Laminated cell, photovoltaic module and processing method of laminated cell

Abstract

The embodiment of the invention provides a laminated cell, a photovoltaic module and a processing method of the laminated cell, the laminated cell comprises a bottom cell, a composite layer and a top cell, and the composite layer is located between the top cell and the bottom cell and is connected with the top cell and the bottom cell. And a plurality of first convex parts and / or a plurality of first concave parts are arranged on one side, facing the top cell, of the composite layer. The first convex part is convex towards the direction close to the top battery, and the first concave part is concave towards the direction far away from the top battery. Through the design, the contact stability between the top cell and the composite layer can be improved, so that the performance and the efficiency of the laminated cell can be improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of solar energy, and in particular to a laminated cell, a photovoltaic module, and a method for processing the laminated cell. Background Art

[0002] With the development of technology, the application of photovoltaic modules is becoming more and more extensive. Photovoltaic modules include solar cells. Tandem cells have a high photoelectric conversion rate and are considered to be low-cost, high-efficiency cells with great potential. Therefore, it is necessary to further improve the performance and efficiency of tandem cells. Summary of the Invention

[0003] The embodiments of the present application provide a laminated cell, a photovoltaic module, and a method for processing the laminated cell, for improving the performance and efficiency of the laminated cell.

[0004] An embodiment of the present application provides a stacked battery, comprising a bottom battery, a composite layer, and a top battery, wherein the composite layer is located between the bottom battery and the top battery; Wherein, a plurality of first protrusions and / or a plurality of first depressions are provided on a side of the composite layer facing the top cell.

[0005] In a possible embodiment, the bottom battery has a velvet layer on a side facing the composite layer, and along the thickness direction of the stacked battery, the composite layer is provided with a plurality of the first recessed portions, and / or the composite layer is provided with a plurality of the first protruding portions.

[0006] In a possible implementation manner, the width a of each of the first recessed portions gradually decreases in a direction approaching the bottom cell, and / or; The depth of the first recessed portion gradually decreases in a direction approaching the bottom cell.

[0007] In a possible implementation manner, the width of the first recessed portion is 10 nm to 100 nm, and the depth of the first recessed portion is 10 nm to 50 nm.

[0008] In a possible implementation manner, the first recessed portion is inclined toward the bottom battery; The inclination angle of each first recessed portion gradually decreases in a direction away from the bottom cell, and / or the inclination angle of the first recessed portion relative to the width direction or the length direction of the laminated cell is 20° to 70°.

[0009] In a possible implementation manner, the protrusion size of each of the first protrusions gradually decreases in a direction approaching the bottom cell, and / or; The first protrusions are inclined in a direction away from the bottom cell, and the inclination angle of each of the first protrusions gradually increases along the direction away from the bottom cell.

[0010] In a possible implementation manner, the size of the first protrusion is 10 nm to 100 nm, and / or the inclination angle of the first protrusion relative to the width direction or the length direction of the laminated battery is 20° to 70°.

[0011] In a possible implementation, the composite layer includes a first body layer and a first substrate layer, the first substrate layer is located on a side of the first body layer away from the bottom cell, and the first protrusion and / or the first depression are provided on the first substrate layer.

[0012] In one possible implementation, the composite layer is a first transparent conductive layer, the top cell has a hole transport layer on a side facing the composite layer, and the roughness of the composite layer facing the hole transport layer is 10 nm to 100 nm.

[0013] A second aspect of the present application provides a photovoltaic module, which includes the laminated cell described in any one of the above items.

[0014] The present application also provides a method for processing a laminate battery, which is used to process any of the laminate batteries described above. The method for processing the laminate battery comprises: preparing a composite layer on the bottom cell; Processing the composite layer to form a first protrusion and / or a first depression on a side of the composite layer away from the bottom cell; preparing a hole transport layer on a side of the composite layer away from the bottom cell; preparing a perovskite layer on a side of the hole transport layer away from the composite layer; preparing an electron transport layer on a side of the perovskite layer away from the hole transport layer; preparing a second transparent conductive layer on a side of the electron transport layer away from the perovskite layer; preparing an electrode on a side of the second transparent conductive layer away from the perovskite layer; Prepare an anti-reflection layer.

[0015] In a possible implementation, the step of processing the composite layer to form a first protrusion and / or a first depression on a side of the composite layer away from the bottom cell includes: The first protrusion and / or the first depression are formed on a side of the composite layer away from the bottom cell by at least one of laser etching, photolithography, solution method, magnetron sputtering, spraying, and wet chemical alkaline polishing.

