CN114864707A - Photovoltaic cell and preparation method thereof - Google Patents
Photovoltaic cell and preparation method thereof Download PDFInfo
- Publication number
- CN114864707A CN114864707A CN202210533447.XA CN202210533447A CN114864707A CN 114864707 A CN114864707 A CN 114864707A CN 202210533447 A CN202210533447 A CN 202210533447A CN 114864707 A CN114864707 A CN 114864707A
- Authority
- CN
- China
- Prior art keywords
- layer
- silver
- copper
- slurry
- shell
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000002360 preparation method Methods 0.000 title claims abstract description 10
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims abstract description 104
- 229910052709 silver Inorganic materials 0.000 claims abstract description 104
- 239000004332 silver Substances 0.000 claims abstract description 104
- NEIHULKJZQTQKJ-UHFFFAOYSA-N [Cu].[Ag] Chemical compound [Cu].[Ag] NEIHULKJZQTQKJ-UHFFFAOYSA-N 0.000 claims abstract description 92
- 239000002002 slurry Substances 0.000 claims abstract description 86
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 55
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 55
- 239000010703 silicon Substances 0.000 claims abstract description 55
- 238000007639 printing Methods 0.000 claims description 43
- 238000000034 method Methods 0.000 claims description 18
- 238000004519 manufacturing process Methods 0.000 claims description 12
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 abstract description 8
- 229910052802 copper Inorganic materials 0.000 abstract description 8
- 239000010949 copper Substances 0.000 abstract description 8
- 230000003647 oxidation Effects 0.000 abstract description 6
- 238000007254 oxidation reaction Methods 0.000 abstract description 6
- 238000003466 welding Methods 0.000 abstract description 2
- 230000000694 effects Effects 0.000 description 6
- 238000010521 absorption reaction Methods 0.000 description 4
- 238000001035 drying Methods 0.000 description 4
- 230000000903 blocking effect Effects 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 238000007650 screen-printing Methods 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- 101001073212 Arabidopsis thaliana Peroxidase 33 Proteins 0.000 description 2
- 101001123325 Homo sapiens Peroxisome proliferator-activated receptor gamma coactivator 1-beta Proteins 0.000 description 2
- 102100028961 Peroxisome proliferator-activated receptor gamma coactivator 1-beta Human genes 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000003854 Surface Print Methods 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 229910021417 amorphous silicon Inorganic materials 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 230000031700 light absorption Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 238000007747 plating Methods 0.000 description 1
- 229910000679 solder Inorganic materials 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 239000010409 thin film Substances 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/02—Details
- H01L31/0224—Electrodes
- H01L31/022466—Electrodes made of transparent conductive layers, e.g. TCO, ITO layers
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/02—Details
- H01L31/0224—Electrodes
- H01L31/022408—Electrodes for devices characterised by at least one potential jump barrier or surface barrier
- H01L31/022425—Electrodes for devices characterised by at least one potential jump barrier or surface barrier for solar cells
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/18—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
- H01L31/1884—Manufacture of transparent electrodes, e.g. TCO, ITO
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
Abstract
The application relates to the technical field of photovoltaics, and relates to a photovoltaic cell and a preparation method thereof. A photovoltaic cell, comprising: silicon chip, grid line. The grid line is formed on the surface of the silicon wafer; the grid line is in a core structure coated by a shell; the core comprises a silver-copper slurry layer, and the shell is a pure silver slurry layer; the inner core is contacted with the surface of the silicon chip, and the shell is completely covered on the exposed surface of the inner core; or the shell contacts the surface of the silicon chip and is completely coated on the exposed surface of the core. According to the photovoltaic cell, the grid line is of a shell-coated core structure, the silver-copper slurry layer is used as the grid line core and is used as the main body for transmitting current of the whole grid line, so that the consumption of silver slurry is effectively reduced, the cost is reduced, and the electrical property is not influenced; the shell of the pure silver paste layer is coated outside the silver-copper paste layer, so that the direct contact resistance of the grid line and the welding strip is reduced, and the conductivity is enhanced. And the shell is wrapped by a pure silver slurry layer, so that the oxidation of copper can be reduced, and the reliability of the battery is improved.
Description
Technical Field
The application relates to the technical field of photovoltaics, in particular to a photovoltaic cell and a preparation method thereof.
