Solar battery pack and photovoltaic system

Abstract

The utility model is applicable to the field of photovoltaic technology, and provides a solar battery pack and a photovoltaic system, the solar battery pack comprises at least two groups of solar batteries arranged along the vertical direction, at least one surface of each solar battery comprises a plurality of repetitive areas, each repetitive area comprises at least two minimum battery units, and the minimum battery units are arranged in the vertical direction. The minimum battery unit comprises an N region and a P region; metal grid lines are arranged in a P area and an N area in each minimum battery unit, the extension direction of the metal grid lines is consistent with the length extension direction of the P area and the N area, bus bars are arranged between every two adjacent sets of solar batteries, and the bus bars are arranged along the arrangement direction of the solar batteries. The metal grid line on the P area of the previous solar cell and the metal grid line on the N area of the next solar cell are respectively connected with the bus bar, or the N line of the previous solar cell and the P line of the next solar cell are respectively connected with the bus bar. The efficiency change proportion from the battery to the assembly and the yield of the battery piece and the assembly are improved, and the mechanical performance and the reliability are improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of photovoltaics, and in particular relates to a solar cell group and a photovoltaic system. Background Art

[0002] The back junction cell uses photolithography technology to diffuse phosphorus and boron locally on the back of the cell, forming a P region and N region with finger-like cross arrangement, as well as a P+ region and n+ region located above them. The P+ and N+ regions formed by heavy expansion can effectively eliminate the voltage saturation effect under high concentration conditions. In addition, the coverage area of ​​the P+ and N+ region contact electrodes almost reaches 1 / 2 of the back surface, greatly reducing the series resistance.

[0003] At present, the fine grid area of ​​the back junction battery usually uses a single step structure, and different areas of the battery cell (such as the edge, etc.) have different carrier collection capabilities. Therefore, the existing battery cell structure cannot maximize the carrier collection and has low collection efficiency. In addition, the current path from the battery cell to the bus bar is long and uneven, which easily leads to increased resistance loss and affects the overall efficiency of the battery. Utility Model Content

[0004] The utility model provides a solar cell group and a photovoltaic system, aiming to solve the problems of low collection efficiency and resistance loss of existing solar cells, which substantially reduce the overall efficiency of the cells.

[0005] The utility model is implemented as follows: a solar cell group includes at least two groups of solar cells arranged in a vertical direction, at least one side of the solar cell includes a plurality of repeated regions, the repeated region includes at least two minimum battery cells, the minimum battery cells include an N region and a P region: any two minimum battery cells are respectively a first unit and a second unit, the first unit and the second unit have different P region widths, and / or different N region widths;

[0006] In each of the minimum battery cells, metal gate lines are respectively arranged in the P region and the N region, and the extension direction of the metal gate lines is consistent with the length extension direction of the P region and the N region;

[0007] A bus bar is arranged between two adjacent groups of solar cells. Along the arrangement direction of the solar cells, the metal grid lines on the P region of the solar cell of the previous level and the metal grid lines on the N region of the solar cell of the next level are respectively connected to the bus bar, or the N lines of the solar cell of the previous level and the P lines of the solar cell of the next level are respectively connected to the bus bar.

[0008] Optionally, each of the repeating regions includes one first unit and at least three second units.

[0009] Optionally, the total width of the first unit is 1 to 3 times the total width of the second unit.

[0010] Optionally, the width of the P region in the first unit is 0.3 to 3 times the width of the P region in the second unit; the width of the N region in the first unit is 0.3 to 3 times the width of the N region in the second unit.

[0011] Optionally, a width ratio of the N region to the P region in each of the minimum battery cells is 2:8 to 8:2.

[0012] Optionally, the repeated region further includes at least two PNG units, the PNG units include an N region, a P region, and a G region, any two of the PNG units are respectively a third unit and a fourth unit, and the third unit and the fourth unit satisfy at least one of the following:

[0013] The width of the P region is different;

[0014] The width of the N region is different;

[0015] The width of the G area is different.

[0016] Optionally, the P region widths of the third unit and the fourth unit are different and / or the N region widths are different, and the G region widths of the third unit and the fourth unit are the same.

[0017] Optionally, the total width of the third unit is 1 to 3 times the total width of the fourth unit.

