A stacked solar cell and a method of manufacturing the same

Abstract

The application is suitable for the technical field of solar cells, and provides a laminated solar cell and a manufacturing method thereof. The laminated solar cell comprises a perovskite cell and a crystalline silicon cell which are arranged in a stack. The perovskite cell comprises a first surface which is located on a side of the perovskite cell facing away from the crystalline silicon cell. The crystalline silicon cell comprises a second surface which is located on a side of the crystalline silicon cell facing away from the perovskite cell. The laminated solar cell further comprises a water absorption layer located on the first surface and / or the second surface. In this way, since the water absorption layer is arranged on the first surface and / or the second surface, water molecules in the air can be absorbed by the water absorption layer when the water molecules contact the water absorption layer, so that the damage of the perovskite cell caused by water vapor can be reduced, and the humidity stability of the laminated solar cell can be improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of solar cells, and particularly relates to a laminated solar cell and a manufacturing method thereof. BACKGROUND

[0002] In the related art, the perovskite cell in the laminated solar cell has poor stability. Decomposition of the perovskite material is an irreversible process, and therefore, delaying the decomposition rate of the perovskite cell in the laminated solar cell is the top priority in accelerating the industrialization process. Among many factors affecting the stability of the perovskite cell, humidity has a particularly great impact on the stability of the perovskite cell. When water vapor reaches the surface of the perovskite film, the surface of the perovskite film rapidly decomposes under the combined action of water and oxygen, ultimately leading to a decrease in the performance of the perovskite cell. Based on this, how to improve the humidity stability of the perovskite cell in the laminated solar cell has become a problem to be solved. SUMMARY

[0003] The application provides a laminated solar cell and a manufacturing method thereof, and aims to solve the problem of how to improve the humidity stability of the perovskite cell in the laminated solar cell.

[0004] In a first aspect, the application provides a laminated solar cell, which comprises a perovskite cell and a crystalline silicon cell arranged in a stack, the perovskite cell comprises a first surface, the first surface is located on a side of the perovskite cell away from the crystalline silicon cell, the crystalline silicon cell comprises a second surface, the second surface is located on a side of the crystalline silicon cell away from the perovskite cell; the laminated solar cell further comprises a water absorption layer located on the first surface and / or the second surface.

[0005] Optionally, the thickness of the water absorption layer ranges from 0.01 mm to 1 mm.

[0006] Optionally, the water absorption layer comprises a water absorption resin film.

[0007] Optionally, the water absorption resin film comprises one or more of polyvinyl alcohol, polyoxyethylene, polyacrylate, starch-acrylonitrile graft polymer hydrolysate, starch-acrylic acid copolymer, starch-acrylamide graft polymer, cellulose graft copolymer, cellulose derivative crosslinking product, and the like.

[0008] Optionally, the water absorption resin film has one or more of low molecular weight, medium molecular weight, and high molecular weight.

[0009] In a second aspect, the application provides a manufacturing method of a laminated solar cell, which comprises the following steps:

[0010] Fabricating a stacked silicon cell and a perovskite cell, the perovskite cell comprising a first surface, the first surface being on a side of the perovskite cell facing away from the silicon cell, the silicon cell comprising a second surface, the second surface being on a side of the silicon cell facing away from the perovskite cell;

[0011] Depositing a water absorption layer on the first surface and / or the second surface.

[0012] Optionally, depositing a water absorption layer on the first surface and / or the second surface comprises:

[0013] Applying a raw material solution of the water absorption layer on the first surface and / or the second surface.

[0014] Annealing the stacked solar cell coated with the raw material solution to obtain the water absorption layer.

[0015] Optionally, the raw material solution is applied on the first surface and / or the second surface by a spraying, spin-coating or doctor-blade coating process.

[0016] Optionally, in the step of annealing the stacked solar cell coated with the raw material solution to obtain the water absorption layer, the annealing temperature ranges from 60°C to 80°C.

[0017] In a third aspect, the present application provides a stacked solar cell fabricated by any of the above methods.

[0018] In the stacked solar cell and the fabrication method thereof, the water absorption layer is provided on the first surface and / or the second surface, so that the water molecules in the air are absorbed by the water absorption layer when they contact the water absorption layer, which can reduce the damage of water vapor to the perovskite cell and improve the humidity stability of the stacked solar cell. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a structural schematic diagram of a stacked solar cell of an embodiment of the present application;

[0020] Figure 2 is a structural schematic diagram of a stacked solar cell of an embodiment of the present application;

[0021] Figure 3 is a structural schematic diagram of a stacked solar cell of an embodiment of the present application;

[0022] Figure 4 is a flowchart of a fabrication method of a stacked solar cell of an embodiment of the present application;

[0023] Figure 5 is a flowchart of a fabrication method of a stacked solar cell of an embodiment of the present application;

[0024] Figure 6 is a flowchart of a manufacturing method of a laminated solar cell according to an embodiment of the present application.

[0025] Main element symbol explanation:

[0026] Laminated solar cell 100, perovskite cell 10, first surface 101, crystalline silicon cell 20, second surface 201;

[0027] First electrode 111, antireflection layer 112, first conductive layer 113, first contact layer 114, first perovskite light absorption layer 115, second contact layer 116, HJT cell 210, conductive composite layer 211, first carrier selection layer 212, first passivation layer 213, silicon substrate 214, second passivation layer 215, second carrier selection layer 216, second conductive layer 217, second electrode 218, first water absorption layer 31, second water absorption layer 32;

[0028] Glass substrate layer 121, third conductive layer 122, third contact layer 123, second perovskite light absorption layer 124, fourth contact layer 125, and third electrode 126; PERC cell 220, third water absorption layer 33. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0030] Please refer to Figure 1 , Figure 2 and Figure 3 The laminated solar cell 100 according to an embodiment of the present application includes a perovskite cell 10 and a crystalline silicon cell 20 arranged in a stack, the perovskite cell 10 includes a first surface 101, the first surface 101 is located on a side of the perovskite cell 10 facing away from the crystalline silicon cell 20, the crystalline silicon cell 20 includes a second surface 201, the second surface 201 is located on a side of the crystalline silicon cell 20 facing away from the perovskite cell 10; the laminated solar cell 100 further includes a water absorption layer located on the first surface 101 and / or the second surface 201.

[0031] The laminated solar cell 100 according to an embodiment of the present application, since the water absorption layer is provided on the first surface 101 and / or the second surface 201, when the water molecules in the air contact the water absorption layer, the water molecules will be absorbed by the water absorption layer, which can reduce the damage of water vapor to the perovskite cell 10, and is conducive to improving the humidity stability of the laminated solar cell 100.

[0032] Optionally, the water absorption layer completely covers the first surface 101 and / or the second surface 201. In this way, the water absorption layer has no holes, avoiding water vapor from the holes into the battery, and improving the humidity stability of the stacked solar cell 100.

[0033] Optionally, the thickness of the water absorption layer ranges from 0.01 mm to 1 mm. For example, 0.01 mm, 0.02 mm, 0.05 mm, 0.1 mm, 0.15 mm, 0.2 mm, 0.35 mm, 0.4 mm, 0.5 mm, 0.65 mm, 0.72 mm, 0.85 mm, 0.94 mm, 1 mm. In this way, the thickness of the water absorption layer is in a suitable range, avoiding poor water absorption effect caused by too small thickness, and avoiding high cost caused by too large thickness. Preferably, the thickness of the water absorption layer is 0.5 mm. In this way, the water absorption effect and cost are considered, and the overall effect is the best.

[0034] Optionally, the water absorption layer includes a water absorption resin film. In this way, the water absorption resin film is used as the water absorption layer, and the water absorption effect is good, which is conducive to improving the humidity stability of the battery.

[0035] Specifically, an organic solvent can be used to dissolve the water absorption resin material to form a solution, and deposited on the first surface and / or the second surface to form a water absorption resin film; water can be used to dissolve the water absorption resin material to form a solution, and deposited on the first surface and / or the second surface to form a water absorption resin film; the water absorption resin material can be processed into a film, and then attached to the first surface and / or the second surface to form a water absorption resin film. The specific way of forming the water absorption resin film is not limited here.

[0036] It can be understood that in other embodiments, the water absorption layer can include calcium chloride, aluminum oxide, magnesium sulfate, and other non-resin materials.

[0037] Optionally, the water absorption resin film includes one or more of polyvinyl alcohol, polyoxyethylene, polyacrylate, starch-acrylonitrile graft polymer hydrolysate, starch-acrylic acid copolymer, starch-acrylamide graft polymer, cellulose graft copolymer, cellulose derivative crosslinking material, etc. In this way, a variety of types of water absorption resin films are provided, which can be selected according to the actual production situation.

[0038] For example, the water-absorbing resin film can include polyvinyl alcohol, polyoxyethylene, polyacrylate, starch-acrylonitrile graft polymer hydrolysate, starch-acrylic acid copolymer, starch-acrylamide graft polymer, cellulose graft copolymer, cellulose derivative crosslinking product; for another example, the water-absorbing resin film can include starch-acrylonitrile graft polymer hydrolysate, starch-acrylic acid copolymer, starch-acrylamide graft polymer, cellulose graft copolymer, cellulose derivative crosslinking product; for still another example, the water-absorbing resin film can include polyvinyl alcohol, polyoxyethylene, polyacrylate, starch-acrylonitrile graft polymer hydrolysate.

