Perovskite solar cell and preparation method thereof

Abstract

The present invention relates to a perovskite solar cell and a method for preparing the same. The perovskite solar cell comprises a stacked first solar cell unit for absorbing short-wavelength sunlight while allowing long-wavelength sunlight to pass through, a second solar cell unit for absorbing long-wavelength sunlight, and an insulating layer. The first solar cell unit comprises a plurality of first subcells connected in series or in parallel, each comprising a plurality of alternating active and inactive regions. The second solar cell unit comprises a plurality of second subcells connected in series or in parallel, each comprising a plurality of alternating active and inactive regions. A first transparent back electrode and a second transparent back electrode are disposed opposite each other, and the projections of the inactive regions of the first and second solar cell units on the insulating layer do not overlap. The perovskite solar cell of the present invention can increase power generation efficiency and photoelectric conversion efficiency.

Description

Technical Field

[0001] The present invention relates to the field of photovoltaic technology, and in particular to a perovskite solar cell and a preparation method thereof. Background Art

[0002] As a renewable energy source, solar energy is an important solution to the current energy crisis and environmental pollution. Research and development of high-efficiency, low-cost solar cells has attracted widespread attention. Perovskite solar cells are attracting widespread attention and research due to their ease of preparation, readily available and inexpensive raw materials, and their high potential for efficiency growth.

[0003] In traditional perovskite and perovskite stacking processes, the overall module current of a two-terminal series stacked battery module is limited by the lowest current of its two battery groups, resulting in low module efficiency, high process requirements, complex preparation, and high R&D and production costs. A common process for parallel four-terminal stacked battery modules involves forming a first perovskite layer upward on the same substrate, then covering it with a transparent insulating layer, and then forming a second perovskite layer on top of it, and then covering it with glass for packaging. The preparation process is complex, and the various processes may interfere with each other, affecting the first perovskite layer, thereby affecting the efficiency of the entire module and increasing the defect rate. Summary of the Invention

[0004] Based on this, it is necessary to provide a perovskite solar cell and a preparation method thereof that can improve the efficiency of the entire component in order to solve the problem of how to improve the efficiency of the component.

[0005] A perovskite solar cell, comprising a stacked first solar cell unit configured to absorb short-wavelength sunlight and transmit long-wavelength sunlight, a second solar cell unit configured to absorb long-wavelength sunlight, and an insulating layer located between the first solar cell unit and the second solar cell unit;

[0006] The first solar cell unit includes a plurality of first sub-cells connected in series or in parallel, wherein the first sub-cell includes a first substrate, a first transparent bottom electrode, a first perovskite absorption layer, and a first transparent back electrode that are stacked; the first solar cell unit includes a plurality of active areas and inactive areas that are alternately arranged;

[0007] The second solar cell unit includes a plurality of second sub-cells connected in series or in parallel, wherein the second sub-cells include a second substrate, a second transparent bottom electrode, a second perovskite absorption layer, and a second transparent back electrode that are stacked; the second solar cell unit includes a plurality of active areas and inactive areas that are alternately arranged;

[0008] The first transparent back electrode and the second transparent back electrode are arranged opposite to each other, and the projections of the ineffective area of ​​the first solar cell unit and the ineffective area of ​​the second solar cell unit on the insulating layer do not overlap.

[0009] In a perovskite solar cell employing the technical solution of the present invention, the first solar cell unit can absorb short-wavelength sunlight while allowing long-wavelength sunlight to pass through completely, while the second solar cell unit can also absorb long-wavelength sunlight, thereby increasing power generation efficiency. Furthermore, the inactive regions of the first solar cell unit and the second solar cell unit are staggered, allowing light that passes through the inactive region of either the first or second solar cell unit to still be absorbed by the active region of the other solar cell unit, thereby effectively utilizing light energy and improving photoelectric conversion efficiency. This overall arrangement can improve the efficiency of the entire assembly.

[0010] In one embodiment, the band gap of the first solar cell unit is 1.7 eV to 1.9 eV, and the band gap of the second solar cell unit is 0.9 eV to 1.2 eV.

