Solar cell and display device

Abstract

The utility model discloses a solar cell and a display device. The solar cell includes: a transparent substrate; the transparent front electrode is arranged on the surface of the transparent substrate; the photovoltaic layer is arranged on the surface of the transparent front electrode; the back electrode is arranged on the surface of the photovoltaic layer; the packaging rear cover is arranged on the surface of the back electrode, one side, adjacent to the back electrode, of the packaging rear cover is provided with a water-oxygen barrier glue layer, and the water-oxygen barrier glue layer covers the back electrode; and the insulating layer is arranged on the inner and outer edges of the transparent front electrode and the photovoltaic layer. By arranging the packaging rear cover and arranging the water-oxygen barrier glue layer on the packaging rear cover, the water-oxygen barrier glue layer covers the back electrode, so that water vapor and oxygen which enable the efficiency of the solar cell to rapidly decline can be isolated, and stable performance of the solar cell is ensured. Besides, the water-oxygen barrier adhesive layer and the packaging rear cover are integrated together, and the packaging rear cover can be made of ultrathin and light materials, so that the requirements of light weight and thinness of the solar cell device are met.

Description

Technical Field

[0001] The present application relates to the technical field of electronic products, and particularly to a solar cell and a display device. Background Art

[0002] At present, with the vigorous development of electronic technology, various portable electronic display devices and wearable electronic products have been widely used. Since most portable electronic products are equipped with relatively safe but small-capacity storage batteries, frequent wired charging is the only option to ensure high-frequency use of electronic products. In order to improve the battery life of electronic products as much as possible, some high-end portable electronic devices have been equipped with relatively lightweight external solar cells, in order to reduce the frequency of continuous charging and obtain sufficient safety protection even in emergency situations without a backup power source. Among them, amorphous silicon-based solar cells made of glass substrates have gained the favor of many terminal product designers due to their thin and light appearance. Although amorphous silicon solar cells are thin and light enough and are easy to be tightly assembled with the display, due to the limitations of device types, the power generation efficiency of amorphous silicon solar cells is relatively low (the photoelectric conversion efficiency under 1 Sun is about 7%), and at the same time, there is an S-W effect in such devices. After being irradiated by strong light for 100 hours, the efficiency of the device will irreversibly drop to about 5%. Given such limitations, such solar cells cannot bring unexpected surprises to consumers. With the rapid development of photovoltaic technology, the third-generation solar cells with higher photoelectric conversion efficiency (such as organic solar cells and perovskite-based solar cells) are ready to go and are becoming alternative products to amorphous silicon-based solar cells and gradually coming into people's view. The high efficiency of such new solar cells is their natural advantage, but the drawback is that most of the photovoltaic materials used in such solar cell devices are organic materials or organic-inorganic hybrid photovoltaic materials. Therefore, similar to the structure of OLED display devices, currently, such solar cells all need to use a packaging process to add a back cover packaging structure with a glass structure for them, as Figure 1 shown, to block water vapor and oxygen that cause their efficiency to decline rapidly and ensure their stable performance. Although such new solar cell devices have an absolute advantage in terms of performance, due to the limitations of their product structure, it is not easy to make thin and light products. Summary of the Invention

[0003] The present application provides a solar cell, a manufacturing method thereof, and a display device, which meet the overall design goal of thinning electronic products by optimizing the device structure of the solar cell.

[0004] The object of the present application is achieved through the following technical solutions:

[0005] One embodiment of the present application provides a solar cell, comprising:

[0006] A transparent substrate;

[0007] A transparent front electrode disposed on the surface of the transparent substrate;

[0008] A photovoltaic layer disposed on the surface of the transparent front electrode;

[0009] A back electrode disposed on the surface of the photovoltaic layer; and

[0010] A packaging back cover disposed on the surface of the back electrode, a water and oxygen barrier adhesive layer is disposed on one side of the packaging back cover adjacent to the back electrode, and the water and oxygen barrier adhesive layer covers the back electrode;

[0011] An insulating layer disposed on the inner and outer edges of the transparent front electrode and the photovoltaic layer.

[0012] In one embodiment, the water and oxygen barrier adhesive layer is composed of an organic material film layer or an inorganic material film layer; or, the water and oxygen barrier adhesive layer is formed by overlapping an organic material film layer and an inorganic material film layer. Or, the water and oxygen barrier adhesive layer is formed by mixing an organic material and an inorganic material in a certain proportion.

[0013] In one embodiment, the photovoltaic layer includes a hole transport layer, a photovoltaic active layer, and an electron transport layer disposed in sequence, and the cross-sectional width of the photovoltaic layer in the vertical direction is greater than the cross-sectional widths of the transparent front electrode and the back electrode in the vertical direction.

[0014] In one embodiment, the cross-sectional width of the transparent front electrode in the vertical direction is greater than or equal to the cross-sectional width of the back electrode in the vertical direction.

[0015] In one embodiment, the difference between the cross-sectional width of the back electrode in the vertical direction and the cross-sectional width of the transparent front electrode in the vertical direction is between 0 μm and 200 μm.

[0016] In one embodiment, the difference between the cross-sectional widths of the hole transport layer and the electron transport layer in the vertical direction and the cross-sectional width of the transparent front electrode in the vertical direction is more than 3 μm.

[0017] In one embodiment, the difference between the cross-sectional widths of the hole transport layer and the electron transport layer in the vertical direction and the cross-sectional width of the transparent front electrode in the vertical direction is between 5 μm and 200 μm.

[0018] In one embodiment, the cross-sectional width of the photovoltaic active layer in the vertical direction is greater than the cross-sectional widths of the hole transport layer and the electron transport layer in the vertical direction.

[0019] In one embodiment, the difference between the cross-sectional width of the photovoltaic active layer in the vertical direction and the cross-sectional widths of the hole transport layer and the electron transport layer in the vertical direction is 3 μm or more.

[0020] In one embodiment, the difference between the cross-sectional width of the photovoltaic active layer in the vertical direction and the cross-sectional widths of the hole transport layer and the electron transport layer in the vertical direction is between 5 μm and 300 μm.

[0021] In one embodiment, the solar cell includes a segmented region that divides the solar cell into at least two segments.

