Slice cell and solar cell module

Abstract

The utility model relates to the field of solar cells, in particular to a slice cell and a solar cell module, and aims to solve the problem that an existing slice cell is poor in damp-heat resistance. In order to achieve the purpose, the slice battery provided by the utility model comprises end parts adjacent to the front surface and the back surface of the slice battery, at least one end part is a fracture surface, a fracture surface passivation layer and a protective film layer are sequentially arranged on the fracture surface, and the protective film layer at least covers the fracture surface passivation layer. The protection film layer covering the section passivation layer is formed on the section passivation layer of the slice battery, so that the section passivation layer is protected, the possibility that the section passivation layer is in contact with water vapor or acidic substances is reduced, the possibility that the section passivation layer is corroded is reduced, and the damp and heat resistance of the slice battery is improved.

Description

Technical Field

[0001] The present disclosure relates to the field of solar cells, and specifically provides a sliced cell and a solar cell module. Background Art

[0002] The core technology of the photovoltaic industry lies in solar cell wafers. The photoelectric conversion efficiency of solar cells and the power of solar cell modules are the most core technical indicators. However, there are many technical obstacles in the solutions for improving the efficiency of solar cells, such as the risk of damp heat failure. Especially for sliced cells, due to the existence of sliced cross-sections, the risk of damp heat failure will increase after long-term use.

[0003] Therefore, there is an urgent need for a sliced cell and a solar cell module to solve the problem of the weak damp heat resistance of current sliced cells. Summary of the Invention

[0004] The present disclosure aims to solve the problems of the prior art and provides a sliced cell and a solar cell module.

[0005] In a first aspect, the present disclosure provides a sliced cell, including: at least one end adjacent to the front and back of the sliced cell is a cross-section, and a cross-section passivation layer and a protective film layer are sequentially arranged on the cross-section, and the protective film layer covers at least the cross-section passivation layer.

[0006] In some exemplary embodiments, fine grid electrodes and main grid electrodes are arranged on the front and / or back of the sliced cell, and the protective film layer also covers the fine grid electrodes.

[0007] In some exemplary embodiments, the protective film layer covering the fine grid electrodes and the cross-section is continuous.

[0008] In some exemplary embodiments, the protective film layer also covers the main grid electrodes.

[0009] In some exemplary embodiments, the protective film layer covering the fine grid electrodes, the main grid electrodes and the cross-section is continuous.

[0010] In some exemplary embodiments, the protective film layer includes at least one layer, and the material of each layer of the protective film layer is one of silicon carbide, silicon nitride, magnesium fluoride, titanium oxide and PVDF.

[0011] In a second aspect, the present disclosure provides a solar cell module, including solar cell wafers, and the solar cell wafers are formed by laying out an array of the above-mentioned sliced cells.

[0012] In some exemplary embodiments, a second protective film layer is laid out on one side or both sides of the whole layer of the solar cell module.

[0013] In some exemplary embodiments, the gap between the sliced cells is filled with a connecting adhesive.

[0014] In some exemplary embodiments, the single-sided or double-sided entire layer of the solar cell module is laid with an encapsulation film layer.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The sliced cell provided by the present disclosure includes ends adjacent to the front and back surfaces of the sliced cell. At least one end is a cross-section, and a cross-section passivation layer and a protective film layer are sequentially arranged on the cross-section. The protective film layer covers at least the cross-section passivation layer. A protective film layer covering the cross-section passivation layer is formed on the cross-section passivation layer of the sliced cell, thereby protecting the cross-section passivation layer and reducing the possibility of the cross-section passivation layer contacting with water vapor or acidic substances, so as to reduce the possibility of the cross-section passivation layer being corroded, thereby improving the ability of the sliced cell to resist damp heat.

[0017] Furthermore, the protective film layer simultaneously covers the fine grid electrodes, thereby protecting the fine grid electrodes and reducing the possibility that the residual soldering flux in the fine grid electrodes reacts with the external water vapor to generate acidic substances, so as to reduce the possibility of the fine grid electrodes being corroded, thereby improving the ability of the sliced cell to resist damp heat. Description of the Drawings

[0018] The following describes the preferred embodiments of the present disclosure with reference to the drawings, in which:

[0019] Figure 1 is a cross-sectional view of a sliced cell provided by the present disclosure;

[0020] Figure 2 is another cross-sectional view of a sliced cell provided by the present disclosure;

[0021] Figure 3 is yet another cross-sectional view of a sliced cell provided by the present disclosure;

[0022] Figure 4 is a cross-sectional view of a solar cell module provided by the present disclosure;

[0023] Figure 5 is another cross-sectional view of a solar cell module provided by the present disclosure;

[0024] Figure 6 is yet another cross-sectional view of a solar cell module provided by the present disclosure.

