Solar cell module and method for manufacturing the solar cell module

Abstract

The present invention relates to a solar cell module having a plurality of photovoltaic solar cells with electrically contactable back surfaces, the solar cells being arranged in a matrix-shingle configuration with a plurality of spatially parallel solar cell rows, each row containing a plurality of solar cells, the solar cell rows being arranged to overlap in an overlapping region such that the back surfaces of solar cells in one solar cell row partially cover the front surfaces of solar cells in an adjacent solar cell row, and the solar cells are arranged such that the back surface of at least one solar cell in one solar cell row partially covers the front surfaces of at least two solar cells in an adjacent solar cell row. The present invention is characterized in that at least one solar cell row has conductive cross connectors that cover and electrically contact at least 50% of the back surfaces of at least the non-edge solar cells in the solar cell row.

Description

[Technical Field]

[0001] The present invention relates to a solar cell module according to claims 1 and 16 to 18 and to a method for manufacturing a solar cell module according to claim 12. [Background technology]

[0002] Photovoltaic solar cells generally have a metal contact structure on the front surface, which is not transparent to the incident electromagnetic radiation and therefore reduces the available absorption surface area on the front surface.

[0003] It is therefore known to form a solar cell module with a single structure, in which adjacent solar cells overlap, so that the back surface of one solar cell covers the front surface of the adjacent solar cell in the overlapping region. This allows a metal contact structure to be located on the front surface of the solar cell in the overlapping region, and thus underneath the adjacent solar cell, so that the solar cell located above in the overlapping region does not need to have an extensive metal contact structure on its front surface. This allows for a larger proportion of the solar cell area available for light absorption relative to the solar cell module area.

[0004] A particularly advantageous configuration of solar cells is achieved in a matrix-single configuration, where several solar cell rows, each with several solar cells, are arranged in parallel spatially such that one solar cell covers the front of at least two adjacent solar cells in the overlapping areas. Thus, in the matrix-single configuration, the solar cells are arranged offset in the lateral direction relative to the solar cell rows.

[0005] In the overlap region, the solar cell strings are electrically connected to form an electrical series connection of the solar cell strings.

[0006] Essentially, a solar module requires connection elements to electrically connect the solar module to external electrical elements and / or other solar modules.

[0007] In addition, in the case of partial shading, bypass diodes must be provided for typical solar cell module sizes in order to avoid local overheating (hot spots) and the resulting damage to the solar cell module. Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention is therefore based on the object of providing a method for manufacturing a solar cell module and a solar cell module having solar cells in a matrix shingle configuration, which allows a robust and inexpensive interconnection with external circuits and / or internal electrical elements, in particular bypass diodes. [Means for solving the problem]

[0009] This problem is solved by a solar cell module according to claims 1 and 16 to 18 and by a method for manufacturing a solar cell module according to claim 12. Advantageous embodiments can be found in the dependent claims.

[0010] The solar cell module according to the invention is preferably produced by the method according to the invention, in particular by a preferred embodiment of said method. The method according to the invention is preferably designed for producing the solar cell module according to the invention, in particular by a preferred embodiment of said solar cell module.

[0011] The cell module according to the present invention comprises a plurality of photovoltaic solar cells having electrically contactable back surfaces. The solar cells are arranged in a matrix-shingle configuration with a plurality of spatially parallel solar cell rows, each row containing a plurality of solar cells, and the solar cells are arranged to overlap in an overlap region such that the back surface of a solar cell in one solar cell row partially covers the front surface of a solar cell in an adjacent solar cell row, and the solar cells are arranged such that the back surface of at least one solar cell in one solar cell row partially covers the front surfaces of at least two solar cells in the adjacent solar cell row. Preferably, the overlapping solar cells are electrically connected in the overlap region. Preferably, the electrically connected solar cell rows are electrically connected in series by the electrically connected overlap region.

[0012] Therefore, this configuration corresponds to the matrix single configuration mentioned at the beginning.

[0013] Preferably, at least each non-edge solar cell in one, and in particular each non-edge solar cell row, partially covers with its back surface the front surfaces of at least two solar cells of the adjacent solar cell row, and depending on the form of the matrix configuration, the edge solar cells of some solar cell rows have a narrower width, which makes it possible for the edge solar cell to cover only one solar cell of the adjacent solar cell row rather than two.

[0014] What is important is that at least one solar cell string has an electrically conductive cross-connector that covers and electrically contacts at least 50% of the rear surface of at least the non-edge solar cells of the solar cell string.

[0015] The problem stated at the outset is therefore solved by a method for producing a solar module, which comprises the following method steps: The solar cells are arranged in a matrix-shingle configuration to form a plurality of spatially parallel solar cell rows, each row having a plurality of solar cells. The solar cell rows are arranged to overlap at an overlap region, such that the back surface of a solar cell in one solar cell row partially covers the front surface of a solar cell in an adjacent solar cell row, and the solar cells are arranged such that at least one back surface of a solar cell in one solar cell covers the front surface of at least two solar cells in the adjacent solar cell row. It is preferable that a conductive connection is formed between the overlapping solar cells in the overlap region.

