Composite glass cloth for solar cell and application thereof

Abstract

The invention belongs to the technical field of solar cells, and particularly relates to composite glass cloth for a solar cell and application of the composite glass cloth. The glass cloth comprises glass cloth and reinforced epoxy resin attached to the glass cloth, the reinforced epoxy resin comprises epoxy resin powder, liquid epoxy resin, a curing agent and an initiator, and the curing temperature of the reinforced epoxy resin is 130-150 DEG C. According to the technical scheme provided by the invention, the epoxy resin composite glass cloth is additionally arranged on the two sides of the battery piece, so that the problem that a light solar battery assembly is insufficient in strength and cannot pass a hail-resistant experiment is solved; the initiator and the curing agent with corresponding components are matched, so that the surface of the composite glass cloth is not sticky to hands, production, transportation and on-site packaging are facilitated, cross-linking curing can be further performed at a relatively high temperature when a battery piece is finally laminated, and enough bonding strength with an adjacent layer is generated.

Description

Technical Field

[0001] The invention belongs to the technical field of solar cells, and in particular relates to a composite glass cloth for solar cells and an application thereof. Background Art

[0002] The heavy overall weight of solar cell modules limits their application in certain areas with limited load capacity. In order to reduce the weight of the modules, most of them remove the glass and frames and use polymer materials as the front and back panels. The weight of the modules can be reduced by about 70% compared with conventional modules, effectively reducing the unit weight of the modules.

[0003] The structure of a lightweight solar cell module is generally: polymer transparent front plate + encapsulation film + battery cell + encapsulation film + polymer back plate. In the prior art, a lightweight solar cell module is produced by pressing a polymer transparent front plate, an encapsulation film, a battery cell, an encapsulation film and a polymer back plate together.

[0004] However, the polymer materials of the front and back panels generally have poor impact resistance. When used in certain climate environments, they are no longer suitable for meeting the hail resistance test, so they need to be reinforced. The added reinforcement material should be able to improve the impact resistance of lightweight solar cell modules, and also be weather-resistant, have good adhesion with other layers, excellent electrical properties, and be easy to produce and process. Summary of the invention

[0005] The invention provides a composite glass cloth for solar cells and application thereof, which are used to solve the problem of insufficient impact resistance of current lightweight solar cell components.

[0006] In order to solve the above technical problems, the technical solution of the present invention is: the composite glass cloth for solar cells comprises glass cloth and reinforced epoxy resin attached to the glass cloth, the reinforced epoxy resin comprises epoxy resin powder, liquid epoxy resin, curing agent and initiator, and the curing temperature of the reinforced epoxy resin is 130-150°C.

[0007] Optionally, the components of the reinforced epoxy resin are as follows in parts by weight:

[0008]

[0009] Optionally, the epoxy resin powder is solid bisphenol A epoxy resin with an epoxy value of 0.12-0.18 mol / 100g.

[0010] Optionally, the liquid epoxy resin is liquid bisphenol A epoxy resin with an epoxy value of 0.35-0.50 mol / 100g.

[0011] Optionally, the curing agent is selected from tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride or methylhexahydrophthalic anhydride.

[0012] Optionally, the initiator is selected from 2-ethyl-4-methylimidazole, phenylimidazole or N-benzylimidazole.

[0013] Optionally, the preparation method of the composite glass cloth for solar cells comprises the following steps: epoxy resin powder, liquid epoxy resin, curing agent and initiator are mixed in proportion, degassing at 60-70°C to obtain reinforced epoxy resin, then compounding it with a glass cloth coil by spraying, brushing or dipping, drying at 100-120°C, and finally cutting it into pieces for use according to the size requirements of the lightweight components of the solar cell.

[0014] The present invention also provides a lightweight solar cell assembly, which includes a polymer front plate, a packaging film, the composite glass cloth for solar cells, a battery cell, the composite glass cloth for solar cells, a packaging film and a polymer back plate.

[0015] Optionally, the polymer front panel, the packaging film, the composite glass cloth for solar cells, the battery cell, the composite glass cloth for solar cells, the packaging film and the polymer back panel are stacked in sequence and pressed by a press in a vacuum environment at a pressing temperature of 130-150°C for 30-40 minutes.

