Preparation method and preparation equipment of back contact type solar cell and related device
By alternately setting P and N zones on the back of the back contact solar cell, and preparing corresponding seed layers and insulating layers, combined with electroplating technology, the problems of the complexity of positive and negative electrode isolation and high preparation cost in the prior art are solved. The effect of simplifying the preparation process and reducing costs is achieved.
Patent Information
- Application Number
- CN202411726673.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-28
- Publication Date
- 2025-02-18
AI Technical Summary
The existing back contact solar cells require complex graphic design during the preparation process to achieve spatial isolation of positive and negative electrodes, which increases the difficulty and cost of preparation.
By alternately setting P and N regions on the back of the cell, the first seed layer and the second seed layer are prepared, and the insulating layer and the main gate seed layer are prepared in the main gate area, and finally the fine gate and main gate are prepared by electroplating. Space isolation between positive and negative poles.
The preparation process is simplified, the cost is reduced, and the preparation efficiency and performance of solar cells is improved.
Smart Images
Figure CN119486334A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of solar cell preparation, and in particular to a preparation method, preparation equipment and related devices for a back-contact solar cell. Background Art
[0002] A back-contact solar cell is a solar cell in which metal grid lines are arranged on the back of the cell. The front of the cell is not blocked by the metal grid lines, thereby enhancing the light absorption ability and increasing the short-circuit current of the cell.
[0003] Since the positive and negative electrodes are both arranged on the back of the cell and the positive and negative electrodes need to be connected in series, the positive and negative electrodes (or P and N regions) need to be isolated during the preparation process to reduce leakage caused by the contact between the positive and negative electrodes. The existing preparation method requires complex graphic design to achieve spatial separation of the main fine grids of the positive and negative electrodes.
[0004] It should be noted that the above content is not necessarily prior art, nor is it intended to limit the scope of patent protection of this application. Summary of the invention
[0005] The embodiments of the present application provide a method for preparing a back-contact solar cell, a preparation device and related devices to solve or alleviate one or more of the technical problems mentioned above.
[0006] As a first aspect of an embodiment of the present application, an embodiment of the present application provides a method for preparing a back-contact solar cell, comprising: Obtaining a battery cell, wherein the back side of the battery cell includes P regions and N regions arranged alternately; Preparing a first seed layer in the P region and preparing a second seed layer in the N region; The back side of the cell also includes a first main grid region and a second main grid region to be prepared as a main grid, the first main grid region and the second main grid region are alternately arranged, and the first main grid region and the second main grid region are both at an angle of 85°-95° with the P region and / or the N region; a plurality of first insulating layers crossing the first seed layer are prepared in the first main grid region, and a plurality of second insulating layers crossing the second seed layer are prepared in the second main grid region; Preparing a main gate seed layer on the first main gate region and the second main gate region, wherein the main gate seed layer is stacked on the first insulating layer or the second insulating layer; A first fine grid, a second fine grid and a main grid are electroplated on the back side of the cell, wherein the first fine grid covers the first seed layer, the second fine grid covers the second seed layer, and the main grid covers the main grid seed layer.
[0007] In one embodiment, the metal material used to prepare the first seed layer and / or the second seed layer includes one of silver, nickel and tin.
[0008] In one embodiment, preparing the first insulating layer and / or the second insulating layer includes: preparing by screen printing silicon slurry.
[0009] In one embodiment, preparing the main gate seed layer includes: preparing it by screen printing or laser transfer.
[0010] In one embodiment, the material used to prepare the main gate seed layer includes one of silver, nickel and tin.
[0011] In one embodiment, the metal material for electroplating the first fine grid, the second fine grid and the main grid includes one of silver, nickel, copper, aluminum and tin.
[0012] In one embodiment, the thickness of the first seed layer is 1 / 5-1 / 2 of the thickness of the first fine grid; the thickness of the second seed layer is 1 / 5-1 / 2 of the thickness of the second fine grid.
[0013] In one embodiment, the thickness of the main gate seed layer is 1 / 5-1 / 2 of the thickness of the main gate.
