EP4133591A1

EP4133591A1 - Miura-ori photovoltaic module

Info

Publication number: EP4133591A1
Application number: EP21718977.8A
Authority: EP
Inventors: Juan Camilo ORTIZ LIZCANO; Olindo ISABELLA; Victor Arturo MARTINEZ LOPEZ; Miroslav Zeman
Original assignee: Technische Universiteit Delft
Current assignee: Technische Universiteit Delft
Priority date: 2020-04-09
Filing date: 2021-04-01
Publication date: 2023-02-15
Also published as: CN115668753B; CN115668753A; WO2021206542A1; NL2025309B1

Abstract

The present invention is in the field of a Miura-Ori Photovoltaic Module, for converting light into electricity, i.e. a module that can easily be unfolded and folded and hence be transported or transferred easily, and a system comprising at least two of such modules and optionally comprising further elements.

Description

Miura-Ori Photovoltaic Module

FIELD OF THE INVENTION

The present invention is in the field of a Miura-Ori Photovoltaic Module, for converting light into electricity, i.e. a module that can easily be unfolded and folded and hence be trans ported or transferred easily, and a system comprising at least two of such modules and optionally comprising further elements.

BACKGROUND OF THE INVENTION

A solar cell, or photovoltaic (PV) cell, is an electrical device that converts energy of light, typically sun light (hence “solar”), directly into electricity by the so-called photovoltaic effect. The solar cell may be considered a photoelectric cell, having electrical characteristics, such as current, voltage, resistance, and fill factor, which vary when exposed to light and which vary from type of cell to type.

Solar cells are described as being photovoltaic irrespective of whether the source is sun light or an artificial light. They may also be used as photo detector.

When a solar cell absorbs light it may generate either electron-hole pairs or excitons. In or der to obtain an electrical current charge carriers of opposite types are separated. The separated charge carriers are “extracted” to an external circuit, typically providing a DC-current. For prac tical use a DC-current may be transformed into an AC-current, e.g. by using a transformer.

Typically, solar cells are grouped into an array of elements. Various elements may form a panel, and various panels may form a system.

Wafer based c-Si solar cells contribute to more than 90% of the total PV market. Accord ing to recent predictions, this trend will remain for the upcoming years towards 2020 and many years beyond. Due to their simplified process, conventional c-Si solar cells dominate a large part of the market. As alternative to the industry to improve the power to cost ratio, the silicon hetero junction approach has become increasingly attractive for PV industry, even though the relatively complicated process to deploy the proper front layers, such as a thermal conductive oxide (TCO) and an inherent low thermal budget of the cells limiting usage of existing production lines and thus result in a negligible market share so far. A heterojunction is the interface that occurs be tween two layers or regions of dissimilar crystalline semiconductors. These semiconducting ma terials have unequal band gaps as opposed to a homojunction. A homojunction relates to a semi conductor interface formed by typically two layers of similar semiconductor material, wherein these semiconductor materials have equal band gaps and typically have a different doping (either in concentration, in type, or both). A common example is a homojunction at the interface be tween an n-type layer and a p-type layer, which is referred to as a p-n junction. In heterojunc tions advanced techniques are used to precisely control a deposition thickness of layers involved and to create a lattice-matched abrupt interface. Three types of heterojunctions can be distin guished, a straddling gap, a staggered gap, and a broken gap.

Recently foldable solar cells have entered the market. These solar cells are typically pro vided in small arrays, having a limited number of cells, such as less then 20 cells. They may be used outdoors, providing basic electrical power, such as to appliances. In an alternative these cells may be unfolded in space.

Tang et al. in Appl. Phys. Lett. 104, 083501 (2014) (https://doi.Org/10.l 063/1.4866145) show principles of fabrication of foldable solar cells. Typically, the solar cells are provided in a single array which cannot be connected in series or in parallel. Therewith power output, voltage, or current is typically limited.

WO 2016/070225 Al recites a portable photovoltaic unit and a photovoltaic system. The system comprises a plurality of interconnectable photovoltaic module units each unit comprising a photovoltaic device. The units are arranged for releasably coupling to each other so that an electrical interconnection between an N-side of a unit and a P-side of the next unit is established and energy can be accessed from electrical contacts that are disposed on the same side of one of the units. In addition at the best a row of PV-units can be made, but not an array of such units. The units are typically non-flexible, whereas joints or contacts between units are flexible. The units themselves appear not to be foldable. Despite the system being portable folding thereof is still relatively cumbersome.

