Segmented photovoltaic solder ribbon

Abstract

The application discloses a segmented photovoltaic welding strip and relates to the technical field of photovoltaics. The welding strip comprises a first base material and a first coating layer covering the surface of the first base material; the first base material comprises a first strip body and a second strip body; the first strip body has a first surface and a second surface arranged oppositely, and the first surface is connected with the front surface of a first cell piece; the second strip body is connected with the back surface of a second cell piece; at least two protruding structures are arranged on the second surface along the length direction of the first strip body and extend to the outside of the first strip body, and a first groove structure is arranged between two adjacent protruding structures; the vertical distance between the top of the protruding structure and the bottom of the first groove structure is 25-90 microns; the cross section of the first groove structure along the thickness direction of the first strip body has a first inclined edge and a second inclined edge oppositely, and the included angle between the two is 70-160 degrees. The application can guarantee the light reflection effect, improve the power of the photovoltaic module, and reduce the cost of the photovoltaic module.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic technology, and in particular to a segmented photovoltaic welding strip. Background Technology

[0002] Solder ribbon is a crucial component of photovoltaic (PV) modules, primarily serving to connect solar cells to each other and to junction boxes. Existing solder ribbons come in various shapes, ranging from regular to irregular. Irregularly shaped solder ribbons have seen wider development and application due to their unique advantages not found in conventional soldering. Currently, existing irregularly shaped solder ribbons are typically triangular or circular structures with a base. This structure offers good light reflection; however, the overall thickness of the reflective section is relatively large, requiring a thicker encapsulating film during module encapsulation, thus increasing the cost of PV modules. Summary of the Invention

[0003] This invention provides a segmented photovoltaic ribbon that can ensure light reflection, improve the power of photovoltaic modules, and reduce the cost of photovoltaic modules.

[0004] This invention provides the following solution:

[0005] In a first aspect, a segmented photovoltaic ribbon is provided, comprising: a first substrate and a first coating covering the surface of the first substrate;

[0006] The first substrate includes a first strip and a second strip connected together;

[0007] The first strip has a first surface and a second surface disposed opposite to each other, and the first surface is connected to the front side of the first battery cell;

[0008] The second belt is connected to the back of the second battery cell;

[0009] The first and second battery cells are arranged longitudinally and adjacent to each other.

[0010] The second surface is provided with at least two protrusions arranged along the length direction of the first belt and extending outward from the first belt, and a first groove structure is provided between two adjacent protrusions.

[0011] The vertical distance between the top of the protruding structure and the bottom of the first groove structure is any value between 25 and 90 μm.

[0012] The first groove structure has a cross section along the thickness direction of the first strip with a first inclined side and a second inclined side, and the included angle between the first inclined side and the second inclined side is any value between 70° and 160°.

[0013] Optionally, the thickness of the first coating in the first groove structure is less than or equal to 10 μm.

[0014] Optionally, the vertical distance between the top of the protrusion structure and the bottom of the first groove structure is any value between 40 and 60 μm.

[0015] Optionally, the angle between the first hypotenuse and the second hypotenuse is any value between 120° and 130°.

[0016] Optionally, the first belt body further has a third surface and a fourth surface disposed opposite to each other, and the third surface and the fourth surface are both located between the first surface and the second surface;

[0017] Both the third surface and the fourth surface are provided with at least one second groove structure that is recessed into the interior of the first strip, and the depth of the second groove structure is any value between 3 and 30 μm.

[0018] Optionally, the depth of the second groove structure can be any value between 10 and 20 μm.

[0019] Optionally, the number of the protrusions is two, and the two protrusions are symmetrically arranged along the central axis of the first belt.

[0020] Optionally, the cross-section of the protrusion structure along the thickness direction of the first strip is one of the following: triangular, trapezoidal, semi-circular, semi-elliptical, trapezoidal with arcs on both sides, and triangular with arcs on both sides.

[0021] Optionally, the second strip has a fifth surface and a sixth surface disposed opposite to each other, the fifth surface being connected to the back side of the second battery cell, and the thickness of the first coating covering the sixth surface being any value between 2 and 20 μm.

[0022] Optionally, the thickness of the first coating covering the sixth surface is any value between 8 and 18 μm.

