AT17501U2 - Photovoltaic cell and photovoltaic module - Google Patents

Abstract

The present disclosure relates to a photovoltaic cell and a photovoltaic module. The photovoltaic cell comprises a substrate, a passivation layer arranged on at least one surface of the substrate, at least one busbar (1) and at least one finger (2), each of which intersects on the surface of the substrate, and at least one soldering pad (3 ) arranged on a surface of the substrate. The at least one busbar (1) is electrically connected to the at least one finger (2). The number of soldering pads (3) is 2 to 6. The at least one soldering pad (3) comprises first soldering pads (31), and the first soldering pads (31) are arranged at two ends of one of the at least one busbar (1). A number of at least one busbar (1) is greater than or equal to 11, and the at least one busbar each has a width of 20 μm to 80 μm. The at least one finger each has a width of 20 μm to 80 μm, and the number of fingers is 70 to 160. The at least one first soldering pad (31) each has a length and a width in a range from 0.3 mm to 1.2 mm on. This design can reduce the shielding of the substrate and facilitate the light absorption of the photovoltaic cell. At the same time, increasing the number of busbars and reducing the current flowing through a single busbar can reduce internal losses, and reducing the area of the solder pad can reduce silver paste consumption and help reduce costs, to more closely meet actual usage needs. .

Description

description

PHOTOVOLTAIC CELL AND PHOTOVOLTAIC MODULE

TECHNICAL AREA

[0001] The present disclosure relates to the field of solar energy technology and more particularly to a photovoltaic cell and a photovoltaic module.

BACKGROUND

[0002] With the development of technologies, solar devices such as solar panels have become widely used clean energy supply devices around the world. As a rule, a photovoltaic module includes a photovoltaic cell string that is formed from photovoltaic cells that are connected to one another via an electrode line. A soldering pad is arranged at a soldering point on a busbar of a solar cell in order to improve the stability of the soldering. However, the solder joint can shield a surface of the photovoltaic cell, thereby affecting the light absorption of the photovoltaic cell and thus the efficiency of the photovoltaic cell.

SUMMARY

[0003] The present disclosure relates to a photovoltaic cell and a photovoltaic module.

[0004] Embodiments of the present disclosure relate to a photovoltaic cell. The photovoltaic cell includes a substrate, a passivation layer disposed on at least one surface of the substrate, busbars and fingers each intersecting on the surface of the substrate, and solder pads disposed on a surface of the substrate. The busbars are electrically connected to the fingers. A number of the soldering pads is 2 to 6. The soldering pads include first soldering pads, and the first soldering pads are arranged at two ends of one of the busbars. A number of the busbars is greater than or equal to 11, and the busbars each have a width of 20 µm to 80 µm. The fingers each have a width of 20 µm to 80 µm, and the number of fingers is 70 to 160. The first soldering pads each have a length and a width in a range of 0.3 mm to 1.2 mm.

In one embodiment, the soldering pads further include second soldering pads, the second soldering pads are arranged between the first soldering pads, and the second soldering pads each have a length and a width in a range of 0.4 mm to 0.8 mm.

In one embodiment, the busbars and/or the fingers each have a dimension less than or equal to 10 µm along a thickness direction of the photovoltaic cell, and/or the first solder pads and/or the second solder pads each have a dimension less than than or equal to 8 µm along the thickness direction of the photovoltaic cell.

In one embodiment, the first soldering pads and/or the second soldering pads each have a shape of a rectangle, a rhombus, a circle, an ellipse or combinations thereof.

In one embodiment, the second soldering pad has an area in a range of 0.1 mm? up to 0.7 mm? on.

In one embodiment, the first soldering pad has an area in a range of 0.5 mm? up to 1.5 mm? on.

In one embodiment, each of the second solder pads is in contact with the busbars and not in contact with the fingers.

In one embodiment, the substrate is an N-type semiconductor, the passivation layer is an oxide layer, the oxide layer is disposed on a backside of the substrate, and a

the side of the oxide layer facing away from the substrate is provided with a silver electrode.

In one embodiment, the substrate is a P-type semiconductor, the substrate is provided with an aluminum layer, the aluminum layer is arranged on a side of the passivation layer remote from the substrate, and a side of the substrate remote from the passivation layer is provided with a silver electrode .

