Device for improving efficiency of solar cell through low-temperature rapid pretreatment

Abstract

The utility model discloses a device for improving solar cell efficiency through low-temperature rapid pretreatment, and belongs to the technical field of solar cells, the device comprises a device shell, a conveyor belt and an ultraviolet light-emitting device, the conveyor belt penetrates through the device shell, the ultraviolet light-emitting device is arranged in the device shell, and a TOPCon solar cell is placed on the conveyor belt. Compared with the prior art, the low-temperature rapid ultraviolet radiation pretreatment can replace a light injection annealing process, the equipment cost and the electric power cost are reduced, and the low-temperature rapid ultraviolet radiation pretreatment can break weak Si-H bonds in the battery and improve the passivation performance of the battery, so that the efficiency of the battery is improved, and the UV attenuation resistance of the TOPCon solar battery and the assembly can be improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of solar cells, and particularly relates to a device for improving the efficiency of a solar cell through low-temperature rapid pretreatment. BACKGROUND

[0002] The manufacturing of a TOPCon solar cell includes processes such as cleaning texturing, diffusion, oxidation, annealing, PE-Poly, ALD, PECVD, screen printing, etc. The conventional electrode preparation technical route of the TOPCon solar cell is screen printing + sintering + photo-injection annealing + laser-assisted sintering. The required light intensity for photo-injection annealing is 10-60 kWh / m 2 , and the temperature is above 600°C, resulting in high equipment and power costs.

[0003] The TOPCon solar cell has the advantages of high mass production efficiency (the theoretical limit efficiency is 28.7%, higher than the theoretical limit efficiency 27.5% of HJT), excellent passivation effect, compatible process with the existing production line, mature process, etc. However, the TOPCon solar cell and module are sensitive to ultraviolet-induced degradation (UVID). CONTENT OF THE INVENTION

[0004] To solve the problems in the background art, the application provides a device for improving the efficiency of a solar cell through low-temperature rapid pretreatment, to solve the problems of high power cost of the annealing process in the prior art and the sensitivity of the TOPCon solar cell and module to ultraviolet-induced degradation (UVID).

[0005] To achieve the above-mentioned purpose, the application provides the following technical solutions.

[0006] The device for improving the efficiency of a solar cell through low-temperature rapid pretreatment comprises:

[0007] A device housing, which is a box structure made of light-proof material, and two opposite sides of the device housing are each provided with a transmission through hole;

[0008] A conveyor belt, which is arranged through the device housing in sequence through the two transmission through holes, and the TOPCon solar cell is placed on the conveyor belt, and the conveyor belt is used to drive the TOPCon solar cell to pass through the device housing;

[0009] An ultraviolet light-emitting device, which is arranged on the inner top surface of the device housing, and the light-emitting end of the ultraviolet light-emitting device is arranged to point to the conveyor belt, and the light irradiation intensity of the ultraviolet light-emitting device is 100-300 W / m 2 .

[0010] Preferably, the ultraviolet light-emitting device is at least one ultraviolet lamp.

[0011] Preferably, the ultraviolet light emitted by the ultraviolet lamp includes two types of ultraviolet light: UVA and UVB, of which UVB accounts for 3-9% and has a wavelength of 280-400nm.

[0012] Compared with the prior art, the beneficial effects of this application are:

[0013] This application optimizes the screen printing process for solar cells. The device proposed in this application for improving solar cell efficiency through low-temperature rapid pretreatment can replace the light injection annealing process with low-temperature rapid ultraviolet irradiation pretreatment, thereby reducing equipment and power costs. This application breaks the weak Si-H bonds inside the cell through low-temperature rapid ultraviolet irradiation pretreatment, improves the passivation performance of the cell, thereby improving the cell efficiency, and can also improve the UV degradation resistance of TOPCon solar cells and modules. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the specific structure of the device in this application;

[0015] Figure 2 This is a graph showing the change in minority carrier lifetime of the coated blue film after low-temperature rapid ultraviolet irradiation pretreatment.

[0016] The diagram is marked as follows:

[0017] 1-Equipment housing; 2-Conveyor belt; 3-TOPCon solar cell; 4-Ultraviolet lamp; 5-Conveyor through hole. Detailed Implementation

[0018] To facilitate understanding of the technical content of this application by those skilled in the art, the following detailed description is provided in conjunction with the accompanying drawings and specific examples. It should be understood that the specific examples described herein are merely illustrative and are not intended to limit the scope of this application.

[0019] like Figure 1 As shown, a device for improving solar cell efficiency through low-temperature rapid pretreatment includes:

[0020] Device housing 1; Device housing 1 is a box structure made of opaque material, and each of the two opposite sides of device housing 1 is provided with a transmission through hole 5;

[0021] Conveyor belt 2; Conveyor belt 2 passes through two conveyor holes 5 and penetrates the device housing 1 in sequence. TOPCon solar cell 3 is placed on conveyor belt 2. Conveyor belt 2 is used to drive TOPCon solar cell 3 through device housing 1.

