EP2304805A2

EP2304805A2 - Method for producing a contact for solar cells

Info

Publication number: EP2304805A2
Application number: EP09737609A
Authority: EP
Inventors: Rudolf Güdel; Hans-Ulrich Kurt; Walter Zulauf; Rudolf Heid; Roland Kappaun; Marcel Blanchet
Original assignee: 3S Swiss Solar Systems AG; Guedel Group AG
Current assignee: 3S Swiss Solar Systems AG; Guedel Group AG
Priority date: 2008-04-30
Filing date: 2009-04-21
Publication date: 2011-04-06
Also published as: JP2011519170A; WO2009132468A3; JP5314751B2; CN102084490B; CN102084490A; KR20110044943A; EP2113945A1; WO2009132468A2; US8603838B2; US20110111534A1

Abstract

The invention relates to a method for producing a contact for solar cells (30) arranged in a laminated solar panel (1), wherein the solar cells (30) are coated on both sides of the main surfaces thereof with at least one layer and before a lamination step the solar cells (30) are connected with electrically-conducting connectors (31, 33), the electrically conducting connectors (31, 33) being arranged in the solar panel for laminating such as to be completely laminated within the solar panel (1) after the lamination step. After the lamination step a contact region (35) of the electrically-conducting connector (33) is exposed, wherein at least one of the layers covering the solar cells is completely punched through in the corresponding region, in particular by stripping. The contact region (35) of the electrically-conducting connector (33) can then be contacted by means of an externally-accessible contact element. The incorporation of the connector (31, 33) can be automated as the electrical connector (31, 33) can be laid essentially flat in the corresponding plane of the layer system and no complex through holes are made before lamination. The position of the electrical connector (31, 33) within the layer system is possible to be more accurately deigned than the position of connectors extending from the layer system which significantly simplifies contacting the contact region (35) of the connector (31, 33), in particular with an automated solution.

Description

Process for producing a contact of solar cells

Technical area

The invention relates to a method for producing a contacting of solar cells arranged in a laminated solar panel, wherein the solar cells are covered on both sides of their main surfaces by at least one layer each. The invention further relates to a method for the production of solar panels, a solar panel and a system for the production of laminated solar panels. State of the art

It is known to construct solar panels (also called solar modules) in that a plurality of mechanically sensitive solar cells (photovoltaic cells, eg silicon-based thick-film solar cells) are electrically connected to one another and enclosed in a layer system. The layer system provides mechanical stability and protects the enclosed cells from the effects of the weather or mechanical damage. The layer system may, for example, be based on a glass substrate transparent to the relevant portions of the solar radiation and a backsheet between which the solar cells and the electrical connectors connecting them are enclosed. Films of EVA (ethylene vinyl acetate) or other suitable material are incorporated between said layers so that the layer system can be laminated together under the influence of heat and pressure. The solar cells can be enclosed by a frame.

A solar panel comprises electrical connections with which the solar cells which are electrically interconnected within the layer system can be contacted externally. As a rule, several (or all) of the solar cells included in a module are in

Series connected to allow sufficient output voltages. In addition, a solar module often includes several circles that can be tapped off individually, so that electricity can still be obtained even if the module is partially shaded. Instead of two connections (one per polarity), there are three, four or even more connections.

In known solar panel fabrication processes, to create the electrical connections prior to lamination of the layer system, some of the electrical connectors have been passed through the backsheet to the outside. After lamination, connecting elements such as sockets or plugs could then be connected to these connection lugs guided to the outside, e.g. B. by soldering.

The steps of making the feedthrough for the connectors and attaching the terminals are practically only manually possible. The outward led Connectors do not have a clear position and make handling of the solar panel difficult. In automation, correspondingly considerable difficulties, and the previous process is error-prone. Therefore, the entire manufacturing process for the solar panels is expensive and complicated.

Presentation of the invention

The object of the invention is to provide a method for producing a contacting of solar cells which belongs to the technical field mentioned at the outset and which can be automated (as far as possible) and has a lower susceptibility to errors.

