Photovoltaic solder strip, battery assembly and photovoltaic system
By setting rough sections and forming multiple protrusions on the body of the photovoltaic welding strip, the problem of poor welding between the photovoltaic welding strip and the busbar was solved, and the welding strength and product yield were improved.
Patent Information
- Application Number
- CN202422484270.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-14
- Publication Date
- 2025-12-02
- Estimated Expiration
- 2034-10-14
AI Technical Summary
When welding photovoltaic strips and busbars, the difference in melting temperature leads to low welding tensile strength and poor welding results.
The design of photovoltaic welding ribbons includes at least one section of the ribbon body that is roughened. The surface of the roughened section has multiple protrusions, which are formed by embossing or other methods to increase the contact area with the busbar and the welding strength.
It improved the structural strength of the welding position, increased the tensile strength after welding, and enhanced the product yield.
Smart Images
Figure CN223626242U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of solar energy technology, and in particular relates to a photovoltaic welding strip, a battery module and a photovoltaic system. Background Technology
[0002] Solar cells, also known as photovoltaic cells, are devices that directly convert light energy into direct current using the photovoltaic effect. The PN junction on the semiconductor in a solar cell can directly convert solar energy into electrical energy through the photovoltaic effect. The most common type is the crystalline silicon solar cell, which includes monocrystalline silicon solar cells and polycrystalline silicon solar cells.
[0003] During the production of solar cells, multiple cells are connected in series using photovoltaic ribbons, which are then welded to busbars. However, because the photovoltaic ribbons and busbars are made of different materials, their melting temperatures differ during welding, resulting in low welding tensile strength and poor weld quality. Utility Model Content
[0004] The photovoltaic ribbon, battery module, and photovoltaic system provided in this embodiment of the invention aim to solve the problem of poor welding between photovoltaic ribbon and busbar in the prior art.
[0005] In a first aspect, embodiments of this utility model provide a photovoltaic welding strip, comprising:
[0006] The welding strip body has at least one rough section, and the rough section is located at least at the end of the welding strip body in the length direction for welding with the busbar. The surface of the rough section is provided with a plurality of protrusions.
[0007] Furthermore, the rough section is an embossed section.
[0008] Furthermore, the height range of the protrusion is 1μm≤d≤25μm.
[0009] Furthermore, the height range of the protrusion is 1μm≤d<16μm.
[0010] Furthermore, the length L1 of the rough segment is greater than or equal to 2 / 3 of the width d of the busbar.
[0011] Furthermore, the entire body of the welding strip is configured as the rough section.
[0012] Furthermore, the welding strip body is sheet-shaped, and at least one surface of the roughened section is provided with the protrusion; or the welding strip body is column-shaped, and at least a portion of the circumferential surface of the roughened section is provided with the protrusion.
[0013] Furthermore, the protrusion is one or more of the following: arc-shaped protrusion, block-shaped protrusion, wavy protrusion, or irregular protrusion.
[0014] Secondly, embodiments of the present invention provide a battery assembly, comprising:
[0015] Busbar;
[0016] The photovoltaic welding strip described above is connected to the busbar.
[0017] Secondly, this utility model provides a photovoltaic system including the battery module described above.
[0018] The beneficial effects achieved by this utility model are as follows: by setting at least one section of the welding strip body as a rough section, and the rough section is located at least at the end of the welding strip body in the length direction, since the surface of the rough section has multiple protrusions, the contact area with the busbar is increased when welding with the busbar, the uneven contact between the unfused area or the structure of the fused alloy layer is reduced, the structural strength of the welding position is improved, and the tensile strength after welding is increased, thereby improving the product yield. Attached Figure Description
[0019] Figure 1 This is a schematic diagram of the structure of a photovoltaic welding strip provided in an embodiment of this utility model;
[0020] Figure 2 This is a schematic diagram of another photovoltaic welding strip provided in this embodiment of the present invention;
[0021] Figure 3 This is a schematic diagram of another photovoltaic welding strip provided in this embodiment of the utility model.
[0022] Explanation of key component symbols: 100-photovoltaic ribbon, 10-ribbon body, 11-rough section, 12-protrusion, 13-substrate, 14-tin alloy layer, 16-groove, 17-protrusion layer. Detailed Implementation
[0023] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.