[0016] Optionally, the packaging film is an EVA (ethylene-vinyl acetate copolymer) film.

[0017] The technical solution provided by the present invention solves the problem that the lightweight solar cell module is not strong enough and cannot pass the hail resistance test by adding epoxy resin composite glass cloth on both sides of the battery cell. The two physical epoxy resins are matched with the initiator and curing agent in corresponding amounts to achieve a non-sticky surface of the composite glass cloth, which is conducive to production, transportation and on-site assembly. When finally pressed into a battery cell, it can be further cross-linked and cured at a higher temperature to produce sufficient bonding strength with adjacent layers. DETAILED DESCRIPTION

[0018] For ease of understanding, the composite glass cloth for solar cells and applications thereof are described below in conjunction with embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0019] Example 1-3 Preparation of composite glass cloth for solar cells

[0020] Epoxy resin powder, liquid epoxy resin, curing agent and initiator are mixed in proportion, degassed at 60-70°C to obtain enhanced epoxy resin, which is then composited with a glass cloth coil by spraying, brushing or dipping. In this embodiment, the coil is immersed in a tank carrying enhanced epoxy resin liquid, dried at 100-120°C, and finally cut into sheets for use according to the size requirements of the solar cell lightweight component. The surface of the composite glass cloth of the prepared solar cell does not stick to your hands, and no release paper is required to isolate the sheet layers, which is convenient for transportation and subsequent process operations.

[0021] The selection and weight proportion of each component of the reinforced epoxy resin described in Examples 1-3 are shown in Table 1.

[0022] Table 1

[0023]

[0024] Epoxy resin E15 is bisphenol A type epoxy resin, powdery, with an epoxy value of 0.14-0.16 mol / 100g, purchased from Huangshan Debang Powder Material Co., Ltd.

[0025] Epoxy resin E44 is a bisphenol A type epoxy resin, a light yellow to brownish yellow high viscosity transparent liquid, an epoxy value of 0.4-0.47 mol / 100g, purchased from Wuxi Pinhua Chemical Co., Ltd.

[0026] Methyltetrahydrophthalic anhydride was purchased from Zhejiang Nanyang Group Co., Ltd., model WNY1002, anhydride content, ≥41.0%.

[0027] 2-Ethyl-4-methylimidazole was purchased from Shanghai Kaisai Chemical Co., Ltd.

[0028] Example 4-6 Preparation of Lightweight Solar Cell Modules

[0029] The polymer front plate, the packaging film, the composite glass cloth for solar cells, the battery cell, the composite glass cloth for solar cells, the packaging film and the polymer back plate are stacked in sequence and pressed by a press in a vacuum environment at a temperature of 130-150° C. for 30-40 minutes.

[0030] The composite glass cloth for solar cells described in Examples 4-6 is prepared in Example 1-3, respectively.

[0031] The material of the polymer front plate is the composite film disclosed in CN108091715A.

[0032] The material of the polymer backplane is the PVDF film disclosed in CN105895722A.

[0033] Comparative Example 1

[0034] The difference from Example 1 is that the epoxy resin 15 is completely replaced by the epoxy resin E44. The surface of the prepared composite glass cloth for solar cells is very sticky and sticky, and release paper needs to be added for isolation and storage, which makes it inconvenient to operate when laminating with other layers later.

[0035] Comparative Example 2

[0036] The difference from Example 1 is that the number of parts of epoxy resin 15 is 40, and the number of parts of epoxy resin E44 is 60. The surface of the prepared composite glass cloth for solar cells is still sticky, but no release paper is provided.

[0037] Comparative Example 3

[0038] The difference from Example 1 is that the epoxy resin 15 has 40 parts, the epoxy resin E44 has 60 parts, and methyltetrahydrophthalic anhydride has 100 parts. The surface of the prepared composite glass cloth for solar cells is not sticky.

[0039] Comparative Example 4

[0040] The difference from Example 1 is that the curing agent is replaced with 55 parts of triethylenediamine. The surface of the prepared composite glass cloth for solar cells is not sticky.

