Preparation method of TOPCon battery assembly based on laser enhanced contact optimization

Abstract

The invention provides a preparation method of a TOPCon battery assembly based on laser enhanced contact optimization, and the method comprises the steps: designing special silver paste for the front sintering of a TOPCon battery based on the acetic acid corrosion process of a metal grid line of the TOPCon battery, and the special silver paste comprises a plurality of materials with high compactness and acetic acid corrosion resistance; sintering the special silver paste on the front surface of the TOPCon cell through a laser enhanced contact optimization LECO technology so as to generate a plurality of contact points of a silver-silicon alloy area; the single-glass packaging structure of the TOPCon battery assembly is designed according to the improvement degree of the damp and heat resistance of the TOPCon battery assembly after laser-assisted sintering. According to the method, the compactness and the corrosion resistance of the grid line of the TOPCon battery are improved, the single-glass packaged TOPCon battery assembly can be generated, and the reliability and the applicability of the TOPCon battery assembly are improved.

Description

Technical Field

[0001] The present application relates to the technical field of photovoltaic module preparation, and in particular to a method for preparing a TOPCon cell module based on laser enhanced contact optimization. Background Art

[0002] With the development of new energy technology, the penetration rate of solar cells has gradually increased under the current green and low-carbon development trend. TOPCon cells, as an important type of solar cell, have been widely used in various fields.

[0003] Among them, when preparing TOPCon battery components, since it is difficult for silver ions to be reduced and crystallized in the N-type front holes of the TOPCon battery, if pure silver paste is used in the preparation process, the pure silver paste as front silver will have sintering problems.

[0004] In the related art, since Al2O3 needs to be corroded and burned through on the front side of the battery during the preparation process, about 2% aluminum is usually added to the front silver paste to increase sinterability and improve sintering contact. However, the added aluminum in the preparation scheme of the related art will reduce the density of the TOPCon battery positive grid line, thereby reducing the corrosion resistance of the TOPCon battery, making it inconvenient to produce single-glass TOPCon battery components in practical applications. Summary of the invention

[0005] The present application aims to solve one of the technical problems in the related art at least to some extent.

[0006] To this end, the first purpose of the present application is to propose a method for preparing a TOPCon battery module based on laser enhanced contact optimization, which improves the density and corrosion resistance of the TOPCon battery grid line, can generate a single-glass packaged TOPCon battery module, and improves the reliability and applicability of the TOPCon battery module.

[0007] The second object of the present application is to propose a preparation system for TOPCon battery components based on laser enhanced contact optimization;

[0008] A third object of the present application is to provide a non-transitory computer-readable storage medium.

[0009] To achieve the above-mentioned purpose, the first aspect of the present application is to propose a method for preparing a TOPCon battery assembly based on laser enhanced contact optimization, the method comprising the following steps:

[0010] Based on the acetic acid corrosion process of the metal grid lines of TOPCon batteries, a special silver paste is designed for the front sintering of TOPCon batteries, wherein the special silver paste includes a variety of high-density and acetic acid corrosion-resistant materials;

[0011] The special silver paste is sintered on the front side of the TOPCon cell to generate multiple contact points in the silver-silicon alloy area through the laser-enhanced contact optimization LECO technology;

[0012] According to the improvement of the moisture and heat resistance of TOPCon battery modules after laser-assisted sintering, the single-glass packaging structure of TOPCon battery modules is designed.

[0013] Optionally, in one embodiment of the present application, the special silver paste designed for sintering the front side of the TOPCon battery includes: designing the ratio of the silver paste in the special silver paste so that the density of the silver metal after sintering is greater than the acetic acid corrosion threshold; adjusting the lead content of the glass material in the special silver paste, wherein the adjusted lead content can open the passivation layer on the surface of the battery; adding a plurality of metals resistant to acetic acid dissolution to the glass material; adding a dissolution protection material to the special silver paste based on the anode sacrificial protection method, wherein the dissolution protection material is used to prevent lead oxide from dissolving.

[0014] Optionally, in one embodiment of the present application, the laser enhanced contact optimization LECO technology is used to sinter the special silver paste on the front side of the TOPCon battery, including: combining the induced carriers and bias voltage formed by the local laser beam to generate a local current, and introducing the local current into a low resistance path to generate a high current density area; sintering is performed at the hot spots corresponding to the high current density area to induce mutual diffusion of silver material and silicon material; and a cooling process is performed after the heating time caused by the current ends to generate multiple contact points in the silver-silicon alloy area.

