CN219937054U

CN219937054U - Solar cell and photovoltaic module

Info

Publication number: CN219937054U
Application number: CN202321262252.2U
Authority: CN
Inventors: 陈振东; 王路闯; 陶武松; 石家乐
Original assignee: Zhejiang Jinko Solar Co Ltd; Jinko Solar Co Ltd
Current assignee: Zhejiang Jinko Solar Co Ltd; Jinko Solar Co Ltd
Priority date: 2023-05-23
Filing date: 2023-05-23
Publication date: 2023-10-31
Anticipated expiration: 2033-05-23
Also published as: DE202023104542U1

Abstract

The embodiment of the utility model relates to the field of photovoltaics, and provides a solar cell and a photovoltaic module, wherein the solar cell comprises: the substrate comprises X first areas, wherein an intermediate area is arranged between every two first areas, and X is more than or equal to 2 and less than or equal to 10; m grid lines which are sequentially arranged along a first direction, wherein each grid line is positioned on each first region; k electrical connection lines, any one of which is electrically connected with H gate lines near the end of the substrate or H gate lines near the middle region, where H satisfies: h is more than or equal to 2 and less than or equal to 12; the width range of the electric connection line is 8 um-60 um along the extending direction of the grid line; and along the first direction, the length range of the electric connection line is 2-50 mm. The solar cell and the photovoltaic module provided by the embodiment of the utility model can at least improve the yield of the photovoltaic module.

Description

Solar cell and photovoltaic module

Technical Field

The embodiment of the utility model relates to the field of photovoltaics, in particular to a solar cell and a photovoltaic module.

Background

Solar cells are devices that directly convert light energy into electrical energy through a photoelectric effect or a photochemical effect. The single solar cell cannot be directly used for power generation. Several single batteries must be connected in series and parallel by welding strips and tightly packaged into a module for use. Solar cell modules (also called solar panels) are the core part of and the most important part of a solar power generation system. The solar cell module is used for converting solar energy into electric energy, or sending the electric energy to a storage battery for storage, or pushing a load to work.

The battery piece is very fragile, and the upper and lower surfaces of the battery assembly are generally required to be provided with adhesive films and cover plates for protecting the battery piece. The cover plate is generally made of photovoltaic glass, the photovoltaic glass cannot be directly attached to the battery piece, and the adhesive film is required to be adhered in the middle. The connection between the battery cells typically requires a solder strip for collecting current, and conventional solder strips require alloying between the solder strip and the fine grid by welding during soldering. However, the melting point of the solder in the ribbon is generally high, and in the actual soldering process, the soldering temperature is 20 ℃ or higher than the melting point of the solder. The battery piece is large in buckling deformation in the welding process, so that the hidden cracking risk after welding is large, and the breaking rate is high. In the above background, low temperature solder strips and no main grid technology have been developed in order to improve the quality of the solder. There are many factors that affect the yield of the assembly, such as the effect of the solder between the solder strip and the fine grid, the yield of the solder, and the like.

Disclosure of Invention

The embodiment of the utility model provides a solar cell and a photovoltaic module, which are at least beneficial to improving the yield of the photovoltaic module.

According to some embodiments of the present utility model, an aspect of an embodiment of the present utility model provides a solar cell, including: the substrate comprises X first areas, wherein an intermediate area is arranged between every two first areas, and X is more than or equal to 2 and less than or equal to 10; m grid lines which are sequentially arranged along a first direction, wherein each grid line is positioned on each first region; k electrical connection lines, any one of which is electrically connected with H gate lines near the end of the substrate or H gate lines near the middle region, where H satisfies: h is more than or equal to 2 and less than or equal to 12; the width range of the electric connection line is 8 um-60 um along the extending direction of the grid line; and along the first direction, the length range of the electric connection line is 2-50 mm.

In some embodiments, each of the gate lines includes n+1 body portions and N break portions; further comprises: a reinforcing grid located at each of the disconnected portions and in electrical contact with the body portion; along the first direction, each electric connecting wire is opposite to each reinforcing grid; where k=x×2n.

In some embodiments, the length of the reinforcing grid along the first direction ranges from 0.015mm to 0.6mm, and the length of the reinforcing grid along the second direction ranges from 0.5mm to 4.5mm.

In some embodiments, further comprising: the passivation layer is positioned on the surface of the substrate, and the body part burns through the passivation layer; the reinforcing grid burns through the passivation layer; the electrical connection lines burn through the passivation layer.

In some embodiments, the N satisfies: n is more than or equal to 12 and less than or equal to 30.

In some embodiments, the substrate has a length in the first direction of 180mm to 220mm; the M within the same substrate satisfies: m is more than or equal to 100 and less than or equal to 200; the number M3 of the gate lines of the first region satisfies: m3 is more than or equal to 100/X and is more than or equal to 200/X.

In some embodiments, the substrate has opposite front and back sides; the gate line includes: a first number M1 of first fine gratings located on the front side of the substrate, the M1 satisfying: m1 is more than or equal to 100 and less than or equal to 180; a second number M2 of second fine gratings located on the back side of the substrate, the M2 being greater than M1, the M2 satisfying: m2 is more than or equal to 150 and less than or equal to 200.

In some embodiments, the width of the first fine gate along the first direction ranges from 10um to 17um; the width of the second fine grid is in the range of 14um to 20um along the first direction.