[0016] What is important is that in at least one solar cell row, conductive cross-connectors are arranged that cover and electrically contact at least 50% of the rear surface of at least the non-edge solar cells of the solar cell row.

[0017] Therefore, according to the present invention, a cross connector is provided that covers a wide area of ​​at least the rear surface of one solar cell row and electrically connects the solar cells.

[0018] This creates a wide range of possibilities for attaching connection elements to solar cells arranged in a matrix shingle configuration.

[0019] The cross connector provides a mechanically stable connection and therefore a robust structure due to its wide-area configuration and extensive contact with the backside of the solar cells, and furthermore, the large area that the cross connector covers on the backside of the solar cells in the solar cell string allows for a low absolute electrical contact resistance between the cross connector and the backside of the solar cells. Thus, this inexpensive and robust configuration allows for the attachment of terminals for external connections, junction boxes or electrical and electronic components of the solar cell module, in particular connection elements such as bypass diodes.

[0020] In order to improve the mechanical stability and reduce the electrical contact resistance between the solar cells and the cross connectors, it is advantageous for the cross connectors to cover and electrically contact at least 60%, preferably at least 70%, in particular at least 80% of the back surface of at least the non-edge solar cells in the solar cell string. Correspondingly, in the method according to the invention, it is advantageous for the cross connectors to be formed in such a way that they cover and electrically contact at least 60%, preferably at least 70%, in particular at least 80% of the back surface of at least the non-edge solar cells in the solar cell string.

[0021] The solar cells at both edges of the solar cell string where the conductive cross connectors are located may be covered by the conductive cross connectors at a lower coverage rate in order to reduce the requirements for process precision and / or to save material. Advantageously, the solar cells at both edges of the solar cell string are each covered by the conductive cross connectors by at least 20%, preferably at least 30%, and in particular at least 40%, and are electrically connected to the cross connectors. To reduce the contact resistance, it is advantageous for the solar cells at both edges of the solar cell string to be covered by the conductive cross connectors by at least 50%, in particular at least 60%, preferably at least 70%, and in particular at least 80%. It is particularly advantageous for the solar cells at both edges of the solar cell string to have the same coverage rate with the conductive cross connectors as the solar cells inside the solar cell string (i.e., not at the edges, but arranged between the solar cells at both edges).

[0022] The above-mentioned coverage percentages are relative to the area of ​​the back surface of each solar cell.

[0023] A particularly simple and inexpensive construction is achieved in a preferred embodiment in which the cross connectors are formed as conductive adhesive tapes, and accordingly, it is advantageous to use conductive adhesive tapes as cross connectors in the method according to the invention.

[0024] Such conductive adhesive tapes (conductive tapes or charge collecting tapes) are commercially available and have the additional advantage that they do not require heat treatment, which can damage the solar cell components, to form the mechanical and conductive connections.

[0025] In another advantageous embodiment, the cross connectors are mechanically and electrically conductively attached to the solar cells using a conductive adhesive. In particular, the cross connectors are preferably formed as metal foils. Accordingly, in the method according to the invention, the cross connectors are preferably attached to one solar cell string using a conductive adhesive, and metal foils are preferably used as the cross connectors.

[0026] The use of metal foils, especially flexible metal foils, has the advantage that commercially available metal foils are available which have very good electrical conductivity.

[0027] Similarly, electrically conductive adhesives (ECA) are also commercially available.

[0028] For typical conductive adhesives, heat treatment is necessary or at least advantageous to cure the conductive adhesive.

[0029] In the manufacture of solar modules, solar cells are typically placed between a carrier substrate and at least one flexible covering element, in particular an encapsulating foil, after which a material-integral thermal bonding by lamination is carried out to bond the carrier substrate and the foil together.

[0030] The use of a conductive adhesive to connect the cross connectors to the solar cell strings has the advantage that the conductive adhesive can be cured during lamination, eliminating the need for an additional heat treatment step. Therefore, in the method for manufacturing a solar cell module according to the invention, it is advantageous to perform the curing of the conductive adhesive during lamination of the solar cell module. In particular, it is preferable to arrange the solar cells between a carrier substrate and a flexible covering element, and to perform a material-integrated bond between the carrier substrate and the covering element during lamination, preferably between the cross connectors and the solar cells.

[0031] It is within the scope of the present invention to form the cross-connector as a metal foil, preferably made of one of the metals copper, tinned copper and aluminum.

[0032] The metal foil preferably has a thickness in the range of 5 μm to 100 μm, more preferably 10 μm to 50 μm, and particularly preferably 25 μm to 35 μm.

[0033] It is also within the scope of the present invention for the cross-connector to have multiple layers, in particular a flexible carrier layer coated with a conductive metal layer.

[0034] The total thickness of the adhesive tape and / or cross connector when formed as a multi-layer cross connector is preferably in the range of 5 μm to 100 μm, more preferably 10 μm to 50 μm.

