A light reflecting enhancement film and an enhanced photovoltaic module having the same

Abstract

The application discloses a light reflection and enhancement film and an enhanced photovoltaic module with the same, the light reflection and enhancement film comprises a buffer layer and a substrate layer, the preparation raw materials of the buffer layer comprise an ethylene polymer, a mesoporous composite material, a filler and an additive, and the preparation raw materials of the substrate layer comprise a propylene polymer alloy, the mesoporous composite material, the filler and the additive. The light reflection and enhancement film and the enhanced photovoltaic module with the same have the advantages that the mesoporous material is compounded with the nanometer material to form the mesoporous composite material, and then the mesoporous composite material is used for preparing the buffer layer and the substrate layer, so that the reflectivity of the ultraviolet region of 330-380 nm, the adhesion between the buffer layer and the battery and the adhesion between the substrate layer and the adhesive film are improved, the light reflection and enhancement film is applied to the gap position between the battery pieces on the photovoltaic battery, the battery hidden crack and the fragments can be avoided, and the module power can be greatly improved compared with the application on the glass.

Description

Technical Field

[0001] This invention belongs to the field of photovoltaic module technology, specifically relating to a reflective enhancement film and an enhanced photovoltaic module having the same. Background Technology

[0002] Grid parity for photovoltaic (PV) systems and cost reduction and efficiency improvement have always been important research topics in the industry. The gaps between PV module cells account for approximately 3-7% of the entire module. Various methods, such as enamel coatings, paints, and reflective materials, can be used to utilize this light, causing total internal reflection at the glass-air interface of the PV module, thus returning the light to the cells and increasing the module's output power. Regardless of the method, current reflective materials are limited to application to the back glass or backsheet. However, due to the presence of a certain thickness of encapsulating film between the back glass or backsheet and the cells, applying reflective materials to the back glass or backsheet results in light loss, failing to maximize light utilization. Furthermore, changing the placement of reflective materials can easily cause microcracks or fragmentation of the cells. Summary of the Invention

[0003] To address the technical problems existing in the prior art, the present invention aims to provide a reflective enhancement film and an enhanced photovoltaic module having the same.

[0004] To achieve the above objectives and technical effects, the technical solution adopted by this invention is as follows:

[0005] A reflective enhancement film includes a buffer layer and a substrate layer. The raw materials for preparing the buffer layer include ethylene polymers, mesoporous composite materials, fillers, and additives. The raw materials for preparing the substrate layer include propylene polymer alloys, mesoporous composite materials, fillers, and additives.

[0006] Furthermore, by weight, the buffer layer comprises the following components:

[0007] 55-93 parts of ethylene polymers

[0008] 2-12 parts of mesoporous composite material

[0009] 5-30 parts of filler

[0010] Additives: 0.1-3 parts.

[0011] Furthermore, by weight, the substrate layer comprises the following components:

[0012] 57-90 parts of propylene polymer alloy

[0013] 5-25 parts of mesoporous composite material

[0014] 5-25 parts of filler

[0015] Additives: 0.1-3 parts.

[0016] Furthermore, the mesoporous composite material is formed by combining a mesoporous material and a nanomaterial. The mesoporous material is selected from at least one of MCM-41, SBA-15, and MCM-48, and the nanomaterial is selected from at least one of nano zinc oxide, nano calcium carbonate, and nano barium sulfate. The particle size of the nanomaterial is 10-200 nm.

[0017] Furthermore, the thickness of the buffer layer is 30-100 μm, and the thickness of the substrate layer is 20-100 μm; the propylene polymer alloy is an alloy of propylene polymer and ethylene polymer.

[0018] Furthermore, the ethylene polymer has a melting point of 70-120℃ and a hardness of <80A, and is selected from one or more combinations of polyethylene, ethylene-octene copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, maleic anhydride-grafted ethylene-butene copolymer, maleic anhydride-grafted ethylene-octene copolymer, and maleic anhydride-grafted ethylene-hexene copolymer.

