Solar cell, photovoltaic module and photovoltaic system
By setting silicon dioxide or silicon oxynitride wear-resistant layers on the front and back of solar cells, the problem of easy scratching and wear of the passivation film layer during the metallization process is solved, thus achieving protection and efficiency improvement of the solar cells.
Patent Information
- Application Number
- CN202520173684.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-24
- Publication Date
- 2026-01-30
- Estimated Expiration
- 2035-01-24
AI Technical Summary
The passivation film layer on the front or back of existing solar cells is easily scratched and worn during the metallization process and module assembly, which affects the efficiency and power of the cells and photovoltaic modules.
Wear-resistant layers are set on the front and back of the solar cell, specifically a stack of silicon dioxide or silicon oxynitride layers with a thickness of 20-100 nm and a refractive index of 1.45-1.65, to protect the passivation film from scratches and wear and to improve passivation performance.
It effectively protects the passivation film layer, maintains the cell efficiency and power generation of solar cells and photovoltaic modules, reduces film scratches, improves photoelectric conversion efficiency, and reduces the cost of laser film opening.
Smart Images
Figure CN223859575U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to solar cell technical field especially relates to a solar cell, photovoltaic module and photovoltaic system. BACKGROUND
[0002] Solar cell is a kind of semiconductor device that can convert solar energy into electric energy, and photogenerated current is generated in solar cell under light condition, and electric energy is output by electrode.In recent years, solar cell production technology is continuously improved, production cost is continuously reduced, conversion efficiency is continuously improved, and solar cell power generation application is increasingly widespread and becomes important energy of electric power supply.
[0003] In prior art, after the front surface or back surface of solar cell is plated with passivation film layer, metallization process and component assembly need to be carried out, in these process, the passivation film layer of the front surface or back surface of cell piece is contacted with equipment belt, roller, process boat / tank body etc., easy to cause the passivation film layer of the front surface or back surface of cell piece to be scratched and abraded, it is difficult to avoid abrasion and scratch, thereby the efficiency and power of solar cell and photovoltaic module composed of solar cell can be affected. SUMMARY
[0004] The utility model provides a kind of solar cell, to solve the problem that the passivation film layer of the front surface or back surface of solar cell in prior art is easy to scratch and abrade.
[0005] The utility model is realized as follows, provide a kind of solar cell, comprising:
[0006] Including silicon wafer, the silicon wafer has oppositely arranged front surface and back surface, the front surface is provided with first passivation film layer, and the back surface is provided with second passivation film layer;
[0007] The side of the first passivation film layer away from the silicon wafer is provided with first wear-resistant layer, the first wear-resistant layer is one or the stack of two of silicon dioxide layer, silicon nitride layer, the thickness of the first wear-resistant layer is 20-100nm, and the refractive index of the first wear-resistant layer is 1.45-1.65;And / or,
[0008] The total thickness of the second passivation film layer is 80-160nm, the side of the second passivation film layer away from the silicon wafer is provided with second wear-resistant layer, the second wear-resistant layer is one or the stack of two of silicon dioxide layer, silicon nitride layer, the thickness of the second wear-resistant layer is 20-100nm, and the refractive index of the second wear-resistant layer is 1.45-1.65.
[0009] Preferably, the thickness of the first wear-resistant layer is 30-90nm, and the refractive index of the first wear-resistant layer is 1.50-1.55.
[0010] Preferably, the thickness of the first wear-resistant layer is 30-50 nm.
[0011] Preferably, the refractive index of the first wear-resistant layer is 1.51-1.54.
[0012] Preferably, the reflectivity of the first wear-resistant layer to sunlight with a wavelength of 250-600 nm is 1.2%-1.57%.
[0013] Preferably, the thickness of the second wear-resistant layer is 40-80 nm, and the refractive index of the second wear-resistant layer is 1.48-1.53.
[0014] Preferably, the thickness of the second wear-resistant layer is 40-60 nm.
[0015] Preferably, the refractive index of the second wear-resistant layer is 1.49-1.52.
[0016] Preferably, the first passivation film layer comprises, from the front side of the silicon wafer to the direction away from the silicon wafer, a front-side passivation layer, an anti-reflection layer in turn, and the first wear-resistant layer is located on the side of the anti-reflection layer away from the silicon wafer.
[0017] Preferably, the refractive index of the first wear-resistant layer is less than the refractive index of the anti-reflection layer.
[0018] Preferably, the anti-reflection layer comprises a first silicon nitride layer and a first silicon oxynitride layer, and the refractive indexes of the first silicon nitride layer, the first silicon oxynitride layer, and the first wear-resistant layer decrease in turn.
[0019] Preferably, the front-side passivation layer comprises, from the front side of the silicon wafer to the direction away from the silicon wafer, a first silicon oxide layer and a first aluminum oxide layer in turn.
[0020] Preferably, the second passivation film layer comprises, from the back side of the silicon wafer to the direction away from the silicon wafer, a tunneling layer, a doped layer, and a back-side passivation layer in turn, and the second wear-resistant layer is located on the side of the back-side passivation layer away from the silicon wafer.
[0021] Preferably, the back-side passivation layer comprises, from the back side of the silicon wafer to the direction away from the silicon wafer, a second silicon oxide layer, a second aluminum oxide layer, a second silicon nitride layer, and a second silicon oxynitride layer in turn, and the second wear-resistant layer is located on the side of the second silicon oxynitride layer away from the silicon wafer, and the refractive indexes of the second silicon nitride layer, the second silicon oxynitride layer, and the second wear-resistant layer decrease in turn.
[0022] Preferably, the first wear-resistant layer has a first thickness at the edge region of the silicon wafer, the first wear-resistant layer has a second thickness at the middle region of the silicon wafer, and the first thickness is greater than the second thickness.
[0023] Preferably, the second wear-resistant layer has a third thickness at the edge region of the silicon wafer, and the second wear-resistant layer has a fourth thickness at the middle region of the silicon wafer, and the third thickness is greater than the fourth thickness.
