Stacked battery structure

Abstract

This utility model relates to the field of battery technology and discloses a stacked battery structure. The stacked battery structure includes: a crystalline silicon battery; and a perovskite battery, stacked on top of the crystalline silicon battery. The area of ​​the perovskite battery is larger than that of the crystalline silicon battery. The perovskite battery includes a first light-transmitting region and a second light-transmitting region. The first light-transmitting region corresponds to at least a portion of the crystalline silicon battery. The area of ​​the perovskite battery extending beyond the crystalline silicon battery forms the second light-transmitting region. The light transmittance of the first light-transmitting region is greater than that of the second light-transmitting region, and the sheet resistance of the second light-transmitting region is less than that of the first light-transmitting region. This structure allows as much light as possible to pass through the perovskite battery to the crystalline silicon battery while minimizing the sheet resistance of the perovskite battery electrode layer. This solves the problem of limited battery efficiency caused by the high resistance of the fully transparent electrode layer in conventional stacked battery structures, thereby improving battery efficiency.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to a stacked battery structure. Background Technology

[0002] Tandem solar cells can better utilize different wavelengths of the solar spectrum, solving the absorption and heat losses of single-junction cells, thereby improving photon utilization efficiency and energy conversion efficiency of solar cells. Developing tandem solar cell technology is of great significance for promoting the development of the new energy industry.

[0003] In the existing four-terminal tandem solar cell structure, the perovskite electrode layer is often composed entirely of transparent electrodes in order to allow more light to pass through to the crystalline silicon cell and to pursue good light transmittance. Although such electrodes have good light transmittance, their electrical performance is poor, and their sheet resistance is usually large, which limits the improvement of the performance of the upper perovskite cell in the tandem solar cell and restricts the improvement of cell efficiency. Utility Model Content

[0004] In view of this, the present invention provides a stacked battery structure to solve the problem of limited efficiency improvement of stacked batteries.

[0005] This utility model provides a stacked battery structure, including: a crystalline silicon battery; and a perovskite battery, which is stacked with the crystalline silicon battery. The area of ​​the perovskite battery is larger than that of the crystalline silicon battery. The perovskite battery includes a first light-transmitting region and a second light-transmitting region. The first light-transmitting region corresponds to at least a portion of the crystalline silicon battery. The area of ​​the perovskite battery extending beyond the crystalline silicon battery forms the second light-transmitting region. The light transmittance of the first light-transmitting region is greater than that of the second light-transmitting region, and the sheet resistance of the second light-transmitting region is less than that of the first light-transmitting region.

[0006] Beneficial effects: By setting the area of ​​the perovskite cell to be larger than that of the crystalline silicon cell, the perovskite cell is divided into a first transparent area and a second transparent area with different light transmittance. The first transparent area with higher light transmittance corresponds to the crystalline silicon cell, and the second transparent area with lower light transmittance corresponds to the area below the perovskite cell where no crystalline silicon cell is placed. The first transparent area with higher light transmittance allows more light to pass through the perovskite cell and enter the crystalline silicon cell, improving the light utilization rate of the tandem cell. At the same time, the sheet resistance of the second transparent area is lower than that of the first transparent area, which can reduce the overall sheet resistance of the perovskite cell electrode layer. This achieves the goal of allowing more light to pass through the perovskite cell and enter the crystalline silicon cell while minimizing the sheet resistance of the perovskite cell electrode layer. This solves the problem that the high resistance of the fully transparent electrode layer in conventional tandem cell structures limits the improvement of cell efficiency, thereby improving cell efficiency.

[0007] In one optional embodiment, the perovskite solar cell includes a back electrode disposed near the crystalline silicon solar cell. The back electrode includes a transparent electrode layer and a metal conductive layer. The metal conductive layer covers a portion of the transparent electrode layer. The portion of the transparent electrode layer not covered by the metal conductive layer corresponds to the first light-transmitting area. The metal conductive layer and the portion of the transparent electrode layer it covers form a composite electrode area. The composite electrode area includes at least a first composite electrode area disposed corresponding to the second light-transmitting area.

[0008] Beneficial effects: By partitioning the back electrode, the high light transmittance of the first light-transmitting area is ensured, allowing more light to pass through and reach the crystalline silicon cell. At the same time, the sheet resistance of the back electrode corresponding to the second light-transmitting area is reduced by using a metal conductive layer, thereby reducing the series resistance of the perovskite cell, improving the conductivity of the perovskite cell, and thus improving the photoelectric conversion efficiency of the entire stacked cell structure and increasing the fill factor of the cell.

