Solar cell and photovoltaic module

Abstract

The utility model is applicable to the technical field of solar cells, and provides a solar cell and a photovoltaic assembly, the solar cell comprises a cell sheet, and main grids and fine grids arranged on the back surface of the cell sheet, the main grids and the fine grids are arranged in a crossed manner, the main grids are connected with the fine grids with the same polarity, the main grids are electrically isolated from the fine grids with different polarities, and the main grids are electrically isolated from the fine grids with different polarities. The back surface of the battery piece comprises an edge area and a middle area located in the middle of the edge area, and the electrical isolation distance between the main grid located in the edge area and the fine grids with different polarities is larger than the electrical isolation distance between the main grid located in the middle area and the fine grids with different polarities. By increasing the distance between the main grid in the marginal area and the fine grids with different polarities, the part, located in the marginal area, of the main grid does not make contact with the adjacent fine grids with different polarities under the condition that the part shifts under the action of external force, so that the short circuit phenomenon is avoided, and the safety of the solar cell is ensured.

Description

Technical Field

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

[0002] The surface of the solar cell is provided with metal grid lines, which include main grids and fine grids. The fine grids are used to collect currents of corresponding polarity, and the main grids are used to collect the currents collected by the fine grids, and then transmit the collected currents to the welding strip output through the main grids.

[0003] The busbars include positive and negative busbars, and similarly, the fine grids include positive and negative fine grids. The positive busbar is connected to the positive fine grid but not to the negative fine grid. Similarly, the negative busbar is connected to the negative fine grid but not to the positive fine grid. In other words, the positive busbar is electrically isolated from the negative fine grid, and the negative busbar is electrically isolated from the positive fine grid.

[0004] In traditional solutions, the electrical isolation distance between a busbar and thin grids of different polarities is the same. That is, the distance between the positive busbar and multiple negative thin grids is the same, and the distance between the negative busbar and multiple positive thin grids is the same. The portion of the busbar near the edge of the cell can shift slightly when subjected to external forces, causing the busbar to contact thin grids of different polarities and cause a short circuit. Utility Model Content

[0005] The present invention provides a solar cell, aiming to solve the problem that the main grid of the existing solar cell near the edge of the cell is easily deflected when subjected to external force and contacts fine grids of different polarities, causing a short circuit.

[0006] The embodiment of the present utility model is implemented as follows: a solar cell comprising:

[0007] Battery cells;

[0008] The main grid and fine grid are arranged on the back of the solar cell, and the main grid and fine grid are arranged crosswise;

[0009] The main grid is connected to the fine grid of the same polarity, and the main grid is electrically isolated from the fine grid of different polarities;

[0010] The back side of the cell includes an edge region and a middle region located in the middle of the edge region. The electrical isolation distance between the main grid in the edge region and the fine grids of different polarities is greater than the electrical isolation distance between the main grid in the middle region and the fine grids of different polarities.

[0011] Furthermore, the electrical isolation distance between the main grid in the edge region and the fine grids of different polarities is D1, 0 mm < D1 ≤ 10 mm, and the electrical isolation distance between the main grid in the middle region and the fine grids of different polarities is D2, 0 mm < D1 ≤ 5 mm.

[0012] Furthermore, an insulating adhesive layer is provided at the position of the fine grid.

[0013] Furthermore, the insulating adhesive layer includes at least one of a UV-curing insulating adhesive layer, an organic silicone layer, a thermally conductive insulating potting adhesive layer, and a silicone sealant layer.

[0014] Furthermore, the solar cell further includes a welding strip, a welding material is provided on the surface of the main grid, and the main grid is electrically connected to the welding strip through the welding material.

[0015] Furthermore, the solder is solder paste.

[0016] Furthermore, the melting points of the solder and the solder strip are both 100° to 130°.

[0017] In a second aspect, the present application further provides a photovoltaic assembly comprising the solar cell as described above.

[0018] Furthermore, the photovoltaic module includes a front cover plate, a front adhesive film, a battery array, a back adhesive film and a back cover plate stacked in sequence, and the battery array is the above-mentioned solar cell.

