CN116885036A - Laser grooving method and device for battery piece, solar battery and photovoltaic module - Google Patents

Abstract

This application relates to a laser grooving method and device for cell sheets, solar cells and photovoltaic components, which includes: forming a plurality of first laser groovings that are parallel to each other and spaced apart along a first direction on the surface of the passivation structure facing away from the substrate. Region; forming a plurality of mutually parallel second laser grooved regions on the surface, so that a first laser grooved region is formed between any two adjacent second laser grooved regions. The first laser grooving area and the second laser grooving area are drawn sequentially, so that the first laser grooving area and the second laser grooving area correspond to the grooving areas of odd grid lines and even grid lines respectively. Thus, the slotted areas corresponding to the odd grid lines and the slotted areas corresponding to the even grid lines of the same cell can be separately adjusted, which can not only reduce the damage caused by the backside slotting to the passivation structure, but also improve the photogenerated load. The ability to transport and collect currents enhances the photoelectric conversion efficiency of the battery.

Description

Laser grooving method and device for cells, solar cells and photovoltaic modules

Technical field

The present application relates to the field of battery technology, and in particular to a laser grooving method and device for battery sheets, solar cells and photovoltaic modules.

Background technique

The emitter and rear passivation cell (Passivated Emitter and Rear Cell, PERC) performs back passivation on the back surface to improve the light reflectivity of the back, and uses laser grooving technology to open the back passivation film layer to form local metal contacts, thereby Export the photogenerated carriers inside the battery. However, as the number of gate lines on the back of the battery increases, when facing the high-density gate technology on the back of PERC cells, the number of laser grooves on the back also increases, resulting in increasing damage to the back passivation film in the grooved area. Large, thereby affecting the backside passivation effect of the battery.

Contents of the invention

Based on this, it is necessary to provide a laser grooving method for battery cells in order to solve the problem that the existing technology cannot effectively reduce the damage to the passivation film layer on the backside due to grooving while facing the high-density grid printing technology on the back of the battery. devices, solar cells and photovoltaic modules.

In order to achieve the above objectives, the present application provides a method for laser grooving of battery sheets. The battery sheets include a substrate and a passivation structure located on the back side of the substrate. The method includes:

A plurality of first laser grooved areas are formed on a surface of the passivation structure away from the substrate, which are parallel to each other and spaced apart along the first direction. Each of the first laser grooved areas includes a plurality of first laser grooved areas along the second direction. First grooved areas arranged at intervals and first spacing areas between each two adjacent first grooved areas;

A plurality of mutually parallel second laser grooved areas are formed on the surface, so that a first laser grooved area is formed between any two adjacent second laser grooved areas, and each of the second laser grooved areas is The second laser grooved area includes a plurality of second grooved areas spaced apart along the second direction and a second spacing area between every two adjacent second grooved areas;

Wherein, the first proportion of any first laser grooved area is different from the second proportion of the second laser grooved area, and the first proportion is a plurality of all laser grooved areas in the second direction. The size of the first grooved area accounts for the proportion of the size of the first laser grooved area, and the second proportion is the size of the plurality of second grooved areas in the second direction accounting for the proportion of the size of the first laser grooved area. A ratio of the dimensions of the second laser grooved area, the first direction being perpendicular to the second direction.

In one embodiment, the grooving starting point of any first laser grooving area is staggered from the grooving starting point of the adjacent second laser grooving area, so that the first grooving area is different from the grooving starting point. The second grooved areas are staggered in the first direction.

In one embodiment, the first grooved area and the second grooved area respectively extend along the second direction, and the method further includes:

Adjust the size of each first grooved area in the same first laser grooved area to change the proportion of the first grooved area to the first laser grooved area;

The size of each second grooved area in the same second laser grooved area is adjusted to change the proportion of the second grooved area to the second laser grooved area.

In one embodiment, the method further includes:

Adjust the size of each first spacer area in the same first laser grooved area to change the proportion of the first grooved area to the first laser grooved area;

The size of each second spacer area in the same second laser grooved area is adjusted to change the proportion of the second grooved area to the second laser grooved area.

In one embodiment, the size proportions of the first grooved areas of at least two of the first laser grooved areas are different; and/or

The size proportions of the second grooved areas of at least two of the second laser grooved areas are different.

