DE102008050332A1 - Photovoltaic cell comprises a photovoltaic conversion layer, a lower electrode layer applied on a lower surface of the photovoltaic conversion layer, and a multilayer foil applied on an upper surface of the photovoltaic conversion layer - Google Patents

Abstract

The photovoltaic cell (11) comprises a photovoltaic conversion layer (23), a lower electrode layer (20), which is applied on a lower surface of the photovoltaic conversion layer, and a multilayer foil (30), which is applied on an upper surface of the photovoltaic conversion layer and projects the photovoltaic conversion layer into a first zone, so that the multilayer foil in the first zone is not covered by the photovoltaic conversion layer. The multilayer foil has a carrier foil, and an electrode layer having contact electrodes made of an electrically conducting material (7). The photovoltaic cell (11) comprises a photovoltaic conversion layer (23), a lower electrode layer (20), which is applied on a lower surface of the photovoltaic conversion layer, and a multilayer foil (30), which is applied on an upper surface of the photovoltaic conversion layer and projects the photovoltaic conversion layer into a first zone, so that the multilayer foil in the first zone is not covered by the photovoltaic conversion layer. The multilayer foil has a carrier foil, an electrode layer having contact electrodes made of an electrically conducting material (7), an electrically conducting additional layer, which is arranged between the carrier foil and the electrode layer and is formed, so that it covers the contact electrodes in an area-wise manner and electrically contacts with one another, and a partial adhesive layer, which is arranged in areas of the multilayer foil not covered with the contact electrodes. The photovoltaic conversion layer consists of organic or inorganic electrically semiconducting material and/or has multiple layers. The photovoltaic cell has a carrier substrate arranged below the lower electrode layer. The multilayer foil completely covers the photovoltaic conversion layer. The contact electrodes are contacted with the photovoltaic conversion layer. The additional layer area-wisely covers the carrier foil in a second zone, which projects a boundary line between the first zone and the area of the photovoltaic conversion layer covered by the multilayer foil to 1-3 mm on both sides, and/or covers the carrier foil in the first zone. An independent claim is included for a multilayer foil.

Description

The The invention relates to a photovoltaic cell and a multilayer film for producing such a cell.

The structure of a photovoltaic cell, for example, in the US Pat. No. 6,822,158 B2 described. The photovoltaic cell is composed of a transparent upper electrode layer, a photovoltaic conversion layer, a backside transparent electrode layer, and a backside reflective metal layer. These layers are deposited on a transparent carrier substrate in the order described above. The transparent back electrode consists of two layers, wherein an ITO (ITO = indium tin oxide (indium tin oxide)) layer is adjacent to the photovoltaic conversion layer and a layer of ZnO is adjacent to the ITO layer. In this case, the transparent electrode layers are applied to the photovoltaic conversion layer by means of magnetron sputtering.

adversely At such constructed photovoltaic cells is that by environmental influences during operation of the solar cell contacting problems between photovoltaic Conversion and the electrode layers can occur and complex manufacturing processes for the production the photovoltaic cell are needed.

Of the Invention is now the object of an improved photovoltaic Cell and the production of photovoltaic cells to improve.

These Task is a photovoltaic cell comprising a photovoltaic Conversion layer and a lower electrode layer, which on a lower surface of the photovoltaic conversion layer is applied, dissolved, which comprises a multilayer film, which on a top surface of the photovoltaic Conversion layer is applied and the photovoltaic conversion layer surmounted in at least a first area, so that the Multilayer film in the first area not from the photovoltaic Conversion layer is covered, wherein the multilayer film has a Carrier film comprising an electrode layer, a plurality of Contact electrodes, formed from an electrically conductive Material, an electrically conductive additional layer, the disposed between the carrier foil and the electrode layer is and which is shaped so that it has two or more of the contact electrodes at least partially covered and electrically interconnected contacted, and a partial adhesive layer, which in not With the contact electrodes covered areas of the multilayer film is arranged. This object is further from a multilayer film, in particular a laminating film, for bonding with a photovoltaic Conversion layer of a photovoltaic cell solved, comprising a carrier foil, an electrode layer a plurality of contact electrodes formed from an electrically conductive Material, an electrically conductive additional layer, the disposed between the carrier foil and the electrode layer is and which is shaped so that it has two or more of the contact electrodes at least partially covered and electrically interconnected contacted, and a partial adhesive layer, which in not With the contact electrodes covered areas of the multilayer film is arranged.