[0019] The beneficial effects of the present application are as follows: The solar cell provided by the present application includes a cell and a main grid and fine grids arranged on the back of the cell, the main grid and the fine grids being arranged crosswise with each other, the main grid being connected to the fine grids of the same polarity, and the main grid being electrically isolated from the fine grids of different polarities, the back of the cell including an edge region and an intermediate region located in the middle of the edge region, the distance of electrical isolation between the main grid located in the edge region and the fine grids of different polarities being greater than the distance of electrical isolation between the main grid located in the intermediate region and the fine grids of different polarities. By increasing the distance between the main grid in the edge region and the fine grids of different polarities, even if the portion of the main grid located in the edge region is offset by an external force, it will not contact the adjacent fine grids of different polarities, thus preventing a short circuit and ensuring the safety of the solar cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the grid line structure of an embodiment of a solar cell provided by the present application;

[0021] Figure 2 yes Figure 1 A magnified schematic diagram of part A1;

[0022] Figure 3 yes Figure 1 Enlarged schematic diagram of part B1.

[0023] Explanation of reference numerals: 100, main grid; 110, positive electrode main grid; 120, negative electrode main grid; 200, fine grid; 210, positive electrode fine grid; 220, negative electrode fine grid; 500, battery cell. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. Examples of embodiments are shown in the accompanying drawings, in which the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and are not to be construed as limiting the present invention. In addition, it should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0025] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "left", "right", "horizontal", "top", "bottom", etc., indicating the orientation or position relationship, are based on the orientation or position relationship 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 orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0026] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features being referred to. Thus, features defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this utility model, "plurality" means two or more, unless otherwise specifically defined.

[0027] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections, or mutual communication; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on specific circumstances.

[0028] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0029] The disclosure below provides many different embodiments or examples for realizing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. In addition, the present invention may repeat reference values ​​and / or reference letters in different examples. Such repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present invention provides examples of various specific processes and materials, but a person of ordinary skill in the art will recognize the application of other processes and / or the use of other materials.

[0030] The solar cell provided by the present application includes a cell and a main grid and fine grids arranged on the back of the cell. The main grid and fine grids are arranged crosswise with each other. The main grid is connected to the fine grids of the same polarity, and the main grid is electrically isolated from the fine grids of different polarities. The back of the cell includes an edge region and an intermediate region located in the middle of the edge region. The distance of electrical isolation between the main grid located in the edge region and the fine grids of different polarities is greater than the distance of electrical isolation between the main grid located in the intermediate region and the fine grids of different polarities. By increasing the distance between the main grid in the edge region and the fine grids of different polarities, even if the portion of the main grid located in the edge region is offset by external force, it will not contact the adjacent fine grids of different polarities, thus preventing a short circuit and ensuring the safety of the solar cell.

[0031] Example 1

[0032] like Figures 1 to 3 As shown, one embodiment of the present application provides a solar cell, comprising:

[0033] Battery cell 500;

[0034] The main grid 100 and the fine grid 200 are arranged on the back side of the solar cell 500, and the main grid 100 and the fine grid 200 are arranged to cross each other;

[0035] The main gate 100 is connected to the fine gate 200 of the same polarity, and the main gate 100 is electrically isolated from the fine gate 200 of different polarity;

[0036] The back side of the cell 500 includes an edge region and a middle region. The electrical isolation distance between the main grid 100 in the edge region and the fine grids 200 of different polarities is greater than the electrical isolation distance between the main grid 100 in the middle region and the fine grids 200 of different polarities.

[0037] In practice, solar cells are also known as solar photovoltaics (abbreviated as PV). They are photoelectric semiconductor wafers that use sunlight to generate electricity directly. They are also called "solar chips" or "photocells". As long as the solar cell is illuminated by light that meets certain illumination conditions, it can instantly output voltage and generate current in the presence of a circuit.