[0023] Optionally, the first substrate is made of copper, aluminum, gold or silver, and the first coating is a tin-lead alloy first coating.

[0024] In a second aspect, a segmented photovoltaic ribbon is also provided, comprising: a second substrate and a second coating covering the surface of the second substrate;

[0025] The second substrate includes a third strip and a fourth strip connected together;

[0026] The third belt is connected to the front side of the third battery cell;

[0027] The fourth strip has a seventh surface and an eighth surface arranged opposite to each other. The seventh surface is connected to the back of the fourth battery cell. The thickness of the second coating covering the eighth surface is any value between 2 and 20 μm.

[0028] The third and fourth battery cells are arranged longitudinally and adjacent to each other.

[0029] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0030] The segmented photovoltaic ribbon provided by this invention is disposed between the first and second solar cells, connecting them. The first ribbon is disposed on the front side of the first solar cell, reflecting sunlight onto an external object, which then reflects the sunlight again onto the first or second solar cell. By setting the protruding structure and the first groove structure, the area of ​​the first surface is increased, allowing more sunlight to be reflected, ensuring good light reflection. The cross-sectional area of ​​the first ribbon is also increased, resulting in lower resistance and thus improving the power of the photovoltaic module. By setting the vertical distance between the top of the protruding structure and the bottom of the first groove structure to be between 25 and 80 μm, and the angle between the first and second inclined sides to be between 80 and 150°, the excessive thickness of the first coating due to an excessively high vertical distance or a small angle is avoided, as is poor reflectivity due to an excessively small vertical distance or a large angle. This achieves both good reflectivity and reduced cost of the photovoltaic module.

[0031] Furthermore, by setting the second groove structure, not only can the width of the segmented photovoltaic ribbon be reduced, but the first coating at the corresponding position can also be hidden.

[0032] Furthermore, by setting the depth of the second groove structure to between 3 and 30 μm, a reasonable depth is obtained. This avoids the situation where the depth is too shallow and fails to reduce the width of the segmented photovoltaic strip, while also avoiding the situation where the depth is too deep and excessively reduces the cross-sectional area of ​​the segmented photovoltaic strip, leading to an increase in resistance.

[0033] Of course, the embodiments of the present invention do not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a partial structural cross-sectional view of a segmented photovoltaic ribbon provided in one embodiment of the present invention;

[0036] Figure 2 This is a schematic diagram of the structure of the first substrate of the segmented photovoltaic ribbon provided in one embodiment of the present invention;

[0037] Figure 3 This is a front view of the segmented photovoltaic ribbon and the solar cell assembly provided in one embodiment of the present invention;

[0038] Figure 4 This is a top view of the segmented photovoltaic ribbon and the solar cell assembly provided in one embodiment of the present invention;

[0039] Figure 5 This is a partial structural cross-sectional view of a segmented photovoltaic ribbon provided in another embodiment of the present invention. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.

[0041] It should be noted that the descriptions of "left," "right," "left side," "right side," "upper part," "lower part," "top," and "bottom" in this invention are defined based on the orientation or positional relationships shown in the accompanying drawings. They are merely for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the described structure must be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0042] In the description of this invention, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0043] Example 1

