WO2019237556A1

WO2019237556A1 - Solder strip and assembly for connecting solar cell sheets

Info

Publication number: WO2019237556A1
Application number: PCT/CN2018/107307
Authority: WO
Inventors: 彭福国
Original assignee: 君泰创新（北京）科技有限公司
Priority date: 2018-06-12
Filing date: 2018-09-25
Publication date: 2019-12-19
Also published as: CN208608213U

Abstract

Disclosed are a solder strip and assembly for connecting solar cell sheets. The solder strip for connecting solar cell sheets comprises multiple metal wires, wherein each of the metal wires comprises a connection face and a non-connection face, which extend in the lengthwise direction. The connection face is used for being attached to a solar cell sheet, and the area of a portion, parallel to the connection face, of the non-connection face is smaller than the area of the connection face. The connection faces of metal wires at adjacent ends are oriented opposite each other.

Description

Welding tape and component for solar cell connection

Technical field

The present invention relates to, but is not limited to, the technical field of solar cells, and in particular, to a welding tape and a component for connecting solar cells.

Background technique

With the depletion of conventional fossil fuels, solar energy is undoubtedly the cleanest and most widely available alternative energy source among all sustainable energy sources. Solar cells can convert solar energy into electricity and use it as a power source to drive loads. However, a single solar cell cannot be directly used as a power source, and several solar cells must be connected by welding tapes and tightly sealed to form a photovoltaic cell module for use.

In photovoltaic modules, the welding tape mainly plays the role of connection and conduction. At present, there are mainly two types of welding tapes commonly used in the industry, one is a flat welding tape with a rectangular cross section, and the other is a linear welding tape with a circular cross section. The following issues exist:

For the flat ribbon, because of its large light-shielding area and its surface is flat, the light incident on its surface is totally reflected out of the photovoltaic module, and the solar energy utilization rate is low; for the linear ribbon, its The contact area with the solar cell is small, the reliability of welding is poor, and the aging resistance is poor. Especially when the temperature changes greatly, it is easy to cause disconnection.

Summary of invention

The following is an overview of the topics detailed in this article. This summary is not intended to limit the scope of protection of the claims.

An embodiment of the present invention provides a soldering tape for solar cell connection. The soldering tape for solar cell connection includes a plurality of metal wires.

Each segment of the metal wire includes a connecting surface and a non-connecting surface extending along the length direction. The connecting surface is used for bonding with the solar cell sheet, and the area of the non-connecting surface parallel to the connecting surface is smaller than the connecting surface. Area

The connection faces of adjacent metal lines are oriented in opposite directions.

An embodiment of the present invention further provides a solar cell module, which includes the solar cell connection tape and a plurality of solar cells according to any one of the foregoing embodiments, and a single of the solar cells Connected to the connection surface of a section of metal wire.

After reading and understanding the drawings and detailed description, other aspects can be understood.

Overview of the drawings

FIG. 1 is a schematic structural view of a front view of a welding tape for connecting solar cells according to an embodiment of the present invention; FIG.

FIG. 2 is a schematic left side structural view of the soldering tape for solar cell connection described in FIG. 1; FIG.

FIG. 3 is a schematic plan view of the structure of the soldering tape for solar cell connection described in FIG. 1; FIG.

4 is a schematic structural view of a front view of a soldering tape for connecting solar cells according to another embodiment of the present invention;

FIG. 5 is a schematic left-side view of the soldering tape for solar cell connection described in FIG. 4; FIG.

FIG. 6 is a schematic top plan view of a soldering tape for solar cell connection described in FIG. 4; FIG.

FIG. 7 is a schematic structural view of a front view of a soldering tape for connecting solar cells according to another embodiment of the present invention; FIG.

FIG. 8 is a schematic left side structural view of the soldering tape for solar cell connection described in FIG. 7; FIG.

FIG. 9 is a schematic plan view of the structure of the soldering tape for solar cell connection described in FIG. 7; FIG.

10 is a schematic structural diagram of a solar cell module provided by an embodiment of the present invention;

Fig. 11 is a schematic cross-sectional structure view taken along A-A in Fig. 10.

Correspondence between reference numerals and part names in Figs. 1 to 11:

1-metal wire; 101-connecting surface; 102-non-connecting surface; 2-solar cell.