[0024] The utility model also provides a photovoltaic module, including above-mentioned solar cell.
[0025] The utility model also provides a photovoltaic system, including above-mentioned photovoltaic module.
[0026] The utility model provides a kind of solar cell, by being provided with first wear-resistant layer on the side of first passivation film layer away from silicon wafer, and / or, be provided with second wear-resistant layer on the side of second passivation film layer away from silicon wafer;When first wear-resistant layer is arranged on the front side of silicon wafer, control first wear-resistant layer thickness is 20~100nm, the refractive index of first wear-resistant layer is 1.45~1.65, utilize first wear-resistant layer to promote solar cell front side wear resistance, protect the first passivation film layer of cell front side not easy to scratch and not easy to wear, conducive to keeping solar cell and photovoltaic module good cell efficiency and power generation power;Meanwhile, the thickness range of first wear-resistant layer and the refractive index range of first wear-resistant layer are mutually matched, can realize good antireflection effect of cell front side, and reduce the influence of first wear-resistant layer on cell front side film color, conducive to the film color sorting of solar cell;And, the first wear-resistant layer using silicon dioxide layer or silicon nitride layer has excellent passivation performance, can promote cell front side passivation performance.
[0027] When second wear-resistant layer is arranged on the back of silicon wafer, control second wear-resistant layer thickness is 20~100nm, the refractive index of second wear-resistant layer is 1.45~1.65, utilize second wear-resistant layer to promote solar cell back good wear resistance, protect the second passivation film layer of cell back not easy to scratch and not easy to wear, conducive to keeping solar cell and photovoltaic module good cell efficiency and power generation power;Meanwhile, the thickness range of second wear-resistant layer and the refractive index range of second wear-resistant layer are mutually matched, are conducive to the laser film opening of back film layer, and make second wear-resistant layer have excellent passivation performance, can promote cell back passivation performance. BRIEF DESCRIPTION OF DRAWINGS
[0028] Figure 1 It is a kind of solar cell's structural schematic diagram provided for the utility model embodiment;
[0029] Figure 2 It is another structural schematic diagram of a kind of solar cell provided for the utility model embodiment;
[0030] Figure 3 It is still another structural schematic diagram of a kind of solar cell provided for the utility model embodiment. DETAILED DESCRIPTION
[0031] In order to make the purpose, technical scheme and advantages of the utility model clearer, the utility model will be described in further detail below in combination with the drawings and examples. The examples of the examples are shown in the drawings, wherein the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The examples described below by referring to the drawings are exemplary and are only used to explain the utility model and cannot be understood as limiting the utility model. In addition, it should be understood that the specific examples described herein are only used to explain the utility model and are not used to limit the utility model.
[0032] In the description of the utility model, it should be understood that the orientation or position relationship indicated by the terms "upper", "lower", "back", "front" and the like is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore it cannot be understood as limiting the utility model.
[0033] In the utility model, unless otherwise explicitly specified and limited, the "upper" or "lower" of the first feature to the second feature can include that the first and second features are in direct contact, or the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the "over", "above" and "on" of the first feature to the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The "under", "below" and "under" of the first feature to the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.
[0034] The following disclosure provides many different embodiments or examples for implementing different structures of the utility model. In order to simplify the disclosure of the utility model, the components and settings of specific examples are described below. Of course, they are only examples and the purpose is not to limit the utility model. In addition, the utility model can repeatedly refer to numerals and / or reference letters in different examples, and such repetition is for the purpose of simplification and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed. In addition, the utility model provides examples of various specific processes and materials, but those skilled in the art can realize the application of other processes and / or the use of other materials.
[0035] The utility model provides a solar cell through setting up first wear -resisting layer on the side of first passivation film layer away from silicon wafer, and / or, setting up second wear -resisting layer on the side of second passivation film layer away from silicon wafer, when setting up first wear -resisting layer on the front side of silicon wafer, control first wear -resisting layer thickness is 20~100nm, the refractive index of first wear -resisting layer is 1.45~1.65, utilize first wear -resisting layer to promote solar cell front side good wear resistance, protect the first passivation film layer of cell front side not easy to scratch and not easy to wear, it is favorable to keep solar cell and photovoltaic module good cell efficiency and power generation power, simultaneously, the thickness range of first wear -resisting layer and the refractive index range of first wear -resisting layer mutually collocates, can realize solar cell front side good antireflection effect, and as far as possible reduce the influence of first wear -resisting layer to front film color, it is favorable to solar cell's film color sorting, and first wear -resisting layer has excellent passivation performance, can promote cell front side passivation performance,
[0036] When setting up second wear -resisting layer on the back of silicon wafer, control second wear -resisting layer thickness is 20~100nm, the refractive index of second wear -resisting layer is 1.45~1.65, utilize second wear -resisting layer to promote solar cell back good wear resistance, protect the second passivation film layer of cell back not easy to scratch and not easy to wear, it is favorable to keep solar cell and photovoltaic module good cell efficiency and power generation power, and second wear -resisting layer is in this thickness range and this refractive index range, it is favorable to the laser open membrane of back membrane layer, and second wear -resisting layer has excellent passivation performance, can promote cell back passivation performance.
[0037] Please refer to Figures 1-2 The utility model provides a solar cell, including silicon wafer 1, silicon wafer 1 has opposite setting front 11 and back 12, and the front 11 is provided with first passivation film layer 2, and the back is provided with second passivation film layer 3,
[0038] The side of first passivation film layer 2 away from silicon wafer 1 is provided with first wear -resisting layer 4, and the first wear -resisting layer 4 is one or the lamination of two of silicon dioxide layer, silicon nitride layer, and the thickness of first wear -resisting layer 4 is 20~100nm, and the refractive index of first wear -resisting layer 4 is 1.45~1.65, and / or,
[0039] The total thickness of second passivation film layer 3 is 80~160nm, and the side of second passivation film layer 3 away from silicon wafer 1 is provided with second wear -resisting layer 5, and the second wear -resisting layer 5 is one or the lamination of two of silicon dioxide layer, silicon nitride layer, and the thickness of second wear -resisting layer 5 is 20~100nm, and the refractive index of second wear -resisting layer 5 is 1.45~1.65.