[0016] In a possible implementation, the step of processing the composite layer to form a first protrusion and / or a first depression on a side of the composite layer away from the bottom cell includes: Using a laser with a power of 5W to 80W, a laser frequency of 500KHZ to 3000KHZ, and a moving speed of 3000mm / s to 30000mm / s to etch the side of the composite layer away from the bottom cell, with the etching depth not exceeding 100nm, or; Disposing a thin resist layer on a portion of the composite layer away from the bottom cell, etching the portion not covered by the thin resist layer, and then removing the thin resist layer, or; Immersing or fumigating the bottom cell having the composite layer in a solvent containing a conductive material, or spin-coating the solvent containing a conductive material on a side of the composite layer away from the bottom cell, followed by drying; or Sputtering a conductive material with a thickness of 1 nm to 10 nm on a side of the composite layer away from the bottom cell at a power of 0.2 kW to 2 kW and a carrier moving speed of 2 mm / s to 20 mm / s, or; spraying a conductive material having a particle size of 10 nm to 100 nm onto the surface of the composite layer with a spray gun at a pressure of 2 Bar to 10 Bar on a heating platform for 1 second to 10 seconds and evaporating the conductive material, or; 2% to 10% of an etching additive is added to a 5% to 50% alkaline solution, and the composite layer is etched in a tank immersion manner.

[0017] The embodiments of the present application provide a laminated cell, a photovoltaic module, and a method for processing a laminated cell. The laminated cell includes a bottom cell 1, a composite layer, and a top cell. The composite layer is located between the top and bottom cells and is connected to the top and bottom cells. A plurality of first protrusions and / or a plurality of first depressions are provided on the side of the composite layer facing the top cell. The first protrusions protrude toward the top cell, and the first depressions are recessed away from the top cell. This design improves the stability of the contact between the top cell and the composite layer, thereby improving the performance and efficiency of the laminated cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A partial schematic diagram of a stacked battery provided in an embodiment of the present application; Figure 2 A schematic diagram of another embodiment of the stacked battery provided in an embodiment of the present application; Figure 3 A schematic diagram of another embodiment of the stacked battery provided in the embodiments of the present application; Figure 4A schematic diagram of another embodiment of the stacked battery provided in the embodiments of the present application; Figure 5 A schematic diagram of another embodiment of the stacked battery provided in the embodiments of the present application; Figure 6 A schematic diagram of another embodiment of the stacked battery provided in the embodiments of the present application; Figure 7 A schematic diagram of yet another embodiment of the stacked battery provided in the embodiments of the present application; Figure 8 A schematic diagram of another embodiment of the stacked battery provided in the embodiments of the present application; Figure 9 A schematic diagram of the bottom cell and composite layer provided in an embodiment of the present application; Figure 10 A schematic diagram of the composite layer after processing provided in an embodiment of the present application; Figure 11 This is a schematic diagram of the stacked battery provided in an embodiment of the present application after preparing the hole transport layer; Figure 12 A schematic diagram of a tandem battery provided in an embodiment of the present application after preparing a perovskite layer; Figure 13 This is a schematic diagram of the stacked battery provided in an embodiment of the present application after the electron transport layer is prepared; Figure 14 This is a schematic diagram of the laminated battery provided in an embodiment of the present application after the second transparent conductive layer is prepared; Figure 15 This is a schematic diagram of the laminated battery provided in an embodiment of the present application after electrode preparation; Figure 16 This is a schematic diagram of the stacked battery provided in an embodiment of the present application after the anti-reflection layer is prepared.

[0019] Reference numerals 1- bottom battery; 11-main layer; 12-Suede layer 121- second raised portion; 122- second recessed portion; 2-composite layer; 21- first protrusion; 22-first recessed portion; 23-first body layer; 24-first substrate layer; 3-hole transport layer; 4-Perovskite layer; 5-electron transport layer; 6- second transparent conductive layer; 7-anti-reflection layer; 8-Electrode. DETAILED DESCRIPTION

[0020] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0021] It should be clear that the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0022] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a", "an", "the" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

[0023] It should be understood that the term "and / or" as used herein simply describes a relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A alone, A and B together, or B alone. Furthermore, the character " / " in this document generally indicates an "or" relationship between the associated objects.

[0024] like Figure 1 As shown, an embodiment of the present application provides a stacked battery, which includes a bottom battery 1, a composite layer 2 and a top battery. The composite layer 2 is located between the top battery and the bottom battery 1 and is connected to the top battery and the bottom battery 1. The composite layer 2 can connect the top battery and the bottom battery 1 in series in the circuit, so that the current can be smoothly transmitted between the two sub-batteries, thereby realizing the overall power output of the stacked battery. The top battery can be a perovskite battery, the bottom battery 1 can be a crystalline silicon battery, and the bottom battery 1 can be a back contact battery, a TOPCon battery, etc. Figure 2 and Figure 3 As shown, the side of the composite layer 2 facing the top cell is provided with a plurality of first protrusions 21 and / or a plurality of first depressions 22. The first protrusions 21 protrude toward the direction close to the top cell, and the first depressions 22 are depressed toward the direction away from the top cell.

