MX2011005821A

MX2011005821A - Method for producing a photovoltaic module and photovoltaic module.

Info

Publication number: MX2011005821A
Application number: MX2011005821A
Authority: MX
Inventors: Jens Kalmbach; Andreas Reichle
Original assignee: Schmid Technology Systems Gmbh
Priority date: 2008-12-05
Filing date: 2009-11-27
Publication date: 2011-07-13
Also published as: IL213336A0; SG171878A1; CN102246322B; DE102008063551A1; EP2353185A2; CN102246322A; WO2010063412A3; TW201029214A; WO2010063412A2; CA2745700A1; AU2009321754A1; KR20110114533A

Abstract

The invention relates to a method for producing a photovoltaic module having a plurality of solar cells which are connected in series. Said series connection comprises two connections. The connections of a plurality of series connections are combined into a connecting device. A plurality a homopolar connections are connected to each other by way of transverse contact wires. They are guided next to the solar cells over a carrier glass on the front side and beneath a film on the back side, wherein the film on the back side extends over the solar cells and the transverse contact wires. The transverse contact wires are bent together for greater thickness or folded away from the carrier glass on the front side and guided through cutouts in the film on the back side. Thus they protrude over said film on the back side for subsequent electrical connection.

Description

METHOD TO PRODUCE A PHOTOVOLTAIC MODULE AND MODULE PHOTOVOLTAIC Field of application and previous technique The invention relates to a method for producing or electrically connecting a photovoltaic module having a large variety of solar cells according to the preamble of claim 1 and to the photovoltaic module.

During the production of a photovoltaic module composed of a wide variety of solar cells, often the so-called series or chains of several solar cells are placed on a glass carrier of the front side next to each other with the interposition of a film laminadora, to be precise, usually several chains of solar cells next to each other. These chains are longitudinally connected by contact to contacts on the front side and the rear side for the two poles of the electrical connections, to be conveniently required a wide variety of connections on both the front side and the rear side. The transverse contact cables extend on a front side of the solar cells, these transverse contact wires being connected to the connections on the front side and the rear side of the solar cells. The transverse contact cables lead together to a connection device which is subsequently adapted, for example a so-called junction box. The last one is used for the electrical connection of the entire photovoltaic module. The solar cells in turn then have an additional laminated film placed on top of them and, finally, a film of the rear side is placed on said cells. This is followed by the lamination of the photovoltaic module and then the adaptation of the connection device as an electrical contact connection to the transverse contact cables.

At present, the transverse contact cables are bent up to 90 ° from the front edge of the solar cells and placed on the rear side of the solar cells for the purpose of the electrical connection subsequent to the connection device. For this purpose, the transverse contact cables have to be manually guided in a complex manner through cuts in the back side film and the laminating film in the rear side of the solar cells. This is unfavorable.

Objective and how it is achieved The invention is based on the object of providing a method mentioned in the introduction and a corresponding photovoltaic module, with which the problems in the prior art can be eliminated and, in particular, the possibility of an electrical connection to a photovoltaic module can be obtained. which is simple to carry out and is easily automated.

This object is achieved by means of a method having the features of Claim 1 and a photovoltaic module having the features of Claim 11. The favorable and preferred configurations of the invention are the central theme of the additional claims and are explained below. very detailed. Some of the following characteristics are described only for the method or only for the photovoltaic module. Regardless of this, however, they propose to be applicable to both the method and the photovoltaic module. The wording of the claims is incorporated for explicit reference in the content of the description.

According to the invention, several connections of identical polarity of the solar cells are connected to each other by means of the transverse contact cables and the transverse contact cables are guided along or in front of the solar cells above a glass carrying the Front side In this case, they have favorable influence on the carrier glass or on a laminating film directly on the carrier glass. In addition, the transverse contact cables are guided under the back side film, which also extends above the solar cells. The transverse contact wires are bent together or folded upwards together in such a way that they have a thickness greater than or multiple of their own thickness in accordance with the folding and protrude or extend from the carrier glass or protrude above it. These protruding bent regions of the transverse contact cables are guided through cuts previously produced in the back side film, if appropriate also in a laminating film placed between the solar cells and the back side film. As a result of the larger thickness, the transverse contact wires protrude above the film on the back side or above its surface.