The solution of the problem is defined by the features of claim 1. According to the invention, the following steps are carried out in the context of the method: Before a lamination step in the manufacture of the solar panel, the solar cells are connected by electrically conductive connectors, wherein the electrically conductive connectors are introduced into the solar panel to be laminated such that they are after the lamination step completely laminated in the solar panel. After the lamination step, a contact region of the electrically conductive connectors is exposed by at least one of the solar cells covering layers in a corresponding area completely pierced, in particular removed, is. Subsequently, the contact region of the electrically conductive connector is contacted by means of a tappable from the outside connecting element.

The contact area of the connector is therefore laminated first and is completely enclosed by the surrounding layers after lamination. After lamination, the contact area is then exposed again. Depending on the number of circles, there are two or more contact areas per solar panel.

By eliminating the need for elaborate feedthroughs prior to lamination and allowing the electrical connectors to be laid substantially flat into the appropriate plane of the layer system, the laying of the connectors can be automated. The geometry of the connectors can also be simplified. As for the subsequent process steps, in particular for laminating, no passages through individual layers of the layer system are present and since no connectors protrude from the layer system, the layer system can be handled in these subsequent process steps easier. In addition, the position of the electrical connectors within the layer system can be specified more precisely than the position of connector ends projecting from the layer system, which considerably simplifies the contacting of the contact region of the connectors, in particular in the case of an automated solution.

A solar panel produced by the method according to the invention thus comprises at least two layers which enclose a plurality of solar cells on both sides of their main surfaces and is constructed as follows: a) the layers and the solar cells are laminated together; b) the solar cells are interconnected by electrically conductive connectors located entirely within the layers; c) the electrically conductive connectors comprise a contact region located within the layers; d) an access to the contact area is present, which traverses at least one layer covering the contact area; and e) a tappable from the outside connecting element is guided through the access and electrically connected in the contact region of the connector with this, in particular welded or soldered.

Such a panel may be produced by a method comprising the steps of: a) providing a base substrate, in particular a glass plate; b) applying a first laminating film to the base substrate, in particular a film of EVA; c) connecting a plurality of solar cells by means of electrically conductive connectors; d) applying the solar cells to the first laminating film; e) applying a second laminating film to the solar cells, in particular a film of EVA; f) applying a backing layer to the second laminating film to produce the still unlaminated solar panel; g) laminating the unlaminated solar panels; h) exposing a contact region of the electrically conductive connector by completely piercing, in particular abrading, the backside layer and the bonding layer resulting from the second laminating film in a corresponding region; and i) contacting the contact region of the electrically conductive connectors by means of an externally tapped connection element.

In this case, the base substrate preferably forms the lowest layer during processing, but it is also conceivable within the scope of the invention to work in reverse, ie. H. Provide the base substrate as the top layer, or turn the partially built layer system during processing once or several times. The order of electrically connecting the solar cells (step c) and applying the solar cells to the first laminating film (step d) may be selected as desired.

A suitable plant comprises a) a station for connecting solar cells by electrically conductive connectors; b) a station for building the solar panel to be laminated, wherein the solar cells and the electrically conductive connectors are covered on both sides of their main surfaces by at least one layer; c) means for laminating the solar panel; d) a device, in particular a milling machine, for exposing a contact region of the laminated electrical connectors in the solar panel by at least one of the solar cells covering layers in a corresponding area completely pierced, in particular removed, is; and e) a device, in particular a soldering or welding station, for contacting the contact region of the electrically conductive connector by means of a tappable from the outside connecting element.

The mentioned stations and facilities work fully automatically with advantage. However, embodiments are also conceivable in which individual stations or devices are realized semi-automatically or manually.

The exposure of the contact area is thus advantageously by milling. Such a processing step is easy to automate, allows high precision and gentle processing of the affected layers of the laminated layer system and the electrical connector. The free milling also creates a clean surface for the subsequent connection process in the contact area of the connector. During milling, the processing point is advantageously cooled by air, and the resulting chips are sucked out. The cutter is advantageously designed so that the chips are as short as possible.