[0024] Briefly describe the distinguishing features between this utility model and the prior art, which constitute the utility model points of this utility model.
[0025] Example 1
[0026] Solar cells, also known as photovoltaic cells, mainly consist of a substrate, cell arrays, and glass. A cell array comprises multiple sets of cells connected in parallel, and each cell array consists of multiple cells arranged side by side. The cells in a cell array are connected by multiple photovoltaic ribbons, and each series of cells is connected by a busbar to achieve centralized current output.
[0027] The solar cells can be made of semiconductor materials, such as P-type silicon wafers, which form a PN junction after phosphorus diffusion. When the semiconductor structure absorbs sunlight, it generates electron-hole pairs. These pairs are separated by the built-in electric field of the PN junction inside the semiconductor, with electrons flowing into the N-region and holes flowing into the P-region, thus forming a photogenerated electric field.
[0028] It should be noted that both the photovoltaic welding ribbon 100 and the busbar are made of metal. During welding, under heating and / or pressure, atomic bonding occurs between two metals of the same or different types, thereby achieving the welding effect.
[0029] In related technologies, the photovoltaic ribbon 100 and the busbar mainly consist of a substrate and a surface coating. The main function of the substrate is to conduct electricity. It is generally made of metals such as copper and aluminum, which have good conductivity, certain structural strength and corrosion resistance, can withstand high voltage and high current, and can operate under a wide range of temperature and humidity conditions. Therefore, it is the material used as the substrate. The main function of the surface coating is to make the photovoltaic ribbon 100 and the busbar weldable, enabling a stable weld to achieve the conductivity function. The surface coating generally uses a tin alloy, and the coating material can be uniformly covered on the surface of the substrate 13 using processes such as electroplating, vacuum deposition, spraying, and hot-dip coating.
[0030] The difference in the doped metals of the tin alloy layer on the surfaces of the photovoltaic solder ribbon 100 and the busbar leads to different melting temperatures during welding. When the difference in melting temperatures is greater than or equal to 30°C, and because the photovoltaic solder ribbon 100 is very small and has a small contact area with the busbar during welding, the welding pull is low, resulting in poor welding between the two.
[0031] To resolve the above technical issues, please refer to Figure 1 The photovoltaic welding ribbon 100 provided by this utility model includes a welding ribbon body 10. The structure of the welding ribbon body 10 is as follows: Figure 1 or Figure 2 As shown, it includes a substrate 13 and a tin alloy layer 14 disposed on the surface of the substrate 13.
[0032] Please refer to Figure 1At least one section of the welding strip body 10 is a rough section 11, and the rough section 11 is located at least at the end of the welding strip body 10 in the length direction for welding with the busbar. The surface of the rough section 11 is provided with a plurality of protrusions 12.
[0033] The aforementioned photovoltaic welding ribbon 100, by setting at least one section of the welding ribbon body 10 as a rough section 11, and the rough section 11 is located at least at the end of the welding ribbon body 10 in the length direction, since the surface of the rough section 11 has a plurality of protrusions 12, increases the contact area with the busbar when welding with the busbar, reduces the uneven contact between the unfused areas or the structure of the fused alloy layer, improves the structural strength of the welding position, and thus improves the tensile strength after welding and improves the product yield.
[0034] In this embodiment, the thickness of the substrate 13 can be set to 0.01mm-0.5mm. For example, it can be set to values such as 0.01mm, 0.05mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, and 0.5mm. This ensures that the thickness of the copper core is within a suitable range, avoiding the situation where the substrate 13 is too thin, resulting in poor strength and conductivity of the entire photovoltaic ribbon 100. It also avoids the waste of materials and increased costs caused by an excessively thick substrate 13.
[0035] The thickness of the tin alloy layer 14 is 3μm-25μm. For example, it can be set to values such as 3μm, 7μm, 9μm, 11μm, 13μm, 15μm, 20μm, or 25μm, and is not limited here. This ensures that the thickness of the tin alloy layer 14 is within a suitable range, avoiding poor soldering results due to an excessively thin tin alloy layer, and also avoiding material waste and increased costs due to an excessively thick tin alloy layer. The tin alloy layer 14 is a tin alloy, including but not limited to at least one of SnPb, SnBi, and SnAg layers, and is not specifically limited here.