Background
With the coming of energy crisis and the increasing serious environmental pollution of traditional energy sources, the development of clean and environment-friendly energy sources becomes a social urgent need, and new energy sources become one of the important scientific research fields of 21 century research, wherein photovoltaic cells are one of the important scientific research fields.
One of the technical difficulties of the photovoltaic cell is that the printing process has high requirements on the paste, the content of Ag in the paste is high, and the cost is high.
Among many photovoltaic cells, for example, heterojunction cells, the Ag content in the paste is required to be very high.
A heterojunction cell is one that requires the deposition of a transparent conductive oxide thin film (TCO); a photovoltaic cell with a metal collector is then formed on the TCO layer by screen printing techniques. The heterojunction battery has the characteristics of high conversion efficiency, good battery stability, low temperature coefficient and low manufacturing process temperature.
However, when the heterojunction cell is manufactured by the conventional process at present, more Ag needs to be doped in the paste to maintain the low resistivity of the grid line and the low contact resistance with the TCO, but the method further increases the production cost of the silver paste and also limits the mass production of the heterojunction cell.
Disclosure of Invention
An object of the embodiment of the application is to provide a photovoltaic cell and a preparation method thereof, which can reduce the usage amount of silver paste and lower the contact resistance of a grid line.
In a first aspect, the present application provides a photovoltaic cell comprising:
a silicon wafer;
the grid line is formed on the surface of the silicon wafer; the grid line is in a core structure coated by a shell; the inner core comprises a silver-copper slurry layer, and the outer shell is a pure silver slurry layer.
According to the photovoltaic cell, the grid line is of a shell-coated core structure, the silver-copper slurry layer is used as the grid line core and is used as the main body for transmitting current of the whole grid line, so that the consumption of silver slurry is effectively reduced, the cost is reduced, and the electrical property is not influenced; the shell of the pure silver paste layer is coated outside the silver-copper paste layer, so that the direct contact resistance of the grid line and the welding strip is reduced, and the conductivity is enhanced. And the shell is wrapped by a pure silver slurry layer, so that the oxidation of copper can be reduced, and the reliability of the battery is improved.
In other optional embodiments of the present application, the core contacts the surface of the silicon wafer, and the shell completely covers the exposed surface of the core; or the shell contacts the surface of the silicon wafer and covers the whole inner core.
In other optional embodiments of the present application, when the core contacts the surface of the silicon wafer, the core further includes a TCO conductive layer, and the TCO conductive layer covers the silver-copper paste layer;
optionally, the width of the TCO conductive layer is greater than the width of the silver-copper paste layer.
In other alternative embodiments of the present application, the height of the silver-copper paste layer is greater than the height of the TCO conductive layer.
In other alternative embodiments of the present application, when the housing contacts the surface of the silicon wafer, the pure silver paste layers comprise a first pure silver paste layer and a second pure silver paste layer; the first pure silver paste layer is formed on the surface of the silicon wafer, and the silver-copper paste layer is formed on the surface of the first pure silver paste layer.
Optionally, the width of the first pure silver paste layer is greater than the width of the silver-copper paste layer.
In other alternative embodiments of the present application, the height of the silver-copper paste layer is greater than the height of the pure silver paste layer.
In other alternative embodiments of the present application, the height of the silver-copper paste layer is 15 μm to 20 μm;
optionally, the width of the silver-copper slurry layer is 35 μm to 44 μm;
optionally, the height of the layer of pure silver paste is 8 μm-12 μm;
alternatively, the width of the layer of pure silver paste is 45 μm-55 μm.
In a second aspect, the present application provides a method for manufacturing a photovoltaic cell, wherein a grid line with a core structure coated with a shell is manufactured on a surface of a silicon wafer; the inner core comprises silver copper slurry; the shell is pure silver paste;
preparing the grid line comprises: printing core slurry on the surface of a silicon wafer, and after curing, printing shell slurry on the surface of the core slurry to completely coat the core slurry; or
Printing partial shell slurry on the surface of a silicon wafer, printing core slurry on the surface of partial shell slurry after curing, and printing the residual shell slurry on the surface of the core slurry after curing to completely coat the core slurry.