[0022] In the segmented region, the transparent front electrode is removed, such that the transparent front electrodes of each segment of the solar cell are physically separated from the transparent front electrodes of the adjacent solar cells;

[0023] In the segmented region, the back electrode is removed, such that the back electrodes of each segment of the solar cell are physically separated from the back electrodes of the adjacent solar cells;

[0024] In the segmented region, the photovoltaic layer is retained, such that the photovoltaic layers of each segment of the solar cell are physically connected to the photovoltaic layers of the adjacent solar cells.

[0025] In one embodiment, the solar cell further includes a passivation film disposed on the surface of the segmented region of the back electrode or on the surface of the encapsulation back cover corresponding to the segmented region, and the passivation film completely covers the segmented region of the back electrode, or the passivation film completely covers the back electrode.

[0026] In one embodiment, when the passivation film is made of a light-transmissive material, the solar cell further includes a metal layer, the size of the metal layer is smaller than the size of the passivation film, and the metal layer completely covers the gap of the segmented region.

[0027] In one embodiment, when the passivation film is made of a light-impermeable material, the material for making the passivation film is selected from one or more of dark inks, insulating blackened metals, or dark tapes or adhesives.

[0028] In one embodiment, a colorless transparent insulating layer is further provided at the inner and outer edges between the transparent front electrode of the solar cell and the photovoltaic layer. When the solar cell includes a segmented region, the colorless transparent insulating layer also covers the region where the segmented region is located.

[0029] In one embodiment, the colorless transparent insulating layer includes a first insulating layer and a second insulating layer. The first insulating layer is disposed at the inner edge between the transparent front electrode and the photovoltaic layer, and the second insulating layer is disposed at the outer edge between the transparent front electrode and the photovoltaic layer.

[0030] In one embodiment, the inner edge dimension of the first insulating layer is set to be expanded by more than 3 μm compared with the inner edge dimension of the transparent front electrode, and the inner edge dimension of the first insulating layer is set to be shrunk by more than 5 μm compared with the inner edge dimension of the back electrode.

[0031] The outer edge dimension of the second insulating layer is set to be expanded by more than 5 μm compared with the outer edge dimension of the transparent front electrode, and the inner edge dimension of the second insulating layer is set to be shrunk by more than 3 μm compared with the outer edge dimension of the back electrode.

[0032] In one embodiment, the material of the colorless transparent insulating layer includes:

[0033] An inorganic insulating thin film of transparent material, with the thickness range set between 10 nm and 2 μm.

[0034] An organic polymer thin film, with the thickness range set between 100 nm and 5 μm.

[0035] In one embodiment, the solar cell further includes an ultra-thin metal film layer. The thickness of the ultra-thin metal film layer is less than 5 nm, and the ultra-thin metal film layer is disposed inside the electron transport layer, or inside the hole transport layer, or simultaneously inside the hole transport layer and the electron transport layer.

[0036] In one embodiment, the thickness of the ultra-thin metal film layer is between 0.5 nm and 3 nm.

[0037] In one embodiment, there is at least a hole transport layer or an electron transport layer with a thickness of more than 5 nm between the ultra-thin metal film layer and the photovoltaic active layer.

[0038] In one embodiment, the solar cell further includes a passivation layer. The passivation layer is disposed between the back electrode and the encapsulation back cover to prevent the back electrode from reacting with the water and oxygen barrier adhesive layer.

[0039] In one embodiment, the passivation layer is an inorganic metal oxide layer, and the film thickness of the inorganic metal oxide layer is between 3 nm and 2000 nm.

[0040] In one embodiment, the encapsulation rear cover is made of UTG or a transparent polymer film material, and the polymer is selected from one or more of PEN, PET, PC, PI, COP, and TAC materials.

[0041] In one embodiment, the solar cell includes a photovoltaic region and a colorless transparent region. The photovoltaic region is disposed around the colorless transparent region, and the colorless transparent region is a hollow structure.

[0042] In one embodiment, the hollow structure extends from the transparent front electrode to the back electrode;

[0043] Alternatively, the hollow structure extends from the transparent front electrode to the encapsulation rear cover.

[0044] In one embodiment, the types of the solar cells include organic solar cells, perovskite solar cells, dye-sensitized solar cells, and antimony sulfide solar cells.

[0045] One embodiment of the present application further provides a method for manufacturing a solar cell, including the following steps:

[0046] Provide a transparent substrate;

[0047] Dispose a transparent front electrode on the surface of the transparent substrate;

[0048] Dispose a photovoltaic layer on the surface of the transparent front electrode;

[0049] Dispose a back electrode layer on the surface of the photovoltaic layer;

[0050] Dispose an encapsulation rear cover on the surface of the back electrode. A water and oxygen barrier adhesive layer is disposed on a side of the encapsulation rear cover adjacent to the back electrode, and the water and oxygen barrier adhesive layer covers the back electrode; and

[0051] Dispose insulating layers on the inner and outer edges of the transparent front electrode and the photovoltaic layer.

[0052] One embodiment of the present application further provides a display device, including a display and the solar cell according to any one of the above embodiments. The solar cell is disposed on a side of the display close to the user, and the graphics of the display pass through the solar cell and are presented to the user.

[0053] Compared with the prior art, the solar cell provided by the present application has the following advantages and beneficial effects:

[0054] In the solar cell provided by the present application, by providing a packaging back cover and arranging a water and oxygen barrier adhesive layer on the packaging back cover, since the water and oxygen barrier adhesive layer covers the back electrode, it can isolate water vapor and oxygen that cause the rapid decline of the efficiency of the solar cell and ensure its stable performance. In addition, since the water and oxygen barrier adhesive layer and the packaging back cover are integrated together, the packaging back cover can be made of ultra-thin and lightweight materials, thereby meeting the requirements of the thin and light of the solar cell device. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 is a schematic structural diagram of a prior art solar cell;

[0056] Figure 2 is a schematic structural diagram of a solar cell provided by one embodiment of the present application;

[0057] Figure 3 is Figure 2 a top view schematic diagram when the solar cell in

[0058] Figure 4 is Figure 2 a top view schematic diagram when the solar cell in

[0059] Figure 5 is Figure 2 a specific structural schematic diagram of the photovoltaic layer of the solar cell in