[0018] Optionally, the width of the P region in the third unit is 0.3 to 3 times the width of the P region in the fourth unit; the width of the N region in the third unit is 0.3 to 3 times the width of the N region in the fourth unit.

[0019] Optionally, a width ratio of the N region to the P region in each of the PNG units is 2:8 to 8:2.

[0020] Optionally, the width of the metal gate line in the P region in the first unit and the width of the metal gate line in the P region in the second unit are in a ratio of 0.05:20; the width of the metal gate line in the N region in the first unit and the width of the metal gate line in the N region in the second unit are in a ratio of 0.05:20.

[0021] Optionally, a distance between the metal gate line and the adjacent N region or P region is greater than or equal to 10 μm.

[0022] Optionally, the second unit also includes a G zone.

[0023] The utility model also provides a photovoltaic system, comprising the above-mentioned solar cell group.

[0024] The beneficial effects achieved by the utility model are that the utility model improves the light absorption range of the solar cell, increases the probability of collecting photocurrent, and improves the efficiency change ratio from the cell to the module and the yield of the cell and the module by adjusting the width difference between the N region and the P region. In addition, since the design of the metal grid line is consistent with the extension direction of the electrode, the sufficiency of current collection and the effectiveness of conduction are ensured, the resistance loss is reduced, and a fine metal bearing film layer is provided for the back of the cell, which enhances the load performance of the cell and the module, and improves the overall mechanical performance and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of the structure of the first solar cell group provided by the present invention;

[0026] Figure 2 It is a structural schematic diagram of the second solar cell group provided by the present invention;

[0027] Figure 3 This is a schematic diagram of the structure of the first solar cell provided by the present invention;

[0028] Figure 4 It is a structural schematic diagram of the second solar cell provided by the present invention;

[0029] Figure 5 This is a schematic diagram of the structure of the third solar cell provided by the present invention;

[0030] Figure 6 It is a schematic diagram of the structure of the fourth solar cell provided by the present invention;

[0031] Figure 7 It is a structural schematic diagram of the fifth solar cell provided by the present invention;

[0032] Figure 8 It is a structural schematic diagram of the sixth solar cell provided by the present invention;

[0033] Fig. 9 It is a structural schematic diagram of the seventh solar cell provided by the present invention;

[0034] Fig.10 It is a structural schematic diagram of the eighth solar cell provided by the present invention;

[0035] Fig.11 It is a schematic diagram of the structure of the ninth solar cell provided by the present invention;

[0036] Fig.12 It is a schematic diagram of the structure of the tenth solar cell provided by the present invention;

[0037] Fig.13 It is a schematic structural diagram of the eleventh solar cell provided by the present invention.

[0038] Description of reference numerals:

[0039] 100, solar cell group; 110, solar cell; 111, first unit; 112, second unit; 113, third unit; 114, fourth unit; 115, metal grid line; 116, bus bar. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. Examples of embodiments are shown in the accompanying drawings, in which the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the utility model, and cannot be understood as limiting the utility model. In addition, it should be understood that the specific embodiments described herein are only used to explain the utility model and are not used to limit the utility model.

[0041] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "left", "right", "horizontal", "top", "bottom", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention.

[0042] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0043] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "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 a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0044] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0045] The disclosure below provides many different embodiments or examples for realizing different structures of the utility model. In order to simplify the disclosure of the utility model, the components and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the utility model. In addition, the utility model can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, and does not indicate the relationship between the various embodiments and / or settings discussed in itself. In addition, the utility model provides various specific examples of processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use of other materials.

[0046] The utility model improves the light absorption range of solar cells, increases the probability of collecting photocurrent, and improves the efficiency change ratio from cell to module and the yield rate of cells and modules by adjusting the width difference between N and P regions. The design of the metal grid line is consistent with the extension direction of the electrode, which ensures the adequacy of current collection and the effectiveness of conduction, reduces resistance loss, and provides a fine metal bearing film layer on the back of the cell, which enhances the load performance of the cell and module and improves the overall mechanical performance and reliability.