In one of the embodiments, it also includes:

Forming a back electrode structure on a plurality of first grooved area surfaces and a plurality of second grooved area surfaces, so that the back electrode structure passes through the first grooved area and the second grooved area An ohmic contact is made with the substrate.

In one embodiment, in the same first laser grooved area, a plurality of the first grooved areas are arranged at equal intervals in sequence along the second direction; and/or

In the same second laser grooved area, a plurality of second grooved areas are arranged at equal intervals in sequence along the second direction.

In one embodiment, one or more laser spots corresponding to patterns are used to form each of the first grooved areas and each of the second grooved areas on the surface.

The present application provides a laser grooving device for battery sheets, which is used to perform the laser grooving method for battery sheets as described above.

The present application provides a solar cell, which is made by using the laser grooving method of the cell sheet as described above.

The present application provides a photovoltaic component, including the solar cell as described above.

The above-mentioned laser grooving method, device, solar cell and photovoltaic module of the cell sheet first form a plurality of first laser grooving areas arranged in parallel and spaced apart on the surface of the passivation structure, and then form a plurality of parallel arranged first laser grooving areas on the surface of the passivation structure. The second laser grooved area is such that each first laser grooved area is interspersed in two adjacent second laser grooved areas, and the first proportion of any first laser grooved area is the same as that of the second laser grooved area. The second proportion of the grooved area is different. The first laser grooved area and the second laser grooved area are drawn sequentially on two layers, so that each first laser grooved area corresponds to the odd grid line and the even grid on the back. One of the lines and each second laser grooved area corresponds to the other of the odd grid line and the even grid line on the back, thereby achieving the slotting area corresponding to the odd grid line and the even grid line of the same cell piece. The slot areas are separately adjusted so that the entire cell sheet can adapt to the requirements of high-density grid slotting. It can not only reduce the damage caused by back slotting to the passivation structure, but also improve the transmission and collection capabilities of photogenerated carriers to enhance the battery's performance. Photoelectric conversion efficiency.

Description of the drawings

In order to more clearly explain the technical solutions in the embodiments of the present application or the traditional technology, the drawings needed to be used in the description of the embodiments or the traditional technology will be briefly introduced below. Obviously, the drawings in the following description are only for the purpose of explaining the embodiments or the technical solutions of the traditional technology. For some embodiments of the application, those of ordinary skill in the art can also obtain other drawings based on these drawings without exerting creative efforts.

Figure 1 is a schematic flowchart of a method for laser grooving of battery cells provided in one embodiment;

FIG. 2 is a partially enlarged structural schematic diagram of the laser grooved structure of the battery sheet provided in one embodiment.

Explanation of reference symbols:

Passivation structure: 100; first laser grooved area: 200; first grooved area: 210; first spacer area: 220; second laser grooved area: 300; second laser grooved area: 310; second spacer District: 320.

Detailed ways

In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are given in the accompanying drawings. However, the present application may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which this application belongs. The terminology used herein in the description of the application is for the purpose of describing specific embodiments only and is not intended to limit the application.

As used herein, the singular forms "a," "an," and "the" may include the plural forms as well, unless the context clearly dictates otherwise. It will also be understood that the terms "comprising" or "having" and the like specify the presence of stated features, integers, steps, operations, components, parts or combinations thereof, but do not exclude the presence or addition of one or more Possibility of other features, integers, steps, operations, components, parts or combinations thereof. Also, in this specification, the term "and/or" includes any and all combinations of the associated listed items.

In one embodiment, a method for laser grooving of a battery sheet is provided. The battery sheet includes a substrate and a passivation structure located on the back side of the substrate.

The cell sheet in this embodiment may be a PERC cell. The substrate of the cell sheet serves as a region that absorbs incident photons and generates photogenerated carriers. It may include one or more of monocrystalline silicon, polycrystalline silicon, and microcrystalline silicon. , and the front side of the substrate is the side surface of the cell sheet that receives light, and the back side of the substrate is the side surface of the cell sheet facing away from the light. It can be understood that in traditional crystalline silicon solar cells, the metal electrode on the back of the cell is in direct contact with the semiconductor substrate, causing severe recombination in the entire contact area between the metal and the semiconductor. Therefore, PERC cells add full-scale contact on the back of the substrate. The covered passivation structure reduces the recombination rate of carriers on the back surface to increase the open circuit voltage of the battery, which not only improves the working efficiency of the battery but also enhances the light reflection effect on the back of the battery.