In other alternative embodiments of the present application, when the core contacts the surface of the silicon wafer, the method further comprises the step of printing a TCO conductive layer;
the step of printing the TCO conducting layer is after the step of printing the silver-copper paste and before the step of printing the pure silver paste; the step of printing the TCO conductive layer includes:
the TCO conducting layer is printed on the surface of the silver-copper slurry layer, and the TCO conducting layer completely covers the silver-copper slurry layer.
In other alternative embodiments of the present application, when the housing contacts the surface of the silicon wafer, a portion of the pure silver paste is printed on the surface of the silicon wafer, after curing, a portion of the pure silver paste is printed on the surface of the silicon wafer, so that the width of the pure silver paste is smaller than that of the portion of the pure silver paste, and then the remaining pure silver paste is printed to completely cover the silver-copper paste.
In other alternative embodiments of the present application, the wet weight of the silver-copper paste is greater than the wet weight of the casing paste.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.
Fig. 1 is a schematic view of a first structure of a photovoltaic cell provided in an embodiment of the present application;
fig. 2 is a schematic view of a second structure of a photovoltaic cell provided in an embodiment of the present application.
Icon: 100-a photovoltaic cell; 110-a silicon wafer; 120-a gate line; 130-silver copper slurry layer; 140-pure silver paste layer; 141-a first layer of pure silver paste; 142-a second layer of pure silver paste; 150-TCO conductive layer.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. The components of the embodiments of the present application, generally described and illustrated in the figures herein, can be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the present application, presented in the accompanying drawings, is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
In the description of the embodiments of the present application, it should be understood that the terms "upper", "left", "right", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, or orientations or positional relationships that are conventionally placed when products of the application are used, or orientations or positional relationships that are conventionally understood by those skilled in the art, and are used for convenience of description and simplification of description, but do not indicate or imply that the devices or elements that are referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and therefore, should not be considered as limiting the present application.
Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.
In the description of the embodiments of the present application, it should also be noted that the terms "disposed" and "connected" are to be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected, unless explicitly stated or limited otherwise; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.
Referring to fig. 1, some embodiments of the present application provide a photovoltaic cell 100, including: a silicon chip 110 and a gate line 120.
Further, the gate line 120 is formed on the surface of the silicon wafer 110; the gate line 120 is of a core structure covered by a shell; the core includes a silver copper paste layer 130 and the shell is a pure silver paste layer 140.
Further, in some embodiments of the present application, the core of the gate line with the core structure covered by the outer shell contacts with a surface of a silicon wafer, and the outer shell completely covers an exposed surface of the core.
Further, in some embodiments of the present application, the outer shell contacts the surface of the silicon wafer and covers the entire inner core.
In the photovoltaic cell 100 provided by the embodiment of the application, the gate line 120 is of a shell-coated core structure, and the silver-copper paste layer 130 is used as the core of the gate line and is used as the main body of the whole gate line for transmitting current, so that the consumption of silver paste is effectively reduced, the cost is reduced, and the electrical performance is not influenced; the shell of the pure silver paste layer 140 is coated outside the silver-copper paste layer 130, so that the direct contact resistance of the grid line and the solder strip is reduced, and the conductivity is enhanced. And the outermost layer is wrapped by a pure silver slurry layer, so that the oxidation of copper can be reduced, and the reliability of the battery is improved.
The silver-copper paste layer 130 may be obtained by printing and curing a silver-copper paste composite paste commonly used in the art.
In some embodiments of the present application, referring to fig. 1, in fig. 1, the entire gate line is in a core structure covered by a shell. The outermost layer of the grid lines is a layer of pure silver paste 140. And a part of the pure silver paste layer 140 is printed on the silicon wafer 110, on which is the silver-copper paste layer 130, and the pure silver paste layer 140 is wrapped on the silver-copper paste layer 130, so as to form a complete wrapping of the silver-copper paste layer 130. The grid line with the shell-coated core structure has the advantages that the core silver-copper slurry is used as a main body for transmitting current, the silver content can be effectively reduced, meanwhile, the lower contact resistance is guaranteed, a good protection effect is formed on the silver-copper slurry, and copper oxidation is avoided.
Further, in some embodiments of the present invention, the core of the gate line with the core structure covered by the outer shell contacts the surface of the silicon wafer 110, and the outer shell completely covers the exposed surface of the core.
