Solar cell, half solar cell and photovoltaic module
By setting grooves in the non-grid area of the solar cell and covering them with a passivation film, the problem of carrier recombination caused by the cutting surface after slicing is solved, reducing power generation loss and production costs.
Patent Information
- Application Number
- CN202423195101.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-24
- Publication Date
- 2025-11-25
- Estimated Expiration
- 2034-12-24
AI Technical Summary
In existing technologies, after solar cells are sliced, the cut surface becomes the center of carrier recombination, leading to damage to power generation.
Grooves are made at both ends of the non-grid area of the solar cell, and a passivation film is covered on the groove surface. The passivation film includes an aluminum oxide layer, a silicon oxide layer, a silicon nitride layer, a silicon oxynitride layer, etc., and is formed before or after slicing using existing coating processes.
This reduces the carrier recombination region on the segmented surface, lowers battery power generation losses, and eliminates the need for large-scale modifications to existing production lines, thus reducing equipment investment costs.
Smart Images
Figure CN223600266U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the field of solar cell manufacturing, concretely relates to solar cell piece, half piece solar cell piece and photovoltaic module. BACKGROUND
[0002] With the gradual popularization of slice battery assembly, tile technology, and piece and splicing technology, laser cutting technology has become the mainstream trend of the solar cell industry. In the assembly packaging process, it is necessary to perform slicing operation on the solar cell in advance. After the solar cell piece is sliced, the cutting surface will become the center of carrier recombination, causing damage to the solar cell power generation. SUMMARY
[0003] The solar cell piece, half piece solar cell piece and photovoltaic module provided by the present disclosure aim to solve at least one technical problem mentioned in the prior art.
[0004] To solve the above technical problems, the utility model adopts the technical scheme that:
[0005] The solar cell piece has first grid line area and second grid line area on the front and back surfaces simultaneously or only on the back surface, has non-grid line area between the first grid line area and the second grid line area, and the non-grid line area extends from one side to the other side of the solar cell piece along a first direction, both ends of the non-grid line area are provided with a slot, and the slot surface has a passivation film.
[0006] In some embodiments, the passivation film includes one or more layers of superimposed aluminum oxide layer, silicon oxide layer, silicon nitride layer, silicon oxynitride layer or aluminum nitride layer.
[0007] In some embodiments, the passivation film includes an aluminum oxide layer and a silicon nitride layer stacked in sequence; or the passivation film includes an aluminum oxide layer, a silicon nitride layer, a silicon oxynitride layer and a silicon oxide layer stacked in sequence.
[0008] In some embodiments, the slot extends from the edge of the solar cell piece along the first direction and terminates in the solar cell piece.
[0009] In some embodiments, the slot has an extension length of 1mm-10mm in the first direction, and the slot penetrates the solar cell piece in the thickness direction of the solar cell piece or has a depth less than the thickness of the solar cell piece.
[0010] The present disclosure also relates to a half piece solar cell piece, which includes a split surface, and the split surface includes a first area and a second area located at both ends of the first area.
[0011] The topography of the first area is different from the topography of the second area.
[0012] The surface of the second region is covered with a passivation film.
[0013] In some embodiments, the first region is free of the passivation film.
[0014] In some embodiments, the passivation film comprises one or more layers of an aluminum oxide layer, a silicon oxide layer, a silicon nitride layer, a silicon oxynitride layer, or an aluminum nitride layer stacked one on top of another.
[0015] In some embodiments, the passivation film comprises an aluminum oxide layer and a silicon nitride layer stacked one on top of another in that order; or, the passivation film comprises an aluminum oxide layer, a silicon nitride layer, a silicon oxynitride layer, and a silicon oxide layer stacked one on top of another in that order.
[0016] In some embodiments, the second region has a width along the thickness direction of the half solar cell that is equal to or less than the thickness of the half solar cell, the second region extends from the end of the cleaving plane along the length direction of the cleaving plane, and the length of the second region is 1 mm to 10 mm.
[0017] In some embodiments, the second region has a laser ablation topography, and the first region has a mechanical fracture topography.