Other types of processing, eg. As cutting, punching or melting, are also conceivable in principle.

Advantageously, prior to exposing the contact region, a position of the electrically conductive connectors, in particular a layer and a depth, is measured. For this purpose, a device for measuring a position of the electrically conductive connector is preferably arranged in a corresponding system in the process before the device for exposing the contact region. The previous position measurement enables a precise exposure and a secure contact of the contact area. It is particularly desirable because with common laminates, the fully laminated connectors in the adjacent laminating film layer "float" and thus do not maintain their position accurately during the lamination process. The determination of the position allows a precise positioning of the machining tool to expose the contact area, the determination of the depth allows the setting of a precise machining depth and thus ensures that the contact area is actually exposed, but that at the same time there is no damage or excessive impairment of the electrically conductive connector.

The milling can be done by means of a commercially available computer-controlled milling head.

The detector for the position of the contact areas and the milling tool are advantageously mounted on the same head, resulting in a simple construction and a high

Achieve machining precision. First, the milling points to be machined are measured, then the milling takes place. If a plurality of contact areas are to be contacted with contact elements having a fixed relative allocation (layout), then the individual routing depths and a single position of the layout of the contact points are set on the basis of the measured values.

The measurement of the position of the electrically conductive connector is preferably carried out by means of an inductive sensor. Such a sensor is relatively inexpensive, it has also been shown that with such a both the lateral position of the laminated connector and the depth can be precisely determined in one operation, the results are not affected by the surrounding layers of the layer sequence disturbing. For example, a commercially available inductive sensor with analog current output is moved over the approximately expected position of the contact areas of the electrically conductive connectors. The lateral position of the connector can then be determined by detecting the minimum current, the depth by the absolute value of the minimum current.

There are also sensors conceivable based on a different principle, for. B. Ultrasonic or X-ray sensors or mechanical (tactile) sensors. Capacitive sensors seem less suitable because the measurement results are significantly influenced by the properties of the surrounding layers.

The electrically conductive connectors may be provided with a material reinforcement in their contact area prior to the lamination step, ie in the contact area the amount of material is increased. Even in a method of exposure in which the material of the connector is partially removed in order to ensure a reliable contact (for example, in a milling method), it is ensured that the remaining Cross-section of the connector is sufficient for the currents to be conducted. The material reinforcement can be achieved for example by a doubling of the connector (in particular if the connector is formed like a ribbon), ie a free end of the connector is folded over to double the material cross section; Subsequently, the folded portion is preferably connected to the underlying or overlying section, z. B. soldered. Instead of a doubling can also be another method of material accumulation, z. As upsetting, be applied or it is an additional element used.

The material reinforcement is advantageously already made before connecting the solar cells, d. H. those connectors that require reinforcement are already pre-assembled. As a result, the machining process can be kept simple.

Alternatively, the gain, z. B. the flipping to make a doubling, only after connecting the solar cells.

For example, instead of reinforcing the material, the cross section of the electrical connector may be continuously enlarged or a method of exposure may be used in which the cross section is not reduced.

The electrically conductive connectors are advantageously arranged such that all contact areas come to rest in an edge region of the solar panel and, in particular, adjacent to one another. As a result, a simpler layout of the connectors is made possible, and in addition, in the region of the connection, additional insulation from underlying solar cells can be dispensed with. There is also no risk that solar cells could be damaged by the exposure of the contact areas due to mechanical and / or thermal influences.

Alternatively, the connection takes place in the area of the solar cells. This requires additional insulation and a method of exposure, in which there is no risk of damage to solar cells. For this, the ratio of the cell area to the total area can be increased, which results in a higher area efficiency.