[0036] Example 2
[0037] When forming the roughened section 11 on the solder strip body 10, the roughened section 11 can be set as an embossed section, that is, formed by an embossing process. Pressure is used to deform the surface of the solder strip body 10, thereby forming a raised pattern. Thus, pressure can be directly applied to the solder strip body 10 to deform it, quickly forming the protrusions 12. Specifically, when the surface of the solder strip body 10 is deformed, not only are multiple protrusions 12 formed, but grooves 16 are also present between the protrusions 12. Furthermore, when the roughened section 11 is formed by the embossing process, the pressure can deform the tin alloy layer 14, or it can simultaneously deform the substrate 13.
[0038] Or in other embodiments, such as Figure 2 As shown, the rough section 11 can be a frosted section, for example, by using sandblasting, electroplating, or electrophoresis to form a new raised layer 17 on the solder strip body 10. Understandably, the raised layer 17 is provided on the surface of the tin alloy layer 14. The rough section 11 can be formed by the setting of the raised layer 17. Understandably, since the raised layer 17 is a plurality of particles provided on the surface of the tin alloy layer 14, the particles are raised 12, and there are also grooves 16 between the particles.
[0039] Example 3
[0040] Furthermore, when forming the embossed section using an embossing process, since the thickness of the tin alloy layer 14 is 3μm-25μm, the height range of the protrusion 12 is set to 1μm≤d≤25μm. Since the groove 16 is formed simultaneously with the protrusion 12, the depth range of the groove 16 is 1μm≤d≤25μm. For example, the height of the protrusion 12 can be set to values such as 1μm, 5μm, 10μm, 15μm, 20μm, or 25μm, which are not limited here. In this way, the depth of the groove 16 is less than or equal to the thickness of the tin alloy layer 14, so as to avoid reducing the structural strength of the entire solder strip body 10 when the groove 16 is too deep, and to avoid not achieving a good fusion effect when welding with the busbar when the depth is too shallow.
[0041] Example 4
[0042] Furthermore, in this embodiment, the height range of the protrusion 12 is preferably 1μm≤d<16μm, that is, it is set to be less than the thickness of the tin alloy layer 14, so as to ensure the structural strength of the entire solder strip body 10, facilitate the formation of embossing, and reduce the opening cost.
[0043] Example 5
[0044] In one embodiment of this utility model, in order to ensure the welding effect of the rough section 11 and the busbar, the length L1 of the rough section 11 is greater than or equal to 2 / 3 of the width d of the busbar. This ensures that the rough section 11 has sufficient length to have sufficient contact area with the busbar, thereby ensuring the welding strength between the welding strip body 10 and the busbar and avoiding the connection strength between the rough section 11 and the busbar being affected due to insufficient length of the rough section 11.
[0045] For example, the length L1 of the roughened section 11 can be 2 / 3, 7 / 10, 4 / 5, or 9 / 10 of the width d of the busbar, or it can be set to the same width as the busbar. Alternatively, the length L1 of the roughened section 11 can be set to be greater than the width d of the busbar. All of these methods can ensure the welding strength of the busbar.
[0046] For example, when the width d of the busbar is set to 6 mm, and the length L1 of the rough section 11 is 2 / 3 of the width d of the busbar, then the length L1 of the rough section 11 is 4 mm; when the length L1 of the rough section 11 is 7 / 10 of the busbar, then the length L1 of the rough section 11 is 4.2 mm; when the length L1 of the rough section 11 is 4 / 5 of the busbar, then the length L1 of the rough section 11 is 4.8 mm; when the length L1 of the rough section 11 is the same as the length of the busbar, then the length L1 of the rough section 11 is 6 mm; furthermore, the length of the rough section 11 can be set to be greater than 6 mm.
[0047] Example 6
[0048] Further, please refer to Figure 3 Since the solder ribbon body 10 needs to be connected to the fine grid on the battery cell, in order to ensure the connection effect with the fine grid, the solder ribbon body 10 is set with rough sections 11. Thus, the entire surface of the solder ribbon body 10 is provided with protrusions 12, which can increase the contact area between the two when laminating with the fine grid, improve the connection stability, better collect current, and improve the current collection effect. At the same time, since the surface of the solder ribbon body 10 is provided with protrusions 12 along the entire length direction, it also has the effect of increasing the structural strength of the entire solder ribbon body 10.