Elaborate

The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

An embodiment of the present invention provides a soldering tape for solar cell connection. The front view is shown in FIG. 1 or FIG. 4 or FIG. 7, the left view is shown in FIG. 2 or FIG. 5 or FIG. As shown in FIG. 6 or FIG. 9, the soldering tape for solar cell connection includes a plurality of metal wires 1.

Each segment of the metal wire 1 includes a connecting surface 101 and a non-connecting surface 102 extending along the length direction. The connecting surface 101 is used to be attached to the solar cell sheet 2 and the area of the non-connecting surface 102 parallel to the connecting surface 101. Smaller than the area of the connecting surface 101;

The connection surfaces 101 of the adjacent metal lines 1 are opposite to each other, as shown in FIG. 1 or FIG. 4 or FIG. 7.

When the non-connecting surface 102 does not have a portion parallel to the connecting surface 101 (that is, when the non-connecting surface 102 is not parallel to the connecting surface 101), the area of the non-connecting surface 102 that is parallel to the connecting surface 101 is 0. .

Those skilled in the art can understand that the length direction mentioned here is the direction in which the length of the metal wire 1 is located.

Each adjacent metal wire 1 is connected to each other.

The metal wire 1 may include two sections, three sections, or four sections, etc., all of which can achieve the purpose of the present application, and the purpose thereof does not depart from the design concept of the present invention, which is not repeated here, and all belong to the protection scope of the present application. The following description uses a solder tape including metal wires 1 at both ends as an example for description.

The principle of using the welding tape for solar cell connection according to the embodiment of the present invention is as follows:

(1) The connection surface 101 of the metal wire 1 is bonded to the solar cell sheet 2 so that the contact area between the connection surface 101 and the solar cell sheet 2 is increased, and the connection between the metal wire 1 and the solar cell sheet 2 is improved. Sex

(2) The non-connecting surface 102 of the metal wire 1 is set to be neither parallel to the connecting surface 101, or the area of the non-connecting surface 102 parallel to the connecting surface 101 is smaller than the area of the connecting surface 101, so that incident light is illuminated. When reaching the non-connecting surface 102, a part of the incident light can pass between the non-connecting surface 102 and the glass (not shown in the figure) to be irradiated onto the solar cell sheet 2 again to improve the utilization rate of the incident light.

Therefore, when the connecting surfaces 101 of the adjacent metal wires 1 are set to face each other in an opposite direction, the positive electrode and the negative electrode of the adjacent solar cell sheet 2 are connected, so that a plurality of solar cell sheets 2 are connected to increase the The utilization rate also ensures the reliability of the connection between the solder tape and the solar cell 2.

In order to protect the solar cell sheet 2, in the photovoltaic module, a glass may be coated on the upper part of the solar cell sheet 2, and the glass is a glass with high light transmittance.

The following describes the welding tape for solar cell connection according to the embodiment of the present invention:

As for the connection surface 101, the connection surface 101 of each segment of the metal wire 1 is connected to the solar cell sheet 2, and plays a role of connecting the metal wire 1 and the solar cell sheet 2.

In order to achieve a firm connection between the connection surface 101 of each segment of the metal wire 1 and the solar cell 2, the connection surface 101 can be set as a flat surface, so that the contact area between the connection surface 101 and the solar cell 2 is maximized to ensure the connection surface 101 and the solar cell. The firmness of the connection of the sheet 2.

In order to ensure the reliability of the connection between the metal wire 1 and the solar cell sheet 2, in the structural setting, the area of the connection surface 101 of each segment of the metal wire 1 may be greater than or equal to any non-connection surface 102 that is not parallel to the connection surface 101. Area.

This arrangement can ensure that the contact area between the metal wire 1 and the solar cell sheet 2 is the largest, and it is convenient for the metal wire 1 to be connected to the front (light-receiving surface) main grid line or the back (backlight surface) main grid line of the solar cell 2 by welding. , Further improving the reliability of the connection between the connection surface 101 and the solar cell sheet 2.

A plurality of fine grid lines parallel to each other are provided on the front or back of the solar cell chip 2, and a plurality of parallel main grid lines are provided above the fine grid lines. The main grid lines and the fine grid lines are electrically connected and perpendicular to each other. . When solar power generation is performed, the current in the thin grid lines in the solar cell sheet 2 is collected after its main grid line and can be conducted and output through the metal line 1.

In order to ensure the reliability of the connection between the metal wire 1 and the solar cell sheet 2, in the structural setting, the length of each segment of the metal wire 1 may be greater than the length of a single solar cell sheet 2.