[0009] In one optional embodiment, the transparent electrode layer is made of ITO; And / or, the material of the metal conductive layer includes one of copper, aluminum, and molybdenum.

[0010] Beneficial effects: ITO has good light transmittance and certain conductivity, which can meet the light transmittance requirements of the first light-transmitting area, while providing basic conductivity for the back electrode; And / or, metals such as copper, aluminum, and molybdenum have excellent electrical conductivity, which can effectively reduce the sheet resistance of the composite electrode region, thereby reducing the sheet resistance of the back electrode and improving battery efficiency.

[0011] In one optional embodiment, the thickness of the transparent electrode layer is 30 nm to 150 nm; And / or, the thickness of the metal conductive layer is 50 nm to 100 nm.

[0012] Beneficial effects: By setting the thickness of the transparent electrode layer in the range of 30 nm to 150 nm, it is possible to ensure that the transparent electrode layer has a certain degree of light transmittance while maintaining its basic conductivity. And / or, setting the thickness of the metal conductive layer in the range of 50 nm to 100 nm can ensure good conductivity of the back electrode while taking into account cost and ensuring the light transmittance of the perovskite solar cell.

[0013] In one optional embodiment, the crystalline silicon solar cell includes a light-absorbing region and grid lines, wherein the orthographic projection of the light-absorbing region onto the perovskite solar cell corresponds directly to the first light-transmitting region.

[0014] Beneficial effects: By setting the orthogonal projection of the light-absorbing area on the perovskite solar cell to correspond directly with the first light-transmitting area, the light-absorbing area can receive the light entering the crystalline silicon solar cell through the first light-transmitting area to the maximum extent, thereby improving the light absorption efficiency and thus enhancing the photoelectric conversion capability of the crystalline silicon solar cell, which helps to improve the efficiency of the entire stacked solar cell structure.

[0015] In one optional embodiment, the perovskite solar cell further includes a third light-transmitting region located in the orthogonal projection region of the grid line on the back electrode, and the composite electrode region further includes a second composite electrode region corresponding to the third light-transmitting region.

[0016] Beneficial effects: By setting a third light-transmitting region in the perovskite cell that is at least partially opposite to the grid lines of the crystalline silicon cell, and the area of ​​the back electrode within the range of the third light-transmitting region being a second composite electrode region composed of a transparent electrode layer and a metal conductive layer, which has high conductivity, the sheet resistance of the back electrode can be further reduced without blocking the light transmitted to the light-absorbing region of the crystalline silicon cell. This allows more light to pass through the perovskite cell to reach the light-absorbing region of the crystalline silicon cell, thereby further improving the photoelectric conversion efficiency of the entire stacked cell structure.

[0017] In one optional embodiment, the perovskite solar cell includes a plurality of sub-cells, the plurality of sub-cells being separated by sub-cell scribing lines, the length direction of the grid lines being consistent with the length direction of the sub-cell scribing lines.

[0018] Beneficial effects: By setting the length direction of the grid lines to be consistent with the length direction of the sub-cell scribe lines used to divide the sub-cells in the perovskite solar cell, the grid line layout of the crystalline silicon solar cell can be matched with the sub-cell division of the perovskite solar cell, thereby further improving the photoelectric conversion efficiency of the tandem solar cell structure.

[0019] In one alternative embodiment, the orthographic projection of the grid lines on the perovskite solar cell partially or completely overlaps with the scribing lines of the sub-cell.

[0020] Beneficial effects: By aligning the grid lines with the sub-cell scribe lines, the light passing through the first light-transmitting area can act on the light-absorbing area of ​​the crystalline silicon cell as much as possible, thereby further ensuring that the light-absorbing area of ​​the crystalline silicon cell can absorb as much light as possible, and further improving the photoelectric conversion efficiency of the tandem cell structure.

[0021] In one optional embodiment, the stacked battery structure further includes: a front glass panel disposed on the side of the perovskite battery facing away from the crystalline silicon battery; a back glass panel disposed on the side of the crystalline silicon battery facing away from the perovskite battery; a first encapsulating film disposed between the perovskite battery and the crystalline silicon battery; a second encapsulating film disposed between the crystalline silicon battery and the back glass panel; and a sealant disposed between the front glass panel and the back glass panel, and located at the circumferential edges of the front glass panel and the back glass panel.