Optionally, the passivation structure on the back side of the substrate may be a stacked structure, for example, including an aluminum oxide layer and a silicon nitride layer stacked sequentially in a direction away from the substrate, or include a silicon-containing layer, aluminum oxide, silicon oxide, nitride layer, etc. Any one or at least two of silicon and silicon oxynitride. This embodiment does not limit the material and composition of the back passivation structure, but the back passivation structure used needs to be able to provide good surface passivation and reduce metal Contact recombination currents.

Furthermore, laser grooving technology is used to open the passivation structure of the contact area to achieve local metal contact. However, as PERC battery technology becomes more mature, the conversion efficiency of PERC batteries also increases. , High-density gate printing will become a new breakthrough point in PERC battery conversion efficiency. Therefore, as the number of high-density grids on the back increases, the number of laser grooves on the back of the cell also increases. However, the existing laser groove technology has a small adjustment window for the groove pattern and cannot target the groove area of the same cell. The virtual-to-real ratio is adjusted individually. Therefore, when each slotted area is too small, it is easy to cause the photogenerated carrier derivation resistance of the substrate to become larger, and when each slotted area is too large, it will cause excessive damage to the backside passivation structure, and then Affect the passivation effect.

Therefore, based on the current inability to flexibly adjust the groove area ratio when designing the groove area, this embodiment provides a laser groove method for battery cells to solve the above defects, so that when dealing with high-density gate printing technology, not only can the load The effective collection of flow particles can also reduce the passivation damage caused by the increase in the number of back grooves. Please refer to Figure 1 for details. The method includes steps S102 to S104. The laser grooved structure of the battery sheet formed after step S104 is shown in Figure 2.

Step S102: Form a plurality of first laser grooved areas parallel to each other and spaced apart along the first direction on the surface of the passivation structure facing away from the substrate. Each first laser grooved area includes a plurality of first laser grooved areas spaced apart along the second direction. The first grooved area and the first spacing area between each two adjacent first grooved areas.

Wherein, the first direction To form a plurality of first laser grooved areas 200 arranged in parallel and spaced apart along the first direction In a laser grooving area 200, multiple light spots formed by laser ablation technology (also called laser grooving technology) are sequentially tangent or partially overlapped to remove part of the passivation structure 100 to expose part of the substrate, thereby forming a first opening. The groove area 210 is not ablated between the two adjacent first groove areas 210 to form an un-grooved first spacer area 220. Therefore, compared with the first laser groove area 200, it directly penetrates the entire back side of the substrate. The straight-line slotted structure used in this embodiment can greatly reduce the damage area to the back passivation structure 100.

Step S104: Form a plurality of mutually parallel second laser grooved areas on the surface, so that a first laser grooved area is formed between any two adjacent second laser grooved areas. Each second laser grooved area is The area includes a plurality of second grooved areas spaced apart along the second direction and a second spacing area between every two adjacent second grooved areas.

2. Please continue to refer to FIG. 2. The first proportion of any first laser grooved area 200 is different from the second proportion of the second laser grooved area 300. The first proportion is a plurality of first laser grooved areas 200 in the second direction. The size of a grooved area 210 is a proportion of the size of the first laser grooved area 200, and the second ratio is the size of a plurality of second grooved areas 310 in the second direction to the size of the second laser grooved area 300. The first direction is perpendicular to the second direction.

Among them, each row of second laser grooved areas also uses laser ablation technology to remove part of the passivation structure 100 to expose part of the substrate, thereby forming second grooved areas 310 arranged in a line segment, and two adjacent second grooved areas 310 are formed. There is no ablation between the groove areas 310 to form ungrooved second spacer areas 320 .