[0035] Thus, by using the present invention, even when the solar cells are arranged in a matrix single configuration, it is possible in a simple manner to electrically contact the individual columns of the solar cell module separately or to couple them to other electrical or electronic components, such as bypass diodes.

[0036] For this purpose, it is preferred that the solar cell module has at least one electrically conductive longitudinal connector that is electrically connected to the cross-connector of one solar cell string, and that the longitudinal connector extends over another cross-connector of the solar cell module. It is within the scope of the present invention that the longitudinal connector extends over another cross-connector of the solar cell module.

[0037] The longitudinal connectors thus enable in a simple manner the interconnection of solar cell strings with cross-connectors, in particular the conductive connection of the solar cell strings to the junction boxes of the solar cell modules.

[0038] The longitudinal connector is preferably formed as a metallic, particularly preferably copper, longitudinal connector and preferably has a thickness in the range of 300 μm to 500 μm.

[0039] Advantageously, the vertical connectors are electrically insulated from the other solar cell rows of the solar module or from other cross-connectors by an electrical insulating layer. It is within the scope of the present invention that the vertical connectors are enclosed by an electrical insulating layer. It is also within the scope of the present invention that an electrical insulating layer is arranged only between the vertical connectors and the insulated elements, in particular other solar cells of the solar module and / or other cross-connectors.

[0040] In an alternative advantageous embodiment, the longitudinal connectors are electrically conductively connected to at least one electrical cross connector, which advantageously has a higher flexibility than the longitudinal connectors, and thus the longitudinal connectors are advantageously arranged between the solar cells and the cross connectors.

[0041] Advantageously, the vertical connectors are electrically conductively connected to the solar cells in the areas where the cross connectors cover the vertical connectors, so that an electrically conductive connection is also formed in the areas where the vertical connectors are arranged between the solar cells and the cross connectors, where an indirect electrically conductive connection is made between the cross connectors and the solar cells of the solar cell string via the vertical connectors.

[0042] It is known that photovoltaic modules have one or more junction boxes, in particular on the rear side of the photovoltaic module, which are used to protect the connection elements and / or the electrical and electronic components from external influences.

[0043] Advantageously, therefore, the solar module has one junction box in each of the at least two solar cell rows, the longitudinal connector extending between the junction boxes and electrically connecting, in particular, the electrical terminals of both junction boxes.

[0044] It is advantageous to place one or more bypass diodes in one or more junction boxes of the solar module.

[0045] As previously mentioned, cross connectors provide a simple method for electrically interconnecting bypass diodes in a matrix-shingle configuration.

[0046] In a preferred embodiment, the solar cell module therefore comprises at least one bypass diode, and the cross-connector is electrically conductively connected to the bypass diode of the solar cell module. In particular, it is advantageous if the solar cell module comprises at least two solar cell strings, each of which comprises one cross-connector, and the bypass diode is electrically conductively connected to both solar cell strings via the cross-connectors in the usual way, in particular connected in parallel to the solar cell strings in the usual way.

[0047] In order to visually uniformly form the front surface of the solar cell module, it is advantageous for the cross connectors, at least in the spaces between the solar cells on the side facing the solar cells of the solar cell string, and preferably over the entire surface, to have a color corresponding to the color of the front surface of the solar cells. Typical solar cells have a blue or black hue on their front surface. Therefore, it is preferred that the cross connectors, at least in the spaces between the solar cells on the side facing the solar cells of the solar cell string, and preferably over the entire surface, be formed in blue or black, preferably black.

[0048] Thus, in a preferred embodiment, the solar cell module has a plurality of cover strips arranged between the solar cells and the cross connectors in the region where the cross connectors extend across the space between two adjacent solar cells of a solar cell row, so that only the cover strips are visible on the front surface of the solar cell module, but not the cross connectors. The cover strips preferably have a color corresponding to the color of the front surface of the solar cells, particularly preferably blue or black.

[0049] The cover strip is preferably formed to be electrically insulating.

[0050] The present invention has the advantage that it is possible to develop a solar module of matrix shingle construction, which is known per se, by providing one or more additional cross-connectors. In particular, it is within the scope of the present invention to use known photovoltaic solar cells, in particular commonly used subcells, to form a solar module.

[0051] In an advantageous development of the solar cell module, solar cells with an improved metallic back contact structure are used in a string of solar cells which are electrically connected by means of at least a cross-connector: Advantageously, at least in the solar cell row in which the cross connector is arranged, the solar cells each have a metallic back contact structure which extends beyond the overlap region on the back surface of the solar cell so that a partial region of the series connection in the metallic back contact structure is in close contact with the front surface of the adjacent solar cell in the overlap region, and a partial region of the cross connect in the metallic back contact structure is covered by the cross connector and is directly conductively connected to the cross connector.

[0052] For single solar cells, it is known to form a metallic back contact structure in the form of a strip, like a busbar, on at least one side of the back surface, where the solar cells overlap so that the metallic back contact structure is in intimate contact with the metallic front contact structure of an adjacent solar cell to form an electrical series connection in the overlapping region.