[0019] Furthermore, the propylene polymer is selected from one or more combinations of homopolymer polypropylene, copolymer polypropylene, and block polypropylene.

[0020] Furthermore, the filler is selected from one or more combinations of titanium dioxide, calcium carbonate, talc, mica, barium sulfate, silicon dioxide, and glass microspheres.

[0021] Furthermore, the additives include antioxidants and light stabilizers, wherein the antioxidants are primary antioxidants or a mixture of primary and secondary antioxidants, and the light stabilizers are ultraviolet absorbers and / or ultraviolet stabilizers.

[0022] The present invention also discloses an efficiency-enhancing photovoltaic module, including a reflective efficiency-enhancing film as described above, wherein the reflective efficiency-enhancing film is laid in the gap between the photovoltaic module cells and the lower encapsulation film.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] This invention discloses a reflective enhancement film and an enhanced photovoltaic module having the same. By compounding mesoporous materials and nanomaterials to form a mesoporous composite material, which is then used to prepare a buffer layer and a substrate layer, it is beneficial to improve the reflectivity in the 330-380nm ultraviolet region, the adhesion between the buffer layer and the battery, and the adhesion between the substrate layer and the adhesive film. By applying the reflective enhancement film to the gap between the cells on the photovoltaic cell, microcracks and fragments of the cell can be avoided. Compared with applying it to glass, the module power can be significantly improved. Detailed Implementation

[0025] The present invention will now be described in detail so that its advantages and features can be more easily understood by those skilled in the art, thereby providing a clearer and more explicit definition of the scope of protection of the present invention.

[0026] The following provides a brief overview of one or more aspects to offer a basic understanding of them. This overview is not an exhaustive summary of all conceived aspects, nor is it intended to identify key or decisive elements of all aspects, nor to define the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form to prepare for the more detailed descriptions that follow.

[0027] This invention discloses a reflective enhancement film, comprising a buffer layer and a substrate layer. The thickness of the buffer layer is 30-100μm, and the thickness of the substrate layer is 20-100μm. The reflective enhancement film is applied to the gap between the cells of a photovoltaic cell and fixed by positioning tape.

[0028] The raw materials for preparing the buffer layer include ethylene polymers, mesoporous composite materials, fillers, and additives. By weight, the buffer layer comprises the following components:

[0029] 55-93 parts of ethylene polymers

[0030] 2-12 parts of mesoporous composite material

[0031] 5-30 parts of filler

[0032] Additives: 0.1-3 parts.

[0033] The raw materials for preparing the substrate layer include propylene polymer alloys, mesoporous composite materials, fillers, and additives. By weight, the substrate layer comprises the following components:

[0034] 57-90 parts of propylene polymer alloy

[0035] 5-25 parts of mesoporous composite material

[0036] 5-25 parts of filler

[0037] Additives: 0.1-3 parts.

[0038] Mesoporous composite materials are formed by combining mesoporous materials and nanomaterials. The mesoporous materials are selected from at least one of MCM-41, SBA-15, and MCM-48, and the nanomaterials are selected from at least one of nano zinc oxide, nano calcium carbonate, and nano barium sulfate. The particle size of the nanomaterials is 10-200 nm.

[0039] Propylene polymer alloys are alloys of propylene polymers and ethylene polymers, with the proportion of propylene polymers in the propylene polymer alloy being >55%.

[0040] The melting point of ethylene polymers is 70-120℃, and the hardness is <80A. They are selected from one or more combinations of polyethylene, ethylene-octene copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, maleic anhydride-grafted ethylene-butene copolymer, maleic anhydride-grafted ethylene-octene copolymer, and maleic anhydride-grafted ethylene-hexene copolymer.

[0041] The propylene polymers are selected from one or more combinations of homopolymer polypropylene, copolymer polypropylene, and block polypropylene.

[0042] The filler is selected from one or more of titanium dioxide, calcium carbonate, talc, mica, barium sulfate, silicon dioxide, and glass microspheres.