[0049] When the entire solder strip body 10 is set as a rough section 11, the entire solder strip body 10 can be set as an embossed section, that is, a protrusion 12 is formed on the surface of the entire solder strip body 10 by an embossing process; or a sandblasting process, electroplating, or electrophoresis process can be used to form a protrusion 12 on the surface of the entire solder strip body 10, which is not limited here.
[0050] Example 7
[0051] In one embodiment of this utility model, the photovoltaic welding ribbon 100 can be configured as a sheet or as a column.
[0052] (1) When the ribbon body 10 is in sheet form, a protrusion 12 can be provided on at least one surface of the rough section 11. That is, a protrusion 12 can be provided on the surface of the ribbon body 10 where welding is required and the junction head is to be performed, or a protrusion 12 can be provided on both opposite surfaces of the ribbon body 10, thereby increasing the structural strength of the photovoltaic ribbon.
[0053] Furthermore, the entire welding strip body 10 can be a rough section 11, that is, protrusions 12 are provided on both opposite surfaces of the entire welding strip body 10.
[0054] (2) When the welding strip body 10 is set in a columnar shape, at least a portion of the circumferential surface of the rough section 11 is provided with protrusions 12. That is, the protrusions 12 can be provided on the circumferential surface of the part that needs to be contacted and welded with the busbar, or the protrusions 12 can be provided on the entire circumferential surface of the rough section 11, thereby increasing the structural strength of the photovoltaic welding strip.
[0055] Furthermore, the entire welding strip body 10 can be a rough section 11, that is, protrusions 12 are provided on the circumferential surface of the entire welding strip body 10. In this way, by setting protrusions 12 along the entire length direction, the structural strength of the entire photovoltaic welding strip 100 can be increased.
[0056] Example 8
[0057] When protrusions 12 are provided on the surface of the rough section 11, the shapes of the protrusions 12 can be the same or different. For example, they can be one or more of the following: arc-shaped protrusions, block-shaped protrusions, wavy protrusions, or irregular protrusions. That is, only one type of protrusion 12 can be provided on the surface of the rough section 11, or multiple types of protrusions 12 can be combined. In this way, by providing protrusions 12, the welding yield between the protrusions and the busbar can be improved.
[0058] Among them, the arc-shaped protrusion 12 can be a hemispherical protrusion, the block-shaped protrusion 12 can be square, rectangular, trapezoidal, or serrated protrusion 12, such as... Figures 1 to 3 As shown; or multiple wavy protrusions 12 arranged in parallel along the length of the solder strip body 10, or wavy protrusions 12 arranged in parallel along the width of the solder strip body 10.
[0059] In a preferred embodiment, in order to facilitate the setting of the rough section 11 and reduce the opening cost, when the protrusions 12 are set on the rough section 11, the protrusions 12 are all the same shape, thereby facilitating the forming of the protrusions 12.
[0060] The aforementioned photovoltaic solder ribbon 100, by setting the rough section 11 as an embossed section, allows for direct pressure application onto the solder ribbon body 10, quickly forming protrusions 12 on the solder ribbon body 10. This facilitates rapid forming of the solder ribbon body 10 and improves manufacturing efficiency. When setting the protrusions 12 by embossing, the height of the protrusions 12 is within the range of 1μm≤d≤25μm, i.e., the depth of the groove 16 is within the range of 1μm≤d≤25μm. The depth of the recess is less than or equal to the thickness of the tin alloy layer 14. This avoids pressing the solder ribbon body 10 too deeply, which would reduce the structural strength of the entire solder ribbon body 10, and avoids the recess being too shallow, which would result in poor fusion when welding with the busbar. Furthermore, different shapes of protrusions 12 can be combined when setting the protrusions 12. Alternatively, protrusions 12 of a single shape can be set, all of which can improve the welding yield between the solder strip body 10 and the busbar. At the same time, the length L1 of the rough section 11 is set to be greater than or equal to 2 / 3 of the width d of the busbar, so that the rough section 11 has sufficient length to have sufficient contact area with the busbar, thereby ensuring the welding strength between the solder strip body 10 and the busbar. Furthermore, the entire solder strip body 10 can be set as the rough section 11. In this case, the entire surface of the solder strip body 10 is provided with protrusions 12, which can increase the contact area between the two when laminating with the fine grid, improve the stability of the connection, and better collect current. At the same time, since the surface of the solder strip body 10 is provided with protrusions 12 along the entire length direction, it also has the effect of increasing the structural strength of the entire solder strip body 10.