[0053] In this development, the metallic back contact structure has a cross-connect sub-region in addition to the series connection sub-region overlapping with the adjacent solar cell, where the solar cell does not overlap with the adjacent solar cell in the cross-connect sub-region, so that the metallic back contact structure is accessible in the cross-connect sub-region and a cross-connector can be placed in the cross-connect sub-region of the metallic back contact structure and electrically connected to the cross-connect sub-region.

[0054] This has the advantage that it is possible to form conductive connections with very low contact resistance.

[0055] Preferably, the metallic back contact structure is at least 50% composed of a metal from the group consisting of silver and copper.

[0056] Generally known solar cells have an extensive, particularly full-surface, aluminum layer on the back surface, which is used for charge carrier coupling and dissipation. Although aluminum is inexpensive, especially compared to other metals such as silver, commonly used connection methods, especially soldering, have the disadvantage of forming contacts with low mechanical stability and relatively high contact resistance. Therefore, it is known to provide so-called "solder pads" made of another metal to form stable conductive connections with low contact resistance.

[0057] The present invention has the advantage that extensive coverage of the back surfaces of the solar cells of a solar cell string by the cross-connector allows for the creation of mechanically stable, low-resistance contacts directly on the aluminum back surfaces of the solar cells, since the large surface area ensures advantageous mechanical stability and electrical performance of the contacts, which is further improved by the advantageous configuration of the cross-connect's partial area of ​​the aforementioned metallic back contact structure.

[0058] In an advantageous development of the solar cell module according to the invention, at least the solar cells of the solar cell row in which the cross connector is arranged are each provided with an aluminum back contact on their back surface, the back contact preferably covering at least 60%, particularly preferably at least 80%, of the back surface of the solar cell, in particular the aluminum back contact is formed over the entire surface. The cross connector is arranged on the back contact and is directly electrically conductively connected to the aluminum back contact.

[0059] To form an efficient matrix shingle configuration, it is advantageous for at least one non-edge solar cell in each solar cell row of the solar cell module to cover at least two solar cells in an adjacent solar cell row in the overlap region, except for one edge solar cell row.

[0060] Advantageously, the cross-connectors are mechanically connected to the solar cells over at least 80% of the surface, more preferably at least 90% and particularly preferably 100% of the surface, that the cross-connectors cover on the back side of the solar cells of the solar cell string, which ensures high mechanical stability.

[0061] In order to form a low contact resistance, it is advantageous for the cross connector to be electrically connected to the solar cells over at least 80% of the surface covering the back surface of the solar cells in the solar cell string, more preferably at least 90% of the surface, and particularly preferably 100% of the surface.

[0062] In an advantageous embodiment, the solar cell module has one conductive cross-connector in each of at least two solar cell rows at both ends, which electrically connects and covers at least 50% of the back surface of at least the solar cells that are not on the edge of the solar cell row. The cross-connectors are used to connect the solar cell module to an external circuit or another solar cell module. In this embodiment, the solar cell row at the edge that overlaps the adjacent solar cell row on its back surface is inactive, i.e., it does not contribute to the conversion of electromagnetic radiation into electrical energy. This embodiment features a visually uniform front surface due to the cross-connectors in the edge solar cell rows, while also allowing for simple interconnection.

[0063] The percentages for forming metallic contact structures are by mass percentage.

[0064] The solar cell module may have an encapsulation element known per se. In particular, it is within the scope of the present invention for the solar cell module to have, in order from the side facing the radiation in use, at least one, preferably all, of the following layers: ·Front glass (PV windshield) Front encapsulation foil (PV encapsulation foil), preferably made of ethylene vinyl acetate (EVA) or polyolefin elastomer (POE) Solar cells in solar modules preferably made of silicon In the area of ​​the cross-connectors: preferably copper cross-connectors Back encapsulation foil (PV encapsulation foil) preferably made of ethylene vinyl acetate (EVA) or polyolefin elastomer (POE) ·Back cover (PV back sheet) preferably made of polyethylene (PE) or polyethylene terephthalate (PET) [Brief explanation of the drawings]

[0065] Further advantageous features and embodiments are explained below on the basis of example embodiments and drawings. [Figure 1] 1 is a photovoltaic solar cell for a first example embodiment of a solar cell module according to the invention. [Figure 2] 1 is a side view of a first embodiment of a solar cell module according to the present invention; [Figure 3] 1 is a plan view of a first embodiment of a solar cell module according to the present invention, seen from the rear. [Figure 4] FIG. 2 is a rear plan view of a second embodiment of a solar cell module according to the present invention. [Figure 5] FIG. 10 is a rear plan view of a second and third embodiment of a solar cell module according to the present invention. [Figure 6] Photovoltaic solar cells for solar cell modules according to Figure 7. [Figure 7] FIG. 10 is a rear plan view of a fourth embodiment of a solar cell module according to the present invention. [Figure 8] FIG. 10 is a rear plan view of a fifth embodiment of a solar cell module according to the present invention. [Figure 9] 9 is a cross-sectional view of FIG. 8, each cross-section being perpendicular to the plane of the drawing in FIG. 8. [Figure 10] 9 is a cross-sectional view of FIG. 8, each cross-section being perpendicular to the plane of the drawing in FIG. 8. [Figure 11] 9 is a cross-sectional view of FIG. 8, each cross-section being perpendicular to the plane of the drawing in FIG. 8. DETAILED DESCRIPTION OF THE INVENTION

[0066] All figures are drawn in a schematic and not to scale manner, and the same reference numerals in the figures indicate elements that are the same or have the same effect.

