PHOTOVOLTAIC MODULE WITH INTEGRATED CONNECTIONS FOR SERIES AND PARALLEL ASSEMBLY

Abstract

A photovoltaic module (10) with integrated series and parallel connections comprises a substrate (1) and a plurality of identical photovoltaic cells (2) carried together on one face of the substrate, each photovoltaic cell being formed by a respective portion of the same stack of solid material layers. The photovoltaic module further comprises portions of electrically conductive layers carried by the substrate (1) and arranged to electrically connect the photovoltaic cells (2) in a combination of at least one parallel connection and at least one series connection. Such a photovoltaic module is particularly suitable for use in a tandem-operating composite photovoltaic panel. (Shorthand figure: Figure 2)

Description

Title of the invention: PHOTOVOLTAIC MODULE WITH INTEGRATED CONNECTIONS FOR SERIES AND PARALLEL ASSEMBLY Technical field

[0001] The present description relates to a photovoltaic module with integrated connections for series and parallel assembly, a method of manufacturing such a module and a composite photovoltaic panel operating in tandem which comprises such a module. Prior art

[0002] In order to obtain high electrical output voltages, it is known to produce photovoltaic panels which are each constituted by a series assembly of individual photovoltaic cells. This is the case in particular for photovoltaic panels with commercially available silicon-based cells, the output electrical voltages of which are of the order of a few tens of volts.

[0003] It is also known to produce a series assembly of multiple photovoltaic cells in a way that is integrated into a module. For this, a photovoltaic stack is deposited on a substrate of the module, in the form of a succession of thin layers, including in particular a lower electrode layer, a photoactive portion of the stack and an upper electrode. The material deposition steps are combined with etching steps so that overlaps between upper and lower electrode portions produce the electrical series assembly of separate photovoltaic cells, all formed from the photovoltaic stack that is deposited once on the substrate. The sequence of etchings is commonly referred to as PI etching, which cuts the lower electrode layer, P2 etching, which cuts the photoactive portion of the stack, and P3 etching, which cuts the upper electrode layer.

[0004] Finally, it is also known to produce composite photovoltaic panels operating in tandem, to increase photovoltaic conversion efficiency in a part with lower wavelength values ​​of the spectral radiation absorption domain. Such composite panels thus have higher electricity production capacities. But it is then necessary to adapt between two elementary photovoltaic panels which together constitute the composite panel operating in tandem, their respective dimensions so that they can be superimposed in a common peripheral frame of the composite panel. In addition, it is necessary that the two elementary photovoltaic panels have respective output voltage values ​​when they receive radiation, which are equal or substantially equal to connect them electrically in parallel within the composite panel. Such composite panels with parallel electrical assembly are called four-terminal in the specialist literature, as opposed to composite panels with series electrical assembly, called two-terminal. But when one of the two elementary photovoltaic panels is of a perovskite-based type, a series assembly only of the cells of this panel results in an output voltage value which can be very high, in particular compared to a silicon-based type panel, which prevents the two elementary panels from being connected in parallel. Technical problem

[0005] From this situation, an object of the present invention is to provide low-cost photovoltaic modules whose output voltage value can be easily adjusted by the module design.

[0006] Another object of the invention is to provide such photovoltaic modules which can have large dimensions.

[0007] Finally, yet another aim of the invention is to provide photovoltaic panels tandem-operating composites that are easy to assemble mechanically and electrically, and have low cost prices. Summary of the invention

[0008] To achieve at least one of these aims or another, a first aspect of the invention proposes a photovoltaic module with integrated connections for assembly in series and in parallel. This module comprises a substrate and a plurality of photovoltaic cells which are identical and carried together by one face of the substrate, each photovoltaic cell being formed by a respective portion of the same stack of layers of solid materials which are superimposed on the face of the substrate. This stack comprises at least one lower electrode layer, an upper electrode layer and a photoactive stacking part which is adapted to generate photovoltaic current from radiation incident on this photoactive stacking part.In the stack, the photoactive portion of the stack is intermediate between the bottom electrode layer and the top electrode layer, with the bottom electrode layer being closer to the substrate than the top electrode layer.

[0009] The photoactive portion of the stack varies depending on the type of photovoltaic cells. In particular, it may be a layer of a perovskite-type material which is inserted between an electron transport layer and a hole transport layer.

[0010] In the module of the invention, the photovoltaic cells are juxtaposed on the face of the substrate so as to form parallel lines, with an interline space which separates the photovoltaic cells belonging to two neighboring lines.

