Back cover of electronic equipment and electronic equipment

Abstract

The present application provides a back cover of an electronic device and an electronic device, wherein the back cover of the electronic device comprises a glass cover plate, the glass cover plate is used to carry a photoelectric conversion layer; a photoelectric conversion layer, the photoelectric conversion layer is located on the inner surface of the glass cover plate, the photoelectric conversion layer is bonded or bonded to the glass cover plate; a protective layer, the protective layer is located on the surface of the photoelectric conversion layer away from the glass cover plate; and an extraction electrode, the extraction electrode is electrically connected to the photoelectric conversion layer, and is used to output the electricity generated by the photoelectric conversion layer. The technical solution provided by the present application can maintain the wear resistance of the back cover of the electronic device and improve the endurance of the electronic device.

Description

Technical Field

[0001] The present application relates to the technical field of electronic equipment, and in particular, to a back cover of an electronic equipment and the electronic equipment. Background Art

[0002] Smartphones have become an indispensable part of people's daily lives. With the development of technology, mobile phones are updated and replaced at a very fast speed. The discharge capacity of lithium batteries that power different smartphones is different. When users choose a mobile phone, battery life is one of the important indicators of the phone.

[0003] However, the battery life of lithium batteries in current electronic devices is difficult to improve due to the influence of raw materials. Therefore, how to improve the battery life of electronic devices is still one of the technical problems that need to be solved urgently. Summary of the invention

[0004] In view of this, the present application proposes a back cover of an electronic device and an electronic device, which can maintain the wear resistance of the back cover of the electronic device and improve the battery life of the electronic device.

[0005] In a first aspect, the present application provides a back cover of an electronic device, the back cover of the electronic device comprising:

[0006] A glass cover plate, wherein the glass cover plate is used to carry a photoelectric conversion layer;

[0007] A photoelectric conversion layer, the photoelectric conversion layer is located on the inner surface of the glass cover plate, and the photoelectric conversion layer is bonded or connected to the glass cover plate;

[0008] a protective layer, the protective layer being located on a surface of the photoelectric conversion layer away from the glass cover plate; and

[0009] The lead-out electrode is electrically connected to the photoelectric conversion layer and is used to output the electricity generated by the photoelectric conversion layer.

[0010] In the above scheme, a photoelectric conversion layer is prepared on the glass cover plate of the back cover, and light energy is converted into electrical energy through the photoelectric conversion layer, and the electrical energy is output. The electrical energy can be used as a power supply for the power supply device in the electronic device, and can also be stored in the battery module in the electronic device. In addition, the photoelectric conversion layer in the present application is bonded or bonded to the glass cover plate, so that the back cover can protect the electronic device while improving the endurance of the electronic device on the basis of controlling the thickness of the back cover.

[0011] In some embodiments, the photoelectric conversion layer is selected from at least one of silicon-based thin-film solar cells, gallium arsenide thin-film solar cells, copper indium selenide thin-film solar cells, copper indium gallium selenide thin-film solar cells, cadmium telluride thin-film solar cells, perovskite thin-film solar cells, and organic thin-film solar cells.

[0012] In some embodiments, the back cover of the electronic device further includes a heat insulation layer, and the heat insulation layer is located on a surface of the protective layer away from the glass cover plate.

[0013] In some embodiments, the material of the thermal insulation layer includes cesium oxide-stabilized tungsten oxide material and organic resin.

[0014] In some embodiments, the thickness of the thermal insulation layer is 5 μm to 10 μm.

[0015] In some embodiments, the back cover of the electronic device further includes:

[0016] An optical adhesive layer, wherein the optical adhesive layer is located between the glass cover plate and the photoelectric conversion layer, and the glass cover plate and the photoelectric conversion layer are bonded and connected via the optical adhesive layer.

[0017] In some embodiments, the optical adhesive layer has a thickness of 15 μm to 35 μm.

[0018] In some embodiments, the light transmittance of the optical adhesive layer is ≥95%.

[0019] In some embodiments, the photoelectric conversion layer includes an anti-reflection layer, and the glass cover plate and the anti-reflection layer are connected as a whole through metal bonding.

[0020] In some embodiments, the anti-reflection layer includes at least one of silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, titanium oxide, and hafnium oxide.

[0021] In some embodiments, the photoelectric conversion layer is a gallium arsenide thin film solar cell.

[0022] In some embodiments, the glass cover plate has a thickness of 400 μm to 600 μm;

[0023] In some embodiments, the thickness of the photoelectric conversion layer is 1 μm to 100 μm;

[0024] In some embodiments, the thickness of the protective layer is 10 μm to 30 μm;

[0025] In some embodiments, the material of the protective layer is selected from ink.

[0026] In some embodiments, the projected area of ​​the photoelectric conversion layer on the back cover accounts for ≥50%.

[0027] The present application also provides an electronic device, which includes the back cover of the above-mentioned electronic device.

[0028] In some embodiments, the electronic device further includes a middle frame, a display screen, a main board and a battery; the input end of the lead-out electrode is connected to the photoelectric conversion layer, and the output end of the lead-out electrode is connected to the battery, the main board and the display screen.

