Laser annealing method of solar cell grid line and application of laser annealing method

Abstract

The invention provides a laser annealing method of a solar cell grid line and application thereof. The laser annealing method comprises the following steps that a solar cell is placed on a water cooling table, and a grid line electrode is arranged on the surface of the side, away from the water cooling table, of the solar cell; and carrying out annealing treatment on the grid line electrode by adopting laser. The invention designs an annealing method combining laser annealing and battery water cooling, and the method not only can reduce the annealing energy consumption and shorten the annealing time, but also can improve the conductivity of the grid line electrode, and reduces the thermal damage to each functional layer in the solar battery in the annealing process under the condition of ensuring that the high-quality grid line electrode is obtained. Moreover, the method can also improve the interface quality between the grid line electrode and each functional layer, and improves the long-term stability and reliability of the solar cell.

Description

Technical Field

[0001] This invention belongs to the field of photovoltaic technology, specifically relating to a laser annealing method for solar cell grid lines and its application. Background Technology

[0002] Perovskite-crystalline silicon tandem solar cell technology has attracted widespread attention since 2014, aiming to break through the efficiency limit of single-cell solar cells by combining the high light absorption efficiency of perovskite materials with the stability of crystalline silicon. With more detailed research on materials for the electron transport layer and hole transport layer of perovskite solar cells, significant progress has been made in both single-cell and tandem cells. Currently, the efficiency of perovskite-crystalline silicon tandem solar cells has reached as high as 34.6%.

[0003] However, whether it's a single-cell or tandem cell, annealing with a hot plate is frequently used during the fabrication process to improve material performance. For example, after spin-coating the perovskite layer, heating is needed to accelerate perovskite crystallization, and annealing is also required after preparing the hole layer (nickel oxide) to improve film performance. Although annealing can improve some photoelectric properties of the perovskite layer or other functional layers, it also causes thermal damage to the battery, thus reducing battery efficiency. In addition, traditional thermal annealing methods have disadvantages such as high energy consumption and long annealing time, which are not conducive to large-scale mass production.

[0004] Therefore, how to solve the problems of high energy consumption, long annealing time and easy thermal damage in annealing is a current research hotspot. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide a laser annealing method for solar cell grid lines and its application. This invention designs an annealing method combining laser annealing and battery water cooling. This method not only reduces annealing energy consumption and annealing time but also improves the conductivity of the grid line electrodes, ensuring high-quality grid line electrodes while minimizing thermal damage to the functional layers of the solar cell during the annealing process. Furthermore, this method can improve the interface quality between the grid line electrodes and the functional layers, thereby enhancing the long-term stability and reliability of the solar cell.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] In a first aspect, the present invention provides a laser annealing method for solar cell grid lines, the laser annealing method comprising the following steps:

[0008] A solar cell is placed on a water-cooled platform, and the surface of the solar cell away from the water-cooled platform has grid line electrodes.

[0009] The grid line electrodes are annealed using a laser.

[0010] This invention presents an annealing method combining laser annealing and battery water cooling. This method not only reduces annealing energy consumption and time but also improves the conductivity of the grid electrodes, ensuring high-quality grid electrodes while minimizing thermal damage to the functional layers of the solar cell during annealing. Furthermore, this method improves the interface quality between the grid electrodes and the functional layers, enhancing the long-term stability and reliability of the solar cell.

[0011] It's important to note that a water-cooled platform is a cooling device that uses the circulation of a liquid (usually water or a special coolant) to absorb and remove heat. Its basic principle is based on heat transfer. When the temperature of the object being cooled (such as electronic equipment or heat-generating components of industrial machinery) is higher than the temperature of the circulating liquid, heat is transferred from the object to the liquid. Then, the heat-carrying liquid circulates through the heat dissipation components (such as radiators) of the water-cooled platform via a pump or other power source, transferring the heat from the liquid to the surrounding environment, thereby cooling the object.

[0012] Preferably, the solar cell comprises a perovskite-crystalline silicon tandem solar cell.

[0013] Preferably, the perovskite-crystalline silicon tandem solar cell includes a crystalline silicon bottom cell, a tunneling composite layer, and a perovskite top cell stacked together.

[0014] Preferably, the crystalline silicon bottom cell includes a heterojunction cell or a TOPCon (tunneling oxide passivated contact) cell.

[0015] Preferably, the heterojunction cell includes, along the direction close to the tunneling composite layer, a stacked back conductive metal electrode, a back transparent conductive layer, a p-type amorphous silicon layer, a first intrinsic amorphous silicon layer, a silicon wafer, a second intrinsic amorphous silicon layer, and an n-type amorphous silicon layer.