[0018] The present disclosure also relates to a photovoltaic module, characterized by comprising a plurality of the half solar cell pieces as described above, and the plurality of the half solar cell pieces are connected in series to form a cell string.
[0019] Thanks to the use of the above technical solutions, the present disclosure has the following beneficial effects compared with the prior art:
[0020] (1) The solar cell piece of the present disclosure forms a slot at both ends of the non-grid line region, and a passivation film is arranged on the slot surface of the slot. After the piece is cut, the cleaving plane is not completely exposed. Compared with the prior art, the area of the carrier recombination region of the cleaving plane is reduced, and the power generation loss of the cell is reduced to a certain extent.
[0021] (2) Depositing a passivation film / anti-reflection film on the front and back surfaces of the cell piece is a necessary process in the manufacture of the cell piece. The slot of the cell piece of the present disclosure can be formed in the cell manufacturing process. In the process of depositing a passivation film / anti-reflection film on the front and back surfaces of the cell piece, the passivation film is deposited in the slot as well. In addition to adding a laser slotting device on the basis of the existing production line, no large-scale modification of the production line is required. BRIEF DESCRIPTION OF DRAWINGS
[0022] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or the prior art description. Obviously, the drawings described below are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.
[0023] Figure 1 Structure diagram of the solar cell in the embodiment 1 of the present application;
[0024] Figure 2 Structure diagram of the section of the passivation film in the embodiment 1 of the present application;
[0025] Figure 3 Structure diagram of the solar cell in the embodiment 2 of the present application;
[0026] Figure 4 Structure diagram of the solar cell in the embodiment 3 of the present application;
[0027] Figure 5 Structure diagram of the solar cell in the embodiment 4 of the present application;
[0028] Figure 6 Structure diagram of the section in the embodiment 5 of the present application;
[0029] Figure 7 Structure diagram of another section in the embodiment 5 of the present application;
[0030] Figure 8 Structure diagram of still another section in the embodiment 5 of the present application;
[0031] Figure 9 Structure diagram of yet another section in the embodiment 5 of the present application.
[0032] Explanation of the reference signs:
[0033] 1-solar cell; 2-slot; 3-passivation film; 31-aluminum oxide layer; 32-silicon oxide layer; 33-silicon nitride layer; 34-silicon oxynitride layer; 4-first region; 5-second region. Specific embodiments
[0034] In order to better understand the present disclosure, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, but not all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without creative work should fall within the scope of the present disclosure.
[0035] It should be noted that the terms "first", "second", and the like in the description and claims of the present disclosure and the above drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or a chronological sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present disclosure described herein can be implemented. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device that includes a series of steps or units does not necessarily have to include only those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to the process, method, product or device.
[0036] In the present disclosure, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal", and the like indicate the orientation or positional relationship shown in the drawings. These terms are mainly used to better describe the present disclosure and its embodiments, and are not intended to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.
[0037] In addition, in addition to indicating the orientation or positional relationship, the above-mentioned partial terms can also be used to indicate other meanings, for example, the term "upper" can also be used to indicate a certain attachment relationship or connection relationship in some cases. For those skilled in the art, the specific meaning of these terms in the present disclosure can be understood according to the specific circumstances.
[0038] In addition, the terms "mount", "set", "provided with", "connected", "connected", "sleeved" should be broadly understood. For example, it can be fixedly connected, detachably connected, or integrally constructed; it can be mechanically connected, or electrically connected; it can be directly connected, or indirectly connected through an intermediate medium, or internal communication between two devices, elements or components. For those skilled in the art, the specific meaning of the above terms in the present disclosure can be understood according to the specific circumstances.
[0039] It should be noted that the embodiments in the present disclosure and the features in the embodiments can be combined with each other without conflict. The present disclosure will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.
[0040] Embodiment 1
[0041] Please refer to Figure 1 and Figure 2 The present embodiment provides a solar cell wafer, which has a first grid line area and a second grid line area on the front surface and the back surface, such as a TOPcon cell, or only on the back surface, such as a back contact cell. The present disclosure does not make specific limitations on the type of solar cell wafer 1.