[0011] In one embodiment, the area ratio of the active area to the inactive area of ​​the first solar cell unit is (90-99.99):(0.01-10).

[0012] In one embodiment, the area ratio of the active area to the inactive area of ​​the second solar cell unit is (90-99.99):(0.01-10).

[0013] In one embodiment, the perovskite solar cell further includes a first extraction electrode and a second extraction electrode located on both sides of edges of the first solar cell unit and the second solar cell unit.

[0014] In one embodiment, the edges of the first solar cell unit and the second solar cell unit are sealed with adhesive.

[0015] In one embodiment, one end of the first extraction electrode is located between one of the first solar cell unit and the second solar cell unit and the adhesive member, and the other end of the first extraction electrode is located between the other of the first solar cell unit and the second solar cell unit and the adhesive member;

[0016] One end of the second extraction electrode is located between one of the first solar cell unit and the second solar cell unit and the adhesive member, and the other end of the second extraction electrode is located between the other of the first solar cell unit and the second solar cell unit and the adhesive member.

[0017] In one embodiment, the projection of the adhesive member on the first substrate or the second substrate covers the projection of the first extraction electrode on the first substrate or the second substrate;

[0018] The projection of the adhesive member on the first substrate or the second substrate covers the projection of the second lead-out electrode on the first substrate or the second substrate.

[0019] In one embodiment, both the first substrate and the second substrate are glass; or

[0020] One of the first substrate and the second substrate is glass, and the other of the first substrate and the second substrate is a photovoltaic whiteboard.

[0021] A method for preparing a perovskite solar cell comprises the following steps:

[0022] A first transparent bottom electrode, a first perovskite absorption layer, and a first transparent back electrode are sequentially formed on a first substrate, and after etching, a plurality of first sub-cells connected in series or in parallel are formed to obtain a first solar cell unit that absorbs short-wavelength sunlight and allows long-wavelength sunlight to pass therethrough; the first solar cell unit includes a plurality of alternating active regions and inactive regions;

[0023] A second transparent bottom electrode, a second perovskite absorption layer, and a second transparent back electrode are sequentially formed on a second substrate, and after etching, a plurality of second sub-cells connected in series or in parallel are formed to obtain a second solar cell unit for absorbing long-wavelength sunlight; the second solar cell unit includes a plurality of alternating active areas and inactive areas; and

[0024] The first solar cell unit, the insulating layer and the second solar cell unit are compounded together, wherein the first transparent back electrode and the second transparent back electrode are arranged opposite to each other, and the projections of the ineffective area of ​​the first solar cell unit and the ineffective area of ​​the second solar cell unit on the insulating layer do not overlap, thereby obtaining a perovskite solar cell.

[0025] The preparation method of the perovskite solar cell of the above technical solution is simple to operate and has a simplified process. The same set of equipment can be used without the need for new special coating equipment. It can effectively reduce costs, increase fault tolerance, and improve production capacity, making it easier to realize the industrialization of high-efficiency perovskite solar cell modules; it can more effectively utilize light energy and improve photoelectric conversion efficiency; and the prepared perovskite solar cell has an overall beautiful appearance. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 11 is an exploded schematic diagram of a first solar cell unit, a second solar cell unit, and an insulating layer in a perovskite solar cell according to one embodiment of the present invention;

[0027] Figure 2 Schematic diagram of an adhesive member and a first extraction electrode in a perovskite solar cell according to one embodiment of the present invention;

[0028] Figure 3 Schematic diagram of a first extraction electrode and a second extraction electrode in a perovskite solar cell according to one embodiment of the present invention;

[0029] Figure 4 Schematic diagram of a first extraction electrode, a second extraction electrode, and an adhesive member in a perovskite solar cell according to one embodiment of the present invention. DETAILED DESCRIPTION

[0030] To make the above-mentioned objects, features, and advantages of the present invention more readily apparent, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. The following description sets forth numerous specific details to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art may make similar modifications without departing from the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used in this specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0032] See Figure 1 A perovskite solar cell 100 according to one embodiment of the present invention includes a first solar cell unit 110 that is stacked to absorb short-wavelength sunlight and allow long-wavelength sunlight to pass through, a second solar cell unit 120 that is stacked to absorb long-wavelength sunlight, and an insulating layer 130 located between the first solar cell unit 110 and the second solar cell unit 120.

