Photovoltaic cell, module and system

Abstract

The present disclosure is applicable to the technical field of solar cells. Provided are a photovoltaic cell, module and system. The photovoltaic cell comprises: a first region provided with a first busbar, the first region being provided in a first direction; a second region provided with a first finger; and a third region provided with a second finger. By means of the interdigitated back contact solar cell of the present disclosure, the operational reliability of cells can be improved.

Description

Photovoltaic cells, modules and systems

[0001] This disclosure claims priority to Chinese Patent Application No. 2024232916152, filed with the Chinese Patent Office on December 30, 2024, entitled “A Back Contact Solar Cell, Battery Module and Photovoltaic System”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure relates to the field of solar cell technology, specifically to a back-contact solar cell, a cell module, and a photovoltaic system. Background Technology

[0003] Interdigitated back contact (IBC) solar cells, also known as interdigitated back contact cells, have both positive and negative electrode grids located on the back of the cell. This completely eliminates the shading of the metal grids on the front surface, preventing optical losses caused by grid obstruction. Furthermore, the electrode grids can be designed to be wider than existing types, reducing series resistance losses and significantly improving cell conversion efficiency. Additionally, the absence of electrode grids on the front results in a more aesthetically pleasing product, making it suitable for various applications.

[0004] In related technologies, the back side of a back-contact solar cell typically includes a first region arranged along a first direction, and a second region and a third region arranged alternately along a second direction, with the second direction perpendicular to the first direction. The first region has a first main grid, the second region has a first fine grid, and the third region has a second fine grid. The polarity of the first fine grid is the same as that of the first main grid, while the polarity of the second fine grid is opposite to that of the first main grid. To prevent leakage between the second fine grid and the first main grid, and between the second fine grid and the first fine grid, isolation regions are provided for physical isolation. However, the widths of these isolation regions are typically equal, leading to a high risk of leakage between the fine grid and the non-standard main grid, making leakage a common occurrence.

[0005] Utility Model Content

[0006] This disclosure provides a back-contact solar cell, which aims to solve the problem that back-contact solar cells in the related art known to the inventors have a high risk of leakage between the fine grid and the irregular main grid, and are prone to leakage problems.

[0007] This disclosure provides a back-contact solar cell, comprising:

[0008] A first region having a first main gate, the first region extending along a first direction;

[0009] A second region is provided with a first fine gate, the second region extends along a second direction and is connected to the first region, and the polarity of the first fine gate is the same as the polarity of the first main gate;

[0010] A third region is provided with a second fine grid, the third region extends along the second direction and is spaced apart from the first region, the third region and the second region are alternately spaced along the first direction, and the second direction intersects the first direction;

[0011] The second region includes a main body region and a connection region connecting the main body region and the first region. A first isolation region is provided between the third region and the main body region of the adjacent second region. A second isolation region is provided between the third region and the first region. The width of the second isolation region along the second direction is greater than the width of the first isolation region along the first direction.

[0012] In some embodiments, a third isolation zone is provided between the third region and the connecting area of ​​the adjacent second region, and the width of the third isolation zone along the first direction is greater than the width of the first isolation zone along the first direction.

[0013] In some embodiments, the ratio of the width of the second isolation zone along the second direction to the width of the first isolation zone along the first direction is 1.1 to 2.

[0014] In some embodiments, the ratio of the width of the second isolation zone along the second direction to the width of the first isolation zone along the first direction is 1.1 to 1.5.

[0015] In some embodiments, the width of the second isolation zone along the second direction is equal to the width of the third isolation zone along the first direction.

[0016] In some embodiments, the width of the second isolation region along the second direction is 60 to 200 micrometers; the width of the first isolation region along the first direction is 66 to 300 micrometers.

[0017] In some embodiments, the width of the connection region along the first direction is greater than 100 micrometers.

[0018] In some embodiments, the width of the second isolation zone along the second direction is greater than the width of the third isolation zone along the first direction.

[0019] This disclosure provides a battery assembly including the aforementioned back-contact solar cell.

[0020] This disclosure provides a photovoltaic system including the aforementioned battery module.