Further, the first proportion of the first laser grooved area 200 can be understood as the size of the plurality of first grooved areas 210 occupying the first laser grooved area 200 from the left end in the same row of first laser grooved areas 200 The ratio of the distance between the starting point of the groove and the end point of the right end of the groove. The first ratio can also be understood as the size of the first groove area 210 and the size of the first spacer area 220 in the first laser groove area 200 of the same row. The ratio between them is called the first virtual-to-real ratio. In the same way, the second proportion of the second laser grooved area 300 can be understood as the size of the plurality of second grooved areas 310 occupying the second laser grooved area 300 from the left end of the second laser grooved area 300 in the same row. The ratio of the distance between the starting point of the groove and the end point of the right end of the groove. The second proportion can also be understood as the size of the second groove area 310 and the size of the second spacer area 320 in the second laser groove area 300 of the same row. The ratio between them is called the second virtual-to-real ratio. And the above size can be understood as the length of the grooved area along the second direction Y.

It can be understood that, in order to meet the size adjustment requirements for the backside grooved area, after the first laser grooved area 200 is formed, a laser ablation process can be performed on the side surface of the passivation structure 100 facing away from the substrate to form a plurality of The second laser grooved areas 300 are spaced parallelly, and a first laser grooved area 200 is formed between two adjacent second laser grooved areas 300, that is, when multiple second laser grooved areas 300 Compared with when the plurality of first laser grooved areas 200 move upward along the first direction Y by a predetermined distance, the plurality of second laser grooved areas 300 correspond to the odd grid lines on the back of the cell sheet. The groove area 200 corresponds to the grid line on the back of the cell; when the plurality of second laser groove areas 300 move downward by a preset distance in the first direction Y compared to the plurality of first laser groove areas 200, the plurality of second laser groove areas 300 The first laser grooved area 200 corresponds to the odd grid lines on the back of the battery piece, and the plurality of second laser grooved areas 300 corresponds to the even grid lines on the back of the battery piece. Therefore, the laser grooved pattern on the back of the battery piece is divided into third and third laser grooved areas. Two layers of a laser grooved area 200 and a second laser grooved area 300 are drawn sequentially, so that each first laser grooved area 200 corresponds to one of the odd grid lines and the even grid lines on the back, and each second laser The grooved area 300 corresponds to the other one of the odd grid line and the even grid line on the back side, and makes the first proportion of the first laser grooved area 200 different from the second proportion of the second laser grooved area 300 to achieve The slotted areas corresponding to the odd grid lines and the slotted areas corresponding to the even grid lines of the same cell are separately adjusted. That is, by modifying the first virtual-to-real ratio of the first laser grooved area 200 and modifying the second virtual-to-real ratio of the second laser grooved area 300, the grooved areas corresponding to the odd and even gate lines can be separately controlled and adjusted.

For example, FIG. 2 shows a situation in which the plurality of second laser grooved areas 300 move upward by a preset distance in the first direction Y compared to the plurality of first laser grooved areas 200. Therefore, at this time, each second laser grooved area moves upward by a preset distance. The groove area 300 corresponds to the odd grid lines on the back, and each first laser groove area 200 corresponds to the even grid lines on the back. That is, the odd grid lines are printed on each second laser groove area 300, and the even grid lines are printed on each second laser groove area 300. First laser grooved area 200. Furthermore, the size of the second grooved area 310 of the second laser grooved area 300 is smaller than the size of the first grooved area 210 of the first laser grooved area 200, that is, the second proportion of the second laser grooved area 300 is smaller than The first proportion of the first laser grooving area 200, therefore, due to the small size of the second grooving area 310 of the second laser grooving area 300, can reduce the passivation damage caused by backside grooving and reduce the impact on passivation. The negative impact of the passivation effect of the chemical structure 100 is eliminated, and due to the larger size of the first grooved area 210 of the first laser grooved area 200, the transmission and collection ability of photogenerated carriers can be improved, thereby achieving a comprehensive consideration of passivation. The balance between the chemical characteristics and the export of photogenerated carriers can ensure the effective collection of carriers and reduce the passivation damage caused by the increase in the number of back grooves to achieve the best photoelectric conversion efficiency of the cell. .

In the above example, by first forming a plurality of first laser grooved areas arranged in parallel and spaced apart on the surface of the passivation structure, and then forming a plurality of second laser grooved areas arranged in parallel on the surface of the passivation structure, so that each second laser grooved area is A laser grooved area is interspersed between two adjacent second laser grooved areas, and the first proportion of any first laser grooved area is different from the second proportion of the second laser grooved area, so as to Two layers of a first laser grooved area and a second laser grooved area are drawn sequentially, so that each first laser grooved area corresponds to one of the odd grid line and the even grid line on the back, and each second laser grooved area Corresponding to the other of the odd grid lines and the even grid lines on the back, the slotted area corresponding to the odd grid line and the slotted area corresponding to the even grid line of the same cell can be separately adjusted to adapt to high-density grid opening. In addition to reducing the groove requirements, it can not only reduce the damage caused by back grooves to the passivation structure, but also improve the transmission and collection capabilities of photogenerated carriers to enhance the photoelectric conversion efficiency of the battery.