[0011] According to the invention, the photovoltaic module further comprises portions of electrically conductive layers, which are also carried by the substrate and arranged to electrically connect the photovoltaic cells to each other according to a mixed electrical assembly which is a combination of at least one parallel assembly of photovoltaic cells or groups of photovoltaic cells with at least one series assembly of photovoltaic cells or groups of photovoltaic cells.

[0012] Thus, the photovoltaic module of the invention combines the two electrical assembly modes in parallel and in series, to adjust the value of the output electrical voltage of the module. Thanks to this combination of the two electrical assembly modes, the value of the output electrical voltage of the module can be selected more freely, in particular to correspond to that of another photovoltaic panel in order to constitute a composite panel operating in tandem.

[0013] In addition, since the electrical assembly of the photovoltaic cells is carried out by portions of conductive layers which are integrated into the module, no electrical connection installation operation needs to be carried out for each photovoltaic cell of the module. The photovoltaic module can thus be manufactured more quickly and less expensively.

[0014] Finally, the photovoltaic module of the invention can have any dimensions, in particular by increasing the number of photovoltaic cells which are connected in parallel. By thus adapting its dimensions to those of another photovoltaic panel, the module of the invention can be easily assembled with this other photovoltaic panel in a common peripheral frame to constitute a composite panel operating in tandem.

[0015] Preferably, some of the portions of electrically conductive layers may be arranged to electrically connect in parallel the photovoltaic cells which belong to the same row, so as to constitute a distinct group of photovoltaic cells assembled in parallel for each row. Some other portions of electrically conductive layers may be arranged to electrically connect in series these groups of photovoltaic cells which correspond respectively to the rows. The value of the output electrical voltage of the photovoltaic module is thus determined by the number of rows in the module, and that of the output electrical current of the photovoltaic module is determined by the number of cells in each row.

[0016] Advantageously, the photovoltaic cells and the layer portions electrically conductive which electrically connect them with each other in the photovoltaic module, may constitute an elementary pattern which is repeated between at least two of the photovoltaic cells within each row, and which is also repeated between at least two of the rows of the photovoltaic module.

[0017] In particular, within each row, the portions of conductive layers which electrically connect in parallel the photovoltaic cells of this row, may be constituted by continuous extensions of the lower electrode layer between the photovoltaic cells of this row. In addition, between two neighboring rows which are called row n and row n+1 respectively, the portions of electrically conductive layers which electrically connect in series the respective groups of cells of the two rows may be constituted by conductive segments which electrically connect the upper electrode layer in row n+1 to the lower electrode layer in row n, through the inter-row space which separates row n and row n+1, and by crossing a height difference above the face of the substrate which corresponds at least to a thickness of the photoactive portion of the stack.Such a design of the pattern inside the module is optimized to reduce areas of the substrate not useful for the photovoltaic conversion of radiation, commonly called dead zones, n can be an integer index of numbering of the lines inside the photovoltaic module, between two opposite edges of the substrate parallel to the lines.

[0018] Furthermore, each conductive segment that electrically connects the upper electrode layer in line n+1 to the lower electrode layer in line n, can extend over one of the continuous extensions of the lower electrode layer in line n, between two neighboring photovoltaic cells of this line n, being in electrical contact with the continuous extension of the lower electrode layer in line n. The dead zones in the photovoltaic module can thus be reduced to a further extent.

[0019] In first embodiments of the invention, each conductive segment that electrically connects the upper electrode layer in line n+1 to the lower electrode layer in line n, may be constituted by an extension of this upper electrode layer. Such a configuration is particularly suitable when the upper electrode layer is metallic or made of a metal alloy, and in particular when it is opaque. The photovoltaic module is then opaque and intended to receive the radiation through the substrate. In this case, the substrate and the lower electrode layer are transparent to the radiation. Such first embodiments can be manufactured with a number of steps that is minimal.

[0020] In second embodiments of the invention, the lower electrode layer and the upper electrode layer may each be transparent to the radiation, in addition to the substrate which is also transparent. In this other case, each conductive segment which electrically connects the upper electrode layer in line n+1 to the lower electrode layer in line n, can be constituted by a superposition of an extension of the upper electrode layer with a segment of a metal or a metal alloy. The segment of metal or metal alloy then extends on one side over the upper electrode layer in line n+1 while being in electrical contact with it, and the superposition of the extension of the upper electrode layer with the segment of metal or metal alloy extends on the other side over one of the continuous extensions of the lower electrode layer in line n, between two neighboring photovoltaic cells of this line n, while being in electrical contact with this lower electrode layer.Such second embodiments may be partially transparent, and adapted to provide a module for incorporation into a tandem-operating composite photovoltaic panel.