[0016] Preferably, the material of the back conductive metal electrode includes Ag.

[0017] Preferably, the material of the transparent conductive layer on the back includes ITO (indium tin oxide).

[0018] Preferably, the tunneling composite layer comprises an ITO composite layer.

[0019] Preferably, the perovskite top cell includes a first charge transport layer, a perovskite light-absorbing layer, a second charge transport layer, and a grid electrode stacked together along the direction away from the tunneling composite layer.

[0020] Preferably, the charges transported by the first charge transport layer and the second charge transport layer are of opposite polarity.

[0021] Preferably, the first charge transport layer is a hole transport layer, and the second charge transport layer is an electron transport layer.

[0022] Preferably, the hole transport layer comprises a nickel oxide layer and / or a self-assembled molecular layer.

[0023] Preferably, the electron transport layer includes C 60 Layers and / or BCP layers.

[0024] Preferably, the perovskite light-absorbing layer has the general chemical formula ABX3, where A is any one or a combination of at least two of formamidinium ions, methylamine ions, or cesium ions, B is lead ions and / or tin ions, and X is a halide ion. For example, it could be Cs. 0.05 FA 0.73 MA 0.22 Pb(I 0.77 Br 0.23 )3 etc.

[0025] Preferably, the method for preparing the hole transport layer includes magnetron sputtering and / or slot coating.

[0026] Preferably, the perovskite light-absorbing layer is prepared by a slit coating method.

[0027] Preferably, the method for preparing the electron transport layer includes thermal evaporation.

[0028] Preferably, a transparent electrode layer is further disposed between the second charge transport layer and the gate electrode, and the material of the transparent electrode layer includes ITO (indium tin oxide).

[0029] Preferably, the method for preparing the transparent electrode layer includes magnetron sputtering.

[0030] Preferably, the thickness of the gate electrode is 150-200nm, for example, it can be 150nm, 160nm, 170nm, 180nm, 190nm or 200nm.

[0031] Preferably, the material of the grid electrode includes any one of Ag, Cu, Al, or silver-plated copper.

[0032] Preferably, the method for preparing the grid line electrode includes screen printing.

[0033] Preferably, the cooling capacity of the water-cooled stage is 6-12.56kW, for example, it can be 6kW, 6.8kW, 8kW, 9kW, 10kW, 11.3kW or 12.56kW, etc.

[0034] It should be noted that cooling capacity is the core indicator for measuring the cooling ability of a water-cooled stage. It represents the amount of heat that the water-cooled stage can absorb and transfer from the object being cooled per unit time.

[0035] In this invention, the appropriate cooling capacity of the water-cooling stage helps to achieve heat transfer during the annealing process, ensuring that the solar cells are not damaged by heat.

[0036] Preferably, the water circulation flow rate of the water-cooled platform is 8-10 L / min, for example, it can be 8 L / min, 9 L / min or 10 L / min, etc.

[0037] In this invention, sufficient water flow ensures that heat is carried away in time. If the water flow is too small, the water temperature will rise rapidly after absorbing heat, thereby reducing the cooling effect.

[0038] Preferably, the working pressure of the water-cooled stage is 0.4-0.6 MPa, for example, it can be 0.4 MPa, 0.5 MPa or 0.6 MPa.

[0039] It should be noted that the working pressure of a water-cooled platform refers to the pressure exerted on the internal cooling medium (usually water or coolant) during the operation of the water-cooling system.

[0040] In this invention, a suitable operating pressure ensures the normal circulation of the cooling medium within the system, thereby effectively transferring heat from the cooled equipment to the heat dissipation components. Excessive operating pressure may lead to safety hazards such as pipe rupture or loose connections; conversely, insufficient operating pressure may prevent the cooling medium from circulating smoothly, affecting the cooling effect.

[0041] Preferably, the laser is any one of an excimer laser, a solid-state laser, or a semiconductor laser.

[0042] Preferably, the wavelength of the laser is 400-700nm, for example, it can be 400nm, 500nm, 600nm or 700nm, and is preferably 500-600nm.

[0043] In this invention, a suitable laser wavelength helps to provide sufficient energy to achieve effective local heating while avoiding unnecessary thermal damage to the material.

[0044] Preferably, the power of the laser is 700-1000mW, for example, it can be 700mW, 800mW, 900mW or 1000mW, etc., and preferably 800-900mW.