[0029] In some embodiments, when the power generation of the photoelectric conversion layer of the back cover is less than or equal to the power consumption of the electronic device, the battery and the photoelectric conversion layer jointly supply power to the electronic device;

[0030] When the power generation of the photoelectric conversion layer of the rear cover is greater than the power consumption of the electronic device, the power generation of the photoelectric conversion layer is used to power the electronic device, and the excess power is transmitted to the battery for storage.

[0031] In some embodiments, when the photoelectric conversion layer in the back cover of the electronic device performs photoelectric conversion, the display screen of the electronic device is connected to a heat dissipation device.

[0032] Compared with the prior art, the technical solution of the present application has at least the following beneficial effects: BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a structural schematic diagram of an electronic device provided in an embodiment of the present application;

[0034] Figure 2 A schematic diagram of the structure of a back cover of an electronic device provided in an embodiment of the present application;

[0035] Figure 3 A schematic cross-sectional structure diagram of a back cover of an electronic device provided in an embodiment of the present application;

[0036] Figure 4 A schematic diagram of the structure of a gallium arsenide thin-film solar cell provided in an embodiment of the present application;

[0037] Figure 5 Another structural schematic diagram of a gallium arsenide thin-film solar cell provided in an embodiment of the present application;

[0038] Figure 6 Another structural schematic diagram of a gallium arsenide thin-film solar cell provided in an embodiment of the present application;

[0039] Figure 7 A schematic cross-sectional structure diagram of a back cover of an electronic device provided in an embodiment of the present application;

[0040] Figure 8 A schematic diagram of another cross-sectional structure of a back cover of an electronic device provided in an embodiment of the present application;

[0041] Fig. 9A schematic diagram of another cross-sectional structure of a back cover of an electronic device provided in an embodiment of the present application;

[0042] Fig.10 A schematic diagram of a method for preparing a back cover provided in an embodiment of the present application;

[0043] Fig.11 Another schematic diagram of a method for preparing a back cover provided in an embodiment of the present application;

[0044] Fig.12 A schematic diagram of the connection between the photoelectric conversion layer in the back cover and the mainboard of the electronic device provided in an embodiment of the present application;

[0045] Fig.13 A schematic diagram of the connection between the photoelectric conversion layer in the back cover and the mobile phone motherboard provided in an embodiment of the present application;

[0046] Fig.14 A schematic diagram of a portion of a circuit in an electronic device provided in an embodiment of the present application;

[0047] Fig.15 A schematic diagram of the heat dissipation structure of an electronic device provided in an embodiment of the present application;

[0048] Fig.16a A three-dimensional schematic diagram of a heat dissipation structure of an electronic device provided in an embodiment of the present application;

[0049] Fig.16b A schematic side view of a heat dissipation structure of an electronic device provided in an embodiment of the present application;

[0050] Fig.17a and Fig.17b They are respectively solar charging thermal simulation diagrams of the back cover under different conditions provided in the embodiments of the present application. DETAILED DESCRIPTION

[0051] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0052] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0053] In this application, "first", "second", etc. are used only for descriptive purposes and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features.

[0054] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installation" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0055] In addition, in the present application, directional terms such as "center", "upper", "lower", "inside", "outside", "front", and "back" are defined relative to the orientation or position of the components schematically placed in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, rather than indicating or implying that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. They may change accordingly according to changes in the orientation of the components placed in the drawings, and therefore cannot be understood as limitations of the present application.

[0056] It should also be noted that the same or similar parts in the embodiments of the present application are represented by the same figure mark. For multiple identical parts, the figure may only mark one of the parts or components as an example. It should be understood that the figure mark also applies to other identical parts.

[0057] Smartphones have become an indispensable part of people's daily lives. With the development of technology, mobile phones are updated and replaced at a very fast speed. The discharge capacity of lithium batteries that power different smartphones is different. When users choose a mobile phone, battery life is one of the important indicators of the phone.

[0058] However, the battery life of lithium batteries in current electronic devices is difficult to improve due to the influence of raw materials. Therefore, how to improve the battery life of electronic devices is still one of the technical problems that need to be solved urgently.

[0059] Figure 1 is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application, such as Figure 1 As shown, the electronic device 1000 provided in the embodiment of the present application can be provided with a display screen 200, a housing 400, an internal structure 300, and a back cover 100 in order from top to bottom along the z-axis.

[0060] The display screen 200 can be used to realize the display function of the electronic device. The housing 400 can be used as the main frame of the electronic device to provide rigid support for the electronic device. The internal structure 300 may include a collection of electronic components and mechanical components that realize various functions of the electronic device. Specifically, the internal structure 300 includes a main board, a battery, etc. The back cover 100 may be the back appearance surface of the electronic device.