[0033] The first solar cell unit 110 includes a plurality of first sub-cells 111 connected in series. The first sub-cell 111 includes a stacked first substrate 112, a first transparent bottom electrode 113, a first perovskite absorber layer 114, and a first transparent back electrode 115. The first solar cell unit 110 includes a plurality of alternating active regions b1 and inactive regions a1.

[0034] The second solar cell unit 120 includes a plurality of second sub-cells 121 connected in series. The second sub-cells 121 include a stacked second substrate 122, a second transparent bottom electrode 123, a second perovskite absorber layer 124, and a second transparent back electrode 125. The second solar cell unit 120 includes a plurality of alternating active regions b2 and inactive regions a2.

[0035] The first transparent back electrode 115 and the second transparent back electrode 125 are disposed opposite each other, and the projections of the inactive area a1 of the first solar cell unit 110 and the inactive area a2 of the second solar cell unit 120 on the insulating layer 130 do not overlap. In other words, the inactive area a1 of the first solar cell unit 110 and the inactive area a2 of the second solar cell unit 120 are staggered.

[0036] In the above embodiment, the number of first sub-cells 111 and second sub-cells 121 is three, and the three first sub-cells 111 are connected in series, and the three second sub-cells 121 are connected in series. However, it is understood that in the perovskite solar cell of the present invention, the first solar cell unit may also include several first sub-cells connected in parallel, or several first sub-cells connected in series and in parallel; similarly, the second solar cell unit may also include several second sub-cells connected in parallel, or several second sub-cells connected in series and in parallel. The number of first sub-cells and second sub-cells is preferably 2 to 400.

[0037] In the above embodiment, the wavelength of the short-wavelength sunlight is 300 nm to 800 nm, and the wavelength of the long-wavelength sunlight is 500 nm to 1200 nm.

[0038] In the above embodiment, the first perovskite absorption layer 114 and the second perovskite absorption layer 124 each include a stacked electron transport layer, a perovskite photosensitive layer and a hole transport layer. Of course, they may also include a passivation diffusion layer located between the electron transport layer and the perovskite photosensitive layer, or include other functional layers such as a buffer layer.

[0039] The perovskite material in the perovskite photosensitive layer has an ABX3 structure, and the crystal structure of the perovskite material can be a cubic lattice, a prism structure (trigonal system), or an orthorhombic structure. Preferably, A in the ABX3 structure represents CH3NH3 + (MA), NH2CH=NH2 + (FA), Cs, or Rb; B represents one or more of Pb or Sn; X represents a halogen or pseudo-halogen; the halogen is selected from Cl, Br, or I; the pseudo-halogen is selected from CN, thiocyanate (SCN), oxycyanate (OCN), or selenium cyanide (SeCN). More preferably, the general formula of the perovskite material is MA xFA 1-x PbI 3-a Br a 、MA x FA 1-x PbI 3-b Cl b , or MA x FA 1- x PbBr 3-c Cl c ; wherein x is 0 to 1, and a, b, and c are all 0 to 3. The perovskite photosensitive layer 140 may also be doped with an alkali metal salt.

[0040] In the above embodiment, the inactive regions a1 and a2 are also called "photovoltaic dead zones" and are areas that cannot function as solar cells. They can be etched out by laser or other means to achieve series and parallel connections. The active regions b1 and b2 are areas that actually generate electricity.

[0041] In the above embodiment, the thickness of the first substrate 112 and the second substrate 122 is 0.7 mm to 5 mm, and the area is 0.02 m 2 ~4m 2 The first transparent bottom electrode 113 and the second transparent bottom electrode 123 include, but are not limited to, ITO, FTO, IWO, AZO, IGO, and IZO, and have a thickness of 50 nm to 2000 nm. The first perovskite absorber layer 114 and the second perovskite absorber layer 124 have a thickness of 100 nm to 5000 nm. The first transparent back electrode 115 and the second transparent back electrode 125 include, but are not limited to, ITO, FTO, IWO, AZO, IGO, and IZO, and have a thickness of 50 nm to 2000 nm.

