Method for encapsulating solar cell assemblies

Abstract

The invention relates to a method for encapsulating a solar cell assembly (10). The method has the steps of: providing (S110) a first hybrid laminating film (110) and a second hybrid laminating film (120); forming (S120) a stack (200) comprising the first hybrid laminating film (110), the solar cell assembly (10), and the second hybrid laminating film (120), the solar cell assembly (10) being situated between the first hybrid laminating film (110) and the second hybrid laminating film (120); and fusing (S130) the first hybrid laminating film (110) and the second hybrid laminating film (120) in order to encapsulate the solar cell assembly (10). The first hybrid laminating film and the second hybrid laminating film comprise, in an inner region (112, 122), an encapsulation material for encapsulating the solar cell assembly and, in an edge region (114, 122) surrounding the inner region, a sealing material. The sealing material differs from the encapsulation material in order to form a laterally water-impermeable seal.

Description

[0001] IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 08 / 27 / 2025

[0002] Encapsulation process for solar cell arrays

[0003] The present invention relates to a method for encapsulating a solar cell arrangement and to a hybrid laminating film.

[0004] BACKGROUND

[0005] A photovoltaic module comprises an internal array of solar cells that must be reliably protected from moisture and dirt. This array is a network of interconnected solar cells. For example, a photovoltaic module can be constructed as a glass-glass module, in which the solar cell array is embedded between two glass panes within an encapsulating material. The lateral edges between the two glass panes are protected from moisture ingress with a sealant. This sealant ensures a secure and tight bond between the glass panes. Photovoltaic modules manufactured in this way should be reliably protected from water or moisture ingress, even under fluctuating temperature conditions.

[0006] One disadvantage of conventional manufacturing is that encapsulation and sealing are two separate process steps, making the manufacturing process complex.

[0007] Therefore, there is a need for simplified methods for encapsulating solar cell arrays.

[0008] Brief description of the invention

[0009] At least some of the problems mentioned above are solved by a method for encapsulating a solar cell arrangement according to claim 1. The dependent claims relate to further advantageous embodiments of the method.

[0010] Page 1 of 18 IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 27.08.2025

[0011] The present invention relates to a method for encapsulating a solar cell arrangement. The method comprises:

[0012] - Providing a first hybrid laminating film and a second hybrid laminating film;

[0013] - Forming a stack comprising the first hybrid laminating film, the solar cell array, and the second hybrid laminating film, wherein the solar cell array is positioned between the first hybrid laminating film and the second hybrid laminating film; and

[0014] - Merging the first hybrid laminating film and the second hybrid laminating film to encapsulate the solar cell array.

[0015] The first hybrid laminating film and the second hybrid laminating film each comprise an encapsulation material in an inner area for encapsulating the solar cell array and a sealing material in a surrounding outer area. The sealing material differs from the encapsulation material in order to form a laterally watertight seal (after fusion).

[0016] Encapsulation (or lamination) refers to a process of embedding. In this process, the solar cell array is completely enveloped by the encapsulation material (except for the electrical leads). The fusing can take place in a vacuum under heat treatment and pressure, ideally resulting in a completely void-free encapsulation.

[0017] Optionally, the stacking step includes arranging the first hybrid laminating film, the solar cell array, and the second hybrid laminating film between a first and a second glass pane. The waterproof seal then extends from the first to the second glass pane. In other words, the seal creates a watertight seal in the gap between the two glass panes at the edges. This allows for the efficient production of glass-glass photovoltaic modules.

[0018] Page 2 of 18 IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 27.08.2025

[0019] Optionally, the stacking step includes removing a first protective film, at least from the edge of the first hybrid laminating film, and / or removing a second protective film, at least from the edge of the second hybrid laminating film. The protective film(s) can serve to protect the sealing material. The sealing material is often very sticky, and the protective film can effectively protect it from dust. Furthermore, they prevent the hybrid laminating films from sticking together during transport (e.g., when rolled up).

[0020] Optionally, the step of preparing (the hybrid laminating films) includes the following:

[0021] - Providing a laminating film containing encapsulation material,

[0022] - Providing a frame which has sealing material and defines an interior area, wherein the interior area can be covered by the laminating film and the frame extends laterally beyond the laminating film,

[0023] - Framing the laminating film with the frame, wherein the framing includes partially or fully connecting the frame with the laminating film in an overlap area.