[0047] Embodiment 1

[0048] like Figure 1 and Figure 2 As shown, this embodiment provides a solar cell group 100, including at least two groups of solar cells 110 arranged in a vertical direction, at least one side of the solar cell 110 includes a plurality of repeated regions, the repeated region includes at least two minimum battery units, the minimum battery unit includes an N region and a P region: any two minimum battery units are respectively a first unit 111 and a second unit 112, the first unit 111 and the second unit 112 have different P region widths, and / or different N region widths;

[0049] In each minimum battery cell, metal gate lines 115 are respectively arranged in the P region and the N region, and the extension direction of the metal gate lines 115 is consistent with the length extension direction of the P region and the N region;

[0050] A bus bar 116 is arranged between two adjacent groups of solar cells 110. Along the arrangement direction of the solar cells 110, the metal grid lines 115 on the P region of the upper-level solar cell 110 and the metal grid lines 115 on the N region of the lower-level solar cell 110 are respectively connected to the bus bar 116, or the N lines of the upper-level solar cell 110 and the P lines of the lower-level solar cell 110 are respectively connected to the bus bar 116.

[0051] A plurality of repeating regions are arranged on one or both sides of the solar cell 110, each repeating region includes two or more minimum battery cells, the minimum battery cells included in each repeating region are the same as the minimum battery cells included in other repeating regions, and a plurality of identical repeating regions are arranged repeatedly. It is understandable that the repeating region does not have to cover the entire cell sheet, and a portion of the cell sheet may not be composed of the repeating region.

[0052] Each minimum battery unit includes an N region and a P region. The full name of the N region is N-type semiconductor region, which can be an N-type doped region formed by phosphorus diffusion doping, an N-type silicon substrate, or an N+ region formed by ion implantation or other methods; the full name of the P region is P-type semiconductor, which can be a P-type doped region formed by boron diffusion doping, a P-type silicon substrate, a P+ aluminum back field formed by aluminum paste sintering, or a P+ region formed by ion implantation or other methods. A minimum battery unit can be a PN unit, where the N region and the P region are adjacently arranged, or a PNG unit, where a GAP region is also arranged between the N region and the P region. The GAP region is also called a photogenerated charge separation layer, which can be an undoped silicon-based region, a shallowly doped region, or other electrically poor conductor structures. It is located between the P region and the N region to achieve spatial separation of the PN junction and effectively solve the problem of leakage in the P and N contact regions.

[0053] For example, two minimum battery cells are set in a single repeating area. Figure 3 As shown, there can be two PN units in one repeating region, such as Figure 4 As shown, it can also be a PN unit and a PNG unit.

[0054] Any two minimum battery cells are the first cell 111 and the second cell 112, and the first cell 111 and the second cell 112 are arranged adjacent to each other. Specifically, the widths of the P regions of the first cell 111 and the second cell 112 are different but the widths of the N regions are the same, such as Figure 5As shown; it is also possible that the widths of the N regions of the first unit 111 and the second unit 112 are different but the widths of the P regions are the same, such as Figure 6 As shown; it is also possible that the width of the P region and the width of the N region of the first unit 111 and the second unit 112 are different, but the width of the P region and the N region in the first unit 111 are the same, and the width of the P region and the N region in the second unit 112 are different, such as Figure 7 As shown; it is also possible that the width of the P region and the width of the N region of the first unit 111 and the second unit 112 are different, but the width of the P region and the N region in the second unit 112 are the same, and the width of the P region and the N region in the first unit 111 are different, such as Figure 8 As shown; it is also possible that the width of the P region and the width of the N region of the first unit 111 and the second unit 112 are different, and the width of the P region and the N region in the first unit 111 are the same, and the width of the P region and the N region in the second unit 112 are the same, as shown Figure 3 The above examples do not exhaustively list all possibilities, and do not exclude other possibilities that the widths of the P regions of the first unit 111 and the second unit 112 are different, and / or the widths of the N regions are different. Specifically, the N region and the P region in the smallest battery cell can be laid on the same plane, or the N region and the P region can be partially overlapped.

[0055] This solar cell 110 can be realized by using different materials and processes. By precisely controlling the width of the N region and the P region, the charge separation efficiency and power output performance of the solar cell 110 under different lighting conditions can be adjusted. For example, the charge transfer and power collection effect can be optimized by controlling the width of the P region to improve the photoelectric conversion efficiency of the battery. In addition, by adjusting the width difference between the N region and the P region, the light absorption range and photoelectric conversion efficiency of the solar cell 110 can be improved, and the light energy resources can be utilized to the greatest extent. The probability of collecting photocurrent is greatly increased without affecting the production capacity, and the efficiency change ratio from battery to module and the yield of battery cells and modules are improved.