[0067] 1 shows a schematic representation of a photovoltaic solar cell 1 for a first embodiment of a solar cell module according to the invention in a plan view from the front. The solar cell 1 has a metallic contact structure on the front side, which is formed in a comb-like shape in a known manner and has a plurality of parallel-extending contact fingers 2, which are electrically conductively connected by bus bars 3 extending perpendicularly to the contact fingers 2.

[0068] The solar cell 1 is formed in a manner known per se as a photovoltaic solar cell based on a silicon wafer as semiconductor substrate and has an emitter that is contacted on the front side by contact fingers 2 and a busbar 3. The rear side of the solar cell is provided with an aluminum layer over the entire surface for electrical contact with the substrate of the solar cell. It is within the scope of the invention to use developments of this solar cell structure or other solar cell structures as solar cells in solar cell modules according to the invention. In particular, it is within the scope of the invention to arrange additional layers on the front side to improve the electrical performance, in particular to reduce the recombination rate at the surface, or to improve the visual properties.

[0069] The solar cell illustrated in Figure 1 is a sub-solar cell that has been fabricated by dividing a larger silicon substrate on which multiple sub-solar cells have been formed. It is also within the scope of the present invention to use solar cells formed entirely on an undivided silicon wafer.

[0070] In FIG. 1, an overlapping region 4 is indicated by a dashed line, and because of the single structure, the back surface of the adjacent solar cell in the overlapping region overlaps with the front surface of the solar cell shown in FIG.

[0071] A schematic representation of a first embodiment of a solar cell module according to the invention is shown in a side view in FIG. 2 and in a plan view from the rear in FIG. 3: The solar cell module according to the first embodiment comprises a plurality of photovoltaic solar cells 1 according to FIG. 1, each having an electrically contactable back surface which is covered over the entire surface with an aluminium layer.

[0072] The solar cells 1 are arranged in a matrix-shingle configuration, here with three spatially parallel arranged solar cell rows, each row containing a plurality of solar cells.

[0073] In FIG. 3, it can be seen that the bottom and top rows of the solar cell rows arranged spatially parallel in the representation of FIG. 3 each have five solar cells, and the middle solar cell row has four solar cells 1.

[0074] As can be seen in FIG. 2, the solar cell rows are arranged to overlap in the overlap region 4 so that the back surface of a solar cell 1 in one solar cell row partially covers the front surface of a solar cell 1 in an adjacent solar cell row.

[0075] Furthermore, the solar cells are arranged such that the back surface of at least one solar cell in one solar cell row partially covers the front surfaces of at least two solar cells in the adjacent solar cell row, e.g., in the embodiment according to Fig. 3, solar cell 1a partially covers solar cells 1d and 1e, solar cell 1b partially covers solar cells 1e and 1f, and solar cell 1c partially covers solar cells 1f and 1g.

[0076] To form this partial covering, the edge solar cells 1 of the bottom and top solar cell rows according to FIG. 3 are formed to have only half the width of the other solar cells 1 of the solar module.

[0077] What is important is that the solar cell module has conductive cross connectors 5 that cover and electrically contact at least 50% of the back surface of each solar cell 1 in the middle solar cell row. In this embodiment, the solar cell row contacted by the cross connector has four solar cells 1. Here, solar cells 1e and 1f that are not on the edges are covered by the cross connector by approximately 80% (the drawing is not to scale), as is solar cell 1g on the right edge, according to Figure 3, where the cross connector 5 extends beyond the right edge of the solar cell 1 for contact. In the case of solar cell 1d on the left edge, the cross connector is spaced from the left edge of the solar cell, resulting in slightly less coverage.

[0078] The cross connector 5 is formed as an electrically conductive adhesive tape and extends beyond the surface of the solar cells at the right edge of the solar cell module according to FIG. 3, thereby allowing for a simple interconnection to other electronic elements at the side, in particular the bypass diodes of the solar cell module.

[0079] In Figure 3 a circuit diagram is shown schematically with two bypass diodes 6, one connected between the lower terminal of the solar module and the cross connector 5 and a second connected between the cross connector 5 and the upper terminal of the solar module.