[0022] Beneficial effects: The front and back glass panels provide physical protection for the battery, preventing damage to the internal structure from external environmental factors; the first and second encapsulating films act as adhesives and sealants, preventing moisture, oxygen, and other substances from entering the battery and affecting its performance; the sealant further enhances the battery's sealing performance along its edges. The sealant, together with the front and back glass panels, forms a sealed space to accommodate the crystalline silicon and perovskite batteries, ensuring the stability and reliability of the stacked battery structure during long-term use.

[0023] In one optional embodiment, the perovskite solar cell further includes a front electrode disposed on the front glass plate, and a first positioning point is provided on the front electrode.

[0024] Beneficial effects: The establishment of the first positioning point helps to accurately position the stacked battery structure during production and assembly, improves production efficiency and product quality, ensures that each component can be accurately installed and connected, and guarantees the stability of the overall structural performance. Attached Figure Description

[0025] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of a stacked battery structure according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a perovskite battery according to an embodiment of the present invention; Figure 3 This is a P1 etching morphology diagram of a perovskite solar cell according to an embodiment of the present invention. Figure 4 This is a schematic diagram of the patterned etching morphology of a local area on a perovskite solar cell according to an embodiment of the present invention. Figure 5This is a schematic diagram showing the placement of an insulating layer on a perovskite solar cell according to an embodiment of the present invention. Figure 6 This is a top view schematic diagram of the overall structure of a stacked battery according to an embodiment of the present utility model; Figure 7 for Figure 6 A magnified view of part A in the diagram.

[0027] Explanation of reference numerals in the attached figures: 10. Crystalline silicon solar cell; 11. Light-absorbing area; 12. Grid line; 20. Perovskite solar cell; 201. First light-transmitting area; 202. Second light-transmitting area; 203. Third light-transmitting area; 21. Back electrode; 211. Transparent electrode layer; 212. Metal conductive layer; 22. Front electrode; 221. First positioning point; 23. First charge transport layer; 24. Perovskite layer; 25. Second charge transport layer; 30. Front glass; 40. Back glass; 51. First encapsulating film; 52. Second encapsulating film; 53. Sealant; 60. Insulating layer; 601. Second positioning point; 71. Solder ribbon; 72. Busbar; 81. First scribing line; 82. Second scribing line; 83. Third scribing line; 84. Insulating line; 85. Edge cleaning area. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0029] Currently, mainstream N-type crystalline silicon solar cells on the market, such as Topcon (Tunnel Oxide Passivated Contact) cells, generally have efficiencies exceeding 81%, approaching the Shockley-Queisser limit, making further breakthroughs extremely difficult. Compared to crystalline silicon cells, tandem cells can better utilize different wavelengths of the solar spectrum, solving the absorption and heat losses of single-junction cells, thereby improving photon utilization efficiency and solar cell energy conversion efficiency. Theoretical calculations show that the theoretical efficiency of double-junction tandem cells can reach over 46%, far exceeding the 33% efficiency limit of single-junction cells. Therefore, developing tandem cell technology is of great significance for promoting the development of the new energy industry. In existing four-terminal tandem cell structures, the perovskite electrode layer is often composed of transparent electrodes to allow more light to transmit to the crystalline silicon cell. While these electrodes have good light transmittance, their electrical performance is poor, with a sheet resistance typically between 30-50Ω, which limits the performance improvement of the upper perovskite cell in tandem cells. This perovskite solar cell structure, composed entirely of highly transparent electrodes, is significantly affected by the electrical properties of the transparent electrodes, limiting its efficiency improvement. It should be noted that the efficiency mentioned refers to photoelectric conversion efficiency.

[0030] The following is combined with Figures 1 to 7 The following describes embodiments of the present invention.

[0031] According to an embodiment of the present invention, a stacked battery structure is provided, comprising: a crystalline silicon battery 10 and a perovskite battery 20. The perovskite battery 20 and the crystalline silicon battery 10 are stacked together, the area of ​​the perovskite battery 20 is larger than the area of ​​the crystalline silicon battery 10, the perovskite battery 20 includes a first light-transmitting region 201 and a second light-transmitting region 202, the first light-transmitting region 201 corresponds to at least a portion of the crystalline silicon battery 10, the area of ​​the perovskite battery 20 extending beyond the crystalline silicon battery 10 forms the second light-transmitting region 202, the transmittance of the first light-transmitting region 201 is greater than the transmittance of the second light-transmitting region 202, and the sheet resistance of the second light-transmitting region 202 is less than the sheet resistance of the first light-transmitting region 201.