According to some embodiments of the present utility model, there is also provided an X-segmented solar cell according to another aspect of the embodiments of the present utility model, wherein X satisfies 2.ltoreq.X.ltoreq.10; comprising the following steps: a substrate; w electrodes sequentially arranged along a first direction, wherein each electrode is positioned on each substrate; 2N electrical connection lines, any one of which electrically connects H of the electrodes near the end of the substrate, the H satisfying: h is more than or equal to 2 and less than or equal to 12; along the extending direction of the electrode, the width range of the electric connection line is 8 um-60 um; and along the first direction, the length range of the electric connection line is 2-50 mm.

In some embodiments, each of the electrodes includes n+1 body portions and N break portions; further comprises: a reinforcing grid located at each of the disconnected portions and in electrical contact with the body portion; along the first direction, each electric connection wire is opposite to each reinforcing grid.

In some embodiments, the substrate has a length in the first direction of 180mm to 220mm; the W within the same substrate satisfies: W/X is more than or equal to 100 and less than or equal to 200/X.

According to some embodiments of the present utility model, another aspect of the embodiments of the present utility model further provides a photovoltaic module, including: a cell string formed by electrically connecting a plurality of solar cells according to any one of the above embodiments by solder strips, the solder strips being electrically connected to each grid line, the solder strips being in electrical contact with the reinforcing grid, and the solder strips being in electrical contact with the electrical connection lines; the packaging layer is used for covering the surface of the battery string; and the cover plate is used for covering the surface of the packaging layer, which is away from the battery strings.

The technical scheme provided by the embodiment of the utility model has at least the following advantages:

according to the technical scheme provided by the utility model, the end part of the battery piece is provided with the electric connecting wire, and the electric connecting wire is electrically connected with 2-12 grid lines close to the end part of the substrate or 2-12 grid lines close to the middle area, so that the electric connecting wire can improve the welding area between the battery piece and the welding strip, and the electric connecting wire can improve the welding tension between the battery piece and the welding strip, thereby improving the welding effect between the battery piece and the welding strip. The electrical connection lines connect only part of the grid lines, not all of the grid lines, so that the covering area of the surface of the substrate is small, and the cell efficiency of the solar cell is improved. The electrical connection lines are positioned at the ends of the substrate, which can improve the current collection capability of the ends of the substrate, thereby improving the battery efficiency.

In addition, the reinforcing grid is arranged in the solar cell, and the welding tension between the grid line and the welding strip can be increased by the reinforcing grid, so that the welding effect between the grid line and the welding strip is improved. An electric connection wire is arranged in the solar cell, and the electric connection wire can collect current of the thin grid close to the end part and the middle area of the cell, so that the problem of damage caused by the fact that the welding strip is positioned at the end part can be avoided.

Drawings

One or more embodiments are illustrated by way of example and not limitation in the figures of the accompanying drawings, which are not to be construed as limiting the embodiments unless specifically indicated otherwise; in order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the conventional technology, the drawings required for the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present utility model, and other drawings may be obtained according to the drawings without inventive effort for those skilled in the art.

Fig. 1 is a schematic structural diagram of a solar cell according to an embodiment of the present utility model;

FIG. 2 is a schematic view of a first cross-sectional structure of FIG. 1 along the line A1-A2;

FIG. 3 is a schematic view of a first cross-sectional structure of the cross-section B1-B2 of FIG. 1;

FIG. 4 is a schematic view of a first cross-sectional structure of FIG. 1 along the line C1-C2;

FIG. 5 is a schematic view of a second cross-sectional structure taken along the line C1-C2 in FIG. 1;

FIG. 6 is a schematic view of a second cross-sectional structure of FIG. 1 along the line A1-A2;

FIG. 7 is a schematic view of a third cross-sectional structure of FIG. 1 along the line A1-A2;

fig. 8 is a schematic view of a first partial structure of an electrical connection line of a solar cell according to an embodiment of the present utility model;

FIG. 9 is a schematic view of a first partial structure of a reinforcement grid of a solar cell according to an embodiment of the present utility model;

fig. 10 is a schematic view of a second partial structure of a reinforcing grid of a solar cell according to an embodiment of the present utility model;

FIG. 11 is a schematic view of a third partial structure of a reinforcement grid of a solar cell according to an embodiment of the present utility model;

fig. 12 is a schematic view of a fourth partial structure of a reinforcing grid of a solar cell according to an embodiment of the present utility model;

fig. 13 is a schematic view of a first partial structure of a solar cell according to an embodiment of the present utility model;

fig. 14 is a schematic view of a second partial structure of a solar cell according to an embodiment of the present utility model;

fig. 15 is a schematic view of another structure of a solar cell according to an embodiment of the present utility model;

fig. 16 is a schematic structural diagram of a photovoltaic module according to an embodiment of the present utility model;

fig. 17 is a schematic view of a first structure of forming a solder strip in a photovoltaic module according to an embodiment of the present utility model;

fig. 18 is a schematic view of a second structure of forming a solder strip in a photovoltaic module according to an embodiment of the utility model.

Detailed Description

As known from the background art, the yield of the current photovoltaic module is poor.