[0056] During the manufacturing process, advanced process technologies such as photolithography and chemical deposition can be used to accurately define and control the structural dimensions of the N and P regions. At the same time, material selection is also crucial, and high-efficiency photovoltaic materials such as silicon, cadmium selenide or gallium arsenide can be used to achieve higher photoelectric conversion efficiency.

[0057] It should be understood that this design can optimize the performance of the solar cell 110 and improve its stability and flexibility when the lighting conditions change. By adjusting the widths of the N region and the P region, the cell characteristics can be fine-tuned to meet the requirements of different application scenarios. In the photovoltaic field, this design can provide new ideas and possibilities for the research and development of solar cells 110, and help promote the advancement and application of solar photovoltaic technology.

[0058] At least two groups of solar cells 110 are arranged in a vertical direction. Specifically, two adjacent groups of solar cells may be placed side by side, or two adjacent groups of solar cells may be arranged side by side with a difference of 180°, which is not limited here.

[0059] In each minimum battery cell, metal grid lines 115 are set in the P region and the N region respectively, and the extension direction of the metal grid lines 115 is consistent with the length direction of the P region and the N region. The metal grid lines 115 completely overlap with the electrode structure to complete electrical conduction, change the flow path of the current from the battery cell to the bus bar, and collect current more fully. At the same time, the metal grid lines 115 can cover the length of the battery cell to the maximum extent and optimize current collection. The number of metal grid lines 115 is consistent with the number of electrode structures on the solar cell 110, which is equivalent to setting a fine metal bearing film layer on the back of the battery cell, improving the load performance of the battery cell and the component, and more current extraction possibilities.

[0060] The metal grid line 115 is set between the P region and the N region and keeps a certain distance, which is not only to maintain the independence of electrical performance, but also to prevent the occurrence of electrical faults such as short circuits. It should be understood that this layout design can be achieved through precise lithography and deposition technology to ensure that the position and distance of each metal grid line 115 meet the design requirements. These processes can be achieved through high-precision PLC control devices to ensure the manufacturing accuracy of each minimum battery unit.

[0061] In addition, in practical applications, the metal grid lines 115 corresponding to the P region and the N region respectively should not only have good conductivity, but also have certain mechanical strength and flexibility to adapt to various operations during the production and installation of the solar cell 110. It is understandable that the selection of appropriate metal materials and structural design is particularly critical, which is also a necessary condition for improving the overall performance and reliability of the battery.

[0062] In actual operation, the distance between the metal gate line 115 in the P region and the adjacent N region, as well as the distance between the metal gate line 115 in the N region and the adjacent P region are kept greater than 0. This can not only effectively avoid the recombination loss of photogenerated carriers in the battery structure and increase the current collection efficiency, but also reduce internal stress concentration, thereby improving the mechanical stability of the battery.

[0063] A bus bar 116 is provided between two adjacent groups of solar cells 110, and the metal grid lines 115 on the P region of the upper solar cell and the metal grid lines 115 on the N region of the lower solar cell are respectively connected to the bus bar 116, or the metal grid lines 115 on the N region of the upper solar cell and the metal grid lines 115 on the P region of the lower solar cell are respectively connected to the bus bar 116. This ensures smooth conduction of current between different levels, reduces resistance loss, and improves current conduction efficiency.

[0064] Specifically, the metal gate line 115 on the P region and the metal gate line 115 on the N region extend in two opposite directions, such as Figure 2 As shown, the metal gate line 115 in the P region extends downward, and the metal gate line 115 in the N region extends upward, or as shown in FIG. Figure 1 As shown, the metal grid line 115 in the P region extends upward, while the metal grid line 115 in the N region extends downward, so that the metal grid line 115 on the P region (N region) of the upper-level solar cell and the metal grid line 115 on the N region (P region) of the lower-level solar cell are connected to the bus bar 116 respectively.

[0065] In this embodiment, by adjusting the width difference between the N region and the P region, the light absorption range of the solar cell 110 is improved, the probability of collecting photocurrent is increased, and the efficiency change ratio from the cell to the module and the yield of the cell and the module are improved. The design of the metal grid line 115 is consistent with the extension direction of the electrode, which ensures the sufficiency of current collection and the effectiveness of conduction, reduces resistance loss, and provides a fine metal bearing film layer on the back of the cell, which enhances the load performance of the cell and the module and improves the overall mechanical performance and reliability.