[0032] By applying the tandem battery structure of this embodiment, and setting the area of ​​the perovskite battery 20 to be larger than that of the crystalline silicon battery 10, the perovskite battery 20 is divided into a first transparent region 201 and a second transparent region 202 with different transmittance. The first transparent region 201 with higher transmittance corresponds to the crystalline silicon battery 10, and the second transparent region 202 with lower transmittance corresponds to the area below the perovskite battery 20 where no crystalline silicon battery 10 is placed. Thus, the first transparent region 201 with higher transmittance allows more light to pass through the perovskite battery 20 and enter the crystalline silicon battery 10, improving the light utilization rate of the tandem battery. At the same time, the sheet resistance of the second transparent region 202 is lower than that of the first transparent region 201, which can reduce the overall sheet resistance of the electrode layer of the perovskite battery 20. This achieves the goal of allowing more light to pass through the perovskite battery and enter the crystalline silicon battery while minimizing the sheet resistance of the perovskite battery electrode layer, solving the problem that the high resistance of the fully transparent electrode layer in conventional tandem battery structures limits the improvement of battery efficiency, thereby improving battery efficiency.

[0033] It should be noted that both the perovskite solar cell 20 and the crystalline silicon solar cell 10 are sheet-like, and the area of ​​the cell refers to the surface area of ​​the surface perpendicular to the thickness direction of the cell; the sheet resistance of the first light-transmitting region 201 refers to the sheet resistance of the area corresponding to the first light-transmitting region 201 on the electrode layer of the perovskite solar cell 20, and the sheet resistance of the second light-transmitting region 202 refers to the sheet resistance of the area corresponding to the second light-transmitting region 202 on the electrode layer of the perovskite solar cell 20; the improved cell efficiency only refers to the improved photoelectric conversion efficiency.

[0034] In one embodiment, the perovskite solar cell 20 includes a back electrode 21 disposed near the crystalline silicon solar cell 10. The back electrode 21 includes a transparent electrode layer 211 and a metal conductive layer 212. The metal conductive layer 212 covers a portion of the transparent electrode layer 211. The portion of the transparent electrode layer 211 not covered by the metal conductive layer 212 corresponds to a first light-transmitting region 201. The metal conductive layer 212 and the portion of the transparent electrode layer 211 it covers form a composite electrode region. The composite electrode region includes at least a first composite electrode region disposed corresponding to a second light-transmitting region 202. It should be noted that the area on the transparent electrode layer 211 not covered by the metal conductive layer 212 is the high light transmittance area of ​​the back electrode 21, and the area on the transparent electrode layer 211 covered by the metal conductive layer 212 is the low light transmittance area. That is, the back electrode portion located in the first light transmittance area 201 only has a transparent electrode layer, and the back electrode portion located in the second light transmittance area 202 includes a transparent electrode layer and a metal conductive layer. The composite electrode region has a lower sheet resistance due to the addition of the metal conductive layer 212, while the first light transmittance area 201 has higher light transmittance because it only has the transparent electrode layer 211. Thus, by partitioning the back electrode 21, the high light transmittance of the first light transmittance area 201 is ensured, allowing more light to pass through and reach the crystalline silicon cell 10. At the same time, the sheet resistance of the back electrode corresponding to the second light transmittance area 202 is reduced by using the metal conductive layer 212, thereby reducing the series resistance of the perovskite cell, improving the conductivity of the perovskite cell 20, and thus improving the photoelectric conversion efficiency of the entire stacked cell structure and increasing the fill factor of the cell.

[0035] Among them, the fill factor is one of the core key parameters for measuring the energy conversion efficiency and output performance of a battery. It essentially describes the difference between the actual output power of the battery and the theoretical maximum possible output power, and directly reflects the quality of the battery's core performance such as internal resistance and charge transport efficiency.

[0036] In one embodiment, the transparent electrode layer 211 is made of ITO (Indium Tungsten Oxide). ITO has good light transmittance and certain conductivity, which can meet the light transmittance requirements of the first light-transmitting area 201, and at the same time provide basic conductivity for the back electrode 21.

[0037] In one embodiment, the metal conductive layer 212 is made of one of copper, aluminum, or molybdenum. Copper, aluminum, and molybdenum are metals with excellent conductivity, which can effectively reduce the sheet resistance of the composite electrode region, thereby reducing the sheet resistance of the back electrode 21 and improving battery efficiency. Of course, the metal conductive layer 212 can also be made of other metals with good conductivity.

