CN218677172U - Solder strip and photovoltaic module - Google Patents

Abstract

The embodiment of the application relates to the field of photovoltaic cells, and provides a solder strip and a photovoltaic module, and the solder strip comprises: a copper body layer comprising opposing first and second surfaces; the aluminum layer is at least positioned on the first surface of the copper main body layer; the tin layer is positioned on the surface of one side, far away from the aluminum layer, of the copper main body layer; wherein, in the direction pointing to the aluminum layer along the copper main body layer, the ratio of the thickness of the aluminum layer to the thickness of the copper main body layer is 1.3-2. The solder strip and the photovoltaic module provided by the embodiment of the application are at least beneficial to reducing the manufacturing cost of the solder strip.

Description

Solder strip and photovoltaic module

Technical Field

The embodiment of the application relates to the field of photovoltaic cells, in particular to a solder strip and a photovoltaic module.

Background

The solder strip is used for a welding device of the photovoltaic module and mainly plays a role in connection and conduction. Key technical parameters of the solder strip include solderability, tensile strength, elongation, resistivity. The current commonly used solder strip is prepared on the surface of a copper strip with high elongation, high tensile strength and high conductivity by a hot tin coating method. Along with the improvement of solar cell panel conversion efficiency, through welding the current of taking inside bigger and bigger, consequently just require to weld the conducting area who takes and constantly increase, but along with the increase of welding the area thickness, the cost also can increase, consequently need provide a low cost, high conducting area's welding area to solve present solar photovoltaic technical field's problem.

It can be seen that the existing solder strips still have many defects and need to be improved.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a solder strip and a photovoltaic module, which at least facilitate reducing the manufacturing cost of the solder strip.

According to some embodiments of the present application, in one aspect, there is provided a solder strip, including: a copper body layer comprising opposing first and second surfaces; the aluminum layer is at least positioned on the first surface of the copper main body layer; the tin layer is positioned on the surface of one side, far away from the aluminum layer, of the copper main body layer; wherein, in the direction pointing to the aluminum layer along the copper main body layer, the ratio of the thickness of the aluminum layer to the thickness of the copper main body layer is 1.3-2.

In some embodiments, the copper body layer extends along a first direction, and the aluminum layers are alternately arranged on the first surface and the second surface of the copper body layer along the first direction; and the orthographic projection of the aluminum layer on the first surface and the aluminum layer on the second surface on the first surface or the second surface of the copper body layer is at least partially not overlapped.

In some embodiments, an orthographic projection of the tin layer on the first surface or the second surface coincides with an orthographic projection of the aluminum layer on the first surface or the second surface.

In some embodiments, the aluminum layer covers the first surface and the tin layer covers the second surface.

In some embodiments, the aluminum layer covers the first surface, and the plurality of tin layers are disposed at intervals on the second surface.

In some embodiments, the second surface further has an insulating layer filling the gap between the tin layers.

In some embodiments, the copper body layer has a thickness in the range of 50 to 150 μm; the thickness of the aluminum layer ranges from 200 to 350 μm.

In some embodiments, the solder strip has a thickness in the range of 300-400 μm.

In some embodiments, the solder strip further comprises: the nickel layer covers one side surface of the aluminum layer far away from the copper main body layer, and the orthographic projection of the nickel layer on the first surface is superposed with the orthographic projection of the aluminum layer on the first surface.

According to some embodiments of the present application, there is also provided in another aspect a photovoltaic module, including: the battery string comprises battery pieces which are connected in sequence, and the adjacent battery pieces are connected through the welding strip in any one of the above embodiments.