[0021] When the photovoltaic cells and the electrically conductive layer portions that connect them together constitute a repeated pattern, the photovoltaic cells that belong to row n+1 may be offset parallel to the rows relative to the photovoltaic cells that belong to row n. Path lengths of photoelectric charges that are generated during use of the photovoltaic module may thus be shorter in the lower and upper electrode layers, so that an internal electrical resistance of the module is reduced. Preferably, the offset length may be equal to half a pitch of the photovoltaic cells in each row, measured parallel to the rows. The internal resistance of the photovoltaic module may thus be reduced in an optimized manner.

[0022] The invention can be particularly applied to a photovoltaic module in which the photoactive stacking part comprises a layer of a perovskite type material. In this case, a width dimension of each photovoltaic cell can be between 5 mm (millimeter) and 50 mm, measured parallel to the lines.

[0023] Generally for the invention, the number of rows in the photovoltaic module and the number of photovoltaic cells in each row may be any. For example, the number of rows in the photovoltaic module may be between 2 and 100, preferably greater than 10, and the number of photovoltaic cells in each row may be between 2 and 200, preferably also greater than 10.

[0024] A second aspect of the invention provides a method for manufacturing a photovoltaic module with integrated connections for series and parallel assembly, which comprises the following steps: / 1 / depositing a lower electrode layer on one face of a substrate, continuously covering this face of the substrate; / 2 / etching first lines in the lower electrode layer, so as to form lower electrode strips separated and parallel to a line direction; / 3 / depositing a photoactive stacking part which is adapted to generate photovoltaic current from radiation incident thereon, by continuously covering the lower electrode strips; / 4 / above each lower electrode strip, etch second lines in the photoactive part of the stack, so as to uncover the lower electrode strip in each second line; / 5 / depositing an upper electrode layer, continuously covering the photoactive stacking portion and the second lines, so that the upper electrode layer is in contact with the lower electrode layer in each second line; then / 6 / etch the upper electrode layer by forming third lines, so as to separate portions of this upper electrode layer which are located on either side of each third line.

[0025] According to the invention, each second line is perpendicular to the line direction and intermediate between two neighboring first lines. In addition, each third line is associated with one of the first lines by comprising third line longitudinal segments which are aligned and parallel to this first line, and which are connected between successive third line longitudinal segments by transverse bypass meanders each arranged to bypass one of the second lines, on the same side of the first line as an offset of the third line longitudinal segments relative to the first line, perpendicular to the line direction and in projection onto the face of the substrate.

[0026] Depending on the embodiment, in particular depending on whether the photovoltaic module is semi-transparent or not, the manufacturing method may further comprise the following step: / 7 / the upper electrode layer being made of a transparent conductive oxide, depositing metal segments on this upper electrode layer, each metal segment being perpendicular to the line direction and extending on one side above one of the second lines inside a meander bypassing this second line by one of the third lines, and extending on the other side above a photovoltaic cell passing continuously above the first line with which the third line is associated.

[0027] In this method, steps / 2 / , / 4 / , / 6 / and / 7 / where appropriate, may be performed using suitable etching patterns to produce a photovoltaic module which is in accordance with the first aspect of the invention, including its improvements and preferred embodiments.

[0028] Finally, a third aspect of the invention relates to a composite photovoltaic panel operating in tandem, which comprises a panel of silicon-based photovoltaic cells, and a semi-transparent additional photovoltaic panel. The additional photovoltaic panel comprises at least one photovoltaic module which is in accordance with the first aspect of the invention. The panel of silicon-based photovoltaic cells and the additional photovoltaic panel are superimposed along a direction of propagation of radiation which is intended to produce electricity during use of the composite photovoltaic panel, the panel of silicon-based photovoltaic cells being located so as to receive the radiation after this radiation has passed through the additional photovoltaic panel. Brief description of the figures

[0029] The characteristics and advantages of the present invention will appear more clearly in the detailed description below of non-limiting exemplary embodiments, with reference to the appended figures among which:

[0030] [Fig. 1] is a sectional view of a stack that can be used in a photovoltaic module that is in accordance with the invention;

[0031] [Fig.2] is a perspective view of the principle of a photovoltaic module which is in accordance with the invention;

[0032] [Fig.3] is a diagram showing photoelectric current collection directions that are effective in the photovoltaic module of [Fig.2];

[0033] [Fig.4a] illustrates a step of a method of manufacturing a photovoltaic module according to the invention;

[0034] [Fig.4b] illustrates another step of the photovoltaic module manufacturing process of [Fig.4a];