[0044] In view of the problems mentioned in the background art above, the present invention provides a segmented photovoltaic welding strip. Figure 1 This is a partial structural cross-sectional view of a segmented photovoltaic ribbon provided in one embodiment of the present invention. Figure 2 This is a schematic diagram of the structure of the first substrate of the segmented photovoltaic ribbon provided in one embodiment of the present invention. Figure 3 This is a front view of the segmented photovoltaic ribbon and the solar cell assembly provided in one embodiment of the present invention. Figure 4 This is a top view of the segmented photovoltaic ribbon and solar cell assembly provided in one embodiment of the present invention. Figure 1 As shown, see also Figures 2-4The segmented photovoltaic ribbon generally includes: a first substrate 100 and a first coating 200 covering the surface of the first substrate 100. The first substrate 100 includes, but is not limited to, a substrate made of metallic copper, aluminum, gold, or silver. The first coating 200 may include a coating formed of a metallic material such as a tin-lead alloy, and may also include a reflective film or reflective coating. The first substrate 100 includes a first strip 110 and a second strip 120 connected together. The first strip 110 has a first surface 112 and a second surface 111 disposed opposite to each other. The first surface 112 is connected to the front side of the first solar cell 300. The first strip 110 may also be referred to as a reflective segment. The second strip 120 is connected to the back side of the second solar cell 400. The second strip 120 may be configured to be flat, therefore the second strip 120 may also be referred to as a flat segment. The first solar cell 300 and the second solar cell 400 can have identical shapes and structures, arranged longitudinally and adjacent to each other. The segmented photovoltaic ribbon acts as an interconnecting strip, connecting several longitudinally arranged solar cells to form a battery string. Multiple battery strings are arranged laterally and connected by busbars. The front side refers to the side of the solar cell facing the sun, and the back side refers to the side facing away from the sun. At least two protrusions 113 are provided on the second surface 111, arranged along the length of the first strip 110 and extending outward from the first strip 110, and a first groove structure 114 is provided between two adjacent protrusions 113. That is, a protrusion 113 extending outward from its body is provided on the first strip 110. The vertical distance between the top of the protrusion 113 and the bottom of the first groove structure 114 is any value between 25 and 90 μm. The first groove structure 114 has a cross-section along the thickness direction of the first belt 110 with opposing first and second inclined sides, and the included angle between the first and second inclined sides is any value between 70° and 160°. The protrusion structure 113 can be regular or irregular in shape. Preferably, the cross-section of the protrusion structure 113 along the thickness direction of the first belt 110 is one of the following: triangular, trapezoidal, semi-circular, semi-elliptical, trapezoidal with arc-shaped sides, or triangular with arc-shaped sides.

[0045] The aforementioned segmented photovoltaic ribbon is disposed between the first solar cell 300 and the second solar cell 400, connecting the first solar cell 300 and the second solar cell 400. The first ribbon 110 is disposed on the front surface of the first solar cell 300, reflecting sunlight onto an external object, and then the sunlight is reflected again by the external object onto the first solar cell 300. By setting the protruding structure 113 and the first groove structure 114, the area of ​​the first surface 112 is increased, allowing more sunlight to be reflected and ensuring the light reflection effect. Simultaneously, the cross-sectional area of ​​the first ribbon 110 is increased, resulting in lower resistance and thus improving the power of the photovoltaic module. By setting the vertical distance between the top of the protruding structure 113 and the bottom of the first groove structure 114 to be between 25 and 90 μm, and setting the angle between the first inclined side and the second inclined side to be between 70 and 160°, it is possible to avoid the first coating 200 being too thick due to an excessively high vertical distance or an excessively small angle, and to avoid the reflective effect being poor due to an excessively small vertical distance or an excessively large angle. This achieves the goal of reducing the cost of photovoltaic modules while ensuring the reflective effect.

[0046] In a preferred embodiment, the thickness of the first coating in the first groove structure is less than or equal to 10 μm, thereby reducing the thickness of the corresponding first coating on the second surface 111, reducing the amount of encapsulant film required for photovoltaic modules, and reducing the cost of photovoltaic modules.

[0047] Preferably, the first surface 112 is connected to the main grid line on the front side of the first battery cell 300.

[0048] Preferably, the vertical distance between the top of the protrusion structure 113 and the bottom of the first groove structure 114 is any value between 40 and 60 μm, such as 40 μm, 50 μm or 60 μm. Due to space limitations, these will not be listed here.

[0049] Preferably, the included angle between the first hypotenuse and the second hypotenuse is any value between 120° and 130°, such as 120°, 125° or 130°. Due to space limitations, these will not be listed here.