[0080] In a variant of the first embodiment of the solar cell module according to the invention, the cross connectors 5 are formed as copper foils with a thickness of 30 μm. A conductive adhesive is arranged between the cross connectors 5 and the solar cells 1 of the intermediate solar cell string. In a subsequent method step in the production of the solar cell module, lamination is carried out by methods known per se. For this purpose, a transparent carrier substrate (glass) of the solar cell module is arranged on the front side, and a protective cover (backsheet) on the rear side. A front encapsulation foil (EVA) is arranged between the carrier substrate and the solar cells, and a rear encapsulation foil (EVA) is arranged between the solar cells and the backsheet. The foils are bonded by lamination, so that the solar cells 1 and the cross connectors 5 are embedded between them. In this variant of the first embodiment, the conductive adhesive applied between the cross connectors 5 and the solar cells 1 of the intermediate solar cell string also hardens during lamination.

[0081] Two further exemplary embodiments of a solar cell module according to the invention are illustrated in Figures 4 and 5. To avoid repetition, only the most important modifications will be mentioned.

[0082] The example embodiments shown in Figures 4 and 5 also use photovoltaic solar cells 1 arranged in the matrix-shingle configuration shown in Figure 1. The example embodiments shown in Figures 4 and 5 each have seven parallel solar cell rows, and as in the first example embodiment, the solar cell rows alternate between five and four solar cells, with the width of each edge solar cell in the five solar cell row being only half that of the other.

[0083] In the second embodiment shown in Figure 4, cross connectors 5 formed as conductive adhesive tapes are arranged in the second and sixth rows, respectively. In this embodiment, the cross connectors do not protrude beyond the solar cell surface. A junction box 7 containing bypass diodes is arranged in the center of the rear surface of the solar cell module.

[0084] The electrical supply from both cross connectors 5 to the junction box 7 is carried out by two longitudinal connectors 8 formed as copper tapes. A bypass diode arranged in the junction box 7 is electrically connected to the longitudinal connectors 8, so that one bypass diode is inserted between both cross connectors 5.

[0085] A third embodiment of a solar cell module according to the present invention, shown in rear view in Figure 5, has three cross connectors 5. The cross connectors 5 are arranged in the first, fourth, and seventh solar cell rows. The solar cell module also has a central junction box 7 and two vertical connectors 8. Two bypass diodes 6 are arranged in the junction box 7: the first bypass diode 6 is conductively connected between the lower vertical connector 8 and the middle cross connector 5, and the second bypass diode 6 is conductively connected between the middle cross connector 5 and the upper vertical connector 8. A schematic diagram of the resulting electrical circuit is shown by way of example at the left edge of Figure 5.

[0086] In FIG. 6 a plan view of the backside of a photovoltaic solar cell 1 for a fourth embodiment of a solar cell module according to the invention is shown.

[0087] The front configuration of the photovoltaic solar cell illustrated in FIG. 6 corresponds to the solar cell 1 illustrated in FIG.

[0088] 6, in contrast to the solar cell shown in Fig. 1, has a metallic back contact structure 9 with cross-connect arches, typically made of silver, arranged on the aluminum layer on the back side, and the back contact structure 9 has bus bars 9a and cross-connect arches 9b extending from the bus bars 9a to the back side of the solar cell.

[0089] In Figure 6, the dotted lines indicate that in the case of a matrix single connection of solar cells 1 as shown in Figure 6, in the series connection partial region 10, the bus bar 9a in particular is in close contact with the front surface of the adjacent solar cell 1, and the cross-connect partial region 11, which basically includes the cross-connect arch 9a, is covered by one cross-connector 5 and is directly and conductively connected to the cross-connector 5.

[0090] In Figure 7, a back view of the fifth example embodiment is shown. The fifth example embodiment is an extension of the third example embodiment shown in Figures 1 to 3. This extension relates to a back contact structure 9 with busbars 9a and cross-connect arches 9b, as described in relation to Figure 6. As shown in Figure 7, only the solar cells 1 in the central solar cell row have the back contact structure 9. In the back view, only the cross-connect arches 9b are still visible. For better visibility, only two cross-connect arches 9b are shown per full-width solar cell 1 and one cross-connect arch 9b per half-width solar cell 1 (edge ​​solar cell).

[0091] The cross-connector 5 essentially covers the cross-connect arch 9b, and in the representation in Figure 7, the cross-connect arch 9b is completely illustrated even in the area covered by the cross-connector 5 in order to clearly illustrate the arrangement of the cross-connect arch 9b.

[0092] In Figure 8 a rear view of a fifth embodiment of a solar cell module according to the invention is shown. The structure basically corresponds to that of the solar cell module shown in Figure 4. To avoid repetition, only the most important differences are mentioned: The solar cell module has 27 solar cell strings, each containing seven adjacent solar cells. Four cross connectors 5 are arranged on the back surface of the solar cells. The cross connectors 5 are electrically connected by vertical connectors 8. A junction box 7 is arranged in the center between each pair of cross connectors 5, and the cross connectors 8 are connected to the junction box. A bypass diode is arranged in each junction box 7, and the bypass diode couples the vertical connectors 8 connected to the junction box 7. For clarity, the interconnections using the bypass diodes 6 are shown schematically as an equivalent circuit diagram on the right edge.