[0024] The fact that the inner area can be (completely) covered by the laminating film means that there is a certain overlap, which can then be used to bond the laminating film to the frame (e.g., by gluing, fusing, etc.). The bond should be strong enough that the resulting hybrid laminating film can be processed by the appropriate laminating machines. Therefore, hybrid laminating films can also be understood as composite films and are not necessarily monolithic.

[0025] Optionally, the deployment step includes the following:

[0026] Providing a laminating film which contains encapsulation material, and

[0027] Page 3 of 18 IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 27.08.2025

[0028] Activating an edge area of ​​the laminating film to create the sealing material.

[0029] Activation can include at least one of the following: irradiation, chemical treatment, thermal treatment, or mechanical treatment. The laminating film with the (activated) edge area then forms the first hybrid laminating film and / or the second hybrid laminating film.

[0030] Optionally, the laminating film includes a precursor material of the sealing material in the edge area, and the activation step can be carried out by adding a second component to (chemically) create the sealing material. Thus, the sealing material can be designed or created as a two-component adhesive.

[0031] Optionally, the deployment step includes the following:

[0032] - Providing a base film made of an encapsulation material, and

[0033] - Applying a frame of sealing material to the base film.

[0034] The base film with the frame then forms the first hybrid laminating film and / or the second hybrid laminating film. The base film can thus serve as a substrate for the frame. For example, the sealing material can also be deposited directly onto the base film. According to the exemplary embodiments, the sealing material can again be covered with a protective film that can be removed before fusion.

[0035] Optionally, another base film is applied to the frame, so that the frame is positioned between the base film and the second base film. The base films together with the interposed frame then form the first hybrid laminating film and / or the second hybrid laminating film.

[0036] Page 4 of 18 IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 27.08.2025

[0037] Optionally, another frame is applied to the base film, so that the base film is positioned between the first frame and the second frame (and can again serve as a substrate). Both frames with the base film in between form the first hybrid laminating film and / or the second hybrid laminating film.

[0038] It is understood that during the fusing process (e.g., under heat and / or pressure), the sealing material can flow or be forced out laterally. For example, under heat, the sealing material may be less viscous than the encapsulation material. This results in a lateral bonding or sealing of the two opposing, for example, glass panes. The encapsulation material of the base film, on the other hand, can remain inside and securely encapsulate the solar cell array.

[0039] Optionally, the sealing material contains (or is made of) butyl. The encapsulation material may contain or be made of at least one of the following materials:

[0040] Ethylene Vinyl Acetate (EVA), Polyvinyl Butyral (PVB), Thermoplastic Polyolefin (TPO).

[0041] Exemplary embodiments also relate to a hybrid laminating film for encapsulating a solar cell arrangement, wherein the hybrid laminating film has the following features:

[0042] - an inner area made of an encapsulation material for encapsulating the solar cell array; and

[0043] - a border area surrounding the interior, which has a sealing material.

[0044] Page 5 of 18 IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 27.08.2025

[0045] The sealing material differs from the encapsulation material in order to provide a laterally watertight seal for the solar cell arrangement.

[0046] Exemplary embodiments also relate to a glass-glass photovoltaic module with two glass panes and a stack arranged between them, which has the following features:

[0047] - a first hybrid laminating film;

[0048] - a solar cell array;

[0049] - a second hybrid laminating film, wherein the solar cell arrangement is located between the first hybrid laminating film and the second hybrid laminating film.

[0050] Exemplary embodiments offer the advantage of simplified manufacturing, where encapsulation and sealing do not have to be carried out as separate steps, but rather the encapsulation (or lamination) automatically results in a seal (e.g. of the space between a front and back glass).

[0051] BRIEF DESCRIPTION OF THE FIGURES

[0052] The embodiments of the present invention are better understood from the following detailed description and the accompanying drawings, which, however, should not be understood as limiting the disclosure to the specific embodiments, but merely serve for explanation and understanding.

[0053] Fig. 1 shows a schematic flowchart for a method for encapsulating a solar cell arrangement according to an exemplary embodiment.

[0054] Fig. 2 illustrates the encapsulation of the solar cell arrangement between two glass panes according to exemplary embodiments.

[0055] Page 6 of 18 IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 27.08.2025

[0056] Fig. 3 shows the solar cell arrangement encapsulated and sealed according to exemplary embodiments.