[0040] In the embodiment of the utility model, the solar cell can be a back contact solar cell or a double-sided contact solar cell. Specifically, in the case of a back contact solar cell, the conductive regions of P and N polarities are arranged on the back surface of the silicon wafer 1 at intervals. In the case of a double-sided contact solar cell, the conductive regions of P and N polarities are arranged on the front surface 11 and the back surface 12 of the silicon wafer 1, respectively. For example, the solar cell can be an IBC solar cell, a Topcon solar cell, or a Perc solar cell. The first wear-resistant layer 4 has the same anti-wear principle in different cell types, and both utilize the high hardness and wear resistance of the silicon dioxide layer or the silicon nitride oxide layer, and have good thermal stability and corrosion resistance. The first wear-resistant layer 4 is arranged on the outermost side of the passivation film layer on the front surface 11 or the back surface 12 of the cell, thereby increasing the scratch resistance and wear resistance of the passivation film layer on the front surface 11 or the back surface 12 of the cell. Among them, Figure 2 The illustrated solar cell is a back contact solar cell.
[0041] In the embodiment of the utility model, the first wear-resistant layer 4 can be arranged only on the front surface 11 of the silicon wafer 1, which can prevent the first passivation film layer 2 on the front surface 11 of the solar cell from being easily scratched or worn. The second wear-resistant layer 5 can be arranged only on the back surface 12 of the silicon wafer 1, which can prevent the second passivation film layer 3 on the back surface 12 of the solar cell from being easily scratched or worn.
[0042] In the embodiment of the utility model, the first wear-resistant layer 4 is arranged on the side of the first passivation film layer 2 away from the silicon wafer 1, the first wear-resistant layer 4 is one or a stack of two of a silicon dioxide layer and a silicon nitride oxide layer, the thickness of the first wear-resistant layer 4 is controlled to be 20-100 nm, and the refractive index of the first wear-resistant layer 4 is 1.45-1.6. The thickness range of the first wear-resistant layer 4 and the refractive index range of the first wear-resistant layer 4 cooperate with each other. On the one hand, the first wear-resistant layer 4 has good wear resistance in this thickness range and this refractive index range, which protects the first passivation film layer 2 on the front surface 11 of the cell from being easily scratched and worn, reduces scratches on the front surface of the cell, and is beneficial to maintaining good cell efficiency and power generation of the solar cell and the photovoltaic module composed of the solar cell. On the other hand, the added first wear-resistant layer 4 can achieve good antireflection effect on the front surface 11 of the solar cell, which is beneficial to maintaining good photoelectric conversion efficiency of the cell, and can reduce the influence of the first wear-resistant layer 4 on the film color of the front surface 11 of the cell as much as possible, which is beneficial to the film color sorting of the solar cell. In addition, the silicon dioxide layer or the silicon nitride oxide layer is used as the first wear-resistant layer 4, which has excellent passivation performance, can improve the passivation performance of the front surface 11 of the cell, and further improve the cell efficiency.
[0043] In the embodiment of the utility model, the second wear -resisting layer 5 is provided with one or two of the lamination of silicon dioxide layer, silicon nitride layer on the side of the second passivation film layer 3 away from the silicon wafer 1, the thickness of the second wear -resisting layer 5 is controlled to be 20~100nm, and the refractive index of the second wear -resisting layer 5 is 1.45~1.6. The thickness range of the second wear -resisting layer 5 and the refractive index range of the second wear -resisting layer 5 cooperate with each other, on the one hand, the second wear -resisting layer 5 in this thickness range and this refractive index range can make the second wear -resisting layer 5 have good wear resistance, protect the second passivation film layer 3 of the battery back 12 from being easily scratched and worn, reduce the battery back scratch, and be beneficial to maintaining the good battery efficiency and power generation power of the solar cell and the photovoltaic module composed of the solar cell, on the other hand, the second wear -resisting layer 5 added may affect the laser film opening of the film layer of the battery back 12, the second wear -resisting layer 5 with too high refractive index can absorb more laser, resulting in the large power required for laser film opening, the refractive index and the film layer density are positively correlated, and the second wear -resisting layer 5 with too low refractive index has poor density and poor wear resistance, therefore, the thickness range of the second wear -resisting layer 5 and the refractive index range of the second wear -resisting layer 5 are set to the above range, the thickness range of the second wear -resisting layer 5 and the refractive index range cooperate with each other, the second wear -resisting layer 5 can maintain good wear resistance, and the laser film opening of the back 12 film layer in the subsequent metallization process is facilitated, the laser power is reduced, the cost is reduced, the laser power is avoided to be too large to damage the second passivation film layer 3, and good battery performance is ensured.
[0044] As a preferred embodiment of the utility model, the first wear -resisting layer 4 is arranged on the front surface 11 of the silicon wafer 1, and the second wear -resisting layer 5 is arranged on the back 12 of the silicon wafer 1, the first wear -resisting layer 4 is used to protect the first passivation film layer 2 of the front surface 11, which can prevent the first passivation film layer 2 of the front surface 11 of the solar cell from being easily worn or scratched, prevent the second passivation film layer 3 of the back 12 of the solar cell from being easily worn or scratched, and realize the protection of the double-side passivation film layer of the solar cell.