[0035] [Fig.4c] illustrates yet another step of the photovoltaic module manufacturing process of [Fig.4a] and [Fig.4b];

[0036] [Fig.4d] is a first sectional view of a photovoltaic module according to the invention and as obtained by the manufacturing method of [Fig.4a]-[Fig.4c];

[0037] [Fig.4e] is a second sectional view of the photovoltaic module of [Fig.4d];

[0038] [Fig.5] corresponds to [Fig.2] for another photovoltaic module which is also in accordance with the invention; and

[0039] [Fig.6] illustrates a composite photovoltaic panel operating in tandem, which uses a photovoltaic module according to [Fig.5]. Detailed description of the invention

[0040] For the sake of clarity, the dimensions of the elements shown in these figures do not correspond to actual dimensions or to actual dimensional ratios. Furthermore, identical references indicated in different figures designate identical elements or elements which have identical functions.

[0041] By way of illustration but without limitation of the invention, the embodiments which are described below are all based on a perovskite type material, as a radiation absorber. The stack which constitutes the photovoltaic cells of the modules described is shown in [Fig.l]. This stack is deposited in successive thin layers on a substrate 1. This substrate 1 can be made of a glass which is transparent to solar radiation. In order from the substrate 1, the stack comprises: - a lower electrode layer 11, which may be made of a transparent conductive oxide such as fluorine-doped tin oxide (SnO2:F), tin-doped indium oxide (ITO), aluminum-doped zinc oxide (AZO or ZnO:Al) or indium-doped zinc oxide (IZO or ZnO:In); - an electron transport layer 131, denoted ETL and which may be based on tin oxide (SnO2), titanium oxide (TiO2), phenyl-C61-butyric acid methyl ester (PCBM), fullerene (C60) or a mixture of at least two of these materials; - a layer of perovskite 132 type material, denoted PKT; - a hole transport layer 133, denoted HTL and which can be based on 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirodifluorene commonly designated spiro-OMeTAD, poly(triaryl amine) commonly designated PTAA, nickel oxide (NiO) or copper thiocyanate (CuSCN); and - an upper electrode layer 12, which may be made of gold (Au), silver (Ag), aluminum (Al), etc. or a metal alloy, or a transparent conductive oxide similar to those mentioned above for the lower electrode layer 11. For each of these layers, the person skilled in the art knows how to select an appropriate composition, an appropriate thickness value, as well as an appropriate deposition method. The electron transport layer 131, that of the perovskite material 132 and that of the hole transport 133 together constitute the photoactive part of the stack, which produces the photovoltaic effect. This photoactive part of the stack is designated by the reference 13 in the following. For the positions of the layers 131 and 133 which have just been cited, the lower electrode layer 11 constitutes the negative electrical terminal of each photovoltaic cell, and the upper electrode layer 12 constitutes its positive electrical terminal. Possibly, the positions of the negative and positive electrical terminals can be reversed, by exchanging the positions of the transport layers 131 and 133 in the stack. Possibly also, the stack which constitutes the photovoltaic cells may include additional layers not shown, but known to those skilled in the art.

[0042] As shown by [Fig. 2], in a photovoltaic module according to the invention which is designated overall by the reference 10, each photovoltaic cell 2 is individually constituted by a respective portion of the stack which has just been described. All the photovoltaic cells 2 are identical in the module 10, or are identical with the possible exception of cells which are located on peripheral edges of the module. The stack portions which constitute the cells 2 are preferably rectangular in projection in a plane parallel to the substrate 1, and arranged in lines which extend parallel to the line direction L. DW designates the width dimension of each photovoltaic cell 2 which is thus formed, measured parallel to the line direction L. For example, DW may be equal to 20 mm.Furthermore, the cells of two neighboring rows are preferably offset by half the pitch of the cells in each row, parallel to the row direction L. The length dimension of each cell 2, denoted DL and measured perpendicular to the row direction L, may be equal to 40 mm, for example.

[0043] The module 10 may comprise, for example, 50 rows and 50 cells 2 per row. The rows may be counted from an edge of the module 10 which is parallel to the row direction L, using an integer counting index denoted n. [Fig.2] thus shows the nth and n+1th rows, called row n and row n+1 in the general part of the present description, and denoted Ln and Ln+i, respectively. For the sake of clarity, [Fig.2] represents a module 10 which comprises only three rows, and only four cells 2 are represented in each row. In the following, N denotes the number of rows in the photovoltaic module 10.