[0039] Optionally, the water-absorbing resin film has one or more of low molecular weight, medium molecular weight, and high molecular weight. In this way, water-absorbing resin films of various molecular weights are provided, which can be selected according to actual production conditions.

[0040] It can be understood that at present, low molecular weight super absorbent polymer (SAP) is usually dissolved in perovskite precursor solution for doping to improve humidity stability. However, the solubility of low molecular weight super absorbent polymer in perovskite precursor solution is low, and it is easy to cause changes in the morphology of the perovskite light absorption layer. At the same time, a lower content of doping cannot resist a high humidity environment, and is easy to cause decomposition of the perovskite battery, thereby affecting the electrical performance of the perovskite battery.

[0041] In the present embodiment, however, the water-absorbing layer is provided on the first surface 101 and / or the second surface 201 and does not contact the perovskite light absorption layer, and thus does not affect the morphology of the perovskite light absorption layer. Moreover, the water-absorbing layer does not need to be doped in the perovskite precursor solution, and the content of the water-absorbing material in the water-absorbing layer is high, which can resist a high humidity environment.

[0042] Referring to Figure 1 , the crystalline silicon cell 20 includes an HJT cell 210. Referring to Figure 2 and Figure 3 , the crystalline silicon cell 20 includes a PERC cell 220. It can be understood that in other embodiments, the crystalline silicon cell 20 can include a Topcon cell, an IBC cell, an HBC cell, or other types of crystalline silicon solar cells. The specific form of the crystalline silicon cell 20 is not limited herein.

[0043] In Figure 1In the example of FIG. 1, the stacked solar cell 100 is a two-terminal stacked solar cell, the crystalline silicon cell 20 includes the HJT cell 210, the water absorption layer includes the first water absorption layer 31 and the second water absorption layer 32, the first water absorption layer 31 is located on the first surface 101 of the perovskite cell 10, and the second water absorption layer 32 is located on the second surface 201 of the HJT cell 210. In this way, the water vapor cannot enter the interior of the stacked solar cell 100 from both sides, and the effect of preventing water vapor from entering the interior of the cell is better.

[0044] In the example of FIG. 1, the stacked solar cell 100 is a two-terminal stacked solar cell, the crystalline silicon cell 20 includes the HJT cell 210, the water absorption layer includes the first water absorption layer 31 and the second water absorption layer 32, the first water absorption layer 31 is located on the first surface 101 of the perovskite cell 10, and the second water absorption layer 32 is located on the second surface 201 of the HJT cell 210. In this way, the water vapor cannot enter the interior of the stacked solar cell 100 from both sides, and the effect of preventing water vapor from entering the interior of the cell is better. Figure 2 and Figure 3 In the example of FIG. 1, the stacked solar cell 100 is a two-terminal stacked solar cell, the crystalline silicon cell 20 includes the HJT cell 210, the water absorption layer includes the first water absorption layer 31 and the second water absorption layer 32, the first water absorption layer 31 is located on the first surface 101 of the perovskite cell 10, and the second water absorption layer 32 is located on the second surface 201 of the HJT cell 210. In this way, the water vapor cannot enter the interior of the stacked solar cell 100 from both sides, and the effect of preventing water vapor from entering the interior of the cell is better.

[0045] In the example of FIG. 1, the stacked solar cell 100 is a two-terminal stacked solar cell, the crystalline silicon cell 20 includes the HJT cell 210, the water absorption layer includes the first water absorption layer 31 and the second water absorption layer 32, the first water absorption layer 31 is located on the first surface 101 of the perovskite cell 10, and the second water absorption layer 32 is located on the second surface 201 of the HJT cell 210. In this way, the water vapor cannot enter the interior of the stacked solar cell 100 from both sides, and the effect of preventing water vapor from entering the interior of the cell is better. Figure 1 , Figure 2 and Figure 3 In the example of FIG. 1, the stacked solar cell 100 further includes a plurality of third surfaces between the first surface 101 and the second surface 201. The water absorption layer can include a fourth water absorption layer, and the fourth water absorption layer is located on the third surface. In this way, the water vapor cannot enter the interior of the stacked solar cell 100 from the third surface. Specifically, the fourth water absorption layer can be continuously arranged on the third surface. In this way, the fourth water absorption layer has no holes, and the effect of preventing water vapor from entering the interior of the cell is better. Further, the fourth water absorption layer can be continuously arranged with the first water absorption layer 31 located on the first surface 101. In this way, the water vapor cannot enter the interior of the cell from the gap between the fourth water absorption layer and the first water absorption layer 31. Further, the fourth water absorption layer can be continuously arranged with the second water absorption layer 32 located on the second surface 201. In this way, the water vapor cannot enter the interior of the cell from the gap between the fourth water absorption layer and the second water absorption layer 32. Further, the fourth water absorption layer can be continuously arranged with the third water absorption layer 33 located on the second surface 201. In this way, the water vapor cannot enter the interior of the cell from the gap between the fourth water absorption layer and the third water absorption layer 33.

[0046] It can be understood that in other examples, the stacked solar cell 100 can also be provided with a water absorption layer only on the first surface 101. The specific arrangement of the water absorption layer is not limited herein.

[0047] Optionally, a glass cover plate can be arranged on the side of the water absorption layer away from the cell, and the glass cover plate is provided with a glass light trapping structure on the side facing the water absorption layer.

[0048] For example, in the example of FIG. 1, the glass cover plate is provided with a glass light trapping structure on the side facing the water absorption layer. Figure 1In one example, a first glass cover can be provided on the side of the first absorbent layer 31 facing away from the perovskite solar cell 10, and the side of the first glass cover facing the first absorbent layer 31 has a glass light-trapping structure; another example is... Figure 1 In one example, a second glass cover can be provided on the side of the second absorbent layer 32 facing away from the HJT battery 210, and the side of the second glass cover facing the second absorbent layer 32 has a glass light-trapping structure; another example is... Figure 2 and Figure 3 In the example, a third glass cover can be provided on the side of the third absorbent layer 33 away from the PERC battery 220, and the side of the third glass cover facing the third absorbent layer 33 is provided with a glass light trapping structure.

[0049] Thus, the uneven glass light-trapping structure provides space for the expansion of the water-absorbing layer, reducing the probability of component breakage caused by the volume expansion after the water-absorbing layer absorbs water. Furthermore, the glass light-trapping structure increases the absorption of sunlight, raising the battery temperature and increasing the re-evaporation and reabsorption of moisture. It can be understood that the water-absorbing layer can uniformly absorb moisture, thus uniformly increasing its volume. When the battery temperature is too high, moisture will evaporate into the air through the edges of the water-absorbing layer, reducing the moisture content in the battery and effectively draining water.

[0050] Specifically, the light-trapping structure of the glass can be an arc-shaped surface recessed into the glass cover. In this way, the arc-shaped surface is smoother, reducing damage to the absorbent layer.

[0051] Specifically, each curved surface of the glass light-trapping structure can be the same size. This facilitates the fabrication of the glass light-trapping structure.

[0052] The following is about Figure 1 Examples and Figure 2 and Figure 3 The examples are explained and illustrated respectively.

[0053] Please see Figure 1 The perovskite solar cell 10 includes a first electrode 111, an antireflection layer 112, a first conductive layer 113, a first contact layer 114, a first perovskite light-absorbing layer 115, and a second contact layer 116 stacked sequentially.

[0054] Please see Figure 1 The first electrode 111 is located on the side of the first absorbent layer 31 facing the HJT battery 210. Thus, the first absorbent layer 31 is located outside the first electrode 111, covering the first electrode 111 and preventing water vapor from contacting the first electrode 111.

[0055] The first electrode 111 can include a metal electrode. In this way, the first electrode 111 has good electrical conductivity. Specifically, the metal electrode can be made of one or more of silver (Ag), gold (Au), aluminum (Al), copper (Cu), molybdenum (Mo), tungsten (W), nickel (Ni), magnesium (Mg), tin (Sn), and tantalum (Ta). Further, in the case where the metal electrode is made of multiple materials from the foregoing, the metal electrode can include multiple groups, each group of metal electrodes being made of one of the foregoing materials; the metal electrode can be made of an alloy of multiple materials from the foregoing; or part of the metal electrode can be made of an alloy of multiple materials from the foregoing, and the remaining metal electrode can include one or more groups, each group of metal electrodes being made of one of the foregoing materials. Preferably, the metal electrode is a silver electrode. It can be understood that, in other embodiments, the first electrode 111 can include a TCO; or the first electrode 111 can include a metal electrode and a TCO.