[0014] In one embodiment, the width of the first insulating layer / the second insulating layer is greater than the width of the main gate, and the ratio of the width of the first insulating layer / the second insulating layer to the width of the main gate is 1.2-1.9.
[0015] In one embodiment, the length of the first insulating layer / the second insulating layer is 2-5 times the width of the first fine gate / the second fine gate, and the length of the first insulating layer / the second insulating layer is smaller than the interval between two adjacent first fine gates / the second fine gates.
[0016] As a second aspect of the embodiment of the present application, the embodiment of the present application provides a preparation device for a back-contact solar cell, which is used to implement the preparation method of any implementation aspect of the above embodiment, and the preparation device includes: An electroplating unit, used for electroplating a first seed layer, a second seed layer, a first fine grid, a second fine grid and / or a main grid; The screen printing unit is used for printing the first insulating layer, the second insulating layer and / or the main grid seed layer; the printing unit comprises a screen printing device and a screen plate adapted to the first insulating layer, the second insulating layer and / or the main grid seed layer.
[0017] As a third aspect of the embodiments of the present application, the embodiments of the present application provide a back-contact solar cell, comprising a cell and an electrode grid structure disposed on the surface of the cell; the electrode grid structure is prepared by the preparation method of any of the above embodiments, so that the electrode grid structure comprises a first seed layer, a second seed layer, a plurality of first insulating layers crossing the first seed layer, a plurality of second insulating layers crossing the second seed layer, a main grid seed layer stacked on the plurality of first insulating layers or the plurality of second insulating layers, a first fine grid covering the first seed layer, a second fine grid covering the second seed layer, and a main grid covering the main grid seed layer. .
[0018] As a fourth aspect of the embodiments of the present application, the embodiments of the present application provide a photovoltaic component, including: the photovoltaic component includes at least the back-contact solar cell of any implementation aspect of the above embodiments.
[0019] In the embodiment of the present application, a first seed layer corresponding to the first fine grid, a second seed layer corresponding to the second fine grid, and a main grid seed layer corresponding to the main grid are first prepared to achieve spatial isolation between the positive and negative electrodes; the first fine grid, the second fine grid, and the main grid are then electroplated to allow low-cost metal materials, such as copper, to be electroplated, thereby reducing the preparation cost of solar cells. BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in the present application and should not be regarded as limiting the scope of the present application.
[0020] Figure 1 A schematic flow chart of a method for preparing a back-contact solar cell provided in an embodiment of the present application is shown.
[0021] Figure 2 A schematic diagram showing the structure of an HBC battery.
[0022] Figure 3 Show Figure 1 Schematic diagram of the structure before implementing step S220 in the preparation method.
[0023] Figure 4 Show Figure 1 Schematic diagram of the structure after completing step S220 in the preparation method.
[0024] Figure 5 A schematic transverse cross-sectional view of the cell in the first main grid region after step S230 is completed is shown.
[0025] Figure 6 A schematic cross-sectional view of the cell at the second main grid region after step S230 is completed is shown.
[0026] Figure 7 A schematic transverse cross-sectional view of the cell in the first main grid region after step S240 is completed is shown.
[0027] Figure 8 A schematic cross-sectional view of the cell in the second main grid region after step S240 is completed is shown.
[0028] Fig. 9 A schematic transverse cross-sectional view of the cell in the first main grid region after step S250 is completed is shown.
[0029] Fig.10 A schematic cross-sectional view of the cell at the second main grid region after step S250 is completed is shown.
[0030] Fig.11 A schematic diagram of the electrode grid line structure of the prepared back-contact solar cell is shown. DETAILED DESCRIPTION
[0031] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be noted that the embodiments and features in the embodiments of the present application can be combined with each other in the absence of conflict. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.
[0032] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.