According to the invention Thus, the upper electrode layer is provided by a multilayer film, which two conductive layers, one electrode layer with contact electrodes and an electrically conductive additional layer comprises and by means of a partial adhesive layer on the surface the photovoltaic conversion layer is set between the electrically conductive additional layer and the photovoltaic Conversion layer in not covered with the contact electrodes Regions of the multilayer film is arranged. The upper electrode layer Thus, by laminating a the photovoltaic conversion layer applied in at least the first area superior multilayer film, the two differently structured electrically conductive Includes layers, one of which is the surface of the photovoltaic Conversion layer contacted and the other, above the partial Adhesive layer is arranged, areas of the lower electrically conductive Layer electrically contacted each other. By such Construction will be both a particularly durable and too Production error to some extent compensating contact achieved the photovoltaic conversion layer. By the special On the one hand, the structure of the multi-layered film is caused by problems the occurrence of cracks and separation phenomena in the contact areas of the photovoltaic conversion layer and the electrode layer can occur, largely avoided and on the other a low-resistance and opposite Microcracks provided largely fault-resistant power dissipation.

The Contact electrodes are preferably made of a metallic material a layer thickness of more than 5 microns, preferably a layer thickness between 20 μm and 50 μm. This will both on the one hand a low-resistance electrical connection, as well as a sufficient Flexibility of the electrode layer ensures that for the manufacture of photovoltaic devices on flexible Carriers is of crucial importance ..

Preferably, the contact electrodes are in Form of finger electrodes molded.

The electrically conductive additional layer is preferably from a transparent, electrically conductive material. The electrically conductive additional layer consists for example from an ITO layer or IMI layer (IMI = ITO metal ITO), preferably with a thickness between 50 nm and 120 nm. It is also possible that the electrically conductive additional layer of a thin and thus transparent metallic layer. Further But it is also possible that the electrically conductive Additional layer of a structured and thus semitransparent metallic layer. It is in this context too possible that the electrically conductive layer is formed of several layers.

According to one preferred embodiment of the invention exist the contact electrodes and the electrically conductive additional layer made of different materials and / or the layer thickness of Contact electrodes and the electrically conductive additional layer differs by more than 90%. For this purpose, it is advantageous as electrically conductive material for the additional layer to choose a transparent or largely transparent material and for the contact electrodes, an opaque material with high electrical To use conductivity.

Preferably The additional layer covers the carrier film over its entire surface. This has the advantage that the photovoltaic cell is particularly resistant against environmental influences and production errors is.

According to one preferred embodiment of the invention covered the electrically conductive additional layer, the carrier film only partially. For this purpose, it is advantageous if the additional layer covers the carrier film in a second area, which the boundary lines between the first region and that of the multilayer film covered area of the photovoltaic conversion layer on both sides at least 1 mm, preferably surmounted between 1 mm and 3 mm. investigations have shown that the life of photovoltaic cells already significantly increased by this measure can be, so with less material consumption and at higher Luminous efficiency than in a full-surface arrangement of Additional layer by this measure a substantial increase the lifetime can be achieved.

According to one preferred embodiment of the invention is the Additional layer at least partially formed in the form of a grid, which is formed by a multitude of intersecting grid lines is made of the conductive material, or is at least partially in the form of a variety of linear Formed areas. Such an embodiment of the electric conductive additional layer brings particular advantages with, if the electrically conductive additional layer due to the electrically conductive material, for example Metal, and the selected thickness of the electrically conductive Additional layer opaque or of low transparency - so semitransparent - for the wavelength range is, to which the photovoltaic conversion layer is tuned. By such a configuration of the electrically conductive Additional layer can on the one hand still have a good average transparency, as well as a low-resistance nationwide electrical Connection of the contact electrodes can be achieved.

Preferably is the grid a regular one Grid with a periodic sequence of grid lines in one first and a second direction parallel to that of the multilayer film lie spanned plane. It is also possible and as explained below advantageous, the width the grid lines and / or the spacing of the grid lines in the first and / or second direction depending on the Location coordinates in the plane spanned by the multilayer film to vary.

Preferably the first direction closes an angle between 80 ° and 100 ° with the contact electrodes or the linear one Areas with an angle between 45 ° and 135 ° the contact electrodes, more preferably a right angle with the contact electrodes. As a result, a particularly low-impedance achieved electrical connection between the contact electrodes of the electrode layer.

The Line-shaped regions further preferably extend over the entire width of the carrier film and are more preferred arranged substantially parallel to each other.