[0038] In some possible embodiments, the battery cell includes a substrate (not shown in the figure), a p-region (not shown in the figure), an n-region (not shown in the figure), and a passivation layer (not shown in the figure), etc., which are not limited.

[0039] During implementation, the substrate can be an N-type silicon wafer or a P-type silicon wafer, wherein the N-type silicon wafer is obtained by adding pentavalent elements (such as phosphorus or arsenic) to the silicon raw material. These pentavalent elements provide additional free electrons; the P-type silicon wafer is obtained by adding trivalent elements (such as boron or gallium) to the silicon raw material. These trivalent elements control the diffusion of electron holes and will not be elaborated on.

[0040] The substrate has a front side and a back side, wherein the front side of the substrate corresponds to the front side of the cell, and the front side of the cell can be regarded as the light-receiving side of the solar cell. Similarly, the back side of the substrate corresponds to the back side of the cell, and the back side of the cell can be regarded as the backlight side of the solar cell.

[0041] Optionally, the substrate can be a single crystal silicon wafer, which is a single crystal formed by melting silicon raw material and then slowly cooling it. The crystal structure is compact and orderly, and it has high conversion efficiency, stability and lifespan.

[0042] Alternatively, the substrate may be a polycrystalline silicon wafer, which is a form of elemental silicon. When molten elemental silicon solidifies under supercooling conditions, silicon atoms are arranged in a diamond lattice to form numerous crystal nuclei. When these nuclei grow into grains with different crystal plane orientations, these grains combine to form polycrystalline silicon.

[0043] Optionally, the surface of the substrate can be a polished surface or a textured surface, without limitation. The textured surface is produced by performing a texture process on the surface of the substrate to create an uneven pyramidal structure. The uneven textured surface utilizes the light trapping effect to increase sunlight absorption, reduce reflectivity, increase short-circuit current, and improve the photoelectric conversion efficiency of the solar cell.

[0044] Optionally, the texturing process includes but is not limited to acid texturing, alkali texturing, mechanical texturing, electrochemical texturing, reactive ion etching texturing, laser texturing and mask texturing, etc., which will not be described in detail.

[0045] The p-region is the positive electrode region of the solar cell, and the n-region is the negative electrode region of the solar cell. For example, taking an n-type silicon wafer as an example, the p-region can be formed by doping trivalent elements such as boron on the n-type silicon wafer, and the n-region can be formed by doping pentavalent elements such as phosphorus on the n-type silicon wafer. I will not go into details here.

[0046] The passivation layer is used to improve the photovoltaic conversion efficiency and stability of solar cells, reduce surface damage and oxidation reactions, and extend the service life of solar cells. In some possible embodiments, the passivation layer includes silicon nitride, silicon oxynitride, titanium dioxide, aluminum oxide, and ferric oxide, etc., without limitation.

[0047] It should be noted that the above-mentioned battery cell including the substrate, p-region, n-region and passivation layer is an example of the embodiment of the present application, and is not a specific limitation of the present application. In some other embodiments, the battery cell may also include other structures, such as an anti-reflection layer, etc., which are not limited.

[0048] The cell is provided with metal electrodes, which include a main grid 100 and fine grids 200. The fine grids 200 are used to collect current of corresponding polarity. For example, the fine grids 200 include a positive fine grid 210 and a negative fine grid 220. Multiple positive fine grids 210 and multiple negative fine grids 220 are alternately distributed, i.e., there is a negative fine grid 220 between two positive fine grids 210, and there is a positive fine grid 210 between two negative fine grids 220. The positive fine grid 210 is located in the p-region to collect current in the p-region, while the negative fine grid 220 is located in the n-region to collect current in the n-region.

[0049] The main grid 100 is used to collect the current collected by the fine grid 200. The main grid 100 includes a positive main grid 110 and a negative main grid 120. The positive main grid 110 is connected to the positive fine grid 210 and is electrically isolated from the negative fine grid 220. It is used to collect the current collected by multiple positive fine grids 210. The negative main grid 120 is connected to the negative fine grid 220 and is electrically isolated from the positive fine grid 210. It is used to collect the current collected by multiple negative fine grids 220. No further details will be given.