The technical scheme provided by the embodiment of the application has at least the following advantages: through setting up the aluminium lamination at the at least first surface of copper bulk layer, set up the tin layer and lie in the copper bulk layer and keep away from the side surface of aluminium lamination, can make the whole condition that is unchangeable at relative thickness of the area that welds that copper bulk layer, aluminium lamination and tin layer constitute jointly, the thickness of copper in the minimize welding area to reduce the quantity of copper in the welding area, reduce the manufacturing cost who welds the area, reduce the weight that welds the area. Because the aluminum layer and the copper main body layer have relatively close conductivity, the specific gravity of the aluminum layer is lower than 1/3 of that of the copper main body layer, and the price of aluminum is lower than that of copper, the aluminum layer arranged in the welding strip can be beneficial to reducing the manufacturing cost of the welding strip, and the overall quality of the welding strip can be reduced to reduce the transportation cost of the welding strip; in addition, the aluminum layer is used as a good conductor, has higher flexibility than the copper main body layer, and can better relieve stress generated by heat circulation than the copper main body layer, so that the service life of the welding strip is greatly prolonged. The tin layer is positioned on the surface of one side, far away from the aluminum layer, of the copper main body layer, the copper main body layer can be prevented from being oxidized, and low-temperature welding of the welding strip and other devices can be facilitated due to the fact that tin has good conductive performance and a low melting point. In addition, the aluminum layer and the copper main body layer can form a parallel circuit, so that the resistance and the resistance loss of the welding strip are reduced, and the output power of the assembly is increased, but in the direction pointing to the aluminum layer along the copper main body layer, the ratio of the thickness of the aluminum layer to the thickness of the copper main body layer needs to be controlled within the range of 1.3-2, so that the phenomenon that the resistance of the welding strip is too large due to the fact that the thickness of the aluminum layer is too thick is avoided, and the heat productivity of the welding strip in the using process is further reduced.

Drawings

One or more embodiments are illustrated by corresponding figures in the drawings, which are not to be construed as limiting the embodiments, unless expressly stated otherwise, the drawings are not to scale; in order to more clearly illustrate the embodiments of the present application or technical solutions in the conventional technology, the drawings needed to be used in the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 to 11 are schematic structural views of various solder strips according to an embodiment of the present application.

Detailed Description

As can be seen from the background, the existing solder strips still have a number of drawbacks and need to be improved.

Analysis finds that in related processes, most of solder strips are formed by tin plating on the surfaces of pure copper, the conductivity of copper is high, soldering tin is mainly used for preventing the solder strips from being oxidized, the cost of the solder strips with the copper as a main body is high, and the mass of the solder strips is large, so that the cost of batch transportation is increased. In order to reduce the manufacturing cost of the solder strip, the related art replaces pure copper with copper-clad aluminum alloy as the low-current solder strip in the photovoltaic industry, but the copper-clad aluminum still needs to consume more copper.

According to some embodiments of the present application, an embodiment of the present application provides a solder strip, which at least facilitates reducing manufacturing costs of the solder strip.

Embodiments of the present application will be described in detail below with reference to the accompanying drawings. However, it will be appreciated by those of ordinary skill in the art that in the examples of the present application, numerous technical details are set forth in order to provide a better understanding of the present application. However, the technical solution claimed in the present application can be implemented without these technical details and various changes and modifications based on the following embodiments.

Fig. 1 to 11 are schematic structural diagrams of various solder strips provided in an embodiment of the present application, and the solder strips provided in the embodiment will be described in detail below with reference to the accompanying drawings, specifically as follows:

referring to fig. 1, a solder strip 100 includes: a copper body layer 101, the copper body layer 101 including opposing first and second surfaces 111, 121; an aluminum layer 102, the aluminum layer 102 being at least located on the first surface 111 of the copper body layer 101; a tin layer 103, wherein the tin layer 103 is positioned on the surface of the copper main body layer 101, which is far away from the aluminum layer 102; wherein, in a direction pointing to the aluminum layer 102 along the copper body layer 101, a ratio of a thickness of the aluminum layer 102 to a thickness of the copper body layer 101 is 1.3 to 2, for example, the ratio of the thickness of the aluminum layer 102 to the thickness of the copper body layer 101 may be 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, or 2.0.