[0056] Specifically, the thickness of the first electrode 111 ranges from 70 nm to 85 nm. For example, the thickness is 70 nm, 72 nm, 75 nm, 78 nm, 80 nm, 81 nm, 82 nm, 83 nm, 84 nm, or 85 nm. In this way, the thickness of the first electrode 111 is within an appropriate range, which can avoid the battery from not working properly due to the thickness of the first electrode 111 being too small, and can also avoid the cost being too high due to the thickness of the first electrode 111 being too large. Preferably, the thickness of the first electrode 111 is 80 nm. In this way, the overall effect of ensuring the performance of the battery and reducing the cost is best.

[0057] Specifically, the first electrode 111 can be formed by thermal evaporation. In this way, the first electrode 111 has high purity and high density, and has better electrical conductivity.

[0058] Optionally, the first electrode 111 is multi-layered, and along the direction from the crystalline silicon battery 20 to the perovskite battery 10, the first electrode 111 includes a first electrode layer, a second electrode layer, and a third electrode layer, which have oxygen contents decreasing in turn.

[0059] Further, the thickness of the first electrode layer ranges from 40 nm to 45 nm. For example, the thickness is 40 nm, 41 nm, 42 nm, 43 nm, 44 nm, or 45 nm. In this way, the thickness of the first electrode layer is within an appropriate range, which can avoid poor electrical conductivity due to the thickness being too small, and can also avoid high cost due to the thickness being too large. Preferably, the thickness of the first electrode layer is 42.5 nm. In this way, the overall effect is best.

[0060] Further, the thickness of the second electrode layer ranges from 20nm to 25nm. For example, 20nm, 21nm, 22nm, 23nm, 24nm, 25nm. In this way, the thickness of the second electrode layer is in a suitable range, avoiding poor conductivity caused by too small thickness, and avoiding high cost caused by too large thickness. Preferably, the thickness of the second electrode layer is 22.5nm. In this way, the overall effect is best.

[0061] Further, the thickness of the third electrode layer ranges from 10nm to 15nm. For example, 10nm, 11nm, 12nm, 13nm, 14nm, 15nm. In this way, the thickness of the third electrode layer is in a suitable range, avoiding poor conductivity caused by too small thickness, and avoiding high cost caused by too large thickness. Preferably, the thickness of the third electrode layer is 15nm. In this way, the overall effect is best.

[0062] Specifically, along the direction from the crystalline silicon cell 20 to the perovskite cell 10, the oxygen content of the first electrode layer, the second electrode layer, and the third electrode layer decreases.

[0063] The gas flow ratio of O2 and Ar used by the first electrode layer is (3.6-4.4) / 40. For example, 3.6 / 40, 3.7 / 40, 3.8 / 40, 3.9 / 40, 4 / 40, 4.1 / 40, 4.2 / 40, 4.3 / 40, 4.4 / 40. Preferably, the gas flow ratio of O2 and Ar used by the first electrode layer is 4 / 40. In this way, the gas flow ratio of O2 and Ar is high, and more O2 will reduce the oxygen vacancies in the first electrode layer, while increasing its crystallization performance.

[0064] The gas flow ratio of O2 and Ar used by the second electrode layer is (2.6-3.4) / 40. For example, 2.6 / 40, 2.7 / 40, 2.8 / 40, 2.9 / 40, 3 / 40, 3.1 / 40, 3.2 / 40, 3.3 / 40, 3.4 / 40. Preferably, the gas flow ratio of O2 and Ar used by the second electrode layer is 3 / 40. In this way, the gas flow ratio of O2 and Ar is moderate, while taking into account the crystallization performance, carrier mobility and resistivity.

[0065] The ratio of the gas flow of O2 and Ar used by the third electrode layer is (0.6-1.4) / 40. For example, 0.6 / 40, 0.7 / 40, 0.8 / 40, 0.9 / 40, 1 / 40, 1.1 / 40, 1.2 / 40, 1.3 / 40, 1.4 / 40. Preferably, the ratio of the gas flow of O2 and Ar used by the third electrode layer is 1 / 40. In this way, the ratio of the gas flow of O2 and Ar is low but not too low, which does not affect the crystallinity while making the third conductive film 123 have a higher carrier concentration and migration rate. It can be understood that the ratio of the gas flow of O2 and Ar is too low, for example, 0 / 40, which will affect the crystallinity of the ITO thin film. The appropriate increase in the content of oxygen will not affect the crystallinity, and at the same time, due to the lower oxygen content, there will be a large number of oxygen vacancies in the ITO thin film, which makes the thin film have a higher carrier concentration and migration rate.

[0066] In this way, the first electrode 111 has good crystallization performance and conductivity through the combined effect of the first electrode layer, the second electrode layer, and the third electrode layer.

[0067] Please refer to Figure 1 The anti-reflection layer 112 is located on the side of the first electrode 111 away from the first water-absorbing layer 31. The anti-reflection layer 112 includes a magnesium fluoride film (MgF2) and / or a silicon nitride film (Si3N4). For example, the anti-reflection layer 112 includes a magnesium fluoride film and does not include a silicon nitride film; for example, the anti-reflection layer 112 includes a silicon nitride film and a silicon nitride film; for example, the anti-reflection layer 112 includes a magnesium fluoride film and a silicon nitride film. In this way, the anti-reflection effect is better.

[0068] Specifically, the thickness of the anti-reflection layer 112 ranges from 5nm to 20nm. For example, 5nm, 6nm, 7nm, 8nm, 9nm, 10nm, 11nm, 12nm, 13nm, 14nm, 15nm, 16nm, 17nm, 18nm, 19nm, 20nm. In this way, the thickness of the anti-reflection layer 112 is in a suitable range, thereby ensuring the anti-reflection effect. Preferably, the thickness of the anti-reflection layer 112 is 20nm. In this way, the anti-reflection effect is the best.

[0069] Specifically, the anti-reflection layer 112 can be formed by thermal evaporation. In this way, the anti-reflection layer 112 has high purity and high density, and the anti-reflection effect is better.

[0070] It can be understood that in other embodiments, the anti-reflection layer 112 can also be omitted.

[0071] Please refer to Figure 1The first conductive layer 113 is located on the side of the anti-reflection layer 112 away from the first electrode 111. Specifically, the first conductive layer 113 comprises a transparent conductive oxide (TCO). In this way, the TCO can effectively collect the current of the stacked solar cell 100, ensuring the normal operation of the stacked solar cell 100. Moreover, the TCO has high transmittance and can reduce reflection, which can reduce the loss of sunlight. In this way, it is beneficial to improve the photoelectric conversion efficiency.

[0072] Further, the transparent conductive oxide comprises one or more of fluorine doped tin oxide (FTO), indium zinc oxide (IZO), indium tin oxide (ITO), aluminum doped zinc oxide (AZO), aluminum doped tin oxide (ATO), and indium doped gallium oxide (IGO). Preferably, the first conductive layer 113 comprises IZO.

[0073] Further, the thickness of the first conductive layer 113 ranges from 90 nm to 110 nm. For example, it is 90 nm, 92 nm, 95 nm, 97 nm, 100 nm, 101 nm, 105 nm, 108 nm, or 110 nm. In this way, the thickness of the first conductive layer 113 is within an appropriate range, which can avoid poor conductivity caused by too small thickness, and can also avoid high cost caused by too large thickness. Preferably, the thickness of the first conductive layer 113 is 100 nm. In this way, the overall effect of conductivity and cost reduction is best.

[0074] Further, the first conductive layer 113 can be formed by sputtering. In this way, the quality of the first conductive layer 113 is good, and the preparation efficiency is high.

[0075] Please refer to Figure 1 The first contact layer 114 is located on the side of the first conductive layer 113 away from the anti-reflection layer 112. Specifically, the first contact layer 114 is an electron transport layer, and the first contact layer 114 comprises a BCP film (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline), a tin oxide film (SnOx), and a carbon 60 film (C60) stacked in sequence. In this way, the first contact layer 114 can timely transport the electrons excited by sunlight, avoiding the accumulation of carriers affecting the service life of the stacked solar cell 100. Moreover, this can also block holes or holes, reducing the recombination of holes and electrons.

[0076] Further, the thickness of the BCP film ranges from 1 nm to 10 nm. For example, 1 nm, 2 nm, 3 nm, 4 nm, 5 nm, 6 nm, 7 nm, 8 nm, 9 nm, or 10 nm. In this way, the thickness of the BCP film is in a suitable range, so that the effect of transmitting electrons is better. Preferably, the thickness of the lithium fluoride film is 5 nm. In this way, the effect of transmitting electrons is best.

[0077] Further, the BCP film can be formed by thermal evaporation. In this way, the BCP film has higher purity and higher density, and the effect of transmitting electrons is better.

[0078] Further, the thickness of the tin oxide film ranges from 10 nm to 60 nm. For example, 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, or 60 nm. In this way, the thickness of the tin oxide film is in a suitable range, so that the effect of transmitting electrons is better. Preferably, the thickness of the tin oxide film is 20 nm. In this way, the effect of transmitting electrons is best.

[0079] Further, the tin oxide film can be formed by atomic layer deposition (ALD) or slot-die coating. In this way, the thickness of the tin oxide film can be accurately controlled, and the deposited tin oxide film can be more uniform.