[0015] Optionally, in one embodiment of the present application, according to the degree of improvement of the moisture and heat resistance of the TOPCon battery module after laser-assisted sintering, a single-glass packaging structure of the TOPCon battery module is designed, including: performing a moisture and heat aging test on the TOPCon battery module after laser-assisted sintering to obtain the moisture and heat resistance parameters of the TOPCon battery module; controlling the density of the anti-reflection film of the TOPCon battery module by adjusting the refractive index of the anti-reflection film of the TOPCon battery module; based on the moisture and heat resistance parameters and the density of the anti-reflection film, designing a single-glass packaging system of the TOPCon battery module comprising a multi-material composite adhesive film and a water-resistant transparent backplane.

[0016] Optionally, in one embodiment of the present application, the laser enhanced contact optimization LECO technology is used to sinter the special silver paste on the front side of the TOPCon battery, and also includes: reducing the size of the metal protrusion spike during the electrode sintering process of the TOPCon battery by controlling the corrosiveness of the special silver paste to retain the corresponding passivation film; reducing the contact resistance between the gate line and the silicon substrate in the TOPCon battery.

[0017] Optionally, in one embodiment of the present application, after controlling the corrosiveness of the special silver paste, it also includes: combining the adjusted corrosiveness of the special silver paste with a laser post-processing process to separate the passivation layer corrosion step and the contact point generation step in the silver electrode sintering process of the TOPCon battery; enhancing the contact of the TOPCon battery through an effective conductive path generated by laser optimization processing; and opening up the electron transmission channel that was not connected during the sintering process through the contact enhancement effect.

[0018] Optionally, in one embodiment of the present application, the laser enhanced contact optimized LECO technology is used to sinter the special silver paste on the front side of the TOPCon battery, and also includes: injecting electricity into the sintered contact CFC area as an additional current path in the total current transmission during the LECO-based sintering process.

[0019] To achieve the above objectives, the second aspect of the present application also proposes a preparation system for TOPCon battery components based on laser enhanced contact optimization, comprising the following modules:

[0020] Design module for designing special silver paste for TOPCon battery front sintering based on acetic acid corrosion process of TOPCon battery metal grid line, wherein the special silver paste includes a variety of high-density and acetic acid corrosion-resistant materials;

[0021] A sintering module for optimizing LECO technology through laser enhanced contact, sintering the special silver paste on the front side of the TOPCon cell to generate multiple contact points in the silver-silicon alloy area;

[0022] The packaging module is used to design the single-glass packaging structure of the TOPCon battery module according to the improvement of the moisture and heat resistance of the TOPCon battery module after laser-assisted sintering.

[0023] In order to implement the above-mentioned embodiments, the third aspect of the present application also proposes a non-temporary computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the method for preparing a TOPCon battery assembly based on laser enhanced contact optimization in the above-mentioned first aspect is implemented.

[0024] The technical solution provided by the embodiment of the present application brings at least the following beneficial effects: the present application first designs a special silver paste for sintering the front of the TOPCon battery based on the acetic acid corrosion process of the metal grid line of the TOPCon battery, wherein the special silver paste includes a variety of high-density and acetic acid corrosion-resistant materials; then, through the laser enhanced contact optimization LECO technology, the special silver paste is sintered on the front of the TOPCon battery to generate multiple contact points in the silver-silicon alloy area; finally, according to the degree of improvement in the moisture and heat resistance of the TOPCon battery assembly after laser-assisted sintering, the single-glass packaging structure of the TOPCon battery assembly is designed. Thus, by introducing LECO technology at the TOPCon battery end, the present application enables the silver-aluminum paste on the front of the battery to be replaced by a special paste, thereby greatly improving the density and corrosion resistance of the battery grid line and ensuring the safety of the battery in practical applications. Moreover, for the TOPCon battery assembly, the improvement of the moisture and heat resistance obtained by laser-assisted sintering can design and prepare the single-glass packaging structure of the TOPCon battery assembly, thereby enriching the packaging structure of the TOPCon battery assembly and the applicable application scenarios, and improving the practicality and applicability of the TOPCon battery assembly. In addition, the present application also significantly improves the contact effect of the TOPCon battery through a variety of optimized LECO sintering methods, thereby enhancing the efficiency of the TOPCon battery.