[0050] During implementation, electrical isolation means that the two are not in direct contact. For example, electrical isolation between the positive electrode main grid 110 and the negative electrode fine grid 220 means that the positive electrode main grid 110 and the negative electrode fine grid 220 are separated and not in contact, and electrical isolation between the negative electrode main grid 120 and the positive electrode fine grid 210 means that the negative electrode main grid 120 and the positive electrode fine grid 210 are separated and not in contact, so as to avoid short circuit.

[0051] Optionally, the main gate 100 and the fine gate 200 are arranged crosswise. Usually, the main gate 100 and the fine gate 200 are perpendicular or substantially perpendicular. For example, when the fine gate 200 is parallel to the horizontal plane, the main gate 100 is perpendicular or substantially perpendicular to the horizontal plane. No further details are given.

[0052] Since the main grid 100 is electrically isolated from multiple fine grids 200 of different polarities, there is a certain distance between the main grid 100 and the fine grids 200 of different polarities, that is, there is an electrically isolated distance between the positive main grid 110 and the negative fine grid 220, and there is an electrically isolated distance between the negative main grid 120 and the positive fine grid 210.

[0053] Exemplarily, the main grid 100 is in the shape of a long strip, and the ends of the main grid 100 are located in the edge area. That is, the battery cell 500 has two edge areas. For example, when the main grid 100 is set vertically, the upper and lower ends of the battery cell 500 are the edge areas.

[0054] Compared with the edge area and the middle area, the electrical isolation distance between the main grid 100 and the fine grids 200 of different polarities is larger, that is, the electrical isolation distance between the positive main grid 110 and the negative fine grid 220 located in the edge area is greater than the electrical isolation distance between the positive main grid 110 and the negative fine grid 220 located in the middle area. Similarly, the electrical isolation distance between the negative main grid 120 and the positive fine grid 210 located in the edge area is greater than the electrical isolation distance between the negative main grid 120 and the positive fine grid 210 located in the middle area.

[0055] Exemplarily, the electrical isolation distance between the positive main grid 110 and the negative fine grid 220 in the edge region is recorded as D1, and the electrical isolation distance between the positive main grid 110 and the negative fine grid 220 in the middle region is recorded as D2, and D1 is greater than D2.

[0056] Optionally, D1 is less than 10 mm, for example, D1 may be 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, or 9 mm, etc. D2 is less than 5 mm, for example, D2 may be 1 mm, 2 mm, 3 mm, or 4 mm, etc., as long as D1 is greater than D2, there is no limitation.

[0057] It can be understood that the electrical isolation distance between the negative main grid 120 and the positive fine grid 210 located in the edge area can also be recorded as D1, and the electrical isolation distance between the negative main grid 120 and the positive fine grid 210 located in the middle area can also be recorded as D2, which will not be repeated.

[0058] The present application increases the distance between the main grid 100 in the edge area and the fine grids 200 of different polarities. When the portion of the main grid 100 located in the edge area is offset by external force, it will not contact the adjacent fine grids 200 of different polarities, thereby preventing a short circuit and ensuring the safety of the solar cell.

[0059] In some optional embodiments, an insulating adhesive layer (not shown) is provided at the position of the fine gate 200. The insulating adhesive layer can play a role in regional insulation, thereby effectively preventing short circuits caused by contact between gate lines of different polarities.

[0060] Optionally, the insulating adhesive layer includes at least one of a UV-curing insulating adhesive layer, an organic silicone layer, a thermally conductive insulating potting adhesive layer, and a silicone sealant layer, without limitation.

[0061] In some optional embodiments, the solar cell provided in the present application further includes a soldering ribbon (not shown in the figure), and a soldering material (not shown in the figure) is provided on the surface of the main grid 100. The main grid 100 is electrically connected to the soldering ribbon through the soldering material. During implementation, the soldering material includes at least one of tin, lead, and bismuth. For example, the soldering material can be tin paste, without limitation. Optionally, the melting points of the soldering material and the soldering ribbon are both 100° to 130°. For example, the melting points of the soldering material and the soldering ribbon are both 110°, 115°, 120°, 125°, or any value between 100° and 130°, without limitation.

