Rectangular photovoltaic cell and photovoltaic module

Abstract

The invention discloses a rectangular photovoltaic cell and a photovoltaic module, and relates to the technical field of solar cells, a plurality of main grid lines are arranged on a cell substrate of the rectangular photovoltaic cell, and the direction of the main grid lines of the cell substrate is the length direction; the length Lc of the battery base body is 180 mm + X mm, and the value of X is 0 mm to 6.477 mm; the width Wc of the battery base body is 210mm + Ymm, and the value of Y is 0 mm to 2.367 mm; the cell substrate is provided with a bisection parting line, and the bisection parting line is arranged in the middle of the cell substrate and is perpendicular to the main grid line direction of the cell substrate. The photovoltaic module comprises a plurality of battery strings, and battery pieces in the battery strings are half-piece batteries obtained by cutting rectangular photovoltaic batteries along bisecting cutting lines of the rectangular photovoltaic batteries. By adopting the design parameters of the rectangular photovoltaic cell and the photovoltaic module designed by the invention, under the condition of the photovoltaic cell with the same size, the length and the width of a single module can reach the industrial acceptable size maximum value, and the number of the main grids can be increased to 18-32, so that the collection and the transmission of photo-induced electrons of the cell are facilitated, and the photoelectric conversion efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of solar cells, and in particular to a rectangular photovoltaic cell and a photovoltaic module. Background Art

[0002] The photovoltaic market currently mainly uses photovoltaic modules with half-cell technology, and its size is closely related to the number of photovoltaic cell strings used and the number of cells connected in series in each string of cells. The width of the module is related to the width of the cell and the number of cell strings. Usually, in order to maintain industry versatility, the number of cell strings is designed to be an even number. Currently, the industry mostly uses a 6-string design. The length of the module is related to the number of cells connected in series in each cell string. Usually, the number of cells connected in series in each cell string is 8 to 13 (take an integer).

[0003] If you want to increase the width of a module using half-cell technology, you usually need to increase the width of the cell by an even multiple, at least twice the width of the cell. For example, the mainstream cell widths in the industry are 210mm and 182mm, of which the 210mm wide cell corresponds to a module width of 1303mm, which is the maximum module width currently accepted by the industry; and the 182mm wide cell corresponds to a module width of 1134mm. If you want to increase the width, you need to increase it by at least twice 182mm, that is, 364mm, so the width of the module will reach 1498mm, which exceeds the maximum width currently accepted by the industry.

[0004] To increase the length of a module, it is usually necessary to increase the length by an even multiple of half the length of the battery cell, that is, to increase the length of at least one battery cell (or twice the length of half a battery cell). Taking the current mainstream battery cell lengths of 182mm and 210mm in the industry as an example, the maximum length of the module corresponding to the 182mm-long battery is 2465mm, which is the maximum length of the module currently accepted by the industry; and the maximum length of the module corresponding to the 210mm-long battery is 2384mm. If the length is to be increased, it is necessary to increase by at least 210mm, so that the length of the module will reach 2594mm, which is also beyond the maximum length currently accepted by the industry.

[0005] In summary, under the market mainstream design parameters of the existing technology of 182mm×182mm square sheet, 210mm×210mm square sheet and rectangular size (the current maximum size in the industry is 182mm×210mm), the corresponding maximum length of the photovoltaic module can reach 2465mm, and the maximum width can reach 1303mm; however, the length and width cannot simultaneously reach the maximum acceptable size of the market. Summary of the invention

[0006] The purpose of the present invention is to design a rectangular photovoltaic cell wire mesh and photovoltaic cell whose interconnection direction (or main grid direction) is parallel to the shorter side, and to electrically interconnect the designed rectangular photovoltaic cells in series or parallel to form a photovoltaic module. This design can maximize the number of cells that can be packaged in a single photovoltaic module within the acceptable silicon wafer size, photovoltaic cell size and module size range in the industry, and at the same time, it can also combine optical and electrical optimization to further improve the power generation efficiency of the designed photovoltaic module.