US 2018/323743 Al recites modular photovoltaic (PV) system can include a PV cell, a frame coupled to the PV cell, and a converter. The frame is configured to support a plurality of pairs of externally accessible connectors, each pair having a positive voltage connector and a negative voltage connector, the positive voltage connector of each pair of the plurality electri cally connected to each other and the negative voltage connector of each pair of the plurality electrically connected to each other. The converter is configured to receive voltage from the PV cell and change the voltage for output at one or more pairs of the externally accessible connect ors. The converter may include Maximum Power Point Tracking services to manage the power output from the PV cell. Multiple PV systems may be connected to each other in coplanar and non-coplanar relationships. In some embodiments, the frames have triangular, rectangular, or other polygonal shapes. The modules are typically non-flexible, whereas joints or contacts be tween units are flexible. The modules themselves appear not to be foldable, as a frame is pro vided.

The present invention relates to an improved foldable solar cell array which overcomes one or more of the above disadvantages, without jeopardizing functionality and advantages.

SUMMARY OF THE INVENTION

The present invention relates in a first aspect to a foldable array of PV-cells accord ing to claims 1, which is lightweight and portable. The present foldable array (10) of PV-cells comprises at least n*m PV-cells electrically connected to one and another, wherein n>2 and m>2, and at least four magnetic array-array connectors (2,3), which may be ejectable or fixed, hence in an retracted configuration or in an ejected configuration, at least two for a positive elec trical array-array contact (2), and at least two for a negative array-array contact (3), wherein at least one positive electrical array-array connector extends in a horizontal direction and wherein at least one positive electrical array-array connector extends in a vertical direction and wherein at least one negative electrical array-array connector extends in a horizontal direction and wherein at least one negative electrical array-array connector extends in a vertical direction, and wherein each connector is electrically insulated, wherein each PV-cell has a geometrical form, wherein the PV-cells are provided on a backside film, wherein the PV-cells are covered with a frontside film, wherein at an edge of each PV-cell at least two adjacent fold lines (8) are provide for up ward movement, and wherein at an edge of each PV-cell at least two adjacent fold lines (9) are provide for downward movement, and wherein the array is adapted to be folded with one single movement such as by comprising a hinge mechanism for fully folding/unfolding. It is slightly preferred to have an odd number of rows, in view of foldability. The foldable array may simply be folded by “pushing” corners inward, and may be unfolded by moving opposite corners away from one and another. In view of folding it is preferred to comprise a hinge mechanism in the foldable module. In view of folding/unfolding it is also preferred to have PV-cells with rather straight (closer to 90 degrees) corners, than to use very acute/sharp corners. Corners between re spectively 70-110 degrees are preferred, such as corners between about 80-about 100 degrees. At every edge of a PV-cells, or likewise block of PV-cells, typically one fold line is present. De pending on a size of PV-cells one may combine a number of PV-cells into sub-cells, as in fig. 2. Therewith a lightweight, portable, and foldable, easily connectable array of PV-cells is provided.

Therewith a new foldable PV module inspired by origami is provided. The PV module is lightweight and can be unfolded and fold with one single movement. Modularity is at the core of the design, as several of these foldable modules can be (interconnected to form a PV array of in principle any layout and size. The flexibility increases a variation in use. This modularity, allows to go from small simple applications to full PV systems with just the addition of PV modules. The invention allows modules to be carried easily in large quantities and be connected as needed. Current foldable modules are either very small with low output power or in need of heavy equip ment for transportation. This solution allows very easy deployment with the use of only one ac tuator. High-efficiency crystalline silicon solar cells can be used, and low weight is ensured by the use of a lightweight encapsulation layer and transparent flexible foil. The backside of the module is made out of a flexible foil, such as a black or white foil. This ensures a very pleasant aesthetic appeal. As mentioned, the module may be provided with an encapsulating layer to fur ther ensure hermeticity and safety of use.