[0013] The present disclosure further provides a photovoltaic module. The photovoltaic module includes glass, a first film material, a photovoltaic cell string, a second film material, and a back sheet, which are sequentially arranged from a front side to a back side. The photovoltaic cell string includes a plurality of photovoltaic cells, and each of the plurality of photovoltaic cells is a photovoltaic cell described above.

In one embodiment, the plurality of photovoltaic cells are connected by an electrode line, the electrode line has a circular or near-circular shape, and the electrode line has a diameter in a range of 0.25 mm to 0.4 mm.

In one embodiment, the electrode line has a plurality of flat areas, and a number of the flat areas is greater than or equal to a number of the solder pads.

In one embodiment, the first film material and/or the second film material has a weight in a range from 300 g/m? up to 500 g/m”.

It is to be understood that the foregoing general description and the following detailed description are intended for purposes of illustration only and are not intended to limit the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structural diagram of a photovoltaic cell according to an embodiment of the present disclosure;

FIG. 2 is a schematic structural diagram of a photovoltaic cell according to another embodiment of the present disclosure;

FIG. 3 is a partial enlarged view of position | from FIG. 1; and

4 is a schematic diagram of a partial structure of a photovoltaic cell according to an embodiment of the present disclosure.

DESCRIPTION OF THE EMBODIMENTS

For a better understanding of the technical solutions of the present disclosure, embodiments of the present disclosure will be described below with reference to the accompanying drawings.

It should be understood that the described embodiments represent only some and not all of the embodiments of the present disclosure.

[0024] The terms used in the embodiments of the present disclosure herein are only intended to describe specific embodiments and are not intended to limit the present disclosure. As used in the embodiments of the present disclosure and the appended claims, the singular forms of "a/an," "the," and "named" are intended to include plural forms unless the context clearly indicates otherwise.

It is to be understood that the term "and/or" as used herein is merely an associational relationship describing associated objects, indicating that three relationships can exist. For example, A and/or B indicates that there are three cases: A alone, A and B together, and B alone. In addition, the character "/" here usually means that associated

Objects before and after are in an "or" relationship.

It should be noted that orientation terms such as "top", "bottom", "left" and "right" described in the embodiments of the present disclosure are described from the angles as shown in the accompanying drawings and not are to be understood as limitations of the embodiments of the present disclosure. In addition, in context, it is further understood that when an element is connected "above" or "below" another element, it may not only be directly "above" or "below" another element, but also "indirectly" above" or "below" another element may be connected via an intermediate element.

With the development of technologies, photovoltaic cells have become popular solar devices, and the photovoltaic cells can be broadly classified into N-type photovoltaic cells and P-type photovoltaic cells. When pure silicon is applied to the solar cells and light radiates onto the pure silicon, electrons can break loose from their covalent bonds and leave the atoms, leaving a hole. The electrons are then called free charge carriers, which can carry a current. The pure silicon is mixed with phosphorus atoms. When the phosphorus atoms are used for doping, the resulting silicon is N-type. In one possible embodiment, a substrate of a photovoltaic cell can be an N-type semiconductor. Boron is diffused onto an N-type semiconductor material to form a solar cell with an n/p structure, i. H. an N-type solar cell. A passivation layer on a surface of the substrate is generally an oxide layer. The oxide layer is arranged on a back side of the substrate. A side of the oxide layer facing away from the substrate is provided with a silver electrode. The solar cell can also be of the N type. P-type silicon can be obtained by doping silicon with boron. The P-type silicon has no free electrons. Phosphorus is diffused on a p-type semiconductor material to form a solar cell with p/n-type structure, i. H. a P-type silicon launcher. In one possible embodiment, the substrate of the photovoltaic cell can be a P-type semiconductor. An aluminum layer is arranged on a back surface of the substrate. The aluminum layer is arranged on a side of the passivation layer that faces away from the substrate. A side of the aluminum layer facing away from the passivation layer is also provided with a silver electrode.