According to a preferred embodiment of the invention, in one or more outer regions of the multilayer film, the width of the grid lines or of the linear regions is higher than in an inner region of the multilayer film and / or in one or more outer regions the line spacing of the grid lines or of the linear regions is lower than in the inner region of the multilayer film. The width of the grid lines or line-shaped areas and their spacing is accordingly dependent on the location coordinate within the plane spanned by the multilayer film. The outer regions of the multilayer film in which the width of the grid lines or line-shaped regions increases or the spacing of the grid lines or linear regions are reduced are preferably first regions in which the multilayer film is not affected by the photovoltaic con Version layer is covered.

Such Outdoor areas are preferably also formed by areas which the boundary line between that of the multi-layer film covered Area of the photovoltaic conversion layer and the conversion layer superior Area of the photovoltaic conversion layer on both sides between 1 mm and 5 mm, preferably projecting from 1 mm to 3 mm.

Further It is also possible that such outdoor areas are formed by edge regions of the multilayer film, such Edge regions preferably have a width of 2 to 15 mm.

Preferably Here is the width of the grid lines or linear Areas and / or the spacing of the grid lines or linear Areas in the outdoor area more than twice as high or twice as low as in an inner area of the Multilayer film.

According to one preferred embodiment of the invention, the Electrode layer further at least one of the conductive Material of the electrode layer formed on connecting element, the two or more of the contact electrodes are electrically connected to each other combines. This at least one connecting element is in this case preferably arranged in the first area. This measure will the reliability of the photovoltaic cell further increased and sufficient drainage areas for disposal posed.

The Photovoltaic conversion layer is preferably made of a or more organic and / or inorganic electrically semiconductive materials. Furthermore, it is also advantageous if the photovoltaic conversion layer consists of several layers, for example of a multi-layer structure with P3HT (P3HT = poly (3-hexylthiophene)) and PCBM (PCBM = (6,6) -phenyl-C61-butyricacid-methyl-ester) as donor and acceptor materials or of an inorganic one Multilayer structures in the form of a CIS (CIS = copper indium selenide) or CIGS (Copper-Indium-Gallium-Selenide) construction. In this Context but also other structures are conceivable. The layer thickness the photovoltaic conversion layer, in particular the photovoltaic Konversionsschichtgebildes, for example, in the case of a predominantly organic structure in the range of about 1 to about 2 microns lie in the case of an inorganic structure, for example in the field from about 50 to about 500 microns.

The Contact electrodes of the electrode layer of the multilayer film are so through the partial adhesive layer on the surface the photovoltaic conversion layer is arranged and fixed, that they are at least partially in contact with the photovoltaic Conversion layer, preferably completely in contact are arranged with the photovoltaic conversion layer. The partial adhesive layer is thus preferably only in the Areas of the multilayer film provided, in which the multilayer film the photovoltaic conversion layer covers and no contact electrodes are provided. Preferably, the partial adhesive layer covers between 80% and 100% of this range. Preferably, the adhesive layer is between the areas of the additional layer that is not covered by the contact electrodes are provided, and the photovoltaic conversion layer.

The lower electrode layer of the photovoltaic cell is preferably from a full-surface metallic layer, which preferably is provided in a layer thickness that the lower electrode layer additionally the function of a carrier substrate provides. However, it is also possible that the other Electrode layer is formed multi-layered or that below the lower electrode layer an additional carrier substrate is provided, on which the lower electrode layer is applied is.

The Carrier film of the multilayer film is preferably made a transparent, flexible plastic film, preferably with a Layer thickness between 19 μm and 150 μm. It is this further also possible that in the carrier film or in the replicate varnish layer of the multilayer film, a surface structure is molded. This surface structure is preferable registered to the contact electrodes and / or the grid lines or linear areas of the electrically conductive Additional layer in the carrier film or the Replizierlackschicht shaped. The surface structure is in this case designed such that it has light-deflecting properties and in the area of contact electrodes or the grid lines or linear areas incident Deflects light and thus the efficiency of the photovoltaic cell elevated. The surface structures are preferably blaze lattices to lenticular structures or to diffractive structures, in particular kinoform, which accordingly are designed to distract the incident light in these areas.

in the The invention is based on several embodiments and exemplified with the aid of the accompanying drawings:

1a shows a sectional view of a first module formed from a plurality of photovoltaic cells according to the invention.

1b shows a sectional view of a second module formed from a plurality of photovoltaic cells according to the invention.

2a shows a schematic plan view of an electrode layer for a photovoltaic cell according to the invention.

2 B to d show sectional views of several embodiments of a photovoltaic cell according to the invention.

3a shows a plan view of a photovoltaic cell according to the invention for a further embodiment of the invention.

3b shows a sectional view of the photovoltaic cell after 3a ,

4a shows a plan view of a photovoltaic cell according to the invention for a further embodiment of the invention.