The peripherally located electrically conductive connector can be arranged in the region of the contact areas on an additional common carrier, ie on a carrier that is not part of the layer sequence and which is present only in the region of the contact areas. Suitable as a support, for example, a band of polyvinyl fluoride (Tedlar). The carrier and optionally the connectors to be arranged in the region of the carrier together with the contact regions can be prefabricated, which simplifies the processing. By the carrier also a separation of the underlying connector from the front of the solar panel is created, whereby the connector of any harmful influences, such. As against solar radiation, are protected and whereby the aesthetics of the solar panel is improved. The carrier also provides a thermal barrier against the preceding layer and thus prevents damage to the same when the connection element z. B. is connected by welding or soldering to the contact region of the electrically conductive connector.

Alternatively, the connectors are only placed on the surrounding layers.

The solar cells are preferably connected to each other by means of longitudinal connectors to strands, and various of the strands are electrically connected by means of cross-connector, wherein the contact areas are formed on the cross connectors. This achieves a simple layout. A particularly simple layout results when both the longitudinal and the transverse connectors are straight and are arranged at right angles to each other. Due to the currents to be conducted, the transverse connectors have a larger cross-section than the longitudinal connectors. Safe and durable contact areas can therefore be made simpler at the cross connectors than at the comparatively thin longitudinal connectors. In particular, the cross connector can be arranged in the edge region of the solar panel and optionally on an additional carrier.

Alternatively, other layouts can be used.

The connection of the plurality of solar cells by means of electrically conductive connectors is advantageously carried out before the application of the solar cells to the first laminating film. This ensures that bonding (in particular by soldering) does not impair the laminating film. Already before placing the produced strands and / or the entire layouts are also electrically checked, z. B. by a so-called dark current test.

The connection of the longitudinal connectors to the cross connector or the cross connectors and / or the contacting of the contact region of the electrically conductive connector by the tappable from the outside connecting element is preferably carried out by a flux-free connection. Conventional fluxes evaporate and react with the material of the laminating films (eg EVA), which limits the operating temperature for the polymerization process upwards. Corresponding to the lower operating temperature, longer lamination times are required. If you can do without flux, z. Example, by a method of wire bonding (wire bonding) is used and accordingly the reaction with the lamination material is omitted, the efficiency of the process can be significantly increased due to significantly lower lamination times.

The externally tappable connecting element is advantageously arranged in a junction box, wherein the junction box for contacting the contact region of the electrically conductive connector is applied with a first main surface on a back of the laminated solar panel. The junction box protects the contact points with the electrical connectors and provides a stable and permanent connectivity.

In the context of a preferred embodiment, the connection element is fastened (mechanically) to the connection box with a first end and has a resilient design with its second, free end, so that the resilient end makes contact with the contact area after application of the connection box. Subsequently, the resilient end connected to the contact area, in particular welded or soldered, are. The resilient configuration of the connection elements ensures a tolerance compensation between the connection elements and the corresponding contact areas.

The connection element is preferably arranged in the region of an opening which runs through from the first main surface to the rear side of the connection box, so that a connection tool is connected to one of the connection elements for connecting the connection element to the contact region Rear can be brought to the connection element. Because the contact area remains accessible directly from behind even after the connection box has been set up, automation of the connection step is greatly simplified. After placing the can and connecting the free end, the opening is preferably potted with the contact area. The encapsulation achieves immobilization of the interconnected elements and long-term protection of the contact points.

The electrically conductive connectors are advantageously band-like at least in the contact region, wherein they are introduced substantially flat between the layers of the solar panel, d. H. the major surfaces of the band-like connectors are parallel with the major surfaces of the individual layers of the layer sequence. With ribbon-like connectors, it is possible to achieve sufficient cross-sections for the currents to be conducted, while at the same time avoiding over-application of the connectors and, for example, impairing the uniform lamination of the layer system.

From the following detailed description and the totality of the claims, further advantageous embodiments and feature combinations of the invention result.

Brief description of the drawings

The drawings used to explain the embodiment show:

Figure 1 is a schematic representation of a plan view of a solar panel according to the invention.

Figure 2 is a schematic representation of a cross section through the solar panel.