[0033] In the present application, when it comes to a numerical interval (i.e., a numerical range), unless otherwise specified, the distribution of the optional numerical values in the numerical interval is considered to be continuous, and includes the two numerical endpoints (i.e., the minimum and maximum values) of the numerical interval, and each numerical value between the two numerical endpoints. Unless otherwise specified, when the numerical interval only refers to an integer in the numerical interval, including the two endpoint integers of the numerical range, and each integer between the two endpoints, is equivalent to directly listing each integer. When multiple numerical ranges are provided to describe features or characteristics, these numerical ranges can be merged. In other words, unless otherwise specified, the numerical range disclosed in the present application should be understood to include any and all sub-ranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, a percentage, a ratio, etc. "Numerical interval" allows for broadly including quantitative intervals such as percentage intervals, ratio intervals, and ratio intervals.
[0034] Hereinafter, exemplary embodiments according to the present application will be described in more detail with reference to the accompanying drawings. It should be noted that these exemplary embodiments can be implemented in many different forms and should not be construed as being limited to the embodiments described herein.
[0035] The present application provides a method for preparing a back-contact solar cell. Figure 1 The schematic diagram of the preparation method provided in the embodiment of the present application is shown. Figure 1 As shown, the preparation method comprises: S210 , obtaining a battery cell, wherein the back side of the battery cell includes P regions 110 and N regions 120 that are alternately arranged.
[0036] The cell may be a solar cell with an electrode grid line disposed on the back side, for example, it may be a PERC (Passivated Emitter and Rear Cell), a TOPCon (Tunnel Oxide Passivating Contacts) or an HJT (Heterojunction with Intrinsic Thin-film).
[0037] like Figure 2As shown, the HJT cell is improved to a back contact type to form an HBC (Heterojunction Back Contact) cell. The HBC cell includes, from top to bottom, an anti-reflection layer 140, an intrinsic amorphous silicon layer 150, a silicon substrate 100, an intrinsic amorphous silicon 160, N / P-type amorphous silicon (110, 120), TCO (Transparent Conducting Oxide) (not shown) and metal electrode grid lines (710, 720). Among them, the N-type amorphous silicon corresponds to the N region 120, and the P-type amorphous silicon corresponds to the P region 110. A negative electrode contact fine gate 720 is prepared in the N region 120, and a positive electrode contact fine gate 710 is prepared in the P region 110.
[0038] S220, such as Figure 3 and Figure 4 As shown, a first seed layer 310 is formed in the P region 110 , and a second seed layer 320 is formed in the N region 120 .
[0039] like Figure 3 As shown, before preparing the first seed layer 310 and the second seed layer 320, a dielectric layer 210 is deposited on the back side of the silicon substrate 100; and then the dielectric layer 210 above the P region 110 and the N region 120 is partially removed by laser ablation or exposure mask.
[0040] like Figure 4 As shown, step S220 includes preparing a first seed layer 310 and a second seed layer 320 at the position where the dielectric layer 210 is removed by electroplating or sputtering.
[0041] The first seed layer 310 is a part of the positive electrode contact fine gate 710 to receive positive electrode carriers from the P region 110 ; the second seed layer 320 is a part of the negative electrode contact fine gate 720 to receive negative electrode carriers from the N region 120 .
[0042] S230, such as Figure 5 and Figure 6 As shown, a plurality of first insulating layers 410 are formed across the first seed layer 310 in the first main gate region, and a plurality of second insulating layers 420 are formed across the second seed layer 320 in the second main gate region.
[0043] The first busbar region and the second busbar region are respectively the regions on the back side of the cell where the busbar 630 is to be prepared, the first busbar region and the second busbar region are alternately arranged, and both the first busbar region and the second busbar region form an angle of 85°-95° with the P region 110 and / or the N region 120. Fig.11As shown, the positive electrode main gate 810 prepared in the first main gate region is used to connect in series with the positive electrode contact fine gate 710; the negative electrode main gate 820 prepared in the second main gate region is used to connect in series with the positive electrode contact fine gate 720, thereby respectively conducting the current of the P region 110 and the N region 120.
[0044] The first main grid region and the second main grid region are alternately distributed along the longitudinal direction of the battery cell, and both the first main grid region and the second main grid region extend in the lateral direction of the battery cell. Figure 5 is the transverse cross section of the cell in the first main grid region, Figure 6 The first main grid region and the second main grid region are used to prepare the positive electrode main grid 810 and the negative electrode main grid 820 respectively. The positive electrode main grid 810 needs to be connected in series with the positive electrode contact fine grid 710, but isolated from the negative electrode contact fine grid 720, so as to guide the positive electrode carriers out and avoid short circuit.