[0043] The additives include antioxidants and light stabilizers. The antioxidants are primary antioxidants or a mixture of primary and secondary antioxidants, and the light stabilizers are ultraviolet absorbers and / or ultraviolet stabilizers.

[0044] The main antioxidant is a hindered phenolic antioxidant (such as antioxidant 1010) or a hindered phenolic phosphite synergistic antioxidant.

[0045] The secondary antioxidants are phosphite or thioester antioxidants.

[0046] The ultraviolet absorber is selected from one or more of benzophenone, benzotriazole or triazine ultraviolet absorbers.

[0047] UV stabilizers are hindered amine UV stabilizers, such as light stabilizer 2020.

[0048] The present invention also discloses an efficiency-enhancing photovoltaic module, comprising, from front to back, a front glass panel, a front encapsulation film, a battery, a reflective efficiency-enhancing film, a rear encapsulation film, and a back glass or back sheet.

[0049] This invention also discloses a method for preparing an efficiency-enhancing photovoltaic module, comprising the following steps:

[0050] Lay the front glass panel → Lay the front sealing film → Lay the battery → Lay reflective enhancement film between the battery cells (laid longitudinally and laterally separately) → Apply positioning tape → Lay the rear sealing film → Lay the back glass or back panel; then proceed to the laminator for lamination.

[0051] Example 1

[0052] A reflective enhancement film includes a buffer layer and a substrate layer. The reflective enhancement film is applied to the gaps between the cells of a photovoltaic cell and fixed by positioning tape.

[0053] By weight, the buffer layer comprises the following components:

[0054] 62.4 parts of ethylene-butene copolymer

[0055] 12 parts of mesoporous composite material

[0056] 25 parts titanium dioxide

[0057] Antioxidant 1010 0.1 parts

[0058] Light stabilizer 2020 0.5 parts.

[0059] The melting point of the ethylene-butene copolymer is 85℃, and its Shore hardness is 52A.

[0060] By weight, the substrate layer comprises the following components:

[0061] 38 parts of copolymerized polypropylene

[0062] 26.4 parts of polyethylene

[0063] 10 parts of mesoporous composite material

[0064] 25 parts titanium dioxide

[0065] Antioxidant 1010 0.1 parts

[0066] Light stabilizer 2020 0.5 parts.

[0067] The mesoporous composite material is a composite of SBA-15 and nano-barium sulfate.

[0068] A method for preparing a reflective enhancement film includes the following steps:

[0069] 1) Weigh 62.4 parts of ethylene-butene copolymer, 12 parts of mesoporous composite material, 25 parts of titanium dioxide, 0.1 parts of antioxidant 1010 and 0.5 parts of light stabilizer 2020, add them into the extruder and mix evenly. Then, extrude and granulate at 220℃ and dry to obtain buffer layer masterbatch.

[0070] Weigh out 38 parts of copolymer polypropylene, 26.4 parts of polyethylene, 10 parts of mesoporous composite material, 25 parts of titanium dioxide, 0.1 parts of antioxidant 1010 and 0.5 parts of light stabilizer 2020, add them to the extruder and mix evenly. Then, extrude and granulate at 220℃ and dry to obtain substrate layer masterbatch.

[0071] 2) The buffer layer masterbatch and the substrate layer masterbatch are extruded through a multi-layer casting machine to obtain the desired reflective enhancement film. The thickness of the buffer layer is 50μm and the thickness of the substrate layer is 50μm.

[0072] A method for preparing an efficiency-enhancing photovoltaic module includes the following steps:

[0073] Lay the front glass panel → Lay the front sealing film → Lay the battery → Lay reflective enhancement film between the battery cells (the buffer layer faces the battery side, and is laid longitudinally and laterally) → Apply positioning tape → Lay the rear sealing film → Lay the back glass or back panel; then proceed to the laminator for lamination.