In one embodiment, the laser grooving method of the battery sheet further includes the following steps: forming a back electrode structure on the surfaces of the plurality of first groove areas and the surfaces of the plurality of second groove areas, so that the back electrode structure passes through the first groove area. A grooved area and a second grooved area form ohmic contact with the substrate.

Wherein, the back electrode structure may include an aluminum grid line and a back main grid. It can be understood that after forming a plurality of first laser grooved areas and a plurality of second laser grooved areas through sequential laser ablation, aluminum needs to be printed on the surface of each first grooved area of the first laser grooved area. paste to form odd-numbered aluminum grid lines or even-numbered aluminum grid lines, and aluminum paste is also printed on the surface of each second grooved area of the second laser grooved area to form the other one of odd-numbered aluminum grid lines and even-numbered aluminum grid lines. It should be noted that when aluminum paste is also printed on the surface of the spacer area, the printed aluminum grid lines form a full aluminum back electric field. However, when aluminum paste is not printed on the first spacer area, the printed aluminum grid lines do not fully cover the lining. On the bottom and back, only the grooved areas are printed to form parallel dense aluminum grid lines, which can reduce the consumption of aluminum paste and save costs.

Further, the aluminum paste is filled into each grooved area so that the formed aluminum grid lines form local contact with the substrate, so that the substrate transmits electrons to the aluminum grid lines, and the aluminum grid lines in turn transmit the collected current to the aluminum grid lines. Intersect the back main grid. Therefore, by printing aluminum paste in the first laser grooved area and the second laser grooved area to form a parallel dense aluminum grid structure, the recombination rate of minority carriers can be reduced, and the open circuit voltage and short circuit current of the cell can be increased.

In one embodiment, each first grooved area and each second grooved area are formed on the surface using one or more laser spots corresponding to patterns.

It can be understood that when forming each first grooved area or each second grooved area, the light spots formed by the laser are continuously arranged to carve a grooved area, wherein the shape of the laser light spot can be circular or triangular. , trapezoid, or any one or more combinations of other polygons. The shape of the grooved area formed by the light spot opening can be a groove pattern that is similar to a straight line segment or other shapes.

Furthermore, the size of the grooved area can be adjusted by adjusting the laser parameters, such as pulse frequency and width, or by importing the grooved processing map into the software to achieve grooved area patterns of different shapes and styles, thereby achieving The size of the first grooved area and the size of the second grooved area are modified such that the first proportion of the first laser grooved area is different from the second proportion of the second laser grooved area.

In one embodiment, as shown in FIG. 2 , the grooving starting point of any first laser grooving area 200 is staggered from the grooving starting point of the adjacent second laser grooving area 300 , so that the first grooving area 210 and the second grooved areas 310 are staggered in the first direction.

It can be understood that the grooving starting point (such as the left end starting point) of any first laser grooving area 200 and the grooving starting point of the adjacent second laser grooving area 300 are staggered and misaligned, thus making the first grooving area 210 and the second grooved areas 310 are staggered in the first direction slotted area 310, so the carriers flowing in the first spacer area can be collected by the gate lines filled in the second slotted area 310 above and below it, thereby realizing multi-dimensional collection of photogenerated carriers and shortening the current flow rate The transmission path of carriers from the substrate body to the gate electrode is enhanced to enhance the carrier collection capability, thereby improving the working efficiency of the cell.

In one embodiment, the first grooving area and the second grooving area respectively extend along the second direction. The laser grooving method for the battery sheet further includes the following steps: adjusting each third laser grooving area in the same first laser grooving area. The size of a grooving area to change the proportion of the first grooving area to the first laser grooving area; adjusting the size of each second grooving area in the same second laser grooving area to change the second grooving area Proportion of the second laser grooved area.