[0021] This disclosure provides a back-contact solar cell comprising a first region having a first main grid, a second region having a first fine grid, and a third region having a second fine grid. The second region is disposed along a second direction and connected to the first region, and the polarity of the first fine grid is the same as that of the first main grid. The second region is disposed along the second direction and spaced apart from the first region, and the third region is disposed alternately with the second region along a first direction, the second direction being perpendicular to the first direction. A first isolation region is disposed between the third region and the main body region of the adjacent second region, and a second isolation region is disposed between the third region and the first region. The width of the second isolation region along the second direction is greater than the width of the first isolation region along the first direction, making the distance between the third region and the first region greater than the distance between the third region and the main body region of the adjacent second region, thereby improving the isolation effect between the second fine grid and the first main grid, reducing the leakage risk between the fine grid and the non-standard main grid, and improving the reliability of the cell operation. Attached Figure Description

[0022] Figure 1 is a partial structural diagram of the back side of a back-contact solar cell provided in an embodiment of this disclosure;

[0023] Figure 2 is an enlarged schematic diagram of part A in Figure 1. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this disclosure clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this disclosure.

[0025] The back-contact solar cell provided in this embodiment provides a first isolation region between a third region and the main body region of an adjacent second region, and a second isolation region between the third region and the first region. The width of the second isolation region along the second direction is greater than the width of the first isolation region along the first direction, so that the distance between the third region and the first region is greater than the distance between the third region and the main body region of the adjacent second region. This improves the isolation effect between the second fine grid and the first main grid 11, thereby reducing the leakage risk between the fine grid and the non-standard main grid and improving the reliability of the cell.

[0026] Please refer to Figures 1-2. This disclosure provides a back-contact solar cell, including:

[0027] A first region 1 is provided with a first main gate 11, and the first region 1 extends along a first direction Y;

[0028] A second region 2 is provided with a first fine gate 21. The second region 2 extends along the second direction X and is connected to the first region 1. The polarity of the first fine gate 21 is the same as the polarity of the first main gate 11.

[0029] A third region 3 is provided with a second fine grid 31. The third region 3 extends along the second direction X and is spaced apart from the first region 1. The third region 3 and the second region 2 are alternately spaced along the first direction Y. The second direction X intersects the first direction Y.

[0030] The second region 2 includes a main region 22 and a connecting region 23 connecting the main region 22 and the first region 1. A first isolation region 51 is provided between the third region 3 and the adjacent main region 22 of the second region 2. A second isolation region 52 is provided between the third region 3 and the first region 1. The width L1 of the second isolation region 52 along the second direction X is greater than the width L2 of the first isolation region 51 along the first direction Y.

[0031] Wherein, the width L1 of the second isolation zone 52 along the second direction X is the distance between the third region 3 and the first region 1, and the width L2 of the first isolation zone 51 along the first direction Y is the distance between the third region 3 and the main body area 22 of the adjacent second region 2. It can be understood that the distance between the third region 3 and the first region 1 is greater than the distance between the third region 3 and the main body area 22 of the adjacent second region 2.

[0032] In this embodiment, the first region 1, the second region 2, and the third region 3 are all disposed on the back side of the back-contact solar cell. The first region 1 and the second region 2 have the same polarity, and the third region 3 has the opposite polarity to the first region 1 and the second region 2. For example, the first region 1 and the second region 2 can be P-type regions, the first main grid 11 and the first fine grid 21 can be P-type grid lines, and the third region 3 can be an N-type region, with the second fine grid 31 being an N-type grid line; alternatively, the first region 1 and the second region 2 can be N-type regions, the first main grid 11 and the first fine grid 21 can be N-type grid lines, and the third region 3 can be a P-type region, with the second fine grid 31 being a P-type grid line.

[0033] In this embodiment, the first direction Y intersects with the second direction X. In some embodiments, the first direction Y is perpendicular to the second direction X. The first direction Y is the same as the width direction of the first region 1, and the second direction X is the same as the width direction of the first region 1. The specific number of second regions 2 and third regions 3 is not limited, nor is the specific number of first regions 1. In some embodiments, there are multiple second regions 2 and multiple third regions 3, each second region 2 and each third region 3 is disposed along the second direction X, and the multiple second regions 2 and multiple third regions 3 are alternately disposed along the first direction Y.

[0034] In this embodiment, each second region 2 includes a main region 22 and a connection region 23 connecting the main region 22 and the first region 1. Each third region 3 is provided with a first isolation region 51 between itself and the main region 22 of the adjacent second region 2, and a second isolation region 52 is provided between itself and the first region 1. The width L1 of the second isolation region 52 along the second direction X is greater than the width L2 of the first isolation region 51 along the first direction Y, so that the distance between the third region 3 and the first region 1 is greater than the distance between the third region 3 and the main region 22 of the adjacent second region 2. This improves the isolation effect between the second fine grid 31 and the first main grid 11, thereby improving the isolation effect between the fine grid and the non-standard main grid, reducing the leakage risk between the fine grid and the non-standard main grid, improving the leakage protection reliability between the fine grid and the non-standard main grid, and improving the battery working reliability.