[0074] Example 2

[0075] By weight, the buffer layer comprises the following components:

[0076] 67.4 parts of ethylene-octene copolymer

[0077] 7 parts of mesoporous composite material

[0078] 25 parts titanium dioxide

[0079] Antioxidant 1010 0.1 parts

[0080] Light stabilizer 2020 0.5 parts.

[0081] The melting point of the ethylene-octene copolymer is 82°C, and its Shore hardness is 66A.

[0082] By weight, the substrate layer comprises the following components:

[0083] 40 parts of copolymerized polypropylene

[0084] 27.4 parts of polyethylene

[0085] 7 parts of mesoporous composite material

[0086] 25 parts titanium dioxide

[0087] Antioxidant 1010 0.1 parts

[0088] Light stabilizer 2020 0.5 parts.

[0089] The mesoporous composite material is a composite of MCM-41 and nano zinc oxide.

[0090] The rest is the same as in Example 1.

[0091] Example 3

[0092] By weight, the buffer layer comprises the following components:

[0093] 69.4 parts of ethylene-butene copolymer

[0094] 5 parts of mesoporous composite material

[0095] 25 parts titanium dioxide

[0096] Antioxidant 1010 0.1 parts

[0097] Light stabilizer 2020 0.5 parts.

[0098] The ethylene-butene copolymer has a melting point of 85°C and a Shore hardness of 52A. By weight, the substrate layer comprises the following components:

[0099] 40 parts of copolymerized polypropylene

[0100] 29.4 parts of polyethylene

[0101] 5 parts of mesoporous composite material

[0102] 25 parts titanium dioxide

[0103] Antioxidant 1010 0.1 parts

[0104] Light stabilizer 2020 0.5 parts.

[0105] The mesoporous composite material is a composite of MCM-48 and nano-calcium carbonate. The rest is the same as in Example 1.

[0106] Comparative Example 1

[0107] By weight, the buffer layer comprises the following components:

[0108] 62.4 parts of ethylene-butene copolymer

[0109] SBA-15 12 copies

[0110] 25 parts titanium dioxide

[0111] Antioxidant 1010 0.1 parts

[0112] Light stabilizer 2020 0.5 parts.

[0113] The ethylene-butene copolymer has a melting point of 85°C and a Shore hardness of 52A. By weight, the substrate layer comprises the following components:

[0114] 38 parts of copolymerized polypropylene

[0115] 26.4 parts of polyethylene

[0116] SBA-15 10 copies

[0117] 25 parts titanium dioxide

[0118] Antioxidant 1010 0.1 parts

[0119] Light stabilizer 2020 0.5 parts.

[0120] The rest is the same as in Example 1.

[0121] Comparative Example 2

[0122] By weight, the buffer layer comprises the following components:

[0123] 62.4 parts of ethylene-butene copolymer

[0124] 12 parts of nano barium sulfate

[0125] 25 parts titanium dioxide

[0126] Antioxidant 1010 0.1 parts

[0127] Light stabilizer 2020 0.5 parts.

[0128] The ethylene-butene copolymer has a melting point of 85°C and a Shore hardness of 52A. By weight, the substrate layer comprises the following components:

[0129] 38 parts of copolymerized polypropylene

[0130] 26.4 parts of polyethylene

[0131] 10 parts of nano barium sulfate

[0132] 25 parts titanium dioxide

[0133] Antioxidant 1010 0.1 parts

[0134] Light stabilizer 2020 0.5 parts.

[0135] The rest is the same as in Example 1.

[0136] Comparative Example 3

[0137] By weight, the buffer layer comprises the following components:

[0138] 62.4 parts of ethylene-butene copolymer

[0139] 37 parts of titanium dioxide

[0140] Antioxidant 1010 0.1 parts

[0141] Light stabilizer 2020 0.5 parts.

[0142] The ethylene-butene copolymer has a melting point of 85°C and a Shore hardness of 52A. By weight, the substrate layer comprises the following components:

[0143] 38 parts of copolymerized polypropylene

[0144] 26.4 parts of polyethylene

[0145] 35 parts titanium dioxide

[0146] Antioxidant 1010 0.1 parts

[0147] Light stabilizer 2020 0.5 parts.