[0044] Etching lines PI separate strips of the lower electrode layer 11 which are separately dedicated to two neighboring rows of cells 2. These etching lines PI are located at an interline space IL which separates the portions of the photoactive stacking part 13 which belong to the two neighboring rows. Each etching line PI may have an individual width of approximately 25 μm (micrometer) to 50 μm. Advantageously, two etching lines PI may be located at each interline space IL, one of which is slightly set back inside one of the rows of cells, to avoid a short circuit in the series assembly of the groups of cells 2 which correspond to two neighboring rows of cells. Thus, all the cells 2 of the same row share the same strip of the lower electrode layer 11.Portions of this lower electrode strip are therefore located under the portions of the photoactive stacking part 13 of the cells 2 of the row concerned, and are continuously connected between neighboring cells within this row. Thus, continuous extensions of each lower electrode strip between cells 2 which are. neighbors within the line, designated by the reference 31 in [Fig. 2], are portions of conductive layer which form part of an electrical assembly in parallel of the cells 2 of the line. Within each line of cells 2, the separation between the portions of photoactive stack part 13 which are relative to neighboring cells 2, is achieved by etching lines P2. These etching lines P2, which may have an individual width of approximately 50 μm measured parallel to the line direction L, leave intact the underlying lower electrode layer strip 11. Finally, the portion of upper electrode layer 12 which belongs individually to each cell 2 covers the portion of photoactive stack part 13 of this cell without coming into contact with the lower electrode layer 11 on the periphery of the portion of photoactive stack part. As can be seen in [Fig.2], each portion of upper electrode layer 12 which belongs to one of the cells 2 of the line Ln+i further extends in the form of a segment 32 between two cells 2 of the line Ln, without however reaching the interline space IL which separates the line Ln from the line Ln.i. This segment 32 continuously crosses the thickness edge of the portion of photoactive stacking part 13 of the cell 2 of the line Ln+i, and crosses the interline space IL which separates the cells 2 of the line Ln+i from those of the line Ln. All segments 32 which thus originate from line Ln+i are in direct electrical contact with the lower electrode strip of line Ln, completing the parallel electrical assembly of cells 2 of line Ln+i and simultaneously carrying out the series electrical assembly of all cells 2 of line Ln+i with all cells 2 of line Ln.Each segment 32 may have a width of about 0.2 mm, or 200 μm, measured parallel to the line direction L, possibly extending above the photoactive stack portion 13 of the neighboring cells 2 (see [Fig. 4d] below). The cells 2 of each line thus constitute a group within which they are all electrically assembled in parallel to each other, and the groups of cells thus formed are electrically assembled in series within the module 10. The portions of the upper electrode layer 12 that belong to the cells 2 of the line Li all extend to a continuous strip 30 of the upper electrode layer 12, which constitutes the positive electrical output terminal of the module 10.Furthermore, the upper electrode layer 12 may be cut into a comb structure at the last row LN of cells 2, opposite the row LB with the teeth of the comb extending as segments 32 on the extensions of the lower electrode layer 11 between the cells 2 of the row LN. This upper electrode layer comb 12, designated by the reference 35, constitutes the negative electrical output terminal of the module 10.

[0045] [Fig.3] shows the circulation paths of the photoelectric charges which are generated in a module 10 according to [Fig.2], when this module receives solar radiation. The electrons which are produced in the photoactive stacking part 13 of each cell 2 of the line Ln are collected by the lower electrode portion 11 of this cell and then circulate in the lower electrode strip of the line Ln parallel to the line direction L, up to the nearest segment 32, according to the arrows Fei. They then circulate in the segments 32 in the direction of the line Ln+i according to the arrows Fe2. Simultaneously, the holes which are produced in the photoactive stacking part 13 of each cell 2 of the line Ln+i are collected by the upper electrode portion 12 of this cell and then transmitted in the direction of the line Ln by the segment 32 which comes from this cell, according to the arrows Ft.These Ft arrows relay the Fe2 arrows in segments 32 because the Ft and Fe2 arrows relate to photoelectric charges of opposite signs.

[0046] We now describe successive steps of a method for manufacturing a module 10 which is in accordance with the principle illustrated by [Fig. 2]. In an initial step, the lower electrode layer 11 is deposited on the substrate 1, so as to uniformly cover one face of the latter. Then a first etching step is implemented, to produce the etching lines PL. The material of the lower electrode layer 11 is entirely removed in each of the etching lines PI, so as to electrically insulate the strips of lower electrode layer 11 which will correspond to successive lines Ln and Ln+[ of cells 2. The etching lines PI are produced continuously across the entire module 10 during manufacture, parallel to the line direction L as shown in [Fig. 4a].Possibly but optionally, two PI etching lines can be made at each interline space IL, to further prevent, in the finished module 10, the lower electrode strip 11 of the Ln line of cells 2 from being in contact with the portions of the photoactive stacking part 13 of the Ln+i line.