[0066] In one embodiment, when the smallest battery cell is a PN cell, the P region and the N region are adjacently arranged, and the distance between the metal gate line 115 and the adjacent N region or P region is greater than or equal to 10 μm. 10 μm is a safe distance to prevent the metal gate line 115 from being accidentally touched.

[0067] In another embodiment, when the minimum battery cell is a PNG cell, a G region is provided between the P region and the N region, and the adjacent P region and the N region are all G regions. The distance between the metal gate line 115 and the adjacent G region is greater than 0. Preferably, the distance between the metal gate line 115 and the adjacent G region is greater than or equal to 25 μm. 25 μm is a safe distance to avoid the metal line being set in the G region and being unable to conduct current. At the same time, the distance between the metal gate line 115 and the adjacent N region or P region is greater than 0, which can effectively reduce the interference between the gate lines and ensure the independent conduction of the current.

[0068] Embodiment 2

[0069] Based on the first embodiment, each repeating region includes one first unit 111 and at least three second units 112 .

[0070] In the simulation experiment of photovoltaic cells, it was found that the theoretical efficiency of the smallest battery cell with a width of 1.2mm was 26.914%, and the theoretical efficiency of the smallest battery cell with a width of 0.8mm was 27.132%. By combining three 0.8mm and one 1.2mm, the efficiency was 27.088%, and the efficiency reduction was <0.05%. The efficiency loss was small, but it could greatly improve the electrical yield of the smallest battery cell.

[0071] The actual efficiency of the smallest battery cell can be estimated by the following formula:

[0072] Assuming that the two smallest battery cells are pitch1 and pitch2, the theoretical photoelectric conversion efficiency of the smallest battery cell with pitch1 width w1 is: Eta1;

[0073] The theoretical photoelectric conversion efficiency of the minimum battery unit with a pitch2 width of w2 is: Eta2;

[0074] If there are n1 Pitch1s and n2 Pitch2s in the repeating area, its efficiency can be estimated as the arithmetic mean Eta = (n1×w1×Eta1+n2×w2×Eta1) / (n1×w1+n2×w2). The process suitable for production can be inferred based on the calculated efficiency and yield values. If the expected efficiency value is Eta1, a structure with (Eta-Eta1) < 0.05% is selected for design.

[0075] According to experimental data, when the ratio of the number of the first unit 111 to the second unit 112 in the repeating area is greater than 1:3, the impact on efficiency is small, and the improvement effect on the electrical yield of the battery cell is obvious. The specific ratio can be calculated according to actual needs using the above calculation formula.

[0076] Embodiment 3

[0077] Based on the first embodiment, the total width of the first unit 111 is 1 to 3 times the total width of the second unit 112 .

[0078] In the simulation experiment of photovoltaic cells, it was found that the theoretical efficiency of the smallest battery cell with a width of 0.4mm is 27.23%. If a combination of a smallest battery cell with a width of 0.4mm and a smallest battery cell with a width of 1.3mm is used, the efficiency is 27.01%, and the efficiency reduction value is 0.22%. The efficiency loss is too large to meet the needs of improving battery design efficiency.

[0079] Specifically, the total width of the first unit 111 may be greater than the total width of the second unit 112 . Laboratory verification shows that when the total width of the first unit 111 is not greater than three times the total width of the second unit 112 , the impact on the cell efficiency is small.

[0080] The total width of the first unit 111 may be the same as the total width of the second unit 112. Specifically, the width of the N region of the first unit 111 is consistent with the width of the P region of the second unit 112, and the width of the N region of the second unit 112 is consistent with the width of the P region of the first unit 111. The actual width can be set according to specific usage requirements.

[0081] Embodiment 4

[0082] Based on the third embodiment, the width of the P region in the first unit 111 is 0.3 to 3 times the width of the P region in the second unit 112 ; the width of the N region in the first unit 111 is 0.3 to 3 times the width of the N region in the second unit 112 .

[0083] The width of the P region in the first cell 111 may be smaller than the width of the P region in the second cell 112, for example, the width of the P region in the first cell 111 is 0.3 times the width of the P region in the second cell 112; the width of the P region in the first cell 111 may be larger than the width of the P region in the second cell 112, for example, the width of the P region in the first cell 111 is 3 times the width of the P region in the second cell 112. According to laboratory data, when the width of the P region in the first cell 111 is 0.3 to 3 times the width of the P region in the second cell 112, the impact on battery efficiency is small and the battery appearance is more beautiful.