[0025] By providing a first raised portion 21 and a first recessed portion 22 on the side of the composite layer 2 facing the top cell, the contact area between the composite layer 2 and the top cell can be increased. Increasing the contact area between the composite layer 2 and the top cell can help reduce contact resistance, improve the fill factor (FF) of the tandem cell, and thereby enhance photoelectric conversion efficiency. The provision of the first raised portion 21 and / or the first recessed portion 22 increases the surface roughness of the composite layer 2, thereby increasing the number of contact points between the composite layer 2 and the top cell. This facilitates stable contact between the composite layer 2 and the top cell, thereby increasing the wettability of the perovskite and improving the efficiency and stability of the tandem cell, more effectively meeting actual usage requirements.

[0026] like Figure 2 As shown, in a possible embodiment, the bottom cell 1 has a velvet layer 12 on the side facing the composite layer 2 , and the composite layer 2 is provided with a plurality of first recessed portions 22 and / or a plurality of first raised portions 21 along the thickness direction of the laminated cell.

[0027] Providing a velvet layer 12 on the bottom cell 1 increases the surface area of ​​the bottom cell 1, thereby improving the contact stability between the bottom cell 1 and the composite layer 2. This also facilitates charge transfer. The larger contact area between the composite layer 2 and the bottom cell 1 improves the transfer of carriers from the top cell to the bottom cell 1. Furthermore, the velvet layer 12 reflects light, increasing the light transmission path and thereby improving the light absorption efficiency of the bottom cell 1.

[0028] The bottom battery 1 includes a main layer 11 and a velvet layer 12, and the velvet layer 12 is located on the side of the main layer 11 facing the top battery. The velvet layer 12 may include a plurality of protrusions, and the structure of the protrusions may be a pyramid structure. The composite layer 2 has a conformal property, so the structure of the surface of the composite layer 2 away from the bottom battery 1 is similar to the surface structure of the bottom battery 1 facing the composite layer 2, so the surface of the composite layer 2 also has a velvet structure that is approximately pyramid-shaped. The first protrusion 21 and the first depression 22 are located on the pyramid-shaped surface of the composite layer 2. The side of the composite layer 2 facing the top battery has a velvet structure and a first protrusion 21 and / or a first depression 22 at the same time. Along the thickness direction, specifically along the direction from the top of the pyramid velvet to the bottom of the pyramid, a plurality of first protrusions 21 and / or first depressions 22 are provided.

[0029] Such a design can be beneficial to utilizing the conformal properties of the composite layer 2 and further improving the roughness of the composite layer 2 facing the top battery side, thereby helping to improve the efficiency of the stacked battery, and further improving the performance of the stacked battery, which is more in line with actual usage needs.

[0030] like Figure 4As shown, in one possible embodiment, the width a of each first recessed portion 22 gradually decreases in a direction approaching the bottom cell 1, and / or the depth of the first recessed portion 22 gradually decreases in a direction approaching the bottom cell 1. The direction approaching the bottom cell 1 can be approximated as the direction from the top of the pyramid structure of the suede layer 12 to the bottom of the pyramid.

[0031] Because the bottom cell 1 has a velvet layer 12, due to the conformal properties of the composite layer 2, a velvet structure is also formed on the side of the composite layer 2 facing the top cell, that is, the side of the composite layer 2 facing the top cell has a pyramid structure. When depositing the top cell, due to the pyramid structure on the surface of the composite layer 2, less solute is deposited at the tip, and the solute flows along the surface of the pyramid structure toward the bottom cell 1, resulting in less solute at the tip and a thin thickness, while more solute is deposited between the pyramid structures and a thicker thickness. The top cell structure deposited on the surface of the composite layer 2 has an uneven thickness, such as the hole transport layer 3 (HTL). Preparing the perovskite layer 4 on the hole transport layer 3 with an uneven thickness will result in reduced wettability of the perovskite, uneven charge transfer, and affect the fill factor of the stacked cell. In severe cases, leakage will occur.