[0060] Figure 6 is Figure 3 a cross-sectional schematic diagram of the solar cell in

[0061] Figure 7 is Figure 4 a cross-sectional schematic diagram of the solar cell in

[0062] Figure 8 a schematic structural diagram of a solar cell with an insulating film;

[0063] Figure 9 a schematic structural diagram of a solar cell with an opaque insulating film;

[0064] Figure 10 a schematic structural diagram of a solar cell with an opaque insulating film provided by another embodiment;

[0065] Figure 11 a schematic structural diagram of a solar cell with an opaque insulating film provided by still another embodiment;

[0066] Figure 12 a schematic structural diagram of the display provided by one embodiment of the present application;

[0067] Figure 13 Schematic structural diagram of the display provided by another embodiment of the present application;

[0068] Figure 14 Schematic structural diagram of the display provided by yet another embodiment of the present application. Detailed implementation manners

[0069] The present application will be further described in detail below in conjunction with embodiments, but the implementation manners of the present application are not limited thereto.

[0070] Please refer to Figure 2 , one embodiment of the present application provides a solar cell 100. The solar cell 100 includes:

[0071] A transparent substrate 110;

[0072] A transparent front electrode 120, disposed on the surface of the transparent substrate 110;

[0073] A photovoltaic layer 130, disposed on the surface of the transparent front electrode 120;

[0074] A back electrode 140, disposed on the surface of the photovoltaic layer 130;

[0075] A packaging rear cover 150, disposed on the surface of the back electrode 140. A water and oxygen barrier adhesive layer 160 is disposed on one side of the packaging rear cover 150 adjacent to the back electrode 140. The water and oxygen barrier adhesive layer 160 covers the back electrode 140; and

[0076] An insulating layer 190, disposed on the inner and outer edges of the transparent front electrode 120 and the photovoltaic layer 130.

[0077] In the solar cell 100 provided by the present application, by providing the packaging rear cover 150 and disposing the water and oxygen barrier adhesive layer 160 on the packaging rear cover 150, since the water and oxygen barrier adhesive layer 160 covers the back electrode 140, it can isolate water vapor and oxygen that cause the efficiency of the solar cell to decline rapidly and ensure its stable performance. In addition, since the water and oxygen barrier adhesive layer 160 and the packaging rear cover 150 are integrated together, the packaging rear cover 150 can be made of ultra-thin and lightweight materials, thereby meeting the requirements of the solar cell device for being thin and light. In this embodiment, the types of the solar cell 100 include organic solar cells, perovskite solar cells, dye-sensitized solar cells, and antimony sulfide solar cells. In one embodiment, the water and oxygen barrier adhesive layer 160 is composed of an organic material film layer or an inorganic material film layer; or, the water and oxygen barrier adhesive layer 160 is formed by overlapping an organic material film layer and an inorganic material film layer.

[0078] Please refer to together Figure 3, in this embodiment, the solar cell 100 is a single - cell device. The solar cell 100 includes a colorless transparent region 10 and a photovoltaic power generation region 20 surrounding the colorless transparent region 10. The photovoltaic power generation region 20 can be either semi - transparent or opaque. The colorless transparent region 10 is used to present an image disposed below the solar cell 100.

[0079] Please refer to Figure 4 , in this embodiment, the solar cell 100 can also be a multi - cell device. The solar cell 100 includes a colorless transparent region 10 and a photovoltaic power generation region 20 surrounding the colorless transparent region 10. The photovoltaic power generation region 20 can be either semi - transparent or opaque. The colorless transparent region 10 is used to present an image disposed below the solar cell 100. In this embodiment, the solar cell 100 further includes a sectioning region 30. The sectioning region 30 divides the photovoltaic power generation region 20 into multiple solar cells.

[0080] The transparent substrate 110 includes, but is not limited to, rigid materials such as glass, quartz, sapphire, etc., or flexible transparent organic polymer materials such as PET (polyethylene terephthalate), CPI (transparent polyimide), PEN (polyethylene naphthalate), COP (cycloolefin polymer), PC (polycarbonate), PMMA (polymethyl methacrylate). According to needs, the transparent substrate 110 can also be made of the above materials as the base, and a single - layer film or multi - layer film with a water - oxygen barrier function is made on the surface of this base. The single - layer or multi - layer water - oxygen barrier film is made of inorganic materials or organic materials. The single - layer or multi - layer water - oxygen barrier film can be made of inorganic materials or organic materials alone, or can be formed by overlapping organic films and inorganic films. The water - vapor barrier effect of the water - oxygen barrier film is evaluated by the WVTR value, and the WVTR range is between 1E -2 -1E -6 g / (m 2 ·day). According to needs, one surface or the upper and lower two surfaces of the transparent substrate 110 also include an anti - reflection layer made of inorganic or organic materials, so as to reduce the reflectivity of incident light on the upper and lower two surfaces of the substrate and improve the utilization rate of incident light.

[0081] The transparent front electrode 120 is made of graphene, metal oxide (ITO (indium tin oxide), AZO (indium zinc oxide), FTO (fluorine-doped tin dioxide), ATO (tin antimony oxide), etc.), nanosilver, metal single substance or alloy (magnesium, silver single substance or alloy), high conductivity organic polymer material (such as PEDOT:PSS, polybenzodifurandione), etc. Preferably, the transparent front electrode 120 can also be matched with a metal auxiliary electrode (silver, aluminum, molybdenum, copper, titanium, chromium, etc., a metal single substance or alloy with low resistivity) to improve the conductivity of the transparent front electrode 120, thereby improving the photoelectric conversion efficiency of the device.

[0082] The back electrode 140 is made of graphene, metal oxide, nanosilver, organic polymer materials with high conductivity, metal single substance or alloy materials. Furthermore, the back electrode can be made by selecting appropriate materials and thickness according to the transmission type (transparent or opaque) of the device. When the device is designed as a colored transparent type solar cell, graphene, metal oxide (ITO, AZO, FTO, ATO, etc.), nanosilver, or organic polymer materials with high conductivity (such as PEDOT:PSS, polybenzodifurandione) are preferably used as the back electrode 140, and its thickness range is set within the range of 20nm-5μm. Further, when an ultra-thin metal single substance or alloy material is selected as the back electrode material, its thickness needs to be set within the range of 10-30nm. When the device is designed as a colored opaque type solar cell, a metal single substance or alloy material is preferably used as the back electrode 140, and its thickness needs to be set within the range of 100nm-300nm.