As shown in FIG. 1, FIG. 2 and FIG. 3, a photovoltaic cell or solar cell is provided. The photovoltaic cell or solar cell includes a substrate and a passivation layer disposed on a surface of the substrate. The photovoltaic cell converts light energy into electrical energy through a PN junction. The PN-U junction can be made by diffusion to form a diffusion layer. The formation of the passivation layer can increase the light conversion efficiency of the photovoltaic cell. The photovoltaic cell further comprises a busbar 1 and a finger 2, each of which intersects on the surface of the substrate. The busbar 1 is arranged perpendicular to the finger 2 and the busbar 1 is electrically connected to the finger 2 . The finger 2 is electrically connected to the substrate and is adapted to receive a current generated by the substrate. The busbar 1 is designed to receive a current from the finger 2 . The number of busbars 1 is greater than or equal to 11, for example 11, 12, 13 or more. The busbar 1 has a width of 20 μm to 80 μm. For example, the width of busbar 1 may be 20 µm, 30 µm, 40 µm, 50 µm, 60 µm, 70 µm, 80 µm, or the like. The number of fingers 2 is 70 to 160. For example, the number of fingers 2 may be 70, 90, 110, 130, 150, 160 or the like. The finger 2 has a width of 20 µm to 80 µm. For example, the width of finger 2 may be 20 µm, 30 µm, 40 µm, 50 µm, 60 µm, 70 µm, 80 µm or the like. The photovoltaic cell further comprises a soldering pad 3 arranged on the surface of the substrate. The number of soldering pads 3 is 2, 3, 4, 5 or 6. The soldering pad 3 includes first soldering pads 31. The first soldering pads 31 are arranged at two ends of the busbar 1. The first soldering pad 31 has a length and a width between 0.3 mm and 1.2 mm, which can be 0.3 mm, 0.5 mm, 0.7 mm, 0.9 mm, 1.2 mm or the like, for example.

The photovoltaic cell according to embodiments of the present disclosure can be applied to solar cells in a size range of 160+, 180+, 200+ or the like, such as 161.75 mm, 163.75 mm, 166 mm, 182 mm, 188 mm or 210 mm . In general, the 160+ photovoltaic cell can be cut into two half-cells, and the 180+ or 200+ photovoltaic cell can be cut twice into a half slice, or into 3 slices, 4 slices, or other number of slices. For convenience of description, the data according to the embodiments of the present disclosure will be described on the solar cell after cutting.

In comparison to a conventional solar cell comprising 5 or 9 busbars 1, the number of busbars 1 is greater than 11 in the photovoltaic cell according to the present disclosure. By increasing the number of busbars 1, a width of an individual busbar 1 can be reduced , and an area of the individual busbar 1 responsible for current transfer is reduced, thereby reducing the current flowing through the individual busbar 1 . In general, the internal loss of the photovoltaic cell mainly consists of heat generated during operation. According to a formula Q=!”Rt, where Q is the heat generated during operation, i.e. H. the internal main loss, | is the current, R is the resistance and t is the operating time, the busbars 1 are connected in parallel to one another. When the number of busbars 1 is increased, the number of busbars 1 connected in parallel is increased, and the total resistance of the photovoltaic cell decreases. When the current in the circuit decreases and the resistance also decreases, the heat generated by the photovoltaic cell during operation is reduced with a constant operating time, i. H. the internal loss is reduced, which helps improve the overall conversion efficiency of the photovoltaic cell.

The number of soldering pads 3 of a halved photovoltaic cell can be set to 2, 3, 4, 5 or 6. The first soldering pads 31 are arranged at two ends of the busbar 1, and the first soldering pad 31 has a length and a width between 0.3 mm and 1.2 mm, for example 0.3 mm, 0.5 mm, 0.7 mm, 0.9 mm, 1.2 mm or can be the same.

In an embodiment of the present disclosure, the area of the soldering pad 3 is reduced by adjusting the number, the length and the width of the soldering pad 3 such that the shielding of the soldering pad 3 onto the substrate is reduced to avoid the influence of the soldering pad 3 on the light absorption of the substrate and improve the operating efficiency of the photovoltaic cell.

Compared with the conventional photovoltaic cell with 5 busbars, in embodiments of the present disclosure, since the number of busbars 1 is greater than 11, the current consumed by a single busbar 1 is reduced due to the increase in the number of Busbar 1. Therefore, the width of the busbar 1 can be reduced. The solder strength, which is required during soldering, is also correspondingly reduced due to the reduction in the width of the busbar 1. Reducing the area of the first solder pad 31 can reduce the shielding of the first solder pad 31 to the substrate based on maintaining the solder pull force required for the connection, which can also improve the efficiency of the solar cell while reducing the consumption of silver paste and the more in line with actual production and use requirements.

