Solar cell

Abstract

The utility model discloses a solar cell which comprises a plurality of cell units, and each cell unit comprises a first electrode layer, a functional layer and a second electrode layer which are stacked in sequence. The solar cell is provided with a plurality of first notch grooves, a plurality of second notch grooves and a plurality of third notch grooves along a first direction; the first notch groove penetrates through the first electrode layer; the first notch groove comprises a plurality of first notch groove subunits which are arranged at intervals in the second direction and are sequentially connected, each first notch groove subunit at least comprises a semi-closed structure, and the vertical projection of each semi-closed structure is triangular; the second notch groove penetrates through the functional layer and is filled with the second electrode layer; the second notch groove comprises a plurality of second notch groove subunits which are arranged at intervals along the second direction; each semi-closed structure at least partially surrounds the corresponding second grooving subunit; and the third notch groove penetrates through the second electrode layer and the functional layer, so that the dead zone area of the solar cell is reduced, and the problem of low photoelectric conversion efficiency of the solar cell is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a solar cell. Background Art

[0002] In recent years, new solar cells represented by perovskite and organic thin-film solar cells have developed rapidly due to their advantages of high efficiency, low cost and simple process.

[0003] However, the path portion of the battery cells connected in series in the solar cell does not contribute to the photocurrent, resulting in a decrease in the photoelectric conversion efficiency of the solar cell. Utility Model Content

[0004] The utility model provides a solar cell to reduce the dead zone area of ​​the solar cell, thereby solving the problem of low photoelectric conversion efficiency of the solar cell.

[0005] According to one aspect of the present invention, a solar cell is provided, comprising a plurality of battery cells, wherein the battery cells comprise a first electrode layer, a functional layer, and a second electrode layer stacked in sequence;

[0006] The solar cell is provided with a plurality of first grooves, a plurality of second grooves and a plurality of third grooves along a first direction, and the solar cell is divided into a plurality of battery cells connected in series in sequence by the plurality of first grooves, the plurality of second grooves and the plurality of third grooves;

[0007] The first groove passes through the first electrode layer, and the functional layer is filled in the first groove; the first groove includes a plurality of first groove sub-units spaced apart and sequentially connected along a second direction, the first groove sub-units at least including a semi-enclosed structure, and a vertical projection of the semi-enclosed structure is a triangle; wherein the second direction intersects the first direction;

[0008] The second groove penetrates the functional layer and is filled with the second electrode layer, so that the first electrode layer and the second electrode layer are in contact with each other; the second groove includes a plurality of second groove sub-units spaced apart along the second direction, the second groove sub-units corresponding to the semi-enclosed structures; each of the semi-enclosed structures at least partially surrounds a corresponding second groove sub-unit;

[0009] The third groove penetrates the second electrode layer and the functional layer.

[0010] Optionally, each of the first grooves only includes the semi-enclosed structure, and the multiple semi-enclosed structures included in the first groove are connected in sequence.

[0011] Optionally, each of the first grooved sub-units further includes a connecting portion, and the semi-enclosed structures in two adjacent first grooved sub-units are connected via the connecting portion of the preceding first grooved sub-unit in the two adjacent first grooved sub-units.

[0012] Optionally, the length of the connecting portion along the second direction is between 0 μm and 10000 μm.

[0013] Optionally, the lengths of the connecting portions along the second direction are equal, and the lengths of the openings surrounded by the semi-enclosed structures along the second direction are equal.

[0014] Optionally, the semi-enclosed structure includes a first oblique side and a second oblique side connected in sequence, and an angle between the first oblique side and the second oblique side is greater than or equal to ninety degrees.

[0015] Optionally, a vertical projection of the second groove subunit overlaps with a vertical projection of the corresponding opening enclosed by the semi-enclosed structure.

[0016] Optionally, the length of the opening surrounded by the semi-enclosed structure along the second direction is between 85 μm and 1000 μm.

[0017] Optionally, the semi-enclosed structure includes a first oblique side and a second oblique side connected in sequence, and the lengths of the first oblique side and the second oblique side are both between 60 μm and 600 μm.

[0018] Optionally, a maximum distance between the first groove and the third groove in the first direction is between 90 μm and 900 μm.

[0019] The technical solution of the embodiment of the utility model is that the first groove includes multiple first groove sub-units connected in sequence, and each first groove sub-unit further includes a semi-enclosed structure. The semi-enclosed structure forms an opening, the second groove sub-unit is located within the corresponding opening, and the third groove is arranged toward the opening of the semi-enclosed structure, thereby reducing the distance between the first and third grooves, effectively reducing the dead zone area between the first and third grooves. Moreover, the vertical projection of the semi-enclosed structure is a triangle. When the distance between the first and third grooves is constant, the triangle occupies the smallest area compared to other shapes, further reducing the dead zone area, increasing the power generation area, and improving the photoelectric conversion efficiency of the solar cell.

[0020] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0022] Figure 1 A cross-sectional view of a solar cell provided by an embodiment of the present utility model;

[0023] Figure 2 A schematic structural diagram of a first groove, a second groove, and a third groove provided in an embodiment of the present utility model;

[0024] Figure 3 A comparison diagram of different shapes of a semi-enclosed structure provided by an embodiment of the utility model;

[0025] Figure 4 A schematic structural diagram of another first groove, second groove and third groove provided in an embodiment of the present utility model. DETAILED DESCRIPTION

[0026] In order to help those skilled in the art better understand the present invention, the following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0027] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0028] Figure 1 A cross-sectional view of a solar cell provided in an embodiment of the present utility model, Figure 2A schematic structural diagram of a first groove, a second groove and a third groove provided in an embodiment of the present invention, with reference to Figure 1 and Figure 2 Optionally, the solar cell includes a plurality of battery cells 8, each battery cell 8 including a first electrode layer 1, a functional layer 2, and a second electrode layer 3 stacked in sequence;

[0029] The solar cell is provided with a plurality of first grooves 5, a plurality of second grooves 6 and a plurality of third grooves 7 along a first direction X. The solar cell is divided into a plurality of battery cells 8 connected in series in sequence by the plurality of first grooves 5, the plurality of second grooves 6 and the plurality of third grooves 7.