For example, each first laser grooved area corresponds to the grooved area of the couple line. By modifying the size of each first grooved area (ie, the length along the second direction) in the same first laser grooved area, it is possible to Changing the first virtual-to-real ratio between the first grooved area and the first spacer area to achieve individual adjustment of the dual gate lines, so that the dual gate line grooved area can reduce damage to the passivation structure or allow the dual gate lines to be grooved The area can improve the collection and transmission capabilities of photogenerated carriers.

Further, when each first laser grooving area corresponds to the grooving area of the even grid line, then each second laser grooving area corresponds to the grooving area of the odd grid line, and further by modifying the same second laser grooving area The size of each second slotted area in the area (that is, the length along the second direction) can change the second virtual-to-real ratio between the second slotted area and the second spacer area, thereby enabling individual adjustment of odd gate lines. . If the size of the first grooving area of the first laser grooving area is small so that the even grid line grooving area can reduce damage to the passivation structure, then the size of the second grooving area of the second laser grooving area is adjusted. Large, so that the odd grid line slotted area can improve the collection and transmission capacity of photogenerated carriers, by sequentially forming the first laser slotted area and the second laser slotted area, and by adjusting the size of the slotted area. The odd and even grid lines of the same cell are separately adjusted to ensure effective collection of carriers while also reducing passivation damage caused by backside slotting.

In one embodiment, the laser grooving method of the battery sheet further includes the following steps: adjusting the size of each first spacer area in the same first laser grooving area to change the proportion of the first grooving area to the first laser grooving area. The proportion of the groove area; adjust the size of each second spacer area in the same second laser groove area to change the proportion of the second groove area to the second laser groove area.

Wherein, for example, each first laser grooved area corresponds to the grooved area of the couple grid line. By modifying the size of each first spacer area in the same first laser grooved area (that is, the spacing between two adjacent first grooved areas) ), the first virtual-to-real ratio between the first slotted area and the first spacer area can be changed, thereby achieving independent adjustment of the dual gate lines, so that the slotted area of the dual gate lines can reduce damage to the passivation structure or make the dual gate lines The line slotted area can improve the collection and transmission capability of photogenerated carriers.

Further, when each first laser grooving area corresponds to the grooving area of the even grid line, then each second laser grooving area corresponds to the grooving area of the odd grid line, and further by modifying the same second laser grooving area The size of each second spacer area in the area (that is, the spacing between two adjacent second grooved areas) can change the second virtual-to-real ratio between the second grooved area and the second spacer area, thereby achieving alignment of odd gate lines. Make individual adjustments. And if the size of the first spacer area in the first laser grooving area is larger, the size of the first grooving area is smaller, so the even gate line grooving area can reduce the damage to the passivation structure, then the second laser The size of the second slotted area in the slotted area is reduced, so that the size of the second slotted area becomes larger, thereby enabling the odd grid line slotted area to improve the collection and transmission capacity of photogenerated carriers to form the first laser in sequence. In the form of a slotted area and a second laser slotted area, and by adjusting the size of the spacer area, the odd and even grid lines of the same cell can be separately adjusted, thereby ensuring effective collection of carriers and reducing the risk of Passivation damage caused by slotting on the back.

In one embodiment, the size proportions of the first grooved areas of at least two first laser grooved areas are different. That is to say, the process of forming the first laser grooved area can be divided into multiple laser ablation operations to partially passivate the structure. Each laser ablation forms a first grooved area spaced apart along the second direction, so it can be adjusted The laser parameters of each time are used to adjust the proportion of the first groove area size of the first laser groove area formed in each row, thereby achieving control and adjustment of each first laser groove area, thereby adapting to more gates. line adjustment requirements.

In one embodiment, the size proportions of the second grooved areas of at least two second laser grooved areas are different. That is to say, the process of forming the second laser grooved area can be divided into multiple laser ablation operations to partially passivate the structure. Each laser ablation forms a second grooved area spaced apart along the second direction, so it can be adjusted The laser parameters of each time are used to adjust the proportion of the second groove area size of the second laser groove area formed in each row, thereby achieving control and adjustment of each second laser groove area, thereby adapting to more gates. line adjustment requirements. Furthermore, in other embodiments, the size proportions of the first grooved areas of the at least two first laser grooved areas are different, and the size proportions of the second grooved areas of the at least two second laser grooved areas are different. are not the same, that is, the size proportion of the first grooved area in each row of the first laser grooved area can be adjusted individually, and the size proportion of the second grooved area in each row of the second laser grooved area can also be adjusted individually, In order to meet the adjustment needs of the grid lines, the problem of damage to the slotted passivation structure on the back of the cell caused by high-density grid printing technology can be solved to a greater extent.