[0084] The width of the N region in the first cell 111 may be smaller than the width of the N region in the second cell 112, for example, the width of the N region in the first cell 111 is 0.3 times the width of the N region in the second cell 112; the width of the N region in the first cell 111 may be larger than the width of the N region in the second cell 112, for example, the width of the N region in the first cell 111 is 3 times the width of the N region in the second cell 112. According to laboratory data, when the width of the N region in the first cell 111 is 0.3 to 3 times the width of the N region in the second cell 112, the impact on battery efficiency is small and the battery appearance is more beautiful.

[0085] The ratio of the width of the P region in the first unit 111 to the width of the P region in the second unit 112 , and the ratio of the width of the N region in the first unit 111 to the width of the N region in the second unit 112 , can be set according to actual usage requirements.

[0086] Embodiment 5

[0087] Based on the first embodiment, the width ratio of the N region to the P region in each minimum battery unit is 2:8 to 8:2.

[0088] In the simulation experiment of photovoltaic cells, it was found that for the smallest battery unit with a width of 1.2mm, when the width ratio of the P region and the N region is 1:1, its efficiency is 26.95%; when the width ratio of the P region and the N region is 1:5, its efficiency is 26.63%, and the efficiency reduction value is 0.32%. The efficiency loss is too large to meet the needs of battery design efficiency improvement; when the width ratio of the P region and the N region is 5:1, its efficiency is 26.71%, and the efficiency reduction value is 0.24%. The efficiency loss is too large to meet the needs of battery design efficiency improvement.

[0089] According to laboratory data, when the width ratio of the N region and the P region in each minimum battery cell is 2:8 to 8:2, the impact on battery efficiency is small and the battery appearance is more beautiful.

[0090] Specifically, in a minimum battery cell, the width of the N region may be greater than the width of the P region, for example, the ratio of the width of the N region to the width of the P region may be 6:4; the width of the N region may also be equal to the width of the P region, for example, the ratio of the width of the N region to the width of the P region may be 1:1; the width of the N region may also be smaller than the width of the P region, for example, the ratio of the width of the N region to the width of the P region may be 4:6.

[0091] Embodiment 6

[0092] On the basis of the first embodiment, the repeated area further includes at least two PNG units, the PNG unit includes an N region, a P region, and a G region, any two of which are a third unit 113 and a fourth unit 114, respectively, and the third unit 113 and the fourth unit 114 satisfy at least one of the following:

[0093] The width of the P region is different;

[0094] The width of the N region is different;

[0095] The width of the G area is different.

[0096] The repeated area includes at least two minimum battery cells and at least one PNG unit. The PNG unit includes an N region, a P region and a G region. The G region, namely the GAP region, is located between the P region and the N region in order to achieve spatial separation of the PN junction and effectively solve the leakage problem of the P and N contact regions.

[0097] Any two PNG units are the third unit 113 and the fourth unit 114, and the third unit 113 and the fourth unit 114 are arranged adjacent to each other. Specifically, the widths of the P regions of the third unit 113 and the fourth unit 114 are different, but the widths of the N regions are the same, such as Fig. 9 As shown; it is also possible that the widths of the N regions of the third unit 113 and the fourth unit 114 are different but the widths of the P regions are the same, such as Fig.10 As shown; it is also possible that the width of the P region and the width of the N region of the third unit 113 and the fourth unit 114 are different, but the width of the P region and the N region in the third unit 113 are the same, and the width of the P region and the N region in the fourth unit 114 are different, such as Fig.11 As shown; it is also possible that the width of the P region and the width of the N region of the third unit 113 and the fourth unit 114 are different, but the width of the P region and the N region in the fourth unit 114 are the same, and the width of the P region and the N region in the third unit 113 are different, such as Fig.12As shown; it is also possible that the width of the P region and the width of the N region of the third unit 113 and the fourth unit 114 are different, and the width of the P region and the N region in the third unit 113 are the same, and the width of the P region and the N region in the fourth unit 114 are the same, as Fig.13 The above examples also include two cases where the widths of the P regions of the third unit 113 and the fourth unit 114 are the same or different.