[0042] In the above embodiment, the insulating layer 130 may be an adhesive, or a composite layer of an adhesive and a transparent substrate, and the transparent substrate may be, for example, glass, etc. The adhesive includes but is not limited to EVA or POE.

[0043] Using the perovskite solar cell of the above embodiment, the first solar cell unit can absorb short-wavelength sunlight while allowing long-wavelength sunlight to pass through, while the second solar cell unit can also absorb long-wavelength sunlight, which helps increase power generation efficiency. Furthermore, the inactive regions of the first solar cell unit and the second solar cell unit are staggered, so that after the incident light passes through the inactive region of the first or second solar cell unit, it can still be absorbed by the active region of the other solar cell unit, thereby effectively utilizing light energy and improving photoelectric conversion efficiency. This overall arrangement can improve the efficiency of the entire assembly.

[0044] Based on the aforementioned embodiment, the band gap of the first solar cell 110 is 1.7 eV to 1.9 eV, and the band gap of the second solar cell 120 is 0.9 eV to 1.2 eV. In this case, the band gaps of the first solar cell 110 and the second solar cell 120 complement each other, resulting in a high-efficiency all-perovskite tandem solar cell with lower cost, more stable process, higher efficiency, and greater suitability for industrial production.

[0045] Based on the aforementioned embodiment, the area ratio of the active area b1 to the inactive area a1 of the first solar cell unit 110 is (90-99.99):(0.01-10). This maximizes the active area b1 of the first solar cell unit 110 while enabling the series or parallel connection of adjacent first sub-cells 111 within the first solar cell unit 110, thereby improving the efficiency of the perovskite solar cell module.

[0046] Based on the aforementioned embodiment, the area ratio of the active area b2 to the inactive area a2 of the second solar cell unit 120 is (90-99.99):(0.01-10). This maximizes the active area b2 of the second solar cell unit 120 while enabling the series or parallel connection of adjacent second sub-cells 121 within the second solar cell unit 120, thereby improving the efficiency of the perovskite solar cell module.

[0047] Based on the aforementioned embodiment, the perovskite solar cell 100 further includes a first extraction electrode 140 and a second extraction electrode 150 located on either side of the edges of the first solar cell unit 110 and the second solar cell unit 120. In other words, the first solar cell unit 110 and the second solar cell unit 120 are internally connected in parallel, and the first extraction electrode 140 and the second extraction electrode 150 are jointly extracted using a pseudo-two-terminal method, which reduces costs, simplifies operation, and improves aesthetics.

[0048] In this embodiment, the first extraction electrode 140 is located between the first transparent bottom electrode 113 and the second transparent bottom electrode 123. Figure 2 As shown, the two ends of the first extraction electrode 140 are electrically connected to the first transparent bottom electrode 113 and the second transparent bottom electrode 123, which are individually exposed at the edge. The second extraction electrode 150 is located between the first transparent back electrode 115 and the second transparent back electrode 125, and the two ends of the second extraction electrode 150 are electrically connected to the first transparent back electrode 115 and the second transparent back electrode 125, which are individually exposed at the edge.

[0049] It should be noted that Figure 1The first extraction electrode 140 and the second extraction electrode 150 are merely illustrative of their positions in the first solar cell unit 110 and the second solar cell unit 120. The first extraction electrode 140 on the first transparent bottom electrode 113 and the first extraction electrode 140 on the second transparent bottom electrode 123 are the same extraction electrode, and the second extraction electrode 150 on the first transparent back electrode 115 and the second extraction electrode 150 on the second transparent back electrode 125 are the same extraction electrode.

[0050] Please also see Figure 3 The first and second extraction electrodes 140 and 150 extend to the outside of the perovskite solar cell 100 and bend toward the center of the module to connect to an external junction box. It is understood that the location of the junction box is not fixed and can be anywhere in the module. Therefore, the locations where the first and second extraction electrodes 140 and 150 extend are also not fixed.