[0061] The electronic device provided in the embodiments of the present application may be a portable electronic device including other functions such as a personal digital assistant and / or a music player function, such as a mobile phone, a tablet computer, a foldable mobile phone, etc. In some embodiments, the electronic device may further include a processor, an external memory interface, an internal memory, a charging management module, a power management module, a battery, an antenna, a mobile communication module, a wireless communication module, an audio module, a speaker, a microphone, a sensor module, a button, a camera, a display screen, and a subscriber identification module (SIM) card interface, etc. Of course, other required hardware or software may also be included.

[0062] Figure 2 A schematic diagram of the structure of the back cover of the electronic device provided in the embodiment of the present application, as shown in FIG. Figure 2 As shown, the inner surface of the back cover 100 is provided with a photoelectric conversion layer 2. Specifically, the photoelectric conversion layer 2 may be a thin-film solar cell.

[0063] Figure 3 A schematic cross-sectional structure diagram of a back cover of an electronic device provided in an embodiment of the present application is shown in FIG. Figure 3 As shown, the back cover 100 of the electronic device includes a glass cover plate 1, a photoelectric conversion layer 2, a protective layer 5 and an extraction electrode 6. The glass cover plate 1 is used to carry the photoelectric conversion layer 2; the photoelectric conversion layer 2 is located on the inner surface of the glass cover plate 1, and the photoelectric conversion layer 2 is bonded or bonded to the glass cover plate 1; the protective layer 5 is located on the surface of the photoelectric conversion layer 2 away from the glass cover plate 1; the extraction electrode 6 is electrically connected to the photoelectric conversion layer 2, and is used to output the electricity generated by the photoelectric conversion layer.

[0064] In the technical solution provided in the present application, a photoelectric conversion layer is prepared on the glass cover plate of the back cover, and light energy is converted into electrical energy through the photoelectric conversion layer, and the electrical energy is output. The electrical energy can be used as a power supply for the power supply device in the electronic device, and can also be stored in the battery module in the electronic device. In addition, the photoelectric conversion layer in the present application is bonded or bonded to the glass cover plate, so that the back cover can protect the electronic device while improving the endurance of the electronic device on the basis of controlling the thickness of the back cover.

[0065] In order to make the color of the back cover consistent with that of the thin-film solar cell, a protective layer 5 is provided on the surface of the photoelectric conversion layer in the back cover away from the glass cover. The material of the protective layer 5 is selected from ink. The color and material of the ink are not limited and can be adjusted as needed.

[0066] Next, the technical solution of this application is explained in detail by taking a mobile phone as an example of an electronic device:

[0067] The glass cover plate 1 is a light-transmitting glass cover plate. In some embodiments, the glass cover plate can be used as a substrate, and a photoelectric conversion layer 2 is directly formed on the inner surface of the glass cover plate. At this time, the photoelectric conversion layer 2 is bonded to the glass cover plate 1 .

[0068] In other embodiments, the glass cover plate 1 can be used as a substrate, and the photoelectric conversion layer 2 is bonded to the glass cover plate, and can be specifically bonded to the glass cover plate by optical adhesive. It can be understood that the use of optical adhesive bonding can quickly realize the assembly of the glass cover plate and the photoelectric conversion layer, especially some photoelectric conversion layers with smaller thickness can be directly bonded, which will not significantly increase the thickness of the back cover, and can also ensure the photoelectric conversion efficiency and structural stability of the photoelectric conversion layer.

[0069] The width, length and specific material of the glass cover plate 1 are not particularly limited, and those skilled in the art can select them according to actual needs. For example, the width and length can be adapted to the size of the back cover of the mobile phone. The glass cover plate 1 is a good surface protection material for solar cells. The light transmittance of the glass cover plate is ≥95%, and it has a certain level of wear resistance. Specifically, the Mohs hardness of the glass cover plate is ≥5.5.

[0070] In order to efficiently utilize solar energy and improve the endurance of electronic devices, the projection area of ​​the photoelectric conversion layer 2 on the back cover accounts for ≥50%, which can be 50%, 60%, 70%, 80%, 85%, 90% or 95%, etc., which is not limited here. Specifically, the photoelectric conversion layer can be set in other areas of the back cover except the position occupied by the camera module.

[0071] In order to ensure sufficient bearing capacity, the absorption of light by the glass cover plate 1 is reduced so that more light can enter the interior of the photoelectric conversion layer and increase the absorption utilization rate of light by the photoelectric conversion layer 2. Specifically, the thickness of the glass cover plate 1 is 400μm~600μm. For example, the specific value of the thickness can be 400μm, 420μm, 440μm, 450μm, 480μm, 500μm, 520μm, 550μm, 580μm or 600μm, etc., which is not limited here. By controlling the thickness of the glass cover plate 1, the thickness of the entire back cover can be avoided, which is conducive to the lightweighting of electronic equipment.

[0072] In some embodiments, the photoelectric conversion layer 2 is selected from at least one of silicon-based thin-film solar cells, gallium arsenide thin-film solar cells, copper indium selenide thin-film solar cells, copper indium gallium selenide thin-film solar cells, cadmium telluride thin-film solar cells, perovskite thin-film solar cells, and organic thin-film solar cells.