[0025] Description of the Reference Numerals:

[0026] 1. Slice battery; 2. Fine grid electrode; 3. Main grid electrode; 4. Cross-section passivation layer; 5. Protective film layer; 6. Encapsulation film layer; 7. Second protective film layer; 8. Connecting adhesive. Detailed implementation manners

[0027] The preferred implementation manners of the present disclosure will be described below with reference to the accompanying drawings. Those skilled in the art should understand that these implementation manners are only used to explain the technical principle of the present disclosure and are not intended to limit the protection scope of the present disclosure.

[0028] It should be noted that in the description of the present disclosure, the terms indicating directions or positional relationships such as "upper", "lower", "left", "right", "inner", "outer", etc. are based on the directions or positional relationships shown in the accompanying drawings. This is only for convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present disclosure. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0029] In addition, it should also be noted that in the description of the present disclosure, unless otherwise clearly specified and limited, the terms "installation", "setting", "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, indirectly connected through an intermediate medium, or the communication inside two elements. For those skilled in the art, the specific meanings of the above terms in the present disclosure can be understood according to specific situations.

[0030] At present, some solar cells need to be sliced into required sizes after preparation. A passivation layer (such as alumina) is formed at the cross-section of the sliced battery formed after slicing to protect the sliced cross-section of the sliced battery, and at the same time, it can also reduce the recombination loss at the sliced cross-section of the sliced battery.

[0031] The sliced battery arrays are laid out for series and parallel connection to form a solar cell slice, and the solar cell slice is fixed and encapsulated to form a solar cell module.

[0032] The raw material used for encapsulating the solar cell module is EVA (ethylene-vinyl acetate copolymer), which has excellent flexibility, impact resistance, elasticity, optical transparency, low-temperature flexibility, adhesiveness, environmental stress cracking resistance, weather resistance, corrosion resistance, heat sealing property, and electrical properties, etc. EVA is wrapped on the outer surface of the solar cell slice to encapsulate the solar cell slice, thereby playing a protective role.

[0033] When a solar cell module is placed in a high-temperature and high-humidity environment for a long time or is aged after long-term use, the EVA is prone to decompose and release acetic acid, which is likely to damage the passivation layer at the sliced surface. At the same time, there will also be residues of the soldering flux used in the process of forming the electrodes. As the sliced cells are used for a long time, the soldering flux will also react to form acidic substances, thereby damaging the passivation layer at the sliced surface. In addition, the passivation layer at the sliced surface uses alumina, which is prone to oxidation and failure when used in a high-temperature and high-humidity environment.

[0034] In view of this, an embodiment of the present disclosure provides a sliced cell, including: ends adjacent to the front and back surfaces of the sliced cell, at least one of the ends being a sliced surface, on which a sectional passivation layer and a protective film layer are sequentially arranged, and the protective film layer covers at least the sectional passivation layer.

[0035] Figure 1 It is a sectional schematic diagram of a sliced cell provided by the present disclosure.

[0036] As Figure 1 shown, the sliced cell 1 can be a crystalline silicon cell, which is processed from a semiconductor silicon wafer. Crystalline silicon cells are mainly divided into P-type and N-type, the difference being the doping type of the substrate of the sliced cell 1. At present, the N-type sliced cell 1 can achieve a higher photoelectric conversion efficiency, including PERC (Passivated Emitter Rear Cell), TOPCon (Tunnel Oxide Passivated Contact) cells, HJT (Hereto-junction with Intrinsic Thin-layer) cells, and IBC (Interdigitated BackContact) cells, etc. Of course, the sliced cell 1 involved in the present disclosure is applicable not only to the N-type sliced cell 1 but also to the P-type sliced cell 1.