[0032] The solution provided in the embodiment of the present application can increase the surface area of ​​the composite layer 2 facing the top cell side and improve the surface roughness of the composite layer 2 by providing a first recessed portion 22 on the surface of the composite layer 2. This design can reduce the possibility of solutes flowing toward the bottom cell 1 when depositing the structure of the top cell. The width and / or depth of the first recessed portion 22 near the tip of the pyramid structure of the composite layer 2 is larger, so it can accommodate more solutes. The width and / or depth of the first recessed portion 22 near the bottom of the pyramid structure of the composite layer 2 is smaller, so it can accommodate relatively less solutes. This design can facilitate the deposition of solutes at the top of the pyramid structure, thereby reducing the possibility of solutes flowing to the bottom, making the structure of the deposited top cell more uniform, thereby improving the wettability of the top cell, making the charge transfer more uniform, reducing the impact of uneven thickness of the top cell on the fill factor, and thus improving the efficiency and quality of the stacked battery.

[0033] In one possible embodiment, the width of the first recessed portion 22 is 10 nm to 100 nm. The depth of the first recessed portion 22 is 10 nm to 50 nm. The width of the first recessed portion 22 can be 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, etc. The depth of the first recessed portion 22 can be 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, etc.

[0034] The larger the width and the deeper the first recess 22, the more solutes it can accommodate. At the same time, the surface area of ​​the composite layer 2 facing the top battery is also larger, so the contact between the composite layer 2 and the top battery is more stable, which is beneficial to charge transfer. At the same time, when the width and depth of the first recess 22 are larger, the internal space of the first recess 22 is larger, and the more solutes it can accommodate. Therefore, by increasing the width and depth of the first recess 22 away from the bottom battery 1, the corresponding position can accommodate more solutes, that is, the tip position of the pyramid structure can accommodate more solutes, which is beneficial to the more uniform distribution of the hole transport layer 3 of the top battery, thereby improving the efficiency of the stacked battery and better meeting actual usage needs.

[0035] like Figure 5 As shown in FIG. 1 , in a possible embodiment, the first recessed portion 22 is inclined toward the bottom cell 1. As it moves away from the bottom cell 1, the inclination angle of each first recessed portion 22 gradually decreases. The inclination angle α of the first recessed portion 22 relative to the width direction or length direction of the laminated battery is 20° to 70°. The inclination angles of the first recessed portion 22 are 20°, 25°, 30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, etc. Figure 5 As shown in the figure, the angle α3>α2>α1.

[0036] By tilting the first recess 22, the possibility of solutes in the first recess 22 flowing out of the first recess 22 can be reduced, thereby ensuring a more stable contact between the top cell and the composite layer 2. The distribution of the hole transport layer 3 of the top cell can be more uniform, which is beneficial to improving the efficiency of the stacked cell.

[0037] like Figure 3 and Figure 6 As shown, in a possible embodiment, the protrusion size of each first protrusion 21 gradually decreases in the direction approaching the bottom cell 1, and / or the first protrusion 21 is inclined in the direction away from the bottom cell 1, and the inclination angle of each first protrusion 21 gradually increases in the direction away from the bottom cell 1.

[0038] By gradually varying the size of the first protrusion 21, the first protrusion 21 near the tip of the pyramid structure of the composite layer 2 can be made larger, allowing more solute to adhere to the tip of the pyramid structure. This reduces the likelihood of solute being less at the tip and more at the base of the pyramid, facilitating improved uniformity of the hole transport layer 3 distribution. This improves the efficiency and operational stability of the stacked battery, further meeting practical requirements. The first protrusion 21 is tilted away from the bottom cell 1, facilitating solute adhesion to the surface of the composite layer 2 and reducing the impact of solute flow toward the bottom cell 1, thereby increasing the amount of solute at the tip of the pyramid structure. By tilting the first protrusion 21 away from the bottom cell 1, solute flow toward the base of the pyramid can be further hindered. The end of the first protrusion 21 away from the pyramid structure is tilted toward the side away from the bottom cell 1, facilitating solute deposition on the side of the first protrusion 21 away from the bottom cell 1, reducing the likelihood of solute flow toward the bottom cell 1 and facilitating self-adhesion to the pyramid structure and the surface of the first protrusion 21. The inclination angle of the first protrusion 21 gradually increases as it approaches the bottom cell 1. When the inclination angle is small, the side of the first protrusion 21 away from the bottom cell 1 is relatively flat, thereby providing less obstruction to the flow of solutes. When the inclination angle is large, the side of the first protrusion 21 away from the bottom cell 1 is relatively steep, thereby providing greater obstruction to the flow of solutes. By increasing the obstruction effect of the first protrusion 21 on the flow of solutes near the tip of the pyramid structure, solutes are facilitated to accumulate at the tip of the pyramid, thereby improving the uniformity of the hole transport layer 3, facilitating charge transfer, and thus improving the efficiency and operational stability of the stacked battery, more in line with actual usage requirements.