[0057] Fig. 4 shows an embodiment for the production of a hybrid laminating film.

[0058] Fig. 5 shows another embodiment of a hybrid laminating film.

[0059] DETAILED DESCRIPTION

[0060] Fig. 1 shows a schematic flowchart for a method for encapsulating a solar cell array according to an exemplary embodiment. The method comprises the following steps:

[0061] - Provide S110 of a first hybrid laminating film 110 and a second hybrid laminating film 120;

[0062] - Forming S120 of a stack 200 with the first hybrid laminating film 110, the solar cell arrangement 10 and the second hybrid laminating film 120, wherein the solar cell arrangement 10 is arranged between the first hybrid laminating film 110 and the second hybrid laminating film 120; and

[0063] - S130 merges the first hybrid laminating film 110 and the second hybrid laminating film 120 to encapsulate the solar cell arrangement 10.

[0064] Fig. 2 illustrates further details of the encapsulation of the solar cell arrangement 10. The stack 200 shown comprises the solar cell arrangement 10, which is arranged between the first hybrid laminating film 110 and the hybrid laminating film 120. The stack 200 further comprises a first glass sheet 210 and a second glass sheet 220, between which the first hybrid laminating film 110, the second hybrid laminating film 120, and the solar cell arrangement 10 are located.

[0065] The first hybrid laminating film 110 and the second hybrid laminating film 120 each have an encapsulation material for encapsulation in an inner area 112, 122.

[0066] Page 7 of 18 IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 27.08.2025 of the solar cell arrangement 10. In an edge region 114, 124, which surrounds the inner region 112, 122, the hybrid laminating foils 110, 120 have a sealing material. The sealing material differs from the encapsulation material in order to form a laterally watertight seal between the first glass pane 210 and the second glass pane when fused.

[0067] Figures 3A and 3B show the result of the encapsulation process, with Figure 3A showing a sectional view and Figure 3B a top view (e.g., through the front glass pane). The encapsulation is achieved via the fusion step S130, where the stack 200 is compressed, for example, by heating in a vacuum, so that the laminate 112, 122 forms between the two glass panes 210, 220, and the solar cell arrangement 10 is embedded (encased) therein. It is laterally enclosed by the seal 114, 124. Since this can be done completely (see Figure 3B), only the connecting leads (not shown) protrude through the laminate 112, 122 or the seal 114, 124.

[0068] During sealing, the sealing material from the two edge areas 112, 122 fuses together and forms a tight bond with the two glass panes 210, 220. The sealing material is designed to provide a watertight lateral seal.

[0069] According to the exemplary embodiments, encapsulation takes place in a laminating machine. Materials used for encapsulation include, for example, ethylene vinyl acetate (EVA), polyvinyl butyral (PVB), and thermoplastic polyolefin (TPO). EVA is advantageous because it adheres well and is durable. An advantage of TPO is its excellent resistance to UV radiation and its ability to be processed at lower temperatures, which contributes to energy savings.

[0070] According to the exemplary embodiments, butyl can be used as a sealing material, for example. Since butyl adheres very well even at room temperature, the edge area 114, 124 is optionally protected with a protective film (e.g., against dust or other contaminants).

[0071] Page 8 of 18 IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 27.08.2025 (adhere to other laminating films). Accordingly, in exemplary embodiments, before the fusing step, the protective film can be peeled off the edge region 114 of the first hybrid laminating film 110 and / or from the edge region 124 of the second hybrid laminating film 120.

[0072] Fig. 4 shows an embodiment for the production of a hybrid laminating film (i.e., the first / second hybrid laminating film 110, 120). First, a frame 114, which has sealing material and defines an inner area, can be provided. The frame 114 itself can be an adhesive tape onto which the sealing material is applied and which is optionally protected by a protective film. Furthermore, a laminating film 112 made of encapsulating material can be used to cover the inner area of ​​the frame 114. For example, the (rectangular) frame 114 can have an outer height of d4, an outer width d3, an inner height d6, and an inner width ds. The (rectangular) laminating film can have a height d2 and a width di. According to embodiments, these dimensions are chosen such that the following holds true: d3 > di > d5 and d4 > d2 > d6. (1)

[0073] In other words, the frame 114 can enclose the laminating film 112 with an overlap (since di > d5 and d2 > d6). Therefore, the frame 114 can be partially (e.g., spot-locked) or fully bonded (e.g., glued or welded) to the laminating film 112 in the overlap area. The result is the hybrid laminating film 110, 120.