[0007] To achieve the above object, in one aspect, the present invention provides a rectangular photovoltaic cell, comprising a rectangular cell substrate, wherein a plurality of main grid lines are arranged on the cell substrate, and the direction of the main grid lines of the cell substrate is the length direction;

[0008] The length Lc of the battery matrix is ​​180mm+Xmm, where the value of X is 0mm-6.477mm;

[0009] The width Wc of the battery matrix is ​​210mm+Ymm, and the value of Y is 0mm-2.367mm;

[0010] The battery substrate is provided with a bisecting dividing line, which is arranged in the middle of the battery substrate and is perpendicular to the main grid line direction of the battery substrate.

[0011] Preferably, the number of busbars on the front or back side of the battery substrate is 18-32, and the extending direction of the busbars is the same as the interconnection direction of the rectangular photovoltaic cells and is parallel to the short sides of the battery substrate.

[0012] Preferably, the battery matrix adopts one of P-type passivated emitter technology, N-type passivated emitter back full diffusion technology, tunneling oxide layer passivation contact technology, heterojunction technology or cross back contact technology.

[0013] On the other hand, the present invention provides a photovoltaic module, including a plurality of battery strings, wherein the battery strings are formed by connecting a plurality of battery cells in series, and the battery cells are half-cells obtained by cutting the rectangular photovoltaic cell described in any one of the above items along its bisecting dividing line.

[0014] Preferably, the battery string includes 13 battery cells, and the cell spacing Dc between two adjacent battery cells ranges from -0.5 mm to 3.01 mm.

[0015] Preferably, the front or back sides of the first and last battery cells of the battery string lead out conductive materials with lengths of Lr1 and Lr2 respectively, wherein Lr1+Lr2=15 mm, and the difference between Lr1 and Lr2 is ≤1 mm.

[0016] Preferably, the component length Lm=2*(13*Lc / 2+12*Dc)+2Crs+2Lr2+Wh+6mm, wherein Lc is the length of the battery matrix, Dc is the distance between two adjacent battery cells, Crs is the short side creepage distance, Lr2 is the lead-out length of the conductive material, and Wh is the blank width in the middle; the value range of Crs is 10.4mm-39.5mm, the value range of Lr2 is 7mm-8mm, and the value range of Wh is 10mm-13mm.

[0017] Preferably, the component width Wm=6*Wc+Crl1+Crl2+Ds1+Ds2+Ds3+Ds4+Ds5+6mm, wherein Crl1 and Crl2 are the long side creepage distances, Ds1-Ds5 are the string spacing of the battery strings; 0.4mm≤Crl1≤18.5mm or 0.4mm≤Crl2≤18.5mm, and the difference between Crl1 and Crl2≤2mm; the value ranges of Ds1, Ds2, Ds3, Ds4 and Ds5 are all 0.2mm-2.44mm.

[0018] Preferably, the difference between every two parameters of the string spacing Ds1, Ds2, Ds3, Ds4, Ds5 of the battery string is ≤0.5, and Ds1 or Ds5≥Ds2 or Ds3 or Ds4, and Ds2 or Ds4≥Ds3.

[0019] The present invention discloses the following technical effects:

[0020] Compared with the mainstream design in the industry, the rectangular photovoltaic cell and photovoltaic module design parameters designed by the present invention can achieve the maximum acceptable size of the industry in terms of length and width of a single module under the condition of the same size of 182.2mm*210mm photovoltaic cell; the number of cells that can be packaged in a single module can also be increased from 66 full cells (132 half cells) to 78 full cells (156 half cells). At the same time, under the same 182.2mm*210mm size photovoltaic cell condition, the number of main grids can be increased from the traditional 16 to 18-32, which is more conducive to the collection and transmission of photogenerated electrons in the cell and increases the photoelectric conversion efficiency of the photovoltaic cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 This is a schematic structural diagram of a rectangular photovoltaic cell according to Embodiment 1 of the present invention;