By arranging the aluminum layer 102 on at least the first surface 111 of the copper main body layer 101 and arranging the tin layer 103 on the surface of the copper main body layer 101 on the side away from the aluminum layer 102, the thickness of copper in the solder strip 100 can be reduced as much as possible under the condition that the relative thickness of the whole solder strip 100 formed by the copper main body layer 101, the aluminum layer 102 and the tin layer 103 is inconvenient, so that the using amount of copper in the solder strip 100 is reduced, the manufacturing cost of the solder strip 100 is reduced, and the weight of the solder strip 100 is reduced. Because the aluminum layer 102 and the copper main body layer 101 have relatively close conductivity, the specific gravity of the aluminum layer 102 is lower than 1/3 of that of the copper main body layer 101, and the price of aluminum is lower than that of copper, the aluminum layer 102 arranged in the solder strip 100 can be beneficial to reducing the manufacturing cost of the solder strip 100, and simultaneously, the overall mass of the solder strip 100 is reduced to reduce the transportation cost; in addition, the aluminum layer 102, which is a good conductor, has higher flexibility than the copper body layer 101, and can better alleviate stress generated by heat cycle than the copper body layer 101, thereby greatly prolonging the service life of the solder strip 100. The tin layer 103 is located on the surface of the copper main body layer 101 away from the aluminum layer 102, so as to prevent the copper main body layer 101 from being oxidized, and since tin has better conductivity and lower melting point, low-temperature welding of the welding strip 100 and other devices can be facilitated. In addition, the aluminum layer 102 and the copper main body layer 101 may form a parallel circuit, so as to reduce the resistance and the resistance loss of the solder strip 100 and increase the output power of the device, but in the direction from the copper main body layer 101 to the aluminum layer 102, the ratio of the thickness of the aluminum layer 102 to the thickness of the copper main body layer 101 needs to be controlled within the range of 1.3-2, so as to avoid the excessive resistance of the solder strip 100 caused by the excessive thickness of the aluminum layer 102, and further reduce the heat generation amount of the solder strip 100 in the use process.

For the copper body layer 101, the material of the copper body layer 101 may be selected from pure copper, oxygen-free copper or red copper.

For the aluminum layer 102, the aluminum layer 102 and the first surface 111 of the copper body layer 101 may be connected by electroplating or soldering.

In some embodiments, the electroplating method may be that the aluminum layer 102 is used as a cathode, the aluminum layer 102 is placed in an electrolyte solution with copper ions, and the copper ions in the electrolyte solution are deposited on the surface of the aluminum layer 102 by electrolysis to form a copper body layer 101.

In some embodiments, the welding method may be to weld the first surface 111 of the copper body layer 101 and the aluminum layer 102 by argon arc welding.

For the tin layer 103, the tin layer 103 may be joined to the copper body layer by hot dipping.

Referring to fig. 2, in some embodiments, the copper body layer 101 extends along a first direction X, and the aluminum layers 102 are alternately disposed on the first surface 111 and the second surface 121 of the copper body layer 101 along the first direction X; and the aluminum layer 102 on the first surface 111 and the aluminum layer 102 on the second surface 121 do not overlap at least partially in an orthographic projection on the first surface 111 or the second surface 121 of the copper body layer 101.

By alternately disposing the aluminum layers 102 on the first surface 111 and the second surface 121 of the copper body layer 101, the corresponding tin layers 103 can be alternately disposed on the first surface 111 and the second surface 121 of the copper body layer 101, so that the solder strip 100 has the tin layers 103 disposed at intervals on both side surfaces, and the first surface 111 or the second surface 121 of the copper body layer 101 can be soldered to other devices through the tin layers 103.

For example, referring to fig. 3, when the battery pieces 104 are connected in series or in parallel, and the adjacent battery pieces 104 need to be connected by the solder strip 100 between the front surface of one battery piece 104 and the back surface of the other battery piece 104, the tin layer 103 may be located between the first surface 111 of the copper main body layer 101 and the front surface of the battery piece 104, and may also be located between the second surface 121 of the copper main body layer 101 and the back surface of the battery piece 104, so that the solder strip 100 does not need to be turned over to connect the front surface of the adjacent battery piece 104 and the back surface of the other battery piece 104.

For the copper body layer 101 between the cell sheets 104, referring to fig. 4, in some embodiments, the first surface 111 and the second surface 121 of the copper body layer 101 between the cell sheets 104 may both be provided as a tin layer 103; referring to fig. 5, in some embodiments, the first surface 111 and the second surface 121 of the copper body layer 101 between the battery pieces 104 may both be provided as an aluminum layer 102; referring to fig. 6, in some embodiments, the edges of the aluminum layer 102 and the tin layer 103 on the first surface 111 and the second surface 121 of the copper body layer 101 between the battery pieces 104 may be extended to be connected to each other.