[0045] In the embodiment of the utility model, the thickness and refractive index of the first wear -resisting layer 4 can be flexibly set according to actual conditions. The thickness of the first wear -resisting layer 4 can be any value in 20~100nm, for example, the thickness of the first wear -resisting layer 4 can be any value in 20nm, 25nm, 30nm, 35nm, 40nm, 42nm, 45nm, 50nm, 51nm, 52nm, 53nm, 55nm, 58nm, 60nm, 62nm, 65nm, 70nm, 75nm, 80nm, 85nm, 90nm, 96nm, 100nm.
[0046] The refractive index of the first wear-resistant layer 4 can be any value in the range of 1.45-1.60; for example, the refractive index of the first wear-resistant layer 4 can be any value in the range of 1.45, 1.46, 1.47, 1.48, 1.49, 1.50, 1.51, 1.52, 1.53, 1.54, 1.55, 1.56, 1.57, 1.58, 1.59, 1.60, 1.61, 1.62, 1.63, 1.64, 1.65.
[0047] The thickness of the second wear-resistant layer 5 can be any value in the range of 20-100 nm; for example, the thickness of the second wear-resistant layer 5 can be any value in the range of 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 42 nm, 45 nm, 50 nm, 51 nm, 52 nm, 53 nm, 55 nm, 58 nm, 60 nm, 62 nm, 65 nm, 70 nm, 75 nm, 80 nm, 85 nm, 90 nm, 96 nm, 100 nm.
[0048] The refractive index of the second wear-resistant layer 5 can be any value in the range of 1.45-1.60; for example, the refractive index of the first wear-resistant layer 4 can be any value in the range of 1.45, 1.46, 1.47, 1.48, 1.49, 1.50, 1.51, 1.52, 1.53, 1.54, 1.55, 1.56, 1.57, 1.58, 1.59, 1.60, 1.61, 1.62, 1.63, 1.64, 1.65.
[0049] In the embodiments of the present application, the thickness and the refractive index of the second wear-resistant layer 5 can be flexibly set according to actual conditions, and the thickness and the refractive index of the second wear-resistant layer 5 can be the same as or different from the thickness and the refractive index of the first wear-resistant layer 4. For example, the thickness of the second wear-resistant layer 5 is 55 nm, and the refractive index of the second wear-resistant layer 5 is 1.51; the thickness of the first wear-resistant layer 4 is 40 nm, and the refractive index of the first wear-resistant layer 4 is 1.53.
[0050] As an embodiment of the present application, the thickness of the first wear-resistant layer 4 is 30-90 nm, and the refractive index of the first wear-resistant layer 4 is 1.50-1.55.
[0051] In the embodiment, the thickness of the first wear-resistant layer 4 is preferably 30-90 nm, the refractive index of the first wear-resistant layer 4 is preferably 1.50-1.55, and the thickness range and the refractive index range of the first wear-resistant layer 4 are matched with each other, which can further ensure that the first wear-resistant layer 4 has good wear resistance; on the other hand, the front surface 11 of the solar cell has good antireflection effect, which is beneficial to maintaining the good photoelectric conversion efficiency of the cell and further reducing the influence of the first wear-resistant layer 4 on the film color of the front surface 11 of the cell, which is suitable for the film color sorting scheme of the current solar cell and is beneficial to the film color sorting of the solar cell; at the same time, the first wear-resistant layer 4 has more excellent passivation performance, which can further improve the passivation performance of the first wear-resistant layer 4 on the front surface 11 of the cell.
[0052] As an embodiment of the utility model, the thickness of the first wear-resistant layer 4 is 30-50 nm.
[0053] In the embodiment, the thickness of the first wear-resistant layer 4 is preferably 30-50 nm, which ensures that the first wear-resistant layer 4 has good wear resistance, realizes more excellent antireflection effect of the front surface 11 of the solar cell, minimizes the influence of the first wear-resistant layer 4 on the film color of the front surface 11 of the cell, is beneficial to the film color sorting of the solar cell, and makes the first wear-resistant layer 4 have excellent passivation performance, thereby balancing the above-mentioned effects.
[0054] As an embodiment of the utility model, the refractive index of the first wear-resistant layer 4 is 1.51-1.54.
[0055] In the embodiment, the refractive index of the first wear-resistant layer 4 is preferably 1.51-1.54, which can further realize more excellent antireflection effect of the front surface 11 of the solar cell.
[0056] As an embodiment of the utility model, the reflectivity of the first wear-resistant layer 4 to sunlight with a wavelength of 250-600 nm is 1.2%-1.57%.
[0057] In the embodiment, the reflectivity of the first wear-resistant layer 4 to sunlight with a wavelength of 250-600 nm is controlled to be 1.2%-1.57%, which makes the first wear-resistant layer 4 have excellent antireflection effect to sunlight with a wavelength of 250-600 nm, is beneficial to increasing the absorption of the solar cell to sunlight with a wavelength of 250-600 nm, and is beneficial to improving the conversion efficiency of the cell. For example, the reflectivity of the sunlight can be any value in 1.2%, 1.22%, 1.30%, 1.35%, 1.37%, 1.39%, 1.40%, 1.42%, 1.45%, 1.5%, 1.53%, and 1.57%.
[0058] As an embodiment of the present application, the thickness of the second wear-resistant layer 5 is 40-80nm, and the refractive index of the second wear-resistant layer 5 is 1.48-1.53.
[0059] In the embodiment, the thickness of the second wear-resistant layer 5 is preferably 40-80nm, and the refractive index of the second wear-resistant layer 5 is preferably 1.48-1.53, and the thickness range and the refractive index range of the second wear-resistant layer 5 are matched with each other, so that the second wear-resistant layer 5 has good wear resistance, and further facilitates the laser opening of the film layer of the back surface 12, and the second wear-resistant layer 5 has excellent passivation performance, and the second wear-resistant layer 5 maintains good passivation performance on the back surface 12 of the battery.
[0060] As an embodiment of the present application, the thickness of the second wear-resistant layer 5 is 40-60nm.