[0042] The first grid line area and the second grid line area have a non-grid line area therebetween, the non-grid line area extends from one side to the other side of the solar cell wafer 1 along the first direction, and both ends of the non-grid line area are respectively provided with a slot 2, and the slot surface of the slot 2 has a passivation film 3. The non-grid line area can have one, and one non-grid line area can divide the solar cell wafer 1 into two halves. The non-grid line area can also have multiple, and multiple non-grid line areas can divide the solar cell wafer 1 into multiple sub-pieces.
[0043] By covering the passivation film 3 on the slot surface of the slot 2, the cutting topography of the slot 2 can be effectively protected, the edge defects directly exposed to the air can be reduced, the number of dangling bonds can be reduced, and thus the formation of carrier recombination centers can be reduced, and the overall performance of the cell can be improved. The slot 2 is obtained by concentrating laser energy on a small area on the surface of the solar cell wafer 1 by laser cutting technology, so that the material in the area is sublimated and evaporated to be removed.
[0044] The slot 2 extends from the edge of the solar cell wafer 1 along the first direction and terminates in the solar cell wafer 1, and the extension length of the slot 2 in the first direction is 1mm-10mm. Specifically, the extension length of the slot 2 in the first direction can be 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, and the present disclosure does not make specific limitations thereon. In the present embodiment, the slot 2 penetrates the solar cell wafer 1 in the thickness direction of the solar cell wafer 1.
[0045] It is worth noting that the solar cell wafer 1 with the slot 2 is still a whole piece structure, which is compatible with the existing preparation process, processing equipment and tooling of the solar cell wafer 1. Therefore, the passivation film 3 on the slot surface of the slot 2 can be prepared through the film plating process in the original preparation process. Specifically, the slot 2 process should be arranged at least before the last film plating process in the preparation process. Thus, it is avoided to increase new film plating equipment, and the overall production cost is reduced.
[0046] The fabrication process of solar cell 1 includes at least one coating step among ALD deposition, positive film deposition, back film deposition, and protective film deposition. By arranging the laser cutting step before the last coating step, the passivation film 3 is formed under the action of one or more of the ALD deposition, positive film deposition, back film deposition, and protective film deposition steps.
[0047] In detail, the passivation film 3 includes one or more layers of aluminum oxide layer 31, silicon oxide layer 32, silicon nitride layer 33, silicon oxynitride layer 34, or aluminum nitride layer.
[0048] like Figure 2 As shown, in this embodiment, the passivation film 3 includes an aluminum oxide layer 31, a silicon oxide layer 32, a silicon nitride layer 33, and a silicon oxynitride layer 34 sequentially stacked on the groove surface of the self-grooving 2. This disclosure does not specifically limit the type of passivation film 3; it is determined by the types of the front film, back film, and protective film of the solar cell 1, as well as the sequence of steps in the fabrication process.
[0049] As described above, the passivation film 3 extends to at least the front or back of the solar cell 1. During the coating process, the passivation film 3 is simultaneously formed on the surface of the groove 2, seamlessly connecting with the film formed on the front or back of the solar cell 1, without creating a coating layer that affects aesthetics or performance. This not only simplifies the production process but also reduces equipment investment costs, making overall production more efficient and economical.
[0050] It is worth noting that, in order to further improve the passivation effect on the surface of the groove 2, in some preferred embodiments, the laser cutting process can be arranged before the cleaning process preceding the coating process. This allows the cleaning process to remove dust and dirt from the surface of the groove 2, and to etch the surface of the groove 2, reducing damage. Combined with the subsequent coating process, this can effectively fill and repair these damages, thereby improving the overall performance of the passivation film 3 and the photoelectric conversion efficiency of the solar cell.
[0051] Example 2
[0052] This embodiment provides a solar cell 1, which differs from the solar cell in Embodiment 1 in that the depth of the groove 2 is less than the thickness of the solar cell 1.
[0053] Detailed, such as Figure 3 As shown, the groove 2 is formed by recessing inward from the front side of the solar cell 1. The passivation film 3 is formed through one or more processes, including ALD deposition, positive film deposition, and protective film deposition.