[0045] In this invention, appropriate laser power helps to achieve efficient laser annealing of screen-printed grid electrodes, thereby improving the photoelectric conversion efficiency and fill factor of photovoltaic cells.

[0046] Preferably, the scanning rate of the laser is 30-80 mm / s, for example, it can be 30 mm / s, 40 mm / s, 50 mm / s, 60 mm / s, 70 mm / s or 80 mm / s, etc.

[0047] In this invention, the appropriate laser scanning rate affects the interaction time between the laser and the material, which in turn affects the heating and cooling process of the material, as well as the final annealing effect.

[0048] Preferably, the annealing process is carried out in an inert atmosphere.

[0049] In this invention, an inert atmosphere helps prevent the material from reacting with oxygen or other reactive gases at high temperatures during annealing, thereby avoiding oxidation and other chemical reactions that may alter the material's properties.

[0050] Preferably, the inert atmosphere includes a nitrogen atmosphere.

[0051] Preferably, the annealing time is 2.6-7s, for example, it can be 2.6s, 3s, 3.5s, 4.2s, 5.25s or 7s.

[0052] It should be noted that the annealing time mentioned above refers to the time required for laser scanning of the entire battery cell.

[0053] Preferably, the laser annealing method includes the following steps:

[0054] A perovskite-crystalline silicon tandem solar cell is provided, and then the perovskite-crystalline silicon tandem solar cell is placed on a water-cooled platform, such that the bottom of the crystalline silicon bottom cell is in contact with the water-cooled platform, and the top grid line electrode of the perovskite top cell is away from the water-cooled platform.

[0055] The perovskite top cell, along the direction away from the crystalline silicon bottom cell, includes a first charge transport layer, a perovskite light-absorbing layer, a second charge transport layer, and a grid electrode stacked together; the thickness of the grid electrode is 150-200 nm; the material of the grid electrode includes any one of Ag, Cu, Al, or silver-clad copper; the cooling capacity of the water-cooling stage is 6-12.56 kW; the water circulation flow rate of the water-cooling stage is 8-10 L / min; and the operating pressure of the water-cooling stage is 0.4-0.6 MPa.

[0056] A laser source is placed directly above the gate electrode, and the laser is emitted to anneal the gate electrode.

[0057] Wherein, the laser is any one of excimer laser, solid-state laser or semiconductor laser; the wavelength of the laser is 400-700nm; the power of the laser is 700-1000mW; the scanning rate of the laser is 30-80mm / s; the annealing treatment is carried out in an inert atmosphere; the annealing treatment time is 2.6-7s.

[0058] Secondly, the present invention provides an application of the laser annealing method as described in the first aspect in the photovoltaic field.

[0059] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0060] Compared with the prior art, the present invention has the following beneficial effects:

[0061] (1) The present invention designs an annealing method that combines laser annealing and battery water cooling. This method is not only environmentally friendly, but also reduces annealing energy consumption, reduces annealing time, significantly improves battery production efficiency, and is conducive to the large-area preparation of batteries.

[0062] (2) This method can improve the conductivity of the grid line electrode and reduce the thermal damage to each functional layer in the solar cell during the annealing process while ensuring high-quality grid line electrodes.

[0063] (3) This method helps to form more uniform and dense grid electrodes, reduce resistance, improve the interface quality between grid electrodes and various functional layers, and improve the long-term stability and reliability of solar cells.

[0064] (4) The laser annealing time for the grid line electrodes achieved by this invention is typically in the range of microseconds to milliseconds. Such a fast annealing time can significantly improve the production efficiency of the battery and is very suitable for large-area battery fabrication. Furthermore, the rapid heating of laser annealing helps to form a more uniform and dense metal layer, reducing resistance. Laser annealing can also improve the interface quality between the grid line and the perovskite layer, thereby improving the long-term stability and reliability of the battery. Attached Figure Description

[0065] Figure 1 This is a schematic diagram of the structure of a perovskite-crystalline silicon tandem solar cell provided in Embodiment 1 of the present invention.

[0066] Figure 2 This is a schematic diagram of the apparatus used in the laser annealing process provided in Embodiment 1 of the present invention.