4b shows a sectional view of the photovoltaic cell after 4a ,

5a shows a plan view of a photovoltaic cell according to the invention for a further embodiment of the invention.

5b shows a sectional view of the photovoltaic cell after 5a ,

6 shows a plan view of a photovoltaic cell according to the invention for a further embodiment of the invention.

7 shows a plan view of a photovoltaic cell for a further embodiment of the invention.

8th shows a plan view of a photovoltaic cell for a further embodiment of the invention.

9 shows a plan view of a photovoltaic cell for a further embodiment of the invention.

The structure of a photovoltaic cell according to the invention 11 will be described below on the basis of 2 B and 2a explained.

2 B shows the photovoltaic cell 11 , The photovoltaic cell 11 consists of a photovoltaic conversion layer 23 , a lower electrode layer 20 and a multilayer film 30 , which on the light entrance side facing surface of the photovoltaic conversion layer 23 is laminated.

The lower electrode layer 20 is formed by a metallic layer of a layer thickness of 20 microns to 50 microns, preferably 25 microns. The electrode layer 20 is preferably made of titanium or other metallic material. Further, it is also possible that the lower electrode layer 20 is formed multi-layered and, for example, on the photovoltaic conversion layer 23 side facing a layer of a non-metallic, electrically conductive material, such as ITO has.

Further, it is also possible that the lower electrode layer 20 consists of a non-metallic, electrically conductive material or is applied to a preferably rigid carrier substrate.

The photovoltaic conversion layer 23 occupies the entire area between the two electrodes and is preferably formed of several layers.

• 1. einer Lochblockerschicht – beispielsweise TiOx;
• 2. einer aktiven Schicht bestehend aus einem Gemisch aus P3HT und PCBM;
• 3. einer Elektrodenblockerschicht – beispielsweise PEDOT:PSS.

The photovoltaic conversion layer 23 preferably consists of an inorganic semiconductor, for example a monocrystalline, polycrystalline, microcrystalline or amorphous silicon layer with a layer thickness of between 50 μm and 500 μm. Furthermore, it is also possible for the photovoltaic conversion layer to consist of an organic semiconductor layer or of a sequence of several organic layers, which are excited to charge separation by incident light quanta. For example, it is possible that the photovoltaic conversion layer 23 consists of a sequence of the following layers:

• 1. a hole blocking layer - for example TiOx;
• 2. an active layer consisting of a mixture of P3HT and PCBM;
• 3. an electrode blocker layer - for example PEDOT: PSS.

The multilayer film 30 has a carrier film 31 , an electrically conductive additional layer 32 , an electrode layer 33 and a partial adhesive layer 34 on.

The carrier foil 31 consists of a transparent, flexible plastic film, for example, with a layer thickness of 19 microns to 150 microns. In the carrier film 31 This is, for example, a PET or BOPP film with a layer thickness of 19 μm to 150 μm.

On the carrier foil 31 then becomes the electrically conductive additional layer 32 applied. Thus, in this embodiment, the carrier film 31 as an electrically conductive additional layer 32 full surface of a layer of a transparent electric applied conductive material. For example, an ITO or IMI layer with a layer thickness between 50 nm and 120 nm, preferably between 50 nm and 80 nm, is applied.

On the additional layer 32 then the electrode layer is applied. The electrode layer is here as in 2a illustrated formed. The electrode layer has a plurality of contact electrodes formed of a conductive material 33 on, by a formed of the electrically conductive material electrical connection element 35 connected to each other. The electrically conductive material from which the contact electrodes 33 and the connecting element 35 are formed, is preferably a metal system, for example silver, which in a layer thickness of more than 5 microns on the additional layer 32 is applied over a silver screen printing paste. For example, in the area of the contact electrodes 34 and the connecting element 35 an electrically conductive material on the additional layer 32 applied and then by means of galvanic reinforcement, a metallic layer having a layer thickness of more than 5 .mu.m, preferably between 5 .mu.m and 50 .mu.m, more preferably deposited in about 25 microns. Furthermore, it is also possible to pattern the electrode layer by means of other methods onto the additional layer 32 applied. Thus, it is for example possible to provide the additional layer over the entire surface, for example by means of vacuum vapor deposition with a metal layer and then in the areas where neither the contact electrodes 33 still the connecting element 35 are provided to remove the metal layer, for example by means of etching or ablation, for example, laser ablation or mechanical ablation again. Furthermore, it is also possible for the electrode layer to be applied to the additional layer by means of a transfer film 32 is laminated.