[0073] In order to control the overall thickness of the back cover 100 , the thickness of the photoelectric conversion layer 2 is 10 μm to 200 μm, and can be 30 μm, 40 μm, 50 μm, 60 μm, 80 μm, 100 μm, 130 μm, 150 μm, 180 μm or 200 μm, etc., which is not limited here.

[0074] In some embodiments, the photoelectric conversion layer is a gallium arsenide thin film solar cell. Gallium arsenide is a direct bandgap semiconductor material with a very high absorption coefficient, and the absorption thickness of the battery area in the photoelectric conversion layer is only a few microns. The gallium arsenide solar cell can be designed as a PN junction or an NP junction, in which the highly doped layer is called the emitter and the low-doped layer is called the base. A highly doped ohmic contact layer is grown on the upper and lower surfaces of the solar cell to facilitate ohmic contact with the metal. In order to reduce interface reflection, the solar cell can be covered with an anti-reflection film. The gallium arsenide thin film solar cell can be a single-junction solar cell or a multi-junction solar cell, which is not limited in the present application.

[0075] Figure 4 A schematic diagram of the structure of a gallium arsenide thin film solar cell provided in an embodiment of the present application is shown in FIG. Figure 4 As shown, the gallium arsenide thin film solar cell is a single junction solar cell having a PN junction stacked structure, wherein the layers from top to bottom are a front electrode 21, an anti-reflection film 22, a P-type window layer 23, a P-type emitter layer 24, an N-type base 25, an N-type buffer layer 26, an N-type gallium arsenide substrate 27, and a back electrode 28.

[0076] In some embodiments, the P-type window layer is an aluminum gallium arsenide (AlGaAs) layer, the P-type emitter layer is a gallium arsenide (GaAs) layer, and the N-type base is a gallium arsenide (GaAs) layer.

[0077] Figure 5 Another structural schematic diagram of a gallium arsenide thin film solar cell provided in an embodiment of the present application is shown in FIG. Figure 5 As shown, the gallium arsenide thin film solar cell is preferably a single-junction solar cell, which has an NP junction stacked structure, and the layers from top to bottom are a front electrode 21, an anti-reflection film 22, an N-type window layer 23', an N-type emitter layer 24', a P-type base 25', a P-type buffer layer 26', a P-type gallium arsenide substrate 27', and a back electrode 28.

[0078] In some embodiments, the N-type window layer is an indium gallium phosphide (InGaP) layer, the N-type emitter layer is a gallium arsenide (GaAs) layer, and the P-type base is a gallium arsenide (GaAs) layer.

[0079] like Figure 5 As shown, after preparing a single-junction gallium arsenide thin-film solar cell, the gallium arsenide substrate 27 can be peeled off, and then the bonding technology is used to connect the peeled gallium arsenide thin-film solar cell to the anti-reflection layer on the glass cover 1 through metal bonding. The back electrode can be connected to the cell metallization by the electrode grid line after the gallium arsenide substrate 27 is peeled off, so as to realize the transfer of the cell epitaxial layer to the glass cover 1, and the peeled gallium arsenide substrate bottom can be reused, which effectively reduces the production cost of gallium arsenide solar cells.

[0080] Figure 6 Another structural schematic diagram of a gallium arsenide thin film solar cell provided in an embodiment of the present application is shown in FIG. Figure 6 As shown, the gallium arsenide thin film solar cell is a multi-junction solar cell. In order to absorb the incident light to the maximum extent, when the gallium arsenide thin film solar cell is a multi-junction solar cell, the wavelength range of the absorbed light of each junction cell is different, so that the incident light can be absorbed to the maximum extent. As an example, in this case, the band gap corresponding to each junction cell gradually increases along the direction away from the substrate. Multi-junction solar cells use the different band gaps of Ge, GaAs, GaInP, etc. to absorb solar energy of different frequencies separately, effectively improving the photoelectric conversion efficiency of solar cells.

[0081] In some embodiments, a forward or reverse growth triple junction cell stacking structure can be used on an N-type gallium arsenide substrate. Forward growth means first preparing a bottom cell with a narrow band gap, and then gradually preparing a top cell with a larger band gap; reverse growth is the opposite order of forward growth. Under the same lighting conditions, the triple junction cell has a higher photoelectric conversion efficiency than the gallium arsenide single junction cell structure.

[0082] In some embodiments, the GaAs triple junction solar cell consists mainly of three layers, such as Figure 6 As shown, the gallium arsenide triple-junction solar cell is stacked from top to bottom, including a front electrode 21, a top cell 2a, a first tunneling layer 2b, a GaAs subcell 2c, a second tunneling layer 2d, a gradient transparent layer 2e, a bottom cell 2f, a back electrode 28 and a gallium arsenide substrate 27.