[0023] Figure 2 is a design parameter diagram of a battery string in a photovoltaic module according to Embodiment 2 of the present invention;

[0024] Figure 3 A diagram showing the design parameters for the laying process of photovoltaic modules according to Embodiment 2 of the present invention;

[0025] Figure 4 for Figure 3 A partial enlarged view of the middle A;

[0026] In the figure: 1. Main grid line; 2. Secondary grid line; 3. Bisection dividing line; 4. Conductive material; 5. Busbar. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In traditional photovoltaic modules, the size of photovoltaic cells is mainly square, that is, the length and width of photovoltaic cells are the same. As the difficulty of increasing the power of photovoltaic cells increases, the adjustment of the size of photovoltaic cells has become a fast and effective technical means to increase the power of photovoltaic cells and photovoltaic modules. The size of corresponding silicon wafers and photovoltaic cells has gradually transitioned from 125mm*125mm and 166mm*166mm to two mainstream sizes of 182mm*182mm and 210mm*210mm; although the size of photovoltaic cells is getting bigger and bigger, the shape has always been square. From 2022 to 2023, rectangular silicon wafers and photovoltaic cells began to appear in the photovoltaic industry; among them, one side of the rectangular size is mainly based on the 182mm size, and the length of the other side is greater than 182mm and does not exceed 210mm. Compared with square silicon wafers, rectangular photovoltaic cells can increase the power and efficiency of the module on the one hand, and make more full use of silicon materials on the other hand, reducing the production and application costs of silicon wafers and corresponding silicon wafers, photovoltaic cells and photovoltaic modules.

[0029] With the emergence of rectangular wafer sizes for photovoltaic cells, in order to avoid the waste of resources caused by the disorderly development of the corresponding photovoltaic module sizes in the market, the industry has also gradually standardized the sizes of photovoltaic modules corresponding to rectangular photovoltaic cells. According to the statistical data of the "China Photovoltaic Industry Development Roadmap" newly released by the China Photovoltaic Industry Association in February 2024, combined with the development trend of upstream silicon wafer sizes, excluding sizes of 166mm*166mm and below, 182mm*182mm square wafers, 210mm*210mm square wafers and rectangular sizes (the current maximum size in the industry is 182mm*210mm) have become the mainstream sizes in the market, accounting for 47.7%, 20.7%, and 10% of the market respectively; at the same time, half-cell technology has become the mainstream technology in the industry with a share of 97.1%. Combining half-cell technology and rectangular-sized photovoltaic cells, the maximum sizes of photovoltaic modules currently acceptable to the market are as follows:

[0030] 1. Based on 182mm*182mm square photovoltaic cells, the maximum size of the photovoltaic module is 2465mm*1134mm, and the number of packaged cells is 78 full cells, that is, 156 half cells;

[0031] 2. Based on 210mm*210mm square photovoltaic cells, the maximum size of the photovoltaic module is 2384mm*1303mm, and the number of packaged cells is 66 whole cells, that is, 132 half cells;

[0032] 3. Based on 182mm*210mm rectangular photovoltaic cells, the maximum size of the photovoltaic module is 2382mm*1134mm, and the number of packaged cells is 66 whole cells, or 132 half cells.

[0033] Based on the above dimensions, the current maximum length of photovoltaic modules in the industry is 2465mm (the corresponding maximum width of the module is 1134mm), and the maximum width is 1303mm (the corresponding maximum length of the module is 2384mm).

[0034] The present technical invention proposes a rectangular photovoltaic cell and photovoltaic module. By matching the rectangular cell size and laying parameters, the maximum width of the photovoltaic module can be further optimized; typically, matching the industry's more common 182.2*210mm size photovoltaic cells, the corresponding photovoltaic module can reach the maximum width of 1.303 meters currently acceptable to the industry.