In not with the contact electrodes 33 covered areas of the multilayer film is then the partial adhesive layer 34 applied. The partial adhesive layer 34 will, as in 2a clarified, for example in all areas of the multilayer film 30 on the additional layer 32 applied, not with the contact electrodes 33 and the connecting element 35 are covered. The adhesive layer 34 is, for example, by means of a registered printing method after application of the electrode layer on the additional layer 32 printed. As a printing method for this purpose, for example, a screen printing method, a gravure printing method or a tampon printing method can be used. Furthermore, it is also possible that the adhesive layer 34 imprinted over the entire area and then in the areas of the contact electrodes 33 and the connecting element 35 is removed again by means of a doctor blade. The adhesive layer remains in non-raised areas, ie in the areas where neither the contact electrodes 33 still the connecting element 35 is provided.

In the case of the adhesive layer 34 The adhesive used is preferably a hot melt adhesive, ie an adhesive activatable by heat and / or pressure. However, it is also possible that it is the adhesive of the adhesive layer 34 is a cold glue or a UV-activated adhesive. The layer thickness of the adhesive layer 34 This corresponds approximately to the layer thickness of the electrode layer 33 , It is also possible in this case that the application thickness of the adhesive layer 34 between 1% and 10% less than the layer thickness of the electrode layer 33 is. This ensures, on the one hand, that during the lamination of the multilayer film 30 the material of the adhesive layer 34 not in the contact area between contact electrodes 33 and photovoltaic conversion layer 23 is pressed. Further, this will be in the area of these contact surfaces after curing of the adhesive layer 34 by the thus generated bias in the carrier layer 31 generates a constant, increased contact pressure, which ensures a secure contact between contact electrodes 33 and surface of the photovoltaic conversion layer 23 ensures.

The multilayer film 30 In this case, it is preferably produced in a roll-to-roll process, with optionally a peelable protective layer on the underside of the multilayer film, in particular when using a cold adhesive for the adhesive layer 34 is applied. The multilayer film 30 is then on the photovoltaic conversion layer 23 laminated and this - depending on the adhesive used for the adhesive layer 34 - Under the action of pressure, heat and / or UV radiation on the surface of the photovoltaic conversion layer 23 applied. It is possible that the multilayer film 30 as a transfer layer of a transfer film on the surface of the photovoltaic conversion layer 23 is applied.

As in 2 B clarified, has the multi-layer film 30 a larger length dimension than the photovoltaic conversion layer 23 so that the multilayer film 30 the photovoltaic conversion layer 23 in one area 61 surmounted in which the underside of the multilayer film 30 not from the photovoltaic conversion layer 23 is covered. This area of the multilayer film 30 is preferably for electrical contacting of the photovoltaic cell 11 used, as will be explained in more detail below. It is also possible that the multilayer film 30 the photovoltaic conversion layer 23 projects beyond one or more sides, for example one of the photovoltaic conversion layer 23 especially on all sides superior brim or circumferential, protruding edge forms. Preferably, the more dominates layer film 30 the photovoltaic conversion layer 23 in this case only on one side of the photovoltaic cell, so that the area 61 is preferably formed strip-shaped or tab-shaped.

2c shows a further embodiment of a photovoltaic cell according to the invention, a photovoltaic cell 11 ' , The photovoltaic cell 11 ' is different from the photovoltaic cell 11 in that instead of the multilayer film 30 a multilayer film 30 ' on the photovoltaic conversion layer 23 is laminated, in which the electrically conductive additional layer 34 not over the entire surface, but only in one area 62 is provided. The area 62 is from an area of the photovoltaic cell 11 ' formed on both sides of the boundary line between the area in which the photovoltaic conversion layer 23 from the multilayer film 30 ' is covered, and the area where the multilayer film 30 ' the photovoltaic conversion layer 23 towers over. The area 62 extends from the boundary line toward the photovoltaic conversion layer 23 preferably 1 to 3 mm. Towards away from the photovoltaic conversion layer 23 can the area 62 until the end of the multilayer film 30 extend. The area 62 is thus preferably formed strip-shaped. By such a partial shaping of the additional layer 32 On the one hand already achieved a significant increase in the life of the photovoltaic cell and on the other hand reduces the cost of producing the photovoltaic cell due to the material savings achieved thereby. Furthermore, it is also possible to use an electrically conductive material of low transparency for the additional layer 32 to use without greatly impairing the effectiveness of the solar cell.