[0039] In one possible embodiment, the raised dimension of the first protrusion 21 is 10 nm to 100 nm, and / or the first protrusion 21 is tilted at an angle of 20° to 70° relative to the width or length of the laminated battery. The raised dimension of the first protrusion 21 can be 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, etc. The tilt angle of the first protrusion 21 can be 20°, 25°, 30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, etc.

[0040] When the protrusion size of the first protrusion 21 is too small, the improvement of the surface area and roughness of the composite layer 2 is small. When the protrusion size of the first protrusion 21 is too large, it is easy to cause the surface undulation of the composite layer 2 to be too large, which will affect the deposition of the top battery and affect the performance and working stability of the stacked battery.

[0041] like Figure 7 As shown, in one possible embodiment, the composite layer 2 includes a first body layer 23 and a first substrate layer 24. The first substrate layer 24 is located on a side of the first body layer 23 away from the bottom cell 1. The first protrusion 21 and / or the first recess 22 are provided on the first substrate layer 24.

[0042] The first body layer 23 serves as the main body of the composite layer 2 , and the first protrusion 21 and the first depression 22 can be directly formed on the surface of the first body layer 23 by etching or the like.

[0043] In order to maintain the integrity of the first body layer 23, a first base material layer 24 may be provided on the surface of the first body layer 23, and the first protrusion 21 and the first depression 22 may be provided on the surface of the first base material layer 24 to change the roughness of the composite layer 2. The first protrusion 21 and / or the first depression 22 may be formed by etching the first base material layer 24. Figure 8 As shown, by setting a first substrate layer 24 with uneven or discontinuous thickness on the surface of the first main layer 23, the thinner and disconnected position of the first substrate layer 24 can be used to form the first recessed portion 22, and the area with a larger thickness of the first substrate layer 24 and the first substrate layer 24 can be used to form the first protruding portion 21.

[0044] This approach can enrich the processing methods of the first protrusion 21 and the first recessed portion 22, thereby helping to reduce costs and improve processing efficiency.

[0045] In one possible embodiment, the composite layer 2 is the first transparent conductive layer, the portion of the top cell facing the composite layer 2 has a hole transport layer 3, and the roughness of the side of the composite layer 2 facing the hole transport layer 3 is 10 nm to 100 nm. The roughness of the side of the composite layer 2 facing the hole transport layer 3 can be 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, or 100 nm.

[0046] When the surface roughness of the composite layer 2 is too small, it is not conducive to the adhesion of the hole transport layer 3. During deposition, the solute easily flows to the low-lying areas on the surface of the composite layer 2, resulting in uneven thickness distribution of the hole transport layer 3, affecting the overall quality of the stacked battery. When the thickness of the composite layer 2 is too large, it is not conducive to the deposition of the perovskite layer 4. When the roughness of the composite layer 2 is too large, the surface of the composite layer 2 is too undulating, which will affect the contact between the top cell and the composite layer 2. When the structure of the top cell is prepared by the solution method, it will lead to uneven distribution of the structure of the top cell.

[0047] Based on the laminated cells provided in the above embodiments, the embodiments of the present application further provide a photovoltaic module, which includes the laminated cells involved in any of the above embodiments. Since the laminated cells have the above technical effects, the photovoltaic module including the laminated cells also has corresponding technical effects, which will not be repeated here.

[0048] The present application also provides a method for processing a laminated battery, which is used to process the laminated battery involved in the above embodiments. The method for processing the laminated battery includes: like Figure 9 As shown, S1, preparing a composite layer 2 on the bottom battery 1.

[0049] like Figure 10 As shown, S2 , the composite layer 2 is processed to form a first protrusion 21 and / or a first depression 22 on a side of the composite layer 2 away from the bottom cell 1 .

[0050] like Figure 11 As shown, S3 , a hole transport layer 3 is prepared on the side of the composite layer 2 away from the bottom cell 1 .

[0051] like Figure 12 As shown, S4, a perovskite layer 4 is prepared on the side of the hole transport layer 3 away from the composite layer 2.

[0052] like Figure 13 As shown, S5, an electron transport layer 5 is prepared on a side of the perovskite layer 4 away from the hole transport layer 3.

[0053] like Figure 14 As shown, S6, a second transparent conductive layer 6 is prepared on the side of the electron transport layer 5 away from the perovskite layer 4.

[0054] like Figure 15 As shown, S7, an electrode 8 is prepared on the side of the second transparent conductive layer 6 away from the perovskite layer 4.