In one possible embodiment, the soldering pad 3 further comprises second soldering pads 32, the second soldering pads 32 are arranged between the first soldering pads 31, and the second soldering pad 32 each has a length and a width of between 0.4 mm and 0.8 mm, for example 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm or the like.

The length and the width of the second soldering pad 32 are set between 0.4mm to 0.8mm, which can reduce the area of the second soldering pad 32 and reduce the shielding of the second soldering pad 32 to the substrate, such that the influence of the second Solder pads 32 is reduced to the light absorption of the substrate and the operating efficiency of the photovoltaic cell is improved.

As shown in FIG. 4, in one possible embodiment, the first solder pad 31 and/or the second solder pad 32 has a shape of a rectangle, a diamond, a circle, an ellipse, or a combination thereof.

The shape of the first soldering pad 31 and/or the second soldering pad 32 is changed such that the shape can be inserted into a conventional square soldering pad to reduce the area of the soldering pad 3, which reduces a shielding area while increasing the connection strength is ensured, the operating efficiency is improved, and at the same time, the consumption of the silver paste and the manufacturing cost are reduced.

In one possible embodiment, the second solder pad 32 has an area of 0.1 mm ® to 0.7 mm ? 0.1 mm®, 0.2 mm?, 0.3 mm?®?, 0.4 mm®, 0.5 mm®, 0.6 mm®, 0.7 mm? or the like. The first soldering pad 31 has an area of 0.5 mm? up to 1.5 mm”? 0.5 mm®, 0.6 mm®, 0.7 mm®, 0.8 mm®, 0.9 mm®, 1.0 mm®?, 1.1 mm®, 1.2 mm®?, 1.3 mm®, 1.4 mm®, 1.5 mm ? or the like.

Compared to the prior art, the areas of the first soldering pad 31 and the second soldering pad 32 are reduced, the shielding area is reduced, the operating efficiency is improved, the silver paste consumption is reduced, and the manufacturing cost is reduced.

In a possible embodiment, the busbar 1 and/or the finger 2 has a dimension of less than or equal to 10 µm along a thickness direction of the photovoltaic cell, which can be, for example, 9 µm, 8 µm or the like, and/or that the first soldering pad 31 and/or the second soldering pad 32 has a dimension less than or equal to 8 µm along the thickness direction of the photovoltaic cell, which may be, for example, 7 µm, 6 µm or the like.

The silver paste consumption is reduced by increasing the number of busbars 1 and reducing the width, such that the thickness of the busbar 1 and/or finger 2 is reduced and the volume of the busbar 1 and/or finger 2 is reduced to reduce a volume of the solder pad 3, which can reduce silver paste materials and reduce manufacturing costs. Due to the reduction in the area of the solder pad 3, the silver paste required in soldering is reduced, which can reduce the shielding of the substrate and reduce the cost. At the same time, by reducing the overall thickness, the thickness of the film material that protects the photovoltaic cell can also be relatively reduced, contributing to cost reduction that better meets the actual usage needs.

In one possible embodiment, the second soldering pad 32 is in contact with the busbar 1 and not with the finger 2.

This design can reduce the possibility of breakage of the busbar at a point of the connection between the busbar 1 and the finger 2 by soldering. As a result, normal use of the photovoltaic cell can be ensured, which is more in line with actual use requirements.

[0044] The present disclosure further provides a photovoltaic module or solar module. The photovoltaic module or solar module comprises glass, a first film material, a photovoltaic cell string, a second film material and a back sheet in sequence from a front side to a back side. The photovoltaic cell string includes a plurality of photovoltaic cells, and each photovoltaic cell is a photovoltaic cell described above.

The glass on the front surface of the photovoltaic cell has a protective and light-transmitting function. The first film material and the second film material are formed to connect and fix the glass, the photovoltaic cell string and the backsheet. The photovoltaic cell string is designed to convert light energy into electrical energy. The backsheet has a sealing, insulating and waterproofing function.

In a possible embodiment, the photovoltaic cells by a

Connected electrode line, the electrode line may have a circular or nearly circular shape and the electrode line has a diameter of 0.25 mm to 0.4 mm. At least part of the electrode line is flattened. That is, the electrode line has a plurality of flat portions. The flat portion is formed to be connected to the soldering pad 3, and the number of the flat portions may be larger than that of the soldering pad 3.