[0062] During the welding process, the solder is screen-printed onto the main grid 100. After the solder strip is placed on the solder, it is pre-cured. Pre-curing ensures that the solder paste has not completely solidified (there is still flux residue) during the solder strip welding process, so as to ensure that the solder strip is initially bonded to the main grid 100. Then the subsequent lamination process is carried out. The combination of the solder strip and the main grid 100 is completed by relying on the temperature of the laminator. The melting point of the solder strip can be 100℃~130℃, which is lower than the lamination temperature of 150℃. It can effectively ensure the effective combination of the solder strip and the main grid 100, and thus ensure the current collection reliability of the solder strip.

[0063] Example 2

[0064] In some optional embodiments, the present application provides a photovoltaic assembly comprising the solar cell as described above.

[0065] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the structure and implementation principle of the photovoltaic assembly described above can refer to the corresponding structure and implementation principle in the aforementioned embodiment 1, and will not be repeated here.

[0066] In some embodiments, the photovoltaic module provided in the present application includes a laminate, which includes a front cover, a front film, a battery array, a back film and a back cover stacked in sequence. The battery array is the above-mentioned solar cell and will not be described in detail.

[0067] The solar cell provided in this application includes a cell 500 and a main grid 100 and fine grids 200 disposed on the back of the cell 500. The main grid 100 and fine grids 200 are arranged crosswise with each other. The main grid 100 is connected to the fine grids 200 of the same polarity, and the main grid 100 is electrically isolated from the fine grids 200 of different polarities. The back of the cell 500 includes an edge region and a middle region located between the edge region. The distance of electrical isolation between the main grid 100 in the edge region and the fine grids 200 of different polarities is greater than the distance of electrical isolation between the main grid 100 in the middle region and the fine grids 200 of different polarities. By increasing the distance between the main grid 100 in the edge region and the fine grids 200 of different polarities, even if the portion of the main grid 100 in the edge region is deflected by external force, it will not contact the adjacent fine grids 200 of different polarities, thus preventing a short circuit and ensuring the safety of the solar cell.

[0068] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A solar cell, characterized in that: include: Battery cells; A main grid and a fine grid are arranged on the back side of the solar cell, wherein the main grid and the fine grid are arranged to cross each other; The main grid is connected to the fine grid of the same polarity, and the main grid is electrically isolated from the fine grids of different polarities; The back side of the cell includes an edge region and a middle region located in the middle of the edge region. The electrical isolation distance between the main grid and the fine grids of different polarities located in the edge region is greater than the electrical isolation distance between the main grid and the fine grids of different polarities located in the middle region.

2. The solar cell according to claim 1, wherein The electrical isolation distance between the main grid in the edge region and the fine grids of different polarities is D1, 0 mm < D1 ≤ 10 mm, and the electrical isolation distance between the main grid in the middle region and the fine grids of different polarities is D2, 0 mm < D1 ≤ 5 mm.

3. The solar cell according to claim 1, wherein An insulating adhesive layer is provided at the position of the fine grid.

4. The solar cell according to claim 1, wherein The solar cell further includes a welding strip, a surface of the main grid is provided with welding material, and the main grid is electrically connected to the welding strip through the welding material.

5. The solar cell according to claim 4, wherein The solder is solder paste.

6. The solar cell according to claim 4, wherein The melting points of the solder and the solder strip are both 100° to 130°.

7. A photovoltaic module, characterized in that: The solar cell according to any one of claims 1 to 6 is included.

8. The photovoltaic module according to claim 7, wherein: The photovoltaic module comprises a front cover plate, a front adhesive film, a battery array, a back adhesive film and a back cover plate stacked in sequence, and the battery array is the solar cell.

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