[0035] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] Embodiment 1:

[0037] Reference Figure 1As shown, Embodiment 1 of the present invention provides a rectangular photovoltaic cell, including a rectangular cell substrate, a plurality of main grid lines 1 are arranged on the cell substrate, and the direction of the main grid lines 1 of the cell substrate is the length direction; the length Lc of the cell substrate is 180mm+Xmm, X is 0mm-6.477mm, the width Wc is 210mm+Ymm, Y is 0mm-2.367mm; the length Lc of the cell substrate is less than the width Wc of the cell substrate, as shown in FIG. Figure 1 As shown. The values ​​of the length Lc and width Wc of the cell matrix fully consider the current mainstream size of 182.2mm*210mm in the industry, and based on the length and width of the photovoltaic module to be designed by the present invention, 2465mm*1303mm, the size of the silicon wafer and the photovoltaic cell can be optimized within a certain range, thereby further increasing the effective power generation area of ​​the photovoltaic cell to be packaged within the size range of the designed photovoltaic module.

[0038] The rectangular photovoltaic cell of this embodiment is provided with a bisecting dividing line 3 on the cell substrate. The bisecting dividing line 3 is provided in the middle of the cell substrate and is perpendicular to the main grid line 1 of the rectangular photovoltaic cell.

[0039] In a specific embodiment, the technology type of the rectangular photovoltaic cell can be P-type passivated emitter technology (P-PERC) in crystalline silicon, N-type passivated emitter back fully diffused technology (N-PERT), tunneling oxide passivation contact technology (TOPCon), heterojunction technology (HJT) or cross back contact technology (IBC), etc.

[0040] In some optional embodiments, in addition to the cross back contact technology (IBC), a rectangular photovoltaic cell using other technical routes is provided with a certain number of main grid lines 1 and auxiliary grid lines 2 on the front and back sides, wherein the number of main grid lines 1 is 18-32, and their extension direction is the same as the interconnection direction of the rectangular photovoltaic cell, and is parallel to the relatively short side of the rectangular photovoltaic cell, and the position of the main grid line 1 on the front side of the photovoltaic cell corresponds to the position of the main grid line 1 on the back side of the photovoltaic cell; and for the rectangular photovoltaic cell using the cross back contact technology, the main grid line 1 and the auxiliary grid line 2 are both located on the back side of the cell.

[0041] Taking the 182.2mm*210mm rectangular photovoltaic cell, which is the mainstream in the industry, as an example, the length of the existing photovoltaic cell is 180mm+Xmm, X is 2.2mm, the width is 210mm+Ymm, and Y is 0mm. Compared with the prior art, the rectangular photovoltaic cell of the embodiment of the present invention has a length Lc that is smaller than the width Wc; the length is 180+Xmm (X is 0mm-6.477mm) and the width is (210+Y)mm (Y is 0mm-2.367mm). The number of main grids on the front or back is 18-32; and the interconnection direction is parallel to the length direction of the rectangular photovoltaic cell, that is, parallel to the smaller side of the rectangular photovoltaic cell. The main grid or auxiliary grid is not printed in the bisecting dividing line 3 area, and is located at the half of the rectangular photovoltaic cell and perpendicular to the shorter side of the rectangular photovoltaic cell.

[0042] Embodiment 2:

[0043] Reference Figures 2 to 4 As shown, Example 1 of the present invention provides a photovoltaic module, which includes a plurality of battery strings, wherein the battery strings are formed by connecting a plurality of battery cells in series, and the battery cells are half-cells obtained by cutting the rectangular photovoltaic cells described in Example 1 along the dividing line 3 that divides them into two equal parts.

[0044] The photovoltaic module of this embodiment combines the design standards of the photovoltaic module related industry and the operability of the manufacturing production line to design parameters for the laying process of the designed rectangular photovoltaic cell. The main factors to be considered in the parameter design include the pollution level of the packaging material used in the photovoltaic module, the electrical clearance between the conductive parts inside the photovoltaic module, the creepage distance between the conductive parts inside the photovoltaic module and the outside of the module, and other electrical safety, combined with the matching of the length and width dimensions of the photovoltaic cell and photovoltaic module to be designed.