[0035] As an embodiment of this disclosure, a third isolation zone 53 is provided between the third region 3 and the connection zone 23 of the adjacent second region 2. The width L3 of the third isolation zone 53 along the first direction Y is greater than the width L2 of the first isolation zone 51 along the first direction Y.

[0036] In this embodiment, the third region 3 and the connection area 23 of the adjacent second region 2 are physically isolated by the third isolation area 53. Since the connection area 23 is located close to the first region 1, the width of the third isolation area 53 along the first direction Y is set to be greater than the width L2 of the first isolation area 51 along the first direction Y. This makes the distance between the connection area 23 of the third region 3 and the adjacent second region 2 greater than the distance between the main body area 22 of the third region 3 and the adjacent second region 2. This can improve the isolation effect between the connection area 23 of the third region 3 and the adjacent second region 2, thereby improving the isolation effect between the first fine grid 21 and the second fine grid 31. At the same time, it can also further improve the isolation effect between the connection area 23 of the third region 3 and the adjacent second region 2, thereby further reducing the leakage risk between the second fine grid 31 and the first main grid 11.

[0037] The first isolation zone 51, the second isolation zone 52, and the third isolation zone 53 are all isolation troughs, such as laser troughs. The first isolation zone 51, the second isolation zone 52, and the third isolation zone 53 are interconnected to form an integrated isolation trough. This disclosure divides the isolation trough into the first isolation zone 51, the second isolation zone 52, and the third isolation zone 53 to distinguish the different areas of the isolation trough.

[0038] As an embodiment of this disclosure, the first isolation region 51, the second isolation region 52, and the third isolation region 53 are all isolation grooves. The first isolation region 51, the second isolation region 52, and the third isolation region 53 can be square isolation grooves, or of other shapes. If the first isolation region 51, the second isolation region 52, and the third isolation region 53 are of other shapes or irregular shapes, then the width L1 of the second isolation region 52 along the second direction X can be understood as the minimum width of the second isolation region 52 along the second direction X, the width L2 of the first isolation region 51 along the first direction Y is the minimum width of the first isolation region 51 along the first direction Y, and the width of the third isolation region 53 along the first direction Y is the minimum width of the third isolation region 53 along the first direction Y.

[0039] As one embodiment of this disclosure, the ratio of the width L1 of the second isolation region 52 along the second direction X to the width L2 of the first isolation region 51 along the first direction Y is 1.1 to 2.

[0040] In this embodiment, the ratio of the width L1 of the second isolation region 52 along the second direction X to the width L2 of the first isolation region 51 along the first direction Y is 1.1 to 2. This keeps the ratio of the width L1 of the second isolation region 52 along the second direction X to the width L2 of the first isolation region 51 along the first direction Y within a suitable range. This can improve the isolation effect between the second fine gate 31 and the first main gate 11, and also avoid excessively widening the second isolation region 52, which would shorten the width of the second fine gate 31 and affect current collection. This achieves a balance between leakage prevention performance and current collection performance.

[0041] For example, the ratio of the width L1 of the second isolation zone 52 along the second direction X to the width L2 of the first isolation zone 51 along the first direction Y can be any value among 1.1, 1.12, 1.2, 1.25, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, and 2.0.

[0042] As one embodiment of this disclosure, the ratio of the width L1 of the second isolation region 52 along the second direction X to the width L2 of the first isolation region 51 along the first direction Y is 1.1 to 1.5.

[0043] In this embodiment, the ratio of the width L1 of the second isolation region 52 along the second direction X to the width L2 of the first isolation region 51 along the first direction Y is further set to 1.1 to 1.5, so that the ratio of the width L1 of the second isolation region 52 along the second direction X to the width L2 of the first isolation region 51 along the first direction Y is kept in a more suitable range. This can improve the isolation effect between the second fine gate 31 and the first main gate 11, and also ensure that the second fine gate 31 has a suitable width, maintain a good current collection effect, and achieve a better balance between leakage prevention and current collection effect.