[0083] Please also see Figure 5 In one embodiment, the photovoltaic layer 130 includes a hole transport layer 131, a photovoltaic active layer 132 and an electron transport layer 133 arranged in sequence. In this embodiment, the solar cell 100 also includes an ultra-thin metal film layer 134. The thickness of the ultra-thin metal film layer 134 is less than 5nm. The ultra-thin metal film layer 134 is arranged inside the electron transport layer 133, or inside the hole transport layer 131, or inside the hole transport layer 131 and the electron transport layer 133 at the same time. Preferably, the thickness of the ultra-thin metal film layer is between 0.5nm and 3nm.

[0084] In one embodiment, the ultra-thin metal film layer 134 and the photovoltaic active layer 132 are separated by a hole transport layer 131 or an electron transport layer 133 with a thickness of more than 5 nm.

[0085] In this embodiment, the PV photovoltaic layer has a basic structure consisting of a hole transport layer (HTL), a photovoltaic active layer (ACT-L), and an electron transport layer (ETL). The PV photovoltaic layer can be a p-type device or an n-type device. The hole transport layer 131 or the electron transport layer 133 further includes an ultra-thin metal (Au, Ag, Pt, Al, Cr, Ti, Mo) film layer sandwiched therein. The thickness of the metal film layer is less than 5 nm. Preferably, the thickness of the metal film layer is 0.5 nm to 3 nm. The ultra-thin metal film layer 134 is spaced from the photovoltaic active layer 132 by at least 5 nm or more of the hole transport layer or the electron transport layer. The ultra-thin metal film layer 134 can be disposed only in the hole transport layer or the electron transport layer, or can be disposed in both the hole transport layer and the electron transport layer simultaneously, for reducing the reflection of light by the photovoltaic layer, improving the light absorption of the solar cell, and thereby improving the efficiency of the solar cell device.

[0086] Please also refer to Figure 6 , in one embodiment, the cross-sectional width of the photovoltaic layer 130 in the vertical direction is greater than the cross-sectional widths of the transparent front electrode 120 and the back electrode 140 in the vertical direction. The cross-sectional width of the transparent front electrode 120 in the vertical direction is greater than or equal to the cross-sectional width of the back electrode 140 in the vertical direction. Specifically, the difference between the cross-sectional width of the back electrode 140 in the vertical direction and the cross-sectional width of the transparent front electrode 120 in the vertical direction is between 0 μm and 200 μm.

[0087] In one embodiment, the difference between the cross-sectional widths of the hole transport layer 131 and the electron transport layer 133 in the vertical direction and the cross-sectional width of the transparent front electrode 120 in the vertical direction is 3 μm or more. Preferably, the difference between the cross-sectional widths of the hole transport layer 131 and the electron transport layer 133 in the vertical direction and the cross-sectional width of the transparent front electrode 120 in the vertical direction is between 5 μm and 200 μm.

[0088] In one embodiment, the cross-sectional width of the photovoltaic active layer 132 in the vertical direction is greater than the cross-sectional widths of the hole transport layer 131 and the electron transport layer 133 in the vertical direction. Specifically, the difference between the cross-sectional width of the photovoltaic active layer 132 in the vertical direction and the cross-sectional widths of the hole transport layer 131 and the electron transport layer 133 in the vertical direction is 3 μm or more. Preferably, the difference between the cross-sectional width of the photovoltaic active layer in the vertical direction and the cross-sectional widths of the hole transport layer and the electron transport layer in the vertical direction is between 5 μm and 300 μm.

[0089] That is, the basic structure of the solar cell 100 is a transparent front electrode 120, a photovoltaic layer 130, and a back electrode 140 sequentially disposed on a transparent substrate 110. The photovoltaic layer includes a hole transport layer 131, a photovoltaic active layer 132, and an electron transport layer 133. The stacking of the hole transport layer 131, the photovoltaic active layer 132, and the electron transport layer 133 is set according to the following rules:

[0090] The outer dimensions L3 of the hole transport layer 131 and the electron transport layer 133 are set to extend outward by more than 3 μm on each side compared with the outer dimensions L2 of the adjacent transparent front electrode 120 and the outer dimensions L1 of the back electrode 140. The preferred range of the outward extension dimension is 5 - 200 μm.

[0091] The outer dimensions L4 of the photovoltaic active layer 132 are set to extend outward by more than 3 μm on each side compared with the outer dimensions L3 of the adjacent hole transport layer 131 and the electron transport layer 133. The preferred range of the outward extension dimension is 5 - 300 μm.

[0092] The outer dimensions L1 of the back electrode 140 are compared with the outer dimensions L2 of the transparent front electrode 120. The back electrode 140 is set to be retracted or extended relative to the transparent front electrode 120. The preferred range of the retraction or extension dimension is 0 μm to 150 μm.

[0093] The completely overlapping part of the transparent front electrode 120, the photovoltaic layer 130, and the back electrode 140 is the effective photovoltaic power generation area of the solar cell.

[0094] According to needs, the solar cell 100 further includes a transparent insulating layer 190. The colorless transparent insulating layer 190 is disposed on the inner and outer edges of the transparent front electrode 120 and the photovoltaic layer 130.

[0095] Please refer to Figure 6 , the colorless transparent insulating layer 190 includes a first insulating layer 191 and a second insulating layer 192. The first insulating layer 191 is disposed on the inner edge of the transparent front electrode 120 and the photovoltaic layer 130. The second insulating layer 192 is disposed on the outer edge of the transparent front electrode 120 and the photovoltaic layer 130. The inner edge dimension of the first insulating layer 191 is set to extend outward by more than 3 μm compared with the inner edge dimension of the transparent front electrode 120. The outer edge dimension of the first insulating layer 191 is set to be retracted by more than 5 μm compared with the inner edge dimension of the back electrode 140. The outer edge dimension of the second insulating layer 192 is set to extend outward by more than 5 μm compared with the outer edge dimension of the transparent front electrode 120. The inner edge dimension of the second insulating layer 192 is set to be retracted by more than 3 μm compared with the outer edge dimension of the back electrode 140.