[0045] In the embodiment of the present application, an insulating layer is prepared across the first seed layer 310 or the second seed layer 320 on the basis of the first seed layer 310 and the second seed layer 320 to achieve isolation from the main grid of the different electrode to avoid short circuit.
[0046] S240, such as Figure 7 and Figure 8 As shown, a main gate seed layer 500 is prepared on the first main gate region and the second main gate region, and the main gate seed layer 500 is stacked on the first insulating layer 410 or the second insulating layer 420 .
[0047] The main grid seed layer 500 is a part of the positive electrode main grid 630 / the negative electrode main grid 630 . The main grid seed layer 500 in the positive electrode main grid 630 is used to be connected in series with the positive electrode contact fine grid 710 , but is isolated from the negative electrode contact fine grid 720 .
[0048] S250, such as Fig. 9 and Fig.10 As shown, a first fine grid 610 , a second fine grid 620 and a main grid 630 are electroplated on the back of the cell, wherein the first fine grid 610 covers the first seed layer 310 , the second fine grid 620 covers the second seed layer 320 , and the main grid 630 covers the main grid seed layer 500 .
[0049] The electrode grid lines of the prepared back contact solar cell are as follows: Fig.11 shown.
[0050] In the embodiment of the present application, a first seed layer 310 corresponding to the first fine grid 610, a second seed layer 320 corresponding to the second fine grid 620, and a main grid seed layer 500 corresponding to the main grid 630 are first prepared to achieve spatial isolation between the positive and negative electrodes; and the first fine grid 610, the second fine grid 620, and the main grid 630 are then electroplated to allow low-cost metal materials, such as copper, to be electroplated, thereby reducing the preparation cost of solar cells.
[0051] In one embodiment, the metal material used to prepare the first seed layer 310 and / or the second seed layer 320 includes one of silver, nickel and tin. The first seed layer 310 and / or the second seed layer 320 are close to the silicon substrate 100, so the material used to prepare the first seed layer 310 and / or the second seed layer 320 needs to be one of silver, nickel and tin to have good adhesion with the silicon wafer and low contact resistance.
[0052] In one embodiment, preparing the first insulating layer 410 and / or the second insulating layer 420 includes: preparing by screen printing silicon paste.
[0053] The first insulating layer 410 and the second insulating layer 420 can be prepared simultaneously. When the positions, shapes and sizes of the first insulating layer 410 and the second insulating layer 420 are determined, screen printing can be performed using a screen plate adapted thereto, and the printed silicon paste covers the first seed layer 310 or the second seed layer 320 .
[0054] The silicon slurry for preparing the first insulating layer 410 and / or the second insulating layer 420 may include one or more of silicon nitride slurry and silicon oxynitride slurry.
[0055] In one embodiment, preparing the main gate seed layer 500 includes: preparing by screen printing or laser transfer.
[0056] Laser transfer of the main grid seed layer 500 can make the height of the produced grid lines uniform and controllable, saving slurry.
[0057] The screen printing method can use existing printing devices, such as a printing device for printing silicon paste to prepare the first insulating layer 410 and / or the second insulating layer 420, and use a screen that is compatible with the main grid seed layer 500, which can save equipment costs and reduce equipment space.
[0058] In one embodiment, the material used to prepare the main gate seed layer 500 includes one of silver, nickel and tin.
[0059] The main gate seed layer 500 needs to adhere to the silicon paste on the insulating layer, and therefore needs to be made of a metal material that can adhere well to silicon.
[0060] In one embodiment, the metal material for electroplating the first fine grid 610, the second fine grid 620 and the main grid 630 includes one of silver, nickel, copper, aluminum and tin. Copper or aluminum is preferred. The first fine grid 610, the second fine grid 620 and the main grid 630 are prepared with copper or aluminum as the material of the grid line, which can save material costs while having excellent conductivity, reduce the production cost of solar cells, and facilitate the wide application and promotion of back-contact solar cells.