[0050] Figure 5 This is a partial structural cross-sectional view of a segmented photovoltaic ribbon provided in another embodiment of the present invention. For example... Figure 5As shown, specifically, as an example of this application, the first strip 110 further has a third surface 115 and a fourth surface 116 disposed opposite to each other, and both the third surface 115 and the fourth surface 116 are located between the first surface 112 and the second surface 111, so that the cross-section of the first strip 110 is generally square. To reduce the width of the segmented photovoltaic ribbon and thus reduce its shading of the solar cells, this application provides at least one second groove structure 117 recessed into the interior of the first strip 110 on both the third surface 115 and the fourth surface 116. The depth of the second groove structure 117 is any value between 3 and 30 μm. The number of second groove structures 117 can be multiple, and they can be arranged in an orderly manner on the third surface 115 or the fourth surface 116, or they can be arranged randomly on the third surface 115 or the fourth surface 116. When fabricating the first coating 200 on the surface of the segmented photovoltaic ribbon, due to process limitations, the third surface 115 and the fourth surface 116 are also coated with the first coating 200. However, neither the third surface 115 nor the fourth surface 116 is connected to the solar cell, so the first coating 200 on them is ineffective. Therefore, it is desirable for the first coating 200 on the third surface 115 and the fourth surface 116 to be as thin as possible. By setting the second groove structure 117, not only can the width of the segmented photovoltaic ribbon be reduced, but the first coating 200 at the corresponding position can also be hidden. The depth of the second groove structure 117 is between 3 and 30 μm, which is a reasonable depth. This avoids the situation where the depth is too shallow and fails to reduce the width of the segmented photovoltaic ribbon, and also avoids the situation where the depth is too deep and excessively reduces the cross-sectional area of ​​the segmented photovoltaic ribbon, leading to an increase in resistance.

[0051] Preferably, the depth of the second groove structure 117 is any value between 10 and 20 μm, such as 10 μm, 15 μm or 20 μm. Due to space limitations, these will not be listed here.

[0052] Specifically, in one example of this application, the number of the protrusions 113 is two, and the two protrusions 113 are symmetrically arranged along the central axis of the first belt 110.

[0053] Preferably, as an example of this application, the cross-section of the protrusion structure 113 along the thickness direction of the first strip 110 is triangular, and all surfaces of the protrusion structure 113 can reflect light.

[0054] Preferably, as an example of this application, the second strip 120 has a fifth surface and a sixth surface disposed opposite to each other. The fifth surface is connected to the back surface of the second battery cell 400, and the thickness of the first coating 200 covering the sixth surface is any value between 2 and 20 μm. Optionally, the thickness of the first coating covering the sixth surface is controlled by applying a gas with a first preset pressure to the sixth surface during the preparation of the first coating 200. The first preset pressure is any value between 0.03 and 0.06 MPa.

[0055] It should be noted that the side of the first strip 110 and the second strip 120 that connects to the solar cell is the welding surface, and the side opposite to the welding surface is the non-welding surface. The first surface 112 and the fifth surface are welding surfaces, and the rest are non-welding surfaces. Using existing processes, both the welding and non-welding surfaces of the segmented photovoltaic ribbon are covered with a coating. The sixth surface is a non-welding surface and is not connected to the solar cell. The thickness of the first coating 200 on the existing non-welding surface is the same as that on the welding surface. This not only increases the cost of the ribbon but also makes the total thickness of the flat segment thicker, which is not conducive to reducing the thickness of the adhesive film, reducing microcracks in the solar cell, and further thinning the solar cell. Therefore, in this application, the thickness of the first coating 200 on the sixth surface is reduced by adding high-pressure blowing during the preparation of the first coating 200, so that the thickness of the first coating 200 on the sixth surface is less than that on the fifth surface. Of course, in order to avoid affecting the stability of the thickness of the first coating 200 and the yield of the segmented photovoltaic ribbon, the preset pressure should not be too high, and it is required to keep the thickness of the first coating 200 covering the sixth surface between 2 and 20 μm.

[0056] More preferably, the thickness of the first coating 200 covering the sixth surface is any value between 8 and 18 μm.

[0057] Example 2

[0058] This application also provides another segmented photovoltaic ribbon, which generally includes a second substrate and a second coating covering the surface of the second substrate. The second substrate includes a third and a fourth ribbon connected together. The third ribbon is connected to the front side of a third solar cell. The fourth ribbon has a seventh and an eighth surface disposed opposite to each other. The seventh surface is connected to the back side of the fourth solar cell. The thickness of the second coating covering the eighth surface is any value between 2 and 20 μm. The third and fourth solar cells are arranged longitudinally and adjacent to each other. Optionally, the thickness of the second coating covering the eighth surface is controlled by applying a gas with a second preset pressure to the eighth surface during the preparation of the second coating. Optionally, the second preset pressure is any value between 0.03 and 0.06 MPa. The second substrate includes, but is not limited to, a substrate made of metallic copper, aluminum, gold, or silver. The second coating may include a coating formed of a metallic material such as a tin-lead alloy, and may also include a reflective film or reflective coating.