[0074] Fig. 5 shows a further embodiment for the production of a hybrid laminating film (i.e., the first / second hybrid laminating film 110, 120). In this embodiment, a laminating film 112 with or made of encapsulation material is first provided, wherein the laminating film 112 in this embodiment has an edge region 114 in which the sealing material can be generated by activation. Optionally, a pre-

[0075] Page 9 of 18 IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 27.08.2025 The runner material of the sealing material must be present. Activation can include at least one of the following: irradiation, chemical treatment, thermal treatment, or mechanical treatment. The laminating foil 112 with the activated or activatable edge region 114 then forms the first hybrid laminating foil 110 and / or the second hybrid laminating foil 120.

[0076] Irradiation can trigger a chemical or physical process that creates the sealing material. Chemical treatment might involve, for example, adding a second component to the precursor material, resulting in a two-component adhesive. Mechanical treatment might involve applying pressure, for instance, to release the sealing material from (micro)encapsulations. Thermal treatment might liquefy the sealing material. The thermal and / or mechanical treatment can be performed together with or separately from the fusing step.

[0077] According to further embodiments, a base film 112 made of an encapsulation material can first be provided (e.g., as in Fig. 4 with d2=d4 and di=d3), onto which a frame 114 made of sealing material is applied. The base film 112 can therefore be used as a substrate for the sealing material, which can be deposited directly onto the surface of the base film 112.

[0078] According to further embodiments, another base film made of encapsulation material can be applied to the frame 114. The frame 114 would then be positioned between the base film 112 and the additional base film. The sealing material would thus be protected on both sides by base films made of encapsulation material (an additional protective film would not be necessary). The amount of sealing material can be chosen to be sufficiently high so that, during the melting step S130 (and / or when pressure is applied), the sealing material is forced laterally out of the hybrid laminating film 110, 120 to achieve lateral sealing.

[0079] Page 10 of 18 IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 27.08.2025

[0080] According to further embodiments, another frame (instead of another base film) can be applied, so that the base film 112 is arranged between the frame 114 and the further frame. Here, appropriate protective films on the frame would be advantageous (to protect the sealing material).

[0081] Thus, the hybrid laminating films 110, 120 can be produced in different ways, all of which should be covered by the protection.

[0082] Exemplary embodiments overcome the problems of conventional methods for encapsulating solar cells by using hybrid laminating films 110, 120, which have an encapsulation material in an inner region 112, 122 and (at least) a sealing material in an outer region 114, 124. Using these hybrid laminating films 110, 120, the lamination (encapsulation) steps of the solar cell arrangement 10 can be carried out simultaneously with the sealing of the exemplary glass-glass modules. The sealing creates a liquid-tight connection between the two glass panes, so that neither moisture nor water can penetrate the space between the two opposing glass panes.

[0083] This type of encapsulation can be advantageously used for so-called tandem cell technology, where a tandem cell comprises at least two subcells that, for example, have different absorption wavelength ranges. They utilize a broader electromagnetic spectrum for power generation. Therefore, exemplary embodiments also refer to tandem glass-glass modules that are sealed between the glass layers at low pressure.

[0084] The features of the invention disclosed in the description, claims and figures may be essential for the realization of the invention, either individually or in any combination.

[0085] Page 11 of 18 IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 27.08.2025

[0086] REFERENCE MARK LIST

[0087] 10 solar cell arrangement no first hybrid laminating film

[0088] 120 times hybrid laminating film

[0089] 112,122 Indoor area

[0090] 114,124 marginal area

[0091] 200 stacks (for encapsulation)

[0092] 210 a first pane of glass

[0093] 220 a second glass pane di, d2,... various lengths and widths

[0094] Page 12 of 18

Claims

IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 08 / 27 / 2025 REQUIREMENTS 1. Method for encapsulating a solar cell arrangement (10) with: Providing (S110) a first hybrid laminating film (110) and a second hybrid laminating film (120); Forming (S120) a stack (200) with the first hybrid laminating film (110), the solar cell arrangement (10) and the second hybrid laminating film (120), wherein the solar cell arrangement (10) is arranged between the first hybrid laminating film (110) and the second hybrid laminating film (120); and Fusion (S130) of the first hybrid laminating film (110) and the second hybrid laminating film (120) to encapsulate the solar cell arrangement (10), wherein the first hybrid laminating film (110) and the second hybrid laminating film (120) have an encapsulation material in an inner region (112, 122) for encapsulating the solar cell arrangement (10) and have a sealing material in a rim region (114, 122) surrounding the inner region (112, 122), and wherein the sealing material is different from the encapsulation material to form a laterally watertight seal.