These regions folded or favorably bent are still within the cut of the films, so that they do not have to be specially displaced or driven. The electrical connection before mentioned, which will be described in detail below, can then be easily performed in these folded or bent regions. What can be achieved as a result of the transverse contact wires that are bent together or folded upwards is that they automatically protrude above the surface of the back side film and can be easily reached for electrical connection.

In a favorable configuration of the invention, a transverse contact wire is folded up at least once, such that the thickness is at least doubled. In a particularly favorable manner, it is bent or folded up two or three times. Multiple folding can be carried out at least partially with a folding by winding, whereby it is possible to start folding from the end of the transverse contact wire. However, this crucially depends on a technological optimization of folding in terms of production. In this case, in a further configuration of the invention, it can be arranged that the transverse contact cables remain along their general longitudinal orientation including during folding and in the folded state, that is to say that no bends are made towards the side. The number of examples of folding also depends on the thickness of the laminating film and the film of the rear side. As a favorable thickness of a laminating film, approximately 0.4 mm can be taken as the base and a little less for the back side film. A transverse contact wire, which is favorably a tinned wire, which can be made particularly advantageously of copper, can have a thickness of 0.3 mm to 0.5 mm. Therefore, a sufficient height and projection of the folded or bent regions above the films can be achieved with two or even better with three bends. The width of a transverse contact wire can be at least 3 mm, advantageously about 5 mm.

In a favorable configuration of the invention, the transverse contact cables are guided near the leading edges of the front solar cells and in particular parallel to each other, including those of connections of different polarity. In a particularly favorable manner, the transverse contact cables extend on the narrow sides of the photovoltaic module, in such a way that they can be kept shorter. Transverse contact cables of different polarity should have a distance of a few millimeters with respect to each other.

In another favorable configuration of the invention, a single connection device can be provided per photovoltaic module with a large variety of regions of folded transverse contact cables. If a photovoltaic module has, for example, six aforementioned series of solar cells, then it is considered convenient to provide two of these connection devices. The specific solar cells or series can be provided by connection device or both connection devices are as if they were parallel to each other and are respectively connected to all the solar cells.

By connecting device, which in each case has both poles of the solar cells or the electrical connections of said cells, two folded regions of the cables can be favorably provided. transversal contact per pole. These can be guided from the left and from the right to the connection device. In this case, it is also possible to compensate the folded regions in relation to each other in such a way that they are spatially separated and can not be confused. A) Yes, by way of example, the transverse contact cables connected to contacts on the front side of the solar cells can in each case be extended very close to the solar cells and the others at a slightly larger distance from said cells. The transverse contact wires which are guided more closely to the solar cells can, if they reach the connection device from the left and right, be guided closer to each other than the other transverse contact cables.

In another development of the invention, the cuts are produced, for example, by being stamped, in the rear side film, in particular also in the laminating film placed on the solar cells on the rear side, before laying. Favorably, the cuts have a rectangular or square shape. They should be significantly larger than the folded regions of the transverse contact wires themselves in order to compensate the tolerances and, especially in the case of the laminating film, in order to compensate for the propagation of area during the rolling. By way of example, they may have approximately twice the length of said regions and a width that is a multiple of the width of said regions. The cuts in the film of the backside and the film laminadora should be one on top of the other.

It is proposed that a projection of the transverse contact cables bent or folded upwards above the upper side of the Rear side film is at least 0.1 to 0.2 mm. In this way a reliable electrical connection is possible, under certain circumstances even by means of a connection by pressure contact in the connection device. This is done after the lamination of the photovoltaic module. The connecting device can then be fixed to the edge of the carrier glass or of an edge profile connected to said device. The fixing is also possible by adhesive bonding to the film of the rear side. For this purpose, the junction box can have a cover with closure, for example, which is placed after the fixing of the connection box and the production of the electrical connections to the transverse contact cables. An electrical connection of the connection device to the transverse contact cables can be made by means of aforementioned pressure contacts or the like which are present. For a reliable contact connection, however, bar welding or normal welding is recommended in order to avoid later contact connection problems.

These and other characteristics arise not only from the claims but also from the description and the drawings, wherein the individual characteristics may be embodied in each case by themselves or as a great variety in the form of secondary combinations in an embodiment of the invention and in other fields and may constitute favorable and inherently protectable realizations for which protection is claimed here. The subdivision of the application into individual sections and subtitles does not restrict the general validity of the statements made in accordance with said request.