In this way, not only can the metal wire 1 and the solar cell sheet 2 have the largest contact area, but because the adjacent solar cell sheet 2 is not directly connected to each other, the adjacent solar cell sheet 2 is connected by the metal wire 1. The positive electrode is connected to the negative electrode, and the metal wire 1 needs to have a part of the connection length between the two adjacent solar cells 2. As shown in FIG. 7, the adjacent solar cells 2 can be avoided due to the too close distance. There was a problem covering each other.

For each segment of metal wire 1, its length is 1 mm to 3 mm longer than the length of the corresponding solar cell sheet 2. The length of each segment of the metal wire 1 can be selectively set according to the size of the solar cell sheet 2, and the value is not specifically limited in the embodiment of the present invention.

For the non-connected surface 102, it can be seen from the literal meaning that the non-connected surface 102 is every other surface other than the connected surface 101.

By setting it to be neither parallel to the connecting surface 101, or the area of the non-connecting surface 102 parallel to the connecting surface 101 being smaller than the area of the connecting surface 101, the incident light will not be incident on the non-connecting surface 102. All the photovoltaic modules are directly reflected, but a part of the incident light can be reflected again between the non-connecting surface 102 and the overlying glass, and then irradiated onto the solar cell sheet 2 again to improve the utilization rate of the incident light.

In an exemplary embodiment of the non-connecting surface 102:

The non-connecting surface 102 may include one or more curved surfaces. The arc surface near the connecting surface 101 is connected to the connecting surface 101. At this time, the non-connecting surface 102 is not parallel to the connecting surface 101.

The non-connecting surface 102 may be an arc surface. The front view is shown in FIG. 1, the left view is shown in FIG. 2, and the top view is shown in FIG. 3.

In this way, the non-connecting surface 102 of the metal wire 1 provided on the upper part of the solar cell sheet 2 is not parallel to the connecting surface 101. When the incident light is irradiated onto the non-connecting surface 102, part of the incident light can pass through the arc surface and cover it. After multiple reflections between the glass, the solar cell 2 is irradiated again, instead of directly reflecting out the photovoltaic module.

In order to improve the utilization ratio of the incident light on the non-connected surface 102, the arc angle corresponding to the arc surface may be 90 ° to 180 °.

In this way, when the incident light is incident on the non-connecting surface 102, it can meet the requirement that part of the incident light is irradiated onto the solar cell sheet 2 after multiple reflections between the arc surface and the glass covered thereon; The contact area of the connection surface 101 is sufficiently large to ensure the firmness of the connection between the metal wire 1 and the solar cell sheet 2.

In the embodiment of the present invention, in the structure shown in FIG. 1, FIG. 2, and FIG. 3, for the non-connecting surface 102 of each segment of the metal wire 1, the non-connecting surface 102 is an arc surface, and the arc surface is The corresponding radian angle is 180 °, that is, the non-connecting surface 101 of each segment of the metal wire 1 is semi-circular; for the overall structure of the multi-segment metal wire 1, as shown in FIG. 2, the welding strip structure can be two semi-circles Symmetric structures formed by opposite shapes.

When the non-connected surface 102 includes multiple curved surfaces, the radian angle corresponding to each curved surface may be the same or different, which is not specifically limited in the embodiment of the present invention.

In an exemplary embodiment of the non-connecting surface 102:

The non-connecting surface 102 may include two or more inclined surfaces, and adjacent two inclined surfaces are connected. The inclined surface near the connecting surface 101 is connected to the connecting surface 101. At this time, the non-connecting surface 102 is not parallel to the connecting surface 101.

For example, when the non-connecting surface 102 is two inclined surfaces, its front view is shown in FIG. 4, the left view is shown in FIG. 5, and the top view is shown in FIG. 6.

The arrangement is such that the non-connecting surface 102 of the metal wire 1 provided on the upper part of the solar cell sheet 2 is not parallel to the connecting surface 101. When the incident light is irradiated onto the non-connecting surface 102, part of the incident light can pass through the inclined surface and its overlying surface. After multiple reflections between the glass, the solar cells 2 are irradiated again, instead of reflecting all the photovoltaic modules directly.

In order to improve the utilization rate of the incident light of the non-connecting surface 102, the angle formed by the two adjacent inclined surfaces may be greater than or equal to 60 °.