[0038] In one embodiment, the thickness of the transparent electrode layer 211 is 30 nm to 150 nm. If the thickness of the transparent electrode layer 211 is less than 30 nm, its light transmittance may be further improved, but its conductivity will decrease significantly, making it difficult to meet the basic conductivity requirements of the back electrode 21. If the thickness of the transparent electrode layer is greater than 150 nm, it will reduce the light transmittance of the first light-transmitting region 201, affecting the amount of light passing through the perovskite cell 20 to reach the crystalline silicon cell 10, and thus affecting the light utilization rate of the tandem cell structure. Therefore, by setting the thickness of the transparent electrode layer 211 in the range of 30 nm to 150 nm, it is possible to ensure that the transparent electrode layer 211 has a certain degree of light transmittance while maintaining its basic conductivity function.

[0039] In one embodiment, the thickness of the metal conductive layer 212 is 50 nm to 100 nm. If the thickness of the metal conductive layer 212 is less than 50 nm, its conductivity is poor, making it difficult to effectively reduce the sheet resistance of the composite electrode region. If the thickness of the metal conductive layer 212 is greater than 100 nm, although the conductivity will be further improved, it will increase the material cost. Furthermore, an excessively thick metal conductive layer 212 will result in excessively low light transmittance of the second light-transmitting region 202 and an excessively large thickness of the stacked battery structure. Therefore, setting the thickness of the metal conductive layer 212 in the range of 50 nm to 100 nm can ensure good conductivity of the back electrode 21 while also considering cost and ensuring the light transmittance of the perovskite battery 20.

[0040] In one embodiment, the crystalline silicon solar cell 10 includes a light-absorbing region 11 and a grid line 12. The orthographic projection of the light-absorbing region 11 onto the perovskite solar cell 20 corresponds directly to the first light-transmitting region 201. It should be noted that the light-absorbing region 11 of the crystalline silicon solar cell 10 is the region in the crystalline silicon solar cell 10 that actually absorbs light and generates photogenerated carriers. By setting the orthographic projection of the light-absorbing region 11 onto the perovskite solar cell 20 to correspond directly to the first light-transmitting region 201, the light-absorbing region 11 can receive the light entering the crystalline silicon solar cell 10 through the first light-transmitting region 201 to the maximum extent, improving the light absorption efficiency and thus enhancing the photoelectric conversion capability of the crystalline silicon solar cell, which contributes to the improvement of the overall efficiency of the tandem solar cell structure.

[0041] In one embodiment, the perovskite solar cell 20 further includes a third light-transmitting region 203, which is located in the orthogonal projection region of the grid line 12 onto the back electrode 21. The composite electrode region also includes a second composite electrode region, which is correspondingly disposed to the third light-transmitting region 203. It should be noted that the grid line 12 is a conductive line of the crystalline silicon solar cell 10, used to collect and transmit photogenerated carriers, and does not absorb light itself. The second composite electrode region of the perovskite solar cell 20, like the first composite electrode region, consists of a partially transparent electrode layer 211 and a partially conductive metal layer 212 covering it, and has low light transmittance and high conductivity. Therefore, by setting the perovskite cell 20 to also have a third light-transmitting region 203 that is directly opposite to at least a portion of the grid lines 12 of the crystalline silicon cell 10, and the area of ​​the back electrode 21 located within the third light-transmitting region 203 is a second composite electrode region composed of a transparent electrode layer and a metal conductive layer, which has high conductivity, it can further reduce the sheet resistance of the back electrode 21 without blocking the light transmitted to the light-absorbing region 11 of the crystalline silicon cell 10, thereby allowing more light to pass through the perovskite cell 20 to reach the light-absorbing region 11 of the crystalline silicon cell 10, thereby further improving the photoelectric conversion efficiency of the entire stacked cell structure.

[0042] In one embodiment, the perovskite solar cell 20 includes a plurality of sub-cells separated by sub-cell scribing lines, and the length direction of the grid line 12 is consistent with the length direction of the sub-cell scribing lines. The sub-cell scribing lines mentioned in this invention refer to the P1 line (i.e., the first scribing line 81), P2 line (i.e., the second scribing line 82), and P3 line (i.e., the third scribing line 83) used in the perovskite solar cell to form an electrical series connection between two adjacent sub-cells. This can also be understood as a scribing area, which is the basic structure of the perovskite solar cell and is existing technology, so it will not be elaborated further here. By setting the length direction of the grid line 12 to be consistent with the length direction of the sub-cell scribing lines used to divide the plurality of sub-cells in the perovskite solar cell 20, the grid line layout of the crystalline silicon solar cell 10 can be matched with the sub-cell division of the perovskite solar cell 20, so that the light transmitted through the first light-transmitting area 201 can act on the light-absorbing area 11 of the crystalline silicon solar cell 10 as much as possible, thereby further improving the photoelectric conversion efficiency of the tandem solar cell structure. The length direction refers to the extension direction of the first scribe line 81, specifically... Figure 6 The direction of the "X" indicated by the middle arrow.