[0045] Specifically, Figure 2As shown, the battery string contains 13 battery cells, which are half-cells obtained by cutting a rectangular photovoltaic cell along its bisecting dividing line 3, and the interval Dc between two adjacent battery cells ranges from -0.5mm to 3.01mm; the length of the battery string is set to Ls, then Ls = 13*Lc / 2+12*Dc. The length of the photovoltaic module Lm = 2*(13*Lc / 2+12*Dc)+2Crs+2Lr2+Wh+6; the unit is mm; among which, the range of Dc is -0.5mm-3.01mm; the range of Crs is 10.4mm-39.5mm; the range of Lr2 is 7mm-8mm; the range of Wh is 10mm-13mm. The width of the photovoltaic module Wm=6*Wc+Crl1+Crl2+Ds1+Ds2+Ds3+Ds4+Ds5+6; the unit is mm; wherein, Crl1≥10.4mm or Crl2≤18.5mm, and the difference between Crl1 and Crl2≤2mm; the value ranges of Ds1, Ds2, Ds3, Ds4 and Ds5 are all 0.2mm-2.44mm, and the difference between each two parameters of Ds1, Ds2, Ds3, Ds4 and Ds5 is ≤0.5, and (Ds1 or Ds5)≥(Ds2 or Ds3 or Ds4), and (Ds2 or Ds4)≥Ds3.

[0046] In this embodiment, the length Lc of the battery cell is 180mm+Xmm, where X ranges from 0mm to 6.477mm, and the width Wc of the battery cell is 210mm+Ymm, where Y ranges from 0mm to 2.367mm. Compared with the prior art,

[0047] In this embodiment, the photovoltaic module encapsulates a total of 78 whole rectangular photovoltaic cells of the above size, that is, 156 half cells.

[0048] In a specific embodiment, in order to make electrical connections such as series and parallel connection of the battery string, the front or back side of the first and last battery cells of the battery string are led out to a certain length using a conductive material 4, and the lengths are Lr1 and Lr2 respectively, wherein Lr1+Lr2=15mm, and the difference between Lr1 and Lr2 is ≤1mm, that is, the value range of Lr1 or Lr2 is 7mm-8mm.

[0049] In some optional embodiments, the conductive material 4 used to electrically connect two adjacent solar cells may be a conductive tape, a photovoltaic welding tape, a metal wire or other conductive material 4.

[0050] In a specific embodiment, the photovoltaic module includes two symmetrical left and right parts, namely Figure 3The two parts H1 and H2 shown in the figure are composed of 6 battery strings connected in series, and H1 and H2 are connected in parallel to form the core power generation component of the photovoltaic module. The photovoltaic module contains a total of 78 whole rectangular photovoltaic cells of the designed size of 180mm+Xmm*210mm+Ymm, that is, 156 half cells.

[0051] like Figure 3 As shown, the main design parameters and value ranges in the photovoltaic module laying process designed by the present invention are as follows:

[0052] Based on the electrical safety of photovoltaic modules and the dimensions of the designed photovoltaic cells and photovoltaic modules, the creepage distance of the long side of the designed photovoltaic module is 10.4mm≤Crl1 or Crl2≤18.5mm, and the difference between Crl1 and Crl2 is ≤2mm;

[0053] The string spacings of the battery strings inside the photovoltaic module are Ds1, Ds2, Ds3, Ds4, and Ds5 respectively. Considering the fluidity of the internal packaging film during the lamination process during the production of photovoltaic modules, and based on the electrical safety of photovoltaic modules and the size of the designed photovoltaic cells, the value ranges of Ds1, Ds2, Ds3, Ds4 and Ds5 are all 0.2mm-2.44mm; wherein, the difference between each two parameters in Ds1, Ds2, Ds3, Ds4 and Ds5 is ≤0.5; and (Ds1 or Ds5) ≥ (Ds2 or Ds3 or Ds4); and (Ds2 or Ds4) ≥ Ds3; wherein, the lower limit of the value range of Ds1-Ds5 fully considers the electrical clearance and safety of the conductive parts inside the photovoltaic module, and the upper limit of the value range of Ds1-Ds5 combines the width size of the photovoltaic cell designed by the present invention, the width size of the photovoltaic module, and the creepage distance and safety of the conductive parts inside the photovoltaic module to the edge of the photovoltaic module;