It is also possible that a differently shaped additional layer 32 is used, which is the carrier film 31 not completely covered. Preferably, this covers the additional layer 32 between 3% and 20% of the surface of the carrier film 31 , more preferably 5% to 8% of the surface of the carrier film 31 ,

2d illustrates another embodiment of a photovoltaic cell according to the invention, a photovoltaic cell 11 '' , The photovoltaic cell 11 '' points in contrast to the photovoltaic cell 11 a multilayer film 30 '' on, their extra layer 32 is formed in the form of a grid or in the form of a plurality of line-shaped areas. In this case, there is the additional layer 32 preferably of a metallic material, preferably with a layer thickness between 40 nm and 60 nm. The grid lines or the linear regions here preferably have a width between 50 .mu.m and 200 .mu.m, so that the width of the grid lines or linear regions below the resolution of the human Eye is lying. The grid lines or the line-shaped areas are preferably spaced apart from one another by 800 to 200 times their width, and are thus spaced apart, for example, by 1 to 1.5 cm. The line-shaped regions or the grid lines can be arranged in a periodic one- or two-dimensional sequence. Preferably, the spacing of the grid lines or the spacing of the linear areas is in an edge region 63 smaller than in an inner or central region of the multilayer film 30 '' like this in 2d is shown. In this case, it is advantageous in particular if the spacing of the grid lines or of the linear regions in the area is advantageous 61 and / or in one the boundary line between the photovoltaic conversion layer 23 outstanding areas of the multilayer film 30 '' and that of the photovoltaic conversion layer 23 covered areas of the multilayer film 30 '' is reduced on both sides superior areas, in particular by more than two times reduced. The region preferably projects beyond the borderline by more than 1 mm, preferably between 5 and 1 mm. Thus, the spacing of the grid lines or linear regions of the multilayer film is 30 '' for example, in one area 63 which results from the sum of the ranges set out above, as shown in FIG 2d is shown.

Furthermore, instead of or in addition to a reduction in the spacing of the grid lines or linear areas in such an edge area, it is also possible to increase the width of the grid lines or the linear area, in particular by more than two times. Furthermore, it is also possible for the grid to be of finer mesh in the edge regions and in the inner regions of the multilayer film 30 '' coarsely meshed is formed. In this case, the fine-meshed regions can completely enclose the coarse-meshed region and thus all edge regions of the multilayer film 30 '' taking.

From the photovoltaic cells 11 to 11 '' can be easily built photovoltaic modules, as shown in the figures 1a and 1b is clarified. The 1a shows one of a series connection of several photovoltaic cells 11 formed photovoltaic module 51 and 1b one of a series connection of several photovoltaic cells 11 formed photovoltaic module 52 , The photovoltaic cells 11 are like the figures 2a to 2d constructed and have the lower electrode layer 20 , the photovoltaic conversion layer 23 and the light that hits 1 facing multilayer film 30 on. The photovoltaic cells 11 are here about the areas 61 the multilayer film 30 contacted with each other, wherein in the contacting areas 70 and 71 During operation of the module strong mechanical alternating loads on the multilayer film 30 act. The contacting of the multilayer film 30 with the lower electrode of the subsequent photovoltaic cell 11 This is preferably done via an applied in the edge region electrically conductive material 7 The bottom of the area 61 the multilayer film 30 with the underside of the lower electrode of the subsequent photovoltaic cell 11 electrically contacted. Further, it is also possible that corresponding recesses in the carrier film 31 the multilayer film 30 in the area 61 are provided, which is a contacting of the contact electrodes 33 , of the connecting element 35 or the additional layer 32 with the lower electrode of the subsequent photovoltaic cell 11 enable.

3a and 3b illustrate the structure of a photovoltaic cell 12 ,

The photovoltaic cell 12 has a multilayer film 40 , the photovoltaic conversion layer 23 and the lower electrode layer 20 to 2 B on. The multilayer film 40 has the carrier film 31 , the electrically conductive additional layer 32 and an electrode layer with contact electrodes 41 and fasteners 42 . 43 , and 44 on. As in 3a and 3b shown, the electrically conductive additional layer over the entire surface of the carrier film 31 applied and consists of a transparent, electrically conductive material, as already after 2 B described. The connecting element 44 forms an outer contact region of the electrode layer and the connecting elements 42 and 43 contact the contact electrodes 41 with the connecting element 44 , As in 3b shown towers over the multilayer film 40 the photovoltaic conversion layer 23 both sides.

4a and 4b illustrate the structure of another photovoltaic cell 13 , The photovoltaic cell 13 is like the photovoltaic cell 12 to 3a and

3b built with the difference that the multilayer film 40 through the multilayer film 40 ' is replaced, in which the additional layer 32 not the entire surface of the carrier film 31 covered, but the additional layer 32 only in the area around the contact electrodes of the electrode layer, ie in the region of the connecting elements 44 is provided, as in 4a and 4b is clarified. Preferably, the additional layer 32 in this case in the region of the multilayer body 40 ' provided, which the photovoltaic conversion layer 23 surmounted.