[0080] It can be understood that in other embodiments, the first contact layer 114 is an electron transport layer, and the first contact layer 114 can include titanium oxide (TiO2), zinc oxide (ZnO), or tin oxide (SnO2). It can be understood that in the case where the first contact layer 114 is an electron transport layer, the second contact layer 116 is a hole transport layer. In other embodiments, the first contact layer 114 can be a hole transport layer, and the second contact layer 116 can be an electron transport layer.

[0081] Further, the thickness of the carbon 60 film ranges from 10 nm to 80 nm. For example, 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, or 80 nm. In this way, the thickness of the carbon 60 film is in a suitable range, so that the effect of transmitting electrons is better. Preferably, the thickness of the carbon 60 film is 60 nm. In this way, the effect of transmitting electrons is best.

[0082] Further, the carbon 60 film can be formed by thermal evaporation. In this way, the carbon 60 film has higher purity and higher density, and the effect of transmitting electrons is better.

[0083] Please refer to Figure 1The first perovskite light absorption layer 115 is arranged on the side of the first contact layer 114 away from the first conductive layer 113. Specifically, the thickness of the first perovskite light absorption layer 115 ranges from 400 nm to 500 nm. For example, the thickness is 400 nm, 410 nm, 420 nm, 430 nm, 450 nm, 460 nm, 470 nm, 480 nm, 490 nm, or 500 nm. In this way, the first perovskite light absorption layer 115 is within the appropriate range, so that the light absorption effect of the first perovskite light absorption layer 115 is better. Preferably, the thickness of the first perovskite light absorption layer 115 is 450 nm. In this way, the light absorption effect of the first perovskite light absorption layer 115 is best.

[0084] Specifically, the crystal structure of the material of the first perovskite light absorption layer 115 is ABX3 type, A is one or more of Cs + , CH(NH2)2 + , CH3NH3 + , and C(NH2)3 + , B is at least one of Pb 2+ and Sn 2+ , and X is one or more of Br - , I - , and Cl - . In this way, the light absorption effect of the first perovskite light absorption layer 115 is better, which is conducive to improving the photoelectric conversion efficiency.

[0085] For example, A is Cs + , B is Pb 2+ , and X is Br - ; for another example, A is Cs + and CH(NH2)2 + , B is Pb 2+ , and X is Br - ; for yet another example, A is Cs + , B is Pb 2+ and Sn 2+ , and X is Br - ; for example, A is Cs + , B is Pb 2+ , and X is Br - and I - ; for another example, A is CH3NH3 + and C(NH2)3 + , B is Pb 2+ , and X is I - and Cl - ; for yet another example, A is Cs + , CH(NH2)2 + , CH3NH3 + , and C(NH2)3 + , B is Pb2+ and Sn 2+ X is Br-, I- and Cl-.

[0086] Specifically, the perovskite precursor solution is prepared by dissolving lead iodide (PbI2), CsI, CH3NH3I, CH(NH2)2I and CH3NH3Br in dimethyl sulfoxide (DMSO) and N,N dimethylformamide (DMF) at 70°C overnight. The precursor solution is deposited on the second contact layer 116 by slot coating, and the first perovskite light absorption layer 115 is formed after vacuum-assisted crystallization annealing.

[0087] Further, the concentration of the perovskite precursor solution is 0.8-1.5M.

[0088] Further, the first perovskite light absorption layer 115 can be obtained by annealing at 150°C for 20min. The band gap of the first perovskite light absorption layer 115 is 1.58-1.72eV, the perovskite grain size is 4um, and the effective thickness of the perovskite is 400nm.

[0089] Referring to Figure 1 The second contact layer 116 is arranged on the side of the first perovskite light absorption layer 115 away from the first contact layer 114. Specifically, the second contact layer 116 is a hole transport layer, and the hole transport layer includes one or more of a NiOx film, a Spiro-oMeTad film, a CuSCN film and a PTAA film. For example, the hole transport layer includes a NiOx film; for another example, the hole transport layer includes a NiOx film and a PTAA film; for yet another example, the hole transport layer includes a NiOx film, a Spiro-oMeTad film, a CuSCN film and a PTAA film. In this way, the holes excited by sunlight can be timely transported through the second contact layer 116, avoiding the accumulation of holes to affect the service life of the tandem solar cell 100. Moreover, this can also block electrons and reduce hole and electron recombination.

[0090] Specifically, the thickness of the second contact layer 116 ranges from 10nm to 100nm. For example, the thickness is 10nm, 20nm, 30nm, 40nm, 50nm, 60nm, 70nm, 80nm, 90nm or 100nm. Preferably, the thickness of the second contact layer 116 is 20nm.

[0091] Specifically, the second contact layer 116 can be made by physical vapor deposition (PVD). In this way, the deposition speed is fast, the hole transport layer deposited has fewer pinholes and better quality.

[0092] Referring to Figure 1The HJT cell 210 includes a conductive recombination layer 211, a first carrier selection layer 212, a first passivation layer 213, a silicon substrate 214, a second passivation layer 215, a second carrier selection layer 216, a second conductive layer 217, and a second electrode 218.

[0093] Referring to Figure 1 The conductive recombination layer 211 is disposed on the side of the second contact layer 116 away from the first perovskite light absorption layer 115. Specifically, the conductive recombination layer 211 includes a transparent conductive oxide (TCO). In this way, the majority carriers of the perovskite cell 10 and the minority carriers of the crystalline silicon cell 20 can be recombined, or the minority carriers of the perovskite cell 10 and the majority carriers of the crystalline silicon cell 20 can be recombined to realize the transmission of the carriers of the two-end stacked cell.

[0094] Further, the conductive recombination layer 211 includes one or more of fluorine doped tin oxide (FTO), indium zinc oxide (IZO), indium tin oxide (ITO), aluminum doped zinc oxide (AZO), aluminum doped tin oxide (ATO), indium doped gallium oxide (FTO), and microcrystalline silicon. Preferably, the conductive recombination layer 211 is ITO.

[0095] Further, the thickness of the conductive recombination layer 211 ranges from 10 nm to 80 nm. For example, the thickness is 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, or 80 nm. In this way, the thickness of the conductive recombination layer is within an appropriate range, and the conductive effect is good. Preferably, the thickness of the conductive recombination layer 211 is 10 nm. In this way, the conductive effect is best.

[0096] Further, the conductive recombination layer 211 is made by a physical vapor deposition (PVD) method. In this way, the conductive recombination layer 211 is uniform and dense, and has good quality.

[0097] Further, the conductive recombination layer 211 can include three layers, i.e., a first recombination layer, a second recombination layer, and a third recombination layer, in order of decreasing oxygen content from the crystalline silicon cell 20 to the perovskite cell 10.

[0098] The ratio of the gas flow of O2 and Ar used in the first composite layer is (3.6-4.4) / 40. For example, 3.6 / 40, 3.7 / 40, 3.8 / 40, 3.9 / 40, 4 / 40, 4.1 / 40, 4.2 / 40, 4.3 / 40, 4.4 / 40. Preferably, the ratio of the gas flow of O2 and Ar used in the first composite layer is 4 / 40. In this way, the ratio of the gas flow of O2 and Ar is high, and more O2 can reduce the oxygen vacancies in the first composite layer, while increasing its crystallization performance.

[0099] The ratio of the gas flow of O2 and Ar used in the second composite layer is (2.6-3.4) / 40. For example, 2.6 / 40, 2.7 / 40, 2.8 / 40, 2.9 / 40, 3 / 40, 3.1 / 40, 3.2 / 40, 3.3 / 40, 3.4 / 40. Preferably, the ratio of the gas flow of O2 and Ar used in the second composite layer is 3 / 40. In this way, the ratio of the gas flow of O2 and Ar is moderate, while taking into account the crystallization performance, carrier mobility and resistivity.

[0100] It can be understood that the ratio of the gas flow of O2 and Ar is too low, for example, 0 / 40, which will affect the crystallinity of the ITO thin film. Appropriate increase in the content of oxygen will not affect its crystallinity, and the lower oxygen content will cause a large number of oxygen vacancies in the ITO thin film, resulting in a high carrier concentration and migration rate of the thin film.

[0101] In this way, the first composite layer, the second composite layer and the third composite layer have a complex effect, so that the conductive composite layer 211 has good crystallization performance and conductive performance.

[0102] Please refer to Figure 1 The first carrier selection layer 212 is provided on the side of the conductive composite layer 211 away from the second contact layer 116. Specifically, the first carrier selection layer 212 is an electron selection layer. It can be understood that in other embodiments, when the first carrier selection layer 212 is a hole selection layer, the second carrier selection layer 216 is an electron selection layer.

[0103] Further, the first carrier selection layer 212 includes an N-type hydrogenated amorphous silicon film. In this way, the interface charge can be extracted and transmitted by the electron selection layer.

[0104] Further, the thickness of the first carrier selection layer 212 ranges from 5 nm to 7 nm. For example, the thickness is 5 nm, 5.1 nm, 5.5 nm, 5.8 nm, 6 nm, 6.2 nm, 6.5 nm, 6.9 nm, or 7 nm. In this way, the thickness of the first carrier selection layer 212 is in a suitable range, so as to better take charge of the extraction and transmission of interface charges. Preferably, the thickness of the first carrier selection layer 212 is 6 nm. In this way, the first carrier selection layer 212 has the best effect on the extraction and transmission of interface charges.