[0067] 1-Perovskite-crystalline silicon tandem solar cell; 2-Laser source; 3-Cold water stage; 10-Back conductive metal electrode; 11-Back transparent conductive layer; 12-P-type amorphous silicon layer; 13-First intrinsic amorphous silicon layer; 14-Silicon wafer; 15-Second intrinsic amorphous silicon layer; 16-N-type amorphous silicon layer; 17-Tunneling composite layer; 18-Nickel oxide layer; 19-Self-assembled monolayer; 20-Perovskite light-absorbing layer; 21-Electron transport layer; 22-Transparent electrode layer; 23-Grid electrode. Detailed Implementation

[0068] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0069] Example 1

[0070] This embodiment provides a laser annealing method for solar cell grid lines, the laser annealing method comprising the following steps:

[0071] (1) A perovskite-crystalline silicon tandem solar cell was fabricated, and its structural schematic diagram is shown below. Figure 1 As shown, the specific steps include:

[0072] (a) Using a semi-finished heterojunction cell as a substrate, the semi-finished heterojunction cell includes a back conductive metal electrode 10, a back transparent conductive layer 11, a p-type amorphous silicon layer 12, a first intrinsic amorphous silicon layer 13, a silicon wafer 14, a second intrinsic amorphous silicon layer 15, and an n-type amorphous silicon layer 16 stacked together, and a 100 nm thick ITO layer is magnetron sputtered on the n-type amorphous silicon layer 16 as a tunneling composite layer 17.

[0073] The material of the back conductive metal electrode 10 is Ag, and the material of the back transparent conductive layer 11 is ITO.

[0074] (b) A nickel oxide layer with a thickness of 15 nm was deposited on the ITO layer by magnetron sputtering. Specific process parameters include:

[0075] High-purity (purity > 99.99%) NiOx was used as the target material, and the vacuum degree in the reaction chamber was 6 × 10⁻⁶. -4 The sputtering pressure is 0.5 Pa, the sputtering power is 1.8 kW, and the argon gas source is 0.5 Pa.

[0076] (c) A self-assembled monolayer 19 of Meo-2pacz material is coated on the nickel oxide layer 18 using a slit coating method. Specific process parameters include:

[0077] The slit coating speed is 25 mm / s, the liquid output from the coating head is 50 μL / s, the coating head height is 10 μm, the hot air annealing temperature is 100℃, and the air pressure at the air knife nozzle is 0.1 MPa.

[0078] (d) A layer with a band gap of 1.68 wV and chemical formula Cs was prepared on self-assembled monolayer 19 using the slit coating method. 0.05 FA 0.73 MA 0.22 Pb(I 0.77 Br 0.23 The perovskite light-absorbing layer 20 of 3 has the following specific process parameters:

[0079] The slit coating speed is 25 mm / s, the liquid output from the coating head is 100 μL / s, the antisolvent EA gas is blown out together with the hot air, the hot air annealing temperature is 100℃, the air pressure at the cutting edge of the knives is 0.1 MPa, and the coating head height is 10 μm.

[0080] (e) Using a high-vacuum thermal evaporation deposition method, 20 nm C layers are sequentially deposited on the perovskite light-absorbing layer 20. 60 The 8nm BCP layer and the 8nm layer serve as the electron transport layer 21, with the evaporation rate controlled at 0.05nm / s.

[0081] (f) A 100 nm thick ITO layer is sputtered onto the BCP layer using magnetron sputtering as a transparent conductive layer 22.

[0082] (g) A silver gate line with a thickness of 180 nm is deposited on the transparent conductive layer 22 by screen printing as a gate electrode 23.

[0083] (2) Figure 2 As shown, the perovskite-crystalline silicon tandem solar cell 1 prepared in step (1) is placed on a water-cooled stage 3, so that the bottom back conductive metal electrode of the crystalline silicon bottom cell is in contact with the water-cooled stage, and the top grid line electrode of the perovskite top cell is away from the water-cooled stage.

[0084] The water-cooled platform 3 has a cooling capacity of 9kW, a water circulation flow rate of 9L / min, and a working pressure of 0.5MPa.

[0085] The laser source 2 is placed directly above the gate electrode, and the laser is emitted to anneal the gate electrode.

[0086] The laser is an excimer laser with a wavelength of 500 nm, a power of 800 mW, a scanning area of ​​210 × 210 mm, a scanning rate of 50 mm / s, and the annealing process is carried out in a nitrogen atmosphere for 4.2 s (the time required for laser scanning of the entire cell).

[0087] Example 2

[0088] The only difference between this embodiment and Embodiment 1 is that the wavelength of the laser is 400nm.

[0089] Example 3

[0090] The only difference between this embodiment and Embodiment 1 is that the wavelength of the laser is 600nm.