In the solar cell provided by the utility model, the end part of the cell is provided with the electric connecting wire, and the electric connecting wire is electrically connected with 2-12 grid lines close to the end part of the substrate or 2-12 grid lines close to the middle area, so that the electric connecting wire can improve the welding area between the cell and the welding strip, and the electric connecting wire can improve the welding tension between the cell and the welding strip, thereby improving the welding effect between the cell and the welding strip. The electrical connection lines connect only part of the grid lines, not all of the grid lines, so that the covering area of the surface of the substrate is small, and the cell efficiency of the solar cell is improved. The electrical connection lines are positioned at the ends of the substrate, which can improve the current collection capability of the ends of the substrate, thereby improving the battery efficiency.

Embodiments of the present utility model will be described in detail below with reference to the attached drawings. However, it will be understood by those of ordinary skill in the art that in various embodiments of the present utility model, numerous specific details are set forth in order to provide a thorough understanding of the present utility model. However, the claimed technical solution of the present utility model can be realized without these technical details and various changes and modifications based on the following embodiments.

Fig. 1 is a schematic structural diagram of a solar cell according to an embodiment of the present utility model; FIG. 2 is a schematic view of a first cross-sectional structure of FIG. 1 along the line A1-A2; FIG. 3 is a schematic view of a first cross-sectional structure of the cross-section B1-B2 of FIG. 1; FIG. 4 is a schematic view of a first cross-sectional structure of FIG. 1 along the line C1-C2; FIG. 5 is a schematic view of a second cross-sectional structure taken along the line C1-C2 in FIG. 1; FIG. 6 is a schematic view of a second cross-sectional structure of FIG. 1 along the line A1-A2; FIG. 7 is a schematic view of a third cross-sectional structure of FIG. 1 along the line A1-A2; fig. 8 is a schematic view of a first partial structure of an electrical connection line of a solar cell according to an embodiment of the present utility model; FIG. 9 is a schematic view of a first partial structure of a reinforcement grid of a solar cell according to an embodiment of the present utility model; fig. 10 is a schematic view of a second partial structure of a reinforcing grid of a solar cell according to an embodiment of the present utility model; FIG. 11 is a schematic view of a third partial structure of a reinforcement grid of a solar cell according to an embodiment of the present utility model; fig. 12 is a schematic view of a fourth partial structure of a reinforcing grid of a solar cell according to an embodiment of the present utility model; fig. 13 is a schematic view of a first partial structure of a solar cell according to an embodiment of the present utility model; fig. 14 is a schematic view of a second partial structure of a solar cell according to an embodiment of the utility model. In order to illustrate the relative positional relationship among the electrical connection lines, the reinforcing grid, and the bonding pads, the bonding pads are also illustrated in fig. 2, 4, and 7.

It will be appreciated that fig. 2 to 7 only show the positional relationship of the film layers on the front surface of the substrate, and the cross-sectional view of the back surface is not shown here, and the positional relationship of the film layers on the back surface may be the same or different as the film layers on the front surface.

Referring to fig. 1 to 14, according to some embodiments of the present utility model, an aspect of an embodiment of the present utility model provides a solar cell, including: a substrate 100, the substrate 100 comprising X first regions 10, each first region 10 having an intermediate region 20 therebetween, X satisfying 2.ltoreq.X.ltoreq.10; m gate lines 21 sequentially arranged along the first direction Y, each gate line 21 being located on each first region 10; k electrical connection lines 101, where any one electrical connection line 101 electrically connects H gate lines 21 near the end of the substrate 100 or H gate lines 21 near the intermediate region 20, H satisfies: h is more than or equal to 2 and less than or equal to 12.

In some embodiments, H satisfies 2-4, 4-6, 6-8, 8-10, or 10-12.

The solar cell may be any one of conventional TOPCON (Tunnel Oxide Passivated Contact, tunnel oxide passivation contact) cells, PERC cells (passivation emitter and back cells, passivated emitter and real cell), heterojunction cells, and the like. In some embodiments, the solar cell may also be a compound cell, including but not limited to silicon germanium, silicon carbide, gallium arsenide, indium gallium, perovskite, cadmium telluride, copper indium selenium, and the like.

The solar cell includes a substrate and a passivation layer sequentially stacked. The material of the substrate 100 may be an elemental semiconductor material. Specifically, the elemental semiconductor material is composed of a single element, which may be silicon or silicon, for example. The elemental semiconductor material may be in a single crystal state, a polycrystalline state, an amorphous state, or a microcrystalline state (a state having both a single crystal state and an amorphous state, referred to as a microcrystalline state), and for example, silicon may be at least one of single crystal silicon, polycrystalline silicon, amorphous silicon, or microcrystalline silicon.

In some embodiments, the material of the substrate 100 may also be a compound semiconductor material. Common compound semiconductor materials include, but are not limited to, silicon germanium, silicon carbide, gallium arsenide, indium gallium, perovskite, cadmium telluride, copper indium selenium, and the like. The substrate 100 may also be a sapphire substrate, a silicon-on-insulator substrate, or a germanium-on-insulator substrate.

In some embodiments, the substrate 100 may be an N-type semiconductor substrate or a P-type semiconductor substrate. The N-type semiconductor substrate is doped with an N-type doping element, which may be any of v group elements such As phosphorus (P) element, bismuth (Bi) element, antimony (Sb) element, and arsenic (As) element. The P-type semiconductor substrate is doped with a P-type element, and the P-type doped element may be any one of group iii elements such as boron (B) element, aluminum (Al) element, gallium (Ga) element, and gallium (In) element.