[0148] The rest is the same as in Example 1.

[0149] Comparative Example 4

[0150] The difference between this comparative example and Example 1 is that in this comparative example, only the substrate layer is fixed at the gap between the cells on the photovoltaic cell by positioning tape. The thickness of the substrate layer is 100μm, and there is no buffer layer.

[0151] The rest is the same as in Example 1.

[0152] Comparative Example 5

[0153] The difference between this comparative example and Example 1 is that in this comparative example, the reflective enhancement film is fixed to the back glass of the photovoltaic cell. The specific steps are as follows:

[0154] Laying the front glass panel → Laying the front sealing film → Laying the battery → Laying the rear sealing film → Laying the back glass containing the reflective enhancement film; then laminating in the laminator.

[0155] The rest is the same as in Example 1.

[0156] The following tests were performed on Examples 1-3 and Comparative Examples 1-5:

[0157] Reflectivity is tested according to IEC62788-2-1, with a test band of 330-1100nm (distinguishing between 330-380nm and 380-1100nm tests);

[0158] The method for testing the adhesion between the buffer layer and the battery is as follows: cut the sample into strips 1cm wide, and place them into the laminator in the order of glass / encapsulation film / battery / enhancing film from bottom to top for lamination. The lamination temperature is 120℃ for the first cavity and 140℃ for the second cavity, and the lamination time is 18min. After lamination, the peel strength between the buffer layer and the battery is tested using a tensile testing machine.

[0159] The method for testing the adhesion between the substrate layer and the adhesive film is as follows: cut the sample into strips 1cm wide, stack them in the order of reflective enhancement film (substrate layer with adhesive film) / release paper / adhesive film / glass, and put them into a laminator for lamination. The lamination temperature is 120℃ for the first chamber and 140℃ for the second chamber, and the lamination time is 18min. After lamination, the peel strength between the substrate layer and the adhesive film is tested using a tensile testing machine.

[0160] The test results are shown in Table 1.

[0161] Table 1

[0162]

[0163]

[0164] The data in Table 1 shows that:

[0165] The reflectivity in the 330-380nm ultraviolet region of Examples 1-3 is all >50%, the adhesion between the buffer layer and the battery is all >32N / cm, the adhesion between the substrate layer and the adhesive film is all >33N / cm, the component power is all >577W, and the appearance is OK.

[0166] Comparing Example 1 with Comparative Examples 1-2, Comparative Example 1 contains no nanomaterials and Comparative Example 2 contains no mesoporous materials. The reflectance of Example 1 in the 330-380nm ultraviolet region is greater than that of Comparative Example 1 (30.65%) and Comparative Example 2 (15.42%). This indicates that only by combining mesoporous materials and nanomaterials can the reflectance in the 330-380nm ultraviolet region be improved. Using only mesoporous materials or nanomaterials cannot improve the reflectance in the 330-380nm ultraviolet region.

[0167] Compared with Comparative Examples 1-2, Comparative Example 1 did not contain nanomaterials and Comparative Example 2 did not contain mesoporous materials. The adhesion between the buffer layer and the battery and the substrate layer and the adhesive film in Example 1 were greater than those in Comparative Examples 1-2. This shows that only by combining mesoporous materials and nanomaterials can the adhesion between the buffer layer and the battery and the adhesion between the substrate layer and the adhesive film be improved. Using only mesoporous materials or nanomaterials cannot improve the adhesion between the buffer layer and the battery and the adhesion between the substrate layer and the adhesive film.

[0168] Comparing Example 1 with Comparative Examples 1-2, Comparative Example 1 has no nanomaterials and Comparative Example 2 has no mesoporous materials. The power of the components in Example 1 is greater than that in Comparative Examples 1-2. This shows that only by combining mesoporous materials and nanomaterials can the reflectivity in the ultraviolet region be improved, thereby improving the power generation of the components. Using only mesoporous materials or nanomaterials cannot improve the power generation of the components.