[0091] Example 4

[0092] The only difference between this embodiment and Embodiment 1 is that the wavelength of the laser is 700nm.

[0093] Example 5

[0094] The only difference between this embodiment and Embodiment 1 is that the power of the laser is 700mW.

[0095] Example 6

[0096] The only difference between this embodiment and Embodiment 1 is that the power of the laser is 900mW.

[0097] Example 7

[0098] The only difference between this embodiment and Embodiment 1 is that the power of the laser is 1000mW.

[0099] Example 8

[0100] The only difference between this embodiment and Embodiment 1 is that the cooling capacity of the water-cooled platform is 6.8kW.

[0101] Example 9

[0102] The only difference between this embodiment and Embodiment 1 is that the cooling capacity of the water-cooled platform is 11.3kW.

[0103] Example 10

[0104] The only difference between this embodiment and Embodiment 1 is that the water circulation flow rate of the water-cooled platform is 8L / min.

[0105] Example 11

[0106] The only difference between this embodiment and Embodiment 1 is that the water circulation flow rate of the water-cooled platform is 10L / min.

[0107] Example 12

[0108] The only difference between this embodiment and Embodiment 1 is that the wavelength of the laser is 300nm.

[0109] Example 13

[0110] The only difference between this embodiment and Embodiment 1 is that the wavelength of the laser is 800nm.

[0111] Example 14

[0112] The only difference between this embodiment and Embodiment 1 is that the power of the laser is 600mW.

[0113] Example 15

[0114] The only difference between this embodiment and Embodiment 1 is that the power of the laser is 1100mW.

[0115] Example 16

[0116] The only difference between this embodiment and Embodiment 1 is that the annealing process is carried out in an oxygen-containing atmosphere.

[0117] Comparative Example 1

[0118] The only difference between this comparative example and Example 1 is that step (2) is omitted. Instead, the perovskite-crystalline silicon tandem solar cell obtained in step (1) is annealed by sintering for 6 minutes and 30 seconds at a temperature of 200°C.

[0119] Comparative Example 2

[0120] The only difference between this comparative example and Example 1 is that a water-cooled stage is not added in step (2), that is, only laser is used to anneal the top grid line electrode.

[0121] Performance testing

[0122] 1. Photoelectric performance tests were conducted on the perovskite-crystalline silicon tandem solar cells after annealing the top grid line electrodes in the above embodiments and comparative examples.

[0123] Test conditions: AM1.5, 1000W / m 2 , 25±2℃.

[0124] The test results are shown in Table 1.

[0125] Table 1

[0126]

[0127]

[0128] 2. The resistivity of the perovskite-crystalline silicon tandem solar cells after annealing the top grid line electrodes in Examples 1, 16 and Comparative Examples 1-2 was tested.

[0129] The test results are shown in Table 2.

[0130] Table 2

[0131]

[0132] analyze:

[0133] As shown in Tables 1 and 2, this invention designs an annealing method combining laser annealing and battery water cooling. This method not only reduces annealing energy consumption and annealing time, but also improves the conductivity of the grid electrodes, ensuring high-quality grid electrodes while minimizing thermal damage to the functional layers of the solar cell during the annealing process. Furthermore, this method can improve the interface quality between the grid electrodes and the functional layers, thereby enhancing the efficiency, long-term stability, and reliability of the solar cell.

[0134] As can be seen from Examples 1 and 12-13, if the wavelength of the laser is too short, it will cause the annealing area to heat up rapidly, thereby increasing the risk of thermal damage; if the wavelength of the laser is too long, the laser may penetrate deeper into the material, which may lead to an increase in the heat-affected zone, thereby increasing the risk of thermal damage.

[0135] As can be seen from Examples 1 and 14-15, if the laser power is too low, the laser will not be able to effectively penetrate the material, thus failing to achieve the expected annealing effect, and the resistivity of the silver grid line may not be reduced to the ideal level; if the laser power is too high, the excessive laser power may cause the material to overheat, thereby causing the silver grid line to melt or be damaged, affecting the shape and performance of the grid line. In addition, high-power laser may also cause spatter on the surface of the material, resulting in the grid line becoming wider and affecting the photoelectric conversion efficiency of the solar cell.

[0136] As can be seen from Examples 1 and 16, if the annealing process is carried out in an oxygen-containing atmosphere, the voltage, fill factor and efficiency of the battery will decrease. This indicates that in an oxygen-containing atmosphere, some of the grid electrodes will be oxidized, thereby reducing the conductivity of the electrodes and increasing the contact resistance.

