Solar cell, manufacturing method thereof and display device

Abstract

The invention discloses a solar cell, a manufacturing method thereof 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 metal protection layer is arranged on the surface of the photovoltaic layer; the back electrode is arranged on the surface of the metal protection layer; and the packaging layer is arranged on one side, far away from the metal protection layer, of the back electrode. Wherein the metal protection layer comprises one or more of Ag, Al, Cr, Cu, Au, Pt, Mo, Ti, Sn and Mg. A metal protection layer is arranged on the surface of a photovoltaic layer and serves as a mask for performing a patterning process on the photovoltaic layer, so that the patterning of the photovoltaic layer is realized. And on the other hand, the metal protection layer is adopted as a mask and does not need to be removed after patterning of the photovoltaic layer, and on the contrary, the electric contact performance between the back electrode and the photovoltaic layer can be improved.

Description

Technical Field

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

[0002] With the rapid development of electronic technology, people have put forward higher and higher requirements on the battery life of various portable electronic products and the power supply emergency plan in the event of an emergency or emergency. At present, the solution to this problem is to configure an additional solar cell for various electronic devices. Usually, when electronic products are equipped with external solar cells, in order to make the solar cells obtain the maximum light absorption intensity, the solar cells are generally set on the upper surface of the display. In this design, it is necessary to refer to the outer dimensions of the display to pattern the solar cells and make them so that the display screen below can be fully presented. Similar to the structure of the display, the solar cell also has a VA (View Area) area and a non-VA area. The non-VA area of ​​the solar cell is provided with a photovoltaic layer, and corresponds to the non-VA area of ​​the display. The VA area of ​​the solar cell basically overlaps with the VA area of ​​the display. In view of the design of the above structure, how to pattern the solar cell is a major problem in the design and manufacture of solar cells.

[0003] Unlike the materials and manufacturing processes used in amorphous silicon solar cells, organic solar cells, perovskite solar cells, nano-quantum dot solar cells, organic-inorganic hybrid solar cells, and other solar cells that need to be encapsulated before use, because the materials used are sensitive to water and oxygen, it is very easy to cause device failure after absorbing water and oxygen. In addition, the photovoltaic materials of these cells have poor tolerance to chemicals commonly used in the electronics industry, resulting in the inability to use the usual yellow light process to produce the required patterns. At present, since polymers or perovskites or quantum dots with high photoelectric conversion efficiency need to be formed into films by solution methods, when making such solar cells, the entire surface is coated and cured, and then divided into sections using a laser scribing process to make a single-section or multi-section solar cell on the entire surface. Due to the limitations of the above methods, it becomes more difficult to produce a solar cell with a transparent display area corresponding to the display. Summary of the invention

[0004] The present application provides a solar cell, a manufacturing method thereof and a display device, which meet the requirements of solar cell patterning by optimizing the device structure of the solar cell.

[0005] The purpose of this application is achieved through the following technical solutions:

[0006] One embodiment of the present application provides a solar cell, comprising:

[0007] Transparent substrate;

[0008] A transparent front electrode is arranged on the surface of the transparent substrate;

[0009] A photovoltaic layer is arranged on the surface of the transparent front electrode;

[0010] A metal protective layer, disposed on the surface of the photovoltaic layer;

[0011] a back electrode, disposed on the surface of the metal protection layer; and

[0012] An encapsulation layer is arranged on a side of the back electrode away from the metal protection layer;

[0013] Wherein, the metal protective layer includes one or more of Ag, Al, Cr, Cu, Au, Mo, Ti, Sn, and Mg.

[0014] In one of the embodiments, the cross-sectional width of the photovoltaic layer in the vertical direction is greater than the cross-sectional width of the transparent front electrode in the vertical direction, so that the photovoltaic layer completely covers the transparent front electrode.

[0015] In one of the embodiments, a difference between a cross-sectional width of the photovoltaic layer in the vertical direction and a cross-sectional width of the transparent front electrode in the vertical direction is greater than or equal to 50 μm.

[0016] In one of the embodiments, a difference between a cross-sectional width of the metal protection layer in the vertical direction and a cross-sectional width of the transparent front electrode in the vertical direction is greater than or equal to 20 μm.

[0017] In one embodiment, the back electrode has an overlapping region and a non-overlapping region:

[0018] In the non-overlapping area, the cross-sectional width of the back electrode in the vertical direction is less than or equal to the cross-sectional width of the metal protection layer in the vertical direction;

[0019] In the overlapping area, the transparent front electrode has an electrode overlapping block, and the back electrode extends outward to the electrode overlapping block of the transparent front electrode and is electrically connected to the electrode overlapping block.

[0020] In one embodiment, the photovoltaic layer and the metal protective layer also cover the electrode bridge block;

[0021] In the area covering the electrode strapping block, the metal protection layer and the photovoltaic layer have through holes, and the back electrode passes through the through holes to be electrically connected to the electrode strapping block.

[0022] In one embodiment, the solar cell further comprises:

[0023] The auxiliary metal layer is arranged on the upper surface or the lower surface of the transparent front electrode. The auxiliary metal layer is used to improve the charge collection and conduction capabilities of the transparent front electrode.

[0024] In one embodiment, the auxiliary metal layer includes a main body and an extension portion:

[0025] The body of the auxiliary metal layer is disposed in an outer edge region of the transparent front electrode;

[0026] The extension portion of the auxiliary metal layer extends inward from the main body to form a multi-segment line shape or a grid shape.

[0027] In one of the embodiments, the line width of the main body and the extension portion of the auxiliary metal layer is less than or equal to 20 μm.

[0028] In one embodiment, the distance between two adjacent lines of the extension portion of the auxiliary metal layer is less than 1 cm.

[0029] In one embodiment, the solar cell further comprises:

[0030] The first insulating layer is arranged at the outer edge and / or inner edge region of the transparent front electrode and between the transparent front electrode and the photovoltaic layer.

[0031] In one embodiment, the solar cell further comprises:

[0032] The second insulating layer is arranged at the outer edge and / or inner edge region of the photovoltaic layer and between the photovoltaic layer and the metal protective layer.

[0033] In one embodiment, the solar cell is an organic solar cell, a perovskite solar cell, a nano-quantum dot solar cell or an organic-inorganic hybrid solar cell.

[0034] In one of the embodiments, the material used to make the back electrode includes one or more of Ag, Al, Cr, Cu, Au, Pt, Mg, Mo, Ti, Sn, conductive polymer, TCO, nanosilver, graphene, and carbon nanotubes.

[0035] In one embodiment, the packaging layer is made of one or more materials including an atomic deposition layer, a TFE film packaging layer, a polymer film composited with a water and oxygen barrier layer, and a metal, glass or quartz substrate coated with an adhesive.

[0036] Another embodiment of the present application further provides a method for manufacturing a solar cell, comprising the following steps:

[0037] providing a transparent substrate;

[0038] Disposing a transparent front electrode on the surface of the transparent substrate;

[0039] Disposing a photovoltaic layer on the surface of the transparent front electrode;

[0040] Disposing a metal protective layer on the surface of the photovoltaic layer;

[0041] Using the metal protective layer as a mask to remove part of the photovoltaic layer to produce a photovoltaic layer pattern;

[0042] Disposing a back electrode on the surface of the metal protective layer;

[0043] A packaging layer is disposed on a side of the back electrode away from the metal protection layer.

[0044] In one of the embodiments, when the transparent front electrode is provided, an auxiliary metal layer may be provided on the upper surface or the lower surface of the transparent front electrode.

[0045] In one of the embodiments, when the photovoltaic layer is provided, a first insulating layer is first provided on the outer edge and / or inner edge region of the transparent front electrode.

[0046] Another embodiment of the present application further provides a display device, including a display and a solar cell as described in any one of the above embodiments.