[0043] In one embodiment, the orthographic projection of the grid line 12 on the perovskite cell 20 partially or completely overlaps with the scribing line of the sub-cell, so that the grid line 12 and the scribing line of the sub-cell are directly opposite each other. This allows the light passing through the first light-transmitting area 201 to act on the light-absorbing area 11 of the crystalline silicon cell 10 as much as possible, thereby further ensuring that the light-absorbing area 11 of the crystalline silicon cell 10 can absorb as much light as possible, and further improving the photoelectric conversion efficiency of the stacked cell structure.

[0044] In one embodiment, the stacked battery structure further includes: a front glass panel 30, a back glass panel 40, a first encapsulating film 51, a second encapsulating film 52, and a sealant 53. The front glass panel 30 is disposed on the side of the perovskite battery 20 opposite to the crystalline silicon battery 10; the back glass panel 40 is disposed on the side of the crystalline silicon battery 10 opposite to the perovskite battery 20; the first encapsulating film 51 is disposed between the perovskite battery 20 and the crystalline silicon battery 10; the second encapsulating film 52 is disposed between the crystalline silicon battery 10 and the back glass panel 40; and the sealant 53 is disposed between the front glass panel 30 and the back glass panel 40, and is located at the circumferential edges of the front glass panel 30 and the back glass panel 40. The front glass 30 and the back glass 40 provide physical protection for the battery, preventing external environmental factors from damaging the internal structure of the battery. The first encapsulating film 51 and the second encapsulating film 52 play a bonding and sealing role, preventing moisture, oxygen and other substances from entering the battery and affecting its performance. The sealant 53 further enhances the battery's sealing performance along the battery edge. The sealant 53, together with the front glass 30 and the back glass 40, form a sealed space to accommodate the crystalline silicon battery 10 and the perovskite battery 20, ensuring the stability and reliability of the stacked battery structure during long-term use.

[0045] In one embodiment, both the first encapsulating film 51 and the second encapsulating film 52 are POE (Polyolefin Elastomer) films, which have advantages such as high barrier properties and aging resistance.

[0046] In one embodiment, the perovskite solar cell 20 further includes a front electrode 22 disposed on the front glass 30, and a first positioning point 221 is provided on the front electrode 22. The first positioning point 221 helps to accurately position the cells during the production and assembly of the stacked cell structure, improves production efficiency and product quality, ensures that the components can be accurately installed and connected, and guarantees the stability of the overall structural performance.

[0047] In one embodiment, the perovskite cell 20 further includes an insulating layer 60. The insulating layer 60 is disposed on the side of the first encapsulating film 51 opposite to the perovskite cell 20. The insulating layer 60 is in the shape of a narrow strip, and there are two insulating layers 60, which are disposed at both ends of the crystalline silicon cell 10. The side of the insulating layer 60 opposite to the perovskite cell 20 is provided with the crystalline silicon cell 10 and its solder ribbons 71. The insulating layer 60 serves as an insulating isolation layer in the stacked encapsulation to prevent the solder ribbons 71 at both ends of the crystalline silicon cell 10 from penetrating the first encapsulating film 51 and causing a short circuit during the lamination process, thereby ensuring the safe operation of the internal circuit of the battery.

[0048] In one embodiment, the insulating layer 60 is an ETFE film (Ethylene-Tetrafluoroethylene Copolymer), which has high weather resistance, high transparency, and insulation.

[0049] In one embodiment, a first positioning point 221 on the front electrode 22 is used to provide positioning for the insulating layer 60; a second positioning point 601 is provided on the insulating layer 60, which provides positioning for the placement of the crystalline silicon cell 10. During the cell encapsulation process, the insulating layer 60 is placed on the first positioning point 221, and the crystalline silicon cell 10 is placed on the second positioning point 601 of the insulating layer 60, as shown in the specific structure. Figure 4 As shown.

[0050] In one embodiment, the stacked battery structure further includes a busbar 72, and the number of solder ribbons 71 is several. The solder ribbons 71 are connected to the grid lines 12 of the crystalline silicon battery 10, and the busbar 72 is connected to the solder ribbons 71.