[0137] As shown in Example 1 and Comparative Example 1, the laser energy promotes the rearrangement of metal atoms, forming a denser crystal structure, reducing lattice defects and scattering centers, thereby lowering resistivity. Furthermore, laser annealing improves the contact performance between the grid electrode and the perovskite layer, while also reducing thermal damage caused by sintering, thus reducing contact resistance and improving the fill factor and overall efficiency of the battery. In contrast, sintering involves heating the entire battery over a long period, which affects the perovskite layer, causing thermal damage and leading to reduced battery efficiency.

[0138] As can be seen from Example 1 and Comparative Example 2, the addition of a water-cooling stage can more effectively control the temperature during the laser annealing process, reduce the thermal impact of annealing on other functional layers of the solar cell, and thus further reduce the risk of thermal damage.

[0139] The applicant declares that the present invention is illustrated by the above embodiments, but the present invention is not limited to the above process steps, that is, it does not mean that the present invention must rely on the above process steps to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials used in the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A laser annealing method for solar cell grid lines, characterized in that, The laser annealing method includes the following steps: A solar cell is placed on a water-cooled platform, and the surface of the solar cell away from the water-cooled platform has grid line electrodes. The grid line electrodes are annealed using a laser.

2. The laser annealing method according to claim 1, characterized in that, The solar cell includes a perovskite-crystalline silicon tandem solar cell; Preferably, the perovskite-crystalline silicon tandem solar cell includes a crystalline silicon bottom cell, a tunneling composite layer, and a perovskite top cell stacked together. Preferably, the perovskite top cell includes a first charge transport layer, a perovskite light-absorbing layer, a second charge transport layer, and a grid electrode stacked together along the direction away from the tunneling composite layer.

3. The laser annealing method according to claim 1 or 2, characterized in that, The thickness of the gate electrode is 150-200 nm; Preferably, the material of the grid line electrode includes any one of Ag, Cu, Al, or silver-plated copper; Preferably, the method for preparing the grid line electrode includes screen printing.

4. The laser annealing method according to any one of claims 1-3, characterized in that, The cooling capacity of the water-cooled platform is 6-12.56kW; Preferably, the water circulation flow rate of the water-cooled platform is 8-10 L / min; Preferably, the working pressure of the water-cooled stage is 0.4-0.6 MPa.

5. The laser annealing method according to any one of claims 1-4, characterized in that, The laser is any one of an excimer laser, a solid-state laser, or a semiconductor laser; Preferably, the wavelength of the laser is 400-700nm, and more preferably 500-600nm.

6. The laser annealing method according to any one of claims 1-5, characterized in that, The power of the laser is 700-1000mW, preferably 800-900mW; Preferably, the scanning rate of the laser is 30-80 mm / s.

7. The laser annealing method according to any one of claims 1-6, characterized in that, The annealing process is performed in an inert atmosphere; Preferably, the inert atmosphere includes a nitrogen atmosphere.

8. The laser annealing method according to any one of claims 1-7, characterized in that, The annealing process takes 2.6-7 seconds.

9. The laser annealing method according to any one of claims 1-8, characterized in that, The laser annealing method includes the following steps: A perovskite-crystalline silicon tandem solar cell is provided, and then the perovskite-crystalline silicon tandem solar cell is placed on a water-cooled platform, such that the bottom of the crystalline silicon bottom cell is in contact with the water-cooled platform, and the top grid line electrode of the perovskite top cell is away from the water-cooled platform. The perovskite top cell, along the direction away from the crystalline silicon bottom cell, comprises a first charge transport layer, a perovskite light-absorbing layer, a second charge transport layer, and a grid electrode stacked together; the thickness of the grid electrode is 150-200 nm; the material of the grid electrode includes any one of Ag, Cu, Al, or silver-clad copper; the cooling capacity of the water-cooling stage is 6-12.56 kW; the water circulation flow rate of the water-cooling stage is 8-10 L / min; and the operating pressure of the water-cooling stage is 0.4-0.6 MPa. A laser source is placed directly above the gate electrode, and the laser is emitted to anneal the gate electrode. Wherein, the laser is any one of excimer laser, solid-state laser or semiconductor laser; the wavelength of the laser is 400-700nm; the power of the laser is 700-1000mW; the scanning rate of the laser is 30-80mm / s; the annealing treatment is carried out in an inert atmosphere; the annealing treatment time is 2.6-7s.

10. The application of the laser annealing method as described in any one of claims 1-9 in the photovoltaic field.

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