In one embodiment, in the same first laser grooved area, a plurality of first grooved areas are arranged at equal intervals in sequence along the second direction. Wherein, the first laser grooved areas are parallel to each other in the first direction, and the plurality of first grooved areas are arranged at equal intervals in a straight line along the second direction, so that the grid lines formed on each first grooved area are collected The current is more uniform, which is beneficial to improving the current output circuit and optimizing the carrier transmission path.

In one embodiment, in the same second laser grooved area, a plurality of second grooved areas are arranged at equal intervals in sequence along the second direction. Wherein, the second laser grooved areas are parallel to each other in the first direction, and a plurality of second grooved areas are arranged at equal intervals in a straight line along the second direction, so that the grid lines formed on each second grooved area are collected The current is more uniform, which is beneficial to improving the current output circuit and optimizing the carrier transmission path. In other embodiments, in the same first laser grooved area, a plurality of first grooved areas are arranged at equal intervals in sequence along the second direction, and in the same second laser grooved area, a plurality of second grooved areas The zones are arranged at equal intervals in sequence along the second direction.

In one embodiment, a schematic diagram of the laser grooving process of a battery sheet is provided. The size of the battery sheet is 210mm*210mm. First, it is determined that the spacing between two adjacent rows of grid lines on the back is 1.12mm. A plurality of first laser grooved areas are formed in the center on the surface of the chemical structure away from the substrate, and then a plurality of second laser grooved areas are formed in the center at a position where the entire first laser grooved area is moved upward by 1.12 mm along the first direction X. groove area, so that the distance between two adjacent second laser groove areas is 2.24mm, and then the first groove area of each first laser groove area is filled with aluminum paste, and each second laser groove area is filled with aluminum paste. The second grooved area of the grooved area is filled with aluminum slurry, so that the first laser grooved area and the second laser grooved area drawn in sequence can respectively correspond to the odd and even lines of the grid lines, modifying the laser grooved areas in different laser grooved areas. The virtual-to-real ratio and other laser parameters achieve separate control and adjustment of odd and even grid lines.

In one embodiment, a solar cell is provided, which is manufactured by using the laser grooving method of the cell sheet as described in the above embodiment. After the above-mentioned solar cells have been optimized through the laser grooving method of the cell, the passivation loss caused by the grooving on the back of the cell is reduced, allowing the solar cell to enhance its carrier collection ability, thereby improving the electrical performance and performance of the solar cell. Yield rate.

In one embodiment, based on the same inventive concept, a laser grooving device for battery sheets is provided, which is used to perform the laser grooving method for battery sheets as described in the above embodiment.

In one embodiment, a photovoltaic component is provided, including the solar cell as described in the above embodiment.

Among them, the photovoltaic module includes a battery string, and the battery string is composed of multiple solar cells connected. The photovoltaic module also includes an encapsulation layer and a cover plate. The encapsulation layer is used to cover the surface of the battery string, and the cover plate is used to cover the encapsulation layer away from the battery string. surface. The solar cells are electrically connected in the form of a whole piece or multiple slices to form multiple battery strings, and the multiple battery strings are electrically connected in series and/or in parallel. Specifically, in some embodiments, multiple battery strings may be electrically connected through conductive charges. The encapsulation layer covers the surface of the solar cell. For example, the encapsulating layer may be an organic encapsulating adhesive film such as an ethylene-vinyl acetate copolymer adhesive film, a polyethylene octene co-elastomer adhesive film, or a polyethylene terephthalate adhesive film. The cover plate can be a glass cover plate, a plastic cover plate, or other cover plate with a light-transmitting function.

It should be understood that although various steps in the flowchart of FIG. 1 are shown in sequence as indicated by arrows, these steps are not necessarily executed in the order indicated by arrows. Unless explicitly stated in this article, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least some of the steps in Figure 1 may include multiple steps or stages. These steps or stages are not necessarily executed at the same time, but may be executed at different times. The execution order of these steps or stages is also It does not necessarily need to be performed sequentially, but may be performed in turn or alternately with other steps or at least part of steps or stages in other steps.