BRIEF DESCRIPTION OF THE DRAWINGS An exemplary embodiment of the invention is schematically illustrated in the drawings and is explained in more detail below. In the drawings: Figure 1 shows an oblique view from below of the solar cells with transverse contact cables which are bent upwards in various forms in their end regions, Figure 2 shows a plan view of the arrangement of Figure 1 of the rear side and Figure 3 shows a side view of the upwardly folded end regions of the transverse contact cables in a precise manner.

Detailed description of the exemplary embodiments Figure 1 illustrates, in an oblique view from below, how a large variety of solar cells 11 are provided, represented by way of example by two of these solar cells. They have front contacts 12 on the front sides 13, as is generally known. Extending above the front contacts 12 are the collective contacts 15 formed by flat wires, which protrude a little beyond the side edges of the solar cells 11. In Figure 1, in the direction of the collective contacts 15, the cells Solar cells 11 are provided in the form of so-called arrays, ie, by way of example, six to ten solar cells 11 are connected as a chain. Several series in turn are arranged along one another, for example four or six.

The transverse contact cables 17 extend in front of the solar cells 11, wherein the transverse contact cables 17a extend very close to the solar cells 11, for example at a distance of a few millimeters. The transverse contact cables 17b extend parallel to said cells and are identically formed, in particular, and have a distance of a few millimeters with respect to the transverse contact cables 17a.

The folded regions 19a and 19b are provided at the illustrated ends of the transverse contact wires 17, which will be explained very in detail with respect to Figure 3. They are formed as if they were the end of the transverse contact wires. It can also be discerned that the ends or folded regions 19a of the transverse contact cables 17a are much closer to each other than the folded regions 19b of the transverse contact cables 17b.

It can be seen from Figure 1 and also Figure 2 that the collective contacts 15 are connected and connected by contact to the transverse contact wires 17a, preferably by bar welding or normal welding. In this way, so to speak, one of two electrical connections to the solar cells 11 can be provided by means of the transverse contact cables 17a which are connected left and right to additional collective contacts 15 of the front contacts 12 of the Solar cells 11. The illustration shows no contacts of the rear side in the solar cells 11, which pass to the transverse contact cables 17b extending a little further and are electrically connected or soldered to said cells. However, a person with experience in the technique can imagine and perform it easily.

It can also be seen from the plan view of Figure 2 how a leading edge of a laminating film 24 protrudes a little beyond the transverse contact wires 17b and thus covers them well. The leading edge of said laminating film 24 corresponds to the leading edge of a carrier glass 22 illustrated in FIG. 3, over which the solar cells 11 are placed on their front sides 13 with the interposition of an additional laminating film (not illustrated). ). As it were, it is a lateral edge of the entire finished photovoltaic module 30, whose assembly is illustrated schematically in Figure 3.

Figure 2 mainly illustrates also how a backside film 26 is provided with cuts 27 before it is placed on the back sides of the solar cells 1 1 and the transverse contact wires 17. In this case, the cuts 27a are a little farther from a side edge and closer to each other than cuts 27b. As can be discerned from Figure 3, the laminating film 24 and the backside film 26 are placed on the rear side of the solar cells 11, the laminating film 24 also having cuts corresponding to those of the backside film 26. During the positioning in accordance with Figure 3, the folded regions 19a protrude through the cuts 27a in the backside film 26 and the corresponding cuts in the laminating film 24. Also, the folded regions 19b protrude through the cuts 27b in the film in laminator 24 and the film in the back 26. As can be discerned of Figure 2, it can be arranged that the cuts 27 are a little larger than the folded regions 19, but not much larger.

It can be seen from Figure 3 that the transverse contact cables 17 are folded three times in the folded regions 19, that is, they have four times the thickness of the transverse contact cable. The folding is carried out in such a way that an end region of the transverse contact cable having a length of one to two centimeters, for example, be reciprocally placed twice on top of each other and then folded up away from the end. Other folding or bending is also possible, as explained at the beginning. In a favorable manner, all the folded regions 19 have the same height. This means that a uniform folding operation can be carried out and therefore the electrical connection devices can be represented identically in each case, which, although not illustrated here, can easily be realized by persons skilled in the art.