[0025] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0027] Figure 1 A flow chart of a method for preparing a TOPCon battery assembly based on laser enhanced contact optimization proposed in an embodiment of the present application;

[0028] Figure 2 A flow chart of a design method for a special silver paste proposed in an embodiment of the present application;

[0029] Figure 3 A flow chart of a LECO-based sintering method proposed in an embodiment of the present application;

[0030] Figure 4 A schematic diagram of the structure of a system for preparing a TOPCon battery assembly based on laser enhanced contact optimization proposed in an embodiment of the present application. DETAILED DESCRIPTION

[0031] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0032] The following describes a method and system for preparing a TOPCon battery assembly based on laser enhanced contact optimization proposed in an embodiment of the present invention with reference to the accompanying drawings.

[0033] Figure 1 A flow chart of a method for preparing a TOPCon battery assembly based on laser enhanced contact optimization proposed in an embodiment of the present application, such as Figure 1 As shown, the method comprises the following steps:

[0034] Step S101, based on the acetic acid corrosion process of the metal grid line of the TOPCon battery, a special silver paste for sintering the front side of the TOPCon battery is designed, wherein the special silver paste includes a variety of materials with high density and resistance to acetic acid corrosion.

[0035] It should be noted that the N-type front holes of the TOPCon battery are difficult for silver ions to be reduced and crystallized, so they cannot be output. The hole filling degree is too low, and there will be sintering problems when using pure silver paste as the front silver. Since the front side needs to corrode and burn through Al2O3, about 2% of aluminum is introduced into the front silver in the related technology to increase the sinterability. However, although this method improves the contact, the appearance of aluminum reduces the density of the positive grid line and reduces the corrosion resistance.

[0036] To this end, the present application first analyzes the acetic acid corrosion process of the metal grid line of the TOPCon battery in the related art, and summarizes several main chemical reaction formulas in the corrosion process. As an example, the chemical reaction formulas of several reaction corrosion processes are included as follows:

[0037]

[0038] Based on the principle of the acetic acid corrosion process of the metal grid line represented by the above reaction formula, the present application designs a special silver paste for the front sintering of the TOPCon battery. The obtained special silver paste can avoid the above acetic acid corrosion process as much as possible by adding a variety of high-density and acetic acid corrosion-resistant materials.

[0039] In order to more clearly describe the special silver paste designed in the present application, an exemplary description is given below using a paste design method proposed in an embodiment of the present application. Figure 2 This is a flow chart of a design method for a special silver paste proposed in an embodiment of the present application, such as Figure 2 As shown, the method comprises the following steps:

[0040] Step S201, designing the proportion of the silver paste in the special silver paste so that the density of the silver metal after sintering is greater than the acetic acid corrosion threshold.

[0041] Specifically, a silver paste is first developed that can reduce holes and gaps after sintering, so that the silver metal is sufficiently dense after printing and sintering, wherein the density of the silver metal after sintering is greater than a preset acetic acid corrosion threshold. The acetic acid corrosion threshold is used to indicate whether the density of the silver metal after sintering can prevent acetic acid from entering the glass-silver-silicon interface. When the density is greater than the acetic acid corrosion threshold, the sintered silver metal can prevent acetic acid from entering the glass-silver-silicon interface.

[0042] In the specific implementation, a large number of experiments can be conducted in advance to verify that corresponding materials are added to the silver paste, and the material ratio of the silver paste and the proportion of the silver paste in the special silver paste are adjusted to obtain a ratio of silver paste in which the density of the silver metal after sintering meets the above requirements.

[0043] Step S202, adjusting the lead content of the glass material in the special silver paste, wherein the adjusted lead content can open the passivation layer on the surface of the battery.

[0044] Specifically, the content of lead (Pb) in the glass material in the special silver paste is reduced. However, this embodiment does not simply reduce the Pb content. Since this application requires the use of Pb glass to open the passivation layer on the surface of the battery, it can be verified through a large number of experiments that the lead content of the glass material is adjusted so that it can just open the passivation layer on the surface of the battery, and the excess Pb content is within the allowable smaller range.

[0045] Step S203, adding a plurality of metals resistant to dissolution by acetic acid to the glass frit.

[0046] Specifically, a metal material that is not easily dissolved by acetic acid is added to the glass material. The type and amount of the added metal material can be determined according to actual applications. For example, antimony (Sb) and bismuth (Bi) can be added.

[0047] Step S204, adding a dissolving protective material into the special silver paste based on the anode sacrificial protection method, wherein the dissolving protective material is used to prevent lead oxide from dissolving.

[0048] Specifically, by utilizing the anode sacrificial protection method, a material capable of preventing lead oxide from dissolving is added to a special silver paste. The specific type of material added can be determined according to actual needs, and the present application does not impose any restrictions on this. It is only necessary to ensure that the cost of the material is less expensive than lead oxide and that the material dissolves before lead oxide and can prevent lead oxide from dissolving.