2. The method of claim 1, wherein the step of forming (S120) a stack (200) further comprises: Arranging (S124) the first hybrid laminating film (110), the solar cell arrangement (10) and the second hybrid laminating film (120) between a first glass pane (210) and a second glass pane (220), wherein the water-impermeable seal extends from the first glass pane Page 13 of 18 IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 08 / 27 / 2025 (210) extends to the second glass pane (220).

3. A method according to claim 1 or claim 2, wherein the step of forming (S120) the stack (200) further comprises: Removing a first protective film at least from the edge area (114) of the first hybrid laminating film (110) and / or removing a second protective film at least from the edge area (124) of the second hybrid laminating film (120), wherein the protective film protects the sealing material.

4. Method according to any one of claims 1 to 3, wherein the step (S110) of providing further comprises: Providing a laminating film (112) which contains encapsulation material; Providing a frame (114) which has sealing material and defines an interior area, wherein the interior area can be covered by the laminating film (112) and the frame (114) extends laterally beyond the laminating film (112); Framing the laminating film (112) with the frame (114), wherein the framing comprises partially or fully connecting the frame (114) with the laminating film (112) in an overlap area.

5. Method according to any one of claims 1 to 4, wherein the provisioning step (S110) further comprises: Providing a laminating film (112) which contains encapsulation material; Page 14 of 18 IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 08 / 27 / 2025 Activating an edge region (114) of the laminating film (112) to produce the sealing material, wherein the activation comprises at least one of the following: irradiation, chemical treatment, thermal treatment, mechanical treatment, and wherein the laminating film (112) with the activated or activatable edge region (114) forms the first hybrid laminating film (110) and / or the second hybrid laminating film (120).

6. Method according to claim 5, wherein the laminating film (112) has a precursor material of the sealing material in the edge region (114) and the activation step comprises adding a second component to create the sealing material.

7. Method according to any one of claims 1 to 6, wherein the provisioning step (S110) further comprises: Providing a base film (112) made of an encapsulation material, Applying a frame (114) made of sealing material to the base film (112), wherein the base film (112) together with the frame (114) forms the first hybrid laminating film (110) and / or the second hybrid laminating film (120).

8. Method according to claim 7, wherein a further base film is applied to the frame, such that the frame (114) is arranged between the base film (112) and the further base film and the base films (112) together with the frame (114) arranged between them form the first hybrid laminating film (110) and / or the second hybrid laminating film (120).

9. Method according to claim 7, wherein a further frame (114) is applied Page 15 of 18 IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 27.08.2025, such that the base foil (112) is arranged between the frame (114) and the further frame, wherein both frames (114) with the base foil (112) arranged between them form the first hybrid laminating foil (110) and / or the second hybrid laminating foil (120).

10. Method according to any one of claims 1 to 9, wherein the sealing material comprises butyl and / or the encapsulation material comprises or is at least one of the following materials: Ethylene Vinyl Acetate, EVA, Polyvinyl Butyral, PVB, Thermoplastic Polyolefin, TPO.

11. Hybrid laminating film (110) for encapsulating a solar cell arrangement (10), comprising: an inner region (112) made of an encapsulation material for encapsulating the solar cell arrangement (10); and a rim region (114) surrounding the inner region (112), which has a sealing material, wherein the sealing material differs from the encapsulation material to enable a laterally watertight seal for the solar cell arrangement (10).

12. Glass-glass photovoltaic module with two glass sheets (210, 220) and stack (200) arranged between them, wherein the stack (200) comprises: a first hybrid laminating film (110); a solar cell arrangement (10); Page 16 of 18 IR-2024-0008 / 126-0051 - Hybrid Foil Sealing 27.08.2025 a second hybrid laminating foil (120) wherein the solar cell arrangement (10) is arranged between the first hybrid laminating foil (110) and the second hybrid laminating foil (120). Page 17 of 18

Images