[0098] Embodiment 7

[0099] like Figures 9 to 13 As shown, based on the sixth embodiment, the third unit 113 and the fourth unit 114 have different P region widths and / or different N region widths, and the third unit 113 and the fourth unit 114 have the same G region widths.

[0100] The width of the G region is an important parameter in the solar cell 110. A narrower G region can promote the rapid separation of photogenerated charges and prevent charge recombination. Therefore, a smaller G region width helps to improve the photoelectric conversion efficiency of the battery. However, it will increase resistance and affect the current collection effect.

[0101] The width of the G region of the third unit 113 is the same as that of the fourth unit 114. Keeping the width of each G region equal can ensure the uniformity and consistency of the battery structure, help control and optimize the performance of the battery during the production process, and reduce the uneven effect in different regions. Having the same width of the G region can simplify the manufacturing process, does not require additional process steps to adjust the size of different regions, and is more convenient for arranging and setting the battery cells, which is conducive to improving production efficiency and reducing production costs.

[0102] In one embodiment, the total width of the third unit 113 is 1 to 3 times the total width of the fourth unit 114. Through laboratory verification, when the total width of the third unit 113 is not greater than three times the total width of the fourth unit 114, the impact on the efficiency of the battery cell is small. The specific width can be set according to actual usage requirements.

[0103] In one embodiment, the width of the P region in the third cell 113 is 0.3 to 3 times the width of the P region in the fourth cell 114; the width of the N region in the third cell 113 is 0.3 to 3 times the width of the N region in the fourth cell 114. According to laboratory data, when the third cell 113 and the fourth cell 114 meet the above conditions, the impact on battery efficiency is small and the battery appearance is more beautiful. The ratio of the width of the P region in the third cell 113 to the width of the P region in the fourth cell 114, and the ratio of the width of the N region in the third cell 113 to the width of the N region in the fourth cell 114, can be set according to actual usage requirements.

[0104] In one embodiment, the width ratio of the N region to the P region in each PNG unit is 2:8 to 8:2. Specifically, in a PNG unit, the width of the N region can be greater than the width of the P region, the width of the N region can be equal to the width of the P region, and the width of the N region can be less than the width of the P region. According to laboratory data, when the width ratio of the N region to the P region in each PNG unit is 2:8 to 8:2, the impact on battery efficiency is small and the battery appearance is more beautiful.

[0105] Embodiment 8

[0106] Based on the first embodiment, the width of the metal gate line 115 in the P region of the first unit 111 and the width of the metal gate line 115 in the P region of the second unit 112 are in a ratio of 0.05:20; the width of the metal gate line 115 in the N region of the first unit 111 and the width of the metal gate line 115 in the N region of the second unit 112 are in a ratio of 0.05:20.

[0107] In this embodiment, the proportional relationship between the widths of the metal grid lines 115 in different units of the solar cell 110 is further described. Specifically, the ratio of the width of the P-region metal grid line 115 in the first unit 111 to the width of the P-region metal grid line 115 in the second unit 112 is 0.05:20; similarly, the ratio of the width of the N-region metal grid line 115 in the first unit 111 to the width of the N-region metal grid line 115 in the second unit 112 is also 0.05:20. This design detail can be understood as optimizing the overall performance of the solar cell 110 by changing the widths of the metal grid lines 115 in different units.

[0108] The advantage is that by designing metal gate lines 115 of different widths between the first unit 111 and the second unit 112 , the current collection path can be optimized and the charge carrier collection efficiency can be improved.

[0109] The metal gate lines 115 with narrower widths have a higher density in a specific area, thereby improving the current collection capability in a small area.

[0110] The arrangement of metal grid lines 115 of different widths may help reduce the overall circuit resistance, thereby reducing power loss and increasing output power. Metal grid lines 115 of different widths can help disperse the heat generated in the battery and avoid the occurrence of overheating areas, thereby improving stability and service life. High-precision photolithography technology and metal deposition technology are used to accurately control and manufacture metal grid lines 115 of different widths to meet specific ratio requirements. Metal materials (such as silver, aluminum or copper) with high conductivity, corrosion resistance and suitable mechanical properties are selected to make metal grid lines 115.