[0049] Step S102, using laser enhanced contact optimization LECO technology, a special silver paste is sintered on the front side of the TOPCon battery to generate multiple contact points in the silver-silicon alloy area.

[0050] Among them, the main working principle of laser-enhanced contact optimization (LECO) is: through high-intensity laser irradiation of the cell to excite the charge carriers, while applying a deflection voltage of 10V or more, thereby generating a local current of several amperes, sintering occurs at the corresponding location to trigger the mutual diffusion of silver paste and silicon, which will significantly reduce the contact resistance between metal and semiconductor. Laser-assisted sintering allows a larger sintering temperature window, achieves correct contact on ultra-low doped emitters, and allows a higher voltage Voc, making laser-assisted sintering more advantageous than standard sintering.

[0051] In order to more clearly describe the detailed process of sintering based on LECO technology in the present application, a method of sintering the special silver paste obtained in the previous step on the front side of the TOPCon battery proposed in an embodiment of the present application is exemplified below. Figure 3 A flow chart of a LECO-based sintering method proposed in the embodiment of the present application, such as Figure 3 As shown, the method comprises the following steps:

[0052] Step S301 , combining the induced carriers formed by the local laser beam and the bias voltage to generate a local current, and introducing the local current into a low resistance path to generate a high current density area.

[0053] Specifically, the induced carriers are formed by the local laser beam, and then combined with the bias voltage to form a local current. Among them, the preferred path of the local current is a low-resistance path, which must already exist between the emitter and Ag under the gate line and lead to high current density. A high current density area is generated from the relevant area of ​​the path. In specific implementation, these paths can be found at or near the top of the pyramid.

[0054] Step S302 , sintering is performed at the heating point corresponding to the high current density area to induce mutual diffusion of the silver material and the silicon material.

[0055] Specifically, since high current density may cause hot spots, sintering occurs in the relevant areas of the hot spots corresponding to the high current density areas in step S301, thereby inducing mutual diffusion of silver and silicon.

[0056] Step S303, after the heating time caused by the current ends, a cooling process is performed to generate a plurality of contact points in the silver-silicon alloy region.

[0057] Specifically, after sintering, the cooling process begins. Since the heating time caused by the current is between microseconds and milliseconds, which mainly depends on the carrier lifetime, the temperature near the melting point will drop rapidly and enter the cooling process.

[0058] Based on the above LECO processing, this example also analyzes the changes in the surface of the TOPCon battery before and after the sintering process based on the LECO technology, and obtains the following condensation: The contact points formed by LECO are mostly located near the top of the pyramid. For some areas of interest 1, filamentary bright material contrast areas are found in the silicon, indicating that silver has penetrated into the silicon. For other areas of interest 2, dark areas appear in the silver grid lines, indicating that silicon is doped. The filamentary bright material in the area of ​​interest 1 comes from Ag during the rapid cooling step. x Si y Segregation of excess Ag in the phase. Current transport is based on electron tunneling through the glass layer due to Ag precipitates in the glass and dissolved Ag and Ag grains growing on the silicon surface. In addition, current injection firing of Ag paste in the boron emitter can generate additional Ag dendrites in the glass layer.

[0059] In this embodiment, during the sintering process of the special silver paste on the front side of the TOPCon cell by laser enhanced contact optimization LECO technology, it also includes: injecting electricity into the sintered contact (CFC) area as an additional current path in the total current transmission in the LECO-based sintering process. CFC can be used to create local contact points on the emitter and back passivation layer of the cell by using current to form a good contact between the metal and the semiconductor, thereby reducing the recombination loss on the cell surface and improving the photoelectric conversion efficiency of the cell.

[0060] It should be noted that laser-assisted sintering is applicable to all high-temperature sintering processes that burn through silver paste, so it can be applied to PERC, TOPCon and BC cells. Compared with PERC cells, the front of the TOPCon cell targeted by this application is mainly hole conductive. LECO excites a large number of free electrons when the reverse voltage is increased. When encountering colloidal silver with large resistance, it will generate instantaneous high temperature, causing the silver paste and silicon to form a eutectic diffusion. When the diffusion contact forms a lower resistance, the heat at the melting point disappears instantly, the temperature decreases, and the contact quality of the formed silver-silicon alloy area is higher than that of silver crystals, thereby solving the front contact of the TOPCon cell, allowing the TOPCon cell efficiency to smoothly cross the 25.5% efficiency stage, and reducing the difficulty of thinning the back of the cell poly, which is beneficial to the technical development of N-type cells.