[0055] like Figure 16 As shown, S8, prepare the anti-reflection layer 7.

[0056] The bottom cell 1 can be a crystalline silicon cell, and the side of the bottom cell 1 facing the composite layer 2 can have a textured layer 12. Composite layer 2, which can be a transparent conductive layer (TCO), is deposited on one side of the bottom cell 1. Composite layer 2 is a first transparent conductive layer and can be used to establish a series path between the top cell and the bottom cell 1. Composite layer 2 is processed to have a first raised portion 21 and / or a first recessed portion 22 on the side of the composite layer 2 facing the top cell. The provision of the first raised portion 21 and / or first recessed portion 22 increases the surface area of ​​the composite layer 2 facing the top cell and improves the connection stability between the composite layer 2 and the top cell, thereby improving the efficiency and operational stability of the tandem cell. A hole transport layer 3 is then formed. The increased surface roughness of the composite layer 2 facilitates solute adhesion in the hole transport layer 3, thereby improving the uniformity of the hole transport layer 3 distribution and enhancing the efficiency of the tandem cell. The perovskite layer 4, second transparent conductive layer 6, electrode 8, and anti-reflection layer 7 are then sequentially formed to produce a perovskite crystalline silicon tandem cell.

[0057] In a possible implementation, step S2 includes: S21 , forming a first protrusion 21 and / or a first depression 22 on a side of the composite layer 2 away from the bottom cell 1 by at least one of laser etching, photolithography, solution method, magnetron sputtering, spray coating, and wet chemical alkaline polishing.

[0058] The side of the composite layer 2 facing the top cell can be processed by laser etching. A laser with a power of 5W to 80W, a frequency of 500kHz to 3000kHz, and a moving speed of 3000mm / s to 30000mm / s is used to etch the composite layer 2 to a depth of no more than 100nm. For example, the laser process parameters can be set to: laser speed 1000mm / s, laser frequency 1000kHz, laser power 50W, and etching depth 50nm. After etching, the hole transport layer 3 is prepared.

[0059] The composite layer 2 can also be processed using photolithography. A thin layer of resist is applied to a portion of the composite layer 2 facing away from the bottom cell 1. The portions not covered by the resist are etched, and the resist layer is removed after etching. For example, a patterned mask can be applied to the surface of the composite layer 2. A resist (photoresist) can be sprayed onto the mask, which then adheres to the composite layer 2 through the gaps in the mask. The portions of the composite layer 2 not covered by the resist are then etched, and the resist is then removed. This can produce a surface with a certain degree of roughness.

[0060] A solution method can also be used to grow tubular, fibrous, discontinuous island-shaped structures on the side of the composite layer 2 facing the top cell to increase the roughness of the composite layer 2. The bottom cell 1 with the composite layer 2 is immersed or fumigated in a solvent containing a conductive material, or the solvent containing a conductive material is spin-coated on the side of the composite layer 2 away from the cell, and then dried. The solvent can be an organic solvent or an inorganic solvent. For example, a material that is stable and has a certain shape, such as a tubular or fibrous shape, can be dissolved in an organic solvent such as ethanol or isopropyl alcohol or an inorganic solvent such as water to form a solution. The bottom cell 1 with the composite layer 2 is immersed or fumigated in the solution, or the solution is spin-coated on the composite layer 2. After drying the solvent, a layer of tubular, fibrous or discontinuous island-shaped structures is finally covered on the surface of the composite layer 2 to give the composite layer 2 a certain degree of roughness. Aluminum oxide isopropanol solution with a particle size of 10 nm to 100 nm can be spin-coated at 3000 rpm and 1500 rpm for 30 seconds, followed by thermal annealing on a heating table for 20 minutes to remove the solvent and discretely cover the surface of the composite layer 2 with aluminum oxide nanoparticles.

[0061] Alternatively, magnetron sputtering (such as PVD or RPD) can be used with a power of 0.2 kW to 2 kW and a carrier traverse speed of 2 mm / s to 20 mm / s to deposit a conductive material with a thickness of 1 nm to 10 nm on the side of the composite layer 2 away from the bottom cell 1. The conductive material is a translucent material and can be nickel oxide, indium tungsten oxide (IWO), indium copper oxide (ICO), indium zinc oxide (IZO), or the like. For example, 5 nm of nickel oxide can be deposited at a power of 1000 W and a carrier traverse speed of 10 mm / s. Due to the thinness of the nickel oxide, it will not completely cover the surface of the composite layer 2, thus imparting a certain degree of surface roughness to the composite layer 2. Alternatively, 5 nm of indium zinc oxide can be deposited at a power of 1000 W and a carrier traverse speed of 10 mm / s.