[0041] The difference between Comparative Examples 5-7 and Examples 4-6 is that the composite glass cloths on both sides of the cell are prepared in turn by Comparative Examples 2, 3 and 4. In Comparative Example 2, adhesion occurs between layers during lamination, and it is easy to adhere to other layers when laying a multi-layer structure, making it difficult to lay in place.

[0042] Comparative Example 8

[0043] The difference from Example 4 is that no reinforcing material is provided on both sides of the battery cell.

[0044] Performance Experiment

[0045] In order to verify that the prepared lightweight solar cell backplane meets the requirements of solar cell modules, the solar cell modules of Examples 4-6 and Comparative Examples 5-8 were subjected to weather resistance tests, electrical performance tests, impact resistance tests, bonding strength tests with EVA and bonding strength tests with battery cells. The test results are shown in Table 2.

[0046] Table 2

[0047]

[0048] It can be found from the above experimental data that the various properties of Comparative Example 5 are not much different from those of the embodiment, but the composite glass cloth prepared by Comparative Example 2 is relatively sticky, which is very inconvenient in storage, transportation and subsequent processing.

[0049] Although the composite glass cloth used in Comparative Examples 6 and 7 is not sticky, the epoxy resin is completely cured during the initial drying at 100-120°C, which results in the inability to bond with EVA or battery cells after lamination. Therefore, solar cell modules cannot be produced, and the corresponding performance tests of the battery modules were not carried out.

[0050] The other properties of Comparative Example 8 are similar to those of the embodiments, but it cannot pass the hail test, that is, its impact resistance is not as good as that of the embodiments.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. Although the present invention has been described in detail with reference to the above embodiments, a person skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some or all of the technical features can be replaced by equivalents, and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A composite glass cloth for solar cells, characterized in that: The invention comprises glass cloth and a reinforced epoxy resin attached to the glass cloth. The reinforced epoxy resin comprises epoxy resin powder, liquid epoxy resin, a curing agent and an initiator. The curing temperature of the reinforced epoxy resin is 130-150°C.

2. The composite glass cloth for solar cells according to claim 1, characterized in that: The components of the enhanced epoxy resin are as follows in parts by weight:

3. The composite glass cloth for solar cells according to claim 1, characterized in that: The epoxy resin powder is solid bisphenol A epoxy resin with an epoxy value of 0.12-0.18 mol / 100g.

4. The composite glass cloth for solar cells according to claim 1, characterized in that: The liquid epoxy resin is a liquid bisphenol A type epoxy resin with an epoxy value of 0.35-0.50 mol / 100g.

5. The composite glass cloth for solar cells according to claim 1, characterized in that: The curing agent is selected from tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride or methylhexahydrophthalic anhydride.

6. The composite glass cloth for solar cells according to claim 1, characterized in that: The initiator is selected from 2-ethyl-4-methylimidazole, phenylimidazole or N-benzylimidazole.

7. The composite glass cloth for solar cells according to claim 1, characterized in that: The preparation method of the composite glass cloth for solar cells comprises the following steps: epoxy resin powder, liquid epoxy resin, curing agent and initiator are mixed in proportion, degassing at 60-70° C. to obtain reinforced epoxy resin, then compounding the reinforced epoxy resin with a glass cloth coil by spraying, brushing or dipping, drying at 100-120° C., and finally cutting into pieces according to the size requirements of the solar cell lightweight components for use.

8. A solar cell lightweight component, characterized in that: It comprises a polymer front plate, a packaging film, any composite glass cloth for solar cells as claimed in claims 1-7, a battery cell, any composite glass cloth for solar cells as claimed in claims 1-7, a packaging film and a polymer back plate.

9. The solar cell lightweight assembly according to claim 8, characterized in that: The preparation method comprises the following steps: stacking a polymer front plate, a packaging film, the composite glass cloth for solar cells, a battery cell, the composite glass cloth for solar cells, a packaging film and a polymer back plate in sequence, and pressing them by a press in a vacuum environment at a pressing temperature of 130-150°C for 30-40 minutes.

10. The solar cell lightweight assembly according to claim 8, characterized in that: The packaging film is an EVA film.

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