[0054] Example 3
[0055] The embodiment provides a solar cell 1, which is different from the solar cell in the embodiment 1 in that the depth of the groove 2 is less than the thickness of the solar cell 1.
[0056] As shown in the figure, the groove 2 is formed by being recessed inward from the back of the solar cell 1. Figure 4 The passivation film 3 is formed under the action of one or more processes of ALD deposition, back plating and protective film plating.
[0057] Embodiment 4
[0058] The embodiment provides a solar cell 1, which is different from the solar cell in the embodiment 1 in that the depth of the groove 2 is less than the thickness of the solar cell 1.
[0059] As shown in the figure, the groove 2 is formed by being recessed inward from the back of the solar cell 1. Figure 5 The passivation film 3 on the groove surface of the groove 2 on the front of the solar cell 1 is formed under the action of one or more processes of ALD deposition, front plating and protective film plating. The passivation film 3 on the groove surface of the groove 2 on the back of the solar cell 1 is formed under the action of one or more processes of ALD deposition, back plating and protective film plating.
[0060] Embodiment 5
[0061] The embodiment provides a half solar cell, which is formed by breaking any one of the solar cells in the embodiments 1 to 4 between the two opposite grooves. In detail, the half solar cell comprises a split section, and the split section comprises a first region 4 and a second region 5 located at two ends of the first region 4. The appearance of the first region 4 is different from the appearance of the second region 5, and the surface of the second region 5 is covered with a passivation film (not shown).
[0062] The second region 5 is the groove surface of the groove. The passivation film is any one of the passivation films in the embodiments 1 to 4. In detail, the passivation film comprises one or more layers of an aluminum oxide layer, a silicon oxide layer, a silicon nitride layer, a silicon oxynitride layer or an aluminum nitride layer which are stacked in sequence. In a preferred embodiment, the passivation film comprises an aluminum oxide layer, a silicon nitride layer, a silicon oxynitride layer and a silicon oxide layer which are stacked in sequence from the groove surface, and the first region 4 does not have the passivation film. That is, the solar cell is cracked after the film plating process, and is compatible with the existing solar cell preparation process, processing equipment and tooling.
[0063] As shown in the figure, the groove 2 is formed by being recessed inward from the back of the solar cell 1. Figure 6 to Figure 9As shown, the characteristics of the split section of the half solar cell formed after the solar cell piece of the four different slotting structures in Embodiments 1 to 4 is broken are shown. The width of the second region 5 along the thickness direction of the half solar cell is equal to or less than the thickness of the half solar cell. The second region 5 extends from the end of the split section along the length direction of the split section, and the length of the second region 5 is 1 mm to 10 mm.
[0064] It should be noted that the split section refers to the surface features formed on each half solar cell after the solar cell piece is split into at least two half solar cells. In this embodiment, the first region 4 is a surface formed by laser ablation of the portion between the two opposite slots of the solar cell piece to separate the solar cell piece along the two opposite slots and the heating path.
[0065] As described above, since the second region 5 is formed by laser cutting and the first region 4 is formed by laser ablation and thermal stress fracture, the second region 5 has the morphology of laser ablation and the first region 4 has the morphology of mechanical fracture. At the same time, in the direction perpendicular to the split section, the height of the second region 5 is lower than the height of the first region 4. In order to avoid the generation of a large number of dangling bonds and defect states in the step joint caused by the height difference, thereby forming carrier recombination centers to affect the photoelectric conversion efficiency of the solar cell. In this embodiment, the thickness of the passivation film is not less than the height difference between the second region 5 and the first region 4, so as to ensure that the passivation film can effectively cover the step joint.
[0066] In this embodiment, the surface of the passivation film of at least the second region 5 is covered with a fatty alcohol coating layer (not shown) or / and a protective oxide layer (not shown). To effectively block the influence of moisture, other corrosive substances and external pollutants on the passivation film, maintain the functionality of the passivation film and prolong its service life. The fatty alcohol coating layer can be any one or a laminated structure of several of long-chain fatty alcohol, polyvinyl alcohol, polyacrylate, fluorinated polymer. The protective oxide layer can be any one or a laminated structure of several of silicon oxide, titanium oxide, zinc oxide, all of which are conventional materials. The present disclosure does not make specific limitations on the number, type and arrangement order of the layer structure of the fatty alcohol coating layer and the protective oxide layer.