In some embodiments, the solder strips 100 between the battery pieces 104 may be flattened so that the solder strips 100 between the battery pieces 104 are thin and flexible, and when the adjacent battery pieces 104 are connected, the stress between the battery pieces 104 may be effectively reduced, and the battery pieces 104 are prevented from cracking or subfissure.

Further, referring to fig. 7, in some embodiments, an orthographic projection of the tin layer 103 on the first surface 111 or the second surface 121 coincides with an orthographic projection of the aluminum layer 102 on the first surface 111 or the second surface 121. That is, the aluminum layer 102 and the tin layer 103 on the two side surfaces of the copper main body layer 101 are opposite, and the arrangement of the aluminum layer 102 and the tin layer 103 on the other surface of the copper main body layer 101 can be determined only by the first surface 111 or the second surface 121 of the copper main body layer 101, without repeatedly turning the solder strip 100 for identification.

Referring to fig. 8, in some embodiments, the aluminum layer 102 covers the first surface 111 and the tin layer 103 covers the second surface 121. The aluminum layer 102 and the tin layer 103 may cover both side surfaces of the copper body layer 101 to prevent the copper body layer 101 from being exposed to oxidation.

Referring to fig. 9, in some embodiments, the aluminum layer 102 covers the first surface 111, and the tin layers 103 are disposed at intervals on the second surface 121. That is, the tin layer 103 may be disposed at a position where the solder strip 100 and other devices need to be soldered, and the spacing of the tin layer 103 may reduce the amount of tin used, thereby reducing the manufacturing cost of the solder strip 100, compared to the case where the tin layer 103 needs to cover the copper main body layer 101 on the front side.

In the drawings provided in this embodiment, the tin layers 103 disposed at 3 intervals on the second surface 121 of the copper body layer 101 are taken as an example, and the number of the tin layers 103 on the second surface 121 of the copper body layer 101 is not limited. In other embodiments, the second surface 121 of the copper body layer 101 may have 10, 20, 50, 80, or 100 spaced tin layers 103.

Further, referring to fig. 10, in some embodiments, the second surface 121 further has an insulating layer 105, and the insulating layer 105 fills the gap between the tin layers 103. The insulating layer 105 fills the gap between the tin layers 103, so that the exposed copper main body layer 101 is covered by the insulating layer 105, the tin layers 103 and the aluminum layer 102, and the copper main body layer 101 is prevented from being oxidized; meanwhile, the insulating layer 105 can insulate the part of the solder strip 100 not provided with the tin layer 103 from other devices, so that electric leakage caused by electric contact between the solder strip 100 and other devices is avoided.

In some embodiments, the thickness of the copper body layer 101 in a direction along the copper body layer 101 towards the aluminum layer 102 ranges from 50 to 150 μm, for example, the thickness of the copper body layer 101 may be 50 μm, 60 μm, 80 μm, 100 μm, 120 μm, 130 μm, or 150 μm; the thickness of the aluminum layer 102 ranges from 200 to 350 μm, for example, the thickness of the aluminum layer 102 may be 200 μm, 230 μm, 250 μm, 280 μm, 300 μm, 320 μm, 340 μm, or 350 μm. It can be understood that, in the case of a constant thickness of the solder strip 100, the thicker the copper main body layer 101, the thinner the corresponding aluminum layer 102, the higher the copper content required, and the higher the manufacturing cost of the solder strip 100; as the thickness of the copper body layer 101 becomes thinner and the thickness of the aluminum layer 102 becomes thicker, the resistance of the entire solder strip 100 increases, and the solder strip 100 is likely to generate heat during use, which affects the usability of the solder strip 100. Therefore, the thicknesses of the copper body layer 101 and the aluminum layer 102 need to be adjusted within a certain range to meet the requirement of reducing the manufacturing cost of the solder strip 100, and simultaneously avoid the resistance of the solder strip 100 from increasing due to the excessively thick thickness of the aluminum layer 102.

In some embodiments, the tin layer 103 has a thickness of 30 μm to 50 μm in a direction along the copper body layer 101 towards the tin layer 103, for example, the tin layer 103 may have a thickness of 30 μm, 35 μm, 40 μm, 45 μm, or 50 μm. It will be appreciated that the thickness of the tin layer 103 has less of an effect on the thickness of the solder strip 100, as long as the tin layer 103 covers the copper body layer 101 and facilitates soldering of the solder strip 100 to other devices.