In some embodiments of the present application, referring to fig. 2, in fig. 2, the entire gate line is in a core structure covered by a shell. A silver-copper paste layer 130 is printed on the silicon wafer 110, which contacts the surface of the silicon wafer 110 as the core of the gate lines. In fig. 2, the outermost layer of the grid lines is a layer of pure silver paste 140. The whole grid line presents a structure that silver and copper slurry is wrapped by pure silver slurry. The grid line with the shell coated core structure has the advantages that the core silver-copper slurry is used as a main body for transmitting current, the silver content can be effectively reduced, meanwhile, the lower contact resistance is guaranteed, a good protection effect is formed on the silver-copper slurry, copper oxidation is reduced, and meanwhile, the reliability of a battery can be improved.
Further, in some embodiments of the present application, referring to fig. 2, when the core contacts the silicon wafer surface, the core further comprises a TCO conductive layer 150, and the TCO conductive layer 150 is coated on the silver copper paste layer 130.
By arranging the TCO conductive layer 150 as a core of the gate line to cover the silver-copper paste layer 130, its excellent conductivity can further reduce the contact resistance.
Referring to fig. 2, in the embodiment shown in fig. 2, the entire gate line has a structure in which silver paste wraps silver-copper paste. The grid line with the shell-coated core structure has the advantages that the core silver-copper slurry is used as a main body for transmitting current, the silver content can be effectively reduced, the lower contact resistance is guaranteed, the TCO conducting layer 150 covers the silver-copper slurry layer 130, the contact resistance can be further reduced due to the excellent conductivity of the TCO conducting layer, the pure silver slurry layer of the shell has a good protection effect on the copper slurry, copper oxidation is reduced, and meanwhile, the reliability of a battery can be improved.
Further, in some embodiments of the present application, the height of silver copper paste layer 130 is greater than the height of TCO conductive layer 150.
The higher silver-copper paste layer 130 can make the bulk resistivity of the whole gate line 120 smaller, reduce the absorption and blocking of the gate line to light, and improve the transmission performance as the main body of the whole gate line 120 for transmitting current.
Further, in some embodiments of the present application, when the housing contacts the surface of the silicon wafer, the pure silver paste layer 140 includes a first pure silver paste layer 141 and a second pure silver paste layer 142; a first pure silver paste layer 141 is formed on the surface of the silicon wafer 110, and a silver-copper paste layer 130 is formed on the surface of the first pure silver paste layer 141. A second pure silver paste layer 142 is formed on the surface of the silver-copper paste layer 130.
Further, the width of the first pure silver paste layer 141 is greater than the width of the silver-copper paste layer 130.
By setting the width of the first pure silver paste layer 141 to be greater than the width of the silver-copper paste layer 130, the contact area can be increased, and the contact resistance can be reduced.
A solid layer can also be formed on the silicon wafer by providing the first pure silver paste layer 141, which facilitates the subsequent printing of other pastes thereon.
In some embodiments of the present application, the height of the silver-copper paste layer 130 is greater than the height of the pure silver paste layer 140.
Through the height that sets up silver-copper thick liquids layer 130 is greater than pure silver thick liquids layer 140 for when whole grid line used silver-copper thick liquids layer 130 as the main part, whole height is lower, can reduce grid line body resistivity, can reduce the absorption of grid line to light and block.
In some embodiments of the present application, the silver-copper paste layer has a height of 15 μm to 20 μm.
Further, in some embodiments of the present application, the height of the silver-copper paste layer is 16 μm to 19 μm. Further optionally, in some embodiments of the present application, the silver-copper paste layer has a height of 17 μm to 18 μm.
Illustratively, the height of the silver-copper paste layer is 16 μm, 17 μm, 18 μm, or 19 μm.
Further, the width of the silver-copper slurry layer is 35-44 μm; further optionally, the width of the silver-copper paste layer is 36 μm to 43 μm; further optionally, the width of the silver-copper paste layer is 37 μm-42 μm; illustratively, the width of the silver-copper paste layer is 38 μm, 39 μm, 40 μm, 41 μm, 42 μm, or 43 μm.
Further, in some embodiments of the present application, the height of the pure silver paste layer 140 is 8 μm to 12 μm. Further optionally, the height of the layer of pure silver paste 140 described above is 9 μm to 11 μm. Illustratively, the height of the above-described pure silver paste layer 140 is 9 μm, 10 μm, or 11 μm.