[0061] In the embodiment, the thickness of the second wear-resistant layer 5 is preferably 40-60nm, and under the premise of ensuring that the second wear-resistant layer 5 has good wear resistance, the laser opening of the film layer of the back surface 12 is further facilitated, and the good passivation performance of the second wear-resistant layer 5 is further maintained.
[0062] As an embodiment of the present application, the refractive index of the second wear-resistant layer 5 is 1.49-1.52.
[0063] In the embodiment, the refractive index of the second wear-resistant layer 5 is further preferably 1.49-1.52, and under the premise of ensuring that the second wear-resistant layer 5 has good wear resistance, the laser opening of the film layer of the back surface 12 is further facilitated.
[0064] As an embodiment of the present application, the first passivation film layer 2 comprises a front surface passivation layer and a reflection-reducing layer which are sequentially stacked from the front surface 11 of the silicon wafer 1 to the direction away from the silicon wafer 1, and the first wear-resistant layer 4 is located on the side of the reflection-reducing layer away from the silicon wafer 1.
[0065] In the embodiment, the front surface passivation layer mainly plays a passivation role of the front surface 11 of the silicon wafer 1, the reflection-reducing layer mainly plays a reflection-reducing role of the silicon wafer 1, and the light utilization rate of the battery front surface 11 is improved. The first wear-resistant layer 4 is located on the side of the first reflection-reducing layer away from the silicon wafer 1, that is, the first wear-resistant layer 4 is located on the outermost side of the battery front surface 11, so as to protect the first passivation film layer 2, reduce the degree of wear or scratch of the first passivation film layer 2, and thus maintain the good performance of the first passivation film layer 2.
[0066] As an embodiment of the present application, the refractive index of the first wear-resistant layer 4 is less than the refractive index of the reflection-reducing layer.
[0067] In the embodiment, the first wear-resistant layer 4 is located outside the antireflection layer, the refractive index of the first wear-resistant layer 4 is controlled to be less than the refractive index of the antireflection layer, the absorption of the solar light by the front surface 11 of the battery is facilitated, and the conversion efficiency of the battery is improved.
[0068] As an embodiment of the utility model, the front surface passivation layer comprises a first silicon oxide layer 21 and a first aluminum oxide layer 22 which are sequentially stacked from the front surface 11 of the silicon wafer 1 to the direction away from the silicon wafer 1.
[0069] In the embodiment, the front surface passivation layer comprises a first silicon oxide layer 21 and a first aluminum oxide layer 22 which are sequentially stacked to form a laminated structure, the front surface 11 is well passivated, and the absorption of the solar light by the front surface 11 of the battery is facilitated.
[0070] As an embodiment of the utility model, the antireflection layer comprises a first silicon nitride layer 23 and a first silicon oxynitride layer 24, and the refractive indexes of the first silicon nitride layer 23, the first silicon oxynitride layer 24 and the first wear-resistant layer 4 decrease sequentially. The first silicon nitride layer 23 can specifically comprise 1-4 layers of silicon nitride films, and the first silicon oxynitride layer 24 can specifically comprise 1-4 layers of silicon oxynitride films.
[0071] In the embodiment, the first antireflection layer comprises a first silicon nitride layer 23 and a first silicon oxynitride layer 24 which are sequentially stacked to form a laminated structure, the antireflection effect is good, the absorption of the solar light by the front surface 11 of the battery is facilitated, and the absorption effect of the solar light by the front surface 11 of the battery is further improved due to the fact that the refractive indexes of the first silicon nitride layer 23, the first silicon oxynitride layer 24 and the first wear-resistant layer 4 decrease sequentially.
[0072] As an embodiment of the utility model, the second passivation film layer 3 comprises a tunneling layer 31, a doped layer 32 and a back surface passivation layer (not numbered) which are sequentially stacked from the back surface 12 of the silicon wafer 1 to the direction away from the silicon wafer 1, and the second wear-resistant layer 5 is located on the side of the back surface passivation layer away from the silicon wafer 1.
[0073] In the embodiment, the solar cell is a back contact solar cell, the second passivation film layer 3 comprises a tunneling layer 31, a doped layer 32 and a back surface passivation layer which are sequentially stacked from the back surface 12 of the silicon wafer 1 to the direction away from the silicon wafer 1. The doped layer 32 can be a P-type doped layer or an N-type doped layer. The doped layer of the P-type doped area of the back surface 12 of the silicon wafer 1 is a P-type doped layer, and the doped layer of the N-type doped area of the back surface 12 of the silicon wafer 1 is an N-type doped layer. The second wear-resistant layer 5 is located on the side of the back surface passivation layer away from the silicon wafer 1, the second wear-resistant layer 5 protects the second passivation film layer 3 composed of the tunneling layer 31, the doped layer 32 and the back surface passivation layer, prevents the second passivation film layer 3 from being abraded or scratched, and improves the structural reliability of the second passivation film layer 3. The back surface passivation layer can be one or a combination of a silicon oxide layer, an aluminum oxide, a silicon nitride layer and a silicon oxynitride layer.
[0074] As an embodiment of the utility model, the back passivation layer includes a second silicon oxide layer 33, a second aluminum oxide layer 34, a second silicon nitride layer 35 and a second silicon oxynitride layer 36 which are sequentially stacked from the back surface 12 of the silicon wafer 1 to the direction away from the silicon wafer 1, and the second wear-resistant layer 5 is located on the side of the second silicon oxynitride layer 36 away from the silicon wafer 1, and the refractive indexes of the second silicon nitride layer 35, the second silicon oxynitride layer 36 and the second wear-resistant layer 5 decrease sequentially.
[0075] In the embodiment, the film layer number of the second silicon oxide layer 33, the second aluminum oxide layer 34 and the second silicon nitride layer 35 is not limited, which can be single layer or multiple layers. For example, the second silicon nitride layer 35 includes two layers of silicon nitride thin films, and the second silicon oxynitride layer 36 includes two layers of silicon oxynitride thin films.