[0054] Based on the electrical safety of photovoltaic modules and the size of the designed photovoltaic cells and photovoltaic modules, the creepage distance Crs of the short side of the designed photovoltaic module is 10.4mm-39.5mm; the width of the blank space in the middle Wh is 11mm-12mm;

[0055] like Figure 4 As shown, the lead-out length Lr1+Lr2 of the conductive material 4 on the front or back side of the first and last cells in the cell string of the photovoltaic module is 15 mm, and the difference between Lr1 and Lr2 is ≤1 mm; and in the middle area of ​​the module, the lead-out length of the conductive material 4 and the overlap length Lw of the busbar 5 are ≥70% of the width Wb of the busbar 5.

[0056] The semi-finished products output from the laying process are assembled with junction boxes and frames to form the photovoltaic module designed in this embodiment; wherein the length and width of the frame are the length Lm and width Wm of the photovoltaic module; and the length Lm and width Wm are 6 mm larger than the length and width of the corresponding laminate, respectively.

[0057] In a specific embodiment, the value of the inter-chip spacing Dc is 1.6mm; the value of the short side creepage distance Crs is 12.5mm; the value of the lead-out length Lr2 of the conductive material 4 is 7.5mm; the value of the width Wh of the blank space in the middle is 12mm; then the length of the designed photovoltaic module Lm = 2*(13*Lc / 2+12*Dc)+2Crs+2Lr2+Wh+6=2465mm; the length of the designed photovoltaic module can be maximized in the industry; at the same time, the values ​​of the inter-chip spacing Dc, the short side creepage distance Crs and the width Wh of the blank space in the middle are also friendly to the current process.

[0058] In a specific embodiment, the value of the long side creepage distance Crl1 is 12.5mm; the value of the long side creepage distance Crl2 is 13.5mm; the string spacing Ds1 and Ds5 of the battery strings inside the photovoltaic module are 2.3mm; the values ​​of Ds2 and Ds4 are 2.2mm; the value of Ds3 is 2mm; then the width of the designed photovoltaic module Wm=6*Wc+Crl1+Crl2+Ds1+Ds2+Ds3+Ds4+Ds5+6=1303mm; the width of the designed photovoltaic module can be maximized in the industry; at the same time, in the laying process, the differentiated design of the battery string spacing is also conducive to improving the yield of the finished photovoltaic module.

[0059] By applying the rectangular photovoltaic cell and photovoltaic module design parameters designed by the present invention, the number of rectangular photovoltaic cells of the same size of 182.2mm*210mm that can be packaged in a single photovoltaic module of reasonable size can be increased from the original maximum of 66 whole pieces (132 half pieces) to 78 whole pieces (156 half pieces). At the same time, the mainstream design of the industry has 16 to 18 main grids for the battery, while the number of main grids for the rectangular photovoltaic cell designed by the present invention can be increased to more than 18. The designed main grid can more effectively share the photocurrent generated by photovoltaic cells of the same size, while improving the transmission efficiency of photogenerated carriers of photovoltaic cells, it can reduce the series resistance of the corresponding photovoltaic module, and further improve the photoelectric conversion efficiency of the photovoltaic module.

[0060] At present, the mainstream photovoltaic cells in the industry adopt a size design of 182.2mm*210mm. The main grid of the photovoltaic cell is parallel to the longer side (i.e. the 210mm side), that is, the main grid is parallel to the 210mm side, and the bisecting dividing line on the photovoltaic cell is perpendicular to the longer side (i.e. the 210mm side) of the photovoltaic cell; the photovoltaic module using the above-mentioned 182.2mm*210mm photovoltaic cell has a length of 2382mm and a width of 1134mm. In a single photovoltaic module, the number of encapsulated cells is 66, i.e. 132 half cells.