Note that, in some embodiments of the present application, the height of the first pure silver paste layer 141 is 8 μm to 12 μm. The height of the second pure silver paste layer 142 is also in the range of 8 μm to 12 μm. In some embodiments, the height of the first pure silver paste layer 141 may be the same as or different from the height of the second pure silver paste layer 142. For example, in some embodiments of the present application, the height of the first pure silver paste layer 141 may be 9 μm, and the height of the second pure silver paste layer 142 may be 10 μm; alternatively, in some embodiments of the present application, the height of the first pure silver paste layer 141 may be 11 μm, and the height of the second pure silver paste layer 142 may be 11 μm.
Further, in some embodiments of the present application, the width of the pure silver paste layer is 45 μm to 55 μm. Further optionally, the width of the layer of pure silver paste described above is between 46 μm and 54 μm. Illustratively, the width of the above-described layer of pure silver paste is 47 μm, 48 μm, 49 μm, 50 μm, 51 μm, 52 μm, 53 μm, or 54 μm.
Note that, in some embodiments of the present application, the width of the first pure silver paste layer 141 is 45 μm to 55 μm. The width of the second pure silver paste layer 142 is 46 μm to 54 μm. In some embodiments, the height of the first pure silver paste layer 141 may be the same as or different from the height of the second pure silver paste layer 142. For example, in some embodiments of the present application, the width of the first pure silver paste layer 141 may be 47 μm, and the width of the second pure silver paste layer 142 may be 48 μm; alternatively, in some embodiments of the present application, the width of the first pure silver paste layer 141 may be 50 μm, and the width of the second pure silver paste layer 142 may be 51 μm.
Some embodiments of the present application provide a method for manufacturing a photovoltaic cell, wherein a gate line with a core structure coated with a shell is manufactured on a surface of a silicon wafer; the inner core comprises silver copper slurry; the shell is pure silver paste.
In some embodiments of the present application, preparing the gate line includes: printing core slurry on the surface of the silicon wafer, and after curing, printing shell slurry on the surface of the core slurry to completely coat the core slurry.
In some embodiments of the present application, a portion of the shell slurry is printed on the surface of the silicon wafer, after curing, a portion of the shell slurry is printed on the surface of the shell slurry, and after curing, the remaining shell slurry is printed on the surface of the core slurry to completely cover the core slurry.
It should be noted that the preparation method of other procedures of the photovoltaic cell is the same as the conventional method in the field.
It should also be noted that the preparation method of the photovoltaic cell grid line is suitable for both the front and the back of the silicon wafer, and can be selected according to actual needs.
Further, in some embodiments of the present application, when the core contacts the surface of the silicon wafer, the method further comprises the step of printing a TCO conductive layer;
the step of printing the TCO conducting layer is after the step of printing the silver-copper paste and before the step of printing the pure silver paste; the step of printing the TCO conductive layer includes:
the TCO conducting layer is printed on the surface of the silver-copper slurry layer, and the TCO conducting layer completely covers the silver-copper slurry layer.
Further, in some embodiments of the present application, when the housing contacts the surface of the silicon wafer, a portion of the pure silver paste is printed on the surface of the silicon wafer, after curing, a portion of the pure silver paste is printed on the surface of the silicon wafer, so that the width of the pure silver paste is smaller than that of the portion of the pure silver paste, and then the remaining pure silver paste is printed to completely cover the silver-copper paste.
Further, in some embodiments of the present application, the wet weight of the silver-copper paste is greater than the wet weight of the casing paste.
In some embodiments of the present application, a method of making a photovoltaic cell comprises the steps of: loading, back electrode printing, drying, back field printing, drying, positive electrode printing (pure silver paste), drying, positive electrode printing (silver copper paste), drying, positive electrode printing (pure silver paste), curing, light injection and test sorting.
The following is an exemplary description of the positive gate line, and the same method can be used for the back gate line.