[0051] In one embodiment, the busbar 72 is independently led out as an electrode of the perovskite cell, and the solder ribbon 71 is independently led out as an electrode of the crystalline silicon cell, forming a four-terminal stacked cell.

[0052] It should be noted that the perovskite cell 20 is a 300mm×300mm module, which is the main product of the laboratory, while the crystalline silicon cell 10 is a mainstream 210mm×210mm Topcon cell. The insulating layer 60 used in the encapsulation process is an ETFE film with cross-shaped Mark points (i.e., the second positioning point 602).

[0053] The assembly process of the perovskite solar cell 20 is as follows: 1. Clean the FTO glass and perform P1 etching to form the first scribing line 81. Compared with conventional perovskite solar cells, the first scribing line 81 in this embodiment has first positioning points 221 (e.g., positioning points 221 for ETFE film positions) added to both sides of the original etching line. Figure 3 (as shown); wherein, the FTO glass includes a front plate glass 30 and a front electrode 22, the front electrode 22 being FTO (Fluorine-doped Tin Oxide). 2. After P1 etching is completed, the surface is cleaned again, and a layer of NiOx (Nickel Oxide) is sputtered on the surface as the first charge transport layer 23, followed by the coating of the perovskite layer 24. 3. A layer of C60 (carbon 60) is sequentially deposited by physical vapor deposition and a layer of IWO (indium tungsten oxide) is deposited by reactive plasma deposition on the perovskite layer 24. C60 and IWO together constitute the ETL layer (Electron Transport Layer), i.e. the second charge transport layer 25. After the ETL layer is prepared, the component is etched by P2 to form the second scribing line 82. 4. First, a high-transparency transparent electrode layer 211 is sputtered on the IWO layer, and then a metal layer is sputtered; 5. Perform P3 etching (to form the third scribing line 83) and patterning etching on the component. The P3 etching and patterning etching share a common alignment point, and alignment is only required once. The patterning etching removes the metal in the area corresponding to the first transparent area 201, dividing the back electrode 21 of the entire perovskite cell 20 into a transparent / metal electrode area (i.e., a composite electrode area) and a transparent electrode area (e.g., a metal electrode area). Figure 4 As shown in the figure, the composite electrode region corresponds to the second light-transmitting region 202, and the transparent electrode region corresponds to the first light-transmitting region 201; 6. Perform P4 edge clearing etching and encapsulation on the module, forming an insulating line 84 on the perovskite cell 20. The area outside the insulating line 84 is the edge clearing area 85. During the encapsulation process, the insulating layer 60 is placed on the first positioning point 221 left by P1, and the crystalline silicon cell 10 is placed on the second positioning point 601 on the insulating layer 60 (e.g., ...). Figure 5 As shown), the overall structure of the stacked battery structure is as follows: Figure 6 As shown.

[0054] Preferably, the stacked battery structure in this embodiment is a four-terminal stacked perovskite battery structure.

[0055] In this embodiment, the four-terminal stacked perovskite solar cell structure divides the back electrode 21 of the perovskite solar cell 20 into two regions: a transparent electrode region and a transparent / metal electrode region. The transparent electrode region corresponds to the light-absorbing region 11 of the crystalline silicon solar cell 10; the transparent / metal electrode region corresponds to the grid line 12 of the crystalline silicon solar cell 10 and the area below the perovskite solar cell where no crystalline silicon solar cell 10 is placed. While allowing more light to pass through the perovskite solar cell 20 and enter the crystalline silicon solar cell 10, the sheet resistance of the electrode layer of the perovskite solar cell 20 is reduced as much as possible, thereby improving efficiency.

[0056] In this embodiment, the stacked battery structure is mainly fabricated using dual-positioning laser patterning etching. Positioning is achieved by using the first positioning point 221 left during P1 etching and the second positioning point 601 on the insulating layer 60, ensuring the accuracy of the patterning etching. Compared with conventional mask patterning sputtering, the dual-positioning laser patterning etching used in this embodiment causes less damage to the perovskite battery and is more flexible.

[0057] It should be noted that traditional mask patterning sputtering involves placing the mask over the perovskite solar cell, which comes into contact with the electrode layer. During cell loading and unloading, friction occurs between the mask and the electrodes, potentially damaging them. Furthermore, a single mask can only correspond to a specific perovskite or crystalline silicon solar cell; if even a slight change occurs in either type, the mask must be discarded, which is extremely inconvenient. In contrast, the dual-positioning laser patterning etching method used in this embodiment causes less damage to the perovskite module (no contact with the module is required) and is more flexible (the etching position can be freely adjusted according to the type of cell). Additionally, the sputtering of the transparent electrode and the metal electrode can be combined into a single sputtering operation, and the P3 etching process for the perovskite module can be combined with the patterning etching into a single etching step, significantly improving production efficiency.