[0044] As one embodiment of this disclosure, the width L1 of the second isolation zone 52 along the second direction X is equal to the width L3 of the third isolation zone 53 along the first direction Y.

[0045] In this embodiment, the width L1 of the second isolation region 52 along the second direction X is equal to the width L3 of the third isolation region 53 along the first direction Y, which facilitates the processing of the second isolation region 52 and the third isolation region 53, and also facilitates the battery printing process.

[0046] As an embodiment of this disclosure, the width L2 of the first isolation region 51 along the first direction Y is 60 to 200 micrometers, and the width L1 of the second isolation region 52 along the second direction X is 66 to 300 micrometers.

[0047] In this embodiment, the width L2 of the first isolation region 51 along the first direction Y is 60-200 micrometers, and the width L1 of the second isolation region 52 along the second direction X is 66-300 micrometers. It is only necessary to satisfy that the width L1 of the second isolation region 52 along the second direction X is greater than the width L2 of the first isolation region 51 along the first direction Y. This can achieve a good isolation effect between the first isolation region 51 and the second isolation region 52, and can avoid reducing the area of ​​the first region 1, the second region 2 and the third region 3 as much as possible, thus affecting the current collection effect.

[0048] For example, the width L2 of the first isolation region 51 along the first direction Y can be any value among 60 micrometers, 62 micrometers, 65 micrometers, 70 micrometers, 72 micrometers, 80 micrometers, 83 micrometers, 90 micrometers, 98 micrometers, 100 micrometers, 110 micrometers, 120 micrometers, 130 micrometers, 140 micrometers, 150 micrometers, 160 micrometers, 170 micrometers, 180 micrometers, 190 micrometers, and 200 micrometers; the width of the second isolation region 52 along the first direction Y... The micrometer can be any value among 66 micrometers, 68 micrometers, 70 micrometers, 73 micrometers, 80 micrometers, 85 micrometers, 90 micrometers, 99 micrometers, 100 micrometers, 115 micrometers, 126 micrometers, 135 micrometers, 142 micrometers, 158 micrometers, 166 micrometers, 172 micrometers, 180 micrometers, 190 micrometers, 200 micrometers, 210 micrometers, 230 micrometers, 240 micrometers, 260 micrometers, 280 micrometers, 290 micrometers, and 300 micrometers.

[0049] As one embodiment of this disclosure, the width of the connection region 23 along the first direction Y is greater than 100 micrometers.

[0050] In this embodiment, the width direction of the connection region 23 between the third region 3 and the adjacent second region 2 is along the first direction Y. The width of the connection region 23 between the third region 3 and the adjacent second region 2 is greater than 100 micrometers, ensuring sufficient width of the connection region 23 between the second region 2 and ensuring good current collection effect of the first fine gate 21.

[0051] In another embodiment of this disclosure, the width L1 of the second isolation region 52 along the second direction X is greater than the width L3 of the third isolation region 53 along the first direction Y.

[0052] In this embodiment, the width L1 of the second isolation region 52 along the second direction X is set to be greater than the width L3 of the third isolation region 53 along the first direction Y, so that the isolation effect between the third region 3 and the first region 1 is better than the isolation effect between the third region 3 and the connection area 23 of the adjacent second region 2. This can further improve the isolation effect between the third region 3 and the first region 1 and further reduce the leakage risk between the second fine grid 31 and the first main grid 11.

[0053] This disclosure also provides a battery assembly including the back-contact solar cell described above. It should be noted that this battery assembly has the same or similar beneficial effects as the back-contact solar cell described above, and the related aspects between the two can be referred to each other; to avoid repetition, they will not be repeated here.

[0054] In this embodiment, multiple back-contact solar cells in the battery module can be connected in series to form a battery string, thereby achieving series current output. For example, the battery cells can be connected in series by setting solder strips (busbars, interconnecting strips), conductive backplates, etc.

[0055] It is understood that in such embodiments, the battery assembly may also include a metal frame, a backsheet, photovoltaic glass, and an encapsulating film. The encapsulating film may be filled between the front and back of the back-contact solar cell, the photovoltaic glass, adjacent cells, etc. As a filler, it may be a transparent colloid with good light transmittance and aging resistance. For example, the encapsulating film may be an EVA film or a POE film, and the specific choice can be made according to the actual situation, without limitation.