Fig. 3 is a schematic cross-sectional view of the determination of the position of a

Contact area;

4 shows a schematic cross-sectional representation of the exposure of a contact region; Fig. 5 is a schematic cross-sectional view of an exposed

Contact area;

Fig. 6 is a schematic cross-sectional view of the contacting of

Contact area;

Fig. 7 is a schematic plan view of the back of the solar panel and the

Junction box; and

Fig. 8 is a block diagram of an inventive system for the production of

Solar panels.

Basically, the same parts are provided with the same reference numerals in the figures.

Ways to carry out the invention

1 shows a schematic representation of a plan view of a solar panel according to the invention. FIG. 2 is a schematic representation of a cross section through the solar panel. The solar panel 1 comprises as the base substrate a glass plate 10 made of toughened safety glass. On this, a layer system of a first transparent plastic layer 20 of ethylene vinyl acetate (EVA), a plurality of known solar cells 30, a second plastic layer 40 of ethylene vinyl acetate (EVA) and a backsheet 50 made of polyester constructed. The solar panel 1 is arranged (eg, fixed on a building roof) in such a way that the glass plate 10 faces the sun. The solar radiation passes through the glass plate 10 and the first transparent plastic layer 20 and strikes the embedded between the plastic layers 20, 40 solar cells 30, where an electrical voltage is generated.

Each of the solar cells 30 (six in the example shown) are connected in series by longitudinal connectors 31 to a plurality of (in the illustrated example six) strands 32.1... 32.6. The corresponding compounds are shown in Figure 1 in part only hinted (dashed lines). The longitudinal connectors 31 are soldered to contact surfaces of the solar cells 30. Each two of the strands 32.1, 32.2 or 32.3, 32.4 or 32.5, 32.6 are in turn connected in series, wherein the connection is provided by cross connector 33. The circuit shown in Figure 1 has four taps (see below), wherein the two first interconnected strands 32.1, 32.2 between a first and a second tap, the third and fourth interconnected strand 32.3, 32.4 between the second and a third tap and the fifth and sixth interconnected strand 32.5, 32.6 are connected between the third and a fourth tap. It is thus possible to pick up all solar cells 30 or individual areas of the solar panel 1 in a targeted manner.

The cross connectors 33 mentioned are tinned 5x0.4 mm copper strips. The tin layer has a thickness of about 20 microns. The cross section is chosen so that the expected maximum currents can be conducted. The transverse connectors 33 are arranged in two opposite edge regions of the solar panel 1 and extend substantially perpendicular to the longitudinal connectors 30, the main surfaces of the transverse connectors 33 lying parallel to the main surfaces of the individual layers of the layer system. The cross connectors 33 are applied by means of a layer of EVA on a carrier tape 34 made of polyvinyl fluoride (Tedlar). In one of the mutually opposite edge regions of the solar panel, each of the four transverse connectors 33 arranged in one half of the solar panel 1 comprises a contact region 35 in the region of a free end, wherein the contact regions 35 provide the abovementioned taps and wherein they are arranged adjacent to each other in such a way that the four contact regions 35 form a trapezoidal contact quadrilateral 36. The solar cells 30, the longitudinal connectors 31 and the carrier tapes 34 with the cross connectors 33 are all enclosed between the two plastic layers 20, 40. At the contact areas 35, d. H. at the respective free ends, the cross connectors 33 are folded to 12 mm in length and the folded end is soldered, so that the cross section of the cross connector 33 is doubled in the contact areas.

On the back of the solar panel 1, a junction box 60 is set, which

Having connecting elements which can be connected to the contact areas 35 of the cross connector 33 (see below, Fig. 6 and 7). In the junction box 60 freewheeling diodes are arranged, which prevent in a conventional manner that the Output voltage collapses when z. B. the solar panel is partially shaded by shaded areas as it were "hidden". The solar panel 1 can also with a frame, z. B. aluminum, are provided (not shown).