In a second aspect the present invention relates to a system comprising at least two arrays according to the invention. The arrays are electrically connected by magnetic contacts, and there with the connection is secured. The magnetic contacts are not very thick, so that the arrays can still be folded easily and do not occupy much space when folded. The magnetic contacts may be made of a flexible material, such as an electrically conductive tape/adhesive. They may also be incorporated in a layer or layers, protecting them from the environment. Therewith electrical power can be provided, especially under sunny conditions. As the array, or system, may also be oriented towards the sun, preferably perpendicular to sunlight emitted by the sun, the yield can be increased simply by rotating the array or system accordingly. Now and then rotating can be repeated in order to compensate for rotation of the earth.

Thereby the present invention provides a solution to one or more of the above-mentioned problems.

Advantages of the present description are detailed throughout the description. References to the figures are not limiting, and are only intended to guide the person skilled in the art through details of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates in a first aspect to a foldable array of PV-cells, and in a second aspect to a system comprising at least two such arrays.

In an exemplary embodiment of the present foldable array of PV-cells each cell may comprise 2-24 sub-cells 11, such as 4-12 sub-cells.

In an exemplary embodiment of the present foldable array an array provides a maxi mum output of 20-200 W, in particular 30-100W, such as 40-60 W. A lower output may for in stance be used for loading a small electronic device, such as a telephone, and a larger array for loading/supporting a communication system. Such makes the present arrays extremely suited for emergency situations, as a first responder, such as in an emergency situation, in a remote loca tion, or for holiday application.

In an exemplary embodiment of the present foldable array of PV-cells the geometrical form may be selected from rectangles, such as squares, paralepidid, such as diamond. Th geo metrical form and the foldability are typically adapted to one and another.

In an exemplary embodiment of the present foldable array of PV-cells all PV-cells in an array of n*m may be electrically connected in series, such as wherein in a column a positive PV-cell (n=i) terminal is electrically connected 4 to an adjacent negative PV-cell terminal (n=i+l), and wherein a first or last PV-cell (n=n or n=l) terminal of a row (m=j) is electrically connected 4 to an adjacent opposite PV-cell terminal (n=n or n=l, m=j+l), and wherein a first terminal 12 of the first cell (n=l, m=l) is in electrical contact with at least two magnetic array- array connectors 2,3 , and wherein a second terminal 13 of the last cell (n=l or n, m=m) is in electrical contact with at least two magnetic array-array connectors 3,2 of opposite electrical po larity (see e.g. fig. 3 in this respect).

In an exemplary embodiment of the present foldable array of PV-cells in case of m=odd the array (see e.g. fig. 4b in this respect) may comprise at least four magnetic array-array connectors for a positive electrical array-array contact 2 provided at one side of the array (the n=l side), at least two magnetic array-array connectors 2 at a first edge (m=l) at least two mag netic array-array connectors 2 at a second edge (m=m), and an electrical connection 5 between the connectors at the first edge and the connectors at the second edge, and at least four magnetic array-array connectors for a negative electrical array-array contact 3 provided at one side of the array (the n=n side), at least two magnetic array-array connectors 2 at a first edge (m=l) at least two magnetic array-array connectors 2 at a second edge (m=m), and an electrical connection 5 between the connectors at the first edge and the connectors at the second edge, or in case of m=even the array (see e.g. fig. 6b in this respect) may comprise at least two magnetic array-array connectors for a positive electrical array-array contact 2 provided at one side of the array (the n=l side) at a first edge (m=l), and at least two magnetic array-array connectors for a negative electrical array-array contact 3 provided at the same side of the array (the n=l side) at a second edge (m=m).

In an exemplary embodiment of the present foldable array of PV-cells the PV-cells may be selected from conventional homo-junction and heterojunction solar cells, mono-facial and bi-facial solar cells, n-type and p-type mono-crystalline Si, micro-crystalline Si bulk, front contacted solar cells, back contacted solar cells, front and rear junction solar cells, interdigitated back contacted solar cells, and combinations thereof.

In an exemplary embodiment of the present foldable array of PV-cells may have a thickness of 10-100 um.

In an exemplary embodiment of the present foldable array of PV-cells may comprise an anti -reflective coating.