[0083] In some embodiments, the front electrode and the back electrode may be one or a composite electrode of gold, palladium, silver, titanium, chromium, nickel, indium tin oxide (ITO), fluorine-doped tin oxide (FTO), aluminum-doped zinc oxide (AZO). The first tunneling layer and the second tunneling layer are both selected from at least one of heavily doped AlGaAs, GaInP, GaAs, and InGaAs. Preferably, the first tunneling layer and the second tunneling layer are both selected from heavily doped Al 0.3 Ga 0.7 As: C. The material of the gradient transparent layer is Ga x In 1-x P:Si.

[0084] The top cell has the following layers from top to bottom: N-type window layer (Al 0.5 In 0.5 P), N-type emitter layer (InGaP), P-type base (Ga 0.5 In 0.5 P: Zn base, 0.9μm), P-type buffer layer (Al 0.25 Ga 0.25 In 0.5 P). Ga 0.5 In 0.5 The bandgap width of P can reach up to 1.8eV. The GaAs subcell has the following from top to bottom: N-type emitter layer (GaAs), P-type base (GaAs: Zn base, 2.5μm). The top of the GaAs subcell is connected to the top cell through the first tunneling layer, and the bottom is connected to the bottom cell through the second tunneling layer. The bandgap width of GaAs can reach up to 1.4eV. The bottom cell has the following from top to bottom: the first passivation layer, N-type emitter layer (InGaP), P-type base (In 0.3 Ga 0.7 As: Zn base, 2.9 μm), second passivation layer. In 0.3 Ga 0.7 The band gap width of As can reach up to 1.0eV. The first passivation layer and the second passivation layer are both Ga 0.3 In 0.7 P layer.

[0085] It should be noted that although the conversion efficiency of gallium arsenide triple-junction solar cells is high, the material density of the GaAs growth substrate is large and the weight is heavy, which easily limits the application of gallium arsenide triple-junction solar cells in the mobile phone field.

[0086] like Figure 6As shown, after the gallium arsenide triple junction solar cell is prepared, the gallium arsenide substrate 27 can be etched or removed, and then the cell epitaxial layer can be transferred to the glass cover plate 1 by bonding technology. The back electrode can be connected to the cell metallization by the electrode grid line after the gallium arsenide substrate 27 is stripped off, and the stripped substrate can be reused, effectively reducing the production cost of the gallium arsenide solar cell. The substrate can be a silicon-based substrate, a glass substrate, or a GaAs substrate, etc., which is not limited here.

[0087] Figure 7 A schematic cross-sectional structure diagram of a back cover of an electronic device provided in an embodiment of the present application is shown in FIG. Figure 7 As shown, the photoelectric conversion layer 2 in the back cover is a silicon-based thin-film solar cell.

[0088] In some embodiments, the silicon-based thin-film solar cell is a solar cell with a PERC structure, which includes a semiconductor substrate 201, a doping layer 203 and an anti-reflection layer 202 located on the front side of the semiconductor substrate 201; a front electrode 21 located on the surface of the anti-reflection layer 202, the front electrode 21 penetrates the anti-reflection layer 202 and the heavily doped region 203b of the doping layer 203 to form an ohmic contact, and the doping concentration of the heavily doped region 203b is greater than the doping concentration of the lightly doped region 203a; a passivation layer 204 located on the back side of the semiconductor substrate, and a back electrode 28 located on the lower surface of the passivation layer 204, wherein the passivation layer 204 is provided with an opening, and at least a portion of the back electrode 28 passes through the opening to form an electrical contact with the semiconductor substrate 201.

[0089] The above is only an example of a silicon-based thin film solar cell, in which the silicon-based thin film solar cell is directly bonded to the glass cover. In other embodiments, the silicon-based thin film solar cell may also be a silicon-based solar cell with a TopCon structure, which is not limited here.

[0090] In some embodiments, the photoelectric conversion layer is a perovskite thin-film solar cell. When the perovskite thin-film solar cell is exposed to sunlight, the perovskite layer first absorbs photons to generate electron-hole pairs. Due to the difference in exciton binding energy of the perovskite material, these carriers either become free carriers or form excitons; uncombined electrons and holes are collected by the electron transport layer and the hole transport layer, respectively, that is, electrons are transferred from the perovskite layer to the electron transport layer and finally collected by the conductive film; holes are transferred from the perovskite layer to the hole transport layer and finally collected by the metal electrode; a photocurrent is generated by connecting the conductive film and the metal electrode through a circuit.

[0091] In the specific preparation process, a conductive thin film layer (abbreviated as FTO) can be first formed on the inner surface of the glass cover plate, and then a hole transport layer, a perovskite layer, and an electron transport layer are formed in sequence, and finally a protective layer and a lead-out electrode are formed on the surface of the electron transport layer.

[0092] The material of the hole transport layer includes organic materials or inorganic materials. The organic materials include at least one of 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD), poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), and poly3-hexylthiophene (P3HT). The inorganic materials include CuI, CuSCN, NiO, TiO 2 SnO 2 At least one of the above.

[0093] The materials of the perovskite layer include lead iodide methylamine, (Cs) x (FA)1- x PbI 3 、(FA) x (MA) 1-x PbI 3 、(FA) x (MA) 1-x PbI y Cl 1-y ,(FAPbI 3 ) x (MAPbBr 3 ) 1-x At least one of the following, wherein 0<x<1, 0<y<1. The perovskite layer is connected to the hole transport layer, the perovskite layer can absorb sunlight and generate electron-hole pairs, and the hole transport layer can transport the electron-hole pairs from the perovskite layer to the conductive film layer.

[0094] The materials of the electron transport layer include ZnO, TiO 2 SnO 2 、NiO、MoO 3 , fullerene derivatives (PCBM), and at least one of C60.

[0095] It should be noted that the specific formation method and thickness of the conductive film layer, perovskite layer, hole transport layer and electron transport layer are not particularly limited and can be formed by chemical vapor deposition, magnetron sputtering, printing, slit coating, and spraying, which are not limited here.

[0096] As an optional technical solution of the present application, the organic thin-film solar cell can specifically be an organic polymer solar cell. Similarly, when the organic thin-film solar cell is transferred to the glass cover, the substrate of the organic thin-film solar cell can be removed and the glass cover and the anti-reflection layer can be connected as one through metal bonding.

[0097] Figure 8Another cross-sectional structural diagram of a back cover of an electronic device provided in an embodiment of the present application is shown in FIG. Figure 8 As shown, the photoelectric conversion layer includes an anti-reflection layer 3, and the glass cover plate 1 and the anti-reflection layer 3 are connected as a whole by bonding.

[0098] In some embodiments, optical adhesive is used to bond the thin-film solar cell and the glass cover plate, and the optical adhesive layer 4 is located between the glass cover plate 1 and the photoelectric conversion layer 2, and the glass cover plate and the photoelectric conversion layer are bonded and connected through the optical adhesive layer. The transmittance of the optical adhesive layer (POE) is ≥ 95%. It can be understood that the thin-film solar cell and the glass cover plate can be bonded together by a lamination process. Taking the thin-film gallium arsenide solar cell (dark blue) as an example, the ink used to form the protective layer 5 can also be adjusted to dark blue.

[0099] Fig. 9 A schematic diagram of another cross-sectional structure of a back cover of an electronic device provided in an embodiment of the present application is shown in FIG. Fig. 9 As shown, in order to prevent the electronic device from overheating due to the solar energy absorbed by the back cover, the back cover of the electronic device further includes a heat insulating layer 7 , which is located on the surface of the protective layer 5 away from the glass cover plate 1 .

[0100] Generally speaking, the visible light region of sunlight accounts for about 48% of the total solar radiation, ultraviolet light accounts for about 8% of the solar radiation, and infrared light accounts for about 44% of the solar radiation.

[0101] In some embodiments, the material of the thermal insulation layer 7 includes cesium oxide-stabilized tungsten oxide material and organic resin. The thickness of the thermal insulation layer 7 is 5μm~10μm, specifically 5μm, 6μm, 7μm, 8μm, 8.5μm, 9μm or 10μm, etc., which is not limited here. It can be understood that the cesium oxide-stabilized tungsten oxide material and the resin are used to form a thermal insulation layer, which has the effect of heat insulation and sun protection. Among them, the thermal insulation layer 7 has a visible light blocking rate of >50%, a UV light blocking rate of >99%, and an infrared light blocking rate of >95%.

[0102] Fig.10 A schematic diagram of a method for preparing a back cover provided in an embodiment of the present application, such as Fig.10 As shown, in the first step, a transparent optical adhesive layer is coated on the inner surface of the glass cover plate; in the second step, the light-receiving surface of the thin-film solar cell is bonded to the glass cover plate through the optical adhesive layer. In the third step, a protective ink layer is coated on the backlight surface of the thin-film solar cell, and dried to obtain a back cover.

[0103] like Fig.10As shown, the thickness of the optical adhesive layer is 15 μm to 35 μm; specifically, it can be 15 μm, 16 μm, 18 μm, 20 μm, 25 μm, 28 μm, 30 μm, 32 μm or 35 μm, etc., which is not limited here.

[0104] Fig.11 Another schematic diagram of the method for preparing the back cover provided in an embodiment of the present application, in this embodiment, after removing the substrate, the thin-film solar cell is transplanted onto the glass cover plate, wherein the thin-film solar cell is connected to the anti-reflection layer on the glass cover plate by metal bonding. Fig.11 As shown, in the first step, an anti-reflection layer is formed on the inner surface of the glass cover plate (the anti-reflection layer is TiO 2 or Al 2 O 3 ); Step 2: peel off the substrate of the thin-film solar cell, and then connect the peeled surface to the anti-reflection layer through metal bonding. Step 3: coat a layer of ink protective layer on the backlight surface of the thin-film solar cell, and dry it to obtain a back cover.

[0105] Furthermore, in order to realize the output of electric energy of the photoelectric conversion layer on the back cover, the back cover of the electronic device also includes a lead-out electrode 6, the input end of the lead-out electrode 6 is electrically connected to the photoelectric conversion layer, and is used to output the electricity generated by the photoelectric conversion layer; the output end of the lead-out electrode is connected to the battery and other loads in the electronic device. Specifically, the output end of the lead-out electrode can be connected to the main board and the display screen, so that the generated electric energy can be supplied to the main board and the display screen, thereby reducing the loss of power in the battery and improving the battery life of the electronic device.

[0106] Fig.12 A schematic diagram of the connection between the photoelectric conversion layer in the back cover and the mainboard of the electronic device provided in an embodiment of the present application, Fig.13 The schematic diagram of the connection between the photoelectric conversion layer in the back cover and the mobile phone motherboard provided in the embodiment of the present application is as follows: Fig.12 and Fig.13 As shown, the lead electrode 6 is welded to the wire, and the wire is welded to the motherboard of the electronic device through surface mounting technology (SMT). Exemplarily, the wire is made of conductive metal, such as silver wire, copper wire, silver-clad copper wire, etc., which is not limited here.

[0107] At present, the battery of electronic devices (such as mobile phones) is a dual battery, and the dual battery is usually connected in parallel to a charger, such as a buck charger output terminal, wherein the buck charger is used for charge and discharge path management.

[0108] In some embodiments, the electronic device provided by the present application further includes a solar charging management module for managing the output current of the photoelectric conversion layer. Specifically, the solar charging management module is arranged on the main board of the electronic device, and is used in conjunction with a step-down charger. That is, the back cover converts light energy into electrical energy, which is transmitted to the main board of the mobile phone through the lead-out electrode by the wire, and then boosted to an appropriate charging voltage by the solar charging management module, and finally charged to the lithium battery through the internal circuit by the step-down charger.

[0109] Fig.14 A schematic diagram of a partial circuit in an electronic device provided in an embodiment of the present application, such as Fig.14 As shown, when the power generation of the photoelectric conversion layer of the back cover is greater than the power consumption (load) of the electrical devices in the electronic device, the power generation of the photoelectric conversion layer is used to power the electronic device, and the excess power is transmitted to the battery for storage; when the power generation of the photoelectric conversion layer of the back cover is less than or equal to the power consumption (load) of the electrical devices in the electronic device, the battery and the photoelectric conversion layer jointly power the electronic device, thereby fully utilizing the electric energy generated by the back cover.

[0110] In some embodiments, when the photoelectric conversion layer in the back cover is used to charge a battery in an electronic device, when the voltage of the battery is lower than 3.5V, the electronic device automatically shuts down.

[0111] In order to avoid overheating of electronic equipment and improve the service life and charge and discharge cycle performance of the battery, when the battery temperature is detected to be >45° or <0°, the power supply voltage controller controls the solar charging management module to stop charging the battery; when the battery temperature is detected to be between 0° and 45°, the power supply voltage controller controls the solar charging management module to charge the battery with a preset constant current until the battery reaches the constant voltage charging stage, and adjusts the current to continue charging the battery until it is fully charged.

[0112] It should be noted here that lithium battery charging is generally divided into two stages: constant current charging and constant voltage charging. In the constant current charging stage, the charging current is large and the charging rate is fast. After entering the constant voltage charging stage, the current gradually decreases, that is, it enters the trickle charging state, and controls the solar charging management module to continuously charge at a low power until the battery reaches a full state. For example, in the constant current charging stage, the current size can be 782.17mA, and in the constant voltage charging stage, the voltage size can be 4.5V. Of course, it can also be adjusted according to actual needs, and is not limited here.

[0113] The usable area of ​​the photoelectric conversion layer covered later is 8563.5mm 2 For example, the power supply link loss of the photoelectric conversion layer is shown in Table 1:

[0114]

[0115] In order to avoid overheating of electronic devices, when the mobile phone is charged outdoors under sunlight shining on the back cover of the gallium arsenide solar cell, when the detected light intensity reaches the threshold value, the electronic device is controlled to enter power saving mode to reduce its own heating.

[0116] The present application also provides a heat dissipation solution for an electronic device. Fig.15 A schematic diagram of a heat dissipation structure of an electronic device provided in an embodiment of the present application, such as Fig.15 As shown, the internal structure 300 of the electronic device includes a mainboard 301, a battery 302, a heat-conducting layer 303, etc. The material of the heat-conducting layer 303 can be graphene, graphite, etc.; the heat-conducting layer 303 is arranged between the mainboard 301 and the battery 302 and the display screen 200.

[0117] In the present application, when the back cover of the electronic device is charged by solar energy, physical heat dissipation is added on the display screen side of the electronic device. Specifically, the heat generated by the mainboard 301 and the battery 302 caused by sunlight can be conducted to the display screen 200 through the heat conductive layer 303, and then conducted from the display screen 200 to the heat dissipation accessory 600. Exemplarily, the heat dissipation accessory 600 can be in the form of a metal heat sink to increase the heat dissipation area, or a liquid cooling plate, etc., but is not limited to this form.

[0118] Fig.16a A three-dimensional schematic diagram of a heat dissipation structure of an electronic device provided in an embodiment of the present application, Fig.16b A schematic side view of a heat dissipation structure of an electronic device provided in an embodiment of the present application, such as Fig.16a and Fig.16b As shown, the heat dissipation accessory 600 is a fin heat sink, which includes a plurality of fins arranged at intervals, thereby increasing the heat dissipation area. The material of the fin heat sink can be aluminum, aluminum alloy, etc. The height of the fin can be 20 mm, the thickness can be 3 mm, and the fin spacing can be 5 mm. Of course, the size and arrangement density of the fins can also be increased according to the actual required heat dissipation efficiency, which is not limited here.

[0119] Fig.17a and Fig.17b They are respectively solar charging heat simulation diagrams of the back cover under different conditions provided by the embodiments of the present application, such as Fig.17a As shown in the figure, through the thermal simulation analysis of solar charging of mobile phones, when the solar energy is 1000W / m² and the ambient temperature is 25℃, the thermal simulation result shows that the maximum temperature of the lithium battery in the mobile phone is 47.82℃; Fig.17b As shown in the figure, after adding the heat dissipation accessories, the thermal simulation results show that the maximum temperature of the lithium battery in the mobile phone is 42.23℃, and the temperature drops significantly, which shows that the configured heat dissipation accessories can effectively reduce the temperature inside the mobile phone.

[0120] In some embodiments, a heat insulating layer 7 is provided on the surface of the protective layer of the back cover of the electronic device. During the solar charging process, the synergistic heat dissipation effect of the heat dissipation accessories and the heat insulating layer 7 can be utilized. After testing, it was found that when the direct solar energy is 1000W / m², the ambient temperature is 25°C, and the heat dissipation accessories and the heat insulating layer are added, the thermal simulation result shows that the maximum temperature of the lithium battery in the mobile phone is 41.28°C, and the heat dissipation capacity is further improved.

[0121] The present application applies thin-film solar cells to the back cover of an electronic device, so that the thin-film solar cells can be used to provide power to the electronic device, thereby improving the battery life of the mobile phone without affecting the user's hand-held touch, maintaining the wear resistance of the original mobile phone battery cover, combining the appearance design, and the thickness of the back cover of the electronic device will not be significantly increased.

[0122] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core ideas of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A back cover of an electronic device, characterized in that: The back cover of the electronic device comprises: A glass cover plate, the glass cover plate is used to carry the photoelectric conversion layer, and an anti-reflection layer is formed on the inner surface of the glass cover plate; A photoelectric conversion layer, the photoelectric conversion layer is located on the inner surface of the glass cover plate, the photoelectric conversion layer is a gallium arsenide thin film solar cell after the substrate is peeled off, the peeling surface of the gallium arsenide thin film solar cell after the substrate is peeled off is connected to the anti-reflection layer as a whole through metal bonding, and the thickness of the photoelectric conversion layer is 1 μm to 40 μm; a protective layer, the protective layer being located on a surface of the photoelectric conversion layer away from the glass cover plate; and The lead-out electrode is electrically connected to the photoelectric conversion layer and is used to output the electricity generated by the photoelectric conversion layer.

2. The back cover of the electronic device according to claim 1, characterized in that: The back cover of the electronic device further includes: A heat insulation layer is located on a surface of the protection layer away from the glass cover plate.

3. The back cover of the electronic device according to claim 2, characterized in that: The material of the heat insulation layer includes cesium oxide-stabilized tungsten oxide material and organic resin; and / or; the thickness of the heat insulation layer is 5 μm to 10 μm.

4. The back cover of the electronic device according to claim 1, characterized in that: The anti-reflection layer includes at least one of silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, titanium oxide and hafnium oxide.

5. The back cover of the electronic device according to claim 1, characterized in that: It meets at least one of the following characteristics: 1) The thickness of the glass cover plate is 400 μm to 600 μm; 2) The thickness of the protective layer is 10 μm to 30 μm; 3) The material of the protective layer is selected from ink.

6. The back cover of the electronic device according to claim 1, characterized in that: The projected area of ​​the photoelectric conversion layer on the back cover accounts for ≥50%.

7. An electronic device, characterized in that: The electronic device comprises the back cover of the electronic device according to any one of claims 1 to 6.

8. The electronic device according to claim 7, characterized in that: The electronic device further comprises a middle frame, a display screen, a main board and a battery; the input end of the lead-out electrode is connected to the photoelectric conversion layer, and the output end of the lead-out electrode is connected to the battery, the main board and the display screen.

9. The electronic device according to claim 8, characterized in that: When the power generation of the photoelectric conversion layer of the back cover is less than or equal to the power consumption of the electronic device, the battery and the photoelectric conversion layer jointly supply power to the electronic device; When the power generation of the photoelectric conversion layer of the rear cover is greater than the power consumption of the electronic device, the power generation of the photoelectric conversion layer is used to power the electronic device, and the excess power is transmitted to the battery for storage.

10. The electronic device according to claim 8, characterized in that: When the photoelectric conversion layer in the back cover of the electronic device performs photoelectric conversion, the display screen of the electronic device is connected to the heat dissipation device.

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