[0093] Thus, the solar module according to Fig. 8 has a total of four vertical connectors 8: the edge cross connectors 5 are each connected to the nearest junction box 7 by one vertical connector 8. The central junction box 7 is connected to the upper and lower junction boxes 7 by one vertical connector 8 each, as shown in Fig. 8.

[0094] In this display, for ease of viewing, one solar cell is shown in the upper left corner, labeled with the reference numeral 1.

[0095] The solar cell module shown in Figure 8 has a plurality of cover strips 12 arranged between the solar cells 1 and the cross connectors 5 in the region where the cross connectors 5 extend across the space between two adjacent solar cells 1 of a solar cell row. Therefore, from the front side of the solar cell module, the cross connectors 5 in the spaces between the solar cells are covered by the cover strips 12. The cover strips are here colored black. Furthermore, the cover strips are electrically insulating to prevent unwanted currents. For clarity, only the cover strips 12 at the top and bottom edges of the solar cell module are labeled.

[0096] Figures 9 to 11 show cross-sectional views of the solar cell module shown in Figure 8. The cross-sections are each perpendicular to the plane of the drawing in Figure 8. Figure 9 shows a cross-section along section line A in Figure 8, Figure 10 shows a cross-section along section line B in Figure 8, and Figure 11 shows a cross-section along section line C in Figure 8. Therefore, the cross-sectional plane in Figure 11 is perpendicular to the cross-sectional planes in Figures 9 and 10.

[0097] 9 shows a cross section along section line A in the region where the cross connector 5 intersects with the vertical connector 8. Therefore, in FIG. 8, the second cross connector 5 from the bottom is shown without diagonal hatching for clarity.

[0098] As can be seen in FIG. 8, the cross connectors 5 cover the vertical connectors 8, so that the vertical connectors 8 are disposed between the solar cells 1 and the cross connectors 5 in the covered area.

[0099] As can be seen in FIG. 9, the solar cell module has the following layers, starting from the back side: Back cover 13 (e.g., made of PE or PET) of approximately 400 μm Approximately 400 μm back encapsulation foil 14 (e.g., made of EVA or POE) Solar cell 1 (e.g., silicon) of a solar cell module of approximately 180 μm A front encapsulation foil 15 (made of, for example, EVA or POE) of approximately 400 μm and a front glass 16 of approximately 3.2 mm Furthermore, at the position of cross section A, a cross connector 5 and a vertical connector 8 are arranged so as to intersect with each other at the position of cross section A.

[0100] In addition, the insulating foil 17 of the vertical connector is arranged as an insulating element between the vertical connector 8 and the solar cell 1, and the insulating foil 17 of the vertical connector excludes at least the area where the cross connector 5 covers the vertical connector 8. Thus, a conductive connection is formed between the cross connector 5, the vertical connector 8 and the solar cell 1.

[0101] Thus, the cross connectors 5, the vertical connectors 8 and the insulating foils 17 of the vertical connectors are arranged between the back encapsulating foil 14 and the solar cells 1 in this order.

[0102] In FIG. 8, the full-length rear cover 13 and rear encapsulation foil 14 are not shown.

[0103] The cross section along section line B in FIG. 10 shows the area where the cross connector 5 is in direct contact with the solar cell 1 .

[0104] A cover strip 12 is positioned at the position of the cross section line C. The cover strip is positioned between the cross connectors 5 and the solar cells 1, so that when viewed from the front, or when viewed from below in Figure 11, the cross connectors 5 are covered by the cover strip 12 in the spaces between the solar cells 1, resulting in a visually uniform appearance. [Explanation of symbols]

[0105] 1. Solar cells 2 contact fingers 3, 9a busbar 4 Overlapping area 5 Cross Connector 6. Bypass diodes 7 Junction box 8 Vertical Connectors 9 Back contact structure 9b Cross Connect Arch 10 Series Connection Subregion 11 Cross-connect subarea 12 cover strips 13 Back cover 14 Backside foil 15 Front-inserted foil 16 Front glass 17 Insulating foil of vertical connector

Claims

1. 1. A solar cell module having a plurality of photovoltaic solar cells having back surfaces that are electrically contactable, The solar cells are arranged in a matrix shingle configuration having a plurality of spatially parallel solar cell rows, each row including a plurality of solar cells, and the solar cell rows are arranged to overlap at an overlap region, such that the back surface of the solar cell in one solar cell row partially covers the front surface of the solar cell in an adjacent solar cell row; In a solar cell module, the solar cells are arranged so that at least one back surface of one solar cell (1) in one solar cell row partially covers the front surfaces of at least two solar cells in an adjacent solar cell row, A solar cell module characterized in that at least one solar cell row has a conductive cross connector (5) that covers and electrically contacts at least 50% of the back surface of each of the solar cells (1) that are not on the edge side of the solar cell row.

2. 2. The solar cell module according to claim 1, characterized in that the cross connectors (5) cover and electrically contact at least 60%, preferably at least 70%, in particular at least 80% of the rear surface of each of the solar cells that are not on the edge side of the solar cell row.