In an exemplary embodiment of the present foldable array of PV-cells the PV-cells may be provided on a polymeric backside film, such as a transparent backside film (which film may also be referred to as a “foil”, typically a polymeric foil, such as an elastomeric foil), wherein the polymer is preferably selected from PE, PET, and PP.

In an exemplary embodiment of the present foldable array of PV-cells the backside film may have a thickness of 10-100 um.

In an exemplary embodiment of the present foldable array of PV-cells the PV-cells comprise a polymeric frontside film, such as a transparent frontside film (which film may also be referred to as a “foil”, typically a polymeric foil, such as an elastomeric foil), wherein the poly mer is preferably selected from PE, PET, and PP.

In an exemplary embodiment of the present foldable array of PV-cells the frontside film may have a thickness of 10-100 um.

In an exemplary embodiment of the present foldable array of PV-cells a third film may be provided on the frontside or backside of the array, or on both.

In an exemplary embodiment of the present foldable array of PV-cells the PV-cells may comprise at least one light-weight encapsulation layer, typically at either side of the PV- cells, such as a transparent elastic polymer layer, such as of Ethylene Vinyl acetate (EVA). En capsulation may be achieved by EVA (Ethylene Vinyl acetate) which is a transparent elastic pol ymer that once is heated up to 150 °C becomes liquid and once is cooled down acts as a glue of the different components of the module. Commercial modules use EVA to glue glass and Tedlar to the solar cells produce the modules, but due to the glass they cannot be flexible. Recently, transparent flexible foils that ensure hermeticity and high light transmittance have become popu lar and is allowing the creation of flexible modules. A thickness of said encapsulation layer may be from 10-100 pm, such as 20-30 pm, each individually. In an exemplary embodiment of the present foldable array of PV-cells array may have a surface area of > 10 cm², and a mass of < 1 gr/cm².

In an exemplary embodiment of the present foldable array of PV-cells the array may be portable.

In an exemplary embodiment the present foldable array of PV-cells may further com prise at least one component selected from a junction box, an electrical connection, a trans former, power electronics, and an electrical power storage unit.

In an exemplary embodiment of the present foldable array of PV-cells folding may be provided by Miura-ori technique.

In an exemplary embodiment of the present foldable array at least one fold line com prises at least one hinge (30), wherein the hinge preferably comprising at least one insulating material (31,33) at an outer side thereof, and wherein the hinge preferably comprises an electri cal connector for connecting a group of cells with an adjacent group of cells. Therewith electrical connection between adjacent groups of PV-cells is secured over time.

In an exemplary embodiment of the present foldable array of PV-cells the magnetic connector may be selected from iron comprising materials.

In an exemplary embodiment of the present foldable array of PV-cells magnetic array- array connectors may be provided at an edge of the array, preferably at the end of an edge.

In an exemplary embodiment of the present foldable array each magnetic connector in dividually is located at a fixed position relative to an array, such as at a side thereof at a fixed distance from a corner of the array, such as at 1-5 cm from the comer.

In an exemplary embodiment of the present foldable array of PV-cells the magnetic connector each individually may have a contact area of 0.5-10 cm², preferably 1-5 cm², such as 3.2+1 cm², and/or a diameter of 2+1.3 cm, and/or a thickness of 1-15 mm, preferably 2-10 mm, such as 7 mm.

In an exemplary embodiment of the present foldable array of PV-cells the magnetic connector may be a magnet to MC4 connector (both +/-) adaptor is provided, such that integra tion of the flexible magnetic modules with commercially available power electronics is properly ensured.

In an exemplary embodiment the present system may comprise an embedded charging station, such as for a mobile phone.

In an exemplary embodiment the present system may comprise power electronics and/or an adaptable junction box.

The invention is further detailed by the accompanying figures and examples, which are exemplary and explanatory of nature and are not limiting the scope of the invention.

To the person skilled in the art it may be clear that many variants, being obvious or not, may be conceivable falling within the scope of protection, defined by the present claims.