[0059] The third strip can also be called the reflective section, and the fourth strip can be flat, therefore it can also be called the flat section. The third and fourth solar cells can have identical shapes and structures, arranged longitudinally and adjacent to each other. The segmented photovoltaic ribbons act as interconnecting strips, connecting several longitudinally arranged solar cells to form a battery string. Multiple battery strings are arranged laterally and connected by busbars. The front side refers to the side of the solar cell facing the sun, and the back side refers to the side facing away from the sun.

[0060] It should be noted that the side of the third and fourth strips that connects to the solar cell is the welding surface, and the side opposite to the welding surface is the non-welding surface. Using existing processes, both the welding and non-welding surfaces of the segmented photovoltaic ribbon are covered with a coating. The eighth surface is a non-welding surface and is not connected to the solar cell. The existing coating thickness on the non-welding surface is the same as that on the welding surface, which not only increases the cost of the ribbon but also makes the total thickness of the flat segment thicker, which is detrimental to reducing the thickness of the adhesive film, reducing microcracks in the solar cell, and further thinning the solar cell. Therefore, in this application, high-pressure blowing is added during the preparation of the second coating to reduce the thickness of the second coating on the eighth surface, making the thickness of the second coating on the eighth surface less than that on the seventh surface. Of course, to avoid affecting the stability of the second coating thickness and the yield of the segmented photovoltaic ribbon, the second preset pressure should not be too high, requiring it to maintain the thickness of the second coating covering the eighth surface between 2 and 20 μm.

[0061] The technical solution provided by this invention has been described in detail above. Specific examples have been used to illustrate the structure and implementation of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A segmented photovoltaic welding strip, characterized in that, include: A first substrate and a first coating covering the surface of the first substrate; The first substrate includes a first strip and a second strip connected together; The first strip has a first surface and a second surface disposed opposite to each other, and the first surface is connected to the front side of the first battery cell; The second belt is connected to the back of the second battery cell; The first and second battery cells are arranged longitudinally and adjacent to each other. The second surface is provided with at least two protrusions arranged along the length direction of the first belt and extending outward from the first belt, and a first groove structure is provided between two adjacent protrusions. The vertical distance between the top of the protruding structure and the bottom of the first groove structure is any value between 25 and 90 μm. The first groove structure has a cross section along the thickness direction of the first strip with a first inclined side and a second inclined side, and the included angle between the first inclined side and the second inclined side is any value between 70° and 160°. The first belt also has a third surface and a fourth surface disposed opposite to each other, and the third surface and the fourth surface are both located between the first surface and the second surface; Both the third surface and the fourth surface are provided with at least one second groove structure that is recessed into the interior of the first strip, and the depth of the second groove structure is any value between 3 and 30 μm. The second strip has a fifth surface and a sixth surface arranged opposite to each other. The fifth surface is connected to the back of the second battery cell. The thickness of the first coating covering the sixth surface is any value between 2 and 20 μm. The thickness of the first coating covering the sixth surface is controlled by applying a gas with a first preset pressure to the sixth surface during the preparation of the first coating. The first preset pressure is any value between 0.03 and 0.06 MPa.

2. The segmented photovoltaic welding strip according to claim 1, characterized in that, The thickness of the first coating in the first groove structure is less than or equal to 10 μm.

3. The segmented photovoltaic welding strip according to claim 1, characterized in that, The vertical distance between the top of the protruding structure and the bottom of the first groove structure is any value between 40 and 60 μm.

4. The segmented photovoltaic welding strip according to claim 1, characterized in that, The angle between the first hypotenuse and the second hypotenuse is any value between 120° and 130°.

5. The segmented photovoltaic welding strip according to claim 1, characterized in that, The number of the protruding structures is two, and the two protruding structures are symmetrically arranged along the central axis of the first belt.

6. The segmented photovoltaic welding strip according to claim 5, characterized in that, The cross-section of the protruding structure along the thickness direction of the first strip is one of the following: triangular, trapezoidal, semi-circular, semi-elliptical, trapezoidal with arcs on both sides, and triangular with arcs on both sides.

7. The segmented photovoltaic welding strip according to claim 1, characterized in that, The thickness of the first coating covering the sixth surface is any value between 8 and 18 μm.

Images