In some embodiments, the solar cell further comprises: passivation layer 103, passivation layer 103 is located on the surface of substrate 100. The material of the passivation layer 103 includes any one or more of silicon oxide, silicon nitride, silicon oxynitride, silicon oxycarbonitride, titanium oxide, hafnium oxide, and aluminum oxide.

The solar cell includes an emitter electrode on the front surface of the substrate 100 and a first passivation layer, a second passivation layer on the back surface of the substrate 100, and a gate line electrically contacting the emitter electrode through the first passivation layer and the gate line electrically contacting the back surface through the thickness of the second passivation layer. The passivation layer 103 includes a first passivation layer and a second passivation layer.

In some embodiments, when the solar cell is a TOPCON cell, the solar cell may further include a tunneling dielectric layer and a doped conductive layer stacked, the tunneling dielectric layer being located on the back side of the substrate 100, the gate line burning through the second passivation layer and making electrical contact with the doped conductive layer.

In some embodiments, the grids 21 are all sub-grids of the solar cell, and the sub-grids can be sintered by burning-through paste. The method of forming the gate line 21 includes: and printing metal paste on the surface of part of the passivation layer by adopting a screen printing process. The metal paste may include at least one of silver, rate, copper, tin, gold, lead, or nickel. The metal paste is subjected to a sintering process, in some embodiments, a material having a highly corrosive component such as glass therein, such that the corrosive component will corrode the passivation layer during the sintering process, thereby allowing the metal paste to penetrate in the passivation layer 103 to make electrical contact with the substrate 100.

In some embodiments, the gate lines 21 include a plurality of first gate lines 110 positioned in electrical contact with the electrical connection lines 101 and a plurality of second gate lines 120 not in electrical contact with the electrical connection lines 101 along the first direction Y.

In some embodiments, the material of the electrical connection line 101 is the same as the material of the first gate line 110, and the electrical connection line 101 is prepared in the same printing process as the first gate line 110.

In some embodiments, the first length L1 of the electrical connection line 101 along the extending direction X of the gate line 21 ranges from 8um to 60um. The first length L1 may be 8 to 20, 20 to 35, 35 to 50, 50 to 60, 28 to 55, 13 to 52, or 22 to 45um. The first length L1 may be 10.3um, 21.8um, 32.7um, 43.6um, 55.8um, or 60um.

In some embodiments, the first width W1 of the electrical connection line 101 along the first direction Y ranges from 2mm to 50mm. The first width W1 may be 2mm to 10mm, 10mm to 20mm, 20mm to 30mm, 30mm to 40mm, 40mm to 50mm, 16mm to 28mm, or 19mm to 50mm. The first width W1 may be 2mm, 18mm, 21mm, 33mm, 35mm, 42mm, 46mm or 50mm.

In some embodiments, each gate line 21 includes a second gate line 120, the second gate line 120 including: n+1 main body portions 121 and N disconnecting portions 122; further comprises: a reinforcing gate 102, the reinforcing gate 102 being located at each of the breaking portions 122 and being in electrical contact with the body portion 121; along the first direction, each electrical connection line 101 is opposite to each reinforcing grid 102; where k=x×2n. The break 122 refers to a discontinuity between adjacent body portions 121, i.e., no metal paste is printed in the area between the body portions 121, thereby causing a discontinuity in the area between the body portions 121.

In some embodiments, the length L4 of the breaking portion 122 along the first direction Y ranges from 0.05mm to 1.3mm, and the breaking portion 122 may ensure that the area contacted by the solder strip 40 is the reinforcing grid 102, so as to improve the problem of cold joint between the solder strip and the grid line; when the length L4 of the breaking portion 122 along the first direction Y is greater than 1.3mm, the breaking distance is too large, which may affect the second gate line 120 to collect the current generated by the photoelectric effect; when the length L4 of the breaking portion 122 in the first direction Y is less than 0.05mm, the area of the reinforcing grid 102 is small, so that the problem of small welding tension between the battery cell and the welding strip cannot be improved.

In some embodiments, the two ends of the reinforcing grid 102 are in electrical contact with the body portion 121, respectively. The reinforcing grid 102 is in electrical contact with the solder strip 40, thereby increasing the solderability between the battery tab and the solder strip 40.

In some embodiments, the printing paste of the reinforcing grid 102 is different from the printing paste of the body portion 121, the printing paste of the reinforcing grid 102 is the same as the printing paste of the main grid line, and the reinforcing grid 102 does not penetrate the thickness of the passivation layer 103 and is in electrical contact with the body portion 121. In this way, the contact performance between the reinforcing grid 102 and the solder strip 40 is better, and the material of the reinforcing grid 102 is the printing paste of the main grid line, and the printing paste of the main grid line has less silver-containing component, so that the preparation cost can be reduced. Second, the reinforcing grid 102 does not need to burn through the passivation layer 103, and the sintering process time can be reduced to reduce thermal damage to the battery cells.

In some embodiments, along the second direction X, the sides of the reinforcing grid 102 are in electrical contact with the body portion 121. The side surfaces of the reinforcing grid 102 are in electrical contact with the side surfaces of the body portion 121. In some embodiments, along the thickness direction of the grid line 21, one of the upper and lower top surfaces of the reinforcing grid 102 is in electrical contact with the body portion 121, which increases the contact area between the body portion 121 and the reinforcing grid 102, and also reduces the misalignment problem during overprinting of the body portion 121 and the reinforcing grid 102, thereby improving the yield of the battery.