[0037] The sliced cell 1 includes a front surface (i.e., the sun-facing surface), a back surface (i.e., the sun-shaded surface), and ends adjacent to the front and back surfaces. For some types of sliced cells 1 (such as PERC cells, TOPCon cells, and HJT cells, etc.), fine grid electrodes 2 and main grid electrodes 3 are provided on both the front and back surfaces, and for some other types of sliced cells 1 (such as IBC cells), fine grid electrodes 2 and main grid electrodes 3 are provided on the back surface.

[0038] The sliced battery 1 is generally formed by laser cutting a solar cell, thereby ensuring the production efficiency of the sliced battery 1. Therefore, at least one end of the sliced battery 1 is a cross-section (i.e., the cutting surface), a cross-section passivation layer 4 is provided on the cross-section, and a protective film layer 5 is provided on the cross-section passivation layer 4. The cross-section passivation layer 4 can achieve insulation of the sliced battery 1 at the cross-section, thereby reducing the recombination loss of the sliced battery 1 at the cross-section. The protective film layer 5 can isolate the cross-section passivation layer 4, preventing water vapor and acidic substances in the external environment from contacting the cross-section passivation layer 4, thereby reducing the possibility of damage to the cross-section passivation layer 4 and enhancing the moisture and heat resistance of the sliced battery 1.

[0039] The cross-section passivation layer 4 can be alumina, magnesium fluoride, etc. The protective film layer 5 includes at least one layer, that is, the protective film layer 5 can be a single-layer structure or a multi-layer structure, and the material of each protective film layer 5 is one of silicon carbide, silicon nitride, magnesium fluoride, titanium oxide, and PVDF (polyvinylidene difluoride). Among them, when the protective film layer 5 is silicon carbide, silicon nitride, or magnesium fluoride, it can be formed by chemical vapor deposition; when the protective film layer 5 is PVDF, it can be formed by coating and then drying.

[0040] Figure 2 It is another cross-sectional schematic diagram of the sliced battery provided by the present disclosure.

[0041] In some examples, the protective film layer 5 also covers the fine grid electrode 2. The protective film layer 5 covering the fine grid electrode 2 and the protective film layer 5 covering the cross-section passivation layer 4 can also be discontinuously provided. Of course, as Figure 2 shown, the protective film layer 5 covering the fine grid electrode 2 and the protective film layer 5 covering the cross-section passivation layer 4 can be continuously provided to facilitate the formation of the protective film layer 5. In this way, the protective film layer 5 can protect both the cross-section passivation layer 4 and the fine grid electrode 2 at the same time, enhancing the moisture and heat resistance of the sliced battery 1.

[0042] Figure 3 It is yet another cross-sectional schematic diagram of the sliced battery provided by the present disclosure.

[0043] In other examples, as Figure 3As shown, the protective film layer 5 also covers the fine grid electrode 2 and the main grid electrode 3. The protective film layer 5 covering the fine grid electrode 2, the main grid electrode 3, and the cross-section passivation layer 4 can be continuously arranged to facilitate the formation of the protective film layer 5. Of course, the protective film layer 5 covering the fine grid electrode 2, the main grid electrode 3, and the cross-section passivation layer 4 can also be discontinuously arranged. In this way, the protective film layer 5 can protect the cross-section passivation layer 4, the fine grid electrode 2, and the main grid electrode 3 at the same time, improving the ability of the sliced battery 1 to resist humidity and heat. The main grid electrode 3 is externally connected with a solder strip. After the main grid electrode 3 is covered by the protective film layer 5, the protective film layer 5 at the welding place can be corroded and damaged during the welding process of the solder strip and the main grid electrode 3, realizing the electrical connection between the solder strip and the main grid electrode 3.

[0044] Regarding the setting and formation method of the protective film layer 5, the present disclosure specifically provides three examples of solar cell modules. Among them, fine grid electrodes 2 and main grid electrodes 3 are arranged on both the front and back surfaces of the sliced battery 1, the main grid electrode 3 is located between the fine grid electrodes 2, and one end of the sliced battery 1 is a cross-section.

