 1.5mm-5mm smaller than the width of the other cell units.
2. The solar cell according to claim 1, characterized in that, In the first direction, the widths of two battery cells including the first edge and the second edge are equal, and the widths of other battery cells are equal.
3. The solar cell according to claim 1, characterized in that, Each of the battery cells has an electrode pattern on both the front and back surfaces, or only on the back surface. The area between the electrode patterns of adjacent battery cells that does not have an electrode pattern is constructed as a segmented area. In the first direction, the width of the electrode pattern of two battery cells including the first edge and the second edge is smaller than the width of the electrode pattern of other battery cells.
4. The solar cell according to claim 1, characterized in that, In the first direction, the width of the two battery cells adjacent to the first edge and the second edge is 1.5mm-2mm smaller than the width of the other battery cells, or 2mm-2.5mm smaller, or 2.5mm-3mm smaller, or 3mm-3.5mm smaller, or 3.5mm-4mm smaller, or 4mm-4.5mm smaller, or 4.5mm-5mm smaller.
5. The solar cell according to claim 1, characterized in that, In the first direction, the width of the two battery cells including the first edge and the second edge is greater than or equal to 44.9 mm and less than or equal to 49.9 mm, and the width of the other solar cells is greater than or equal to 46.75 mm and less than or equal to 51.75 mm.
6. The solar cell according to claim 1, characterized in that, In the first direction, the width of the two battery cells including the first edge and the second edge is greater than or equal to 51.5 mm and less than or equal to 56.5 mm, and the width of the other solar cells is greater than or equal to 53.5 mm and less than or equal to 58.5 mm.
7. The solar cell according to claim 1, characterized in that, The width of the segmented area is 0.8mm-1.2mm.
8. A solar cell module, characterized in that, Includes all of the solar cells obtained by cutting the solar cell according to any one of claims 1-7 along the segmented region.