SUMMARY OF FIGURES

Figures 1-3, 4a-b, 5, 6a-b,7-l 1 show experimental details of the present invention. DETAILED DESCRIPTION OF FIGURES

10 foldable array of n*m solar cells

1 electrical connection between solar cells

2 positive magnetic connector

3 negative magnetic connector

4 electrical cell-cell connection

5 electrical connection

6 electrical conductor

7 insulator

8 fold line for upward movement

9 fold line for downward movement

11 sub-group of n*m cells

12 first terminal of first cell

13 second terminal of last cell

21 front side film

22 front side encapsulation layer

23 PV-layer

24 back side encapsulation layer

25 back side film

30 reinforcement

31 insulating cover central

32 insulating cover wire

33 connecting rod

34 electrical wire

The figures are further detailed in the description of the experiments below.

Figure la shows a way of folding an array 10 of PV-cells, with valley fold lines 9 and mountain fold lines 8.

Figure lb shows four sub-cells 11.

Figure 2 shows schematics of the present foldable module with a front side film 21, an op tional front side encapsulation layer 22, a PV-layer 23, an optional back side encapsulation layer 24, and a back side film 25.

Figure 3 shows an even variant of an array 10, with 4 columns, each column having 4 cells. In each column a cell is electrically connected to an adjacent cell by connection 4, the + and - indicating the polarity of the respective PV-cell terminal. Columns of cells are either attached at a top side (column 1-2 and column 3-4) or at a bottom side (column 2-3). Therewith a serial con nection of cells is provided. A first positive terminal 2, located at a first cell 12, with magnetic contact, and negative terminal 3, with magnetic contact, located at last cell 13, is shown.

Fig. 4a shows schematically a serial contacted array 10 with only one positive and only one negative magnetic contact indicated. Such an array can not be connected in series or parallel with other similar arrays, at least not without forming a regular patter and layout. Therefore, four neg ative magnetic contacts 3 and four positive magnetic contacts 2 are shown in fig. 4b. For this lay out, the magnetic interconnects can be at opposite ends of the module, and there may be a need of 4 magnets per side. The above is a transparent foil/foil flexible module with the 8 magnetic connectors (exaggerated for better view), and the detail of them can be viewed in fig. 5. The magnetic contacts of either polarity are electrically interconnected by respective electrical con nections 5.

One could consider, for the odd column arrangement, that a similar connector design can be produced to that of the even number of columns of fig. 6b. This would reduce the number of magnetic connectors, and the series-parallel connection remains as simple as the even number case. However, for the Miura-ori design, in that case the required cable across the module for the negative connector can significantly hinder the folding characteristics or, if made by flexible conductive tape, the reliability of the product after some folding/unfolding cycling can be poor. So this construction is less preferred.

Figure 5 shows an enlargement of the magnetic contacts 2,3, each individually surrounded by insulator 7. The idea of these 4 magnetic connectors per side is to eliminate any wiring be tween the modules no matter what interconnection scheme (series or parallel) you want to pro duce. The black line around the module is a flexible frame. Also isolation of the magnetic con nectors may be needed to avoid any accidental short circuit during connection. The connectors may also comprise detachment means, such as springs; one can use springs that can give the magnets the ability to be released by pressing them, the spring will pop the connector out. Series interconnection is done by simple rotation of the module, whereas parallel interconnection is achieved by horizontal arrangement

Fig. 6a shows a layout of an array with even columns, and a way to indicate respective cells by n, ie [1-n], and m, j e [1-m] Fig. 6b shows an example of at least two negative magnetic contacts 3 and two positive magnetic contacts 2, provided at a bottom side, at either right/left side of the array.

Fig. 7 shows an example of forming the present system with m=odd, wherein arrays on the bottom row are rotated 180 degrees; notice the ejected contacts are shown whilst the remaining are retracted. Notice that, thanks to the design of the 4 magnets on the sides and both ends of the panel, many columns and rows can be connected without limitations, it’s just a matter of rotating the panels to face the right polarities. Likewise, fig. 8 shows an example of forming the present system with m=even, wherein arrays on the bottom row are rotated 180 degrees. For the even variant only two rows can be connected. Clearly the odd and even variants may be combined.

The preferred output voltages of the PV panels are preferably sufficient enough so they can be properly used on applications ranging from 5 VDC to 96 VDC. The smallest panel could pro duce around 8 - 10 VDC and the largest around 30 VDC, then series interconnection can ramp up the voltage to be suited with a commercially available MPPT trackers and charge controllers (in case batteries are also used on the system). Currents could range from 2 A (required by most modern devices) to 6 - 10 A for full area cells (5 in and 6 in). Embedded AC conversion is also possible with smart power electronics.