[0056] Photovoltaic glass can be applied to the encapsulating film on the front side of the back-contact solar cell. This photovoltaic glass can be ultra-clear glass, possessing high light transmittance, high transparency, and superior physical, mechanical, and optical properties. For example, ultra-clear glass can achieve a light transmittance of over 92%. It can protect the back-contact solar cell while minimizing impact on its efficiency. Simultaneously, the encapsulating film bonds the photovoltaic glass and the back-contact solar cell together, providing sealing, insulation, and waterproofing / moisture protection for the back-contact solar cell.

[0057] The backsheet can be attached to the adhesive film on the back of the back-contact solar cell. The backsheet protects and supports the solar cell, providing reliable insulation, water resistance, and aging resistance. Multiple backsheet options are available, typically including tempered glass, acrylic glass, and aluminum alloy TPT composite adhesive film, etc. The specific choice depends on the specific circumstances and is not limited here. The backsheet, back-contact solar cell, adhesive film, and photovoltaic glass can be mounted on a metal frame. The metal frame serves as the main external support structure for the entire back-contact solar cell module, providing stable support and installation. For example, the back-contact solar cell module can be installed at the desired location using the metal frame.

[0058] This disclosure also provides a photovoltaic system including the battery module described above. It should be noted that this photovoltaic system has the same or similar beneficial effects as the back-contact solar cell described above, and the related aspects between the two can be referred to each other; to avoid repetition, they will not be repeated here.

[0059] In this embodiment, the photovoltaic system can be applied in photovoltaic power plants, such as ground-mounted power plants, rooftop power plants, and floating power plants. It can also be applied to equipment or devices that utilize solar energy to generate electricity, such as user solar power supplies, solar streetlights, solar cars, and solar buildings. Of course, it is understood that the application scenarios of the photovoltaic system are not limited to these; that is, the photovoltaic system can be applied in all fields that require solar energy to generate electricity. Taking a photovoltaic power generation system grid as an example, the photovoltaic system may include a photovoltaic array, a combiner box, and an inverter. The photovoltaic array may be an array combination of multiple back-contact solar cell modules. For example, multiple back-contact solar cell modules can form multiple photovoltaic arrays. The photovoltaic array is connected to the combiner box, which can collect the current generated by the photovoltaic array. The collected current flows through the inverter and is converted into AC power required by the mains power grid before being connected to the mains power grid to achieve solar power supply.

[0060] The above are merely preferred embodiments of this disclosure and are not intended to limit this disclosure. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

Claims

1. A back-contact solar cell, wherein, include: A first region having a first main gate, the first region extending along a first direction; A second region is provided with a first fine gate, the second region extends along a second direction and is connected to the first region, and the polarity of the first fine gate is the same as the polarity of the first main gate; A third region is provided with a second fine grid, the third region extends along the second direction and is spaced apart from the first region, the third region and the second region are alternately spaced along the first direction, and the second direction intersects the first direction; The second region includes a main body region and a connection region connecting the main body region and the first region. A first isolation region is provided between the third region and the main body region of the adjacent second region. A second isolation region is provided between the third region and the first region. The width of the second isolation region along the second direction is greater than the width of the first isolation region along the first direction.

2. The back-contact solar cell according to claim 1, wherein, A third isolation zone is provided between the third region and the connecting area of ​​the adjacent second region, and the width of the third isolation zone along the first direction is greater than the width of the first isolation zone along the first direction.

3. The back-contact solar cell according to claim 1, wherein, The ratio of the width of the second isolation zone along the second direction to the width of the first isolation zone along the first direction is 1.1 to 2.

4. The back-contact solar cell according to claim 3, wherein, The ratio of the width of the second isolation zone along the second direction to the width of the first isolation zone along the first direction is 1.1 to 1.

5.

5. The back-contact solar cell according to claim 2, wherein, The width of the second isolation zone along the second direction is equal to the width of the third isolation zone along the first direction.

6. The back-contact solar cell according to claim 1, wherein, The width of the second isolation region along the second direction is 60 to 200 micrometers; the width of the first isolation region along the first direction is 66 to 300 micrometers.

7. The back-contact solar cell according to claim 1, wherein, The width of the connection area along the first direction is greater than 100 micrometers.

8. The back-contact solar cell according to claim 2, wherein, The width of the second isolation zone along the second direction is greater than the width of the third isolation zone along the first direction.

9. A battery assembly, wherein, Including the back-contact solar cell as described in any one of claims 1 to 8.

10. A photovoltaic system, wherein, Includes the battery assembly as described in claim 9.

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