[0022] Ultraviolet (UV) emission device; the UV emission device is installed on the inner top surface of the device housing 1, with the emission end of the UV emission device pointing towards the conveyor belt 2, and the light irradiance of the UV emission device is 200 W / m². 2The ultraviolet light emission device consists of two ultraviolet lamps 4, and the ultraviolet light emitted by the ultraviolet lamps 4 has a wavelength of 365nm.

[0023] The method for improving solar cell efficiency using the low-temperature rapid pretreatment apparatus of this application includes the following steps:

[0024] S1: Fabrication of TOPCon solar cell 3, specifically:

[0025] S1.1: Prepare an n-type silicon substrate, texturize the silicon substrate to remove surface impurities, and form a pyramid structure;

[0026] S1.2: Boron diffusion is performed on the front side of the silicon substrate to form a boron diffusion doped layer;

[0027] S1.3: High-temperature oxidation is performed on the front side of the silicon substrate to advance the PN junction on the boron diffusion doping layer to form borosilicate glass (BSG);

[0028] S1.4: Remove the borosilicate glass (BSG) wrapped around the back of the silicon substrate and perform polishing.

[0029] S1.5: A tunneling oxide layer and a phosphorus-doped polycrystalline silicon layer are sequentially deposited on the back side of a silicon substrate using plasma-enhanced chemical vapor deposition.

[0030] S1.6: Remove the phosphosilicate glass on the front and edges of the silicon substrate using the RCA process;

[0031] S1.7: A double-layer structure of aluminum oxide and silicon nitride is then formed on both the front and back sides of the silicon substrate using atomic layer deposition and plasma-enhanced chemical vapor deposition techniques;

[0032] S1.8: Screen-printed front and back electrodes of silicon substrate, which are then sintered at high temperature.

[0033] S2: Place the TOPCon solar cell 3 on the conveyor belt 2, and the conveyor belt 2 will move the TOPCon solar cell 3 into the device housing 1;

[0034] S3: Turn on the ultraviolet light emission device to irradiate the front of the TOPCon solar cell 3 located inside the device casing 1 with ultraviolet light, and the ultraviolet light irradiation intensity is 200W / m. 2 The irradiation time was 30 seconds, and the temperature was room temperature.

[0035] S4: After the TOPCon solar cell 3, which has been irradiated by ultraviolet light, is sent out of the device housing 1 via the conveyor belt 2, laser-assisted sintering is performed. The deflection voltage during laser-assisted sintering is set to 12V, the laser power is set to 25%, and the time is 1s.

[0036] This application optimizes the screen printing process for solar cells by replacing the photo-injection annealing process with a low-temperature rapid ultraviolet irradiation pretreatment, reducing equipment and power costs. This low-temperature rapid ultraviolet irradiation pretreatment breaks the weak Si-H bonds inside the cell, improving passivation performance and thus increasing cell efficiency. Furthermore, it enhances the UV degradation resistance of TOPCon solar cells and modules. Figure 2 As shown, at 1E15cm -3 At the injection concentration, after 10s and 30s of UV irradiation, the minority carrier lifetime of the blue film increased from 1377μs to 2843 and 2893μs, respectively. This shows that the blue film pretreatment with low-temperature rapid UV irradiation after coating significantly improved the minority carrier lifetime.

Claims

1. A device for improving solar cell efficiency through low-temperature rapid pretreatment, characterized in that, include: Device housing (1); The device housing (1) is a box structure made of opaque material, and each of the two opposite sides of the device housing (1) is provided with a transmission through hole (5). Conveyor belt (2); The conveyor belt (2) passes through two conveyor holes (5) in sequence and passes through the outer shell (1) of the device. The TOPCon solar cell (3) is placed on the conveyor belt (2). The conveyor belt (2) is used to drive the TOPCon solar cell (3) through the outer shell (1). Ultraviolet light emission device; The ultraviolet light-emitting device is installed on the inner top surface of the device housing (1), with the light-emitting end of the ultraviolet light-emitting device pointing towards the conveyor belt (2), and the light irradiance of the ultraviolet light-emitting device is 100-300W / m. 2 .

2. The apparatus for improving solar cell efficiency through low-temperature rapid pretreatment according to claim 1, characterized in that, The ultraviolet light-emitting device is at least one ultraviolet lamp (4).

3. The apparatus for improving solar cell efficiency through low-temperature rapid pretreatment according to claim 2, characterized in that, The ultraviolet light emitted by the ultraviolet lamp (4) includes two types of ultraviolet light: UVA and UVB. UVB accounts for 3-9% of the total, with a wavelength of 280-400nm.

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