In some embodiments of the present application, fig. 1 is implemented by first printing a layer of pure Ag paste with a height of about 10um and a width of about 50um on the surface of a silicon wafer. The width is larger and the thickness is smaller than conventional. The purpose is to increase the contact area, reduce the contact resistance, have thin thickness and have little influence on light absorption. The method can be realized by adjusting parameters of the printing table top and the screen printing plate, and the layer of slurry is dried at 200 ℃ subsequently. After the first layer is dried, the pure Ag slurry after surface printing is relatively firm and not easy to deform, and is convenient for subsequent slurry to be continuously printed on the basis. The second step continues to print silver-copper slurry on the slurry formed on the first layer, through adjusting screen parameters, the effect that the width is about 40um and the height is about 20um can be realized on the grid line printed by the silver-copper slurry, the setting purpose of the height and the width of the grid line is to reduce the resistivity of the grid line body, the height of the grid line is made as small as possible, the absorption and the blocking of the grid line to light can be reduced, the silver-copper slurry is dried to form a second layer of grid line, the second layer of grid line is used as a main body of the whole grid line for transmitting current, namely a 'core' of the grid line, so that the wet weight of the second layer of grid line is required to be greater than that of the first layer and the third layer, specific wet weight data are different from the components of the slurry used, and the specific wet weight data need to be determined according to actual conditions. And thirdly, continuously printing pure Ag slurry on the silver-copper grid line formed on the second layer, wherein the third layer can not clearly limit the specific printing line width and line height, and only the effect of wrapping the silver-copper grid line on the second layer is achieved. The third layer can be cured after being printed for a period of time, so that the third layer of pure Ag paste is downwards collapsed under the action of gravity to form a complete package on the second layer of grid lines, and the specific waiting time is influenced by the paste and the screen printing plate and needs to be determined according to specific field conditions. And after the third layer is printed, carrying out high-temperature curing treatment on the integral composite grid line.
It should be noted that the size of the line width is not absolute, and since there may be variations in the screen and the slurry actually used, the size can be adjusted up and down according to the actual situation to achieve the best efficiency.
Furthermore, as for how to realize the perfect overlapping of the front and the back of the multilayer grid lines, the position of the grid lines can be positioned by adopting the method of positioning the mark points matured on the conventional PERC battery, and the condition that the grid lines printed before and after are not deviated can be basically ensured.
It should be noted that the above-mentioned preparation method is suitable for heterojunction cells, PERC, TOPCON cells, etc.
For the heterojunction cell, the reason that the cost of the silver paste is high is that the process temperature is limited by amorphous silicon, so that good ohmic contact cannot be formed between the grid line and the TCO. At present, the common method is to blend more Ag in the paste to maintain the low resistivity of the grid line and the low contact resistance with the TCO, but the method greatly increases the production cost of the silver paste and also limits the mass production of the heterojunction cell.
The preparation method is particularly suitable for reducing the usage amount of the silver paste of the heterojunction cell and keeping low contact resistance.
The following is further described for a heterojunction cell:
in some embodiments of the present application, fig. 2 is implemented as a method of fabricating a heterojunction cell, comprising: the method comprises the steps that a silver-copper slurry layer is printed on the surface of a silicon wafer, the effect that the width of a grid line is approximately 40um and the height of the grid line is approximately 20um is achieved after the silver-copper slurry layer is printed, the height and the width of the grid line are set so as to reduce the resistivity of a grid line body, the height of the grid line is reduced as much as possible, and the absorption and the blocking of the grid line to light can be reduced. The dried silver-copper slurry is used as a main body of the whole grid line for transmitting current, namely a 'core' of the grid line. And secondly, plating a TCO conductive layer on the solidified silver-copper slurry layer, wherein the height of the TCO conductive layer is less than that of the silver-copper slurry layer, generally speaking, the TCO conductive layer only covers a very thin layer on the surface of the grid line, because the thickness of the TCO is only tens of nanometers, and the height of the grid line is in a micron level. It should be noted that the TCO conductive layer may be prepared by a conventional process for preparing a TCO conductive layer. And thirdly, printing a layer of pure Ag paste on the TCO conducting layer, wherein the thickness of the pure Ag paste is smaller than the height of the silver-copper paste, and covering the silver-copper grid line.
The TCO conducting layer in the heterojunction cell has excellent conductivity, so that the contact area between the silver-copper slurry and the TCO conducting layer is relatively larger, and the contact resistance is smaller.
The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims (10)
1. A photovoltaic cell, comprising:
a silicon wafer;
the grid line is formed on the surface of the silicon wafer; the grid line is of a core structure coated by a shell; the inner core comprises a silver-copper slurry layer, and the shell is a pure silver slurry layer.