[0169] Compared with Comparative Example 3, Comparative Example 3 has no mesoporous composite material, so it has almost no reflectivity in the ultraviolet region of 330-380nm. This shows that only by combining mesoporous materials and nanomaterials can the reflectivity in the ultraviolet region of 330-380nm be improved.

[0170] The reflectance of Example 1 and Comparative Examples 1-3 in the visible and near-infrared regions of 380-1100nm is basically the same, indicating that the addition of mesoporous composite materials does not affect the reflectance in this wavelength range of 380-1100nm.

[0171] Compared with Comparative Example 4, Example 1 was found to have cracked due to the absence of a buffer layer. The battery power of Comparative Example 4 also decreased significantly compared with Example 1. This indicates that only by combining the buffer layer and the substrate layer can the desired reflective enhancement film and enhanced photovoltaic module be made.

[0172] Comparing Example 1 with Comparative Example 5, the power output of Example 1 when the reflective enhancement film is laid on the gap between the photovoltaic cells is higher than that of Comparative Example 5. This indicates that the placement of the reflective enhancement film affects the module power output, and laying the reflective enhancement film on the gap between the photovoltaic cells is better than laying it on the back glass.

[0173] Any parts or structures not specifically described in this invention can be made using existing technologies or products, and will not be elaborated upon here.

[0174] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A reflective enhancing film, characterized in that, It includes a buffer layer and a substrate layer. The raw materials for preparing the buffer layer include ethylene polymers, mesoporous composite materials, fillers, and additives. The raw materials for preparing the substrate layer include propylene polymer alloys, mesoporous composite materials, fillers, and additives. The buffer layer comprises the following components by weight: 55-93 parts of ethylene polymers 2-12 parts of mesoporous composite material 5-30 parts of filler Additives: 0.1-3 parts; The substrate layer comprises the following components in parts by weight: 57-90 parts of propylene polymer alloy 5-25 parts of mesoporous composite material 5-25 parts of filler Additives: 0.1-3 parts; The mesoporous composite material is formed by combining mesoporous material and nanomaterial. The mesoporous material is selected from at least one of MCM-41, SBA-15, and MCM-48, and the nanomaterial is selected from at least one of nano zinc oxide, nano calcium carbonate, and nano barium sulfate. The particle size of the nanomaterial is 10-200 nm. The propylene polymer alloy is an alloy of propylene polymer and ethylene polymer; The ethylene polymer has a melting point of 70-120℃ and a hardness of <80A, and is selected from one or more combinations of polyethylene, ethylene-octene copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, maleic anhydride-grafted ethylene-butene copolymer, maleic anhydride-grafted ethylene-octene copolymer, and maleic anhydride-grafted ethylene-hexene copolymer.

2. The reflective enhancement film according to claim 1, characterized in that, The thickness of the buffer layer is 30-100μm, and the thickness of the substrate layer is 20-100μm.

3. The reflective enhancement film according to claim 1, characterized in that, The propylene polymer is selected from one or more combinations of homopolymer polypropylene, copolymer polypropylene, and block polypropylene.

4. The reflective enhancement film according to claim 1, characterized in that, The filler is selected from one or more of titanium dioxide, calcium carbonate, talc, mica, barium sulfate, silicon dioxide, and glass microspheres.

5. The reflective enhancement film according to claim 1, characterized in that, The additives include antioxidants and light stabilizers, wherein the antioxidants are primary antioxidants or a mixture of primary and secondary antioxidants, and the light stabilizers are ultraviolet absorbers and / or ultraviolet stabilizers.

6. An efficiency-enhancing photovoltaic module, characterized in that, The reflective enhancement film includes any one of claims 1-5, wherein the reflective enhancement film is laid in the gap between the photovoltaic module cells and the lower encapsulation film.

Images