In the following we describe the production of the solar panel 1. A suitable system is shown in Figure 8 in a block diagram. For the manufacture of the solar panel 1, the glass plate 10 is first cleaned and prepared for the further process steps (station 120). In a further station 1 10, the solar cells 30 are first connected to the longitudinal connectors 31 to strings 32.1 ... 32.6, then the strands are interconnected by means of the cross connector 33. Subsequently, in a further station 130, the layer system is placed stepwise on the glass plate 10, ie a first plastic film of EVA to form the first plastic layer 20, the interconnected solar cells 30 together with longitudinal and transverse connectors 31, 33, a second plastic film to form the second plastic layer 40 and the backsheet 50 are placed on the glass plate. Next, in a lamination device 140, the lamination of the module takes place under reduced pressure and approximately 150 ^° C. During lamination, clear, three-dimensionally crosslinked and non-fusible plastic layers 20, 40 in which the solar cells 30 are formed form the hitherto milky EVA plastic films and the connectors are now embedded and firmly connected to each other and to the glass plate 10 and the backsheet 50. After lamination, the edges are lined, the junction box 60 is set and equipped with the freewheeling diodes. Now the solar panel 1 is still framed, measured and classified and packed according to its electrical values.

With reference to FIGS. 3 to 6, the contacting according to the invention of the contact regions of the transverse connectors will be described. FIG. 3 is a schematic cross-sectional illustration of the determination of the position of a contact region 35 in a corresponding measuring device 150. For this purpose, an inductive sensor 70, for example, is used. B. an analog sensor type IWRM 12 from Baumer Electric, Frauenfeld, Switzerland with a measuring distance of 0 - 4 mm, passed over the back of the already laminated solar panel 1 and measured the output current at various positions. In addition to the analog sensor mentioned, the measuring system consists of a current source (24 V DC), a suitably selected load resistor and a multimeter, which is installed in the resulting output current range (here 4 ... 2O mA) has sufficient resolution. It has been found that removal of the sensor from the back sheet of 1.6 mm gives good results. In order to ensure a clear relationship between the position measurement and the subsequent milling process described below, the sensor is attached to the milling spindle support via a dial gauge holder, whereby the sensor is set back by 1.0 mm relative to the milling tip. In the described embodiment, there is only the need to determine the lateral position of the cross connector 33, as a longitudinal displacement, along the extension of the cross connector 33, is not critical.

If the sensor 70 is guided transversely to the cross connector 33, the position at which a minimum output current is measured corresponds to the center of the cross connector 33. From the absolute value of the minimum output current, it is also possible to deduce the depth of the cross connector 33. So that the depth can always be determined reliably, the sensor 70 is calibrated regularly. For this purpose, control measurements on processed solar panels 1 and / or measurements on predetermined patterns can be used. The measurement is repeated for all four contact areas 35 so that four transverse positions and four depths are determined. After determining the four lateral positions, an average value is determined, which later makes it possible to position the contact quadrangle so that all transverse connectors 33 can be reliably contacted. The measured values are stored for the next process step.

FIG. 4 shows a schematic cross-sectional representation of the exposure of a contact region. For this purpose, a milling tool 80 fastened to a milling spindle support 160 known per se is guided at the predetermined position through the backsheet 50 and the rear plastic layer 40 to the cross connector 33, wherein the mentioned layers and the tin layer of the cross connector 33 in this area be removed. By doubling the cross connector 33 in its end region ensures that even after the complete removal of the tin layer, a sufficient cross section for the conduction of the expected currents is available. In the illustrated embodiment, the milling tool 80 is a HSS two-cutter, which is operated at high speed. The milling tool 80 is designed such that the shortest possible chips are formed. During the milling process, the processing point is cooled with air. The depth of cut is - depending on the measured depth of the contact point - chosen such that the tin layer of the cross connector 33 is reliably removed, but that the remaining cross section of the doubled in this section cross connector 33 is still sufficient to carry the expected maximum current. The four milling sites have a fixed geometric association with each other, the contact quadrangle is positioned relative to the solar panel 1 according to the measurements made in the previous step.