[0061] Based on the above embodiments, in order to further improve the efficiency of N-type batteries, the present application also improves the above laser-assisted sintering technology in some embodiments.

[0062] As a first example, in some embodiments of the present application, a special silver paste is sintered on the front side of the TOPCon battery through laser enhanced contact optimization LECO technology, and the following steps are also included: by controlling the corrosiveness of the special silver paste, the size of the metal protrusion spike during the electrode sintering process of the TOPCon battery is reduced to retain the corresponding passivation film; the contact resistance between the gate line and the silicon substrate in the TOPCon battery is reduced.

[0063] Specifically, this embodiment first controls the corrosiveness of the slurry, while ensuring that the contact meets the requirements, and reduces the size of the spike during the electrode sintering process, thereby retaining more passivation film and reducing the metal area recombination. Among them, the spike is a small metal protrusion formed on the battery cell, which is used to form a local contact point on the surface of the battery cell. The spike size includes the size and shape of these metal protrusions. By reducing the size of the spike, more passivation film can be retained in the saved area.

[0064] Furthermore, by improving the parameters and operating mode of the laser-assisted sintering equipment, the contact resistance between the gate line and the silicon substrate in the TOPCon battery can be reduced, the opening voltage and short-circuit current can be increased, and the efficiency can be further improved by up to 0.3% based on the existing sintering and light injection annealing.

[0065] As a second example, in some embodiments of the present application, after controlling the corrosiveness of the special silver paste, it also includes: combining the adjusted corrosiveness of the special silver paste with the laser post-processing process to separate the passivation layer corrosion step and the contact point generation step in the silver electrode sintering process of the TOPCon battery; enhancing the contact of the TOPCon battery through an effective conductive path generated by laser optimization processing; and opening up the electron transmission channel that was not open during the sintering process through the contact enhancement effect.

[0066] Specifically, in this embodiment, the two key steps of passivation layer erosion and contact formation in the silver electrode sintering process can be separated by controlling the corrosiveness of the slurry and combining it with the laser post-processing process, thereby reducing the contact resistance while maintaining the open circuit voltage as high as possible. This embodiment successfully reduced the erosion of the passivation layer during conventional sintering. After EL testing, it was found that the conventional sintering method would display a large area of ​​black film, but the effective conductive path generated by the laser optimization treatment of this application can successfully enhance the contact of the battery. Furthermore, excellent efficiency is achieved through equipment parameter optimization. From a mechanism perspective, the formula design adjustment of this embodiment reduces the burn-through area, and through the enhancement effect, some electron transmission channels that were not connected in the previous sintering process are opened, thereby significantly improving the contact effect. In different battery structures, this embodiment can achieve an efficiency improvement of 0.1%-0.2% in conjunction with laser optimization technology.

[0067] Step S103, designing a single-glass packaging structure of the TOPCon battery assembly according to the degree of improvement of the moisture and heat resistance of the TOPCon battery assembly after laser-assisted sintering.

[0068] Specifically, for TOPCon batteries, the present application improves the corrosion resistance and application efficiency of the batteries through the above steps. In terms of further preparing TOPCon battery modules through packaging and other processes, due to the laser-assisted sintering through the above steps, the moisture and heat resistance of the TOPCon battery modules can be improved. Therefore, the present application also prepares single-glass packaged TOPCon battery modules that have not yet been popularized based on this.

[0069] Among them, the principles of the single-glass packaging structure of the TOPCon battery module that can be realized in the present application include: First, the hydrolysis resistance and acetic acid corrosion resistance of the TOPCon battery grid line are improved through the preparation process of the above embodiment, thereby improving the results of the damp heat (DH) test, and the DH test results can meet the basic requirements. Second, through further preparation improvements, the potential induced degradation (PID) of the battery module can meet the test requirements. Third, according to the improvement of the damp heat resistance performance, the water resistance of the battery module backplane can be improved through relevant improvements.

[0070] In specific implementation, in one embodiment of the present application, according to the degree of improvement of the moisture and heat resistance of the TOPCon battery module after laser-assisted sintering, a single-glass packaging structure of the TOPCon battery module is designed, including the following steps: first, a moisture and heat aging test is performed on the TOPCon battery module after laser-assisted sintering to obtain the moisture and heat resistance parameters of the TOPCon battery module; then, the density of the anti-reflection film of the TOPCon battery module is controlled by adjusting the refractive index of the anti-reflection film of the TOPCon battery module; finally, based on the moisture and heat resistance parameters and the density of the anti-reflection film, a single-glass packaging system of the TOPCon battery module including a multi-material composite adhesive film and a water-resistant transparent backplane is designed.