[0061] Based on the above-mentioned 182.2mm*210mm photovoltaic cell photovoltaic module, if the width of the photovoltaic module is to be further increased, the module width needs to be increased by at least 182*2mm, that is, 364mm, and the corresponding module width is 1498mm, which exceeds the maximum width currently accepted by the industry; if the length of the photovoltaic module is to be further increased, the module length needs to be increased by at least 210mm, and the corresponding module length is 2594mm, which exceeds the maximum length currently accepted by the industry.

[0062] For rectangular photovoltaic cells with a size of 182.2mm*210mm, the industry has currently restricted and standardized the size of the components, that is, the length of the components is unified to 2382mm, and the width of the components is unified to 1134mm; under this size restriction, the cell spacing Dc of the components is within the range of 0.8mm-1mm, so that the requirements of the length of the components can be met by matching the short side creepage distance Crs of appropriate size and the width Wh of the blank space in the middle under the premise that the current industry production line process can be achieved. Among them, the cell spacing value of less than 1mm will further improve the industry's requirements for the processing accuracy and stability of production line equipment; at the same time, the design of small spacing will also increase the fragmentation rate of crystalline silicon photovoltaic cells in the welding process.

[0063] In addition, the industry generally designs the string spacing (Ds1-Ds5) to be equal. However, in the current production process of photovoltaic modules in the industry, due to the melting and flow of the internal packaging film of the module during the lamination process, the internal battery strings are usually offset to varying degrees, which ultimately causes the originally designed equal string spacing values ​​to change to varying degrees. In severe cases, adjacent battery strings may come into contact, which may cause short circuits and burnout of photovoltaic modules during outdoor power generation.

[0064] Compared with the existing designs, the rectangular photovoltaic cells and photovoltaic modules disclosed in Embodiments 1 and 2 of the present invention have at least the following beneficial effects:

[0065] The photovoltaic module designed in the present invention is suitable for the processing process of the half-cell of the rectangular photovoltaic cell of the present invention; at the same time, it is also suitable for a half-cell photovoltaic cell with the same size design as the half-cell of the rectangular photovoltaic cell, that is, the length of the half-cell photovoltaic cell is Lc / 2 and the width is Wc, and the main grid line 1 of the photovoltaic cell is parallel to the side with a length of Lc / 2.

[0066] The length Lm of the photovoltaic module of the present invention is 2*(13*Lc / 2+12*Dc)+2Crs+2Lr2+Wh+6; the unit is mm; wherein the value range of Dc is -0.5mm-3.01mm; the value range of Crs is 10.4mm-39.5mm; the value range of Lr2 is 7mm-8mm; the value range of Wh is 10mm-13mm;

[0067] The width of the photovoltaic module of the present invention is Wm=6*Wc+Crl1+Crl2+Ds1+Ds2+Ds3+Ds4+Ds5+6; the unit is mm; wherein, Crl1 or Crl2≥10.4mm, and the difference between Crl1 and Crl2≤2mm; the value ranges of Ds1, Ds2, Ds3, Ds4 and Ds5 are all 0.2mm-2.44mm, and the difference between each two parameters of Ds1, Ds2, Ds3, Ds4, Ds5 is ≤0.5, and (Ds1 or Ds5)≥(Ds2 or Ds3 or Ds4), and (Ds2 or Ds4)≥Ds3.

[0068] By adopting rectangular photovoltaic cells of the size designed by the present invention and matching the main design parameters of the photovoltaic module designed by the present invention, the length of the corresponding photovoltaic module is 2465mm±2mm; at the same time, the width of the designed photovoltaic module is 1303mm±2mm; at the same time, the number of rectangular photovoltaic cells of the size of (180+X)mm*(210+Y)mm encapsulated in the photovoltaic module designed by the present invention is 78 pieces.