[0058] The stacked battery structure of this embodiment uses the moltenness of the adhesive film as a buffer layer to reduce the damage to the perovskite film surface during the lamination process of the crystalline silicon battery; it provides a simple encapsulation method by filling the gaps in the crystalline silicon module with the moltenness of the adhesive film, preventing the crystalline silicon module from breaking during the lamination process, thereby avoiding affecting the photoelectric performance of the entire battery.

[0059] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A stacked battery structure, characterized in that, include: Crystalline silicon solar cell (10); A perovskite solar cell (20) is stacked with the crystalline silicon solar cell (10). The area of ​​the perovskite solar cell (20) is larger than the area of ​​the crystalline silicon solar cell (10). The perovskite solar cell (20) includes a first light-transmitting area (201) and a second light-transmitting area (202). The first light-transmitting area (201) corresponds to at least a portion of the crystalline silicon solar cell (10). The area of ​​the perovskite solar cell (20) that extends beyond the crystalline silicon solar cell (10) forms the second light-transmitting area (202). The transmittance of the first light-transmitting area (201) is greater than the transmittance of the second light-transmitting area (202), and the sheet resistance of the second light-transmitting area (202) is less than the sheet resistance of the first light-transmitting area (201).

2. The stacked battery structure according to claim 1, characterized in that, The perovskite solar cell (20) includes a back electrode (21) disposed near the crystalline silicon solar cell (10). The back electrode (21) includes a transparent electrode layer (211) and a metal conductive layer (212). The metal conductive layer (212) covers a portion of the transparent electrode layer (211). The portion of the transparent electrode layer (211) that is not covered by the metal conductive layer (212) corresponds to the first light-transmitting area (201). The metal conductive layer (212) and the portion of the transparent electrode layer (211) it covers form a composite electrode area. The composite electrode area includes at least a first composite electrode area that corresponds to the second light-transmitting area (202).

3. The stacked battery structure according to claim 2, characterized in that, The transparent electrode layer (211) is made of ITO; And / or, the material of the metal conductive layer (212) includes one of copper, aluminum, and molybdenum.

4. The stacked battery structure according to claim 2, characterized in that, The thickness of the transparent electrode layer (211) is 30 nm to 150 nm; And / or, the thickness of the metal conductive layer (212) is 50 nm to 100 nm.

5. The stacked battery structure according to claim 2, characterized in that, The crystalline silicon cell (10) includes a light-absorbing region (11) and a grid line (12). The orthogonal projection of the light-absorbing region (11) onto the perovskite cell (20) corresponds to the first light-transmitting region (201).

6. The stacked battery structure according to claim 5, characterized in that, The perovskite solar cell (20) further includes a third light-transmitting area (203), which is located in the positive projection area of ​​the grid line (12) on the back electrode (21). The composite electrode area further includes a second composite electrode area, which is correspondingly arranged with the third light-transmitting area (203).

7. The stacked battery structure according to claim 5, characterized in that, The perovskite solar cell (20) includes a plurality of sub-cells, which are separated by sub-cell scribe lines, and the length direction of the grid line (12) is consistent with the length direction of the sub-cell scribe lines.

8. The stacked battery structure according to claim 7, characterized in that, The orthographic projection of the grid line (12) on the perovskite cell (20) partially or completely overlaps with the scribing line of the sub-cell.

9. The stacked battery structure according to any one of claims 1 to 8, characterized in that, The stacked battery structure also includes: The front glass (30) is disposed on the side of the perovskite cell (20) opposite to the crystalline silicon cell (10); A backplate glass (40) is disposed on the side of the crystalline silicon cell (10) away from the perovskite cell (20); A first encapsulating film (51) is disposed between the perovskite cell (20) and the crystalline silicon cell (10); The second encapsulating film (52) is disposed between the crystalline silicon cell (10) and the backplate glass (40); The sealant (53) is disposed between the front glass (30) and the back glass (40), and is located at the circumferential edges of the front glass (30) and the back glass (40).

10. The stacked battery structure according to claim 9, characterized in that, The perovskite solar cell (20) also includes a front electrode (22), which is disposed on the front glass (30) and has a first positioning point (221).

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