[0071] Specifically, in this embodiment, a damp heat aging test is first performed on the TOPCon battery assembly obtained by combining the preparation scheme in the above embodiments and related technologies to obtain the initial damp heat resistance parameters, which can indicate the degree of improvement in the damp heat resistance performance of the present application compared to conventional assemblies. Then, the density of the battery anti-reflection film is controlled by controlling the refractive index of the SiNx anti-reflection film of the battery, thereby improving the PID performance of the battery, and the density parameter of the reflective film is obtained through testing. Finally, based on the current damp heat resistance parameters and PID performance, the packaging system of the TOPCon battery assembly is designed with the goal of improving the water blocking ability of the backplane and the film and obtaining better PID performance, including the packaging materials used for the backplane and the film of the battery assembly.

[0072] For example, a film combining EPE and EVA materials and a water-resistant transparent back sheet can be used for module packaging. And after the packaging is completed, the currently packaged TOPCon battery module is re-tested for wet heat aging to ensure that its power attenuation is within 3%.

[0073] Therefore, the TOPCon battery module prepared in the embodiment of the present application effectively controls the attenuation, can withstand long-term reliability testing, and can meet the operating requirements of the TOPCon battery module with a single-glass package.

[0074] In summary, the preparation method of the TOPCon battery assembly based on laser enhanced contact optimization in the embodiment of the present application first designs a special silver paste for sintering the front of the TOPCon battery based on the acetic acid corrosion process of the metal grid line of the TOPCon battery, wherein the special silver paste includes a variety of high-density and acetic acid corrosion-resistant materials; then, the special silver paste is sintered on the front of the TOPCon battery through the laser enhanced contact optimization LECO technology to generate multiple contact points in the silver-silicon alloy area; finally, according to the degree of improvement of the moisture and heat resistance of the TOPCon battery assembly after laser-assisted sintering, the single-glass packaging structure of the TOPCon battery assembly is designed. Thus, the method introduces LECO technology at the TOPCon battery end, so that the silver-aluminum paste on the front of the battery can be replaced by a special paste, thereby greatly improving the density and corrosion resistance of the battery grid line, and ensuring the safety of the battery in practical applications. Moreover, for the TOPCon battery assembly, the improvement of the moisture and heat resistance obtained by laser-assisted sintering can design and prepare the single-glass packaging structure of the TOPCon battery assembly, thereby enriching the packaging structure of the TOPCon battery assembly and the applicable application scenarios, and improving the practicality and applicability of the TOPCon battery assembly. In addition, this method significantly improves the contact effect of TOPCon batteries through a variety of optimized LECO sintering methods, thereby enhancing the efficiency of TOPCon batteries.

[0075] In order to realize the above-mentioned embodiment, the present application also proposes a preparation system of TOPCon battery components based on laser enhanced contact optimization. Figure 4 A schematic diagram of the structure of a system for preparing a TOPCon battery assembly based on laser enhanced contact optimization proposed in an embodiment of the present application is shown in FIG. Figure 4 As shown, the system includes: a design module 100 , a sintering module 200 and a packaging module 300 .

[0076] Among them, the design module 100 is used for designing a special silver paste for sintering the front side of the TOPCon battery based on the acetic acid corrosion process of the metal grid line of the TOPCon battery, wherein the special silver paste includes a variety of high-density and acetic acid corrosion-resistant materials.

[0077] The sintering module 200 is used to optimize the LECO technology through laser enhanced contact, and a special silver paste is sintered on the front side of the TOPCon cell to generate multiple contact points of the silver silicon alloy area.

[0078] The packaging module 300 is used to design the single-glass packaging structure of the TOPCon battery assembly according to the improvement degree of the moisture and heat resistance performance of the TOPCon battery assembly after laser-assisted sintering.

[0079] Optionally, in one embodiment of the present application, the design module 100 is specifically used to: design a ratio of silver paste in a special silver paste so that the density of the silver metal after sintering is greater than the acetic acid corrosion threshold; adjust the lead content of the glass material in the special silver paste, wherein the adjusted lead content can open the passivation layer on the surface of the battery; add a variety of metals resistant to acetic acid dissolution to the glass material; add a dissolution protection material to the special silver paste based on the anode sacrificial protection method, wherein the dissolution protection material is used to prevent lead oxide from dissolving.