[0105] Specifically, the first carrier selection layer 212 is formed by continuous deposition using a PECVD method. In this way, the deposition speed is fast, and the quality of the deposited first carrier selection layer 212 is good.

[0106] Referring to Figure 1 , the first passivation layer 213 is arranged on the side of the first carrier selection layer 212 away from the conductive composite layer 211. Specifically, the first passivation layer 213 includes an intrinsic hydrogenated amorphous silicon film. In this way, the first passivation layer 213 is formed, which can reduce recombination, thereby improving photoelectric conversion efficiency.

[0107] Further, the thickness of the first passivation layer 213 ranges from 7 nm to 9 nm. For example, the thickness is 7 nm, 7.1 nm, 7.5 nm, 7.8 nm, 8 nm, 8.2 nm, 8.5 nm, 8.9 nm, or 9 nm. In this way, the thickness of the first passivation layer 213 is in a suitable range, so as to better perform passivation. Preferably, the thickness of the first passivation layer 213 is 8 nm. In this way, the passivation effect is the best.

[0108] Specifically, the first passivation layer 213 is formed by continuous deposition on the silicon substrate 214 using a PECVD method. In this way, the deposition speed is fast, and the quality of the deposited first passivation layer 213 is good.

[0109] Referring to Figure 1 , the silicon substrate 214 is arranged on the side of the first passivation layer 213 away from the first carrier selection layer 212. Specifically, the silicon substrate 214 is an N-type silicon substrate. Further, the N-type silicon substrate can be an N-type polycrystalline substrate or an N-type single crystal substrate. It can be understood that, in other embodiments, the silicon substrate 214 can also be a P-type silicon substrate, such as a P-type polycrystalline substrate or a P-type single crystal substrate.

[0110] Specifically, the surface of the silicon substrate 214 can be formed with a light-trapping structure. In this way, the reflection of sunlight can be reduced, which is conducive to improving photoelectric conversion efficiency.

[0111] Further, the light-trapping structure can be in a pyramid shape, and the height thereof can range from 1 μm to 3 μm. For example, the height can be 1 μm, 1.1 μm, 1.5 μm, 1.8 μm, 2 μm, 2.2 μm, 2.5 μm, 2.9 μm, or 3 μm. In this way, the height of the light-trapping structure is within a suitable range, so that the light-trapping structure has a better antireflection effect. Preferably, the height of the light-trapping structure is 2 μm.

[0112] Further, the silicon substrate 214 can be textured by using sodium hydroxide or potassium hydroxide. In this way, the light-trapping structure can be formed on the silicon substrate 214.

[0113] Further, the silicon substrate 214 after texturing can be cleaned by using RCA1 and RCA2. Further, RCA1 includes hydrogen peroxide, ammonia, and deionized water, and the volume ratio of the hydrogen peroxide, the ammonia, and the deionized water is 1:1:5. Further, RCA2 includes hydrochloric acid, ammonia, and deionized water, and the volume ratio of the hydrochloric acid, the ammonia, and the deionized water is 1:1:6. In this way, the silicon substrate 214 after texturing can be cleaned, so that the residual alkali solution does not affect subsequent manufacturing.

[0114] Further, the silicon substrate 214 can be cleaned again by using hydrogen fluoride (HF). Further, the concentration of the hydrogen fluoride is 5%. In this way, the oxide layer on the surface of the silicon substrate 214 can be removed, so that the oxide layer does not interfere with subsequent manufacturing.

[0115] Referring to FIG. 2, Figure 1 The second passivation layer 215 is arranged on the side of the silicon substrate 214 away from the first passivation layer 213. Specifically, the second passivation layer 215 includes an intrinsic hydrogenated amorphous silicon film. In this way, the recombination can be reduced, so that the photoelectric conversion efficiency is improved.

[0116] Further, the thickness of the second passivation layer 215 can range from 7 nm to 9 nm. For example, the thickness can be 7 nm, 7.1 nm, 7.5 nm, 7.8 nm, 8 nm, 8.2 nm, 8.5 nm, 8.9 nm, or 9 nm. In this way, the thickness of the second passivation layer 215 is within a suitable range, so that the passivation is better. Preferably, the thickness of the second passivation layer 215 is 8 nm. In this way, the passivation effect is best.

[0117] Specifically, the second passivation layer 215 can be continuously deposited on the silicon substrate 214 by using the PECVD method. In this way, the deposition speed is fast, and the quality of the deposited second passivation layer 215 is good.

[0118] Referring to FIG. 2, Figure 1The second carrier selection layer 216 is disposed on the side of the second passivation layer 215 away from the silicon substrate 214. Specifically, the second carrier selection layer 216 is a hole selection layer. It can be understood that in other embodiments, the first carrier selection layer 212 is an electron selection layer, and the second carrier selection layer 216 is a hole selection layer.

[0119] Further, the second carrier selection layer 216 includes a P-type hydrogenated amorphous silicon film. In this way, the interface charge can be extracted and transported by the second carrier selection layer 216.

[0120] Further, the thickness of the second carrier selection layer 216 ranges from 12 nm to 14 nm. For example, 12 nm, 12.1 nm, 12.5 nm, 12.8 nm, 13 nm, 13.2 nm, 13.5 nm, 13.9 nm, 14 nm. In this way, the thickness of the second carrier selection layer 216 is in a suitable range, so as to better take charge of the extraction and transport of the interface charge. Preferably, the thickness of the second carrier selection layer 216 is 13 nm. In this way, the second carrier selection layer 216 has the best effect on the extraction and transport of the interface charge.

[0121] Specifically, the second carrier selection layer 216 can be continuously deposited by a PECVD method. In this way, the deposition speed is fast, and the quality of the deposited second carrier selection layer 216 is good.

[0122] Please refer to Figure 1 The second conductive layer 217 is disposed on the side of the second carrier selection layer 216 away from the second passivation layer 215. Specifically, the second conductive layer 217 includes a transparent conductive oxide (TCO). In this way, the TCO can effectively collect the current of the stacked solar cell 100, ensuring the normal operation of the stacked solar cell 100. Moreover, the TCO has high transmittance and can reduce reflection, which can reduce the loss of sunlight. In this way, it is beneficial to improve the photoelectric conversion efficiency.

[0123] Further, the transparent conductive oxide includes one or more of fluorine doped tin oxide (FTO), indium zinc oxide (IZO), indium tin oxide (ITO), aluminum doped zinc oxide (AZO), aluminum doped tin oxide (ATO), and indium doped gallium oxide (IGO). Preferably, the second conductive layer 217 includes ITO.

[0124] Further, the thickness of the second conductive layer 217 ranges from 140 nm to 160 nm. For example, 140 nm, 142 nm, 145 nm, 147 nm, 150 nm, 151 nm, 155 nm, 158 nm, 160 nm. In this way, the thickness of the second conductive layer 217 is in a suitable range, which can avoid poor conductivity caused by too small thickness, and can also avoid high cost caused by too large thickness. Preferably, the thickness of the second conductive layer 217 is 150 nm. In this way, the overall effect of the best conductivity and cost reduction is achieved.

[0125] Specifically, the second conductive layer 217 can be formed by PECVD. In this way, the deposition speed is fast, the deposited second conductive layer 217 has fewer pinholes, and the quality is better.

[0126] Referring to Figure 2 The second electrode 218 is arranged on the side of the second conductive layer 217 away from the second carrier selection layer 216. The second electrode 218 can include a metal electrode. In this way, the second electrode 218 has good conductivity.

[0127] Specifically, the metal electrode can be made of one or more of silver (Ag), gold (Au), aluminum (Al), copper (Cu), molybdenum (Mo), tungsten (W), nickel (Ni), magnesium (Mg), tin (Sn), and tantalum (Ta). Further, in the case where the metal electrode is made of multiple materials from the foregoing materials, the metal electrode can include multiple groups, each group of metal electrodes being made of one of the foregoing materials; the metal electrode can be made of an alloy of multiple materials from the foregoing materials; or part of the metal electrode can be made of an alloy of multiple materials from the foregoing materials, and the remaining metal electrode includes one or more groups, each group of metal electrodes being made of one of the foregoing materials. Preferably, the metal electrode is a silver electrode.

[0128] Specifically, the thickness of the second electrode 218 ranges from 40 nm to 60 nm. For example, 40 nm, 50 nm, 60 nm. In this way, the thickness of the second electrode 218 is in a suitable range, which can avoid the battery from not working properly due to the thickness of the second electrode 218 being too small, and can also avoid high cost caused by the thickness of the second electrode 218 being too large. Preferably, the thickness of the second electrode 218 is 60 nm. In this way, the overall effect of the best battery performance and cost reduction is achieved.

[0129] Specifically, the second electrode 218 can be formed by PECVD. In this way, the deposition speed is fast, the deposited second electrode 218 has fewer pinholes, and the conductivity is better.