[0061] In one embodiment, the thickness of the first seed layer 310 is 1 / 5 to 1 / 2 of the thickness of the first fine gate 610 ; the thickness of the second seed layer 320 is 1 / 5 to 1 / 2 of the thickness of the second fine gate 620 .
[0062] Taking the first seed layer 310 as an example, the first seed layer 310 and the first fine grid 610 together constitute the positive electrode contact fine grid 710 to realize the extraction of positive electrode carriers. When the material cost of the first fine grid 610 is lower than that of the first seed layer 310, the thinner the first seed layer 310 is, the more material cost is saved. The first seed layer 310 is adhered to the P region 110 and isolated from the negative electrode main grid 820. The thickness of the first seed layer 310 can achieve good effects on these two functions while taking into account cost savings.
[0063] The thickness of the first seed layer 310 and the thickness of the second seed layer 320 may be the same, and accordingly, the thickness of the first fine gate 610 and the second fine gate 620 may be the same.
[0064] In one embodiment, the thickness of the main gate seed layer 500 is 1 / 5-1 / 2 of the thickness of the main gate 630 .
[0065] The main grid seed layer 500 and the main grid 630 together constitute the positive / negative electrode main grid (810, 820). The thickness of the main grid seed layer 500 determines the amount of high-cost metal materials such as silver paste. The thicker the main grid seed layer 500, the higher the cost. The main grid seed layer 500 needs to contact the first seed layer 310 / the second seed layer 320 and realize the series connection of the first seed layer 310 / the second seed layer 320. Therefore, if it is too thin, it will affect the series connection effect.
[0066] In the embodiment of the present application, the thickness of the main grid seed layer 500 is limited to 1 / 5-1 / 2 of the thickness of the main grid 630, so as to save costs and ensure the series connection effect. For example, the thickness of the main grid seed layer 500 can be 1 / 5, 1 / 4, 1 / 3, 3 / 8, or 1 / 2 of the thickness of the main grid 630.
[0067] In one embodiment, the width of the first insulating layer 410 / the second insulating layer 420 is greater than the width of the main gate 630 , and the ratio of the width of the first insulating layer 410 / the second insulating layer 420 to the width of the main gate 630 is 1.2-1.9.
[0068] The width of the first insulating layer 410 / the second insulating layer 420 is greater than the width of the main gate 630 to ensure the insulation effect, so as to achieve the isolation between the main gate 630 and the fine gate of different polarity. The ratio of the width of the first insulating layer 410 / the second insulating layer 420 to the width of the main gate 630 is 1.2-1.9, which can ensure the isolation effect of the first insulating layer 410 / the second insulating layer 420. In practical applications, the width of the first insulating layer 410 / the second insulating layer 420 can be determined according to the determined width of the main gate 630.
[0069] In some examples, the width of the first insulating layer 410 / the second insulating layer 420 may be 1-2 um greater than the width of the main gate 630 to ensure that the insulating layer exceeds the edge width of the main gate 630 .
[0070] In one embodiment, the length of the first insulating layer 410 / the second insulating layer 420 is 2-5 times the width of the first fine gate 610 / the second fine gate 620 , and the length of the first insulating layer 410 / the second insulating layer 420 is smaller than the distance between two adjacent first fine gates 610 / the second fine gates 620 .
[0071] The insulating layer is arranged across the first seed layer 310 / the second seed layer 320. The length direction of the first insulating layer 410 / the second insulating layer 420 is in the same direction as the width direction of the first seed layer 310 / the second seed layer 320. Therefore, by limiting the length of the first insulating layer 410 / the second insulating layer 420 to 2-5 times the width of the first fine gate 610 / the second fine gate 620, it can be ensured that the insulating layer can cross the first seed layer 310 / the second seed layer 320 to ensure the isolation between the first seed layer 310 / the second seed layer 320 and the main gate 630.
[0072] The length of the first insulating layer 410 / the second insulating layer 420 is smaller than the distance between two adjacent first thin gates 610 / the second thin gates 620 to avoid the insulating layer spanning too long and thus spanning two first thin gates 610 / the second thin gates 620 at the same time, thereby affecting the series connection between the first thin gates 610 / the second thin gates 620 .