[0047] The photoactive stacking part 13 is then deposited on the module 10 during manufacture, so as to uniformly cover the latter. A second etching step is then implemented, to produce the etching lines P2. The material of the photoactive stacking part 13 is entirely removed in each of the etching lines P2, to expose the lower electrode layer 11 inside these etching lines P2. The etching lines P2 are produced perpendicular to the line direction L inside each future line of cells 2, as shown in [Fig.4b].

[0048] The upper electrode layer 12 is then deposited on the module 10 during manufacture, again so as to cover it continuously. A third etching step is then implemented, to separate the portions of upper electrode layer 12 of cells 2 which are neighbors within each line, while leaving the segments 32 in the etching lines P2. This third etching step also removes the upper electrode layer 12 in longitudinal line segments P3L which are parallel to the line direction L, near the interline spaces IL between two successive segments 32. An etching pattern which is possible for this third etching step is shown in [Fig.4c] and designated P3. Each etching line P3 thus comprises a transverse contour meander P3C between two longitudinal line segments P3L which are successive along the line direction L, to contour one of the etching lines P2.

[0049] [Fig.4d] and [Fig.4e] are sections of a module 10 according to the invention and as obtained by the method which has just been described. Its electrical operation is identical to that which has been described above with reference to [Fig.2] and [Fig.3] despite the topographical differences which appear between [Fig.2] on the one hand and [Fig.4d]-[Fig.4e] on the other hand, taking into account the very short electrical conduction lengths of the materials of the layers 131, 132 and 133. The section plane of [Fig.4d] is parallel to the line direction L and shows the separation between two cells 2 of the same line Ln. The section plane of [Fig.4e] is perpendicular to the line direction L and shows an interline space IL at the separation between two neighboring lines of cells 2.

[0050] The material deposition methods which are used respectively for the lower electrode layer 11, each layer of the photoactive stacking part 13 and then for the upper electrode layer 12 may each be one of those known to those skilled in the art for the material concerned.

[0051] In the embodiment described above, the upper electrode layer 12 is made of metal or a metal alloy, and because of this the module 10 is opaque. From an illumination of the module 10 through its substrate 1 which is transparent, this metal layer produces a mirror function on the rear face, thanks to which the part of the radiation which was not absorbed during its passage through the photoactive stacking part 13, passes through this part 13 a second time. However, the module 10 can be transparent in alternative embodiments of the invention. For this, the manufacturing method which has just been described can be repeated up to the deposition of the upper electrode layer 12, but a transparent conductive oxide is now used for this layer 12, for example the same material as that of the lower electrode layer 11, replacing the metal or the metal alloy.The etching patterns PI, P2 and P3 remain identical. In this case of a transparent module, the manufacturing process is completed by forming, on the module 10, metal segments 33 which are perpendicular to the line direction L, which pass through each cell 2 and extend onto the neighboring line of cells in superposition with the segments 32. Each metal segment 33. may also have a width of about 0.1 mm to 0.2 mm, measured parallel to the line direction L. The metal segments 33, associated with the underlying segments 32 of the upper electrode layer 12 made of transparent conductive oxide, achieve the electrical assembly in series of the separate groups of cells which correspond respectively to neighboring lines, while occupying a very small fraction of the surface of the module 10. The metal segments 33 ensure that these electrical assembly connections in series have an electrical conduction which is sufficiently high, much higher than that of the only segments 32 made of transparent conductive oxide. These metal segments 33 are shown in broken lines in [Fig.4d] and [Fig.4e], considering that the upper electrode layer 12 is then made of transparent conductive oxide. [Fig.5] corresponds to [Fig.2] for an embodiment where the module 10 is thus transparent.It shows each segment 32, now made of transparent conductive oxide, which is covered by a metal segment 33. .