[0130] Referring to Figure 3 and Figure 2The perovskite battery 10 comprises, in sequence, a glass substrate layer 121, a third conductive layer 122, a third contact layer 123, a second perovskite light absorption layer 124, a fourth contact layer 125, and a third electrode 126.

[0131] Referring to Figure 3 and Figure 2 The glass substrate layer 121 can comprise a transparent glass substrate. Specifically, the transmittance of the glass substrate layer 121 can be greater than 90%. For example, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 100%. In this way, the glass substrate has high light transmittance, which can allow more sunlight to enter the perovskite battery 10, thereby improving the photoelectric conversion efficiency.

[0132] Specifically, the glass substrate layer 121 comprises one or more of float glass, embossed glass, tempered glass, anti-reflection glass, PET, PEN, PMMA. In this way, various forms of glass substrate layer 121 are provided, which facilitates selection according to actual production conditions.

[0133] For example, the glass substrate layer 121 comprises float glass; for another example, the glass substrate layer 121 comprises float glass, embossed glass and tempered glass; for another example, the glass substrate layer 121 comprises anti-reflection glass, PET, PEN, PMMA. The specific form of the glass substrate layer 121 is not limited herein.

[0134] Note that conductive glass can be directly used to replace the glass substrate layer 121 and the third conductive layer 122.

[0135] Referring to Figure 3 and Figure 2 The third conductive layer 122 is located on the side of the glass substrate layer 121 facing the PERC battery 220. Specifically, the glass substrate layer 121 on which the third conductive layer 122 is deposited can be cleaned. Further, the glass substrate layer 121 after ultrasonic cleaning can be sequentially cleaned with detergent, deionized water, acetone and ethanol; the glass substrate layer 121 after high-purity nitrogen blowing can be cleaned with an oxygen plasma cleaning machine. In this way, the glass substrate layer 121 on which the third conductive layer 122 is deposited is clean, avoiding the influence of impurities on subsequent preparation.

[0136] Further, the ultrasonic cleaning time ranges from 15 min to 25 min, for example, 15 min, 16 min, 17 min, 18 min, 19 min, 20 min, 21 min, 22 min, 23 min, 24 min, 25 min. Preferably, the ultrasonic cleaning time is 20 min. In this way, the ultrasonic cleaning effect is better.

[0137] Further, the oxygen plasma cleaning time ranges from 5 to 15 minutes. For example, 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, 10 minutes, 11 minutes, 12 minutes, 13 minutes, 14 minutes, 15 minutes. Preferably, the oxygen plasma cleaning time is 10 minutes. In this way, the effect of the oxygen plasma cleaning is better.

[0138] For other explanations of the third conductive layer 122, please refer to the previous explanations of the first conductive layer 113, which will not be repeated here to avoid redundancy.

[0139] Please refer to Figure 3 and Figure 2 The third contact layer 123 is located on the side of the third conductive layer 122 facing the PERC cell 220. Specifically, the third contact layer 123 is an electron transport layer. In this way, the electrons excited by sunlight can be timely transported through the third contact layer 123, avoiding the accumulation of electrons affecting the service life of the tandem solar cell 100. Moreover, this can also block holes and reduce hole and electron recombination.

[0140] It can be understood that in the case where the third contact layer 123 is an electron transport layer, the fourth contact layer 125 is a hole transport layer. In other embodiments, the third contact layer 123 can be a hole transport layer, and the fourth contact layer 125 can be an electron transport layer.

[0141] Specifically, the thickness of the third contact layer 123 ranges from 10 nm to 100 nm. For example, 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm. In this way, the thickness of the third contact layer 123 is in a suitable range, so that the effect of transporting carriers is better. Preferably, the thickness of the third contact layer 123 is 20 nm. In this way, the effect of transporting carriers is best.

[0142] Specifically, the third contact layer 123 can include one or more of titanium oxide (TiO2), zinc oxide (ZnO), zinc stannate (ZnSnO4), or tin oxide (SnO2).

[0143] Further, the third contact layer 123 includes a SnO2 layer. The SnO2 dispersion liquid and deionized water can be mixed in a volume ratio of 1:7 to obtain a SnO2 precursor solution; then deposited on the third conductive layer 122 by slot coating to obtain the SnO2 layer. In this way, the third contact layer 123 can be conveniently and efficiently made.

[0144] Please refer to Figure 3 and Figure 2The second perovskite light absorption layer 124 is located on the side of the third contact layer 123 facing the PERC cell 220. The crystal structure of the second perovskite light absorption layer 124 can refer to the foregoing, and will not be described here again to avoid redundancy.

[0145] Specifically, the thickness of the second perovskite light absorption layer 124 ranges from 350 nm to 500 nm. For example, 350 nm, 351 nm, 355 nm, 360 nm, 375 nm, 400 nm, 421 nm, 450 nm, 485 nm, or 500 nm. In this way, the thickness of the second perovskite light absorption layer 124 is in a suitable range, so that the light absorption effect is better. Preferably, the thickness of the second perovskite light absorption layer 124 is 450 nm.

[0146] Specifically, the color of the second perovskite light absorption layer 124 can be black.

[0147] Specifically, a perovskite preparation solution can be configured; the solution is coated on the third contact layer 123 to obtain a perovskite wet film layer; and the perovskite wet film layer is subjected to annealing treatment to form the second perovskite light absorption layer 124. In this way, the second perovskite light absorption layer 124 can be conveniently and efficiently formed.

[0148] Further, the perovskite preparation solution can be a solution of CH3NH3I and PbI2 dissolved in DMF and DMSO.

[0149] Further, the molar ratio of CH3NH3I and PbI2 ranges from 1:1.005 to 1:1.015. For example, 1:1.005, 1:1.006, 1:1.007, 1:1.008, 1:1.009, 1:1.01, 1:1.011, 1:1.012, 1:1.013, 1:1.014, or 1:1.015. Preferably, the molar ratio of CH3NH3I and PbI2 is 1:1.01.

[0150] Further, the volume ratio of DMF and DMSO is 3:6.5-7.5. For example, 3:6.5, 3:6.6, 3:6.7, 3:6.8, 3:6.9, 3:7, 3:7.1, 3:7.2, 3:7.3, 3:7.4, or 3:7.5. Preferably, the volume ratio of DMF and DMSO is 3:7.

[0151] Further, after dissolving CH3NH3I and PbI2 in the solution of DMF and DMSO, the solution can be stirred. In this way, CH3NH3I and PbI2 are fully dissolved, which is conducive to improving the quality of the second perovskite light absorption layer 124.

[0152] Further, the solution is stirred for 1.8-2.2 hours. For example, 1.8 hours, 1.9 hours, 2.0 hours, 2.1 hours, or 2.2 hours. In this way, the solution is stirred for an appropriate time, so that CH3NH3I and PbI2are fully dissolved. Preferably, the solution is stirred for 2 hours.

[0153] Further, the solution is stirred at a temperature of 65-75 degrees Celsius. For example, 65 degrees Celsius, 66 degrees Celsius, 67 degrees Celsius, 68 degrees Celsius, 69 degrees Celsius, 70 degrees Celsius, 71 degrees Celsius, 72 degrees Celsius, 73 degrees Celsius, 74 degrees Celsius, or 75 degrees Celsius. In this way, the solution is stirred at an appropriate temperature, so that CH3NH3I and PbI2are fully dissolved. Preferably, the solution is stirred at a temperature of 70 degrees Celsius.

[0154] Further, the solution can be coated on the third contact layer 123 by a slot coating process. In this way, the coating speed is faster, and the perovskite wet film layer has fewer defects.

[0155] Further, the substrate coated with the perovskite wet film layer can be heated and dried for 8-12 minutes. For example, 8 minutes, 9 minutes, 10 minutes, 11 minutes, or 12 minutes. In this way, the perovskite wet film layer is made into the second perovskite light absorption layer 124. Preferably, the substrate is heated and dried for 10 minutes.

[0156] Referring to Figure 3 and Figure 2 , the fourth contact layer 125 is located on the side of the second perovskite light absorption layer 124 facing the PERC cell 220. Specifically, the fourth contact layer 125 is a hole transport layer, and the hole transport layer includes one or more of a NiOx film, a Spiro-oMeTad film, a CuSCN film, and a PTAA film. Preferably, the hole transport layer includes a Spiro-oMeTad film.

[0157] Specifically, the fourth contact layer 125 has a thickness of 10-100 nanometers. For example, 10 nanometers, 15 nanometers, 20 nanometers, 33 nanometers, 54 nanometers, 65 nanometers, 80 nanometers, 95 nanometers, or 100 nanometers. In this way, the fourth contact layer 125 has an appropriate thickness, so that the effect of transporting carriers is better. Preferably, the fourth contact layer 125 has a thickness of 15 nanometers.

[0158] Specifically, a wet film layer of the fourth contact layer 125 can be coated on the second perovskite light absorption layer 124, and then the wet film layer of the fourth contact layer 125 is heated and dried. In this way, the fourth contact layer 125 can be conveniently and efficiently prepared.

[0159] Further, the wet film layer of the fourth contact layer 125 can be a Spiro-oMeTad wet film.