[0073] The present application also provides an electrode grid line preparation device for a back-contact solar cell, which is used to implement the preparation method of any of the above-mentioned embodiments. The preparation device includes: An electroplating unit, used for electroplating the first seed layer 310, the second seed layer 320, the first fine grid 610, the second fine grid 620 and / or the main grid 630; The screen printing unit is used to print the first insulating layer 410 , the second insulating layer 420 and / or the main grid seed layer 500 ; the printing unit includes a screen printing device and a screen plate adapted to the first insulating layer 410 , the second insulating layer 420 and / or the main grid seed layer 500 .
[0074] The preparation equipment may include a conveyor belt for conveying the battery cell to a plating unit for plating a first seed layer 310 and a second seed layer 320 according to the preparation process of the preparation method of any of the above-mentioned embodiments; and then conveying the battery cell to a screen printing unit for printing a first insulating layer 410, a second insulating layer 420 and / or a main grid seed layer 500; and then conveying the battery cell to a plating unit for plating a first fine grid 610, a second fine grid 620 and / or a main grid 630.
[0075] In some other examples, a laser transfer unit may be further included to prepare the main gate seed layer 500 ; a sputtering unit may be further included to sputter the first seed layer 310 and the second seed layer 320 .
[0076] An embodiment of the present application provides a back-contact solar cell, including a cell and an electrode grid line structure arranged on the surface of the cell; the electrode grid line structure is prepared by the preparation method of any implementation aspect of the above-mentioned embodiments, so that the electrode grid line structure includes a first seed layer 310, a second seed layer 320, a plurality of first insulating layers 410 crossing the first seed layer 310, a plurality of second insulating layers 420 crossing the second seed layer 320, a main grid seed layer 500 stacked on the plurality of first insulating layers 410 or the plurality of second insulating layers 420, a first fine grid 610 covering the first seed layer 310, a second fine grid 620 covering the second seed layer 320, and a main grid 630 covering the main grid seed layer 500.
[0077] An embodiment of the present application provides a photovoltaic component, including: the photovoltaic component includes at least a back-contact solar cell according to any one of the above embodiments.
[0078] The embodiment of the present application can also provide a photovoltaic system, including the photovoltaic components in any of the above embodiments. The advantages of the above photovoltaic components are also possessed by the photovoltaic system, which will not be repeated here. The above photovoltaic system has a wide range of applications, not only limited to photovoltaic power stations, such as ground power stations, rooftop power stations and water power stations, but also includes various equipment and devices that use solar energy to generate electricity, such as user solar power supplies, solar street lights, solar cars and solar buildings. Of course, it can be understood that the application scenarios of the photovoltaic system are not limited to this, that is to say, the photovoltaic system can be used in all fields where solar energy is required for power generation. Taking the photovoltaic power generation system network as an example, the photovoltaic system may include a photovoltaic array, a junction box and an inverter. The photovoltaic array may be an array combination of multiple photovoltaic components. For example, multiple photovoltaic components can form multiple photovoltaic arrays. The photovoltaic array is connected to a junction box. The junction box can converge the current generated by the photovoltaic array. The converged current flows through the inverter and is converted into the alternating current required by the mains power grid, and then connected to the mains network to realize solar power supply.
[0079] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.
[0080] For the convenience of description, the orientation or position relationship indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, vertical, horizontal" and "top, bottom" is usually based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description. Unless otherwise stated, these directional words do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present application; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Therefore, the exemplary term "above..." can include both "above..." and "below..." orientations. The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used here are interpreted accordingly.
[0081] Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0082] Unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is lower in level than the second feature.
[0083] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values of the parts and steps set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so that once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.
[0084] It should also be noted that "one embodiment", "another embodiment", "embodiment", etc. mentioned in this specification refer to the specific features, structures or characteristics described in conjunction with the embodiment included in at least one embodiment generally described in this application. The same expression appearing in multiple places in the specification does not necessarily refer to the same embodiment. Further, when describing a specific feature, structure or characteristic in conjunction with any embodiment, it is claimed that the realization of such feature, structure or characteristic in conjunction with other embodiments also falls within the scope of this application.