It can be discerned precisely from the figures how, after the transverse contact cables 17 have been folded to form the folded regions 19, the latter protrude in accordance with Figure 3 and, during the placement of the rolling film 24 and the film of the rear side 26, protrude through the cuts 27 in said films and, because of their height, protrude above the upper side of the rear side film 26. After the photovoltaic module 30 has also been laminated, the regions folded 19 of the transverse contact wires 17 still protrude and can be electrically connected easily, as explained at the beginning.

For this purpose, it is also not important if, in the finished photovoltaic module, a single set of connections with folded regions 19, or two or three, for example, is provided. This depends on the design and electrical power of the photovoltaic module.

Claims

1. Method for producing or electrically connecting a photovoltaic module having a large variety of solar cells, at least two of them in each case are interconnected in a series circuit, where the series circuit has two connections and where the connections of one A large variety of series circuits are assembled for a connection device, characterized in that in each case several connections of identical polarity are connected to each other by means of transverse contact cables, which are guided along the solar cells above of a carrier glass from the front side down of a back side film, wherein the back side film extends above the solar cells and the transverse contact wires, wherein the transverse contact wires are folded together or folded upwards to a larger thickness extending away from the carrier glass on the front side, where the The transverse contact cables are guided through cuts in the rear side film and protrude above the rear side film for the subsequent electrical connection.

2. Method according to claim 1, characterized in that a transverse contact wire is folded up at least once, preferably twice, in which in particular a multiple folding up with folding by rolling is performed.

3. Method according to claim 1 or 2, characterized in that the transverse contact cables are guided near the leading edges of the front solar cells and in particular parallel one to the other, preferably with a distance of only a few mm to each other.

4. Method according to one of the preceding claims, characterized in that the cuts are produced in the film of the rear side before being placed on the solar cells, preferably by die-cutting.

5. Method according to claim 4, characterized in that the cuts have a rectangular shape.

6. Method according to one of the preceding claims, characterized in that the transverse contact cables folded upwards are also guided through cuts in an adhesive film or laminator placed between the solar cells and the film of the rear side, where preferably the cuts in the adhesive film or laminator correspond to the cuts in the film of the back side when it is placed one on top of the other.

7. Method according to one of the preceding claims, characterized in that the rear side film together with the adhesive film or laminator according to Claim 6 remains under the transverse contact cables bent or folded upwards so that the cables of transverse contact protrude a little above the upper side of the rear side film, preferably with a projection of at least 0.1 mm to 0.2 mm.

8. Method according to one of the preceding claims, characterized in that, after the placement of the film of the rear side, a rolling step is carried out and then the electrical connection is made with connecting units being connected, in particular bar welding, to the transverse contact cables, in particular connections of different polarity in a common junction box.

9. Method according to claim 8, characterized in that, first, a connection is made to the connection units and then a connection box is fixed to the photovoltaic module, in particular joined with adhesive.

10. Method according to one of the preceding claims, characterized in that a large variety of electrical connections are provided in the vicinity of each other, in particular two connections by the same connection pole with a transverse contact cable, wherein preferably the connections of different polarities are arranged compensated with respect to each other.

11. Photovoltaic module, in particular produced by a method according to one of the preceding claims, having several solar cells, at least two of them in each case are interconnected in a series circuit, where the series circuit has two connections and wherein the connections of a large variety of series circuits are assembled for a connection device, characterized in that in each case several connections of identical polarity are connected to each other by means of transverse contact cables which are guided along the solar cells above a carrier glass from the front side down a film of the rear side, where the film of the rear side extends above the solar cells and the cables of transverse contact, wherein the transverse contact wires are bent together or folded upwards to form a larger thickness extending away from the carrier glass on the front side and are guided through cuts in the back side film and protrude above the Back side film for electrical connection.

12. Photovoltaic module according to Claim 11, characterized in that a transverse contact wire is a tinned wire, preferably made of cr.

13. Photovoltaic module according to Claim 1 1 or 12, characterized in that a transverse contact wire is a flat wire having a width of at least 3 mm, in particular around 5 mm, where it preferably has a thickness of 0.3 mm to 0.4 mm.