5a and 5b illustrate the structure of another photovoltaic cell 14 , The photovoltaic cell 14 is like the photovoltaic cell 12 built, with the difference that the multilayer film 40 through the multilayer film 40 '' is replaced, in place of a full-surface additional layer 32 a shaped in the form of a grid additional layer 32 is provided.

7 shows a plan view of another photovoltaic cell 16 , The photovoltaic cell 16 is like the photovoltaic cell 14 formed, with the difference that the lattice-shaped additional layer 32 not in the entire area of the carrier film 31 is provided, but is provided only in an edge region of the multilayer film around the contact electrodes of the electrode layer.

6 illustrates the structure of a photovoltaic cell 15 , The photovoltaic cell 15 is like the photovoltaic cell 16 to 7 constructed, with the difference that in a first area, the electrically conductive additional layer as an electrically conductive additional layer 32 ' is formed in the form of a grid and in another area, the additional layer as an additional layer 32 is formed in the form of a fully electrically formed in this area transparent electrically conductive layer.

8th illustrates the structure of a photovoltaic cell 17 , The photovoltaic cell 17 is different from the photovoltaic cell 17 in that additionally in the carrier layer 31 a surface relief 81 is formed, which is the light pipe of light 1 through the carrier film 31 influences and thereby the effectiveness of the photovoltaic cell 17 elevated.

9 illustrates the structure of a photovoltaic cell 18 , The photovoltaic cell 18 is different from the photovoltaic cell 17 in that in addition partially in the carrier film an optically variable element 82 is molded, which the optical appearance of the photovoltaic cell 18 influenced in this area. The optically variable element is, for example, a hologram, which, for example, the authenticity of the photovoltaic cell 18 certified.

QUOTES INCLUDE IN THE DESCRIPTION

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Cited patent literature

• - US 6822158 B2 [0002]

Claims (28)