[0085] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.
[0086] It should also be noted that the above are only preferred embodiments of the present application, and the patent protection scope of the present application is not limited thereto. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.
Claims
1. A method for preparing a back-contact solar cell, characterized in that: include: Obtaining a battery cell, wherein the back side of the battery cell includes P regions and N regions arranged alternately; Preparing a first seed layer in the P region, and preparing a second seed layer in the N region; The back side of the cell also includes a first main grid region and a second main grid region for preparing a main grid, the first main grid region and the second main grid region are alternately arranged, and the first main grid region and the second main grid region are both at an angle of 85°-95° with the P region and / or the N region; a plurality of first insulating layers spanning the first seed layer are prepared in the first main grid region, and a plurality of second insulating layers spanning the second seed layer are prepared in the second main grid region; Preparing a main gate seed layer on the first main gate region and the second main gate region, wherein the main gate seed layer is stacked on the first insulating layer or the second insulating layer; A first fine grid, a second fine grid and a main grid are electroplated on the back side of the cell, wherein the first fine grid covers the first seed layer, the second fine grid covers the second seed layer, and the main grid covers the main grid seed layer.
2. The preparation method according to claim 1, characterized in that: The metal material used to prepare the first seed layer and / or the second seed layer includes one of silver, nickel and tin.
3. The preparation method according to claim 1, characterized in that: The preparation of the first insulating layer and / or the second insulating layer includes: preparing by screen printing silicon slurry.
4. The preparation method according to claim 1, characterized in that: The preparation of the main grid seed layer includes: preparing by screen printing or laser transfer.
5. The preparation method according to claim 1 or 4, characterized in that: The material used to prepare the main grid seed layer includes one of silver, nickel and tin.
6. The preparation method according to claim 1, characterized in that: The metal material for electroplating the first fine grid, the second fine grid and the main grid includes one of silver, nickel, copper, aluminum and tin.
7. The preparation method according to claim 1 or 4, characterized in that: The thickness of the first seed layer is 1 / 5-1 / 2 of the thickness of the first fine grid; the thickness of the second seed layer is 1 / 5-1 / 2 of the thickness of the second fine grid.
8. The preparation method according to claim 1, characterized in that: The thickness of the main grid seed layer is 1 / 5-1 / 2 of the thickness of the main grid.
9. The preparation method according to claim 1, characterized in that: The width of the first insulating layer / the second insulating layer is greater than the width of the main gate, and the ratio of the width of the first insulating layer / the second insulating layer to the width of the main gate is 1.2-1.
9.
10. The preparation method according to claim 1, characterized in that: The length of the first insulating layer / the second insulating layer is 2-5 times the width of the first fine gate / the second fine gate, and the length of the first insulating layer / the second insulating layer is smaller than the interval between two adjacent first fine gates / the second fine gates.
11. A device for preparing a back-contact solar cell, characterized in that: For implementing the preparation method according to any one of claims 1 to 10, the preparation equipment comprises: An electroplating unit, used for electroplating a first seed layer, a second seed layer, a first fine grid, a second fine grid and / or a main grid; A screen printing unit is used for printing a first insulating layer, a second insulating layer and / or a main grid seed layer; the printing unit comprises a screen printing device and a screen plate adapted to the first insulating layer, the second insulating layer and / or the main grid seed layer.
12. A back-contact solar cell, characterized in that: It comprises a battery cell and an electrode grid line structure arranged on the surface of the battery cell; the electrode grid line structure is made by the preparation method described in any one of claims 1 to 10, so that the electrode grid line structure comprises a first seed layer, a second seed layer, a plurality of first insulating layers crossing the first seed layer, a plurality of second insulating layers crossing the second seed layer, a main grid seed layer stacked on the plurality of first insulating layers or the plurality of second insulating layers, a first fine grid covering the first seed layer, a second fine grid covering the second seed layer, and a main grid covering the main grid seed layer.
13. A photovoltaic module, characterized in that: include: The photovoltaic module comprises at least the back-contact solar cell according to claim 12.