Compared to the previous solution, a thinner electrode line is used, and a shielding area of the solder tab onto the solar cell is reduced, which improves the operation efficiency of the solar cell. A contact area between the flattened electrode line and the photovoltaic cell is increased, which makes it easier for the electrode line to contact the solder pad 3 and can improve the stability and reliability of connection with the electrode line.

In one possible embodiment, the first film material and/or the second film material has a weight of 300 g/m? up to 500 g/m? on. The first film material and the second film material may be made of ethylene vinyl acetate (EVA) or polyethylene terephthalate (PET).

Compared with the existing solution, in embodiments according to the present disclosure, less silver paste is consumed, the electrode line is thinner, the electrode line is less reduced, the electrode line is less likely to pierce the film material, and therefore the first film material and/or the second film material with a lower basis weight, for example EVA or POE, can be selected in order to reduce the production costs.

It should be noted here that the example data in the present disclosure is only preferred and common data within the data range according to an embodiment of the present disclosure, and the rest is not listed. However, according to the present disclosure, data within the data area can achieve the corresponding technical effect.

REFERENCE LIST

1 bus bar; 2 fingers; 3 solder pad;

31 first soldering pad; 32 second solder pad

Claims (10)

Claims are claimed: A photovoltaic cell comprising: a substrate; a passivation layer disposed on at least one surface of the substrate; busbars (1) and fingers (2) each intersecting on the surface of the substrate, the busbars (1) being electrically connected to the fingers (2); and soldering pads (3) arranged on a surface of the substrate, wherein a number of the soldering pads (3) is two to six, the soldering pad (3) includes first soldering pads (31), and the first soldering pads (31) at two ends of one of the busbars (1) are arranged; wherein a number of the busbars (1) is greater than or equal to eleven, and the busbars each have a width of 20 µm to 80 µm, the fingers each have a width of 20 µm to 80 µm, and a number of the fingers seventy to one hundred and sixty amounts to; and the first soldering pads (31) each have a length and a width in a range of 0.3 mm to 1.2 mm. The photovoltaic cell of claim 1, wherein the solder pads (3) further include second solder pads (32), the second solder pads (32) are located between the first solder pads (31), and the second solder pads (32) each have a length and a width in a range from 0.4 mm to 0.8 mm. 3. Photovoltaic cell according to claim 2, wherein the busbars and/or the fingers have a dimension of less than or equal to 10 µm along a thickness direction of the photovoltaic cell, and/or the first soldering pads (31) and/or the second soldering pads (32 ) each have a dimension less than or equal to 8 µm along the thickness direction of the photovoltaic cell. The photovoltaic cell according to claim 2, wherein the first soldering pads (31) and/or the second soldering pads (32) each have a shape of a rectangle, a diamond, a circle, an ellipse or combinations thereof, the first soldering pads (31) respectively an area in a range of 0.5 mm? to 1.5 mm ®, and the second solder pads (32) each have an area in a range from 0.1 mm ® to 0.7 mm? exhibit. 5. A photovoltaic cell according to any one of claims 2 to 4, wherein each of the second solder pads (32) is in contact with the busbars and is not in contact with the fingers. 6. Photovoltaic cell according to one of claims 1 to 4, wherein the substrate is an N-type semiconductor, the passivation layer is an oxide layer, the oxide layer is arranged on a rear side of the substrate and a side facing away from the substrate of the oxide layer is provided with a silver electrode . 7. Photovoltaic cell according to one of claims 1 to 4, wherein the substrate is a P-type semiconductor, the substrate is provided with an aluminum layer, the aluminum layer is arranged on a side facing away from the substrate of the passivation layer and a side facing away from the passivation layer of the Substrate is provided with a silver electrode. 8. A photovoltaic module comprising glass, a first film material, a photovoltaic cell string, a second film material, and a backsheet sequentially arranged from a front side to a backside, the photovoltaic cell string comprising a plurality of photovoltaic cells and each of the plurality of photovoltaic cells is a photovoltaic cell according to any one of claims 1 to 7. 9. The photovoltaic module according to claim 8, wherein the plurality of photovoltaic cells are connected by an electrode line, the electrode line has a circular or nearly circular shape, and the electrode line has a diameter in a range of 0.25 mm to 0.4 mm. 10. Photovoltaic module according to claim 8, wherein the first film material and / or the second film material has a weight in a range of 300 g / m? up to 500 g/m? having. 2 sheets of drawings