[0096] In this embodiment, the material of the colorless and transparent insulating layer 190 includes:

[0097] An inorganic insulating thin film of a transparent material, with a thickness range set between 10 nm and 2 μm;

[0098] An organic polymer thin film, with a thickness range set between 100 nm and 5 μm.

[0099] Specifically, in a single-junction solar cell, a first insulating layer 191 is further provided in the inner edge region of the photovoltaic layer 130 and the transparent front electrode 120. The outer dimension of the first insulating layer 191 is set to be expanded by more than 3 μm compared with the inner edge dimension of the adjacent transparent front electrode 120. Preferably, the outer dimension of the first insulating layer 191 is set to be expanded by 5 - 300 μm compared with the inner edge dimension of the adjacent transparent front electrode 120. In one embodiment, the first insulating layer covers the entire hollowed-out area 40 of the solar cell. The outer edge dimension of the first insulating layer 191 is set to be retracted by more than 5 μm compared with the edge (inner edge) of the back electrode 140 close to the colorless and transparent area 10. Preferably, the retracted dimension of the outer edge dimension of the first insulating layer 191 compared with the inner edge dimension of the back electrode 140 is set to be 5 - 300 μm. In contrast, a second insulating layer 192 is provided in the outer edge region of the photovoltaic layer 130 and the transparent front electrode 120. The outer dimension of the second insulating layer 192 is set to be expanded by more than 5 μm compared with the outer edge dimension of the transparent front electrode 120. Preferably, the outer dimension of the second insulating layer 192 is set to be expanded by 5 - 300 μm compared with the outer edge dimension of the transparent front electrode 120. The dimension of the second insulating layer 192 close to the colorless and transparent area 10 is preferably set in the non-effective photovoltaic power generation area between the back electrode 140 and the auxiliary metal electrode in the vertical direction, or according to the actual process capabilities, the insulating layer can be extended into the transparent front electrode area inside the auxiliary metal. At this time, the effective photovoltaic power generation area will become smaller accordingly.

[0100] Please refer to Figure 6 , for a multi-junction cell provided with a segmented area, the design rules of the first insulating layer 191 and the second insulating layer 192 are as follows: The setting method of the first insulating layer 191 close to the hollowed-out colorless and transparent area 10 is the same as that of the single-junction cell. And for the setting of the second insulating layer 192 provided in the peripheral area of the multi-junction solar cell, it is preferably set in the area where the back electrode of the Nth segment extends outward. The extended back electrode 140 is electrically connected to the transparent front electrode 120 at the (N + 1)th segment, forming a multi-junction solar cell in a series form of front and back in the ineffective power generation area at the periphery of the device.

[0101] As needed, in a multi-junction solar cell, the colorless transparent insulating layer 190 also covers the area where the sectioning region is located. Please also refer to Figure 4 , in this embodiment, the colorless transparent insulating layer 190 further includes a third insulating layer 193, and the third insulating layer 193 covers the sectioning region 30.

[0102] The colorless transparent insulating layer 190 is preferably an inorganic thin film of a transparent material, such as an inorganic insulating film of silicon oxide, aluminum oxide, zirconium oxide, titanium oxide, silicon nitride, or silicon oxynitride, etc., and the thickness range is set between 10 nm and 2 μm. It is also possible to select a thin film made of an organic polymer material (such as modified acrylic resin, phenolic resin, COP resin, etc.), and the thickness range is set between 100 nm and 5 μm. And according to the design rules, the required insulating pattern is made of the thin film by using an etching process.

[0103] Compared with the size of the transparent front electrode 120, the purpose of setting the size of the back electrode 140 to be retracted, setting the hole transport layer 131, the photovoltaic active layer 132, and the electron transport layer 133 to be expanded, and setting the colorless transparent insulating layer 190 between the transparent front electrode 120 and the photovoltaic layer 130 is to effectively increase the parallel resistance R of the device sh , and further increase the V of the device oc voltage. At the same time, the fill factor of the device can also be improved synchronously. According to the calculation formula of the photoelectric conversion efficiency of the solar cell: Eff = V oc *J sc *FF, when any one of the two factors of V oc and FF is improved, the efficiency of the device will be improved as a whole.

[0104] For a single-junction device, generally, the area of the photovoltaic layer 130 is set to be larger than the outer dimension of the back electrode 140. For a multi-junction cell, since it is impossible to set micron-level vias with high density and small aperture in the area of the photovoltaic layer 130, and the transparent front electrode 120 and the back electrode 140 between adjacent two cells must be physically separated, and it is even more impossible to set obvious visible metal traces or too large photovoltaic ineffective areas in the visible area of the solar cell. Therefore, usually, only the outermost overlapping area 11 of the device is used to connect the positive and negative electrodes of adjacent two cells in series by means of an auxiliary metal electrode 12 (please also refer to Figure 4 and Figure 6 ). In this way, it is very easy to see the sectioning region formed by the transparent front electrode 120 and the back electrode 140. Even if the distance between the sectioning regions is reduced to less than 10 μm, for the appearance of the product, the sectioning gaps formed by the sectioning regions are still visible.

[0105] To improve this problem, when the solar cell 100 is a multi-junction device, its structure can be improved. Please also refer to Figure 7 , in one embodiment, the solar cell 100 includes a segmentation region 30. The segmentation region 30 divides the solar cell 100 into at least two segments.

[0106] In the segmentation region 30, the transparent front electrode 120 is removed, so that the transparent front electrode 120 of each segment of the solar cell 100 is physically separated from the transparent front electrode 120 of the adjacent solar cell 100.

[0107] In the segmentation region 30, the back electrode 140 is removed, so that the back electrode 140 of each segment of the solar cell 100 is physically separated from the back electrode 140 of the adjacent solar cell 100.

[0108] In the segmentation region 30, the photovoltaic layer 130 is retained, so that the photovoltaic layer 130 of each segment of the solar cell 100 is physically connected to the photovoltaic layer 130 of the adjacent solar cell 100.