[0052] Finally, [Fig.6] shows a possible use of a module 10 which is in accordance with the principle of [Fig.5], to constitute a composite photovoltaic panel operating in tandem. The composite photovoltaic panel is designated overall by the reference 100. It comprises a photovoltaic panel with silicon-based cells 20, which is arranged parallel to another panel which is constituted by the module 10 of [Fig.5]. For this reason, the reference 10 is used in [Fig.6] to designate the panel which is constituted by the module of [Fig.5]. The panel 20 may be of a commercially available model. In particular, it may be constituted by a set of silicon-based cells which are produced on separate square substrates, arranged in a paving pattern inside this panel 20, and connected by wires or metal tracks according to an electrical assembly in series and / or in parallel.The two panels 10 and 20 have identical dimensions, for example of the order of 1 m (meter) by 2 m. They can thus be kept parallel to each other by a common peripheral frame 30, which encloses the edge of each panel 10, 20. Preferably, the panel 10 can be oriented so that the face of its substrate 1 which carries the photovoltaic stack is turned towards the panel 20, and the panel 20 has its photoactive face turned towards the panel 10. Thus, solar radiation R which is incident on the side of the panel 10 is partially absorbed by the latter and partially transmitted towards the panel 20, which produces additional absorption. The absorption of a portion of the radiation R by each of the photovoltaic panels 10 and 20 provides a corresponding quantity of electricity, but each panel 10, 20 absorbs in a portion of the spectrum of the radiation R which is different from that of the other panel.More specifically, the panel 10 absorbs a portion of the radiation R which has lower wavelength values ​​than the additional portion of the radiation R which is absorbed by the panel 20. This func- . Operation of the composite panel 100 is commonly referred to as tandem operation. Advantageously, the panel 10 has a number of lines such that the output electrical voltages of the two panels 10 and 20 are substantially identical. In this way, the two panels 10 and 20 can be connected in parallel with each other, so that their respective output electrical currents add together.

[0053] It is understood that the invention can be reproduced by modifying secondary aspects of the embodiments which have been described in detail above, while retaining at least some of the advantages cited. In particular, the photovoltaic cells of the module of the invention can be alternatively based on a silicon junction, or based on a type III / V junction, such as of the GalnP (gallium-indium-phosphorus) type, or be of the CdTe (cadmium telluride) or CIGS (copper, indium and gallium selenide) type. Finally, all the numerical values ​​which have been cited have been cited only for illustration purposes, and can be changed depending on the application considered.

Claims

Claims

1. Photovoltaic module (10) with integrated connections for assembly in series and in parallel, comprising a substrate (1) and a plurality of photovoltaic cells (2) which are identical and carried together by one face of the substrate, each photovoltaic cell being formed by a respective portion of the same stack of layers of solid materials which are superimposed on the face of the substrate, said stack comprising at least one lower electrode layer (11), one upper electrode layer (12) and a photoactive stack portion (13) which is adapted to generate photovoltaic current from radiation incident on said photoactive stack portion, the photoactive stack portion being intermediate between the lower electrode layer and the upper electrode layer in the stack, and the lower electrode layer being closer to the substrate than the upper electrode layer,the photovoltaic cells (2) being juxtaposed on the face of the substrate (1) so as to form parallel lines (Ln, Ln+i), with an interline space (IL) which separates the photovoltaic cells belonging to two neighboring lines, characterized in that the photovoltaic module (10) further comprises portions of electrically conductive layers, which are also carried by the substrate (1) and arranged to electrically connect the photovoltaic cells (2) with each other according to a mixed electrical assembly which is a combination of at least one parallel assembly of photovoltaic cells or groups of photovoltaic cells with at least one series assembly of photovoltaic cells or groups of photovoltaic cells.,

2. Photovoltaic module (10) according to claim 1, in which some of the portions of electrically conductive layers are arranged to electrically connect in parallel the photovoltaic cells (2) which belong to the same line (Ln, Ln+i), so as to constitute a distinct group of photovoltaic cells assembled in parallel for each line, and other portions of electrically conductive layers are arranged to electrically connect in series said groups of photovoltaic cells which correspond respectively to the lines.

3. A photovoltaic module (10) according to claim 1 or 2, wherein the photovoltaic cells (2) and the portions of electrically conductive layers which electrically connect said photovoltaic cells with each other in the photovoltaic module, constitute an elementary pattern which is repeated between at least two of the photovoltaic cells within each row (Ln, Ln+i), and which is also repeated between at least two of the rows of the photovoltaic module.

4. Photovoltaic module (10) according to claims 2 and 3, wherein: within each row (Ln, Ln+i), the portions of electrically conductive layers which electrically connect in parallel the photovoltaic cells (2) of said row, are constituted by continuous extensions (31) of the lower electrode layer (11) between the photovoltaic cells of said row, and between two neighboring rows (Ln, Ln+i) called row n and row n+1 respectively, the portions of electrically conductive layers which electrically connect in series the respective groups of cells of the two rows are constituted by conductive segments which electrically connect the upper electrode layer (12) in row n+1 to the lower electrode layer (11) in row n, through the inter-row space (IL) which separates row n and row n+1,and by crossing a height gap above the face of the substrate (1) which corresponds at least to a thickness of the photoactive stacking part (13).,

5. Photovoltaic module (10) according to claim 4, wherein each conductive segment which electrically connects the upper electrode layer (12) in line n+1 to the lower electrode layer (11) in line n, extends over one of the continuous extensions (31) of the lower electrode layer in line n, between two neighboring photovoltaic cells (2) of said line n, being in electrical contact with said continuous extension of the lower electrode layer in line n.