[0080] Optionally, in one embodiment of the present application, the sintering module 200 is specifically used to: generate a local current in combination with the induced carriers and bias voltage formed by the local laser beam, and introduce the local current into a low resistance path to generate a high current density area; perform sintering at the heating point corresponding to the high current density area to induce mutual diffusion of the silver material and the silicon material; and perform a cooling process after the heating time caused by the current ends to generate multiple contact points in the silver-silicon alloy area.

[0081] Optionally, in one embodiment of the present application, the packaging module 300 is specifically used to: perform a moisture and heat aging test on the TOPCon cell assembly after laser-assisted sintering to obtain the moisture and heat resistance parameters of the TOPCon cell assembly; control the density of the anti-reflection film of the TOPCon cell assembly by adjusting the refractive index of the anti-reflection film of the TOPCon cell assembly; based on the moisture and heat resistance parameters and the density of the anti-reflection film, design a single-glass packaging system for the TOPCon cell assembly comprising a multi-material composite adhesive film and a water-resistant transparent backplane.

[0082] Optionally, in one embodiment of the present application, the sintering module 200 is specifically used to: reduce the size of the metal protrusion spike during the electrode sintering process of the TOPCon battery by controlling the corrosiveness of the special silver paste to retain the corresponding passivation film; reduce the contact resistance between the gate line and the silicon substrate in the TOPCon battery.

[0083] Optionally, in one embodiment of the present application, the sintering module 200 is specifically used to: combine the adjusted corrosiveness of the dedicated silver paste with the laser post-processing process to separate the passivation layer corrosion step and the contact point generation step in the silver electrode sintering process of the TOPCon battery; enhance the contact of the TOPCon battery through an effective conductive path generated by laser optimization processing; and open up the electron transmission channel that was not connected during the sintering process through the contact enhancement effect.

[0084] Optionally, in one embodiment of the present application, the sintering module 200 is specifically used to inject electricity into the sintering contact CFC area as an additional current path in the total current transmission during the LECO-based sintering process.

[0085] It should be noted that the aforementioned explanation of the embodiment of the method for preparing a TOPCon battery assembly based on laser enhanced contact optimization is also applicable to the system of this embodiment and will not be repeated here.

[0086] In summary, the preparation system of the TOPCon battery assembly based on laser enhanced contact optimization in the embodiment of the present application first designs a special silver paste for sintering the front of the TOPCon battery based on the acetic acid corrosion process of the metal grid line of the TOPCon battery, wherein the special silver paste includes a variety of high-density and acetic acid corrosion-resistant materials; then, the special silver paste is sintered on the front of the TOPCon battery through the laser enhanced contact optimization LECO technology to generate multiple contact points in the silver-silicon alloy area; finally, according to the degree of improvement of the moisture and heat resistance of the TOPCon battery assembly after laser-assisted sintering, the single-glass packaging structure of the TOPCon battery assembly is designed. Thus, by introducing LECO technology at the TOPCon battery end, the system enables the silver-aluminum paste on the front of the battery to be replaced by a special paste, thereby greatly improving the density and corrosion resistance of the battery grid line and ensuring the safety of the battery in practical applications. Moreover, for the TOPCon battery assembly, the improvement of the moisture and heat resistance obtained by laser-assisted sintering can design and prepare the single-glass packaging structure of the TOPCon battery assembly, thereby enriching the packaging structure of the TOPCon battery assembly and the applicable application scenarios, and improving the practicality and applicability of the TOPCon battery assembly. In addition, the system significantly improves the contact effect of TOPCon cells through a variety of optimized LECO sintering methods, thereby enhancing the efficiency of TOPCon cells.

[0087] In order to implement the above-mentioned embodiments, the present application also proposes a non-temporary computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, it implements the method for preparing a TOPCon battery assembly based on laser enhanced contact optimization as described in any one of the above-mentioned first aspect embodiments.

[0088] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0089] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0090] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or more executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in the reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0091] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute the instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0092] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0093] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0094] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0095] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for preparing a TOPCon battery assembly based on laser enhanced contact optimization, characterized in that: The following steps are involved: Based on the acetic acid corrosion process of the metal grid lines of TOPCon batteries, a special silver paste is designed for the front sintering of TOPCon batteries, wherein the special silver paste includes a variety of high-density and acetic acid corrosion-resistant materials; The special silver paste is sintered on the front side of the TOPCon cell through the laser enhanced contact optimization LECO technology to generate multiple contact points in the silver silicon alloy area; According to the improvement of moisture and heat resistance of TOPCon battery modules after laser-assisted sintering, the single-glass packaging structure of TOPCon battery modules is designed.