In some embodiments, the length W2 of the reinforcing grid 102 in the first direction ranges from 0.015mm to 0.6mm, and the length L2 of the reinforcing grid 102 in the second direction X ranges from 0.5mm to 4.5mm. The length L2 of the reinforcing grid 102 can ensure the alignment area between the solder strip 40 and the reinforcing grid 102, and ensure that the contact area between the solder strip 40 and the battery piece is the reinforcing grid 102, thereby improving the contact area and the contact performance between the battery piece and the solder strip 40. The length of the reinforcing grid 102 is also not too long, thereby reducing the area of the cell for collecting current and reducing cell efficiency.

In some embodiments, referring to fig. 11, the reinforcing grid 102 includes a first portion 33 along the second direction X and a second portion 32, the first portion 33 being in contact with the body portion 121, the second portion 32 being for contact with the solder strip 40. The third width W3 of the end of the first portion 33 away from the second portion 32 is greater than the fourth width W4 of the contact surface between the first portion 33 and the second portion 32, and when the second grid lines 120 are overprinted for the second time, the first portion 33 with the greater third width W3 can ensure that the deviation range between each second grid line 120 and the reinforcing grid 102 is enlarged, thereby improving the yield of the battery. In addition, the difference between the third width W3 and the fourth width W4 allows the side surface of the first portion 33 in the first direction Y to serve as a guide groove, reducing the shielding area of the reinforcing grid 102 while improving the success rate of alignment between the second grid line 120 and the reinforcing grid 102.

In some embodiments, the length L7 of the second portion 32 ranges from 0.01mm L7 to 1.5mm. L7 may range from 0.01mm to 0.17mm, from 0.18mm to 1.31mm, from 0.23mm to 1.5mm, from 0.88mm to 1.48mm, from 0.5mm to 1.1mm, from 0.6mm to 1.27mm, or from 0.09mm to 0.92mm. L7 may be 0.01mm, 0.29mm, 0.38mm, 0.76mm, 1.02mm, 1.16mm, 1.29mm, 1.41mm or 1.5mm.

In some embodiments, the length L8 of the first portion 33 ranges from 0.05mm L8 to 1.5mm. L8 may range from 0.06mm to 0.17mm, from 0.2mm to 1.38mm, from 0.25mm to 1.48mm, from 0.93mm to 1.42mm, from 0.46mm to 1.12mm, from 0.7mm to 1.8mm, or from 0.14mm to 1.45mm. L8 may be 0.05mm, 0.28mm, 0.41mm, 0.86mm, 1.08mm, 1.14mm, 1.24mm, 1.43mm or 1.5mm.

In some embodiments, the third width W3 ranges from 0.02 mm.ltoreq.W3.ltoreq.1.5 mm. The third width W3 may range from 0.02mm to 0.8mm, from 0.18mm to 1.39mm, from 0.2mm to 1.5mm, from 0.9mm to 1.48mm, from 0.5mm to 1mm, from 0.6mm to 1.3mm, or from 0.09mm to 0.8mm. The third width W3 may be 0.06mm, 0.58mm, 0.77mm, 0.98mm, 1.19mm, 1.28mm, 1.33mm, 1.42mm, or 1.5mm.

The fourth width W4 is in the range of 0.02mm < W2 < 2mm. The fourth width W4 may range from 0.02mm to 1.21mm, from 0.18mm to 1.68mm, from 0.2mm to 1.97mm, from 0.9mm to 1.59mm, from 0.5mm to 1.31mm, from 0.6mm to 1.38mm, or from 0.09mm to 0.94mm. The fourth width W4 may be 0.06mm, 0.78mm, 1.22mm, 1.58mm, 1.67mm, 1.78mm, 1.87mm, 1.92mm, or 2mm.

In some embodiments, referring to fig. 11, the partial length L3 of the overlap region between reinforcing grid 102 and body portion 121 ranges from 0.05mm to 1.5mm. L3 may range from 0.06mm to 0.17mm, from 0.2mm to 1.38mm, from 0.25mm to 1.48mm, from 0.93mm to 1.42mm, from 0.46mm to 1.12mm, from 0.7mm to 1.8mm, or from 0.14mm to 1.45mm. L3 may be 0.05mm, 0.28mm, 0.41mm, 0.86mm, 1.08mm, 1.14mm, 1.24mm, 1.43mm or 1.5mm. W1

In some embodiments, referring to fig. 12, the solar cell further comprises: auxiliary pads 105, the auxiliary pads 105 being located on both sides of the reinforcing grid 102, and a part of the length of the auxiliary pads 102 overlapping and electrically contacting the body 121. The auxiliary welding spot 105 and the reinforcing grid 102 are of an integrated structure, and the auxiliary welding spot 105 is also prepared from printing paste of the main grid line.

In some embodiments, the auxiliary welding spot 105 is used to improve accuracy of alignment between the reinforcing grid 102 and the second grid line 120, and avoid offset and dislocation between the second grid line 120 and the reinforcing grid 102, so that problems such as excessive contact resistance or grid breakage between the second grid line 120 and the reinforcing grid 102 are caused. The auxiliary welding spot 105 is further used for improving the contact area between the reinforcing grid 102 and the second grid line 120, so as to ensure the connection performance between the reinforcing grid 102 and the second grid line 120, further ensure the welding performance between the welding strip 40 and the battery piece, and avoid the off-welding between the welding strip 40 and the battery piece.