6. A photovoltaic module (10) according to claim 5, wherein each conductive segment that electrically connects the upper electrode layer (12) in line n+1 to the lower electrode layer (11) in line n, is constituted by an extension (32) of said upper electrode layer, or wherein the lower electrode layer (11) and the upper electrode layer (12) are each transparent to radiation, and each conductive segment that electrically connects the upper electrode layer in line n+1 to the electrode layer lower in line n, is constituted by a superposition of an extension (32) of said upper electrode layer with a segment (33) of a metal or a metal alloy, said segment of metal or metal alloy extending on one side on the upper electrode layer in line n+1 while being in electrical contact with said upper electrode layer, and the superposition of the extension of said upper electrode layer with the segment of metal or metal alloy extending on the other side on one of the continuous extensions (31) of the lower electrode layer in line n, between two photovoltaic cells (2) adjacent to said line n, while being in electrical contact with said lower electrode layer.

7. Photovoltaic module (10) according to one of claims 3 to 6, wherein the photovoltaic cells (2) which belong to row n+1 are offset parallel to the rows (Ln, Ln+i) relative to the photovoltaic cells which belong to row n, preferably with an offset length which is equal to half a pitch of the photovoltaic cells in each row, measured parallel to the rows.

8. Photovoltaic module (10) according to one of claims 1 to 7, in which the photoactive stacking part (13) comprises a layer of a perovskite-type material.

9. A photovoltaic module (10) according to claim 7 and claim 8, wherein a width dimension (DW) of each photovoltaic cell (2) is between 5 mm and 50 mm, measured parallel to the lines (Ln, Ln+1).

10. A method for manufacturing a photovoltaic module (10) with integrated connections for series and parallel assembly, comprising the following steps: / 1 / depositing a lower electrode layer (11) on one face of a substrate (1), continuously covering said face of the substrate; / 2 / etching first lines (PI) in the lower electrode layer (11), so as to form separate lower electrode strips parallel to a line direction (L); / 3 / depositing a photoactive stacking part (13) which is adapted to generate photovoltaic current from radiation incident on said photoactive stacking part, continuously covering the lower electrode strips; / 4 / above each lower electrode strip, etching second lines (P2) in the photoactive stacking part (13),

11.

12. so as to uncover said lower electrode strip in each second line; / 5 / depositing an upper electrode layer (12), continuously covering the photoactive stacking part (13) and the second lines (P2), so that the upper electrode layer is in contact with the lower electrode layer (11) in each second line; then / 6 / etching the upper electrode layer (12) by forming third lines (P3), so as to separate portions of said upper electrode layer which are located on either side of each third line, the manufacturing method being characterized in that each second line (P2) is perpendicular to the line direction (L) and intermediate between two neighboring first lines (PI), and in that each third line (P3) is associated with one of the first lines (PI) by comprising third line longitudinal segments (P3l) which are aligned and parallel to said first line, and which are connected between successive third line longitudinal segments by transverse bypass meanders (P3C) each arranged to bypass one of the second lines (P2), on the same side of the first line as an offset of the third line longitudinal segments relative to said first line, perpendicular to the line direction (L) and in projection onto the face of the substrate (1), and in that steps / 2 / , / 4 / and / 6 / are carried out using etching patterns adapted to produce a photovoltaic module (10) which is according to one of claims 1 to 9. The method of claim 10, wherein the upper electrode layer (12) is made of a transparent conductive oxide, and the method further comprises the step of: / 7 / depositing metal segments (33) on the upper electrode layer (12), each metal segment being perpendicular to the line direction (L) and extending on one side above one of the second lines (P2) inside a meander bypassing said second line by one of the third lines (P3), and extending on the other side above a photovoltaic cell (2) passing continuously above the first line (PI) with which said third line is associated. Composite photovoltaic panel (100) operating in tandem, comprising a panel (20) of photovoltaic cells which are based of silicon, and a semi-transparent additional panel which comprises at least one photovoltaic module (10) according to one of claims 1 to 9, the silicon-based photovoltaic cell panel and the semi-transparent additional panel being superimposed along a direction of propagation of radiation which is intended to produce electricity during use of the composite photovoltaic panel, the silicon-based photovoltaic cell panel being located so as to receive the radiation after said radiation has passed through the additional photovoltaic panel.

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