In the description of this specification, reference to the terms "some embodiments," "other embodiments," "ideal embodiments," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included herein. In at least one embodiment or example of the application. In this specification, schematic descriptions of the above terms do not necessarily refer to the same embodiment or example.

The technical features of the above embodiments can be combined in any way. To simplify the description, not all possible combinations of the technical features of the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, all possible combinations should be used. It is considered to be within the scope of this manual.

The above-described embodiments only express several implementation modes of the present application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent application. It should be noted that, for those of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all fall within the protection scope of the present application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims (11)

1. A method for laser grooving of battery sheets, characterized in that the battery sheet includes a substrate and a passivation structure located on the back side of the substrate, and the method includes: A plurality of first laser grooved areas are formed on a surface of the passivation structure away from the substrate, which are parallel to each other and spaced apart along the first direction. Each of the first laser grooved areas includes a plurality of first laser grooved areas along the second direction. First grooved areas arranged at intervals and first spacing areas between each two adjacent first grooved areas; A plurality of mutually parallel second laser grooved areas are formed on the surface, so that a first laser grooved area is formed between any two adjacent second laser grooved areas, and each of the second laser grooved areas is The second laser grooved area includes a plurality of second grooved areas spaced apart along the second direction and a second spacing area between every two adjacent second grooved areas; Wherein, the first proportion of any first laser grooved area is different from the second proportion of the second laser grooved area, and the first proportion is a plurality of all laser grooved areas in the second direction. The size of the first grooved area accounts for the proportion of the size of the first laser grooved area, and the second proportion is the size of the plurality of second grooved areas in the second direction accounting for the proportion of the size of the first laser grooved area. A ratio of the dimensions of the second laser grooved area, the first direction being perpendicular to the second direction. 2. The laser grooving method for battery cells according to claim 1, characterized in that the grooving starting point of any first laser grooving area is the same as the grooving starting point of the adjacent second laser grooving area. The starting points are staggered so that the first grooved areas and the second grooved areas are staggered in the first direction. 3. The laser grooving method for battery cells according to claim 1, wherein the first grooving area and the second grooving area respectively extend along the second direction, and the method further includes : Adjust the size of each first grooved area in the same first laser grooved area to change the proportion of the first grooved area to the first laser grooved area; The size of each second grooved area in the same second laser grooved area is adjusted to change the proportion of the second grooved area to the second laser grooved area. 4. The laser grooving method for battery sheets according to claim 1, characterized in that the method further includes: Adjust the size of each first spacer area in the same first laser grooved area to change the proportion of the first grooved area to the first laser grooved area; The size of each second spacer area in the same second laser grooved area is adjusted to change the proportion of the second grooved area to the second laser grooved area. 5. The laser grooving method for battery cells according to any one of claims 3 to 4, characterized in that the size ratios of the first grooving areas of at least two first laser grooving areas are different; and / or The size proportions of the second grooved areas of at least two of the second laser grooved areas are different. 6. The laser grooving method for battery sheets according to any one of claims 1 to 4, characterized in that it further includes: Forming a back electrode structure on a plurality of first grooved area surfaces and a plurality of second grooved area surfaces, so that the back electrode structure passes through the first grooved area and the second grooved area An ohmic contact is made with the substrate. 7. The laser grooving method for battery cells according to any one of claims 1 to 4, characterized in that, in the same first laser grooving area, a plurality of the first grooving areas are located along the Arranged at equal intervals in the second direction; and/or In the same second laser grooved area, a plurality of second grooved areas are arranged at equal intervals in sequence along the second direction. 8. The laser grooving method for battery cells according to claim 1, characterized in that each of the first grooving areas and each of the first grooving areas and each of the first grooving areas are formed on the surface using laser spots corresponding to one or more patterns. Describe the second grooved area. 9. A laser grooving device for battery sheets, characterized in that the device is used to perform the laser grooving method for battery sheets according to any one of claims 1 to 8. 10. A solar cell, characterized in that it is made by using the laser grooving method of the cell sheet according to any one of claims 1 to 8. 11. A photovoltaic module, characterized by comprising the solar cell according to claim 10.