2. The preparation method according to claim 1, characterized in that: The special silver paste designed for TOPCon cell front sintering includes: The proportion of the silver paste in the special silver paste is designed so that the density of the silver metal after sintering is greater than the acetic acid corrosion threshold; Adjusting the lead content of the glass material in the special silver paste, wherein the adjusted lead content can open the passivation layer on the surface of the battery; Adding a variety of metals resistant to dissolution by acetic acid to the glass frit; Based on the anode sacrificial protection method, a dissolution protection material is added to the special silver paste, wherein the dissolution protection material is used to prevent lead oxide from dissolving.

3. The preparation method according to claim 1, characterized in that: The LECO technology is optimized by laser enhanced contact, and the special silver paste is sintered on the front side of the TOPCon cell, including: Combining the induced carriers formed by the local laser beam with the bias voltage to generate a local current, and introducing the local current into a low resistance path to generate a high current density area; Sintering is performed at the heating point corresponding to the high current density area to induce mutual diffusion of the silver material and the silicon material; After the heating time caused by the current ends, a cooling process is performed to generate multiple contact points in the silver-silicon alloy area.

4. The preparation method according to claim 1, characterized in that: According to the improvement of the moisture and heat resistance of the TOPCon battery module after laser assisted sintering, the single-glass packaging structure of the TOPCon battery module is designed, including: Conduct a wet heat aging test on the TOPCon battery module after laser-assisted sintering to obtain the wet heat resistance parameters of the TOPCon battery module; By adjusting the refractive index of the anti-reflection film of the TOPCon cell module, the density of the anti-reflection film of the TOPCon cell module is controlled; Based on the moisture and heat resistance parameters and the density of the anti-reflection film, a single-glass packaging system of a TOPCon battery module including a multi-material composite adhesive film and a water-resistant transparent backplane is designed.

5. The preparation method according to claim 3, characterized in that: The LECO technology is optimized by laser enhanced contact, and the special silver paste is sintered on the front side of the TOPCon cell, and further includes: By controlling the corrosiveness of the special silver paste, the size of the metal protrusion spike during the electrode sintering process of the TOPCon battery is reduced to retain the corresponding passivation film; Reduce the contact resistance between the gate line and the silicon substrate in TOPCon cells.

6. The preparation method according to claim 5, characterized in that: After controlling the corrosiveness of the special silver paste, the method further comprises: Combining the modified aggressiveness of the special silver paste with a laser post-treatment process to separate the passivation layer erosion step and the contact point generation step during the silver electrode sintering process of the TOPCon cell; Enhanced contact of TOPCon cells through effective conductive paths generated by laser optimization processing; The contact enhancement effect opens up the electron transmission channels that were not connected during the sintering process.

7. The preparation method according to claim 1, characterized in that: The LECO technology is optimized by laser enhanced contact, and the special silver paste is sintered on the front side of the TOPCon cell, and further includes: Electricity is injected into the sintering contact CFC region as an additional current path in the overall current transport during the LECO-based sintering process.

8. A system for preparing TOPCon battery components based on laser enhanced contact optimization, characterized in that: include: Design module for designing special silver paste for TOPCon battery front sintering based on acetic acid corrosion process of TOPCon battery metal grid line, wherein the special silver paste includes a variety of high-density and acetic acid corrosion-resistant materials; A sintering module for optimizing LECO technology through laser enhanced contact, sintering the special silver paste on the front side of the TOPCon cell to generate multiple contact points in the silver-silicon alloy area; The packaging module is used to design the single-glass packaging structure of the TOPCon battery module according to the improvement of the moisture and heat resistance of the TOPCon battery module after laser-assisted sintering.

9. The preparation system according to claim 8, characterized in that: The design module is specifically used for: The proportion of the silver paste in the special silver paste is designed so that the density of the silver metal after sintering is greater than the acetic acid corrosion threshold; Adjusting the lead content of the glass material in the special silver paste, wherein the adjusted lead content can open the passivation layer on the surface of the battery; Adding a variety of metals resistant to dissolution by acetic acid to the glass frit; Based on the anode sacrificial protection method, a dissolution protection material is added to the special silver paste, wherein the dissolution protection material is used to prevent lead oxide from dissolving.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for preparing a TOPCon battery assembly based on laser enhanced contact optimization as described in any one of claims 1 to 7 is implemented.

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