As shown the magnets are electrically connected to the +/- terminals of the PV-modules. The area of the magnets could be around 3.2 cm² (a diameter of around 2 cm with thickness of around 7 mm). The current produced by large area solar cells can be safely handled by magnets of this size.

Fig. 9 shows four panels, comprising a group of PV-cells, forming part of the present fold- able array. In between panels one hinge 30 is provided, of which at the bottom side an example is given, without the further elements of figure 10.

Fig. 10 shows a cross-section of the present hinge 30, which functions as a reinforcement, insulating cover central 31 for electrically isolating the hinge, insulating cover wire 32 for elec trically insulating wire 32, connecting rod 33, and electrical wire 34 for electrically connecting one panel to an adjacent panel. So different panels of the Miura-Ori are connected by hinges.

The hinge design has a connecting rod in its center, covered by an insulating material. The tab bing wire coming from the interconnected cells of a panel is attached (when necessary, not all shingles conduct current) to both ends of the rod. This way one panel is connected to the next to built the Miura-Ori Solar module. Once the tabbing wire is welded to the rod, insulated tape is used to increase safety. The insulating cover consists of two parts to allow the fold and unfold movement. This mechanism allows the fold and unfold movement of the panels without affect ing the tabbing wire, increasing reliability

Fig. 11 shows an enlargement of fig. 5, with positive magnetic connectors 2 at a bottom side, with negative magnetic connectors 3 at a top side, having a centrally located electrical con ductor 6, and surrounded by electrical insulator 7. The magnetic contacts are placed at the same height on opposite sides of the solar module. This allows the ease interconnection of more than two Miura-Ori modules in series, doubling the power capacity without the need of cables.

The only additional accessory needed will be MC4 Connectors as shown bellow. These connect ors are cheap to obtain, the cable can be design such as to be magnetically connected to each end of the array. This requires a special (but not complex) design of one end of the cable. In this way only a pair of cables will be sufficient for a multi-module array. The length of the cable will be defined by the application, and therefore, the final capacity of the array.

The invention although described in detailed explanatory context may be best under stood in conjunction with the accompanying figures.

It should be appreciated that for commercial application it may be preferable to use one or more variations of the present system, which would similar be to the ones disclosed in the pre sent application and are within the spirit of the invention.

Claims

1. Array (10) of PV-cells, comprising at least n*m PV-cells electrically connected to one and another, wherein in a horizontal direction of the array n>2 and wherein in a vertical direction of the array m>2, wherein each PV-cell has a geometrical form, and at least four magnetic array-array connectors (2,3) for providing electrical array- array contact, at least two magnetic array-array connectors for a positive electrical array-array contact (2), and at least two magnetic array-array connectors for a negative electrical array-array contact (3), wherein at least one positive electrical array-array connector extends in the horizontal di rection and wherein at least one negative electrical array-array connector extends in the horizon tal direction, characterized in wherein at least one positive electrical array-array connector extends in the vertical direc tion and wherein at least one negative electrical array-array connector extends in the vertical di rection, and wherein each connector is electrically insulated, wherein the PV-cells are provided on a backside film, wherein the PV-cells are covered with a frontside film, wherein at an edge of each PV-cell at least two adjacent fold lines (8) are provided for upward movement, and wherein at an edge of each PV-cell at least two adjacent fold lines (9) are provided for downward movement, and wherein the array is adapted to be folded with one single movement such as by compris ing a hinge mechanism for fully folding/unfolding.

2. Array according to claim 1, wherein each cell comprises 2-24 sub-cells (11), and/or wherein an array provides a maximum output of 20-200 W, in particular 30-100W.

3. Array according to claim 1 or 2, wherein the geometrical form is selected from rectangles, such as squares, and paralepidid, such as diamond.