[0076] In the embodiment, the refractive indexes of the second silicon nitride layer 35, the second silicon oxynitride layer 36 and the second wear-resistant layer 5 decrease sequentially, which is beneficial to reducing the reflectivity of the back surface 12 of the battery irradiating sunlight, ensuring the reflection effect of the long-wave band light transmitted by the front surface 11 of the battery, and improving the battery efficiency.
[0077] In the embodiment of the utility model, the total thickness of the second passivation film layer 3 is 80-160 nm, which can avoid that the total thickness of the second passivation film layer 3 is too large or too small. If the total thickness of the second passivation film layer 3 is greater than 160 nm and the second wear-resistant layer 5 is matched, it is not conducive to the laser opening film of the back surface. If the total thickness of the second passivation film layer 3 is greater than 80 nm and the second wear-resistant layer 5 is matched, it is not conducive to the wear resistance of the back surface 12 of the battery. Therefore, under the premise that the total thickness of the second passivation film layer 3 is set to 80-160 nm, and the second wear-resistant layer 5 with a thickness of 20-100 nm and a refractive index of 1.45-1.65 is matched, the good wear resistance effect of the back surface 12 of the battery can be realized, and the laser opening film of the back surface 12 of the battery is facilitated, and the laser opening film power is avoided to be too large.
[0078] Please refer to Figure 3 As an embodiment of the utility model, the first wear-resistant layer 4 has a first thickness d1 in the edge area of the silicon wafer 1, and the first wear-resistant layer 4 has a second thickness d2 in the middle area of the silicon wafer 1, and the first thickness d1 is greater than the second thickness d2.
[0079] The first thickness d1 of the first wear-resistant layer 4 in the edge area of the silicon wafer 1 is the average thickness or the maximum thickness of the first wear-resistant layer 4 in the edge area of the silicon wafer 1. The second thickness d2 of the first wear-resistant layer 4 in the middle area of the silicon wafer 1 is the average thickness or the maximum thickness of the first wear-resistant layer 4 in the middle area of the silicon wafer 1.
[0080] In this embodiment, since there are more dangling bonds and lattice defects at the edge of the silicon wafer 1 of the solar cell, the passivation effect of the edge region of the silicon wafer 1 is worse than that of the middle region of the silicon wafer 1. Therefore, the thickness of the first wear-resistant layer 4 at the edge region of the silicon wafer 1 is set to be thicker than that at the middle region of the silicon wafer 1. This is beneficial to improving the passivation effect of the edge region of the front side 11 of the silicon wafer 1, facilitating the balance of passivation effects in each region of the front side 11 of the silicon wafer 1, improving cell efficiency, and enhancing the wear resistance of the edge region of the front side 11 of the silicon wafer 1.
[0081] As an embodiment of the present invention, the second wear-resistant layer 5 has a third thickness d3 in the edge region of the silicon wafer 1 and a fourth thickness d4 in the middle region of the silicon wafer 1, wherein the third thickness d3 is greater than the fourth thickness d4.
[0082] The third thickness d3 of the second wear-resistant layer 5 located in the edge region of the silicon wafer 1 is the average thickness or maximum thickness of the second wear-resistant layer 5 located in the edge region of the silicon wafer 1. The third thickness d4 of the second wear-resistant layer 5 located in the middle region of the silicon wafer 1 is the average thickness or maximum thickness of the second wear-resistant layer 5 located in the middle region of the silicon wafer 1.
[0083] In this embodiment, since there are more dangling bonds and lattice defects at the edge of the silicon wafer 1 of the solar cell, the passivation effect of the edge region of the silicon wafer 1 is worse than that of the middle region of the silicon wafer 1. Therefore, the third thickness d3 is set to be greater than the fourth thickness d4, that is, the thickness of the second wear-resistant layer 5 at the edge region of the silicon wafer 1 is thicker than that at the middle region of the silicon wafer 1. This is beneficial to improving the passivation effect of the edge region of the back side 12 of the silicon wafer 1, and to balancing the passivation effect of each region of the back side 12 of the silicon wafer 1. This is beneficial to improving the cell efficiency and can also improve the wear resistance of the edge region of the back side 12 of the silicon wafer 1.
[0084] To further demonstrate the technical effects achieved by this utility model, the inventors conducted the following comparative experiments:
[0085] Set up control group 1 and experimental group 1:
[0086] Control group 1: None of the battery cells had a first wear-resistant layer on the front. The battery cells in control group 1 were numbered A1, A2, ..., A10.
[0087] Experimental Group 1: Each battery cell has a first wear-resistant layer on its front side. The other structures of the battery cells in Experimental Group 1 are exactly the same as those in Control Group 1. The battery cells in Experimental Group 1 are numbered B1, B2, ..., B12 in sequence.
[0088] Under the same test conditions, the percentage of the front scratch area of each cell in control group 1 (the percentage of the front scratch area to the front area of the silicon wafer) is shown in Table 1.
[0089] Table 1
[0090]
[0091] The first wear-resistant layer thickness, the first wear-resistant layer refractive index, the front scratch area ratio (the percentage of the front scratch area to the front area of the silicon wafer), the front reflectivity, and the front film color related data of each battery piece in the experimental group one are measured and shown in Table 2.
[0092] Table 2
[0093]
[0094] As can be seen from Table 1 and Table 2, the front of each battery piece in the control group one is not provided with a first wear-resistant layer, and under the same test conditions, the scratch area ratio of the battery piece in the control group one is larger than that of each battery piece in the experimental group one, that is, the first wear-resistant layer provided on the front of the battery piece can significantly reduce the scratch area and reduce the generation of scratches; at the same time, as can be seen from Table 2, the thickness of the first wear-resistant layer is set to 20-100 nm, the refractive index of the first wear-resistant layer is set to 1.45-1.65, which can make the front of the battery piece have good scratch and wear resistance, and has a relatively low front reflectivity, and has a relatively small influence on the film color.