In some embodiments, the body portion 121 is in electrical contact with a portion of the top surface of the auxiliary pad 105 in the thickness direction of the second gate line 120; alternatively, the body portion 121 is in electrical contact with a portion of the bottom surface of the auxiliary pad 105. The contact area between the auxiliary welding spot 105 and the body portion 121 is increased as compared with the side-to-side electrical contact between the body portion 121 and the auxiliary welding spot 105 in the second direction X, thereby reducing the contact resistance between the body portion 121 and the auxiliary welding spot 105 and further improving the battery efficiency.

In some embodiments, the width of the auxiliary welding spot 105 is greater than the width of the body portion 121 along the first direction Y. The auxiliary welding spots 105 have a larger width, and when the auxiliary welding spots 105 are printed and the body 121 is overprinted, the auxiliary welding spots 105 having a larger width can ensure that the deviation range between each second grid line 120 and the reinforcing grid 102 is enlarged, thereby improving the yield of the battery piece.

The value illustrates that the width of the auxiliary welding spot 105 is larger than the width of the second grid line 120, but is not excessively large, so that the shielding area of the solar cell sheet is reduced, and the cell efficiency is improved.

In some embodiments, the auxiliary welding spot 105 may be in a trapezoid shape as shown in fig. 12, and the embodiment of the present utility model does not specifically limit the shape of the auxiliary welding spot, but only needs to ensure that the width of the auxiliary welding spot is greater than the width of the second gate line.

In some embodiments, referring to FIG. 12, the length L5 of the auxiliary welding spot 105 in the second direction X ranges from 0.05mm L5 to 1.5mm. The length of L5 is used to ensure a contact area between the second gate line 120 and the auxiliary pad 105.

In some embodiments, the length of the portion where the auxiliary welding spot 105 and the body portion 121 overlap each other is L5, satisfying 0.05 mm.ltoreq.L5.ltoreq.1.5 mm. The length of the auxiliary pad 105 overlapping the body 121 is L5, and since the reinforcing gate 102 is also in electrical contact with the first gate line 22, the length of the auxiliary pad 105 in the second direction X is equal to the length of the portion of the auxiliary pad 105 overlapping the body 121.

In some embodiments, the width of the side of the auxiliary welding spot 105 away from the reinforcing grid 102 along the first direction Y is a fifth width W5, the width of the contact surface of the auxiliary welding spot 105 with the reinforcing grid 102 along the first direction Y is a seventh width W7, and the fifth width W5 is greater than the seventh width W7. In this way, when the second grid lines 120 are overprinted for the second time, the auxiliary welding spots 105 with larger fifth width W5 can ensure that the deviation range between each second grid line 120 and the reinforcing grid 102 is enlarged, thereby improving the yield of the battery piece. In addition, the difference between the fifth width W5 and the seventh width W7 allows the side of the auxiliary welding spot 105 in the first direction Y to serve as a guide groove, reducing the shielding area of the auxiliary welding spot 105 and improving the success rate of alignment between the second grid line 120 and the reinforcing grid 102.

In some embodiments, the fifth width W5 ranges from 0.02 mm.ltoreq.W5.ltoreq.1.5 mm. The fifth width W5 may range from 0.02mm to 0.8mm, from 0.18mm to 1.39mm, from 0.2mm to 1.5mm, from 0.9mm to 1.48mm, from 0.5mm to 1mm, from 0.6mm to 1.3mm, or from 0.09mm to 0.8mm. The fifth width W5 may be 0.06mm, 0.58mm, 0.77mm, 0.98mm, 1.19mm, 1.28mm, 1.33mm, 1.42mm, or 1.5mm.

The seventh width W7 is in the range of 0.02 mm.ltoreq.W7.ltoreq.2mm. The seventh width W7 may range from 0.02mm to 1.122mm, from 0.18mm to 1.68mm, from 0.2mm to 1.97mm, from 0.9mm to 1.59mm, from 0.5mm to 1.105mm, from 0.6mm to 1.38mm, or from 0.09mm to 0.94mm. The seventh width W7 may be 0.06mm, 0.78mm, 1.22mm, 1.58mm, 1.67mm, 1.78mm, 1.87mm, 1.92mm, or 2mm.

In some embodiments, N satisfies: n is more than or equal to 12 and less than or equal to 30.N is 12-16, 16-18, 18-20, 20-22, 22-24, 24-28 or 28-30. The number of reinforcing bars 102 is equal to the number of bonding pads 40 of the subsequent bonding process.

In some embodiments, the length of the substrate 100 in the first direction is 180mm to 220mm; m within the same substrate 100 satisfies: m is more than or equal to 100 and less than or equal to 200; the number M3 of gate lines of the first region 10 satisfies: m3 is more than or equal to 100/X and is more than or equal to 200/X.

In some embodiments, the length of the substrate 100 in the first direction is 180mm to 189mm, 189mm to 193mm, 193mm to 201mm, 201mm to 211mm, or 211mm to 200mm.

In some embodiments, M satisfies 100-120, 120-140, 140-160, 160-180, or 180-200.