[0051] On the basis of the above-mentioned embodiment, the edges of the first solar cell unit 110 and the second solar cell unit 120 are sealed by using adhesive 160, such as Figure 2 and Figure 4 The adhesive member 160 may be an opaque edge-sealing tape, for example, a butyl tape, etc. The adhesive member 160 may have a width of 1 mm to 30 mm and a thickness of 0.1 mm to 3 mm.

[0052] Based on the above embodiment, one end of the first extraction electrode 140 is located between one of the first solar cell 110 and the second solar cell 120 and the adhesive member 160, and the other end of the first extraction electrode 140 is located between the other of the first solar cell 110 and the second solar cell 120 and the adhesive member 160.

[0053] One end of the second extraction electrode 150 is located between one of the first solar cell 110 and the second solar cell 120 and the adhesive 160, and the other end of the second extraction electrode 150 is located between the other of the first solar cell 110 and the second solar cell 120 and the adhesive 160. This not only achieves edge sealing and serves to block water and oxygen, but also enables electrical connection between the first solar cell 110 and the second solar cell 120, which helps to reduce the width of the frame, increase the usable area of ​​the perovskite cell, and improve the effective use area of ​​the module.

[0054] Based on the aforementioned embodiment, the projection of the adhesive member 160 on the first substrate 112 or the second substrate 122 covers the projection of the first extraction electrode 140 on the first substrate 112 or the second substrate 122; and the projection of the adhesive member 160 on the first substrate 112 or the second substrate 122 covers the projection of the second extraction electrode 150 on the first substrate 112 or the second substrate 122. In this way, the adhesive member 160 can protect the first extraction electrode 140 and the second extraction electrode 150 and provide a completely sealed edge seal.

[0055] Based on the above embodiment, the first substrate 112 and the second substrate 122 are both made of glass; or

[0056] One of the first substrate 112 and the second substrate 122 is glass, and the other is a photovoltaic whiteboard. When the other is a photovoltaic whiteboard, the second solar cell 120, with the photovoltaic whiteboard serving as the substrate, acts as the lower cell. This increases the whiteboard's reflectivity of sunlight, improving photoelectric conversion efficiency. This allows for applications where transparency is not a requirement (e.g., power stations, rooftops), while also eliminating a piece of glass, reducing cost and module weight.

[0057] Of course, the first substrate 112 and the second substrate 122 may also be other flexible substrates such as PET (polyethylene terephthalate), PEN (polyethylene naphthalate), and PI (polyethylene naphthalate).

[0058] A method for preparing a perovskite solar cell according to one embodiment includes the following steps:

[0059] S10. A first transparent bottom electrode, a first perovskite absorption layer, and a first transparent back electrode are sequentially formed on a first substrate. After etching, a plurality of first sub-cells connected in series or in parallel are formed to obtain a first solar cell unit that absorbs short-wavelength sunlight and allows long-wavelength sunlight to pass therethrough; the first solar cell unit includes a plurality of alternatingly arranged effective areas and ineffective areas.

[0060] Please also see Figure 1 In the first solar cell unit 110 , the first transparent bottom electrode 113 and the first transparent back electrode 115 located at the edge have separate exposed portions.

[0061] S20. Form a second transparent bottom electrode, a second perovskite absorption layer, and a second transparent back electrode in sequence on the second substrate. After etching, a plurality of second sub-cells connected in series or in parallel are formed to obtain a second solar cell unit for absorbing long-wavelength sunlight; the second solar cell unit includes a plurality of alternatingly arranged active areas and inactive areas.

[0062] Please also see Figure 1 In the second solar cell unit 120 , the second transparent bottom electrode 123 and the second transparent back electrode 125 located at the edge have separate exposed portions.

[0063] S30. Compounding the first solar cell unit, the insulating layer, and the second solar cell unit, wherein the first transparent back electrode and the second transparent back electrode are arranged opposite to each other, and the projections of the ineffective area of ​​the first solar cell unit and the ineffective area of ​​the second solar cell unit on the insulating layer do not overlap, thereby obtaining a perovskite solar cell.

[0064] Further, please see Figure 2 The perovskite solar cell 100 further includes a first extraction electrode 140 and a second extraction electrode 150 located on both sides of the edges of the first solar cell unit 110 and the second solar cell unit 120 .

[0065] After the first solar cell unit 110 and the second solar cell unit 120 are respectively manufactured through step S10 and step S20, the edge of the first solar cell unit 110 or the second solar cell unit 120 is covered with Figure 4 A certain length of adhesive piece (such as opaque edge-sealing tape) is shown, and then the first lead-out electrode 140 and the second lead-out electrode 150 are adhered to the above-mentioned adhesive piece, and then another part of the adhesive piece is adhered to the other side of the first lead-out electrode 140 and the second lead-out electrode 150, and then the second solar cell unit 120 or the first solar cell unit 110 is aligned and pressed with the insulating layer.

[0066] It should be noted that in the method for preparing a perovskite solar cell of the above embodiment, the order of step S10 and step S20 is not limited. Step S10 can be performed first and then step S20; step S20 can also be performed first and then step S10; of course, step S10 and step S20 can also be performed simultaneously.

[0067] The preparation method of the perovskite tandem solar cell of the above technical solution is simple to operate and has a simplified process. The same set of equipment can be used without the need for new special coating equipment. It can effectively reduce costs, increase fault tolerance, and improve production capacity, making it easier to realize the industrialization of high-efficiency perovskite tandem solar cell modules; more effectively utilize light energy and improve photoelectric conversion efficiency; the prepared perovskite solar cell has an overall beautiful appearance.

[0068] With reference to the above implementation content, in order to make the technical solution of this application more specific, clear and easy to understand, the technical solution of this application is now given as an example. However, it should be noted that the content to be protected by this application is not limited to the following embodiments.

[0069] Example 1

[0070] On the first substrate, an ITO transparent bottom electrode, [CH(NH2)2] 0.8 Cs 0.2 PbI 1.5 Br 1.5 The perovskite absorber layer and the ITO transparent back electrode are etched to form 85 first subcells connected in series, resulting in a first solar cell unit. The first solar cell unit includes several alternating active and inactive regions. The band gap in the first solar cell unit is 1.8 eV, and the area ratio of the active to inactive regions is 98.1:1.9.

[0071] On the second substrate, an ITO transparent bottom electrode, a CH3NH3Pb 0.5 Sn 0.5 The I3 perovskite absorber layer and the ITO transparent back electrode are then etched to form 120 second subcells connected in series, resulting in a second solar cell unit. This second solar cell unit comprises several alternating active and inactive regions. The band gap in this second solar cell unit is 1.2 eV, and the active to inactive region area ratio is 97.2:2.8.

[0072] The edge of the first solar cell is covered as Figure 4 A certain length of partially opaque edge-sealing tape is then attached to the partially adhesive member, and then the first and second lead electrodes are attached to the other sides of the first and second lead electrodes. Another portion of the opaque edge-sealing tape is then attached to the other sides of the first and second lead electrodes. The second solar cell unit or the first solar cell unit is then aligned and pressed against the insulating layer to obtain the perovskite solar cell of Example 1. The ITO transparent back electrode of the first solar cell unit and the ITO transparent back electrode of the second solar cell unit are arranged opposite each other, and the projections of the inactive areas of the first solar cell unit and the inactive areas of the second solar cell unit on the insulating layer do not overlap.

[0073] The total area of ​​the perovskite solar cell of Example 1 is 3000 cm 2 The effective area of ​​the perovskite cell is 2679 cm 2 .

[0074] The module efficiency of the perovskite solar cell of Example 1 was tested to be 16.3%.

[0075] Example 2

[0076] On the first substrate, an ITO transparent bottom electrode, [CH(NH2)2] 0.8 Cs 0.2 PbI1.5 Br 1.5 The perovskite absorber layer and the ITO transparent back electrode were etched to form five parallel cell groups. Each cell group contained 17 cells connected in series, for a total of 85 first sub-cells connected in series and parallel, forming a first solar cell unit. The first solar cell unit consisted of several alternating active and inactive regions. The band gap in the first solar cell unit was 1.8 eV, and the area ratio of the active to inactive regions was 98.2:1.8.

[0077] On the second substrate, an ITO transparent bottom electrode, a CH3NH3Pb 0.5 Sn 0.5 The I3 perovskite absorber layer and the ITO transparent back electrode were etched to form six parallel cell groups. Each cell group contained 20 cells connected in series, for a total of 120 second sub-cells connected in series and parallel, forming a second solar cell unit. The second solar cell unit consisted of several alternating active and inactive regions. The band gap in the second solar cell unit was 1.2 eV, and the area ratio of the active to inactive regions was 97.3:2.7.

[0078] The edge of the first solar cell is covered as Figure 4 A certain length of partial opaque edge-sealing tape is shown, and then the first and second lead electrodes are attached to the aforementioned partial adhesive member. Then, another portion of opaque edge-sealing tape is attached to the other sides of the first and second lead electrodes. Then, the second solar cell unit or the first solar cell unit is aligned and pressed with the insulating layer to obtain the perovskite solar cell of Example 2. The ITO transparent back electrode of the first solar cell unit and the ITO transparent back electrode of the second solar cell unit are arranged opposite each other, and the projections of the inactive areas of the first solar cell unit and the inactive areas of the second solar cell unit on the insulating layer do not overlap.

[0079] The total area of ​​the perovskite solar cell of Example 2 is 3000 cm 2 The effective area of ​​the perovskite cell is 2679 cm 2 .

[0080] The module efficiency of the perovskite solar cell of Example 2 was tested to be 16%.

[0081] Comparative Example 1

[0082] This comparative example, a comparison to Example 1, provides a perovskite solar cell and a method for fabricating the same. The method differs from that in Example 1 only in that a first solar cell unit is fabricated on a single substrate, with the first solar cell unit positioned upwards. This unit is then covered with a transparent insulating layer, and then a first solar cell unit is fabricated thereon. The perovskite solar cell of Comparative Example 1 exhibited a module efficiency of 14%.

[0083] By comparison, it can be seen that the module efficiency of the perovskite solar cell of Example 1 is 2.3% higher than that of the perovskite solar cell of Comparative Example 1, which shows that the preparation method of the perovskite solar cell of the present invention can improve the module efficiency.

[0084] Comparative Example 2

[0085] This comparative example, a comparison to Example 1, provides a perovskite solar cell and a method for preparing the same. The only difference from the perovskite solar cell in Example 1 is that the projections of the inactive regions of the first and second solar cell units on the insulating layer overlap. The perovskite solar cell of Comparative Example 2 achieved a module efficiency of 15.5%.

[0086] By comparison, it can be seen that the module efficiency of the perovskite solar cell of Example 1 is 0.8% higher than that of the perovskite solar cell of Comparative Example 2, which shows that the perovskite solar cell of the present invention can improve the module efficiency.

[0087] Comparative Example 3

[0088] This comparative example is a comparative example of Example 1 and provides a method for preparing a perovskite solar cell module. The only difference from the perovskite solar cell module of Example 1 is that the projections of the first and second lead electrodes do not overlap with the adhesive, and the adhesive is disposed on the periphery of the first and second lead electrodes. The total area of ​​the perovskite solar cell module of Comparative Example 3 is 3000 cm 2 The effective area of ​​the perovskite cell is 2538 cm 2 .

[0089] By comparison, it can be seen that the effective area of ​​the perovskite solar cell module of Example 1 is increased by 141 cm 2 This indicates that the perovskite solar cell module of the present invention can increase the effective utilization area per unit of illumination.

[0090] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0091] The above-described embodiments merely illustrate several implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A perovskite solar cell, comprising a stacked first solar cell unit configured to absorb short-wavelength sunlight and transmit long-wavelength sunlight, a second solar cell unit configured to absorb long-wavelength sunlight, and an insulating layer located between the first solar cell unit and the second solar cell unit; Its characteristics are: The first solar cell unit includes a plurality of first sub-cells connected in series or in parallel, wherein the first sub-cell includes a first substrate, a first transparent bottom electrode, a first perovskite absorption layer, and a first transparent back electrode that are stacked; the first solar cell unit includes a plurality of active areas and inactive areas that are alternately arranged; The second solar cell unit includes a plurality of second sub-cells connected in series or in parallel, wherein the second sub-cells include a second substrate, a second transparent bottom electrode, a second perovskite absorption layer, and a second transparent back electrode that are stacked; the second solar cell unit includes a plurality of active areas and inactive areas that are alternately arranged; The invalid area is a photovoltaic dead zone, the effective area is an actual effective power generation area, the first transparent back electrode and the second transparent back electrode are arranged opposite to each other, the invalid area of ​​the first solar cell unit and the invalid area of ​​the second solar cell unit are respectively projected on the insulating layer without overlapping, and after the irradiated light passes through the invalid area of ​​the first solar cell unit or the second solar cell unit, it can still be absorbed by the effective area of ​​the other solar cell unit.

2. The perovskite solar cell according to claim 1, characterized in that The band gap of the first solar cell unit is 1.7 eV to 1.9 eV, and the band gap of the second solar cell unit is 0.9 eV to 1.2 eV.

3. The perovskite solar cell according to claim 1, wherein The area ratio of the active area to the inactive area of ​​the first solar cell unit is (90-99.99):(0.01-10).

4. The perovskite solar cell according to claim 1, wherein The area ratio of the active area to the inactive area of ​​the second solar cell unit is (90-99.99):(0.01-10).

5. The perovskite solar cell according to claim 1, characterized in that The perovskite solar cell further includes a first lead-out electrode and a second lead-out electrode located on both sides of edges of the first solar cell unit and the second solar cell unit.

6. The perovskite solar cell according to claim 5, characterized in that The edges of the first solar cell unit and the second solar cell unit are sealed by using adhesives.

7. The perovskite solar cell according to claim 6, characterized in that One end of the first extraction electrode is located between one of the first solar cell unit and the second solar cell unit and the adhesive member, and the other end of the first extraction electrode is located between the other of the first solar cell unit and the second solar cell unit and the adhesive member; One end of the second extraction electrode is located between one of the first solar cell unit and the second solar cell unit and the adhesive member, and the other end of the second extraction electrode is located between the other of the first solar cell unit and the second solar cell unit and the adhesive member.

8. The perovskite solar cell according to claim 7, characterized in that The projection of the adhesive member on the first substrate or the second substrate covers the projection of the first extraction electrode on the first substrate or the second substrate; The projection of the adhesive member on the first substrate or the second substrate covers the projection of the second lead-out electrode on the first substrate or the second substrate.

9. The perovskite solar cell according to claim 1, wherein The first substrate and the second substrate are both made of glass; or one of the first substrate and the second substrate is made of glass, and the other of the first substrate and the second substrate is a photovoltaic whiteboard.

10. The method for preparing a perovskite solar cell according to any one of claims 1 to 9, characterized in that: The steps include: A first transparent bottom electrode, a first perovskite absorption layer, and a first transparent back electrode are sequentially formed on a first substrate, and after etching, a plurality of first sub-cells connected in series or in parallel are formed to obtain a first solar cell unit that absorbs short-wavelength sunlight and allows long-wavelength sunlight to pass therethrough; the first solar cell unit includes a plurality of alternating active regions and inactive regions; A second transparent bottom electrode, a second perovskite absorption layer, and a second transparent back electrode are sequentially formed on a second substrate, and after etching, a plurality of second sub-cells connected in series or in parallel are formed to obtain a second solar cell unit for absorbing long-wavelength sunlight; the second solar cell unit includes a plurality of alternating active areas and inactive areas; and The first solar cell unit, the insulating layer and the second solar cell unit are compounded together, wherein the first transparent back electrode and the second transparent back electrode are arranged opposite to each other, and the projections of the ineffective area of ​​the first solar cell unit and the ineffective area of ​​the second solar cell unit on the insulating layer do not overlap, thereby obtaining a perovskite solar cell.

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