In this way, not only can the incident light be incident on the non-connecting surface 102, but the incident light can be irradiated onto the solar cell 2 again after being reflected multiple times between the inclined surface and the glass covered by the incident light. The area of the connection surface 101 of each segment of the metal wire 1 is greater than or equal to the area of the non-connection surface 102 that is not parallel to the connection surface 101, which can ensure that the contact area of the connection surface 101 is large enough to ensure the connection between the metal wire 1 and the solar cell sheet 2. The firmness.

In the structures shown in FIGS. 4, 5 and 6, for the non-connected surface 102 of each segment of the metal wire 1, the non-connected surface 102 is two connected inclined surfaces, and the angle formed by the two inclined surfaces is The angle is 60 °, and the shape of the cross section of the metal wire 1 that is formed by the connecting surface 101 and the non-connecting surface 102 is an equilateral triangle. For the overall structure of the multi-segment metal wire 1, as shown in FIG. 5, the welding tape structure is A symmetrical structure formed by two equilateral triangles facing each other.

The non-connecting surface 102 may be composed of two or more inclined surfaces, and may not be composed of one inclined surface.

In an exemplary embodiment of the non-connecting surface 102:

The cross-section of the metal wire 1 formed by the non-connection surface 102 and the connection surface 101 is trapezoidal. The front view is shown in FIG. 7, the left view is shown in FIG. 8, and the top view is shown in FIG. 9.

Although the non-connection surface 102 includes a portion parallel to the connection surface 101, the area parallel to the connection surface 101 is smaller than the area of the connection surface 101, so that when the incident light is irradiated onto the non-connection surface 102, not all of it is reflected out Photovoltaic modules, but part of the light is irradiated to the part that is not parallel to the connection surface 101. After multiple reflections between this part and the glass it covers, it is again irradiated onto the solar cell sheet 2, which improves the utilization of incident light. .

In the structures shown in FIG. 7, FIG. 8, and FIG. 9, for the non-connecting surface 102 of each segment of the metal wire 1, the shape of the cross-section of the metal wire 1 formed by the non-connecting surface 102 and the connecting surface 101 may be It is a trapezoid; for the overall structure of the multi-segment metal wire 1, as shown in FIG. 8, the solder tape structure is a symmetrical structure formed by two trapezoids facing each other.

The non-connecting surface 102 is designed as a semi-circular arc surface or two adjacent inclined surfaces with an included angle of 60 °. The processing technology is simple, the processing accuracy is low, the production cost is low, and it is easy to promote the application. Therefore, in actual production In processing, the non-connecting surface 102 is mostly the structure shown in FIG. 2 or the structure shown in FIG. 5.

As for the material of the metal wire 1, the metal wire 1 may be any one or more of copper wire, aluminum wire, and alloy wire containing copper or aluminum, so as to ensure that the metal wire 1 has excellent conductive performance.

Due to the convenient access to the copper material and its low price, in the embodiment of the present invention, the material of the metal wire 1 may be copper.

On this basis, in order to protect the metal wire 1 and prevent the metal wire 1 from being oxidized during use, the soldering tape for solar cell connection further includes a protective layer, and the protective layer is laid on the non-connection surface 102.

A protective layer is provided to protect the metal wire 1 and prevent the metal wire 1 from being oxidized.

As for the material selection of the protective layer, as long as the metal material which is more active than the metal wire 1 can be the material for making the protective layer.

For example, the protective layer may be a tin plated layer.

An embodiment of the present invention also provides a solar cell module. The solar cell module includes the above-mentioned welding strip for solar cell connection and a plurality of solar cells 2. A single solar cell 2 is connected to a connection surface 101 of a section of metal wire 1. .

Taking the connection diagram when the semi-circular welding tape of FIGS. 1 to 3 is used as an example, the structural schematic diagram is shown in FIG. 10, and the sectional structural schematic diagram along the A-A line is shown in FIG. 11.

It is possible to connect 10 to 12 solar cells 2 with each solar cell connection welding tape.

Alternatively, it is possible to connect a solar cell connection welding strip in series between any two adjacent solar cells 2, and the two metal wires of the soldering strip are connected to the top of one solar cell 2 and the bottom of another solar cell. In this way, multiple solar cells 2 are connected in series, and n-1 solar cells 2 can be connected in series using n-1 soldering strips.

The above two methods can achieve the purpose of the present application, and the purpose thereof does not depart from the design idea of the present invention, which is not repeated here, and both belong to the protection scope of the present application.