[0067] Embodiment 6
[0068] This embodiment provides a photovoltaic module, which includes a plurality of half solar cell pieces, and the plurality of half solar cell pieces are connected in series to form a cell string, and the half solar cell piece has the same structure as the half solar cell piece in Embodiment 5.
[0069] Finally, it should be noted that the above are only preferred embodiments of the present disclosure and are not intended to limit the present disclosure. Although the present disclosure has been described in detail with reference to the foregoing embodiments, modifications or equivalent replacements can be made to the technical solutions described in the foregoing embodiments, or some technical features thereof can be replaced by equivalents, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present disclosure shall be included in the protection scope of the present disclosure.
Claims
1. Solar cell, characterized in that The front side and the back side have simultaneously or only the back side has a first grid line area and a second grid line area, a non-grid line area is between the first grid line area and the second grid line area, the non-grid line area extends from one side to another side of the solar cell piece along a first direction, both ends of the non-grid line area are respectively provided with a slot, and a slot surface of the slot is provided with a passivation film.
2. The solar cell of claim 1, wherein the first and second electrodes are formed of a material selected from the group consisting of silver, aluminum, and copper. The passivation film comprises one or more layers of superposition of an aluminum oxide layer, a silicon oxide layer, a silicon nitride layer, a silicon oxynitride layer or an aluminum nitride layer.
3. The solar cell of claim 1, wherein the first and second electrodes are formed of a material selected from the group consisting of silver, aluminum, and copper. The passivation film comprises an aluminum oxide layer and a silicon nitride layer which are sequentially stacked; or the passivation film comprises an aluminum oxide layer, a silicon nitride layer, a silicon oxynitride layer and a silicon oxide layer which are sequentially stacked.
4. The solar cell of claim 1, wherein the first and second electrodes are formed of a material selected from the group consisting of silver, aluminum, and copper. The slot extends from the edge of the solar cell piece along the first direction and terminates in the solar cell piece.
5. The solar cell as claimed in claim 4, wherein the first and second electrodes are formed of a material selected from the group consisting of silver, aluminum, and copper. 5 The slot has an extension length of 1mm to 10mm in the first direction, and the slot penetrates the solar cell piece in the thickness direction of the solar cell piece or has a depth less than the thickness of the solar cell piece.
6. A solar cell half, characterized by The first area has a different topography from the second area. The second area is covered with a passivation film. The first area is not provided with the passivation film.
7. The half solar cell according to claim 6, wherein the first and second bus bars are formed by screen printing. The passivation film comprises one or more layers of superposition of an aluminum oxide layer, a silicon oxide layer, a silicon nitride layer, a silicon oxynitride layer or an aluminum nitride layer.
8. The half solar cell according to claim 6, wherein the first and second electrodes are formed by screen printing. The passivation film comprises an aluminum oxide layer and a silicon nitride layer which are sequentially stacked; or the passivation film comprises an aluminum oxide layer, a silicon nitride layer, a silicon oxynitride layer and a silicon oxide layer which are sequentially stacked.
9. The half solar cell according to claim 6, wherein the first and second semiconductor layers are formed of a single semiconductor layer. The second area has a width in the thickness direction of the half solar cell piece equal to or less than the thickness of the half solar cell piece, the second area extends from the end of the split surface along the length direction of the split surface, and the length of the second area is 1mm to 10mm.
10. The half solar cell according to claim 6, wherein the first and second semiconductor layers are formed of a single semiconductor layer. The second area has a laser ablation topography, and the first area has a mechanical fracture topography.
11. The half solar cell of claim 6, wherein the first and second bus bars are formed of a material selected from the group consisting of silver, aluminum, copper, and combinations thereof. The plurality of half solar cell pieces are connected in series to form a cell string.
12. A photovoltaic module characterized by,