[0062] A spraying method can also be used, in which a spray gun is used to spray a conductive material with a particle size of 10nm to 100nm onto the surface of the composite layer 2 on a heating table at a pressure of 2Bar to 10Bar for 1s to 10s, and evaporate the conductive material. The pressure of the spray gun can be 2Bar, 3Bar, 4Bar, 5Bar, 6Bar, 7Bar, 8Bar, 9Bar, 10Bar, etc. The spraying time is 1s, 2s, 3s, 4s, 5s, 6s, 7s, 8s, 9s, 10s, etc. In order to facilitate the volatilization of the solvent, the operation is usually carried out on a heating table, and the material is heated by the heating table while spraying. The temperature of the heating table can be set to 50°C to 500°C. The sprayed material can be a conductive material with a stable form, such as conductive oxides, nickel oxide, nano-aluminum oxide, etc. A 50 nm nano-alumina isopropanol solution (concentration of 10%) can be sprayed on a heating table at 200°C with a pressure of 3 Bar and a spraying time of 2 seconds. After the heating table evaporates the solvent, discretely distributed nano-alumina is formed on the composite layer 2.

[0063] Alternatively, a wet chemical alkaline polishing method may be used, wherein 2% to 10% of an etching additive is added to a 5% to 50% alkaline solution, and the composite layer 2 is etched using a tank immersion method. The alkaline solution may be potassium hydroxide, sodium hydroxide, or the like. For example, 2% of an etching additive may be added to a 20% sodium hydroxide solution, and a tank immersion method may be used to etch a groove of a certain depth on the surface of the composite layer 2.

[0064] By adopting the solution provided in the embodiment of the present application, the surface roughness of the composite layer 2 of the stacked battery facing the top battery side is relatively large, which is conducive to the attachment of the hole transport layer 3 to the composite layer 2 and increases the contact area between the composite layer 2 and the hole transport layer 3, thereby helping to improve the filling factor of the stacked battery and improve the photoelectric conversion efficiency. The increase in the number of contact points between the hole transport layer 3 and the composite layer 2 is conducive to improving the contact stability between the hole transport layer 3 and the composite layer 2, and is conducive to improving the distribution uniformity of the hole transport layer 3, thereby helping to increase the wettability of the perovskite, and is conducive to preparing a high-quality perovskite film with uniform film thickness and large grains, thereby improving the device efficiency and stability of the crystalline silicon perovskite stacked battery. The crystalline silicon perovskite stacked battery has a high photoelectric conversion efficiency. The composite layer 2 is located between the top battery and the bottom battery 1, has high conductivity and light transmittance, and at the same time, the longitudinal charge transmission speed is relatively fast. Materials such as ITO and IZO are usually used. When preparing a stacked battery, in order to make full use of the incident light, the bottom battery 1 is usually provided with a velvet layer 12, a composite layer 2 is prepared on the velvet layer 12, and then the hole transport layer 3, the perovskite layer 4 and other structures are prepared in sequence. The composite layer 2 has a conformal property, that is, the cross-sectional morphology of the composite layer 2 is consistent with the morphology of the velvet layer 12 in contact therewith. When preparing the hole transport layer 3, it is easy to cause the velvet tip to have less solute and thin thickness, and the velvet valley to have more solute and thicker thickness. By increasing the surface roughness of the composite layer 2, the solute can be hindered from flowing to the velvet valley, so that the hole transport layer 3 is evenly distributed, and it is beneficial to increase the wettability of the perovskite, which is beneficial to prepare a high-quality perovskite film with uniform film thickness and large grains, thereby improving the device efficiency and stability of the crystalline silicon perovskite stacked battery.

Claims

1. A laminated battery, characterized in that: The stacked battery comprises a bottom battery (1), a composite layer (2) and a top battery, wherein the composite layer (2) is located between the bottom battery (1) and the top battery; Wherein, a plurality of first protrusions (21) and / or a plurality of first recesses (22) are provided on a side of the composite layer (2) facing the top battery.

2. The laminated battery according to claim 1, characterized in that: The bottom battery (1) has a velvet layer (12) on a side facing the composite layer (2), and along the thickness direction of the laminated battery, the composite layer (2) is provided with a plurality of the first recessed portions (22), and / or the composite layer (2) is provided with a plurality of the first raised portions (21).

3. The laminated battery according to claim 2, characterized in that: Along a direction approaching the bottom battery (1), the width a of each first recessed portion (22) gradually decreases, and / or; The depth of the first recessed portion (22) gradually decreases in a direction approaching the bottom battery (1).

4. The stacked battery according to claim 2, characterized in that: The width of the first recessed portion (22) is 10 nm to 100 nm, and the depth of the first recessed portion (22) is 10 nm to 50 nm.

5. The laminated battery according to claim 2, characterized in that: The first recessed portion (22) is inclined in a direction approaching the bottom battery (1); In a direction away from the bottom battery (1), the inclination angle of each first recessed portion (22) gradually decreases, and / or the inclination angle of the first recessed portion (22) relative to the width direction or the length direction of the laminated battery is 20° to 70°.

6. The laminated battery according to claim 2, characterized in that: Along the direction approaching the bottom battery (1), the protrusion size of each first protrusion (21) gradually decreases, and / or; The first protrusions (21) are inclined in a direction away from the bottom battery (1), and the inclination angle of each first protrusion (21) gradually increases in the direction away from the bottom battery (1).

7. The laminated battery according to claim 2, characterized in that: The protruding size of the first protrusion (21) is 10 nm to 100 nm, and / or the inclination angle of the first protrusion (21) relative to the width direction or the length direction of the stacked battery is 20° to 70°.

8. The laminated battery according to any one of claims 1 to 7, characterized in that: The composite layer (2) comprises a first body layer (23) and a first substrate layer (24), wherein the first substrate layer (24) is located on a side of the first body layer (23) away from the bottom battery (1), and the first protrusion (21) and / or the first recess (22) are arranged on the first substrate layer (24).

9. The laminated battery according to any one of claims 1 to 7, characterized in that: The composite layer (2) is a first transparent conductive layer, the side of the top battery facing the composite layer has a hole transport layer (3), and the roughness of the side of the composite layer (2) facing the hole transport layer (3) is 10nm to 100nm.

10. A photovoltaic module, characterized in that: The photovoltaic module comprises the laminated cell according to any one of claims 1 to 9.

11. A method for processing a laminated battery, for processing the laminated battery according to any one of claims 1 to 9, characterized in that: The processing method of the stacked battery includes: Preparing a composite layer (2) on the bottom battery (1); Processing the composite layer (2) to form a first protrusion (21) and / or a first depression (22) on a side of the composite layer (2) away from the bottom battery (1); preparing a hole transport layer (3) on a side of the composite layer (2) away from the bottom battery (1); preparing a perovskite layer (4) on a side of the hole transport layer (3) away from the composite layer (2); preparing an electron transport layer (5) on a side of the perovskite layer (4) away from the hole transport layer (3); preparing a second transparent conductive layer (6) on a side of the electron transport layer (5) away from the perovskite layer (4); preparing an electrode (8) on a side of the second transparent conductive layer (6) away from the perovskite layer (4); An anti-reflection layer (7) is prepared.

12. The method for processing a stacked battery according to claim 11, wherein: The step of processing the composite layer (2) to form a first protrusion (21) and / or a first depression (22) on a side of the composite layer (2) away from the bottom battery (1) comprises: The first protrusion (21) and / or the first recess (22) are formed on a side of the composite layer (2) away from the bottom battery (1) by processing using at least one of laser etching, photolithography, solution method, magnetron sputtering, spraying, and wet chemical alkaline polishing.

13. The method for processing a stacked battery according to claim 12, wherein: The step of processing the composite layer (2) to form a first protrusion (21) and / or a first depression (22) on a side of the composite layer (2) away from the bottom battery (1) comprises: Using a laser with a power of 5W to 80W, a laser frequency of 500KHZ to 3000KHZ, and a moving speed of 3000mm / s to 30000mm / s to etch the side of the composite layer (2) away from the bottom battery (1), with the etching depth not exceeding 100nm, or; Providing a thin resist layer on a portion of the composite layer (2) on a side away from the bottom battery (1), etching the portion not covered by the thin resist layer, and then removing the thin resist layer, or; Immersing or fumigating the bottom battery (1) having the composite layer (2) in a solvent containing a conductive material, or spin-coating the solvent containing a conductive material on a side of the composite layer (2) away from the bottom battery (1), followed by drying, or; Sputtering a conductive material with a thickness of 1 nm to 10 nm on a side of the composite layer (2) away from the bottom battery (1) at a power of 0.2 KW to 2 KW and a carrier moving speed of 2 mm / s to 20 mm / s, or; The spray gun sprays a conductive material with a particle size of 10 nm to 100 nm onto the surface of the composite layer (2) on a heating platform at a pressure of 2 Bar to 10 Bar for 1 second to 10 seconds, and evaporates the conductive material, or; 2% to 10% of an etching additive is added to a 5% to 50% alkaline solution, and the composite layer (2) is etched using a tank immersion method.

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