In some embodiments, the substrate 100 has opposite front and back sides; the gate line 21 includes: a first number M1 of first fine gratings located on the front surface of the substrate 100, M1 satisfying: m1 is more than or equal to 100 and less than or equal to 180; a second number M2 of second fine gates located on the back side of the substrate 100, M2 being greater than M1, M2 satisfying: m2 is more than or equal to 150 and less than or equal to 200.

In some embodiments, M1 satisfies: 100 to 118, 118 to 139, 139 to 158 or 158 to 180. M2 satisfies the following: 150-168, 168-179, 179-188 or 188-200.

In some embodiments, the width of the first fine gate along the first direction Y ranges from 10um to 45um. The width of the first fine grid may be 11um to 15um, 15um to 20um, 20um to 38um, 38um to 45um, 10um to 25um, 18um to 32um, or 14um to 37um. The width of the first fine gate may be 10.3um, 16.8um, 21.7um, 33.6um, 35.8um, 41.1um, 42.3um, or 45um.

In some embodiments, the width of the second fine gate along the first direction Y ranges from 14um to 60um. The width of the second fine grid may range from 15um to 20um, from 20um to 28um, from 28um to 35um, from 35um to 49um, from 49um to 52um, from 52um to 60um, or from 18um to 39um. The width of the second fine gate may range from 14.3um, 24.8um, 35.7um, 41.8um, 47.8um, 52.1um, 59.6um, or 60um.

The width of the body 121 in the first direction Y in fig. 10 and 9 is equal to the width of the first gate line 110 in fig. 8, so the same reference numerals are used for the sixth width W6, and the sixth width W6 may be the ninth width of the first fine gate or the tenth width of the second fine gate. In some embodiments, the width of the body portion 121 in the first direction Y in fig. 9 may be different from the width of the first gate line 110 in fig. 8.

In some embodiments, referring to fig. 14, the gate lines further include a third gate line 130 at an end of the substrate and not in contact with the electrical connection line. The number of the third gate lines 130 may be 1 to 2, 2 to 4, 4 to 6, 1 to 6, or 2 to 4.

Correspondingly, the embodiment of the utility model also provides a solar cell formed by dicing the solar cell provided by the first embodiment, wherein one cell piece is divided into X cell pieces along the middle area, and X is more than or equal to 2 and less than or equal to 10; the same elements as those of the above embodiment are not described again here. Fig. 15 is a schematic view of another structure of a solar cell according to an embodiment of the utility model. Wherein the electrode and the gate line are the same element, the same reference numeral 21 is used here.

According to some embodiments of the present utility model, in another aspect, there is provided an X-segmented solar cell, wherein X satisfies 2.ltoreq.x.ltoreq.10; referring to fig. 15, the solar cell includes: a substrate 100; w electrodes sequentially arranged along the first direction, wherein each electrode is positioned on each substrate; 2N electrical connection lines, any one of which electrically connects H electrodes near the end of the substrate, H satisfying: h is more than or equal to 2 and less than or equal to 12; along the extending direction of the electrode, the width range of the electric connection line is 8 um-60 um; the length of the electrical connection line along the first direction ranges from 2mm to 50mm.

In some embodiments, each electrode includes n+1 body portions and N break portions; further comprises: a reinforcing grid located at each of the breaking portions and in electrical contact with the body portion; along the first direction, each electric connection line is opposite to each reinforcing grid.

In some embodiments, N satisfies: n is more than or equal to 12 and less than or equal to 30.

In some embodiments, the length of the substrate in the first direction is 180mm to 220mm; w within the same substrate satisfies: W/X is more than or equal to 100 and less than or equal to 200/X.

In one example, X is 2, and W within the same substrate satisfies: w is more than or equal to 50 and less than or equal to 100.W satisfies 50-60, 60-70, 70-80, 80-90 or 90-100.

Accordingly, according to some embodiments of the present utility model, another aspect of the embodiments of the present utility model further provides a photovoltaic module, and the elements that are the same as those of the foregoing embodiments are not described herein again.

Fig. 16 is a schematic structural diagram of a photovoltaic module according to an embodiment of the present utility model; fig. 17 is a schematic view of a first structure of forming a solder strip in a photovoltaic module according to an embodiment of the present utility model; fig. 18 is a schematic view of a second structure of forming a solder strip in a photovoltaic module according to an embodiment of the utility model.

Referring to fig. 16 to 18, the photovoltaic module includes: a cell string formed by electrically connecting a plurality of solar cells 50 according to any one of the above embodiments through solder ribbons 40, the solder ribbons 40 being electrically connected to each grid line 21, the solder ribbons 40 being in electrical contact with the reinforcing grid 102, and the solder ribbons 40 being in electrical contact with the electrical connection lines 101; an encapsulation layer 51 for covering the surface of the battery string; a cover plate 52 for covering the surface of the encapsulation layer 51 facing away from the battery string.

Specifically, in some embodiments, the plurality of battery strings may be electrically connected by a solder strip 40. Fig. 16 only illustrates a positional relationship between solar cells 50, that is, electrodes of the solar cells 50 having the same polarity are arranged in the same direction or electrodes having positive polarity of each cell are arranged toward the same side, so that conductive strips connect different sides of two adjacent cells, respectively. In some embodiments, the solar cells 50 may also be arranged in order of the electrodes with different polarities facing the same side, i.e. the electrodes of the adjacent plurality of cells are sequentially ordered according to the order of the first polarity, the second polarity, and the first polarity, so that the conductive strip connects two adjacent cells on the same side.