[0061] Example 9
[0062] This utility model also provides a battery module, including a back sheet, photovoltaic glass, and multiple battery cells sandwiched between the back sheet and the photovoltaic glass, a busbar, and the aforementioned photovoltaic welding ribbon 100. The photovoltaic welding ribbon 100 is used to connect multiple battery cells in series to form a battery string. The photovoltaic welding ribbon 100 in the multiple battery strings is then welded through the busbar to achieve current collection and output through the busbar, thereby obtaining the battery module.
[0063] The aforementioned battery assembly, by setting at least one section of the solder strip body 10 as a rough section 11, and the rough section 11 being located at least at the end of the solder strip body 10 in the length direction, since the surface of the rough section 11 has a plurality of protrusions 12, increases the contact area with the busbar when welding with the busbar, reduces the uneven contact between the unfused areas or the structure of the fused alloy layer, improves the structural strength of the welding position, thereby increasing the tensile strength after welding, improving the product yield, and thus improving the overall product quality of the battery assembly.
[0064] Example 10
[0065] In Embodiment 10, this utility model also provides a photovoltaic system, including the aforementioned battery components. The photovoltaic system can be applied in photovoltaic power stations, such as ground-mounted power stations, rooftop power stations, and water-based power stations. It can also be applied to equipment or devices that utilize solar energy to generate electricity, such as user solar power supplies, solar streetlights, solar cars, and solar buildings.
[0066] The aforementioned photovoltaic system, by setting at least one section of the welding strip body 10 as a rough section 11, and the rough section 11 being located at least at the end of the welding strip body 10 in the length direction, since the surface of the rough section 11 has multiple protrusions 12, increases the contact area with the busbar when welding with it, reduces the uneven contact between the unfused areas or the structure of the fused alloy layer, improves the structural strength of the welding position, thereby increasing the tensile strength after welding, improving the product yield, and thus improving the overall product quality of the battery module, while also improving the stability of the entire photovoltaic system.
[0067] It is understood that those skilled in the art can combine various implementation methods in the above embodiments under the guidance of the above examples to obtain technical solutions with multiple implementation methods.
[0068] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements 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 photovoltaic welding strip, characterized in that, include: The solder strip body has at least one rough section located at least at the end of the length direction of the solder strip body for soldering with a busbar. The surface of the rough section is provided with a plurality of protrusions, and grooves are formed between the protrusions. The solder strip body includes a substrate and a tin alloy layer. The protrusions and the grooves are formed in the tin alloy layer, and the depth of the grooves is less than or equal to the thickness of the tin alloy layer.
2. The photovoltaic welding strip as described in claim 1, characterized in that, The rough section is the embossed section.
3. The photovoltaic welding strip as described in claim 2, characterized in that, The height range of the protrusion is 1μm≤d≤25μm.
4. The photovoltaic welding strip as described in claim 3, characterized in that, The height range of the protrusion is 1μm≤d<16μm.
5. The photovoltaic welding strip as described in any one of claims 1-3, characterized in that, The length L1 of the rough section is greater than or equal to 2 / 3 of the width d of the busbar.
6. The photovoltaic welding strip as described in any one of claims 1-3, characterized in that, The weld strip body is all configured as the rough section.
7. The photovoltaic welding strip as described in any one of claims 1-3, characterized in that, The welding strip body is sheet-shaped, and at least one surface of the roughened section is provided with the protrusion; or the welding strip body is column-shaped, and at least a portion of the circumferential surface of the roughened section is provided with the protrusion.
8. The photovoltaic welding strip as described in any one of claims 1-3, characterized in that, The protrusion is one or more of the following: arc-shaped protrusion, block-shaped protrusion, wavy protrusion, or irregular protrusion.
9. A battery assembly, characterized in that, include: Busbar; The photovoltaic ribbon as described in any one of claims 1-8, wherein the photovoltaic ribbon is connected to the busbar.
10. A photovoltaic system, characterized in that, Includes the battery assembly as described in claim 9.