[0160] Further, the wet film layer of the fourth contact layer 125 can be coated on the second perovskite light absorbing layer 124 by using a slot coating process. In this way, the coating speed is faster, and the wet film layer of the fourth contact layer 125 has fewer defects.

[0161] Further, the substrate coated with the wet film layer of the fourth contact layer 125 can be heated and dried for 8-12 min. For example, 8 min, 9 min, 10 min, 11 min, 12 min. In this way, the wet film layer of the fourth contact layer 125 is made into the fourth contact layer 125. Preferably, the heating and drying time is 10 min.

[0162] Please refer to Figure 3 and Figure 4 The third electrode 126 is located on the side of the fourth contact layer 125 facing the PERC cell 220.

[0163] Specifically, the thickness of the third electrode 126 ranges from 20 nm to 80 nm. For example, 20 nm, 21 nm, 30 nm, 48 nm, 52 nm, 70 nm, 75 nm, 79 nm, 80 nm. In this way, the thickness of the third electrode 126 is within a suitable range, making the conductive effect better. Preferably, the thickness of the third electrode 126 is 70 nm.

[0164] In this embodiment, the third electrode 126 is ITO. It can be understood that in other embodiments, the third electrode 126 can be other TCOs. For explanations and descriptions of this part, please refer to the foregoing, and to avoid redundancy, they will not be repeated here.

[0165] It can be understood that in other embodiments, the third electrode 126 can include a metal electrode. Specifically, the metal electrode can be made of one or more of silver (Ag), gold (Au), aluminum (Al), copper (Cu), molybdenum (Mo), tungsten (W), nickel (Ni), magnesium (Mg), tin (Sn), and tantalum (Ta). Further, in the case where the metal electrode is made of multiple materials from the foregoing, the metal electrode can include multiple groups, each group of metal electrodes being made of one of the foregoing materials; the metal electrode can be made of an alloy of multiple materials from the foregoing; or part of the metal electrode can be made of an alloy of multiple materials from the foregoing, and the remaining metal electrode includes one or more groups, each group of metal electrodes being made of one of the foregoing materials. Preferably, the metal electrode is a silver electrode.

[0166] Please note that the third electrode 126 can include a metal electrode and a TCO.

[0167] Specifically, sputtering of the third electrode 126 on the fourth contact layer 125 can be started when the vacuum degree of the chamber drops below a preset vacuum degree threshold. Further, the preset vacuum degree threshold ranges from 4.5 x 10-4 Pa-5.5x10 -4 Pa. For example, 4.5x10 -4 Pa, 4.6x10 -4 Pa, 4.7x10 -4 Pa, 4.8x10 -4 Pa, 4.9x10 -4 Pa, 5.0x10 -4 Pa, 5.1x10 -4 Pa, 5.2x10 -4 Pa, 5.3x10 -4 Pa, 5.4x10 -4 Pa, 5.5x10 -4 Pa. In this way, the vacuum degree of the chamber is in a suitable range, which is conducive to ensuring the quality of the third electrode 126. Preferably, the preset vacuum degree threshold is 5.0x10 -4 Pa.

[0168] Further, when sputtering the third electrode 126 on the fourth contact layer 125, the range of the control current is 23A-27A. For example, 23A, 24A, 25A, 26A, 27A. In this way, the current is in a suitable range, which is conducive to ensuring the quality of the third electrode 126. Preferably, the current is 25A.

[0169] Further, when sputtering the third electrode 126 on the fourth contact layer 125, the range of the control deposition rate is 0.8A / s-1.2A / s. For example, 0.8A / s, 0.9A / s, 1.0A / s, 1.1A / s, 1.2A / s. In this way, the deposition rate is in a suitable range, which is conducive to ensuring the quality of the third electrode 126. Preferably, the deposition rate is 1.0A / s.

[0170] The third contact layer 123, the second perovskite light absorption layer 124, and the fourth contact layer 125 are explained as follows. For brevity, the explanations of the first contact layer 114, the first perovskite light absorption layer 115, and the second contact layer 116 are not repeated here.

[0171] Please refer to Figure 1The perovskite cell 10 includes a first lead wire 127 and a second lead wire 128. One end of the first lead wire 127 is connected to the third conductive layer 122 through the glass substrate layer 121, and one end of the second lead wire 128 is connected to the third electrode 126. The PERC cell 220 includes a third lead wire 221 and a fourth lead wire 222. One end of the third lead wire 221 is connected to the electrode of the PERC cell 220 on the side facing the perovskite cell 10, and one end of the fourth lead wire 222 is connected to the electrode of the PERC cell 220 on the side facing away from the perovskite cell 10 through the third water absorption layer 33. In this way, the electrodes of the perovskite cell 10 and the PERC cell 220 are respectively led out to form a four-terminal stacked cell. It can be understood that the first lead wire 127 can also be connected to the third conductive layer 122 from the side of the cell, and the fourth lead wire 222 can also be connected to the electrode of the PERC cell 220 on the side facing away from the perovskite cell 10 from the side of the cell.

[0172] Referring to Figure 2 The perovskite cell 10 includes a first lead wire 127 and a second lead wire 128. One end of the first lead wire 127 is connected to the third conductive layer 122 through the glass substrate layer 121, and one end of the second lead wire 128 is connected to the third electrode 126, and the other end of the second lead wire 128 is connected to the electrode of the PERC cell 220 on the side facing the perovskite cell 10. The PERC cell 220 includes a fourth lead wire 222. One end of the fourth lead wire 222 is connected to the electrode of the PERC cell 220 on the side facing away from the perovskite cell 10 through the third water absorption layer 33. In this way, the perovskite cell 10 and the PERC cell 220 are connected in series to form a four-terminal stacked cell. It can be understood that the first lead wire 127 can also be connected to the third conductive layer 122 from the side of the cell, and the fourth lead wire 222 can also be connected to the electrode of the PERC cell 220 on the side facing away from the perovskite cell 10 from the side of the cell.

[0173] Referring to Figure 2 The method for manufacturing the stacked solar cell 100 of the embodiment of the present application includes:

[0174] Step S11: manufacturing the perovskite cell 10 and the crystalline silicon cell 20 arranged in a stack, the perovskite cell 10 including a first surface 101 on the side facing away from the crystalline silicon cell 20, and the crystalline silicon cell 20 including a second surface 201 on the side facing away from the perovskite cell 10;

[0175] Step S12: depositing a water absorption layer on the first surface 101 and / or the second surface 201.

[0176] The manufacturing method of the laminated solar cell 100 in the embodiment of the present application can reduce the damage of water vapor to the perovskite cell 10, and is beneficial to improve the humidity stability of the laminated solar cell 100, because the water molecules in the air are absorbed by the water absorption layer when the water molecules contact the water absorption layer.

[0177] Specifically, in the example of Figure 3 , in step S11, the silicon substrate can be textured to obtain a light trapping structure; the textured silicon wafer is cleaned by using RCA1 and RCA2; the textured silicon wafer is cleaned again by using hydrofluoric acid; the first passivation layer 213, the first carrier selection layer 212 and the conductive composite layer 211 are sequentially deposited on one surface of the cleaned silicon wafer; the second passivation layer 215, the second carrier selection layer 216, the second conductive layer 217 and the second electrode 218 are sequentially deposited on the other surface of the cleaned silicon wafer to manufacture the HJT cell 210; the second contact layer 116, the first perovskite light absorption layer 115, the first contact layer 114, the first conductive layer 113, the anti-reflection layer 112 and the first electrode 111 are sequentially deposited on the conductive composite layer 211 to form the perovskite cell 10; and the perovskite cell 10 and the HJT cell 210 are manufactured into a laminated cell 100.

[0178] Specifically, in step S12, after the HJT cell 210 and the perovskite cell 10 are manufactured and the laminated cell 100 is formed, the first water absorption layer 31 can be deposited on the first surface 101, and the second water absorption layer 32 can be deposited on the second surface 201, as shown in Figure 5 ; or the second water absorption layer 32 can be deposited on the second surface 201 after the deposition of the second electrode 218, and the first water absorption layer 31 can be deposited on the first surface 101 after the deposition of the first electrode 111. In other words, step S11 and step S12 can be sequentially executed, or step S12 can be executed in step S11. The execution order of step S11 and step S12 is not limited herein.

[0179] Specifically, in the example of Figure 6 and Figure 1 , in step S11, the glass substrate layer 121 on which the third conductive layer 122 is deposited can be cleaned; the third contact layer 123, the second perovskite light absorption layer 124, the fourth contact layer 125 and the third electrode 126 are sequentially prepared on the cleaned third conductive layer 122 to form the perovskite cell 10; the PERC cell 220 is prepared; and the perovskite cell 10 and the PERC cell 220 are manufactured into a laminated cell 100.

[0180] It should be noted that, as mentioned above, the electrodes of the perovskite cell 10 and the PERC cell 220 can be led out respectively to form a four-terminal stacked cell. The perovskite cell 10 and the PERC cell 220 can also be connected in series to form a four-terminal stacked cell.