In some embodiments, no space is provided between the solar cells 50, i.e., the solar cells 50 overlap each other.

In some embodiments, the encapsulation layer 51 includes a first encapsulation layer covering one of the front side or the back side of the solar cell 50 and a second encapsulation layer covering the other of the front side or the back side of the solar cell 50, and specifically, at least one of the first encapsulation layer or the second encapsulation layer may be an organic encapsulation film such as a polyvinyl butyral (Polyvinyl Butyral, abbreviated as PVB) film, an ethylene-vinyl acetate copolymer (EVA) film, a polyethylene octene co-elastomer (POE) film, or a polyethylene terephthalate (PET) film.

It will be appreciated that the first and second encapsulant layers also have demarcations before lamination, and that the formation of the photovoltaic module after lamination process does not have the concept of the first and second encapsulant layers, which already form the integral encapsulant layer 51.

In some embodiments, the cover plate 52 may be a glass cover plate, a plastic cover plate, or the like having a light-transmitting function. Specifically, the surface of the cover plate 52 facing the encapsulation layer 51 may be a concave-convex surface, thereby increasing the utilization rate of incident light. The cover plate 52 includes a first cover plate opposite the first encapsulation layer and a second cover plate opposite the second encapsulation layer.

It will be understood by those of ordinary skill in the art that the foregoing embodiments are specific examples of carrying out the utility model and that various changes in form and details may be made therein without departing from the spirit and scope of the utility model. Various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the utility model, and the scope of the utility model should be assessed accordingly to that of the appended claims.

Claims

1. A solar cell, comprising:

a substrate comprising X first regions, each of which has an intermediate region between two of the first regions, wherein X satisfies 2.ltoreq.

X≤10；

M grid lines which are sequentially arranged along a first direction, wherein each grid line is positioned on each first region;

k electrical connection lines, any one of which is electrically connected with H gate lines near the end of the substrate or H gate lines near the middle region, where H satisfies: h is more than or equal to 2 and less than or equal to 12;

the width range of the electric connection line is 8 um-60 um along the extending direction of the grid line; and along the first direction, the length range of the electric connection line is 2-50 mm.

2. The solar cell of claim 1, wherein each of the grid lines comprises n+1 body portions and N break portions; further comprises: a reinforcing grid located at each of the disconnected portions and in electrical contact with the body portion;

along the first direction, each electric connecting wire is opposite to each reinforcing grid; where k=x×2n.

3. The solar cell according to claim 2, wherein the length of the reinforcing grid in the first direction ranges from 0.015mm to 0.6mm, and the length of the reinforcing grid in the second direction ranges from 0.5mm to 4.5mm.

4. The solar cell of claim 2, further comprising: the passivation layer is positioned on the surface of the substrate, and the body part burns through the passivation layer; the reinforcing grid burns through the passivation layer; the electrical connection lines burn through the passivation layer.

5. The solar cell according to claim 2, wherein N satisfies: n is more than or equal to 12 and less than or equal to 30.

6. The solar cell of claim 1, wherein the substrate has a length in the first direction of 180mm to 220mm; the M within the same substrate satisfies: m is more than or equal to 100 and less than or equal to 200; the number M3 of the gate lines of the first region satisfies: m3 is more than or equal to 100/X and is more than or equal to 200/X.

7. The solar cell of claim 1, wherein the substrate has opposite front and back sides; the gate line includes: a first number M1 of first fine gratings located on the front side of the substrate, the M1 satisfying: m1 is more than or equal to 100 and less than or equal to 180; a second number M2 of second fine gratings located on the back side of the substrate, the M2 being greater than M1, the M2 satisfying: m2 is more than or equal to 150 and less than or equal to 200.

8. The solar cell of claim 7, wherein the width of the first fine grid along the first direction ranges from 10um to 17um; the width of the second fine grid is in the range of 14um to 20um along the first direction.

9. An X-piece solar cell is characterized in that X is more than or equal to 2 and less than or equal to 10; comprising the following steps:

a substrate;

w electrodes sequentially arranged along a first direction, wherein each electrode is positioned on each substrate;

2N electrical connection lines, any one of which electrically connects H of the electrodes near the end of the substrate, the H satisfying: h is more than or equal to 2 and less than or equal to 12;

along the extending direction of the electrode, the width range of the electric connection line is 8 um-60 um; and along the first direction, the length range of the electric connection line is 2-50 mm.

10. The solar cell of claim 9, wherein each of the electrodes comprises n+1 body portions and N disconnection portions; further comprises: a reinforcing grid located at each of the disconnected portions and in electrical contact with the body portion;

along the first direction, each electric connection wire is opposite to each reinforcing grid.

11. The solar cell of claim 10, wherein N satisfies: n is more than or equal to 12 and less than or equal to 30.

12. The solar cell of claim 10, wherein the substrate has a length in the first direction of 180mm to 220mm; the W within the same substrate satisfies: W/X is more than or equal to 100 and less than or equal to 200/X.

13. A photovoltaic module, comprising:

a cell string formed by electrically connecting a plurality of solar cells according to any one of claims 1 to 12 by solder strips, the solder strips being electrically connected to each grid line, the solder strips being in electrical contact with the reinforcing grid and the solder strips being in electrical contact with the electrical connection lines;

the packaging layer is used for covering the surface of the battery string;

and the cover plate is used for covering the surface of the packaging layer, which is away from the battery strings.