[0047] Compared with the prior art, the solar cell provided by the present application has the following advantages and beneficial effects:

[0048] In the solar cell provided in the present application, by setting a metal protective layer on the surface of the photovoltaic layer, the metal protective layer can be used as a mask for patterning the photovoltaic layer, thereby selecting effective solvents or gases of different properties or functions to remove the photovoltaic layer outside the metal protective layer, thereby realizing the patterning of the photovoltaic layer. On the other hand, the metal protective layer is used as a mask, and since the metal protective layer has good conductivity, it does not need to be removed after the photovoltaic layer is patterned. Even the metal protective layer set between the back electrode and the photovoltaic layer can increase the electrical contact performance between the back electrode and the photovoltaic layer. In fact, due to the production of the photovoltaic layer of solar cells such as organic solar cells and perovskite solar cells, the film is mostly formed by whole-surface coating, and the chemical properties of the various functional layer solutions constituting the photovoltaic layer are different. Polar materials show hydrophilicity, and non-polar materials show hydrophobicity. Moreover, these photovoltaic materials are sensitive to water vapor and oxygen, and cannot directly contact with water and commonly used developer and stripping liquid. Therefore, it is impossible to produce the required pattern by the usual yellow light process. In view of this, after the photovoltaic layer is formed, a metal protective layer is first made, and the metal protective layer is used as the protective layer of the patterning process. Effective solvents or gases of photovoltaic layers with different properties and functions are selected to dissolve, rinse or chemically react the hole transport layer, photovoltaic active layer and electron transport layer in the photovoltaic layer layer layer by layer to remove the photovoltaic layer except the metal protective layer, and finally realize the patterning of the photovoltaic layer. The solvent for dissolving the photovoltaic layer includes ethanol, chloroform, isopropanol, benzene, toluene, Cl 2 Such solvents can only dissolve and remove photovoltaic materials without damaging the metal protective layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 is a schematic diagram of the structure of a solar cell provided in one of the embodiments of the present application;

[0050] Figure 2 is a schematic structural diagram of a solar cell provided by another embodiment of the present application;

[0051] Figure 3 is a schematic diagram of the structure of a display device provided in one embodiment of the present application;

[0052] Figure 4 yes Figure 1 Schematic diagram of the planar structure of the transparent front electrode;

[0053] Figure 5 yes Figure 1 Schematic diagram of the planar structure of the auxiliary metal layer;

[0054] Figure 6 yes Figure 1 Another schematic diagram of the planar structure of the auxiliary metal layer;

[0055] Figure 7 yes Figure 1 A schematic diagram of another planar structure of the auxiliary metal layer in FIG.

[0056] Figure 8 yes Figure 1 Schematic diagram of the planar structure of the photovoltaic layer;

[0057] Fig. 9 yes Figure 1 Schematic diagram of another planar structure of the photovoltaic layer;

[0058] Fig.10 yes Figure 1 A schematic diagram of another planar structure of the photovoltaic layer in FIG.

[0059] Fig.11 yes Figure 1 Schematic diagram of the planar structure of the metal protective layer;

[0060] Fig.12 yes Figure 1 Another schematic diagram of the planar structure of the metal protective layer;

[0061] Fig.13 yes Figure 1 A schematic diagram of another planar structure of the metal protective layer in FIG.

[0062] Fig.14 yes Figure 1 A schematic diagram of a planar structure in which a transparent substrate, a transparent front electrode, an auxiliary metal layer and a photovoltaic layer are combined together;

[0063] Fig.15 yes Fig.14 An enlarged schematic diagram of the E1 region in FIG.

[0064] Fig.16 yes Figure 1 Schematic diagram of the planar structure of the back electrode in FIG.

[0065] Fig.17 yes Figure 1 Schematic diagram of the planar structure of the solar cell;

[0066] Fig.18 yes Figure 1 Another schematic diagram of a planar structure of a solar cell;

[0067] Fig.19 yes Fig.18 Schematic diagram of the cross section of the solar cell along the BB direction;

[0068] Fig. 20 It is a schematic diagram of the planar structure of the transparent front electrode of a multi-junction solar cell;

[0069] Fig.21 It is a schematic diagram of the planar structure of the auxiliary metal layer of a multi-junction solar cell;

[0070] Fig. 22 It is a schematic diagram of the planar structure of the photovoltaic layer of a multi-junction solar cell;

[0071] Fig.23 It is another schematic diagram of the planar structure of the photovoltaic layer of a multi-junction solar cell;

[0072] Fig.24 It is another schematic diagram of the planar structure of the photovoltaic layer of a multi-junction solar cell;

[0073] Fig.25 It is a schematic diagram of the planar structure of the metal protective layer of a multi-junction solar cell;

[0074] Fig.26 It is another schematic diagram of the planar structure of the metal protective layer of a multi-junction solar cell;

[0075] Fig. 27 It is another schematic diagram of a planar structure of a metal protective layer of a multi-junction solar cell;

[0076] Fig.28 It is a schematic diagram of a planar structure in which a transparent substrate, a transparent front electrode, an auxiliary metal layer and a photovoltaic layer of a multi-junction solar cell are combined together;

[0077] Fig.29 yes Fig.28 A magnified schematic diagram of the E2 region in the middle;

[0078] Fig.30 It is a schematic diagram of the planar structure of the back electrode of a multi-junction solar cell;

[0079] Fig.31 is a schematic diagram of a planar structure of a multi-junction solar cell provided in one embodiment of the present application;

[0080] Fig.32 is a schematic diagram of a planar structure of a multi-junction solar cell provided by another embodiment of the present application;

[0081] Fig.33 yes Fig.31 Schematic diagram of the cross section of the multi-junction solar cell along the CC direction;

[0082] Fig.34 yes Fig.32 Schematic diagram of the cross section of the multi-junction solar cell along the DD direction; DETAILED DESCRIPTION

[0083] The present application will be further described in detail below in conjunction with examples, but the implementation methods of the present application are not limited thereto.

[0084] See also Figure 1 One embodiment of the present application provides a solar cell 100. In this embodiment, the solar cell 100 may be an organic solar cell, a perovskite solar cell, a nano-quantum dot solar cell, or an organic-inorganic hybrid solar cell. The solar cell 100 includes:

[0085] Transparent substrate 110;

[0086] A transparent front electrode 120 is disposed on the surface of the transparent substrate 110;

[0087] The photovoltaic layer 130 is disposed on the surface of the transparent front electrode 120;

[0088] A metal protective layer 140 is disposed on the surface of the photovoltaic layer 130; and

[0089] A back electrode 150 is disposed on the surface of the metal protection layer 140;

[0090] The metal protection layer 140 includes one or more of Ag, Al, Cr, Cu, Au, Pt, Mo, Ti, Sn, and Mg.

[0091] Please also see Figure 3 As required, the solar cell 100 further includes an encapsulation layer 160. The encapsulation layer 160 and the transparent substrate 110 together clamp the transparent front electrode 120, the photovoltaic layer 130, the metal protection layer 140, and the back electrode 150. In this embodiment, the encapsulation layer 160 is made of one or more materials including an atomic layer deposition (ALD), a TFE film encapsulation layer, a polymer film composited with a water and oxygen barrier layer, and a metal, glass, or quartz substrate coated with an adhesive.

[0092] In the solar cell 100 provided in the above embodiment, by providing a metal protective layer 140 on the surface of the photovoltaic layer 130, the metal protective layer 140 can be used as a mask for patterning the photovoltaic layer 130, thereby selecting effective solvents or gases with different properties or functions to remove the photovoltaic layer outside the metal protective layer 140, thereby achieving patterning of the photovoltaic layer 130. On the other hand, the metal protective layer 140 is used as a mask, and since the metal protective layer 140 has good conductivity, it does not need to be removed after the photovoltaic layer 130 is patterned. In fact, the metal protective layer 140 provided between the back electrode 150 and the photovoltaic layer 130 can increase the electrical contact performance between the back electrode 150 and the photovoltaic layer 130. In fact, since the photovoltaic layer of organic solar cells, perovskite solar cells and other types of solar cells is mostly formed by coating the entire surface, the chemical properties of the various functional layer solutions that constitute the photovoltaic layer are different. Polar materials are hydrophilic, and non-polar materials are hydrophobic. In addition, these photovoltaic materials are sensitive to water vapor and oxygen and cannot directly contact water and commonly used developer and stripping liquid. Therefore, it is impossible to produce the required pattern by the usual yellow light process. In view of this, in this embodiment, after the photovoltaic layer 130 is formed, a metal protective layer 140 is first produced, and the metal protective layer 140 is used as the protective layer of the patterning process. Effective solvents or gases for photovoltaic layers with different properties and functions are selected to dissolve, rinse or chemically react the hole transport layer, photovoltaic active layer, and electron transport layer in the photovoltaic layer 130 layer by layer to remove the photovoltaic layer 130 outside the metal protective layer 140, and finally achieve patterning of the photovoltaic layer 130. The solvent for dissolving the photovoltaic layer 130 includes ethanol, chloroform, isopropanol, benzene, toluene, Cl 2 Such solvents can only dissolve and remove photovoltaic materials without damaging the metal protective layer 140 .