[0109] In this embodiment, for the gap in the segmentation region of the multi-junction cell, a design method of retaining the photovoltaic layer 130 (hole transport layer 131, photovoltaic active layer 132, and electron transport layer 133) to fill it is adopted. There are two purposes for adopting this design:

[0110] One is to avoid the situation that during the manufacturing process of the device, the evaporation mold of the back electrode 140 is offset and contacts the transparent front electrode 120, resulting in a short circuit;

[0111] The second is that when the photovoltaic layer 130 in this region is retained, in the case of further device design or structure optimization, the appearance difference in the segmentation region can be better eliminated and reach a level that is easily acceptable to customers.

[0112] Please also refer to Figure 8 , in one embodiment, the solar cell 100 further includes a passivation film 170. The passivation film 170 is disposed on the surface of the segmentation region of the back electrode 140 or the corresponding segmentation region of the encapsulation back cover 150. The passivation film 170 completely covers the segmentation region 30 of the back electrode 140, or the passivation film 170 completely covers the back electrode 140.

[0113] Specifically, when the passivation film 170 is made of a light-transmitting material, the solar cell 100 further includes a metal layer 171. The size of the metal layer 171 is smaller than the size of the passivation film 170, and the metal layer 170 completely covers the gap of the segmentation region 30.

[0114] When the passivation film 170 is made of a light-blocking material, the material for making the passivation film 170 is selected from one or more of dark inks, insulated blackened metals, or dark tapes or adhesives.

[0115] When observing the light-incident surface of the solar cell product under low light, although the segmented regions filled with the photovoltaic layer 130 are no longer so obvious, they can still be easily observed by reflection under strong light or when there is strong light emitted from below the solar cell. To further improve this problem, in this embodiment, at least one layer of passivation film 170 is provided in the segmented region on one side of the back electrode 140 of the multi-junction solar cell 100. The passivation film 170 completely covers the segmented region or completely covers the entire back electrode 140. According to the transmission type of the back electrode 140 of the solar cell 100, the passivation film 170 can be set to different types. For example, when the back electrode 140 is an opaque metal material, the passivation film 170 can be set to be either light-transmitting or light-blocking. When the passivation film 170 is a light-transmitting material (such as Al2O3), a metal layer 171 with a size smaller than the passivation film 170 but capable of completely covering the gaps in the segmented region is further provided on the surface of the passivation film 170. The thickness of the metal layer 171 is greater than 50 nm, and the transmittance in the visible light range is less than 5%. When the passivation film 170 is a light-blocking material, such as Figure 9 as shown, it can be one or more of dark inks, insulated blackened metals, or dark tapes or adhesives. Further, the light-blocking metal film 171 or the passivation film 170 can also be provided on the surface of the encapsulation back cover 150 corresponding to the segmented region.

[0116] Please refer to Figure 10 simultaneously. In one embodiment, the passivation film 170 is provided on the surface of the encapsulation back cover 150. At the same time, the passivation film 170 completely covers the region where the segmented region 30 is located.

[0117] Please refer to Figure 11 simultaneously. In one embodiment, the passivation film 170 is provided between the encapsulation back cover 150 and the water and oxygen barrier adhesive layer 160. Similarly, the passivation film 170 completely covers the region where the segmented region 30 is located.

[0118] The manufacturing method of the passivation film 170 is as follows:

[0119] After the production of the back electrode 140 is completed, an insulating oxide (such as MoO XOr Al2O3), a metal film with a reflectivity similar to that of the back electrode 140 is further deposited on the surface of the insulating oxide layer. For example, a metal such as aluminum, silver, copper, chromium, molybdenum, or gold with a thickness greater than 50 nm is deposited by evaporation. The size of the evaporated metal film needs to completely cover the segmented area but not exceed the outer dimensions of the insulating oxide on the surface of the back electrode to avoid short - circuits between adjacent two - cell batteries. When using Al - PET and Barrier PSA as the encapsulation back cover of the multi - junction solar cell, it is also possible not to additionally set a metal film or a passivation film, and directly use the back cover to shield the bottom - incident light, reducing the manufacturing difficulty of the device.

[0120] In one embodiment, the transparent substrate 110 is made of a flexible material such as colorless and transparent UTG, CPI, PEN, PC, TAC, or PET. The encapsulation back cover 150 directly adopts a TFE encapsulation type. Specifically, Si is fabricated by CVD process respectively x N y and a composite film structure of Al2O3, ZrO, TiO, or other inorganic metal oxides is deposited by atomic layer deposition (ALD) process to form a TFE thin - film encapsulation layer. Among them, the single - film layer thickness of metal oxides such as Al2O3 fabricated by the ALD process is ≥0.5 nm, and the single - film layer thickness of Si x N y is ≥50 nm. The total thickness of the TFE encapsulation layer is 200 nm - 2000 nm, and the TFE encapsulation film layer at this thickness is a colorless and transparent thin film. Further, the structure of the TFE encapsulation layer can be set to only cover the photovoltaic region 130, or can be set to cover all regions outside the electrode lead - out terminals.

[0121] One embodiment of the present application further provides a display device, including a display and the solar cell as described in any one of the above embodiments. Specifically, in the display device, the solar cell is disposed on the surface of the display device near the user side. The image of the display passes through the solar cell and is presented to the user. In one embodiment, the image of the display is presented to the user through the hollowed - out area provided in the solar cell.

[0122] Please refer to Figure 12 , in one embodiment, the display device 200 includes a display 210 and a solar cell 100 disposed on the display 210. The display 210 and the solar cell 100 are bonded by an optical adhesive 220. The part of the 220 corresponding to the displayed image can be set in a hollowed - out form corresponding to the size of the hollowed - out area 40 of the solar cell, or can be set in a non - hollowed - out whole - surface form.

[0123] In this embodiment, the solar cell 100 includes:

[0124] A transparent substrate 110;

[0125] A transparent front electrode 120, disposed on the surface of the transparent substrate 110;

[0126] A photovoltaic layer 130, disposed on the surface of the transparent front electrode 120;

[0127] A back electrode 140, disposed on the surface of the photovoltaic layer 130; and

[0128] A packaging rear cover 150, disposed on the surface of the back electrode 140. A water and oxygen barrier adhesive layer 160 is disposed on a side of the packaging rear cover 150 adjacent to the back electrode 140. The water and oxygen barrier adhesive layer 160 covers the back electrode 140.