[0095] The control group two and the experimental group two are set:
[0096] The control group two: the back of each battery piece in the control group two is not provided with a wear-resistant layer, and the serial numbers of the battery pieces in the control group two are C1, C2, ……C10 in turn;
[0097] The experimental group two: the back of each battery piece in the experimental group two is provided with a second wear-resistant layer, and the other structures of the battery pieces are the same as those of the control group two; the serial numbers of the battery pieces in the experimental group two are D1, D2, ……D13 in turn;
[0098] 1. The related data of each battery piece in the control group two are measured and shown in Table 3;
[0099] Table 3
[0100]
[0101] 2. The related data of each battery piece in the experimental group two are measured and shown in Table 4:
[0102] Table 4
[0103]
[0104]
[0105] As shown in Tables 3 and 4, under the same test conditions, the scratch area on the back of the cells in control group 2 was significantly larger than that on the back of the cells in experimental group 2. The addition of a second wear-resistant layer on the back of the cells in experimental group 2 significantly reduced the scratch area and the occurrence of scratches. The back of the cells in experimental group 2 showed a significant anti-wear effect, and scratches were less likely to appear on the back of the cells. At the same time, as shown in Table 4, the thickness of the second wear-resistant layer was set at 20-100 nm, and the refractive index of the second wear-resistant layer was set at 1.45-1.65. This gave the back of the cells good anti-scratch and wear performance, and kept the laser decoction power on the back low, which was beneficial for laser decoction on the back.
[0106] Design experimental groups three, four, and five:
[0107] Experimental Group 3: The back of the batteries in Experimental Group 3 are all provided with a second wear-resistant layer, and the thickness of the second wear-resistant layer is 50nm. The battery cells in Experimental Group 3 are numbered E1, E2, ..., E5, and the total thickness of the second passivation film layer corresponding to each battery cell is 50nm, 55nm, 60nm, 70nm, and 80nm, respectively.
[0108] The relevant data of the three battery cells in the experimental group are shown in Table 5:
[0109] Table 5
[0110] Battery piece number E1 E2 E3 E4 E5 Backside scratch area ratio 0.11％ 0.10％ 0.12％ 0.11％ 0.11％ Laser opening film power (w) 1.0 1.11 1.2 1.3 1.4
[0111] Experimental Group 4: The back of the batteries in Experimental Group 4 are all provided with a second wear-resistant layer, and the thickness of the second wear-resistant layer is 50nm; the battery cells in Experimental Group 4 are numbered F1, F2...F5 in sequence; and the total thickness of the second passivation film layer corresponding to each battery cell is 85nm, 100nm, 120nm, 140nm, and 160nm.
[0112] The relevant data of each of the four battery cells in the experimental group are shown in Table 6 below:
[0113] Table 6
[0114]
[0115]
[0116] Experimental Group 5: All batteries in Experimental Group 5 have a second wear-resistant layer on their backs, with a thickness of 50 nm. The battery cells in Experimental Group 5 are numbered G1, G2, ..., G5. The total thickness of the second passivation film for each battery cell is 165 nm, 180 nm, 200 nm, 220 nm, and 240 nm, respectively. The relevant data for each battery cell in Experimental Group 4 are shown in Table 7 below.
[0117] Table 7
[0118] G1 G2 G3 G4 G5 Backside scratch area ratio 0.05％ 0.05％ 0.04％ 0.04％ 0.04％ Laser opening film power (w) 2.0 2.1 2.2 2.3 2.4
[0119] As can be seen from Table 5 to Table 7, the total thickness of the second passivation film layer on the back of the battery is controlled in the range of 80-160nm, and the second wear-resistant layer is matched, which can make the battery back anti-wear effect better, and at the same time, the back laser opening film power is lower, which is beneficial to the back laser opening film.
[0120] The utility model embodiment further provides a photovoltaic module, the photovoltaic module includes the solar cell of above-mentioned embodiment. It needs to be explained that the photovoltaic module has same or similar beneficial effect with above-mentioned solar cell, and the correlation between both can be mutually referred, in order to avoid repetition, here will not be repeated.
[0121] In the embodiment, the plurality of solar cells in the photovoltaic module can be sequentially connected together to form a cell string, thereby realizing the series connection of the current, for example, the connection of the solar cells can be realized by setting a welding strip (bus bar, interconnecting strip), a conductive back plate and the like.
[0122] It can be understood that in such an embodiment, the photovoltaic module can further include a metal frame, a back plate, photovoltaic glass and a glue film. The glue film can be filled between the front and back of the solar cell and the photovoltaic glass, adjacent solar cells and the like, and can be a transparent glue with good light transmission and aging resistance, for example, the glue film can be EVA glue film or POE glue film, which can be selected according to actual conditions, and is not limited herein.
[0123] The photovoltaic glass can be covered on the glue film on the front of the solar cell, and the photovoltaic glass can be super white glass, which has high light transmittance, high transparency and excellent physical, mechanical and optical properties, for example, the light transmittance of the super white glass can be more than 92%, which can protect the solar cell without affecting the efficiency of the solar cell as much as possible. At the same time, the glue film can bond the photovoltaic glass and the solar cell together, and the existence of the glue film can seal and insulate the solar cell and prevent water and moisture.
[0124] The back plate can be attached to the glue film on the back of the solar cell, and the back plate can protect and support the solar cell, has reliable insulation, water resistance and aging resistance, and the back plate can have multiple choices, which can be tempered glass, organic glass, aluminum alloy TPT composite glue film and the like, which can be set according to actual conditions, and is not limited herein. The whole composed of the back plate, the solar cell, the glue film and the photovoltaic glass can be arranged on the metal frame, and the metal frame serves as the main external supporting structure of the whole solar photovoltaic module, and can stably support and install the solar photovoltaic module, for example, the solar photovoltaic module can be installed at the position required to be installed through the metal frame.