4. Array according to any of claims 1-3, wherein all PV-cells in an array of n*m cells are electri cally connected in series, such as wherein in a column a positive PV-cell (n=i) terminal is electri cally connected (4) to an adjacent negative PV-cell terminal (n=i+l), and wherein a first or last PV-cell (n=n or n=l) terminal of a row (m=j) is electrically connected (4) to an adjacent opposite PV-cell terminal (n=n or n=l, m=j+l), and wherein a first terminal (12) of the first cell (n=l, m=l) is in electrical contact with at least two magnetic array-array connectors (2,3), and wherein a second terminal (13) of the last cell (n=l or n, m=m) is in electrical contact with at least two magnetic array-array connectors (3,2) of opposite electrical polarity.

5. Array according to any of claims 1-4, wherein in case of m=odd the array comprises at least four magnetic array-array connectors for a positive electrical array-array contact (2) provided at one side of the array (the n=l side), of which at least two magnetic array-array connectors (2) at a first edge (m=l), and at least two magnetic array-array connectors (2) at a second edge (m=m), and an electrical connection (5) between the connectors at the first edge and the connectors at the second edge, and at least four magnetic array-array connectors for a negative electrical array-ar ray contact (3) provided at one side of the array (the n=n side), of which at least two magnetic array-array connectors (2) at a first edge (m=l), and at least two magnetic array-array connectors (2) at a second edge (m=m), and an electrical connection (5) between the connectors at the first edge and the connectors at the second edge, or wherein in case of m=even the array comprises at least two magnetic array-array connectors for a positive electrical array-array contact (2) provided at one side of the array (the n=l side) at a first edge (m=l), and at least two magnetic array-array connectors for a negative electrical array-array contact (3) provided at the same side of the array (the n=l side) at a second edge (m=m).

6. Array according to any of claims 1-5, wherein the PV-cells are selected from conventional homo-junction and heterojunction solar cells, mono-facial and bi-facial solar cells, n-type and p- type mono-crystalline Si, micro-crystalline Si bulk, front contacted solar cells, back contacted solar cells, front and rear junction solar cells, interdigitated back contacted solar cells, and com binations thereof, and/or wherein PV-cells have a thickness of 10-100 pm, and/or wherein PV-cells comprise an anti -reflective coating.

7. Array according to any of claims 1-6, wherein the PV-cells are provided on a polymeric back side film, such as a transparent backside film, wherein the polymer is preferably selected from PE, PET, and PP, and/or wherein the backside film has a thickness of 10-100 pm, and/or wherein the PV-cells comprise a polymeric frontside film, such as a transparent frontside film, wherein the polymer is preferably selected from PE, PET, and PP, and/or wherein the frontside film has a thickness of 10-100 pm, and/or wherein a third film is provided on the frontside or backside of the array.

8. Array according to any of claims 1-7, wherein the PV-cells comprise a light-weight encapsula tion layer.

9. Array according to any of claims 1-8, wherein array has a surface area of > 10 cm², and a mass of < 1 gr/cm², and/or wherein the array is portable.

10. Array according to any of claims 1-9, further comprising at least one component selected from a junction box, an electrical connection, a transformer, power electronics, and an electrical power storage unit.

11. Array according to any of claims 1-10, wherein folding is provided by Miura-ori technique, and/or wherein at least one fold line (8,9) comprises at least one hinge (30), wherein the hinge prefera bly comprising at least one insulating material (31,33) at an outer side thereof, and wherein the hinge preferably comprises an electrical connector for connecting a group of cells with an adjacent group of cells.

12. Array according to any of claims 1-11, wherein the magnetic connector is selected from iron comprising materials, and/or wherein magnetic array-array connectors are provided at an edge of the array, preferably at the end of an edge, and/or wherein each magnetic connector individually is located at a fixed position relative to an array, such as at a side thereof at a fixed distance from a corner of the array.

13. Array according to any of claims 1-12, wherein the magnetic connector each individually has a contact area of 0.5-10 cm², preferably 1-5 cm², such as 3.2+1 cm², and/or a diameter of 2+1.3 cm, and/or a thickness of 1-15 mm, preferably 2-10 mm, such as 7 mm, and/or wherein the magnetic connector is a magnet-to-MC4 connector adaptor.

14. System comprising at least two arrays according to any of claims 1-13.

15. System according to claim 14, comprising an embedded charging station, such as for a mo bile phone.

16. System according to claim 14 or 15, comprising power electronics and/or an adaptable junc tion box.