Photovoltaic cell ( 11 to 17 ) comprising a photovoltaic conversion layer ( 23 ), a lower electrode layer ( 20 ) located on a lower surface of the photovoltaic conversion layer ( 23 ), and a multilayer film ( 30 . 30 ' . 30 '' . 40 . 40 ' . 40 '' ), which on an upper surface of the photovoltaic conversion layer ( 23 ) is applied and the photovoltaic conversion layer in at least a first area ( 63 . 64 ), so that the multilayer film in the first region is not separated from the photovoltaic conversion layer ( 23 ), wherein the multilayer film ( 30 . 30 ' . 30 '' . 40 . 40 ' . 40 '' ) a carrier film ( 31 ), an electrode layer comprising a plurality of contact electrodes ( 33 . 41 ) formed from an electrically conductive material, an electrically conductive additional layer ( 32 . 32 ' ) between the carrier film ( 31 ) and the electrode layer and which is shaped so that it has two or more of the contact electrodes ( 33 . 41 ) at least partially covered and electrically contacted with each other, and a partial adhesive layer ( 34 ) not in contact with the contact electrodes ( 33 . 41 ) covered areas of the multilayer film is arranged. Photovoltaic cell according to claim 1, characterized in that the photovoltaic conversion layer ( 23 ) consists of at least one organic or at least one inorganic electrically semiconductive material and / or may be multi-layered. Photovoltaic cell after one of the preceding ones Claims, characterized in that the photovoltaic Cell further arranged below the lower electrode layer Carrier substrate has. Photovoltaic cell ( 11 to 18 ) according to one of the preceding claims, characterized in that the multilayer film ( 30 . 30 ' . 30 '' . 40 . 40 ' . 40 '' ) the photovoltaic conversion layer ( 23 ) completely covered. Photovoltaic cell ( 11 to 18 ) according to one of the preceding claims, characterized in that the contact electrodes or contact electrodes ( 33 . 41 ) at least partially in contact with the photovoltaic conversion layer ( 23 ) are arranged. Photovoltaic cell ( 11 ' . 11 '' ) according to one of the preceding claims, characterized in that the additional layer ( 32 ) the carrier foil ( 31 ) only partially covered, wherein the additional layer, the carrier film at least in a second area ( 62 ) covering the boundary line between the first area ( 61 ) and the area covered by the multilayer film of the photovoltaic conversion layer on both sides at least 1 mm, preferably between 1 mm and 3 mm. Photovoltaic cell according to one of the claims 1 to 5, characterized in that the additional layer, the carrier film only covered in the first area. Multilayer film ( 30 . 30 ' . 30 '' . 40 . 40 ' . 40 '' ), in particular laminating film for bonding with a photovoltaic conversion layer of a photovoltaic cell ( 11 to 18 ), wherein the multilayer film is a carrier film ( 31 ), an electrode layer comprising a plurality of contact electrodes ( 33 . 41 ) formed from an electrically conductive material, an electrically conductive additional layer ( 32 ) disposed between the support film and the electrode layer and formed so as to at least partially cover and electrically contact two or more of the contact electrodes, and a partial adhesive layer (FIG. 34 ) not in contact with the contact electrodes ( 33 . 41 ) covered areas of the multilayer film is arranged. Multilayer film according to claim 8, characterized in that the contact electrodes ( 33 . 41 ) consist of a metallic material and have a layer thickness of more than 1 micron. Multilayer film ( 30 . 40 ) according to claim 8 or claim 9, characterized in that the electrode layer further comprises at least one connecting element formed from the electrically conductive material ( 35 . 42 . 43 ) electrically connecting two or more of the contact electrodes. Multilayer body ( 30 ) according to claim 10, characterized in that the at least one connecting element in the first region ( 61 ) is arranged. Multilayer body according to one of claims 8 to 11, characterized in that the additional layer ( 32 ) consists of at least one transparent, electrically conductive material. Multilayer film according to one of Claims 8 to 12, characterized in that the additional layer ( 32 ) consists of at least one metallic material. Multilayer body according to one of the claims 8 to 13, characterized in that the contact electrodes and the additional layer consist of a different material and / or their layer thicknesses sometimes differ by more than 90%. Multilayer body ( 30 . 40 ) according to one of claims 8 to 14, characterized in that the additional layer ( 32 ) the carrier foil ( 31 ) completely covered. Multilayer film ( 30 '' . 40 '' ) according to one of claims 8 to 15, characterized in that the additional layer ( 32 ) is formed at least partially in the form of a grid, which consists of a plurality of intersecting grid line formed from the electrically conductive material. Multilayer film ( 30 '' . 40 '' ) according to claim 16, characterized in that the grid is a regular grid with a periodic sequence of grid lines in a first and a second direction. Multilayer film ( 30 '' . 40 '' ) according to claim 17, characterized in that the first direction is at an angle between 80 ° and 100 ° to the contact electrodes ( 33 . 41 ) occupies. Multilayer film according to one of Claims 8 to 18, characterized in that the additional layer ( 32 ) is formed at least partially in the form of a plurality of line-shaped areas, which may also be curved. Multilayer film according to claim 19, characterized in that that the line-shaped areas make an angle between Include 45 ° and 135 ° with the contact electrodes, preferably enclose a right angle with the contact electrodes. Multilayer film according to claim 19 or 20, characterized characterized in that the line-shaped areas are over extend the entire width of the carrier film. Multilayer film according to one of Claims 19 to 21, characterized in that the linear Regions are arranged substantially parallel to each other. Multilayer film according to one of claims 16 to 22, characterized in that in an outdoor area ( 63 ) of the multilayer film, the width of the grid lines or line-shaped regions is higher than in an inner region of the multilayer film and / or in an outer region ( 63 ) of the multilayer film, the line spacing of the grid lines or the line-shaped regions is smaller than in an inner region of the multilayer film, preferably more than twice as high or twice as low. Multilayer film according to one of Claims 16 to 22, characterized in that in an area which the Boundary line between the area covered by the multilayer film the photovoltaic conversion layer and the conversion layer superior Area of the photovoltaic conversion layer on both sides at least 1 mm, preferably surmounted between 1 mm and 3 mm, the width the grid lines or the linear areas higher is considered to be in one area of the laminating film and / or the line spacing the grid lines or the linear areas lower is as in an inner region of the multilayer film, preferably is more than twice as high or twice as low. Multilayer film according to one of claims 8 to 24, characterized in that in the carrier film ( 31 ) or in at least one replication lacquer layer of the multilayer film has a surface structure ( 81 ) is molded. Multilayer film according to Claim 25, characterized that the surface structure in the area of the contact electrodes is shaped and incident in the area of the contact electrodes Deflects light. Multilayer film according to claim 25 or claim 26, characterized in that the surface structure a blaze grating, a lenticular structure or a diffractive structure, in particular a kinoform. Photovoltaic cell according to one of the claims 1 to 7, wherein the multilayer film of the photovoltaic cell after one of claims 8 to 27 is formed.