[0129] Optionally, the solar cell 100 further includes a colorless transparent insulating layer 190. The colorless transparent insulating layer 190 is disposed at the inner and outer edges of the transparent front electrode 120 and the photovoltaic layer 130.

[0130] The solar cell 100 further includes a hollowed-out area 40. An image of the display 210 is presented to a user through the hollowed-out area 40 provided in the solar cell 100. In this embodiment, the hollowed-out area 40 extends from the transparent front electrode 120 to the packaging rear cover 150.

[0131] Optionally, the solar cell 100 further includes a layer of isolation layer 180. The isolation layer 180 is disposed between the back electrode 140 and the packaging rear cover 150 to prevent the back electrode 140 from reacting with the water and oxygen barrier adhesive layer 160. Specifically, the isolation layer 180 is an organic or inorganic compound, and the thickness of the organic or inorganic compound film layer is between 50 nm and 2000 nm.

[0132] In this embodiment, the packaging rear cover 150 is made of UTG or a transparent polymer film material, and the polymer is selected from one or more of PEN, PET, PC, PI, COP, and TAC materials.

[0133] In this embodiment, the solar cell 100 includes a photovoltaic region and a colorless transparent region, the photovoltaic region is disposed around the colorless transparent region, and the colorless transparent region is the hollowed-out area 40.

[0134] In this embodiment, the transparent substrate 110 is made of rigid materials such as glass and quartz. When the photovoltaic region 130 of the solar cell 100 is transparent or opaque, the encapsulation back cover 150 of the solar cell 100 is composed of UTG or a transparent polymer film material and a transparent adhesive with the ability to adsorb water and oxygen. The polymer is preferably made of PEN, PET, PC, PI, COP, or TAC materials, and can be either a single-layer film structure or a composite film structure. Between the composite films, a transparent adhesive or OCA with water and oxygen adsorption functions is preferably used for bonding. The transparent encapsulation back cover 150 can either entirely cover the photovoltaic region of the solar cell 100 and the colorless transparent region surrounded by it, or be configured such that the colorless transparent region of the solar cell is a hollow structure. Preferably, at least one organic or inorganic isolation layer 180 is provided between the encapsulation back cover 150 and the back electrode 140 to prevent physical or chemical reactions between the adsorbent or adhesive of the back cover and the back electrode 140. At the same time, when the back electrode 140 is a transparent material, this isolation layer 180 also has the function of reflecting incident light, thereby improving the absorption and reuse of light by the photovoltaic layer 130.

[0135] As needed, the setting of the hollow region 40 is not limited to the above embodiments.

[0136] Please refer to Figure 13 , in this embodiment, the display device 300 includes a display 310 and a solar cell 100 disposed on the display 310. The display 310 and the solar cell 100 are bonded together by an optical adhesive 320.

[0137] In this embodiment, the solar cell 100 includes:

[0138] A transparent substrate 110;

[0139] A transparent front electrode 120 disposed on the surface of the transparent substrate 110;

[0140] A photovoltaic layer 130 disposed on the surface of the transparent front electrode 120;

[0141] A back electrode 140 disposed on the surface of the photovoltaic layer 130; and

[0142] An encapsulation back cover 150 disposed on the surface of the back electrode 140. A water and oxygen barrier adhesive layer 160 is provided on the side of the encapsulation back cover 150 adjacent to the back electrode 140. The water and oxygen barrier adhesive layer 160 covers the back electrode 140.

[0143] As needed, the solar cell 100 further includes a colorless transparent insulating layer 190. The colorless transparent insulating layer 190 is disposed at the inner and outer edges of the transparent front electrode 120 and the photovoltaic layer 130.

[0144] The solar cell 100 further includes a hollowed-out area 40. The image of the display 310 is presented to the user through the hollowed-out area 40 provided on the solar cell 100. In this embodiment, the hollowed-out structure 40 extends from the transparent front electrode 120 to the back electrode 140.

[0145] In this embodiment, the transparent substrate 110 is made of rigid materials such as glass and quartz, and the encapsulation back cover 150 is made of glass or a transparent organic polymer (PEN, PET, PC, PI, COP, TAC) film. After the back electrode is completed, a liquid adhesive with a water and oxygen adsorption function is printed or coated on the surface of the back electrode side of the substrate or on the side where the back cover is attached to the substrate. After the substrate and the back cover are attached, the adhesive is then UV-cured or thermally cured. Preferably, at least one organic or inorganic isolation layer 180 is provided between the encapsulation back cover 150 and the back electrode 140 to prevent the adsorbent or adhesive of the encapsulation back cover 150 from reacting with the back electrode 140.

[0146] As needed, the structure of the solar cell 100 is not limited to the above embodiments. Please also refer to Figure 14 In this embodiment, the display device 400 includes a display 410 and a solar cell 100 disposed on the display 410. The display 410 and the solar cell 100 are bonded together by an optical adhesive 420.

[0147] In this embodiment, the solar cell 100 includes:

[0148] A transparent substrate 110;

[0149] A transparent front electrode 120 disposed on the surface of the transparent substrate 110;

[0150] A photovoltaic layer 130 disposed on the surface of the transparent front electrode 120;

[0151] A back electrode 140 disposed on the surface of the photovoltaic layer 130; and

[0152] An encapsulation back cover 150 disposed on the surface of the back electrode 140.

[0153] A colorless transparent insulating layer 190 disposed at the inner and outer edges of the transparent front electrode 120 and the photovoltaic layer 130.

[0154] In this embodiment, the transparent substrate 110 is made of a flexible material such as colorless and transparent UTG, CPI, PEN, PC, TAC or PET, with a thickness greater than or equal to 5 μm. The encapsulation back cover 150 is encapsulated by aluminum foil and an adhesive capable of adsorbing water and oxygen. Further, the encapsulation material has a hollow structure, and the hollow area is used to present an image disposed under the solar cell. Preferably, at least one organic or inorganic isolation layer 180 is further provided between the encapsulation back cover 150 and the back electrode 140 to prevent the adsorbent or adhesive of the encapsulation back cover 150 from reacting with the back electrode 140.