Since the connection surface 101 of the metal wire 1 and the solar cell sheet 2 are bonded, the contact area between the connection surface 101 and the solar cell sheet 2 is increased, the reliability of the connection between the metal wire 1 and the solar cell sheet 2 is improved, and avoidance is avoided. A disconnection occurs between the metal wire 1 and the solar cell sheet 2; since the non-connecting surface 102 of the metal wire 1 is not parallel to the connecting surface 101, or the area of the non-connecting surface 102 parallel to the connecting surface 101 is smaller than the connecting surface The area of 101 makes that when the incident light is irradiated on the non-connected surface 102, a part of the incident light can be reflected on the solar cell sheet 2 after multiple reflections between the non-connected surface 102 and the glass covered thereon without Will be directly reflected out of the photovoltaic module to improve the utilization of incident light.

The beneficial effects of the technical solutions provided by the embodiments of the present invention include at least:

The connection surface of the metal wire and the solar cell are bonded, so that the contact area between the connection surface and the solar cell is increased, and the reliability of the connection between the metal wire and the solar cell is improved; It is set to be neither parallel to the connection surface, or the area of the non-connection surface parallel to the connection surface is smaller than the area of the connection surface, so that when incident light is irradiated on the non-connection surface, part of the incident light can pass through the non-connection surface and above it After multiple reflections between the covered glass, it is again irradiated onto the solar cell to improve the utilization of incident light; the connection faces of adjacent metal wires are connected in opposite directions, so that the positive electrode of the adjacent solar cell and The negative electrodes are connected to realize the connection of multiple solar cells.

The above description is only to facilitate those skilled in the art to understand the technical solutions of the present invention, and is not intended to limit the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

A soldering tape for solar cell connection, the soldering tape for solar cell connection includes a plurality of metal wires (1), wherein:

Each segment of the metal wire (1) includes a connecting surface (101) and a non-connecting surface (102) extending along the length direction. The connecting surface (101) is used for bonding with the solar cell sheet (2) and the non-connecting surface ( 102) the area of the portion parallel to the connection surface (101) is smaller than the area of the connection surface (101);

The connection surfaces (101) of the adjacent metal lines (1) face in opposite directions.
The soldering tape for solar cell connection according to claim 1, wherein the non-connection surface (102) includes one or more curved surfaces, and the curved surface near the connection surface (101) is connected to the connection Face (101) is connected.
The soldering tape for solar cell connection according to claim 2, wherein the arc angle corresponding to the arc surface is 90 ° to 180 °.
The soldering tape for solar cell connection according to claim 1, wherein the non-connection surface (102) includes two or more inclined surfaces, and adjacent two of the inclined surfaces are connected and are close to the connection surface ( The inclined surface of 101) is connected to the connecting surface (101).
The soldering tape for solar cell connection according to claim 4, wherein an angle formed by two adjacent inclined surfaces is greater than or equal to 60 °.
The soldering tape for solar cell connection according to claim 1, wherein the non-connection surface (102) includes two inclined surfaces and a plane, and the plane is located between the two inclined surfaces and is connected to the connection surface. The faces (101) are parallel, and the area of the plane is smaller than the area of the connecting face (101).
The soldering tape for solar cell connection according to claim 1, wherein the area of the connection surface (101) of each segment of the metal wire (1) is greater than or equal to any area that is not parallel to the connection surface (101) The area of the non-connected surface (102).
The soldering tape for solar cell connection according to claim 1, wherein the metal wire (1) includes any one or more of a copper wire, an aluminum wire, and an alloy wire containing copper or aluminum.
The soldering tape for solar cell connection according to claim 1, wherein the soldering tape for solar cell connection further comprises: a protective layer, the protective layer being laid on the non-connection surface (102).
The soldering tape for solar cell connection according to claim 1, wherein the multi-segment metal wire (1) comprises two metal wires (1), two metal wires (1) are connected, and two connection surfaces (101) Relative.
The soldering tape for solar cell connection according to claim 1, wherein the plurality of metal wires (1) are sequentially connected.
The soldering tape for solar cell connection according to claim 11, wherein two connection surfaces (101) or two non-connection surfaces (102) of two adjacent metal wires (1) face each other.
A solar cell module comprising the solar cell connecting tape according to any one of claims 1 to 12 and a plurality of solar cells (2), and a single solar cell ( 2) Connected to the connection surface (101) of a section of metal wire (1).
The solar cell module according to claim 13, wherein the length of each segment of the metal wire (1) is larger than the length of a single said solar cell (2).