[0069] The rectangular photovoltaic cell size and photovoltaic module design parameters designed in the present invention are suitable for photovoltaic cells of HJT, BC and "super-multi-main-grid" or "main-grid-free" technology routes, wherein the "super-multi-main-grid" technology includes a number greater than 32 conductive components arranged on the front or back of the photovoltaic cell and parallel to the shorter side of the cell, and the conductive components include conductive metal wires, conductive glue, conductive tapes, conductive pastes, etc.; the "main-grid-free" technology includes only conductive components arranged on the front or back of the photovoltaic cell and parallel to the longer side of the cell, and the conductive components include conductive metal wires, conductive glue, conductive tapes, conductive pastes, etc.

[0070] The details not described in detail in the present invention are all conventional technical means well known to those skilled in the art.

[0071] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, 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, and therefore should not be understood as a limitation on the present invention.

[0072] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A rectangular photovoltaic cell, characterized in that: A battery substrate having a rectangular shape is provided on the battery substrate, and the main grid lines of the battery substrate are located in the longitudinal direction; The length Lc of the battery matrix is ​​180mm+Xmm, where the value of X is 0mm-6.477mm; The width Wc of the battery matrix is ​​210mm+Ymm, and the value of Y is 0mm-2.367mm; The battery substrate is provided with a bisecting dividing line, which is arranged in the middle of the battery substrate and is perpendicular to the main grid line direction of the battery substrate.

2. The rectangular photovoltaic cell according to claim 1, characterized in that: The number of main grid lines on the front or back side of the battery substrate is 18-32, and the extending direction of the main grid lines is the same as the interconnection direction of the rectangular photovoltaic cells and is parallel to the short side of the battery substrate.

3. The rectangular photovoltaic cell according to claim 1, characterized in that: The battery matrix adopts one of the following technologies: P-type passivated emitter technology, N-type passivated emitter back full diffusion technology, tunneling oxide layer passivation contact technology, heterojunction technology or cross back contact technology.

4. A photovoltaic module, comprising a plurality of battery strings, wherein the battery strings are formed by connecting a plurality of battery cells in series, characterized in that: The cell sheet is a half-cell obtained by cutting the rectangular photovoltaic cell according to any one of claims 1 to 3 along its bisecting dividing line.

5. The photovoltaic module according to claim 4, characterized in that: The battery string includes 13 battery cells, and the cell spacing Dc between two adjacent battery cells ranges from -0.5 mm to 3.01 mm.

6. The photovoltaic module according to claim 5, characterized in that: The front or back side of the first and last battery cells in the battery string lead out conductive materials with lengths of Lr1 and Lr2 respectively, wherein Lr1+Lr2=15mm, and the difference between Lr1 and Lr2 is ≤1mm.

7. The photovoltaic module according to claim 6, characterized in that: The component length Lm of the photovoltaic module is Lm = 2*(13*Lc / 2+12*Dc)+2Crs+2Lr2+Wh+6mm, where Lc is the length of the battery matrix, Dc is the distance between two adjacent battery cells, Crs is the creepage distance of the short side, Lr2 is the lead-out length of the conductive material, and Wh is the width of the blank space in the middle; the value range of Crs is 10.4mm-39.5mm, the value range of Lr2 is 7mm-8mm, and the value range of Wh is 10mm-13mm.

8. The photovoltaic module according to claim 7, characterized in that: The module width Wm of the photovoltaic module is 6*Wc+Crl1+Crl2+Ds1+Ds2+Ds3+Ds4+Ds5+6mm, where Crl1 and Crl2 are the creepage distances of the long sides, and Ds1-Ds5 are the string spacings of the battery strings; 0.4mm≤Crl1≤18.5mm or 0.4mm≤Crl2≤18.5mm, and the difference between Crl1 and Crl2 is ≤2mm; the value ranges of Ds1, Ds2, Ds3, Ds4 and Ds5 are all 0.2mm-2.44mm.

9. The photovoltaic module according to claim 8, characterized in that: The difference between any two parameters of the string spacing Ds1, Ds2, Ds3, Ds4, and Ds5 of the battery string is ≤0.5, and Ds1 or Ds5≥Ds2 or Ds3 or Ds4, and Ds2 or Ds4≥Ds3.

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