[0111] Specifically, the width of the P-region and N-region metal gate lines 115 in the first unit 111: For example, the metal gate lines 115 in the P-region and N-region of the first unit 111 may be set to a minimum width, such as 10 μm. Compared with the first unit 111, the width of the P-region and N-region metal gate lines 115 in the second unit 112 is 20 times that of the first unit 111, that is, 200 μm.

[0112] Through the above design, the overall performance of the solar cell 110 can be more balanced, efficient and stable. This design helps to adapt to the electrical performance requirements under different light intensities and different installation conditions. This will form a significant width difference between different units, thereby affecting the current collection efficiency and resistance characteristics.

[0113] In summary, the solar cell 110 designed by controlling the width ratio of the metal grid lines 115 in the first and second units 112 can significantly improve the overall photoelectric conversion efficiency and optimize thermal management and current collection routes, providing strong technical advantages for commercial applications.

[0114] Embodiment 9

[0115] This embodiment provides a photovoltaic system, including the solar cell group 100 of the above embodiment.

[0116] The beneficial effects of the photovoltaic system of this embodiment are equivalent to the beneficial effects of the above-mentioned solar cell group 100, and will not be described in detail here.

[0117] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A solar cell group, characterized in that: The invention comprises at least two groups of solar cells arranged in a vertical direction, wherein at least one side of the solar cell comprises a plurality of overlapping regions, wherein the overlapping regions comprise at least two minimum battery units, and wherein the minimum battery units comprise an N region and a P region. Any two minimum battery units are respectively a first unit and a second unit, wherein the P region widths of the first unit and the second unit are different, and / or the N region widths are different; In each of the minimum battery cells, metal gate lines are respectively arranged in the P region and the N region, and the extension direction of the metal gate lines is consistent with the length extension direction of the P region and the N region; A bus bar is arranged between two adjacent groups of solar cells. Along the arrangement direction of the solar cells, the metal grid lines on the P region of the solar cell of the previous level and the metal grid lines on the N region of the solar cell of the next level are respectively connected to the bus bar, or the N lines of the solar cell of the previous level and the P lines of the solar cell of the next level are respectively connected to the bus bar.

2. The solar cell group according to claim 1, characterized in that: Each of the repeating regions includes one first unit and at least three second units.

3. The solar cell group according to claim 1, characterized in that: The total width of the first unit is 1 to 3 times the total width of the second unit.

4. The solar cell group according to claim 3, characterized in that: The width of the P region in the first unit is 0.3 to 3 times the width of the P region in the second unit; the width of the N region in the first unit is 0.3 to 3 times the width of the N region in the second unit.

5. The solar cell group according to claim 1, characterized in that: The width ratio of the N region to the P region in each of the minimum battery cells is 2:8 to 8:

2.

6. The solar cell array according to claim 1, characterized in that: The repeating region further includes at least two PNG units, the PNG units include an N region, a P region, and a G region, any two of the PNG units are respectively a third unit and a fourth unit, and the third unit and the fourth unit satisfy at least one of the following: The width of the P region is different; The width of the N region is different; The width of the G area is different.

7. The solar cell group according to claim 6, characterized in that: The P region widths of the third unit and the fourth unit are different and / or the N region widths are different, and the G region widths of the third unit and the fourth unit are the same.

8. The solar cell group according to claim 6, characterized in that: The total width of the third unit is 1 to 3 times the total width of the fourth unit.

9. The solar cell group according to claim 8, characterized in that: The width of the P region in the third unit is 0.3 to 3 times the width of the P region in the fourth unit; the width of the N region in the third unit is 0.3 to 3 times the width of the N region in the fourth unit.

10. The solar cell group according to claim 6, characterized in that: The width ratio of the N region to the P region in each of the PNG units is 2:8 to 8:

2.

11. The solar cell array according to claim 1, characterized in that: The width of the metal gate line in the P region in the first unit and the width of the metal gate line in the P region in the second unit are in a ratio of 0.05:20; the width of the metal gate line in the N region in the first unit and the width of the metal gate line in the N region in the second unit are in a ratio of 0.05:

20.

12. The solar cell array according to claim 1, characterized in that: The distance between the metal gate line and the adjacent N region or P region is greater than or equal to 10 μm.

13. The solar cell array according to claim 1, characterized in that: The second unit also includes a G zone.

14. A photovoltaic system, characterized in that: Comprising a solar cell group as claimed in any one of claims 1 to 13.

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