FIG. 5 is a schematic cross-sectional illustration of the now exposed contact region 35. FIG. 6 shows a schematic cross-sectional representation of the contacting of the contact region 35 in a corresponding station 170. FIG. 7 shows a schematic plan view of the back side of the solar panel and the junction box. After exposing the contact areas 35, 35.1 ... 35.4, resilient connection lugs 90, 90.1 ... 90.4 are guided with their free, bent into the horizontal end to the contact areas 35, 35.1 ... 35.4. The free end can then be soldered to the contact area 35, 35.1 ... 35.4. The free ends of the terminal lugs 90, 90.1 ... 90.4 are positioned in a front-to-front opening 61 of the junction box 60 so that the soldering tool can access the terminal lugs 90, 90.1 ... 90.4 from behind through this opening 61 , After soldering all four connection lugs 90, 90.1 ... 90.4, the opening 61 can be potted with a suitable casting agent.

The invention is not limited to the illustrated embodiment. For example, the layout of the solar cells, the connectors and the pads can be chosen differently. The materials mentioned are only exemplary embodiments, for. B., instead of the layers of EVA, other materials can be used, for. B. silicone rubber. The Rückseitenkaschierung can also be made of a different material, eg. B. made of polyvinyl fluoride (Tedlar). Also, the base substrate does not have to be a glass plate, but z. B. made of a plastic material. The invention is applicable in the context of most commercially available solar cells, in particular both mono- and polycrystalline cells. Instead of a doubling of the free ends of the transverse connectors, transverse connectors with a somewhat enlarged cross section can be used, so that even after the exposure of the contact area, a sufficient cross section for the conduction of the maximum expected currents is present. Instead of a solder connection between the terminal lugs and the contact areas of the cross connector, a welded connection can also be created or a method known per se for wire bonding can be used.

Also, the junction box can be designed differently, for example, the contact elements can be formed by means of coil springs mounted contact pieces or the (initial) contact is not made by springs, but only during the connection process by the external tool.

In summary, it should be noted that a method for producing a contact of solar cells is provided by the invention, which is automated and has a lower susceptibility to errors.

Claims

claims

1. A method for producing a contacting of in a laminated solar panel (1) arranged solar cells (30), wherein the solar cells (30) on both sides of their main surfaces of at least one layer (10, 20, 40, 50) are covered, comprising the following steps a) prior to a lamination step, bonding the solar cells (30) through electrically conductive connectors (31, 33); b) wherein the electrically conductive connector (31, 33) are introduced into the solar panel to be laminated so that they are completely laminated in the solar panel (1) after the lamination step; c) after the lamination step exposing a contact region (35) of the electrically conductive connector (33) by at least one of the solar cells covering layers (40, 50) in a corresponding area completely pierced, in particular removed, is; and d) contacting the contact region (35) of the electrically conductive connectors (33) by means of an externally tapped connection element (90).

2. The method according to claim 1, characterized in that before the exposure of the contact region (35), a position of the electrically conductive connector (33), in particular a position and a depth, is measured.

3. The method according to claim 2, characterized in that the measurement by means of an inductive sensor (70) is made.

4. The method according to any one of claims 1 to 3, characterized in that the exposure of the contact area (35) by milling takes place.

5. The method according to any one of claims 1 to 4, characterized in that the electrically conductive connector (31, 33) are arranged such that all contact areas (35) in an edge region of the solar panel (1) and in particular come to lie adjacent to each other.

6. The method according to claim 5, characterized in that the electrically conductive connector (33) in the region of the contact regions (35) on an additional common carrier (34) are arranged.

7. The method according to any one of claims 1 to 6, characterized in that the solar cells (30) by means of longitudinal connectors (31) are interconnected to strands (32) and that various of the strands (32) by means of cross-connector (33) are electrically connected, wherein the contact regions (35) are formed on the cross connectors (33).

8. The method according to claim 7, characterized in that the connecting of the longitudinal connector (31) with the cross connector (33) and / or contacting the contact region (35) of the electrically conductive connector (33) by the tappable from the outside connecting element (90) done by a flux-free connection.