[0125] The utility model embodiment further provides a photovoltaic system, the photovoltaic system includes the photovoltaic module of above -mentioned embodiment. It needs to explain, this photovoltaic system with above -mentioned solar cell has same or similar beneficial effect, and the correlation between both can be mutually referred to, in order to avoid repetition, here will not repeat.
[0126] In the embodiment, the photovoltaic system can be applied in a photovoltaic power station, such as a ground power station, a roof power station, a water surface power station, etc., and can also be applied on a device or apparatus that utilizes solar energy to generate electricity, such as a user solar power source, a solar street lamp, a solar car, a solar building, etc. Of course, it can be understood that the application scenarios of the photovoltaic system are not limited to this, that is, the photovoltaic system can be applied in all fields that need to utilize solar energy to generate electricity. Taking a photovoltaic power generation system network as an example, the photovoltaic system can include a photovoltaic array, a combiner box, and an inverter, the photovoltaic array can be an array combination of a plurality of solar photovoltaic components, for example, a plurality of solar photovoltaic components can form a plurality of photovoltaic arrays, the photovoltaic arrays are connected to the combiner box, the combiner box can combine the current generated by the photovoltaic arrays, the combined current flows through the inverter to convert into alternating current required by a power grid, and then is connected to a power network to realize solar power supply.
[0127] In the description of the present specification, the description referring to the terms "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of the present utility model. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.
[0128] The above is merely a preferred embodiment of the present utility model, and is not intended to limit the present utility model, and any modification, equivalent replacement, and improvement, etc. made within the spirit and principle of the present utility model shall be included in the protection scope of the present utility model.
Claims
1. A solar cell, characterized by, The silicon wafer has a front surface and a back surface arranged oppositely, the front surface is provided with a first passivation film layer, and the back surface is provided with a second passivation film layer; The first passivation film layer is provided with a first wear-resistant layer on a side away from the silicon wafer, the first wear-resistant layer is one or a stack of two of a silicon dioxide layer and a silicon oxynitride layer, the thickness of the first wear-resistant layer is 20-100 nm, and the refractive index of the first wear-resistant layer is 1.45-1.65; and / or, The total thickness of the second passivation film layer is 80-160 nm, the second passivation film layer is provided with a second wear-resistant layer on a side away from the silicon wafer, the second wear-resistant layer is one or a stack of two of a silicon dioxide layer and a silicon oxynitride layer, the thickness of the second wear-resistant layer is 20-100 nm, and the refractive index of the second wear-resistant layer is 1.45-1.
65.
2. The solar cell according to claim 1, characterized in that, The thickness of the first wear-resistant layer is 30-90 nm, and the refractive index of the first wear-resistant layer is 1.50-1.
55.
3. The solar cell according to claim 1, characterized in that, The thickness of the first wear-resistant layer is 30-50 nm.
4. The solar cell of claim 1, wherein The refractive index of the first wear-resistant layer is 1.51-1.
54.
5. The solar cell of claim 1, wherein The reflectivity of the first wear-resistant layer to sunlight with a wavelength of 250-600 nm is 1.2%-1.57%.
6. The solar cell of claim 1, wherein The thickness of the second wear-resistant layer is 40-80 nm, and the refractive index of the second wear-resistant layer is 1.48-1.
53.
7. The solar cell of claim 1, wherein The thickness of the second wear-resistant layer is 40-60 nm.
8. The solar cell of claim 1, wherein, The refractive index of the second wear-resistant layer is 1.49-1.
52.
9. The solar cell of claim 1, wherein, The first passivation film layer comprises, from the front surface of the silicon wafer to a direction away from the silicon wafer, a front surface passivation layer and an anti-reflection layer arranged in sequence, and the first wear-resistant layer is located on a side of the anti-reflection layer away from the silicon wafer.
10. The solar cell of claim 9, wherein, The refractive index of the first wear-resistant layer is less than the refractive index of the anti-reflection layer.
11. The solar cell of claim 9, wherein, The anti-reflection layer comprises a first silicon nitride layer and a first silicon oxynitride layer, and the refractive indexes of the first silicon nitride layer, the first silicon oxynitride layer and the first wear-resistant layer decrease in sequence.
12. The solar cell of claim 9, wherein, The front surface passivation layer comprises, from the front surface of the silicon wafer to a direction away from the silicon wafer, a first silicon oxide layer and a first aluminum oxide layer arranged in sequence.
13. The solar cell of claim 1, wherein, The second passivation film layer comprises, from the back surface of the silicon wafer to a direction away from the silicon wafer, a tunneling layer, a doped layer and a back surface passivation layer arranged in sequence, and the second wear-resistant layer is located on a side of the back surface passivation layer away from the silicon wafer.
14. The solar cell of claim 13, wherein, The back surface passivation layer comprises, from the back surface of the silicon wafer to a direction away from the silicon wafer, a second silicon oxide layer, a second aluminum oxide layer, a second silicon nitride layer and a second silicon oxynitride layer arranged in sequence, and the second wear-resistant layer is located on a side of the second silicon oxynitride layer away from the silicon wafer, and the refractive indexes of the second silicon nitride layer, the second silicon oxynitride layer and the second wear-resistant layer decrease in sequence.
15. The solar cell of claim 1, wherein, The first wear-resistant layer has a first thickness in an edge region of the silicon wafer, and the first wear-resistant layer has a second thickness in a middle region of the silicon wafer, and the first thickness is greater than the second thickness.
16. The solar cell of claim 1, wherein, The second wear-resistant layer has a third thickness in an edge region of the silicon wafer, and the second wear-resistant layer has a fourth thickness in a middle region of the silicon wafer, and the third thickness is greater than the fourth thickness.
17. A photovoltaic module, characterized by A solar cell comprising any one of claims 1 to 16.
18. A photovoltaic system characterized by, A photovoltaic module comprising the solar cell of claim 17.