[0181] Specifically, in step S12, the third water absorption layer 33 can be deposited on the second surface 201 after the PERC cell 220 and the perovskite cell 10 are manufactured and the stacked cell 100 is formed; or the third water absorption layer 33 can be deposited on the second surface 201 before the perovskite cell 10 is manufactured after the PERC cell 220 is manufactured. In other words, step S11 and step S12 can be executed sequentially, or step S12 can be executed in step S11. The execution order of step S11 and step S12 is not limited herein.

[0182] Referring to Figure 2 Optionally, step S12 comprises:

[0183] Step S121: coating a raw material solution of the water absorption layer on the first surface 101 and / or the second surface 201.

[0184] Step S122: performing annealing treatment on the stacked solar cell 100 coated with the raw material solution to obtain the water absorption layer.

[0185] In this way, the deposition of the water absorption layer is realized, and the efficiency is high, and the quality of the deposited water absorption layer is good.

[0186] Optionally, in step S122, the annealing temperature ranges from 60°C to 80°C. For example, 60°C, 62°C, 65°C, 67°C, 70°C, 73°C, 75°C, 79°C, or 80°C. In this way, the annealing temperature is in a suitable range, so that the effect of annealing is good, and the quality of the generated water absorption layer is good. Preferably, the annealing temperature is 70°C. In this way, the quality of the generated water absorption layer is best.

[0187] Optionally, the raw material solution is coated on the first surface 101 and / or the second surface 201 by spraying, spin coating, or blade coating. In this way, the coating of the raw material solution is more uniform, which is conducive to improving the humidity stability of the stacked solar cell 100.

[0188] Referring to Figure 3 Optionally, step S121 comprises:

[0189] Step S1211: spraying the raw material solution on the first surface 101 and / or the second surface 201.

[0190] Step S1212: spin coating and / or blade coating the raw material solution sprayed on the first surface 101 and / or the second surface 201.

[0191] Thus, by twice coating, the coating of the raw material solution is more uniform, ensuring that the entire surface is coated and avoiding omissions. In this way, the resulting water absorption layer is completely continuous, without holes, avoiding the entry of water vapor from the holes into the interior of the battery, favoring the improvement of the humidity stability of the laminated solar cell 100.

[0192] In particular, in the example of ​ In particular, in the example of

[0193] Note that the first water absorption layer 31 covers the first electrode 111 and the anti-reflective layer 112, the first surface 101 including the top surface of the anti-reflective layer 112 and the surface of the first electrode 111 exposed from the anti-reflective layer 112. The second water absorption layer 32 covers the second electrode 218 and the second conductive layer 217, the second surface 201 including the bottom surface of the second conductive layer 217 and the surface of the second electrode 218 exposed from the second conductive layer 217.

[0194] It can be understood that, in the case where the anti-reflective layer is not provided, the first water absorption layer 31 covers the first electrode 111 and the first conductive layer 113, the first surface 101 including the top surface of the first conductive layer 113 and the surface of the first electrode 111 exposed from the first conductive layer 113.

[0195] In particular, the raw material solution can be sprayed on the non-electrode surface of the first surface 101, and then spin coating and / or blade coating can be performed to deposit the raw material solution on the surface of the first electrode 111 exposed. It can be understood that the first surface 101 can also be sprayed on the entire surface; the raw material solution can also be sprayed on the surface of the first electrode 111 exposed, and then spin coating and / or blade coating can be performed to deposit the raw material solution on the non-electrode surface of the first surface 101.

[0196] Similarly, the raw material solution can be sprayed on the non-electrode surface of the second surface 201, and then spin coating and / or blade coating can be performed to deposit the raw material solution on the surface of the second electrode 218 exposed. It can be understood that the second surface 201 can also be sprayed on the entire surface; the raw material solution can also be sprayed on the surface of the second electrode 218 exposed, and then spin coating and / or blade coating can be performed to deposit the raw material solution on the non-electrode surface of the second surface 201.

[0197] In particular, the raw material solution sprayed on the first surface 101 can be spin coated only, blade coated only, or spin coated and blade coated. The raw material solution sprayed on the second surface 201 can be spin coated only, blade coated only, or spin coated and blade coated.

[0198] In​ and ​ In the example of the third water absorption layer 33, the raw material solution can be a solution of polyoxyethylene or a derivative thereof in DMF, with a molecular weight of 2000, and the raw material solution can be deposited on the second surface 201 by spraying, spin coating or blade coating. In this way, the third water absorption layer 33 is formed.

[0199] Note that the third water absorption layer 33 covers the electrode of the PERC cell 10 on the side facing away from the perovskite cell 10 and the film layer of the PERC cell 10 on the side facing away from the perovskite cell 10, and the electrode is exposed from the film layer. The second surface 201 includes the bottom surface of the film layer and the surface of the electrode exposed from the film layer.

[0200] Further explanations and descriptions of the method of manufacturing the laminated solar cell 100 according to the present embodiment can be referred to the foregoing, and will not be repeated here to avoid redundancy.

[0201] The laminated solar cell 100 according to the present embodiment is manufactured by any one of the above methods.

[0202] The laminated solar cell 100 according to the present embodiment has a water absorption layer on the first surface 101 and / or the second surface 201, so that when the water molecules in the air contact the water absorption layer, the water molecules are absorbed by the water absorption layer, which can reduce the damage of water vapor to the perovskite cell 10 and improve the humidity stability of the laminated solar cell 100.

[0203] Further explanations and descriptions of the present embodiment can be referred to the foregoing, and will not be repeated here to avoid redundancy.

[0204] In summary, the laminated solar cell 100 and the method of manufacturing the same according to the present embodiment have a water absorption layer deposited on the outer side of the laminated solar cell 100, and the water absorption layer can absorb deionized water several thousand times its own weight. When the water molecules in the air reach the edge and surface of the laminated solar cell 100 through the encapsulation adhesive film, most of the water molecules that penetrate into the device are absorbed by the water absorption layer because the water molecules exist in the form of gas and the water absorption rate of the water absorption layer is high, thereby avoiding the erosion of water vapor to the perovskite film and improving the humidity stability of the laminated solar cell 100.

[0205] The above merely describes the preferred embodiments of the present application, but should not be used to restrict the present application, and any modifications, equivalent replacements and improvements made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A tandem solar cell, characterized in that, The tandem solar cell includes a perovskite solar cell and a crystalline silicon solar cell stacked together. The perovskite solar cell includes a first surface located on the side of the perovskite solar cell facing away from the crystalline silicon solar cell. The crystalline silicon solar cell includes a second surface located on the side of the crystalline silicon solar cell facing away from the perovskite solar cell. The tandem solar cell further includes a water-absorbing layer located on the first surface and / or the second surface. The thickness of the water-absorbing layer ranges from 0.01 mm to 1 mm. The water-absorbing layer includes one or more of the following: polyvinyl alcohol, polyoxyethylene, polyacrylate, starch-acrylonitrile graft polymer hydrolysate, starch-acrylic acid copolymer, starch-acrylamide graft polymer, cellulose graft copolymer, and cellulose derivative crosslinker. A glass cover is disposed on the side of the water-absorbing layer facing away from the solar cell, and the side of the glass cover facing the water-absorbing layer has a glass light-trapping structure.

2. The tandem solar cell according to claim 1, characterized in that, The molecular weight of the absorbent layer is one or more of low molecular weight, medium molecular weight, and high molecular weight.

3. A method for manufacturing a tandem solar cell, characterized in that, include: A crystalline silicon solar cell and a perovskite solar cell are fabricated in a stacked configuration. The perovskite solar cell includes a first surface located on the side of the perovskite solar cell away from the crystalline silicon solar cell, and the crystalline silicon solar cell includes a second surface located on the side of the crystalline silicon solar cell away from the perovskite solar cell. A water-absorbing layer is deposited on the first surface and / or the second surface; the thickness of the water-absorbing layer ranges from 0.01 mm to 1 mm; the water-absorbing layer includes one or more of the following: polyvinyl alcohol, polyoxyethylene, polyacrylate, starch-acrylonitrile graft polymer hydrolysate, starch-acrylic acid copolymer, starch-acrylamide graft polymer, cellulose graft copolymer, cellulose derivative crosslinker, etc. A glass cover is provided on the side of the absorbent layer away from the battery, and the side of the glass cover facing the absorbent layer has a light-trapping structure.

4. The method for manufacturing a tandem solar cell according to claim 3, characterized in that, Depositing a water-absorbing layer on the first surface and / or the second surface includes: A raw material solution for coating an absorbent layer onto the first surface and / or the second surface; The tandem solar cell coated with the raw material solution is annealed to obtain the water-absorbing layer.

5. The method for manufacturing a tandem solar cell according to claim 4, characterized in that, The raw material solution for coating the absorbent layer on the first surface and / or the second surface includes: The raw material solution is applied to the first surface and / or the second surface using a spraying, spin coating, or scraping process.

6. The method for manufacturing a tandem solar cell according to claim 4, characterized in that, In the step of annealing the tandem solar cell coated with the raw material solution to obtain the water-absorbing layer, the annealing temperature ranges from 60°C to 80°C.

7. A tandem solar cell, characterized in that, It is prepared by the method described in any one of claims 3-6.

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