2. The photovoltaic cell of claim 1,
the inner core is contacted with the surface of the silicon chip, and the shell is completely coated on the exposed surface of the inner core; or the shell contacts the surface of the silicon wafer and covers the whole inner core.
3. The photovoltaic cell of claim 2,
when the core contacts the surface of the silicon wafer, the core further comprises a TCO conducting layer, and the TCO conducting layer covers the silver-copper slurry layer;
optionally, the width of the TCO conductive layer is greater than the width of the silver-copper paste layer;
optionally, the height of the silver-copper paste layer is greater than the height of the TCO conductive layer.
4. The photovoltaic cell of claim 1,
when the shell contacts the surface of the silicon wafer, the pure silver paste layer comprises a first pure silver paste layer and a second pure silver paste layer; the first pure silver paste layer is formed on the surface of the silicon wafer, and the silver-copper paste layer is formed on the surface of the first pure silver paste layer;
optionally, the width of the first pure silver paste layer is greater than the width of the silver-copper paste layer.
5. The photovoltaic cell of claim 4,
the height of the silver-copper slurry layer is greater than that of the pure silver slurry layer.
6. The photovoltaic cell of claim 1,
the height of the silver-copper slurry layer is 15-20 mu m;
optionally, the width of the silver-copper slurry layer is 35 μm to 44 μm;
optionally, the height of the layer of pure silver paste is 8 μm to 12 μm;
optionally, the width of the pure silver paste layer is 45 μm to 55 μm.
7. A preparation method of a photovoltaic cell is characterized in that a grid line with a shell-coated core structure is prepared on the surface of a silicon wafer; the inner core comprises silver copper slurry; the shell is pure silver paste;
preparing the grid line comprises: printing core slurry on the surface of a silicon wafer, and after curing, printing shell slurry on the surface of the core slurry to completely coat the core slurry; or
Printing partial shell slurry on the surface of a silicon wafer, printing core slurry on the surface of partial shell slurry after curing, and printing the residual shell slurry on the surface of the core slurry after curing to completely coat the core slurry.
8. The method for producing a photovoltaic cell according to claim 7,
when the core contacts the silicon wafer surface, the method further comprises the step of printing a TCO conductive layer;
the step of printing the TCO conducting layer is after the step of printing the silver-copper paste and before the step of printing the pure silver paste; the step of printing the TCO conductive layer includes:
the TCO conducting layer is printed on the surface of the silver-copper slurry layer, and the TCO conducting layer completely covers the silver-copper slurry layer.
9. The method for producing a photovoltaic cell according to claim 7,
when the shell contacts the surface of the silicon wafer, printing partial pure silver paste on the surface of the silicon wafer, after curing, printing silver-copper paste on the surface of the silicon wafer to enable the width of the silver-copper paste to be smaller than that of the partial pure silver paste, and then printing the residual pure silver paste to enable the silver-copper paste to be completely coated.
10. The method of claim 7, comprising:
the wet weight of the silver-copper paste is greater than the wet weight of the shell paste.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210533447.XA CN114864707A (en) | 2022-05-13 | 2022-05-13 | Photovoltaic cell and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210533447.XA CN114864707A (en) | 2022-05-13 | 2022-05-13 | Photovoltaic cell and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114864707A true CN114864707A (en) | 2022-08-05 |
Family
ID=82637539
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210533447.XA Pending CN114864707A (en) | 2022-05-13 | 2022-05-13 | Photovoltaic cell and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114864707A (en) |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20130125974A1 (en) * | 2010-05-14 | 2013-05-23 | Silevo, Inc. | Solar cell with metal grid fabricated by electroplating |
| CN103137791A (en) * | 2013-03-13 | 2013-06-05 | 中国科学院上海微***与信息技术研究所 | Preparing heterojunction solar cell method of combining wet process deposition with low temperature heat treatment |