[0093] As required, the solar cell 100 further includes an auxiliary metal layer 170. The auxiliary metal layer 170 is disposed on the upper surface or the lower surface of the transparent front electrode 120. The auxiliary metal layer 170 is used to improve the charge collection and conduction capabilities of the transparent front electrode 120. In this embodiment, the auxiliary metal layer 170 is used to reduce the surface resistance of the transparent front electrode 120. As required, the auxiliary metal layer 170 can be disposed at the periphery of the solar cell 100 and in the effective power generation area, respectively. The material of the auxiliary metal layer 170 is composed of one or more of Ag, Al, Cr, Cu, Au, Pt, Mo, Ti, Sn, and Mg metals.

[0094] As required, the transparent front electrode 120 has an electrode bridging block 121. In this embodiment, the electrode bridging block 121 is connected to the negative electrode of the solar cell 100. When the back electrode 150 covers the surface of the metal protective layer 140, the other end of the back electrode 150 is electrically connected to the negative electrode bridging block 121 of the transparent front electrode 120.

[0095] In fact, the solar cell is not limited to the above implementation. Furthermore, in order to improve the fill factor of the solar cell device, an insulating layer is provided between the transparent front electrode and the photovoltaic layer, or between the photovoltaic layer and the BF protective layer. The insulating layer only fills the area between the effective power generation area and the area outside the electrode overlap area, covering the electrode edge, which can avoid the short circuit of the positive and negative electrodes when the photovoltaic layer breaks when it is coated on the electrode edge.

[0096] Please also see Figure 2 Another embodiment of the present application provides a solar cell 200. The solar cell 200 includes:

[0097] Transparent substrate 210;

[0098] A transparent front electrode 220 is disposed on the surface of the transparent substrate 210;

[0099] The photovoltaic layer 230 is disposed on the surface of the transparent front electrode 220;

[0100] A metal protective layer 240 is disposed on the surface of the photovoltaic layer 230; and

[0101] A back electrode 250 is disposed on the surface of the metal protection layer 240;

[0102] The metal protection layer 240 includes one or more of Ag, Al, Cr, Cu, Au, Pt, Mo, Ti, Sn, and Mg.

[0103] Different from the previous embodiment, the solar cell 200 further includes:

[0104] The first insulating layer 280 is disposed at the outer edge and / or inner edge region of the transparent front electrode 220 , and is disposed between the transparent front electrode 220 and the photovoltaic layer 230 .

[0105] Similarly, the solar cell 200 further includes a second insulating layer (not shown). The second insulating layer is disposed at the outer edge and / or inner edge region of the photovoltaic layer 230 and between the photovoltaic layer 230 and the metal protection layer 240 .

[0106] As required, the solar cell 200 further includes an auxiliary metal layer 270. The auxiliary metal layer 270 is disposed on the upper surface or the lower surface of the transparent front electrode 220. In this embodiment, the auxiliary metal layer 270 is used to reduce the surface resistance of the transparent front electrode 220. As required, the auxiliary metal layer 270 can be disposed at the periphery of the solar cell 100 and in the effective power generation area, respectively. The material of the auxiliary metal layer 270 is composed of one or more of Ag, Al, Cr, Cu, Au, Mo, Ti, Sn, and Mg metals.

[0107] As required, the transparent front electrode 220 has an electrode bridging block 221 . When the back electrode 250 covers the surface of the metal protection layer 240 , the other end of the back electrode 250 is electrically connected to the negative electrode bridging block 221 of the transparent front electrode 220 .

[0108] Please also see Figure 3 Another embodiment of the present application further provides a display device 300. The display device 300 includes a display 310 and a solar cell 100 as described in any one of the above embodiments.

[0109] In the present embodiment, the display device 300 further includes a protective cover plate 320. The display 310 and the protective cover plate 320 together clamp the solar cell 100 in the middle. In the present embodiment, the solar cell 100 includes a VA area and a non-VA area. The VA area is used to allow the image displayed in the VA area of ​​the display 300 to pass through. The photovoltaic functional area of ​​the solar cell 100 is arranged in the non-VA area, and is used to receive external light to generate energy, thereby replenishing electrical energy for the display 310. In the present embodiment, the visible light transmittance of the light-transmitting area of ​​the solar cell 100 is between 40% and 90%. The light-transmitting area of ​​the solar cell is made using a graphical process.

[0110] The solar cell is manufactured by the following method:

[0111] providing a transparent substrate;

[0112] Disposing a transparent front electrode on the surface of the transparent substrate;

[0113] Disposing a photovoltaic layer on the surface of the transparent front electrode;

[0114] Disposing a metal protective layer on the surface of the photovoltaic layer;

[0115] Using the metal protective layer as a mask to remove part of the photovoltaic layer to produce a photovoltaic layer pattern;

[0116] Disposing a back electrode on the surface of the metal protective layer;

[0117] A packaging layer is disposed on a side of the back electrode away from the metal protection layer.

[0118] In one of the embodiments, when the transparent front electrode is provided, an auxiliary metal layer may be provided on the upper surface or the lower surface of the transparent front electrode.

[0119] In one of the embodiments, when the photovoltaic layer is provided, a first insulating layer is first provided on the outer edge and / or inner edge region of the transparent front electrode.

[0120] The following is a specific implementation method to illustrate how to manufacture the solar cell provided by the present application.

[0121] For a single-junction solar cell, the solar cell 100 is manufactured by:

[0122] Provide a transparent substrate 110. The transparent substrate 110 includes but is not limited to being made of rigid materials such as glass, quartz, sapphire, 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), etc.

[0123] A transparent front electrode 120 is disposed on the surface of the transparent substrate 110. In this embodiment, the transparent front electrode 120 is made of materials including but not limited to TCO, nanosilver, graphene, and carbon nanotubes. Figure 4 The transparent front electrode 120 is in the shape of a ring. A positive electrode lead-out terminal and a negative electrode lead-out terminal are disposed on one side of the transparent front electrode 120. The transparent front electrode 120 has an electrode bridge block 121 as required.

[0124] An auxiliary metal layer 170 is disposed on the surface of the transparent front electrode 120. The material of the auxiliary metal layer 170 is composed of one or more of Ag, Al, Cr, Cu, Au, Pt, Mo, Ti, Sn, and Mg. Figure 5 , the auxiliary metal layer 170 is arranged at the edge of the transparent front electrode 120, and also has a positive lead-out terminal and a negative lead-out terminal. As needed, the auxiliary metal layer 170 can be firstly made on the transparent substrate 110, and then the transparent front electrode 120 can be made on the transparent substrate 110 to cover the auxiliary metal layer 170. The transparent front electrode 120 can also be firstly made on the transparent substrate 110, and then the auxiliary metal layer 170 is made on the surface of the transparent front electrode 120. In this embodiment, the auxiliary metal layer 170 is in a circular ring shape and is arranged at the outer edge area of ​​the transparent front electrode 120.

[0125] In fact, the auxiliary metal layer 170 is not limited to the above embodiments. Figure 6 In another embodiment, the auxiliary metal layer 170 includes a body 171 and an extension 172. The body 171 of the auxiliary metal layer 170 is disposed at the outer edge region of the transparent front electrode 120. The extension 172 of the auxiliary metal layer 170 extends inward from the body 171 to form a multi-segment line shape.

[0126] In this embodiment, by configuring the auxiliary metal layer 170 to include a main body 171 and an extension portion 172, and allowing the extension portion 172 of the auxiliary metal layer 170 to extend inward from the main body 171 to form a multi-segment line shape, the auxiliary metal layer 170 and the extension portion 172 can improve the charge collection and conduction capabilities of the transparent front electrode 120.

[0127] As required, the auxiliary metal layer is not limited to the above embodiments. Figure 7 In another embodiment, the auxiliary metal layer 170 includes a body 171 and an extension 172. The body 171 of the auxiliary metal layer 170 is disposed in an outer edge region of the transparent front electrode 120. The extension 172 of the auxiliary metal layer 170 extends inward from the body 171 to form a grid shape.

[0128] In this embodiment, by arranging the extension portion 172 into a grid shape, the extension portion 172 can also improve the charge collection and conduction capabilities of the transparent front electrode 120 .

[0129] It can be understood that in the above embodiment, the line width of the main body 171 and the extension 172 of the auxiliary metal layer 170 is less than or equal to 20 μm. The distance between two adjacent lines of the extension 172 of the auxiliary metal layer 170 is less than 1 cm. The above arrangement can effectively improve the charge collection capability of the transparent front electrode 120.

[0130] In fact, when the solar cell 100 is set as a single junction device, the auxiliary metal layer 170 is set as far as possible outside the effective power generation area of ​​the solar cell 100. In addition, in order to improve the charge collection and conduction capabilities, an auxiliary metal in the form of lines or grids can also be set in the corresponding area of ​​the effective power generation area (photovoltaic layer) of the solar cell 100. When the auxiliary metal lines or metal grids are set in the effective power generation area, at least one lead-out line is connected to or adjacent to the auxiliary metal lines outside the effective power generation area. When set to be adjacent, the maximum distance between two adjacent auxiliary metal lines is less than 1 cm. The preferred design of the metal lines or metal grids is to be evenly distributed in the effective power generation area, dividing the transparent front electrode in the effective power generation area into multiple parts of similar area. The line width of the metal lines or metal grids entering the PV photovoltaic area is less than or equal to 20μm.

[0131] A photovoltaic layer 130 is disposed on the surface of the transparent front electrode 120. In this embodiment, the photovoltaic layer 130 is in a ring shape. The photovoltaic layer 130 includes at least one group of electron or hole transport layers, photovoltaic active layers, and hole or electron transport layers that are stacked in sequence. Figure 8 , the photovoltaic layer 130 completely covers the transparent front electrode 120 .

[0132] In fact, the photovoltaic layer 130 is not limited to the above embodiments. Fig. 9 In another embodiment, the photovoltaic layer 130 further includes a protrusion 131. The protrusion 131 of the photovoltaic layer 130 covers the electrode lap block 121 of the transparent front electrode 120. As required, the protrusion 131 of the photovoltaic layer 130 has a plurality of through holes 132. By providing a plurality of through holes 132 on the protrusion 131 of the photovoltaic layer 130, in the subsequent process of manufacturing the back electrode 150, the back electrode 150 can be electrically connected to the negative electrode lap block 121 through the through holes 132 on the protrusion 131 of the photovoltaic layer 130.

[0133] The shape of the through hole is not limited to the above embodiment. Fig.10 In another embodiment, the photovoltaic layer 130 further includes a protrusion 131. The protrusion 131 of the photovoltaic layer 130 covers the electrode lap block 121 of the transparent front electrode 120. As required, the protrusion 131 of the photovoltaic layer 130 has an elongated through hole 133. By providing an elongated through hole 133 on the protrusion 131 of the photovoltaic layer 130, in the subsequent process of manufacturing the back electrode 150, the back electrode 150 can be electrically connected to the negative electrode lap block 121 through the elongated through hole 133 on the protrusion 131 of the photovoltaic layer 130.

[0134] A metal protective layer 140 is disposed on the surface of the photovoltaic layer 130. In fact, the patterning of the photovoltaic layer 130 is performed after the metal protective layer 140 is disposed. Specifically, the metal protective layer 140 is used as a mask to remove part of the photovoltaic layer 130 to produce a photovoltaic layer pattern. Fig.11 In this embodiment, the metal protection layer 140 is in a circular ring shape, so that the photovoltaic layer 130 is also in a circular ring shape after patterning.

[0135] In fact, the metal protection layer 140 is not limited to the above embodiments. Fig.12 In another embodiment, the metal protective layer 140 further includes a protrusion 141. The protrusion 141 of the metal protective layer 140 covers the electrode bridge block 121 of the transparent front electrode 120. As required, the protrusion 141 of the metal protective layer 140 has a plurality of through holes 142. By providing a plurality of through holes 142 on the protrusion 141 of the metal protective layer 140, in the subsequent process of manufacturing the back electrode 150, the back electrode 150 can be electrically connected to the negative electrode bridge block 121 through the through holes 142 on the protrusion 141 of the metal protective layer 140. In fact, since the metal protective layer 140 has a protrusion 141 and a plurality of through holes 142 on the protrusion 141, when the metal protective layer 140 is used as a mask to pattern the photovoltaic layer 130, the photovoltaic layer 130 will also have a protrusion 131 and a plurality of through holes 132 on the protrusion 131.

[0136] The shape of the through hole is not limited to the above embodiment. Fig.13 In another embodiment, the metal protective layer 140 further includes a protrusion 141. The protrusion 141 of the metal protective layer 140 covers the negative electrode bridge block 121 of the transparent front electrode 120. As required, the protrusion 141 of the metal protective layer 140 has a long strip-shaped through hole 143. By providing a long strip-shaped through hole 143 on the protrusion 141 of the metal protective layer 140, in the subsequent process of manufacturing the back electrode 150, the back electrode 150 can be electrically connected to the negative electrode bridge block 121 through the long strip-shaped through hole 143 on the protrusion 141 of the metal protective layer 140. In fact, since the metal protective layer 140 has a protrusion 141 and the protrusion 141 has a long strip-shaped through hole 143, when the metal protective layer 140 is used as a mask to pattern the photovoltaic layer 130, the photovoltaic layer 130 will also have a protrusion 131 and the protrusion 131 will also have a long strip-shaped through hole 133.

[0137] Please also see Fig.14 and Fig.15 , Fig.14The transparent substrate 110, the transparent front electrode 120, the auxiliary metal layer 170 and the photovoltaic layer 130 are combined into a pattern shape; Fig.15 for Fig.14 Schematic diagram of the E1 region in Figure 1. Fig.14 It can be seen from the figure that the cross-sectional width of the photovoltaic layer 130 in the vertical direction is greater than the cross-sectional width of the transparent front electrode 120 in the vertical direction, so that the photovoltaic layer 130 completely covers the transparent front electrode 120. As required, the difference between the cross-sectional width of the photovoltaic layer 130 in the vertical direction and the cross-sectional width of the transparent front electrode 120 in the vertical direction is greater than or equal to 50 μm, so that after the photovoltaic layer 130 is patterned, the edge of the transparent front electrode 120 in the effective photovoltaic area is completely covered by the photovoltaic layer.

[0138] A back electrode 150 is disposed on the surface of the metal protection layer 140. In this embodiment, the back electrode 150 is made of one or more materials selected from Ag, Al, Cr, Cu, Au, Pt, Mg, Mo, Ti, Sn, conductive polymer, TCO, nanosilver, graphene, and carbon nanotubes. Fig.16 and Fig.17 The back electrode 150 is in a ring shape and has a non-overlapping area 151 and an overlapping area 152 .

[0139] In the non-overlapping region 151 , the cross-sectional width of the back electrode 150 in the vertical direction is less than or equal to the cross-sectional width of the metal protection layer 140 in the vertical direction.

[0140] In the overlapping region 152 , the transparent front electrode 120 has a negative electrode overlapping block 121 . The back electrode 150 extends outward to the negative electrode overlapping block 121 of the transparent front electrode 120 and is electrically connected to the electrode overlapping block 121 .

[0141] in, Fig.17 The cross-sectional shape of the solar cell 100 along the AA direction is Figure 1 The shape of the solar cell 100 is shown.

[0142] It is understandable that the solar cell is not limited to the above embodiments. In another embodiment, the metal protective layer 140 may extend above the negative electrode bridge block 121 of the transparent front electrode 120. In this case, the shape of the metal protective layer 140 is as follows: Fig.13 As shown, the shape of the photovoltaic layer 130 is as follows Fig.10As shown. The metal protective layer 140 also includes a protrusion 141. The protrusion 141 of the metal protective layer 140 covers the negative electrode overlapping block 121 of the transparent front electrode 120. The protrusion 141 of the metal protective layer 140 has a long strip-shaped through hole 143. During the patterning process of the photovoltaic layer 130, the photovoltaic layer 130 at the through hole position of the metal protective layer 140 is also removed to reveal the surface of the negative electrode overlapping block 121 of the transparent front electrode 120. That is, the photovoltaic layer 130 also includes a protrusion 131. The protrusion 131 of the photovoltaic layer 130 covers the negative electrode overlapping block 121 of the transparent front electrode 120. The protrusion 131 of the photovoltaic layer 130 has a long strip-shaped through hole 133. At this time, when the back electrode 150 is covered on the metal protective layer 140, its planar structure schematic diagram is as shown Fig.18 shown. Fig.19 for Fig.18 Schematic diagram of a cross section along the BB direction in FIG. In the process of manufacturing the back electrode 150, the back electrode 150 is electrically connected to the electrode bridge block 121 of the transparent front electrode 120 through the through hole 143. As required, the difference between the cross-sectional width of the metal protective layer 140 in the vertical direction and the cross-sectional width of the transparent front electrode 120 in the vertical direction is greater than or equal to 20 μm.

[0143] In the manufacturing process of the above solar cell 100, the shape of the photovoltaic layer 130 before patterning completely covers the transparent front electrode 120 in the effective power generation area, and its shape is more than 50μm larger than the edge size of the effective power generation area. The shape of the metal protective layer 140 is more than 20 microns larger than the shape of the transparent front electrode 120 in the effective photovoltaic power generation area, so that after the photovoltaic layer 130 is patterned, the edge of the transparent front electrode 120 in the effective photovoltaic area is completely covered by the photovoltaic layer. At the same time, after the back electrode 150 is covered on the metal protective layer 140, the back electrode 150 will not be connected or short-circuited with the transparent front electrode 120 through the metal protective layer 140. The back electrode 150 covers the surface of the metal protective layer 140, and in the non-overlapping area 151, the size of the back electrode 150 is the same as the size of the metal protective layer 140 or is indented in the metal protective layer 140. The back electrode 150 covers the surface of the photovoltaic layer 130 in the positive and negative electrode lead-out regions, and extends to the periphery to be electrically connected to the negative electrode bridge block 121 independently provided in the transparent front electrode 120 to output charges.

[0144] According to needs, the structural design of the metal protective layer 140 can also be: the metal protective layer 140 covers the local positive and negative electrode areas (the power generation area close to the photovoltaic layer 130), and / or the metal protective layer 140 partially covers the overlapping area of ​​the battery. The metal protective layer 140 in the overlapping area is provided with one or more through holes, and the inner diameter or width of the through hole is greater than or equal to 5μm. After the patterning process, the photovoltaic layer 130 in the through hole is completely removed, and then after the film layer of the back electrode 150 is deposited and covered, the effective electrical connection of the positive and negative electrodes of the solar cell is achieved.

[0145] The above manufacturing method is a manufacturing method for a single-junction solar cell. In fact, when the solar cell is a multi-junction series structure, its manufacturing method is similar.

[0146] See also Fig. 20 , a transparent front electrode is arranged on the surface of the transparent substrate. In the multi-junction solar cell, the transparent front electrode 420 is annular in structure as a whole. A positive lead-out terminal and a negative lead-out terminal are arranged on one side of the transparent front electrode 420. As required, the transparent front electrode 420 has an electrode bridging block 421. In the present embodiment, the transparent front electrode 420 includes a first transparent front electrode 422, a second transparent front electrode 423, a third transparent front electrode 424 and a fourth transparent front electrode 425, which respectively correspond to the transparent front electrodes of each junction of the multi-junction solar cell. In the present embodiment, the first transparent front electrode 422 is electrically connected to the positive lead-out terminal. The electrode bridging block 421 is electrically connected to the negative lead-out terminal.

[0147] The portion of the second transparent front electrode 423 close to the first transparent front electrode 422 is protruded outwardly with a first protrusion 4231. The first protrusion 4231 is used to connect to the back electrode of the solar cell with other junctions. In this embodiment, the first protrusion 4231 of the second transparent front electrode 423 is used to electrically connect to the back electrode of the solar cell corresponding to the first transparent front electrode 422.

[0148] The portion of the third transparent front electrode 424 close to the second transparent front electrode 423 is protruded outwardly with a second protrusion 4241. The second protrusion 4241 is used to connect to the back electrode of the solar cell with other junctions. In this embodiment, the second protrusion 4241 of the third transparent front electrode 424 is used to be electrically connected to the back electrode of the solar cell corresponding to the second transparent front electrode 423.

[0149] The portion of the fourth transparent front electrode 425 close to the third transparent front electrode 424 is protruded outwardly with a third protrusion 4251. The third protrusion 4251 is used to connect to the back electrode of the solar cell with other junctions. In this embodiment, the third protrusion 4251 of the fourth transparent front electrode 425 is used to be electrically connected to the back electrode of the solar cell corresponding to the third transparent front electrode 424.

[0150] Before setting the transparent front electrode, an auxiliary metal layer may be set on the surface of the transparent substrate. Alternatively, after the transparent front electrode is manufactured, an auxiliary metal layer may be set on the surface of the transparent front electrode. Fig.21 As shown, the auxiliary metal layer 470 is arranged at the edge area of ​​the transparent front electrode 420. Correspondingly, the auxiliary metal layer 470 is also divided into several parts, which correspond to the various parts of the transparent front electrode 420 one by one. In this embodiment, the auxiliary metal layer 470 includes an electrode bridge block 471. The electrode bridge block 471 of the auxiliary metal layer 470 corresponds to the setting position of the electrode bridge block 421 of the transparent front electrode 420. The auxiliary metal layer 470 includes a first auxiliary metal layer 472, a second auxiliary metal layer 473, a third auxiliary metal layer 474 and a fourth auxiliary metal layer 475. The first auxiliary metal layer 472 is arranged on the lower surface of the first transparent front electrode 422. The second auxiliary metal layer 473 is arranged on the lower surface of the second transparent front electrode 423. The third auxiliary metal layer 474 is arranged on the lower surface of the third transparent front electrode 424. The fourth auxiliary metal layer 475 is arranged on the lower surface of the fourth transparent front electrode 425.

[0151] As required, the second auxiliary metal layer 473 has a first protrusion 4731 protruding outward from a portion close to the first auxiliary metal layer 472. The first protrusion 4731 is used to overlap with the first protrusion 4231 of the second transparent front electrode 423 to enhance the charge collection capability of the second transparent front electrode 423.

[0152] A second protrusion 4741 is protruded outward from a portion of the third auxiliary metal layer 474 close to the second auxiliary metal layer 473. The second protrusion 4741 is used to overlap with the second protrusion 4241 of the third transparent front electrode 424 to enhance the charge collection capability of the third transparent front electrode 424.

[0153] A third protrusion 4751 is protruded outward from a portion of the fourth auxiliary metal layer 475 close to the third auxiliary metal layer 474. The third protrusion 4751 is used to overlap with the third protrusion 4251 of the fourth transparent front electrode 425 to enhance the charge collection capability of the fourth transparent front electrode 425.

[0154] A photovoltaic layer is arranged on the surface of the transparent front electrode, a metal protective layer is arranged on the surface of the photovoltaic layer, and a portion of the photovoltaic layer is removed using the metal protective layer as a mask to produce a photovoltaic layer pattern.

[0155] See also Fig. 22 In this embodiment, the photovoltaic layer 430 includes a first photovoltaic layer 431, a second photovoltaic layer 432, a third photovoltaic layer 433 and a fourth photovoltaic layer 434. The first photovoltaic layer 431 covers the surface of the first transparent front electrode 422. The second photovoltaic layer 432 covers the surface of the second transparent front electrode 423. The third photovoltaic layer 433 covers the surface of the third transparent front electrode 424. The fourth photovoltaic layer 434 covers the surface of the fourth transparent front electrode 425.

[0156] It is understood that the shape of the photovoltaic layer is not limited to the above embodiments. Fig.23 In another embodiment, the photovoltaic layer 430 includes a first photovoltaic layer 431, a second photovoltaic layer 432, a third photovoltaic layer 433 and a fourth photovoltaic layer 434. The first photovoltaic layer 431 covers the surface of the first transparent front electrode 422. The second photovoltaic layer 432 covers the surface of the second transparent front electrode 423. The third photovoltaic layer 433 covers the surface of the third transparent front electrode 424. The fourth photovoltaic layer 434 covers the surface of the fourth transparent front electrode 425.

[0157] Different from the previous embodiment, in this embodiment, a first extension portion 4321 is provided on the outer side of the second photovoltaic layer 432. The first extension portion 4321 is provided at a position corresponding to the first protrusion 4231 of the second transparent front electrode 423. A plurality of through holes 4322 are provided on the first extension portion 4321. The plurality of through holes 4322 on the first extension portion 4321 are used for the back electrodes of solar cells of other junctions to pass through, so that the back electrodes of solar cells of other junctions can be electrically connected to the second transparent front electrode 423 through the plurality of through holes 4322 on the first extension portion 4321.

[0158] Similarly, a second extension portion 4331 is provided on the outer side of the third photovoltaic layer 433. The second extension portion 4331 is provided at a position corresponding to the second protrusion 4241 of the third transparent front electrode 424. A plurality of through holes 4332 are provided on the second extension portion 4331. The plurality of through holes 4332 on the second extension portion 4331 are used for the back electrodes of solar cells of other junctions to pass through, so that the back electrodes of solar cells of other junctions can be electrically connected to the third transparent front electrode 424 through the plurality of through holes 4332 on the second extension portion 4331.

[0159] Similarly, a third extension portion 4341 is disposed on the outer side of the fourth photovoltaic layer 434. The third extension portion 4341 is disposed at a position corresponding to the third protrusion 4251 of the fourth transparent front electrode 425. A plurality of through holes 4342 are disposed on the third extension portion 4341. The plurality of through holes 4342 on the third extension portion 4341 are used for the back electrodes of solar cells of other junctions to pass through, so that the back electrodes of solar cells of other junctions can be electrically connected to the fourth transparent front electrode 425 through the plurality of through holes 4342 on the third extension portion 4341.

[0160] In this embodiment, a fourth extension portion 4343 is provided on the outer side of the fourth photovoltaic layer 434 close to the first photovoltaic layer 431. The setting position of the fourth extension portion 4343 corresponds to the setting position of the negative electrode bridging block 421. A plurality of through holes 4344 are provided on the fourth extension portion 4343. The plurality of through holes 4344 on the fourth extension portion 4343 are used for the back electrode of the solar cell of this junction to pass through, so that the back electrode of the solar cell of this junction can be electrically connected to the negative electrode bridging block 421 through the plurality of through holes 4344 on the fourth extension portion 4343.

[0161] The shape of the through hole is not limited to the above embodiment. Fig.24 In another embodiment, the photovoltaic layer 430 includes a first photovoltaic layer 431, a second photovoltaic layer 432, a third photovoltaic layer 433 and a fourth photovoltaic layer 434. The first photovoltaic layer 431 covers the surface of the first transparent front electrode 422. The second photovoltaic layer 432 covers the surface of the second transparent front electrode 423. The third photovoltaic layer 433 covers the surface of the third transparent front electrode 424. The fourth photovoltaic layer 434 covers the surface of the fourth transparent front electrode 425.

[0162] In this embodiment, a first extension portion 4321 is provided on the outer side of the second photovoltaic layer 432. The first extension portion 4321 is provided at a position corresponding to the first protrusion 4231 of the second transparent front electrode 423. Different from the previous embodiment, a long strip through hole 4323 is provided on the first extension portion 4321. The long strip through hole 4323 on the first extension portion 4321 is used for the back electrode of the solar cell of other junctions to pass through, so that the back electrode of the solar cell of other junctions can be electrically connected to the second transparent front electrode 423 through the long strip through hole 4323 on the first extension portion 4321.

[0163] Similarly, a second extension portion 4331 is provided on the outer side of the third photovoltaic layer 433. The second extension portion 4331 is provided at a position corresponding to the second protrusion 4241 of the third transparent front electrode 424. A long strip through hole 4333 is provided on the second extension portion 4331. The long strip through hole 4333 on the second extension portion 4331 is used for the back electrode of the solar cell of other junctions to pass through, so that the back electrode of the solar cell of other junctions can be electrically connected to the third transparent front electrode 424 through the long strip through hole 4333 on the second extension portion 4331.

[0164] Similarly, a third extension portion 4341 is provided on the outer side of the fourth photovoltaic layer 434. The third extension portion 4341 is provided at a position corresponding to the third protrusion 4251 of the fourth transparent front electrode 425. The third extension portion 4341 is provided with a long strip through hole 4345. The long strip through hole 4345 on the third extension portion 4341 is used for the back electrode of the solar cell of other junctions to pass through, so that the back electrode of the solar cell of other junctions can be electrically connected to the fourth transparent front electrode 425 through the long strip through hole 4345 on the third extension portion 4341.

[0165] In this embodiment, a fourth extension portion 4343 is provided on the outer side of the fourth photovoltaic layer 434 close to the first photovoltaic layer 431. The setting position of the fourth extension portion 4343 corresponds to the setting position of the negative electrode bridging block 421. The fourth extension portion 4343 is provided with a long strip through hole 4346. The long strip through hole 4346 on the fourth extension portion 4343 is used for the back electrode of the solar cell of this junction to pass through, so that the back electrode of the solar cell of this junction can be electrically connected to the negative electrode bridging block 421 through the long strip through hole 4346 on the fourth extension portion 4343.

[0166] See also Fig.25, the metal protective layer 440 is in a circular ring shape as a whole. In this embodiment, the metal protective layer 440 includes a first metal protective layer 441, a second metal protective layer 442, a third metal protective layer 443 and a fourth metal protective layer 444, which respectively correspond to the metal protective layers of each junction of the multi-junction solar cell. In this embodiment, the first metal protective layer 441 covers the first photovoltaic layer 431. During the manufacturing process, the pattern of the first photovoltaic layer 431 is formed by removing the excess photovoltaic layer with the first metal protective layer 441 as a mask. The second metal protective layer 442 covers the second photovoltaic layer 432. During the manufacturing process, the pattern of the second photovoltaic layer 432 is formed by removing the excess photovoltaic layer with the second metal protective layer 442 as a mask. The third metal protective layer 443 covers the third photovoltaic layer 433. During the manufacturing process, the pattern of the third photovoltaic layer 433 is formed by removing the excess photovoltaic layer with the third metal protective layer 443 as a mask. The fourth metal protective layer 444 covers the fourth photovoltaic layer 434. During the manufacturing process, the pattern of the fourth photovoltaic layer 434 is formed by removing the redundant photovoltaic layer using the fourth metal protection layer 444 as a mask.

[0167] It is understood that the shape of the metal protective layer is not limited to the above embodiments. Fig.26 In another embodiment, the metal protective layer 440 includes a first metal protective layer 441, a second metal protective layer 442, a third metal protective layer 443 and a fourth metal protective layer 444, which respectively correspond to the metal protective layers of each junction of the multi-junction solar cell. In this embodiment, the first metal protective layer 441 covers the first photovoltaic layer 431. The second metal protective layer 442 covers the second photovoltaic layer 432. The third metal protective layer 443 covers the third photovoltaic layer 433. The fourth metal protective layer 444 covers the fourth photovoltaic layer 434.

[0168] Different from the previous embodiment, in this embodiment, a first extension portion 4421 is provided on the outer side of the second metal protection layer 442. The first extension portion 4421 is provided at a position corresponding to the first protrusion 4231 of the second transparent front electrode 423. A plurality of through holes 4422 are provided on the first extension portion 4421. The plurality of through holes 4422 on the first extension portion 4421 are used for the back electrodes of solar cells of other junctions to pass through, so that the back electrodes of solar cells of other junctions can be electrically connected to the second transparent front electrode 423 through the plurality of through holes 4422 on the first extension portion 4421.

[0169] Similarly, a second extension portion 4431 is provided on the outer side of the third metal protection layer 443. The second extension portion 4431 is provided at a position corresponding to the second protrusion 4241 of the third transparent front electrode 424. A plurality of through holes 4432 are provided on the second extension portion 4431. The plurality of through holes 4432 on the second extension portion 4431 are used for the back electrodes of solar cells of other junctions to pass through, so that the back electrodes of solar cells of other junctions can be electrically connected to the third transparent front electrode 424 through the plurality of through holes 4432 on the second extension portion 4431.

[0170] Similarly, a third extension portion 4441 is disposed on the outer side of the fourth metal protection layer 444. The third extension portion 4441 is disposed at a position corresponding to the third protrusion 4251 of the fourth transparent front electrode 425. A plurality of through holes 4442 are disposed on the third extension portion 4441. The plurality of through holes 4442 on the third extension portion 4441 are used for the back electrodes of solar cells of other junctions to pass through, so that the back electrodes of solar cells of other junctions can be electrically connected to the fourth transparent front electrode 425 through the plurality of through holes 4442 on the third extension portion 4441.

[0171] In this embodiment, a fourth extension portion 4443 is provided on the outer side of the fourth metal protection layer 444 near the first metal protection layer 441. The fourth extension portion 4443 is provided at a position corresponding to the position of the negative electrode bridging block 421. The fourth extension portion 4443 is provided with a plurality of through holes 4444. The plurality of through holes 4444 on the fourth extension portion 4443 are used for the back electrode of the solar cell of this junction to pass through, so that the back electrode of the solar cell of this junction can be electrically connected to the negative electrode bridging block 421 through the plurality of through holes 4444 on the fourth extension portion 4443.

[0172] The shape of the through hole in the metal protective layer is not limited to the above embodiment. Fig. 27 In another embodiment, the metal protective layer 440 includes a first metal protective layer 441, a second metal protective layer 442, a third metal protective layer 443 and a fourth metal protective layer 444, which respectively correspond to the metal protective layers of each junction of the multi-junction solar cell. In this embodiment, the first metal protective layer 441 covers the first photovoltaic layer 431. The second metal protective layer 442 covers the second photovoltaic layer 432. The third metal protective layer 443 covers the third photovoltaic layer 433. The fourth metal protective layer 444 covers the fourth photovoltaic layer 434.

[0173] In this embodiment, a first extension portion 4421 is provided on the outer side of the second metal protection layer 442. The first extension portion 4421 is provided at a position corresponding to the first protrusion 4231 of the second transparent front electrode 423. A long strip through hole 4423 is provided on the first extension portion 4421. The long strip through hole 4423 on the first extension portion 4421 is used for the back electrode of the solar cell of other junctions to pass through, so that the back electrode of the solar cell of other junctions can be electrically connected to the second transparent front electrode 423 through the long strip through hole 4423 on the first extension portion 4421.

[0174] Similarly, a second extension portion 4431 is provided on the outer side of the third metal protection layer 443. The second extension portion 4431 is provided at a position corresponding to the second protrusion 4241 of the third transparent front electrode 424. A long strip through hole 4433 is provided on the second extension portion 4431. The long strip through hole 4433 on the second extension portion 4431 is used for the back electrode of the solar cell of other junctions to pass through, so that the back electrode of the solar cell of other junctions can be electrically connected to the third transparent front electrode 424 through the long strip through hole 4433 on the second extension portion 4431.

[0175] Similarly, a third extension portion 4441 is provided on the outer side of the fourth metal protection layer 444. The third extension portion 4441 is provided at a position corresponding to the third protrusion 4251 of the fourth transparent front electrode 425. The third extension portion 4441 is provided with a long strip through hole 4445. The long strip through hole 4445 on the third extension portion 4441 is used for the back electrode of the solar cell of other junctions to pass through, so that the back electrode of the solar cell of other junctions can be electrically connected to the fourth transparent front electrode 425 through the long strip through hole 4445 on the third extension portion 4441.

[0176] In this embodiment, a fourth extension portion 4443 is provided on the outer side of the fourth metal protection layer 444 near the first metal protection layer 441. The fourth extension portion 4443 is provided at a position corresponding to the position of the electrode bridge block 421. The fourth extension portion 4443 is provided with a long strip through hole 4446. The long strip through hole 4446 on the fourth extension portion 4443 is used for the back electrode of the solar cell of this junction to pass through, so that the back electrode of the solar cell of this junction can be electrically connected to the negative electrode bridge block 421 through the long strip through hole 4446 on the fourth extension portion 4443.

[0177] Please also see Fig.28 and Fig.29 , Fig.28It is the pattern shape of the transparent substrate 410, the transparent front electrode 420, the auxiliary metal layer / 470 and the photovoltaic layer 430 combined together. Fig.29 for Fig.28 Schematic diagram of the enlarged E2 region in FIG. As can be seen from the figure, the cross-sectional width of the photovoltaic layer 430 in the vertical direction is greater than the cross-sectional width of the transparent front electrode 420 in the vertical direction, so that the photovoltaic layer 430 completely covers the transparent front electrode 420. As required, the difference between the cross-sectional width of the photovoltaic layer 430 in the vertical direction and the cross-sectional width of the transparent front electrode 420 in the vertical direction is greater than or equal to 50 μm, so that after the photovoltaic layer 430 is patterned, the edge of the transparent front electrode 420 in the effective photovoltaic area is completely covered by the photovoltaic layer.

[0178] A back electrode is arranged on the surface of the metal protective layer. Fig.30 and Fig.31 , the back electrode 450 is in a circular ring shape as a whole. In this embodiment, the back electrode 450 includes a first back electrode 451, a second back electrode 452, a third back electrode 453 and a fourth back electrode 454. The first back electrode 451 covers the surface of the first metal protective layer 441. The second back electrode 452 covers the surface of the second metal protective layer 442. The third back electrode 453 covers the surface of the third metal protective layer 443. The fourth back electrode 454 covers the surface of the fourth metal protective layer 444.

[0179] In this embodiment, the first back electrode 451 includes a first overlap portion 4511. The first overlap portion 4511 extends from the outer side of one end of the first back electrode 451 close to the second back electrode 452 to the outer side of the second back electrode 452, thereby forming an elongated strip. The first overlap portion 4511 of the first back electrode 451 is used to be electrically connected to the first protrusion 4231 of the second transparent front electrode 423, so that adjacent single-junction solar cells form a series structure.

[0180] The second back electrode 452 includes a second overlap portion 4521. The second overlap portion 4521 extends from the outer side of one end of the second back electrode 452 close to the third back electrode 453 to the outer side of the third back electrode 453, thereby forming an elongated strip. The second overlap portion 4521 of the second back electrode 452 is used to be electrically connected to the second protrusion 4241 of the third transparent front electrode 424, so that adjacent single-junction solar cells form a series structure.

[0181] The third back electrode 453 includes a third overlapping portion 4531. The third overlapping portion 4531 extends from the outer side of one end of the third back electrode 453 close to the fourth back electrode 454 to the outer side of the fourth back electrode 454, thereby forming an elongated strip shape. The third overlapping portion 4531 of the third back electrode 453 is used to be electrically connected to the third protruding portion 4251 of the fourth transparent front electrode 425, so that adjacent single-junction solar cells form a series structure.

[0182] The fourth back electrode 454 includes a fourth overlap portion 4541. The fourth overlap portion 4541 extends outward from a region of the fourth back electrode 454 close to the negative electrode overlap block 421 and overlaps with the electrode overlap block 421. The fourth overlap portion 4541 of the fourth back electrode 454 is used to be electrically connected to the electrode overlap block 421, thereby being connected to the negative lead-out terminal of the solar cell.

[0183] Fig.33 for Fig.31 Schematic diagram of the cross section of the solar cell along the CC direction. Fig.33 As shown, the solar cell 400 comprises:

[0184] Transparent substrate 410;

[0185] A transparent front electrode 420 is disposed on the surface of the transparent substrate 410;

[0186] A photovoltaic layer 430 is disposed on the surface of the transparent front electrode 420;

[0187] A metal protection layer 440 is disposed on the surface of the photovoltaic layer 430; and

[0188] A back electrode 450 is disposed on the surface of the metal protection layer 440;

[0189] The metal protection layer 440 includes one or more of Ag, Al, Cr, Cu, Au, Pt, Mo, Ti, Sn, and Mg.

[0190] In this embodiment, the metal protective layer 440 does not cover the area where the electrode bridge block 421 is located. When the back electrode 250 is manufactured, one end of the back electrode 250 is covered on the metal protective layer 240 and the other end is covered on the negative electrode bridge block 221.

[0191] In this embodiment, the transparent front electrode 421 has an electrode bridge block 421. When the back electrode 450 is disposed on the surface of the metal protective layer 440, the other end of the back electrode 450 covers the electrode bridge block 421 of the transparent front electrode 420 and is electrically connected to the electrode bridge block 421. As needed, in order to improve the conductivity of the electrode bridge block 421, the auxiliary metal layer 470 is also provided with an electrode bridge block 471. The electrode bridge block 471 is disposed on the lower surface of the electrode bridge block 421 to improve the charge collection capability of the electrode bridge block 421.

[0192] In another embodiment, the metal protection layer 440 covers the area where the electrode bridge block 421 is located. Fig.32 and Fig.34 , at this time, through holes are provided on the metal protective layer 440 and the photovoltaic layer 430. When manufacturing the back electrode 450, one end of the back electrode 450 is covered on the metal protective layer 440, and the other end passes through the through hole and covers the transparent front electrode 420. Specifically, the first overlapping portion 4511 of the first back electrode 451 is electrically connected to the second transparent front electrode 423 through the long strip through hole 4423 on the first extension portion 4421. The second overlapping portion 4521 of the second back electrode 452 is electrically connected to the third transparent front electrode 424 through the long strip through hole 4433 on the second extension portion 4431. The third overlapping portion 4531 of the third back electrode 453 is electrically connected to the fourth transparent front electrode 425 through the long strip through hole 4445 on the third extension portion 4441. The fourth overlapping portion 4541 of the fourth back electrode 454 is electrically connected to the electrode overlapping block 421 through the long strip-shaped through hole 4446 on the fourth extending portion 4443 .

[0193] Fig.34 for Fig.32 Schematic diagram of the cross section of the solar cell along the DD direction. Fig.34 As shown, the solar cell 400 comprises:

[0194] Transparent substrate 410;

[0195] A transparent front electrode 420 is disposed on the surface of the transparent substrate 410;

[0196] A photovoltaic layer 430 is disposed on the surface of the transparent front electrode 420;

[0197] A metal protection layer 440 is disposed on the surface of the photovoltaic layer 430; and

[0198] A back electrode 454 is disposed on the surface of the metal protection layer 440;

[0199] The metal protection layer 440 includes one or more of Ag, Al, Cr, Cu, Au, Pt, Mo, Ti, Sn, and Mg.

[0200] When the solar cell is configured as a multi-junction series structure, the photovoltaic layer 430 of the multi-junction battery can be configured as a continuous filling structure in the sub-region of the multi-junction battery, or as a physically divided independent structure, and its shape completely covers the transparent front electrode 420 in the effective power generation region, and at least expands outward to the edge of the transparent front electrode 420 by more than 50 μm. The shape of the metal protective layer 440 is larger than the transparent front electrode 420, and expands outward by more than 20 microns compared to the shape of the transparent front electrode 420 in the effective photovoltaic power generation region, so that after the photovoltaic layer 430 is patterned, the edge of the transparent front electrode 420 is completely covered by the photovoltaic layer 430. After the back electrode 450 covers the metal protective layer 440, the back electrode 450 will not be connected or short-circuited with the transparent front electrode 420 through the metal protective layer 440. The back electrode 450 covers the surface of the metal protective layer 440, and the size of the back electrode 450 in the non-overlapping region is the same as the size of the metal protective layer 440 or is retracted inward from the metal protective layer 440. The transparent front electrode 420 of the first battery is directly led out to the periphery to form an electrode, and is electrically connected to the transparent front electrode of the second battery by means of the back electrode arranged outside the effective photovoltaic area and extending in different directions, forming a positive and negative electrode series structure. The second battery is electrically connected to the transparent front electrode of the third battery by means of the back electrode arranged outside the effective photovoltaic area and extending in different directions, forming a positive and negative electrode series structure. And so on, the series structure setting of the N-1th battery is completed. The back electrode of the Nth (last) battery covers the ineffective PV photovoltaic layer and extends outward, and is connected to the lap block of the physically separated back electrode lead-out terminal, forming a multi-junction series structure connected end to end.

[0201] The above embodiments are preferred implementation modes of the present application, but the implementation modes of the present application are not limited to the embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present application should be equivalent replacement methods and are 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 metal protective layer, disposed on the surface of the photovoltaic layer; a back electrode, disposed on the surface of the metal protection layer; and An encapsulation layer is arranged on a side of the back electrode away from the metal protection layer; Wherein, the metal protective layer includes one or more of Ag, Al, Cr, Cu, Au, Pt, Mo, Ti, Sn, and Mg.

2. The solar cell according to claim 1, characterized in that The cross-sectional width of the photovoltaic layer in the vertical direction is greater than the cross-sectional width of the transparent front electrode in the vertical direction, so that the photovoltaic layer completely covers the transparent front electrode.

3. The solar cell according to claim 2, characterized in that: Before the photovoltaic layer is patterned, a difference between a cross-sectional width in a vertical direction and a cross-sectional width of the transparent front electrode in a vertical direction is greater than or equal to 50 μm.

4. The solar cell according to claim 3, characterized in that: A difference between a cross-sectional width of the metal protection layer in the vertical direction and a cross-sectional width of the transparent front electrode in the vertical direction is greater than or equal to 20 μm.

5. The solar cell according to claim 4, characterized in that: The back electrode has an overlapping area and a non-overlapping area: In the non-overlapping area, the cross-sectional width of the back electrode in the vertical direction is less than or equal to the cross-sectional width of the metal protection layer in the vertical direction; In the overlapping area, the transparent front electrode has an electrode overlapping block, and the back electrode extends outward to the electrode overlapping block of the transparent front electrode and is electrically connected to the electrode overlapping block.

6. The solar cell according to claim 5, characterized in that The photovoltaic layer and the metal protective layer also cover the electrode bridge block; In the area covering the electrode strapping block, the metal protection layer and the photovoltaic layer have through holes, and the back electrode passes through the through holes to be electrically connected to the electrode strapping block.

7. The solar cell according to any one of claims 1 to 6, characterized in that: Also includes: The auxiliary metal layer is arranged on the upper surface or the lower surface of the transparent front electrode, and the auxiliary metal layer is used to improve the charge collection and conduction capabilities of the transparent front electrode.

8. The solar cell according to claim 7, characterized in that: The auxiliary metal layer includes a main body and an extension portion: The body of the auxiliary metal layer is disposed in an outer edge region of the transparent front electrode; The extension portion of the auxiliary metal layer extends inward from the main body to form a multi-segment line shape or a grid shape.

9. The solar cell according to claim 8, characterized in that The line widths of the main body and the extension portion of the auxiliary metal layer are less than or equal to 20 μm.

10. The solar cell according to claim 8, characterized in that The distance between two adjacent lines of the extension portion of the auxiliary metal layer is less than 1 cm.

11. The solar cell according to any one of claims 1 to 6, characterized in that: Also includes: The first insulating layer is arranged at the outer edge and / or inner edge region of the transparent front electrode and between the transparent front electrode and the photovoltaic layer.

12. The solar cell according to any one of claims 1 to 6, characterized in that: Also includes: The second insulating layer is arranged at the outer edge and / or inner edge region of the photovoltaic layer and between the photovoltaic layer and the metal protective layer.

13. The solar cell according to any one of claims 1 to 6, characterized in that: The solar cell is an organic solar cell, a perovskite solar cell, a nano-quantum dot solar cell or an organic-inorganic hybrid solar cell.

14. The solar cell according to any one of claims 1 to 6, characterized in that: The material for making the back electrode includes one or more of Ag, Al, Cr, Cu, Au, Pt, Mg, Mo, Ti, Sn, conductive polymer, TCO, nanosilver, graphene, and carbon nanotubes.

15. The solar cell according to any one of claims 1 to 6, characterized in that: The packaging layer is made of materials including one or more of an atomic deposition layer, a TFE film packaging layer, a polymer film compounded with a water and oxygen barrier layer, and a metal, glass or quartz substrate coated with an adhesive.

16. A method for manufacturing a solar cell, characterized in that: The following steps are involved: providing a transparent substrate; Disposing a transparent front electrode on the surface of the transparent substrate; Disposing a photovoltaic layer on the surface of the transparent front electrode; Disposing a metal protective layer on the surface of the photovoltaic layer; Using the metal protective layer as a mask to remove part of the photovoltaic layer to produce a photovoltaic layer pattern; Disposing a back electrode on the surface of the metal protective layer; A packaging layer is disposed on a side of the back electrode away from the metal protection layer.

17. The method for manufacturing a solar cell according to claim 16, characterized in that: When the transparent front electrode is provided, an auxiliary metal layer may be provided on the upper surface or the lower surface of the transparent front electrode.

18. The method for manufacturing a solar cell according to claim 16, characterized in that: When the photovoltaic layer is provided, a first insulating layer is first provided on the outer edge and / or inner edge region of the transparent front electrode.

19. A display device, characterized in that: The invention comprises a display and a solar cell as claimed in any one of claims 1 to 15.

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