Referring back to fig. 7, when the aluminum layers 102 are alternately disposed on the first surface 111 and the second surface 121 of the copper main body layer 101, in some embodiments, the thickness of the tin layer 103 between adjacent aluminum layers 102 may be increased to be the same as the thickness of the aluminum layer 102, so as to avoid a step at the junction of the aluminum layer 102 and the tin layer 103 on the surface of the solder strip 100 from affecting the smoothness of the surface of the solder strip 100, thereby improving the use effect of the solder strip 100.

In some embodiments, the thickness of the solder strip 100 in a direction perpendicular to the first surface 111 or the second surface 121 is in a range of 300-400 μm, for example, the thickness of the solder strip 100 may be 300 μm, 320 μm, 350 μm, 370 μm, or 400 μm. It will be appreciated that the solder strip 100 is used to solder devices to make electrical connections between devices, the thicker the thickness of the solder strip 100, the higher the cost of manufacturing the solder strip 100; the thinner the thickness of the solder strip 100 is, the less the solder strip 100 is, the more the solder strip 100 is not conductive. Therefore, the thickness of the solder strip 100 needs to be selected within a certain range, and the manufacturing cost of the solder strip 100 is reduced as much as possible on the premise of meeting the use requirement of the solder strip 100.

Referring to fig. 11, in some embodiments, the solder strip 100 further includes: a nickel layer 106, wherein the nickel layer 106 covers the surface of the aluminum layer 102 far away from the copper body layer 101, and the orthographic projection of the nickel layer 106 on the first surface 111 is coincident with the orthographic projection of the aluminum layer 102 on the first surface 111. That is, by covering the nickel layer 106 on the surface of the aluminum layer 102 away from the copper body layer 101, the exposed surface of the aluminum layer 102 can be prevented from being oxidized, and thus the resistance of the solder strip 100 can be prevented from increasing. In addition, the nickel layer 106 can enable the surface of the solder strip 100 to have higher light reflectivity, and when the solder strip 100 is located on the front side of the cell, the light utilization rate of the photovoltaic module can be improved.

In some embodiments, nickel layer 106 may be formed by electrochemical deposition from an electroplating solution containing a solderable plating metal element.

According to the solder strip provided by the embodiment of the application, the aluminum layer 102 is arranged on at least the first surface 111 of the copper main body layer 101, and the tin layer 103 is arranged on the surface of the side, away from the aluminum layer 102, of the copper main body layer 101, so that the thickness of copper in the solder strip 100 can be reduced as much as possible under the condition that the relative thickness of the whole solder strip 100 formed by the copper main body layer 101, the aluminum layer 102 and the tin layer 103 is not changed, the consumption of copper in the solder strip 100 is reduced, the manufacturing cost of the solder strip 100 is reduced, and the weight of the solder strip 100 is reduced. Because the aluminum layer 102 and the copper main body layer 101 have relatively close conductivity, the specific gravity of the aluminum layer 102 is lower than 1/3 of that of the copper main body layer 101, and the price of aluminum is lower than that of copper, the aluminum layer 102 arranged in the solder strip 100 can be beneficial to reducing the manufacturing cost of the solder strip 100, and simultaneously, the overall mass of the solder strip 100 is reduced to reduce the transportation cost; in addition, the aluminum layer 102, which is a good conductor, has higher flexibility than the copper body layer 101, and can better alleviate stress generated by heat cycle than the copper body layer 101, thereby greatly prolonging the service life of the solder strip 100. The tin layer 103 is located on the surface of the copper main body layer 101 away from the aluminum layer 102, so as to prevent the copper main body layer 101 from being oxidized, and since tin has better conductivity and lower melting point, low-temperature welding of the welding strip 100 and other devices can be facilitated. In addition, the aluminum layer 102 and the copper main body layer 101 may form a parallel circuit, so as to reduce the resistance and the resistance loss of the solder strip 100 and increase the output power of the device, but in the direction from the copper main body layer 101 to the aluminum layer 102, the ratio of the thickness of the aluminum layer 102 to the thickness of the copper main body layer 101 needs to be controlled within the range of 1.3-2, so as to avoid the excessive resistance of the solder strip 100 caused by the excessive thickness of the aluminum layer 102, and further reduce the heat generation amount of the solder strip 100 in the use process.