9. The method according to any one of claims 1 to 8, characterized in that the externally tappable connection element (90) in a junction box (60) is arranged, wherein the junction box (60) for contacting the contact region (35) of the electrically conductive connector (60). 33) having a first major surface is applied to a back side of the laminated solar panel (1).

10. The method according to claim 9, characterized in that the connecting element (90) is fastened with a first end to the junction box (60) and that the connecting element (90) is designed resiliently with its second, free end, so that the resilient end after applying the junction box (60) the Contact area (35) contacted, wherein then the resilient end connected to the contact area (35), in particular welded or soldered, is.

1 1. A method according to claim 10, characterized in that the connection element (90) in the region of a through opening (61) of the junction box (60) is arranged, so that for connecting the connection element (90) with the contact region (35), a connecting tool from a rear side can be brought to the connection element (90), wherein preferably the opening (61) after placing the junction box (60) and connecting the free end with the contact region (35) is cast.

12. The method according to any one of claims 1 to 1 1, characterized in that the electrically conductive connector (33) at least in the contact region (35) are band-like, being substantially flat between the layers (20, 40) of the solar panel (1). be introduced.

13. A method for producing solar panels (1), comprising the following steps: a) providing a base substrate (10), in particular a glass plate; b) applying a first laminating film (20) to the base substrate (10), in particular a film of EVA; c) connecting a plurality of solar cells (30) by means of electrically conductive connectors (31, 33); d) applying the solar cells (30) to the first laminating film (20); e) applying a second laminating film (40) to the solar cells (30), in particular a film of EVA; f) applying a backing layer (50) to the second laminating film (40) to produce the still unlaminated solar panel; g) laminating the unlaminated solar panels; h) exposing a contact region (35) of the electrically conductive connectors (33) by completely piercing, in particular abrading, the backside layer (50) and the bonding layer resulting from the second laminating film (40) in a corresponding region; i) contacting the contact region (35) of the electrically conductive connectors (33) by means of a connection element (90) which can be tapped off from the outside.

14. The method according to claim 13, characterized in that the connecting of the plurality of solar cells (30) by means of electrically conductive connectors (31, 33) prior to the application of the solar cells (30) on the first laminating film (20).

A solar panel (1) comprising at least two layers (10, 20, 40, 50) enclosing a plurality of solar cells (30) on both sides of their major surfaces, wherein a) the layers (10, 20, 40, 50) and the Solar cells (30) are laminated together; b) the solar cells (30) are interconnected by electrically conductive connectors (31, 33) located entirely within the layers; c) the electrically conductive connectors (31, 33) comprise a contact region (35) located within the layers; d) an access to the contact region (35) is present, which traverses at least one layer (40, 50) covering the contact region (35); e) a tappable from the outside connecting element (90) guided through the access and in the contact region (35) of the connector (33) electrically connected thereto, in particular welded or soldered, is.

16. Plant for the production of laminated solar panels (1), comprising

a) a station (1 10) for connecting solar cells (30) by electrically conductive connectors (31, 33); b) a station (130) for constructing a solar panel (1) to be laminated, wherein the solar cells (30) and the electrically conductive connectors (31, 33) are provided on both sides of their main surfaces by at least one layer (10, 20, 40, 50) are covered;

c) means (140) for laminating the solar panel (1);

d) a device (160), in particular a milling machine, for exposing a contact region (35) of the electrical connector (31, 33) laminated in the solar panel (1) by at least one of the solar cells covering layers (40, 50) in a corresponding Area completely pierced, in particular removed, is; and

e) a device (170), in particular a soldering or welding station, for contacting the contact region (35) of the electrically conductive connectors (31, 33) by means of a connection element (90) which can be tapped from the outside.

17. Plant according to claim 16, characterized by a in the process before the device for exposing the contact region (35) arranged means (150, 70) for

Measuring a position of the electrically conductive connectors (33).