[0045] In the first example, as Figure 1 shown, the protective film layer 5 covers the fine grid electrodes 2 on the front and back surfaces and the cross-section passivation layer 4, and the protective film layer 5 covering the fine grid electrode 2 and the cross-section passivation layer 4 is discontinuous. Among them, the protective film layer 5 is a metal oxide such as titanium oxide, which has good water-repellent properties, avoiding water vapor or acidic substances, etc. from corroding the cross-section passivation layer 4 and the fine grid electrode 2 through the protective film layer 5, so as to improve the ability of the sliced battery 1 to resist humidity and heat. The protective film layer 5 made of metal oxide can be formed by transfer printing or printing. In this example, the protective film layer 5 does not cover the main grid electrode 3 to facilitate the welding of the main grid electrode 3 with the externally connected solder strip.

[0046] In the second example, as Figure 2 shown, the protective film layer 5 covers the fine grid electrodes 2 on the front and back surfaces and the end of the sliced battery 1, and the protective film layer 5 covering the end of the sliced battery 1 and the fine grid electrode 2 close to this end is continuous. The protective film layer 5 is an organic material or an inorganic material, such as silicon carbide, silicon nitride, magnesium fluoride, etc., which has good hydrophobic properties, avoiding water vapor or acidic substances, etc. from corroding the cross-section passivation layer 4 and the fine grid electrode 2 through the protective film layer 5, so as to improve the ability of the sliced battery 1 to resist humidity and heat. The protective film layer 5 can mask the non-selected areas (such as the main grid electrode 3) through a masking process, and deposit the protective film layer 5 in the selected areas (such as the other areas except the main grid on the front and back surfaces and the end). Taking the protective film layer 5 of silicon carbide as an example, silicon carbide protective film layer 5 can be deposited by using silane and methane, or by magnetron sputtering to impact a silicon carbide target to deposit and form the silicon carbide protective film layer 5. In this example, the protective film layer 5 does not cover the main grid electrode 3 to facilitate the welding of the main grid electrode 3 with the externally connected solder strip.

[0047] It should be noted that when the protective film layer 5 is made of silicon carbide, silicon nitride or magnesium fluoride, it can be formed by chemical vapor deposition. At this time, the thickness of the protective film layer 5 on the fine grid electrode 2 and the cross-section passivation layer 4 is substantially the same.

[0048] In the third example, as Figure 3 shown, the protective film layer 5 covers the fine grid electrodes 2 and the main grid electrodes 3 on the front and back, and the ends of the sliced battery 1, and the protective film layer 5 covering the fine grid electrodes 2, the main grid electrodes 3 and the ends of the sliced battery 1 is continuous, that is, it completely wraps the sliced battery 1. The material of the protective film layer 5 is PVDF and is formed on the sliced battery 1 by coating. The protective film layer 5 on the cross-section passivation layer 4 can be slightly thicker than the protective film layer 5 on the remaining parts (such as the fine grid electrode 2 and the main grid electrode 3), and of course, the thickness can also be substantially the same. The PVDF protective film layer 5 has good weather resistance and can prevent water and acid to protect the fine grid electrode 2, the main grid electrode 3 and the cross-section passivation layer 4. In this example, the protective film layer 5 covers the main grid electrode 3, and during the welding process of the solder strip to the main grid electrode 3, the protective film layer 5 at the welding place can be corroded and damaged to achieve the electrical connection between the solder strip and the main grid electrode 3.

[0049] The end of the sliced battery 1 shown in the above examples only includes one cross-section, but this is not a specific limitation of the present disclosure. Without departing from the principle of the present disclosure, the sliced battery 1 can include two or more cross-sections.

[0050] In summary, the advantages of the sliced battery 1 provided by the present disclosure are as follows:

[0051] (1) A protective film layer 5 covering the cross-section passivation layer 4 is formed on the cross-section passivation layer 4 of the sliced battery 1 to protect the cross-section passivation layer 4, reduce the possibility of the cross-section passivation layer 4 coming into contact with water vapor or acidic substances, thereby reducing the possibility of the cross-section passivation layer 4 being corroded, and thus improving the ability of the sliced battery 1 to resist humidity and heat;

[0052] (2) The protective film layer 5 also covers the fine grid electrode 2 to protect the fine grid electrode 2, reduce the possibility of the residual flux in the fine grid electrode 2 reacting with the external water vapor to generate acidic substances, thereby reducing the possibility of the fine grid electrode 2 being corroded, and thus improving the ability of the sliced battery 1 to resist humidity and heat.

[0053] The sliced battery 1 arrays are laid out in series and parallel to form solar cell wafers, and the solar cell wafers are fixed and encapsulated to form solar cell modules.

[0054] Figure 4 It is a cross-sectional view of a solar cell module provided by the present disclosure.

[0055] As Figure 4As shown, the present disclosure also provides a solar cell module, including a plurality of sliced cells 1. The plurality of sliced cells 1 are arranged in an array, and after being connected in series / parallel and encapsulated by an encapsulation film layer 6, a solar cell module is formed. Among them, the entire encapsulation film layer 6 is laid on one side or both sides of the solar cell module. The present disclosure mainly uses a protective film layer 5 for waterproofing and acid resistance, so the performance requirements of the encapsulation film layer 6 for waterproofing and acid resistance can be reduced. The encapsulation film layer 6 can use materials with slightly weaker performance, which can reduce costs while ensuring the protection performance of the solar cell module.

[0056] Figure 5 It is another cross-sectional schematic diagram of the solar cell module provided by the present disclosure.

[0057] In some examples, as Figure 5 shown, the protective film layer 5 is only provided on the surface of the sliced cell 1 to protect the cross-sectional passivation layer 4. For example, a connecting adhesive 8 is filled in the gap between the sliced cells 1, and then the encapsulation film layer 6 is laid on one side or both sides of the sliced cells 1 arranged in an array.

[0058] Figure 6 It is yet another cross-sectional schematic diagram of the solar cell module provided by the present disclosure.

[0059] In other examples, as Figure 6 shown, after the sliced cells 1 are arranged in an array, a second protective film layer 7 is laid on one side or both sides of the solar cell module to protect the fine grid electrodes 2 and main grid electrodes 3 of the sliced cells 1. For example, the material of the second protective film layer 7 is an organic material with good hydrophobic properties such as PVDF. Then, the encapsulation film layer 6 can be selectively laid on one side or both sides of the solar cell module.

[0060] The encapsulation film layer 6 can be EVA or POE (Polyolefin elastomer).

[0061] There are also the following points to note:

[0062] (1) The drawings of the embodiments of the present disclosure only relate to the structures involved in the embodiments of the present disclosure, and other structures can refer to the general design.

[0063] (2) For clarity, in the drawings used to describe the embodiments of the present disclosure, the thickness of layers or regions is enlarged or reduced, that is, these drawings are not drawn to actual scale. It can be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "under" another element, the element can be "directly" on or under the other element or there can be intermediate elements.

[0064] (3) Without conflict, the embodiments of the present disclosure and the features in the embodiments may be combined with each other to obtain new embodiments.

[0065] As described above, it is only the specific implementation manner of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present disclosure can easily think of changes or substitutions, which should be covered within the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.

Claims

1. A sliced battery, characterized in that, Comprising: Ends adjacent to the front and back surfaces of the sliced cell, at least one of the ends being a cross-section, on which a cross-section passivation layer and a protective film layer are sequentially provided, and the protective film layer covers at least the cross-section passivation layer; Fine grid electrodes and main grid electrodes are provided on the front and / or back surface of the sliced cell, and the protective film layer also covers the fine grid electrodes.

2. The sliced battery according to claim 1, wherein The protective film layer covering the fine grid electrodes and the cross-section is continuous.

3. The sliced battery according to claim 1, wherein The protective film layer also covers the main grid electrodes.

4. The sliced battery according to claim 3, wherein, The protective film layer covering the fine grid electrodes, the main grid electrodes and the cross-section is continuous.

5. The sliced battery according to any one of claims 1 to 4, characterized in that, The protective film layer comprises at least one layer, and the material of each layer of the protective film layer is one of silicon carbide, silicon nitride, magnesium fluoride, titanium oxide and PVDF.

6. A solar cell module, characterized in that, Comprising a solar cell sheet, which is formed by laying out a sliced cell array as described in any one of claims 1 to 5.

7. The solar cell module according to claim 6, wherein A second protective film layer is laid on the whole layer of one side or both sides of the solar cell module.

8. The solar cell module according to claim 6, wherein, The gaps between the sliced cells are filled with connecting glue.

9. The solar cell module according to any one of claims 6 to 8, characterized in that, An encapsulation film layer is laid on the whole layer of one side or both sides of the solar cell module.

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