According to some embodiments of the present application, another embodiment of the present application provides a photovoltaic module, which is soldered by using the solder strip provided in the above embodiments. It should be noted that, for the same or corresponding parts as those in the foregoing embodiments, reference may be made to the corresponding description of the foregoing embodiments, and detailed description will not be provided below.

A photovoltaic module comprising: the battery string comprises battery pieces which are connected in sequence, and the adjacent battery pieces are connected through the welding strip in any one of the above embodiments.

In some embodiments, the number of the solder strips on each cell is more than or equal to 2, so that when two adjacent cells are laminated, the pressure of the contact part of the cell and the solder strips can be reduced, the deformation and hidden cracking possibility of the cell in the laminating process is reduced, and the yield of the photovoltaic module is improved.

Furthermore, a plurality of welding strips are distributed between two adjacent battery pieces at equal intervals, so that the stress of the battery pieces is more uniform in the laminating process, the possibility of deformation and hidden cracking of the battery pieces in the laminating process is reduced, and the yield of the photovoltaic module is improved.

In some embodiments, the number of the battery strings is at least two, and the battery strings are electrically connected in parallel and/or in series.

In some embodiments, the photovoltaic module may further include an encapsulation layer for covering a surface of the cell string. For example, encapsulation layers may be provided on the front and back of the cell string.

In some embodiments, the material of the encapsulation layer includes, but is not limited to, EVA, POE, or PET adhesive film.

Further, in some embodiments, the photovoltaic module may further include a cover plate, where the cover plate is used to cover a surface of the encapsulation layer away from the battery string, and the cover plate may be made of a material with good light transmittance, so as to protect the photovoltaic module and not affect light.

In some embodiments, the material of the cover plate includes, but is not limited to, glass, plastic, and the like.

It will be understood by those of ordinary skill in the art that the foregoing embodiments are specific examples for carrying out the present application, and that various changes in form and details may be made therein without departing from the spirit and scope of the present application in practice.

Claims (10)

1. A solder strip, comprising:

a copper body layer comprising opposing first and second surfaces;

an aluminum layer at least on the first surface of the copper body layer;

the tin layer is positioned on the surface of one side, away from the aluminum layer, of the copper main body layer;

wherein a ratio of a thickness of the aluminum layer to a thickness of the copper body layer in a direction toward the aluminum layer along the copper body layer is 1.3 to 2.

2. The solder ribbon of claim 1, wherein the copper body layer extends in a first direction in which the aluminum layers are alternately disposed on the first and second surfaces of the copper body layer; the aluminum layer on the first surface and the aluminum layer on the second surface have at least partial non-overlapping orthographic projections on the first surface or the second surface of the copper body layer.

3. Solder strip according to claim 2, characterized in that the orthographic projection of the tin layer on the first surface or the second surface coincides with the orthographic projection of the aluminium layer on the first surface or the second surface.

4. Solder strip according to claim 1, characterized in that the aluminium layer covers the first surface and the tin layer covers the second surface.

5. The solder strip of claim 1, wherein the aluminum layer covers the first surface and the plurality of tin layers are spaced apart on the second surface.

6. The solder strip of claim 5, wherein the second surface further has an insulating layer filling gaps between the tin layers.

7. The solder strip of claim 1, wherein the copper body layer has a thickness in the range of 50-150 μ ι η; the thickness of the aluminum layer ranges from 200 to 350 mu m.

8. The solder strip of claim 7, wherein the solder strip has a thickness in the range of 300-400 μm.

9. The solder strip of claim 1, further comprising: the nickel layer covers one side surface of the aluminum layer far away from the copper main body layer, and the orthographic projection of the nickel layer on the first surface is superposed with the orthographic projection of the aluminum layer on the first surface.

10. A photovoltaic module, comprising:

a battery string comprising sequentially connected battery pieces, adjacent battery pieces being connected by a solder ribbon as claimed in any one of claims 1 to 9.

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