[0155] One embodiment of the present application further provides a method for manufacturing a solar cell, including the following steps:

[0156] Provide a transparent substrate;

[0157] Set a transparent front electrode on the surface of the transparent substrate;

[0158] Set a photovoltaic layer on the surface of the transparent front electrode;

[0159] Set a back electrode layer on the surface of the photovoltaic layer;

[0160] Set an encapsulation back cover on the surface of the back electrode. A water and oxygen barrier adhesive layer is provided on one side of the encapsulation back cover adjacent to the back electrode, and the water and oxygen barrier adhesive layer covers the back electrode; and

[0161] Set insulating layers on the inner and outer edges of the transparent front electrode and the photovoltaic layer.

[0162] The above embodiments are preferred embodiments of the present application, but the embodiments of the present application are not limited by the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit and principle of the present application shall be equivalent replacement methods and are all included in the protection scope of the present application.

Claims

1. A solar cell, characterized in that: include: Transparent substrate; A transparent front electrode is arranged on the surface of the transparent substrate; A photovoltaic layer is arranged on the surface of the transparent front electrode; A back electrode, disposed on the surface of the photovoltaic layer; A packaging back cover is arranged on the surface of the back electrode, a water-oxygen barrier adhesive layer is arranged on one side of the packaging back cover adjacent to the back electrode, and the water-oxygen barrier adhesive layer covers the back electrode; as well as The insulating layer is arranged at the inner and outer edges of the transparent front electrode and the photovoltaic layer.

2. The solar cell according to claim 1, characterized in that The photovoltaic layer includes a hole transport layer, a photovoltaic active layer and an electron transport layer which are arranged in sequence. The cross-sectional width of the photovoltaic layer in the vertical direction is greater than the cross-sectional widths of the transparent front electrode and the back electrode in the vertical direction.

3. The solar cell according to claim 2, characterized in that: The difference between the cross-sectional widths of the hole transport layer and the electron transport layer in the vertical direction and the cross-sectional widths of the transparent front electrode and the back electrode in the vertical direction is between 5 μm and 200 μm.

4. The solar cell according to claim 2, characterized in that: The cross-sectional width of the photovoltaic active layer in the vertical direction is greater than the cross-sectional widths of the hole transport layer and the electron transport layer in the vertical direction.

5. The solar cell according to claim 2, characterized in that: The difference between the cross-sectional width of the photovoltaic active layer in the vertical direction and the cross-sectional widths of the hole transport layer and the electron transport layer in the vertical direction is between 5 μm and 300 μm.

6. The solar cell according to claim 2, characterized in that: The solar cell comprises a section region, wherein the section region divides the solar cell into at least two sections. In the segmented area, the transparent front electrode is removed, so that the transparent front electrode of each solar cell is physically separated from the transparent front electrode of the adjacent solar cell; In the segmented area, the back electrode is removed, so that the back electrode of each solar cell is physically separated from the back electrode of the adjacent solar cell; In the section area, the photovoltaic layer is retained so that the photovoltaic layer of each solar cell is physically connected to the photovoltaic layer of its adjacent solar cell.

7. The solar cell according to claim 6, characterized in that: The solar cell also includes a passivation film, which is arranged on the surface of the segmented area of ​​the back electrode or the segmented area corresponding to the packaging back cover, and the passivation film completely covers the segmented area of ​​the back electrode, or the passivation film completely covers the back electrode.

8. The solar cell according to claim 7, characterized in that: When the passivation film is made of a light-transmitting material, the solar cell further comprises a metal layer, the size of the metal layer is smaller than the size of the passivation film, and the metal layer completely covers the gaps in the segmented regions.

9. The solar cell according to claim 7, characterized in that: When the passivation film is made of an opaque material, the material of the passivation film is selected from one or more of dark ink, insulating blackened metal, or dark tape or adhesive.

10. The solar cell according to claim 1, characterized in that: The insulating layer also covers the area where the segmented area is located; The insulating layer comprises a first insulating layer and a second insulating layer, the first insulating layer is arranged at the inner edge of the transparent front electrode and the photovoltaic layer, and the second insulating layer is arranged at the outer edge of the transparent front electrode and the photovoltaic layer; The material of the insulating layer includes an inorganic insulating film or an organic polymer film of a transparent material. The thickness range of the inorganic insulating film of a transparent material is set between 10nm-2μm; the thickness range of the organic polymer film is set between 100nm-5μm.

11. The solar cell according to claim 10, characterized in that The inner edge size of the first insulating layer is set to be more than 3 μm larger than the inner edge size of the transparent front electrode, and the outer edge size of the first insulating layer is set to be more than 5 μm smaller than the inner edge size of the back electrode; The outer edge size of the second insulating layer is set to be more than 5 μm larger than the outer edge size of the transparent front electrode, and the inner edge size of the second insulating layer is set to be more than 3 μm smaller than the outer edge size of the back electrode.

12. The solar cell according to claim 2, characterized in that: The solar cell also includes an ultra-thin metal film layer, the thickness of the ultra-thin metal film layer is between 0.5nm and 3nm, the ultra-thin metal film layer is arranged inside the electron transport layer, or inside the hole transport layer, or inside the hole transport layer and the electron transport layer at the same time, and the ultra-thin metal film layer and the photovoltaic active layer are separated by a hole transport layer or an electron transport layer with a thickness of at least 5nm.

13. The solar cell according to any one of claims 1 to 12, characterized in that: The solar cell further comprises an isolation layer, which is arranged between the back electrode and the packaging back cover to prevent the back electrode from reacting with the water and oxygen barrier adhesive layer; the thickness of the isolation layer is between 50nm and 2000nm.

14. The solar cell according to any one of claims 1 to 12, characterized in that: The solar cell comprises a photovoltaic area and a colorless transparent area. The photovoltaic area is arranged around the colorless transparent area, and the colorless transparent area is a hollow structure.

15. The solar cell according to claim 14, characterized in that: The hollow structure extends from the transparent front electrode to the back electrode; Alternatively, the hollow structure extends from the transparent front electrode to the package back cover.

16. The solar cell according to claim 1, characterized in that The types of solar cells include organic solar cells, perovskite solar cells, dye-sensitized solar cells, and antimony sulfide solar cells.

17. A display device, characterized in that: It comprises a display and the solar cell according to any one of claims 1 to 16, wherein the solar cell is arranged on a surface of the display close to a user, and an image on the display is presented to the user through the solar cell.

Images