| CN104952945A (en) * | 2014-03-31 | 2015-09-30 | 比亚迪股份有限公司 | Solar cell sheet and preparation method thereof and solar cell module with cell sheet |
| US20170194517A1 (en) * | 2015-12-30 | 2017-07-06 | Solarcity Corporation | System and method for tin plating metal electrodes |
| CN113571258A (en) * | 2021-08-18 | 2021-10-29 | 苏州诺菲纳米科技有限公司 | Method for replacing HJT photovoltaic low-temperature silver paste with metal composite slurry |
| CN113611778A (en) * | 2021-08-18 | 2021-11-05 | 苏州诺菲纳米科技有限公司 | Method for replacing traditional photovoltaic low-temperature silver paste with metal compound and application of metal compound |
| CN113851545A (en) * | 2021-10-29 | 2021-12-28 | 福建金石能源有限公司 | Low-consumption silver solar cell and manufacturing method thereof |
| CN114447125A (en) * | 2020-11-02 | 2022-05-06 | 苏州阿特斯阳光电力科技有限公司 | Heterojunction solar cell and manufacturing method thereof |
-
2022
- 2022-05-13 CN CN202210533447.XA patent/CN114864707A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20130125974A1 (en) * | 2010-05-14 | 2013-05-23 | Silevo, Inc. | Solar cell with metal grid fabricated by electroplating |
| CN103137791A (en) * | 2013-03-13 | 2013-06-05 | 中国科学院上海微***与信息技术研究所 | Preparing heterojunction solar cell method of combining wet process deposition with low temperature heat treatment |
| CN104952945A (en) * | 2014-03-31 | 2015-09-30 | 比亚迪股份有限公司 | Solar cell sheet and preparation method thereof and solar cell module with cell sheet |
| US20170194517A1 (en) * | 2015-12-30 | 2017-07-06 | Solarcity Corporation | System and method for tin plating metal electrodes |
| CN114447125A (en) * | 2020-11-02 | 2022-05-06 | 苏州阿特斯阳光电力科技有限公司 | Heterojunction solar cell and manufacturing method thereof |
| CN113571258A (en) * | 2021-08-18 | 2021-10-29 | 苏州诺菲纳米科技有限公司 | Method for replacing HJT photovoltaic low-temperature silver paste with metal composite slurry |
| CN113611778A (en) * | 2021-08-18 | 2021-11-05 | 苏州诺菲纳米科技有限公司 | Method for replacing traditional photovoltaic low-temperature silver paste with metal compound and application of metal compound |
| CN113851545A (en) * | 2021-10-29 | 2021-12-28 | 福建金石能源有限公司 | Low-consumption silver solar cell and manufacturing method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102403371B (en) | There is the solar cell of the metallic grid of plating | |
| TWI362759B (en) | Solar module and system composed of a solar cell with a novel rear surface structure | |
| JP3164183B2 (en) | Photovoltaic element and module | |
| US20200091362A1 (en) | Solar cell module and method for producing same | |
| CN211376648U (en) | Heterojunction solar cell structure with double-layer TCO conductive film | |
| CN204857754U (en) | Solar cell assembly | |
| CN209056507U (en) | A kind of MWT hetero-junction silicon solar cell | |
| CN113611778A (en) | Method for replacing traditional photovoltaic low-temperature silver paste with metal compound and application of metal compound | |
| US8227733B2 (en) | Combined photoelectric conversion device | |
| CN115207159A (en) | Solar cell preparation method, solar cell and cell module | |
| CN109473493A (en) | A kind of MWT hetero-junction silicon solar cell and preparation method thereof | |
| CN103201854A (en) | Device for generating photovoltaic power and method for manufacturing same | |
| CN116913987A (en) | Solar cell preparation method, solar cell and cell assembly | |
| CN114864707A (en) | Photovoltaic cell and preparation method thereof | |
| CN218677161U (en) | Battery piece with compound alloy metal grid structure | |
| CN116936676A (en) | Solar cell preparation method, solar cell and cell assembly | |
| KR20200036780A (en) | Solar cell and method for manufacturing the same | |
| US8685784B2 (en) | Conductive channel of photovoltaic panel and method for manufacturing the same | |
| CN114361297A (en) | Preparation method of solar cell | |
| CN107425083A (en) | A kind of lamination back of the body passivation solar cell and preparation method thereof | |
| CN113823745A (en) | Solar cell module, preparation method thereof and photovoltaic module | |
| CN202996849U (en) | All-aluminum back surface field crystalline silicon solar cell | |
| CN108389928A (en) | Solar cell and preparation method thereof | |
| CN219534537U (en) | Silver-coated copper paste heterojunction battery | |
| CN219979575U (en) | Silver-coated copper heterojunction battery capable of improving reliability and conversion efficiency |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |