Photovoltaic module and photovoltaic system

Abstract

The invention provides a photovoltaic module and a photovoltaic system, and belongs to the technical field of photovoltaics. The photovoltaic module comprises a battery body; a plurality of collector electrodes on at least one surface of the battery body; the plurality of current collection electrodes are arranged at intervals in a first direction and extend along a second direction intersected with the first direction; the electric connecting wire extends in the first direction, and the electric connecting wire is fixedly and electrically connected with the current collecting electrode through a connecting part on the current collecting electrode; and a waterproof portion covering a portion of the collector electrode other than the connection portion.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular to a photovoltaic component and a photovoltaic system. Background Art

[0002] With the development of solar cell technology and its wide application, photovoltaic power generation has become one of the more competitive forms of energy in the future. Solar cells are divided into many types based on different cell structures, such as Passivated Emitter and Rear Cell (PERC) cells, Tunnel Oxide Passivated Contact (TOPCon) cells, Heterojunction with Intrinsic Thin-layer (HJT) cells, Interdigitated Back Contacted (IBC) cells, etc.

[0003] In related technologies, metal electrodes are often made on the surface of the above-mentioned solar cells by screen printing, evaporation, electroplating, etc. During the service life of the photovoltaic modules, some metal ions or organic matter in the metal slurry are easily diffused into the interior of the battery, causing the battery performance to decline or even fail. Summary of the invention

[0004] In view of this, in order to at least partially solve at least one of the above-mentioned technical problems, the present application provides a photovoltaic component and a photovoltaic system.

[0005] According to an embodiment of one aspect of the present application, a photovoltaic module is provided, including: a battery body; a plurality of collecting electrodes, located on at least one surface of the battery body; the plurality of collecting electrodes are arranged at intervals in a first direction and extend along a second direction intersecting the first direction; an electrical connection line, extending along the first direction, the electrical connection line is fixedly electrically connected to the collecting electrode through a connecting portion on the collecting electrode; and a waterproof portion, covering a portion other than the connecting portion on the collecting electrode.

[0006] According to another embodiment of the present application, a photovoltaic system is provided, including the photovoltaic assembly as described above.

[0007] According to the photovoltaic module provided by the above-mentioned embodiment of the present application, by covering the waterproof part on the part other than the connecting part of the collecting electrode, the diffusion of smaller metal ions and organic matter in the metal paste into the interior of the battery body driven by water vapor can be reduced, the adverse effect on the passivation of the doping layer of the battery body can be reduced, the risk of passivation failure of the doping layer can be reduced, and the current transmission efficiency of the photovoltaic module can be ensured. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The above and other objects, features and advantages of the present application will become more apparent through the following description of the embodiments of the present application with reference to the accompanying drawings, in which:

[0009] Figure 1 A partial top view of a back contact battery in the related art is shown;

[0010] Figure 2 A partial top view of a photovoltaic module composed of back-contact cells according to an embodiment of the present application is shown;

[0011] Figure 3 A partial top view of a photovoltaic module composed of bifacial cells according to an embodiment of the present application is shown;

[0012] Figure 4 A partial top view of a photovoltaic assembly according to an embodiment of the present application is shown;

[0013] Figure 5 A partial top view of a photovoltaic assembly according to another embodiment of the present application is shown;

[0014] Figure 6 A partial cross-sectional view of a photovoltaic module according to an embodiment of the present application is shown.

[0015] In the drawings, the meanings of the reference numerals are as follows:

[0016] 1. Battery body;

[0017] 2. Collecting electrode;

[0018] 21. Positive collector electrode;

[0019] 22. Negative collector electrode;

[0020] 3. Waterproofing department;

[0021] 31. The first waterproof part;

[0022] 311, waterproof block;

[0023] 32. Second waterproof part;

[0024] 4. Electrical connection wire;

[0025] 5. Disconnection unit;

[0026] W1, width of the first waterproof portion along the first direction;

[0027] W2, width of the second waterproof portion along the first direction;

[0028] W21, width of the second waterproof portion covering the negative collector electrode along the first direction;

[0029] W22, width of the second waterproof portion covering the positive collector electrode along the first direction;

[0030] W3, the length of the waterproof block along the second direction;

[0031] W4, the length of the disconnected portion along the second direction; and

[0032] H. Thickness of the first waterproof portion. DETAILED DESCRIPTION

[0033] Below, embodiments of the present application will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present application. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present application. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present application.

[0034] The terms used herein are only for describing specific embodiments and are not intended to limit the present application. The term "comprising" used herein indicates the existence of features, steps, operations, but does not exclude the existence or addition of one or more other features.

[0035] In the case of using expressions such as "at least one of A, B, and C, etc.", it should generally be interpreted in accordance with the meaning of the expression generally understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.). In the case of using expressions such as "at least one of A, B, or C, etc.", it should generally be interpreted in accordance with the meaning of the expression generally understood by those skilled in the art (for example, "a system having at least one of A, B, or C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0036] In the related art, solar cells, such as back-contact cells, have no grid lines on the front side, and the positive and negative electrodes are concentrated on the back side of the battery, showing a cross-finger shape. Another example is a double-sided battery with electrodes on both the front and back sides. Trace metal ions or organic matter in the electrodes on the surface of the cell will diffuse into the interior of the battery with the diffusion of water vapor, causing the performance of the cell to deteriorate. In severe cases, it may passivate and fail, affecting the collection of current. In addition, if the positive and negative electrodes come into contact with conductive foreign matter, causing the positive and negative electrodes to be connected, a short circuit will occur, which will have a significant impact on a single cell or even the entire photovoltaic module.

[0037] Figure 1 A partial top view of a back contact battery in the related art is shown. Figure 1 As shown, the collector electrode is in an exposed state. When water vapor contacts the exposed electrode, it is not only easy for trace metal ions or organic matter to enter, causing abnormal battery passivation, but also if conductive foreign matter is encountered, it is easy for the positive and negative electrodes of the battery to be conductive, forming a composite area, resulting in more serious defects in the battery cell.

[0038] Therefore, in the process of realizing the concept of this application, it was found that by covering the portion other than the connecting portion on the collecting electrode with a waterproof part, the diffusion of trace metal ions and organic matter into the interlayer of the battery cell under the action of water vapor is reduced, thereby avoiding the passivation failure of the battery cell and improving the stability of the photovoltaic module.

[0039] Specifically, according to an embodiment of one aspect of the present application, a photovoltaic assembly is provided. Figure 2 A partial top view of a photovoltaic module composed of back-contact cells according to an embodiment of the present application is shown. Figure 3 FIG. 1 shows a partial top view of a photovoltaic module composed of bifacial cells according to an embodiment of the present application. Figure 2~Figure 3 As shown, the photovoltaic module includes: a battery body 1, a plurality of collector electrodes 2, a waterproof part 3, and an electrical connection line 4. The plurality of collector electrodes 2 are located on at least one surface of the battery body 1; the collector electrodes 2 (also called fine grids, collector grid lines, auxiliary grids, etc.) are arranged along a first direction (such as Figure 2 The upper and lower directions shown in the figure are arranged at intervals, and along a second direction (such as Figure 2 or Figure 3 The electrical connection line 4 is arranged on the surface and extends along the first direction. The electrical connection line 4 can also be called a welding strip or an interconnection strip, which is used to connect at least two solar cells in series. The electrical connection line 4 is fixedly electrically connected to the collector electrode 2 through a connecting portion (not shown in the figure) on the collector electrode 2. The connecting portion can be a portion on the collector electrode 2 for conductive interconnection, or a structure such as a thickened section or a pad on the collector electrode 2 that is welded to the welding strip. That is, the connecting portion is a portion on the collector electrode 2 that intersects with the welding strip and is fixedly conductive. The portion on the collector electrode 2 that intersects with the welding strip but is not fixedly conductively connected does not belong to the connecting portion. Of course, a main grid and an auxiliary welding layer can also be arranged between the connecting portion and the electrical connection line 4. The auxiliary welding layer can be, for example, solder, solder paste, such as solder, which is used to weld the collector electrode 2 and the welding strip; it can also be a conductive adhesive layer, such as conductive silver paste, conductive glue, etc., which is used to conductively connect the auxiliary grid and the welding strip. The waterproof portion 3 covers the portion other than the connecting portion on the collector electrode 2.

[0040] According to the embodiments of the present application, the photovoltaic module of the present application can be a photovoltaic module composed of bifacial cells, such as an HJT photovoltaic module (a module composed of heterojunction cells), a TOPCon photovoltaic module (a module composed of tunneling oxide passivation contact cells), or a Figure 2 The photovoltaic module composed of back contact cells shown. Furthermore, the photovoltaic module composed of back contact cells can be a traditional IBC photovoltaic module (a module composed of interdigitated back contact cells), or a TBC photovoltaic module (a module composed of TOPCon back contact cells), an HBC photovoltaic module (a module composed of heterojunction back contact cells) or a hybrid photovoltaic module (i.e., the PN passivation therein is a different passivation material, for example, it can be a combination of polycrystalline silicon passivation and amorphous / microcrystalline passivation).

[0041] The photovoltaic module comprises a cell body 1, which at least comprises a substrate and a doping layer on the substrate, wherein the substrate is a rectangular or square structure.

[0042] The cell body 1 of the above HJT photovoltaic module has a first surface and a second surface arranged opposite to each other, the first surface can be a backlight surface, and the second surface can be a light-receiving surface. The doping layer includes an n-doping region and a p-doping region. The n-doping region is located on the first surface, and the p-doping region is located on the second surface. The two can also be interchanged as needed, and are not particularly limited here.

[0043] The cell body 1 of the TOPCon photovoltaic module has a first surface and a second surface arranged opposite to each other, the first surface can be a backlight surface, and the second surface can be a light-receiving surface. The doping layer includes an n-doping region and a p-doping region. The n-doping region is located on the first surface, and the p-doping region is located in the second surface. The two can also be interchanged as needed, and are not particularly limited here.

[0044] The cell body 1 of the above IBC photovoltaic module comprises n-doped regions and p-doped regions arranged alternately and spaced along a first direction on a substrate to form an interdigitated doping structure. The n-doped regions and p-doped regions are respectively provided with spaced electrode structures.

[0045] The cell body 1 of the above-mentioned TBC photovoltaic module includes a tunneling oxide layer arranged on a substrate, and an n-doped region and a p-doped region formed by a doped polysilicon layer. Among them, the TOPCon structure formed by the stacked tunneling oxide layer and the doped polysilicon layer can provide a higher carrier lifetime and lower surface recombination for the TBC photovoltaic module than the IBC photovoltaic module, which is conducive to improving the photoelectric conversion efficiency of the TBC photovoltaic module.

[0046] The cell body 1 of the above-mentioned HBC photovoltaic module includes an n-doped region and a p-doped region arranged on a substrate to form a heterojunction structure. Among them, the n-doped region includes but is not limited to microcrystalline silicon or amorphous silicon (to provide electrons), and the p-doped region can also use microcrystalline silicon or amorphous silicon (such as using boron as a dopant to provide holes). HBC photovoltaic modules help to improve the carrier lifetime and reduce surface recombination. Furthermore, a transparent conductive oxide layer (i.e., TCO) can be set between the surface of the n-doped region and the p-doped region and the electrode, which is beneficial to collect carriers in the doped region and can also play a certain anti-reflection role.

[0047] The cell body 1 of the hybrid photovoltaic module may adopt a layer structure similar to that of an IBC cell or a TBC cell, and configure a corresponding passivation layer structure thereon, such as a combination of at least two of polycrystalline silicon passivation, amorphous silicon passivation and microcrystalline silicon passivation.

[0048] The main material of the doped layer can be selected from silicon (Si), germanium (Ge), silicon carbide (SiC x ) or gallium arsenide (GaAs) and other semiconductor materials, which can be amorphous, microcrystalline, single crystal, nanocrystalline or polycrystalline. By introducing donor impurities such as phosphorus (P), arsenic (As) or antimony (Sb) into the aforementioned semiconductor materials, an n-doped region is obtained; by introducing acceptor impurities such as boron (B), aluminum (Al) or gallium (Ga) into the aforementioned semiconductor materials, a p-doped region is obtained.

[0049] The first surface of the cell body 1 of the photovoltaic module composed of the above-mentioned back-contact cells has an A region and a B region arranged alternately along a first direction, and an isolation region (also called a Gap region) located between the A region and the B region. The n-doped region of the above-mentioned doping layer is located on the A region, and the p-doped region is located on the B region. Of course, the two can also be interchangeable, and no special limitation is made here. The isolation region is used to separate the n-doped region and the p-doped region from each other at the boundary to prevent short circuits, and can also prevent direct contact between the n-doped region and the p-doped region materials.

[0050] Optionally, the collector electrode 2 can be formed by printing, physical vapor deposition, electrodeposition and other processes. Further, optionally, printing can be, for example, screen printing, inkjet printing, laser transfer, etc. The following is an exemplary illustration of the process of preparing the collector electrode 2 by screen printing: preparing a metal slurry containing metal powder; using a screen template with a specific pattern, the template is used to define the position and shape of the collector electrode 2; stamping the metal slurry onto the battery surface through the screen template to form a patterned structure of the collector electrode 2; removing the dissolved in the metal slurry by heating and drying, and then performing high-temperature sintering to achieve good contact between the collector electrode 2 and the battery body 1.

[0051] According to the embodiment of the present application, by covering the portion other than the connection portion on the collector electrode 2 with the waterproof portion 3, the diffusion of smaller metal ions and organic matter in the metal slurry into the interior of the battery body 1 driven by water vapor can be reduced. On the one hand, it can reduce the entry of smaller metal ions into the battery body (especially the Gap area of ​​the back contact battery) to form a recombination center, and can also reduce the adverse effects on the passivation of the p-doped area and / or the n-doped area, reduce the failure risk of the p-doped area and the n-doped area, and ensure the current transmission efficiency of the photovoltaic module. On the other hand, by providing the waterproof portion 3, it can reduce the acidic organic matter or alkaline organic matter in the metal slurry from entering the p-doped area and the n-doped area under the transportation of water vapor, avoid etching of the p-doped area and / or the n-doped area, and further reduce the failure risk of the p-doped area and / or the n-doped area, and ensure the current transmission efficiency and long-term operation stability of the photovoltaic module.

[0052] It should be noted that the cell body 1 of the photovoltaic module may include a passivation layer located between the substrate and the doping layer as required. The passivation layer can be understood as being used to reduce the defect states of capturing and recombining photogenerated carriers (i.e., electron-hole pairs), reduce the defect density, thereby reducing the recombination of electrons and holes, and improving the photoelectric conversion efficiency. The material of the passivation layer may include silicon oxide, silicon nitride, aluminum oxide, etc. The passivation layer may be a single layer or a multi-layer stacked structure. The passivation layer may be, for example, an intrinsic amorphous silicon layer (a-Si:H) or a tunneling oxide layer.

[0053] By covering the portion other than the connecting portion on the collector electrode 2 with the waterproof portion 3, etching of the passivation layer by metal ions and / or organic matter is avoided, failure of the photovoltaic module is avoided, the photoelectric conversion efficiency of the photovoltaic module is guaranteed, and the stability and service life of the photovoltaic module are improved.

[0054] It should be noted that the effective shielding of the electrical connection wire 4 on the collector electrode 2 can prevent water vapor from contacting the electrode, thereby reducing the possibility of water vapor carrying metal ions and / or organic matter penetrating and diffusing into the photovoltaic module. Therefore, the waterproof part 3 covers the above position, and the combination of the electrical connection wire can effectively protect the photovoltaic module from water vapor.

[0055] In some embodiments, more than 71% and less than 98% of the length of the collector electrode 2 along the second direction is covered with the waterproof portion 3, for example, 71%, 75%, 78%, 80%, 85%, 90%, 95% or 98%. Adjusting the length covered by the waterproof portion 3 to the above position helps to enhance the waterproof and vapor-proof effect of the photovoltaic module while taking into account the connection reliability of the electrical connection line.

[0056] Optionally, more than 75% and less than 98% of the length of each collecting electrode 2 along the second direction is covered with a waterproof portion 3, further improving the coverage reliability of the waterproof portion 3 on the collecting electrode 2, and further improving the possibility of blocking water vapor from carrying metal ions and organic matter into the photovoltaic module, thereby extending the service life of the photovoltaic module and improving its stability.

[0057] The specific structural settings of different solar cells will be described in detail below.

[0058] like Figure 2 In the back contact battery shown, the collector electrode 2 includes a positive collector electrode 21 and a negative collector electrode 22. Both the positive collector electrode 21 and the negative collector electrode 22 are located on the back of the battery body 1. It can be understood that the positive collector electrode 21 is arranged on the p-doped region to extract the carriers of the p-doped region; the negative collector electrode 22 is arranged on the n-doped region to extract the carriers of the n-doped region. The waterproof part 3 includes a first waterproof part 31 and a second waterproof part 32. The first waterproof part 31 is located between the electrical connection wires 4, or the first waterproof part 31 is located between the electrical connection wires 4 closest to the edge of the battery and the edge of the battery. The first waterproof part 31 is arranged at the above position, which can achieve a more accurate coverage of the collector electrode 2, build a more reliable barrier, prevent the water vapor from carrying metal ions and / or organic matter in the electrode to penetrate and diffuse into the interior of the photovoltaic module, reduce the risk of water vapor infiltrating the photovoltaic module, and maintain the effective operation of the photovoltaic module. The second waterproof portion 32 is located on the collecting electrode 2. The second waterproof portion 32 is suitable for isolating the collecting electrode 2 from the opposite-sex electrical connection line 4. The second waterproof portion 32 is set at the above-mentioned position. While strengthening the waterproof vapor effect of the overlapping position of the collecting electrode 2 and the opposite-sex electrical connection line 4, it also ensures the insulation between the two, avoids the battery short circuit phenomenon that may occur due to the opposite-sex connection, and improves the stability of the battery.

[0059] like Figure 3 In the double-sided battery shown, the collecting electrode 2 includes a positive collecting electrode 21 and a negative collecting electrode 22, and the positive collecting electrode 21 and the negative collecting electrode 22 are respectively located on the front and back of the battery body 1. For example, the positive collecting electrode 21 can be located on the front of the battery body 1 and the negative collecting electrode 22 can be located on the back of the battery body 1, or the positive collecting electrode 21 can be located on the back of the battery body 1 and the negative collecting electrode 22 can be located on the front of the battery body 1, and no special limitation is made here. Figure 3The schematic diagram shows that the positive collector electrode 21 is located on the front of the battery body, and the waterproof part 3 includes a first waterproof part 31, which is located between the electrical connection wires 4, or between the electrical connection wire 4 closest to the battery edge and the battery edge. By arranging the first waterproof part 31 at the above position, it is also possible to achieve a more accurate coverage of the collector electrode 2, reduce the risk of water vapor penetrating into the interior of the photovoltaic module, and thus block the possibility of tiny metal ions and / or organic matter penetrating and diffusing into the interior of the photovoltaic module.

[0060] In some embodiments, the photovoltaic module may also include: a bus electrode, which is directly in contact and electrically connected to the collector electrode 2 of the same polarity, and is electrically isolated from the collector electrode 2 of a different polarity. The bus electrode can be regarded as a main grid structure connected to the collector electrode 2. The extension direction of the bus electrode intersects with the extension direction of the collector electrode 2, and preferably the extension directions of the two intersect. The connecting portion on the bus electrode or the collector electrode 2 is fixed to and electrically connected to the electrical connection line 4. The fixing here can be welding, conductive bonding, etc. When the connecting portion of the collector electrode 2 is connected to the electrical connection line 4, or the collector electrode 2 is connected to the electrical connection line 4 through the bus electrode, an intermetallic compound (i.e., IMC) is formed at the connection position.

[0061] In an illustrative embodiment, the materials of the collector electrode 2 and the bus electrode include but are not limited to silver, copper, silver-clad copper, and the like.

[0062] In some embodiments, continue to refer to Figure 2 , the solar cell meets at least one of the following conditions: A. The width W1 of the first waterproof portion 31 along the first direction is 1.1 to 1.5 times the width of the collector electrode 2, for example, it can be 1.1 times, 1.2 times, 1.3 times, 1.4 times or 1.5 times. Adjusting W1 within the above range helps to achieve full coverage of the collector electrode 2 in the width direction, and improves the water vapor resistance in the width direction. Local spurs or protrusions will inevitably form on the surface of the collector electrode 2. If the first waterproof portion 31 is too narrow, metal ions and organic matter at the protruding position can easily penetrate the first waterproof portion 31 and migrate to the inside of the battery body 1 under the action of water vapor.

[0063] B. The width W2 of the second waterproof portion 32 along the first direction is 1.3-1.9 times the width of the collector electrode 2, for example, it can be 1.3 times, 1.4 times, 1.5 times, 1.6 times, 1.7 times, 1.8 times or 1.9 times. Adjusting W2 within the above range not only ensures that the second waterproof portion 32 has a good waterproof effect, but also further strengthens the insulation performance of the second waterproof portion 32, avoiding the possibility of electrical connection between the collector electrode 2 and the electrical connection wires of different polarities. For the back contact battery, when the collector electrode 2 is connected to the electrical connection wire 4, solder paste or the like is required to be arranged between the collector electrode 2 and the electrical connection wire 4 to achieve auxiliary welding and improve welding reliability. At this time, during the drying or welding process of auxiliary solder such as solder paste, the metal particles in the auxiliary solder are easily splashed to the nearby area due to high temperature, for example, splashed to the vicinity of the second waterproof portion 32, that is, the position where the collector electrode 2 and the opposite electrical connection wire 4 need to be insulated. And the splashed metal particles are easy to cause short circuit risk. When W2 is set as above, the risk of short circuit caused by splashing metal particles can be reduced to a great extent.

[0064] C. On a collecting electrode 2, the width W1 of the first waterproof portion 31 along the first direction is smaller than the width W2 of the second waterproof portion 32 along the first direction. Setting W2 wider than W1 can reduce the risk of short circuit between the collecting electrode 2 and the electrical connection line 4 under the action of water vapor.

[0065] D. On a collecting electrode 2, the ratio of the width W2 of the second waterproof portion 32 along the first direction to the width W1 of the first waterproof portion 31 along the first direction is (3~25):1, for example, it can be 3:1, 6:1, 9:1, 12:1, 15:1, 18:1, 21:1, 24:1 or 25:1. Adjusting the ratio between the two within the above range can take into account better waterproof effect, better insulation effect and material cost.

[0066] E. The ratio of the width W21 of the second waterproof portion 32 covering the negative collector electrode 22 along the first direction to the width W22 of the second waterproof portion 32 covering the positive collector electrode 21 along the first direction is (35-55): (60-80), for example, it can be 35:60, 40:65, 45:70, 50:75 or 55:80. The main carriers (electrons and holes) in the n-doped region and the p-doped region have different diffusion lengths. Generally speaking, the electron diffusion length in the p-doped region is longer than the hole diffusion length in the n-doped region. Therefore, the collector electrode 2 in the p-doped region is relatively wider, and then W22 is designed to be relatively wider, so as to achieve a better waterproof effect.

[0067] F. The width W1 of the first waterproof portion 31 along the first direction is 28 to 48 μm, for example, 28 μm, 32 μm, 36 μm, 40 μm, 44 μm or 48 μm. Setting W1 within the above range can achieve sufficient coverage of the collecting electrode 2 while avoiding material waste caused by the first waterproof portion being too wide.

[0068] G. The width W2 of the second waterproof portion 32 along the first direction is 420~720μm, for example, it can be 420μm, 450μm, 480μm, 510μm, 540μm, 570μm, 600μm, 630μm, 660μm, 690μm or 720μm. Adjusting W2 within the above range can achieve better waterproof and insulating effects while taking into account material costs.

[0069] In some embodiments, Figure 4 A partial top view of a photovoltaic assembly according to an embodiment of the present application is shown; Figure 5 FIG. 2 shows a partial top view of a photovoltaic module according to another embodiment of the present application. Figure 4~Figure 5 As shown, between two adjacent electrical connection lines 4, the waterproof part 3 includes at least two waterproof blocks 311 along the second direction, and the two adjacent waterproof blocks 311 are disconnected from each other by the disconnection part 5. And / or, between the electrical connection line 4 and the edge of the battery, the waterproof part 3 includes at least two waterproof blocks 311 along the second direction, and the two adjacent waterproof blocks 311 are disconnected from each other by the disconnection part 5. The disconnection part 5 is used to interrupt the waterproof part 3 at different positions, so that in the process of waterproof material preparation, such as printing and subsequent drying, the situation that the battery body 1 is subjected to greater stress and the battery body 1 is severely warped due to excessive wet weight of the entire surface printing is reduced, the stress of the waterproof part 3 can be reduced to a great extent, the warping problem of the battery body 1 can be improved, and then the battery cell cracking and failure can be reduced.

[0070] The waterproof portion 3 includes at least two waterproof blocks 311 along the second direction, for example, there may be 2, 3, 4, 5, 6, etc., which is not particularly limited here.

[0071] It can be understood that the shape of the waterproof block 311 can be, for example, a block or a strip, which is not particularly limited here.

[0072] For example, Figure 4 As shown, the waterproof part 3 includes two waterproof blocks 311 along the second direction. A disconnection part 5 is provided between two adjacent electrical connection lines 4 and between the electrical connection line 4 and the edge of the battery, respectively, which can reduce the warping of the battery body 1 while taking into account the reduction in the amount of waterproof material used, and at the same time provide better water vapor resistance performance and improve the stability of the photovoltaic module.

[0073] like Figure 5As shown, the waterproof part 3 includes three waterproof blocks 311 along the second direction. There are two disconnecting parts 5 between two adjacent electrical connection lines 4 and between the electrical connection line 4 and the edge of the battery, which can further reduce the warping of the battery body 1 on the basis of having one disconnecting part 5, while taking into account the good waterproof performance.

[0074] It should be noted that, in order to enhance the water vapor barrier effect of the waterproof part 3, it is not necessarily the case that the more disconnection parts 5 are provided on the waterproof part 3, the better.

[0075] In some embodiments, the length W4 of the disconnection portion 5 along the second direction is 50-150 μm, such as 50 μm, 75 μm, 100 μm, 125 μm or 150 μm; the sum of the lengths W4 of all disconnection portions 5 on a collector electrode 2 in the second direction is less than or equal to 4000 μm, such as 500 μm, 1000 μm, 1500 μm, 2000 μm, 2500 μm, 3000 μm, 2500 μm or 4000 μm. Adjusting W4 and the sum of W4 on a collector electrode 2 within the above range, for a collector electrode 2, controlling the total length of the disconnection portion 5 while controlling the length of a single disconnection portion 5, the combination of the two can avoid the problem of a single disconnection portion 5 being too long and having a poor waterproof effect, and further ensure a better water vapor barrier effect.

[0076] In some embodiments, the length W4 of the disconnection portion 5 between two adjacent electrical connection lines 4 and / or between the electrical connection line 4 and the edge of the battery along the second direction is 100 μm. The sum of the lengths W4 of all disconnections 5 on a collector electrode 2 in the second direction is greater than 1750 μm and less than 3500 μm, for example, it can be 1750 μm, 2000 μm, 2200 μm, 2400 μm, 2600 μm, 2800 μm, 3250 μm or 3500 μm. Adjusting the two in the above ranges further takes into account the effect of blocking water vapor and reducing stress of the photovoltaic module, and further improves the service life of the photovoltaic module.

[0077] In some embodiments, the length W3 of a waterproof block 311 along the second direction is greater than or equal to 1 mm and less than or equal to 9 mm, for example, it can be 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm or 9 mm; the difference between the thickness of the waterproof block 311 and the thickness of the collector electrode 2 is greater than or equal to 8 μm and less than or equal to 30 μm, for example, it can be 8 μm, 10 μm, 15 μm, 20 μm, 25 μm or 30 μm. If the waterproof block 311 is set too long and too thick, it is easy to bring greater stress during the manufacturing and drying process, resulting in severe warping of the battery cell and causing fragments; if the waterproof block 311 is set too short and too thin, it is difficult to achieve a good effect of blocking water vapor, thereby causing passivation failure and it is difficult to maintain the effective operation of the photovoltaic module. At the same time, when the length W3 of the waterproof block 311 is controlled to be set within the above range, and the thickness of the waterproof block is within the above range, it can be ensured that the waterproof block can play a good role in blocking water vapor and reduce the warping caused by the waterproof block.

[0078] In some embodiments, Figure 6 A partial cross-sectional view of a photovoltaic module of some embodiments is shown, Figure 6 As shown, the thickness H of the first waterproof portion 31 is set to exceed the metal paste by 15 μm, and exceed the metal paste by 5 μm at both ends along the width of the first direction, so that the thickness of the waterproof material can fully cover the top and sides of the collecting electrode 2, avoiding the abnormal phenomenon of missing printing, ensuring a good water vapor blocking effect and taking into account a good insulation function.

[0079] In some embodiments, the photovoltaic module satisfies at least one of the following conditions: the length W3 of the waterproof block 311 along the second direction is the same, so that a waterproof matrix can be formed, the generation of waterproof gaps can be reduced, and multiple waterproof blocks can be better combined to jointly achieve a better water vapor barrier effect, thereby ensuring the stability of the photovoltaic module.

[0080] Along the first direction, the center lines of the plurality of disconnected portions 5 are located on a common straight line or are staggered. Figure 4~Figure 5 In the figure, it is schematically shown that the center line is located on a common straight line. The center line of the breaking portion 5 is located on a common straight line, which facilitates the printing of the waterproof material and improves the convenience of the process. Figure 4~Figure 5 It does not mean a special limitation on the center line of the disconnection portion 5. It can also be arranged in a staggered manner, which helps to disperse the stress and further improve the warping phenomenon of the battery cell.

[0081] In some embodiments, the adjacent first waterproof portion 31 and the second waterproof portion 32 are disconnected from each other by a disconnection portion 5. It should be noted that the disconnection portion 5 here has the same size as the aforementioned disconnection portion 5 and is not described in detail. The adjacent first waterproof portion 31 and the second waterproof portion 32 are disconnected from each other, which further reduces the stress of the battery cell in the process of making the waterproof material and improves the warping problem of the battery cell.

[0082] In some embodiments, the battery body 1 includes a silicon substrate and a transparent conductive layer (TCO layer) located on the surface of the silicon substrate; along the first direction, the width of the first waterproof portion 31 covering the transparent conductive layer is less than the width of the second waterproof portion 32 covering the transparent conductive layer. It should be noted that the width of the second waterproof portion 32 covering the transparent conductive layer is set to be wider, which can prevent the short circuit phenomenon that may occur between the heterogeneous electrical connection line 4 and the TCO layer while preventing water, and accordingly, the first waterproof portion 31 covers the collector electrode 2 with a smaller width, thereby reducing the loss of waterproof portion material.

[0083] In some embodiments, the photovoltaic module includes a first area and a second area (not shown in the figure) located inside the first area. It can be understood that the second area is the central area of ​​the photovoltaic module, the first area surrounds the second area and the edge of the photovoltaic module, and the width of the waterproof part 3 located in the first area is greater than the width of the waterproof part 3 in the second area, thereby strengthening the water vapor blocking effect at the edge of the photovoltaic module and enhancing the battery waterproof effect in the weak area of ​​the module. It should be understood that the width direction here is parallel to the first direction.

[0084] In some embodiments, the battery body 1 includes a main body and an edge portion located outside the main body, and the cross-sectional area of ​​the waterproof portion 3 located at the edge portion is larger than the cross-sectional area of ​​the waterproof portion 3 of the main body, which further enhances the water vapor barrier effect of the edge portion of the battery cell and reduces the possibility of water vapor penetrating into the battery cell. The size of the waterproof portion 3 is divided into zones to enhance the water barrier effect in areas that are easily permeable to water vapor, thereby avoiding failure of the photovoltaic module and increasing the service life of the photovoltaic module.

[0085] In some embodiments, along the second direction, the length of the portion not covered by the waterproof portion 3 and the electrical connection line 4 on a collector electrode 2 accounts for less than 18% of the length of the collector electrode 2, for example, it can be 2%, 4%, 6%, 8%, 10%, 12%, 14%, 16% or 18%. The portion of the collector electrode 2 provided with the waterproof portion 3 and the portion welded with the electrical connection line 4 both have a good water vapor barrier effect. When the two are combined and the length not covered by the two is adjusted to account for less than 18%, the waterproof performance of a collector electrode 2 can be more comprehensively controlled.

[0086] In some embodiments, the collector electrode 2 is continuously distributed along the second direction, which helps to fully collect the current of the corresponding doping area on the battery cell. The material of the collector electrode 2 includes copper, for example, it can be silver-coated copper or copper slurry; the waterproof part 3 uses UV curing glue or thermosetting glue. When using copper slurry, UV curing glue (light curing glue) can be used, which can greatly improve the oxidation problem caused by annealing copper in the air. When using silver-coated copper slurry, due to the silver wrapping, thermosetting glue can be used for annealing in the air, which improves the oxidation problem that may occur in the copper slurry and improves the conductive effect of the collector electrode 2.

[0087] In some embodiments, along the second direction, the distance between the electrical connection line 4 and the adjacent waterproof part 3 is greater than or equal to the length of the disconnection part 5. Here, the distance between the electrical connection line 4 and the adjacent waterproof part 3 mainly refers to the distance between the contour line of the positive projection side edge of the electrical connection line 4 and the end of the waterproof part 3 when viewed from above. Setting the distance between the two within the above range can prevent the waterproof part 3 from extending and invading between the electrical connection line 4 and the collector electrode 2, thereby avoiding the adverse effect of the waterproof part 3 on the electrical connection and ensuring the reliability of the electrical connection of the component.

[0088] In some embodiments, the first cell and the second cell are connected by an electrical connection line 4, specifically, the first cell and the second cell are in series. In the battery string, the electrical connection line 4 connects the positive collector electrode 21 of the adjacent previous cell and the negative collector electrode 22 of the next solar cell to realize the series connection of current. There is a distance between the center line of the disconnection portion 5 on the first cell and the corresponding disconnection portion 5 on the second cell along the second direction, and the distance is less than 1.8 mm. In this way, it can be ensured that the warping deformation positions of the two cells connected by the electrical connection line 4 are consistent, the alignment of the cells is high, and the deviation in the second direction is small. Thereby, the cracks caused by the large difference in deformation of the welding position of the electrical connection line 4 can be reduced, the torsion of the electrical connection line 4 between the cells can be reduced, and the shear force on the electrical connection line 4 between the two cells can be reduced.

[0089] In some embodiments, the waterproof part 3 is disposed on the front and back sides of the battery body 1, and the patterns of the waterproof parts 3 on the front and back sides are the same. If the patterns of the waterproof parts 3 are the same, the same screen can be used for the front and back sides, which can further simplify the process, make the preparation more convenient, and improve practicality.

[0090] In some embodiments, the waterproof part 3 is disposed on the front and back of the battery body 1, and the disconnection parts 5 on the front and back are staggered. Due to the staggered arrangement of the disconnection parts 5, after the waterproof part is printed and dried, the stress on the front and back of the battery cell is more dispersed, thereby improving the warping.

[0091] In some embodiments, the pattern of the waterproof part 3 of each cell included in the photovoltaic module is the same; the pattern of the disconnection part 5 of each cell is the same. Each cell has multiple waterproof parts 3 and multiple disconnection parts 5. The pattern of the waterproof part 3 and the pattern of the disconnection part 5 on each cell are the same, so the same waterproof part 3 pattern screen can be used for production, which can reduce the process difficulty, reduce the process cost, and improve the production efficiency.

[0092] According to another embodiment of the present application, a photovoltaic system is provided, including the photovoltaic assembly as described above.

[0093] According to the embodiments of the present application, by using the above-mentioned photovoltaic components in a photovoltaic system, it helps to reduce the diffusion of trace metal ions and / or organic matter into the interior of the component driven by water vapor, reduce the risk of passivation failure of the component, and ensure the current transmission efficiency of the photovoltaic system and the stability of the overall operation.

[0094] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present application. It should be understood that the above description is only a specific embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A photovoltaic module, characterized in that: include: Battery body; A plurality of current collecting electrodes are located on at least one surface of the battery body; A plurality of collector electrodes are arranged at intervals in a first direction and extend along a second direction intersecting with the first direction; an electrical connection line extending along a first direction, wherein the electrical connection line is fixedly electrically connected to the collector electrode through a connection portion on the collector electrode; and The waterproof part covers the portion other than the connecting portion on the collector electrode.

2. The photovoltaic module according to claim 1, characterized in that: The waterproof portion covers not less than 71% and not more than 98% of the length of the collector electrode along the second direction.

3. The photovoltaic module according to claim 1, characterized in that: The collector electrode includes a positive collector electrode and a negative collector electrode, and the positive collector electrode and the negative collector electrode are both located on the back of the battery body; the waterproof part includes a first waterproof part and a second waterproof part; the first waterproof part is located between the electrical connection wires, or the first waterproof part is located between the electrical connection wires and the edge of the battery; the second waterproof part is located on the collector electrode, and the second waterproof part is suitable for isolating the collector electrode from the opposite-sex electrical connection wires; Or, the collecting electrode includes a positive collecting electrode and a negative collecting electrode, and the positive collecting electrode and the negative collecting electrode are respectively located on the front and back of the battery body; the waterproof part includes a first waterproof part, and the first waterproof part is located between the electrical connecting wires, or between the electrical connecting wires and the edge of the battery.

4. The photovoltaic module according to claim 3, characterized in that: The solar cell meets at least one of the following conditions: A. The width of the first waterproof portion along the first direction is 1.1 to 1.5 times the width of the collector electrode; B. The width of the second waterproof portion along the first direction is 1.3-1.9 times the width of the collector electrode; C. On a collector electrode, the width of the first waterproof portion along the first direction is smaller than the width of the second waterproof portion along the first direction; D. On a collector electrode, the ratio of the width of the second waterproof portion along the first direction to the width of the first waterproof portion along the first direction is (3-25):1; E. The ratio of the width of the second waterproof portion covering the negative collector electrode to the width of the second waterproof portion covering the positive collector electrode along the first direction is (35-55): (60-80); F. The width of the first waterproof portion along the first direction is 28-48 μm; G. The width of the second waterproof portion along the first direction is 420-720 μm.

5. The photovoltaic module according to any one of claims 1 to 4, characterized in that: Between two adjacent electrical connection lines, the waterproof portion includes at least two waterproof blocks along the second direction, and two adjacent waterproof blocks are disconnected from each other by a disconnection portion; And / or, between the electrical connection line and the edge of the battery, the waterproof portion includes at least two waterproof blocks along the second direction, and two adjacent waterproof blocks are disconnected from each other by a disconnecting portion.

6. The photovoltaic module according to claim 5, characterized in that: The length of the waterproof block along the second direction is greater than or equal to 1 mm and less than or equal to 9 mm; the difference between the thickness of the waterproof block and the thickness of the collector electrode is greater than or equal to 8 μm and less than or equal to 30 μm.

7. The photovoltaic module according to claim 5, characterized in that: The length of the disconnected portion along the second direction is 50-150 μm; The total length of all the disconnected portions on the collector electrode in the second direction is less than or equal to 4000 μm.

8. The photovoltaic module according to claim 5, characterized in that: The photovoltaic module meets at least one of the following conditions: The waterproof blocks have the same length along the second direction; Along the first direction, center lines of the plurality of break portions are located on a common straight line or are staggered.

9. The photovoltaic module according to claim 3, characterized in that: The adjacent first waterproof portions and second waterproof portions are disconnected from each other by a disconnection portion.

10. The photovoltaic module according to claim 3, characterized in that: The battery body comprises a silicon substrate and a transparent conductive layer located on the surface of the silicon substrate; Along the first direction, a width of the first waterproof portion covering the transparent conductive layer is smaller than a width of the second waterproof portion covering the transparent conductive layer.

11. The photovoltaic module according to any one of claims 1 to 4, characterized in that: The photovoltaic module comprises a first area and a second area located inside the first area, and the width of the waterproof part located in the first area is greater than the width of the waterproof part in the second area; And / or, the battery body includes a main body and an edge portion located outside the main body, and a cross-sectional area of ​​the waterproof portion located at the edge portion is larger than a cross-sectional area of ​​the waterproof portion of the main body.

12. The photovoltaic module according to any one of claims 1 to 4, characterized in that: Along the second direction, the length of a portion of the collecting electrode that is not covered by the waterproof portion and the electrical connection wire accounts for less than 18% of the length of the collecting electrode.

13. The photovoltaic module according to any one of claims 1 to 4, characterized in that: Along the second direction, the collector electrodes are distributed continuously; The material of the collector electrode includes copper; The waterproof part adopts UV curing glue or thermosetting glue.

14. The photovoltaic module according to claim 5, characterized in that: Along the second direction, the distance between the electrical connection line and the adjacent waterproof portion is greater than or equal to the length of the disconnection portion.

15. The photovoltaic module according to any one of claims 5, characterized in that: A first battery cell and a second battery cell connected by an electrical connection line, a distance between a disconnection portion on the first battery cell and a center line of a corresponding disconnection portion on the second battery cell along a second direction, and the distance is less than 1.8 mm.

16. The photovoltaic module according to claim 5, characterized in that: The waterproof part is arranged on the front and back of the battery body, and the patterns of the waterproof parts on the front and back are the same; Or, the waterproof part is arranged on the front and back of the battery body, and is offset from the disconnecting parts located on the front and back; Alternatively, the pattern of the waterproof portion of each cell included in the photovoltaic module is the same.

17. A photovoltaic system, characterized in that: A photovoltaic module comprising any one of claims 1 to 16.

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