3. 3. The solar module according to claim 1, wherein the cross-connector (5) is formed as an electrically conductive adhesive tape.

4. 4. The solar cell module according to claim 1, wherein the cross connectors (5) are arranged mechanically and electrically conductively to the solar cells using a conductive adhesive, in particular the cross connectors (5) are formed as metal foils.

5. 5. The solar cell module according to claim 1, wherein the solar cell module has at least one electrically conductive vertical connector (8) that is electrically connected to the cross connector (5) of one solar cell row, the vertical connector (8) extending across another solar cell row and / or another cross connector (5) of the solar cell module, preferably the vertical connector (8) being electrically insulated from the other solar cell row and / or the other cross connector of the solar cell module by an electrical insulating layer.

6. 6. The solar cell module according to claim 5, characterized in that the solar cell module has one connection box (7) in each of at least two solar cell rows, and the vertical connector (8) extends between the connection boxes and, in particular, conductively connects the electrical terminals of both of the connection boxes.

7. The cross connector (5) is electrically connected to the bypass diode (6) of the solar cell module, and in particular 7. The solar cell module according to claim 1, wherein the solar cell module has two solar cell strings each including one cross connector (5), and the bypass diodes (6) are electrically coupled to the cross connectors.

8. 8. The solar cell module according to claim 1, wherein the cross-connector (5) is arranged in a solar cell row on the edge of the solar cell module and is electrically conductively connected to an external electrical element, in particular an external discharge connection and / or a connection element for interconnecting the solar cell module to another solar cell module.

9. 9. A solar cell module according to claim 1, wherein the cross connectors (5) on the side of the solar cell row facing the solar cells are formed in blue or black, preferably black, at least in the spaces between the solar cells, preferably over the entire surface.

10. At least the solar cells of the solar cell row in which the cross connector (5) is arranged each have a metallic back contact structure (9), the back contact structure extending over the overlapping region (4) onto the back surface of the solar cell (1) so that a partial region (10) of the metallic back contact structure (9) for the series connection is in close contact with the front surface of the adjacent solar cell (1) in the overlapping region (4), and a partial region (11) of the metallic back contact structure (9) for the cross connection is covered by the cross connector (5) and is directly conductively connected to the cross connector, in particular 10. Photovoltaic module according to any one of claims 1 to 9, characterized in that the metallic back contact structure (9) is formed to an extent of at least 50% from metals of the group consisting of silver and copper.

11. 11. A solar cell module according to claim 1, wherein at least on the back surface of the solar cell row where the cross connector (5) is arranged, the solar cells each have a back surface contact surface made of aluminum, and the cross connector (5) is arranged on the back surface contact surface and is directly conductively connected to the back surface contact surface.

12. arranging the plurality of solar cells in a matrix shingle configuration to form a plurality of spatially parallel solar cell rows, each having a plurality of solar cells, the solar cell rows being arranged to overlap at an overlap region such that the back surfaces of the solar cells in one solar cell row partially cover the front surfaces of the solar cells in an adjacent solar cell row; The solar cells are arranged such that at least one back surface of one solar cell (1) in one solar cell row partially covers the front surfaces of at least two solar cells in an adjacent solar cell row, A method comprising arranging conductive cross connectors (5) in at least one solar cell row, each of which covers at least 50% of the back surface of the solar cells (1) that are not on the edge side of the solar cell row, and making electrical contact with the back surface of the solar cells (1).

13. 13. The method according to claim 12, characterized in that the cross-connectors (5) are formed so as to cover and electrically contact at least 60%, preferably at least 70%, in particular at least 80% of the rear surface of each of the solar cells in the solar cell string that is not at the edge.

14. 14. Method according to claim 12 or 13, characterized in that a conductive adhesive tape is used as the cross-connector (5).

15. The cross connector (5) is placed on the solar cell using a conductive adhesive and is electrically connected to the solar cell; 14. The method according to claim 12 or 13, characterized in that the curing of the conductive adhesive is carried out during lamination of the solar module.

16. 12. The solar cell module according to claim 1, wherein at least the solar cells in the solar cell row in which the cross connector (5) is arranged each have a metallic back contact structure, the back contact structure extends beyond the overlap region onto the back surface of the solar cell so that a partial region of the series connection in the metallic back contact structure is in close contact with the front surface of the adjacent solar cell in the overlap region, and a partial region of the cross connect in the metallic back contact structure is covered by the cross connector (5) and is directly conductively connected to the cross connector.

17. 12. A solar cell module according to claim 1, wherein the cross connector (5) is mechanically connected to the solar cells over at least 80% of the surface covering the back surface of the solar cells of the solar cell row, more preferably at least 90% of the surface, and particularly preferably 100% of the surface.

18. The vertical connector (8) is arranged between the solar cell and the cross connector (5), 6. The solar cell module according to claim 5, wherein the vertical connectors (8) are electrically connected to the solar cells in the area where the cross connectors (5) cover the vertical connectors (8).

Images