[0030] The first groove 5 penetrates the first electrode layer 1 and is filled with the functional layer 2. The first groove 5 includes a plurality of first groove subunits spaced apart and sequentially connected along the second direction Y. The first groove subunits include at least a semi-enclosed structure 51. The vertical projection of the semi-enclosed structure 51 is a triangle. The second direction Y intersects the first direction X.

[0031] The second groove 6 penetrates the functional layer 2 and is filled with the second electrode layer 3, so that the first electrode layer 1 and the second electrode layer 3 are in contact with each other. The second groove 6 includes a plurality of second groove sub-units 61 spaced apart along the second direction Y. The second groove sub-units 61 correspond to the semi-enclosed structures 51, specifically, one-to-one. Each semi-enclosed structure 51 at least partially surrounds the corresponding second groove sub-unit 61.

[0032] The third groove 7 penetrates the second electrode layer 3 and the functional layer 2 .

[0033] Optionally, the solar cell further includes a substrate 4, each battery cell 8 is formed on the same side of the substrate 4, and the first electrode layer 1 is arranged between the substrate 4 and the functional layer 2. The material of the substrate 4 can be glass, quartz, silicon or the like. The material of the first electrode layer 1 and the second electrode layer 3 can both be indium tin oxide (ITO). The functional layer 2 includes a hole transport layer 21, a perovskite layer 22 and an electron transport layer 23 stacked in sequence from the side of the first electrode layer 1 close to the second electrode layer 3, or the functional layer 2 includes an electron transport layer 23, a perovskite layer 22 and a hole transport layer 21 stacked in sequence from the side of the first electrode layer 1 close to the second electrode layer 3, Figure 1As shown in the figure, the hole transport layer 21 is located between the first electrode layer 1 and the perovskite layer 22. Optionally, the perovskite layer 22 includes, but is not limited to, MAPbI3, FAPbI3, FAMAPbI3, FACsPbI3, FAMACsPbI3, etc. The electron transport layer 23 includes, but is not limited to, one or a combination of PCBM, TiO2, SnO2, ZnO, Nb2O5, etc. The hole transport layer 21 includes, but is not limited to, one or a combination of NiO, Spiro-OMeTAD, CuGaO2, CuSCN, P3HT, PEDOT:PSS, etc. The vertical projections in this embodiment are all orthographic projections on the substrate 4.

[0034] The first groove 5 is a scribe line that runs through the first electrode layer 1 along the stacking direction Z. The stacking direction Z is the stacking direction of the first electrode layer 1, the functional layer 2, and the second electrode layer 3. Any two of the first direction X, the second direction Y, and the stacking direction Z are perpendicular to each other. The first direction X can be either the length or width direction of the solar cell, and the second direction Y can be the other of the length or width direction of the solar cell. The second groove 6 is a scribe line that runs through the electron transport layer 23, the perovskite layer 22, and the hole transport layer 21 along the stacking direction Z. The third groove 7 is a scribe line that runs through the second electrode layer 3, the electron transport layer 23, the perovskite layer 22, and the hole transport layer 21 along the stacking direction Z. There are multiple first grooves 5, second grooves 6, and third grooves 7, and the multiple first grooves 5, second grooves 6, and third grooves 7 are spaced apart along the first direction X, dividing the solar cell into multiple cells 8 along the first direction X.

[0035] The method for making the first groove 5 includes but is not limited to one of chemical etching, mechanical etching, and laser etching. In this embodiment, a 355nm ultraviolet light source is used for processing. The light output mode can be selected from the upper light output or the lower light output. In this embodiment, the upper light output is selected. The processing motion mode can adopt the motion mode of galvanometer stepping, platform (glass) flying, or galvanometer flying motion, platform (glass) stepping. In this embodiment, the motion mode of galvanometer stepping and platform (glass) flying is adopted to realize the etching shape specified by the first groove 5. When etching the first groove 5, the engraved pattern includes a semi-closed triangle. The pattern is formed by splicing high-frequency pulse point-shaped light spots. The visual camera assists in identifying the outer contour of the glass and locating the specific position coordinates of the semi-closed structure 51. The galvanometer accurately laser engraves the pattern of the first groove 5 through high-speed deflection. The processing speed is 1000mm / s-20000mm / s, the frequency is 10khz-4000khz, the power is 1.5w-3w, and the focus is positive. The pulse laser spot size of each first groove 5 is between 10 μm and 100 μm. The first groove 5 is filled with the hole transport layer 21 .

[0036] The manufacturing method of the second groove 6 includes but is not limited to one of mechanical engraving and laser etching. In this embodiment, the laser etching solution is selected; the selection of the laser light source includes but is not limited to one of green light 532nm, ultraviolet 355nm, etc. In this embodiment, a green light 532nm light source is used for processing; the light output mode can be selected by upper light output or lower light output, and in this case, the upper light output is used; the processing motion mode can be selected by galvanometer stepping, platform (glass) flying motion mode or galvanometer flying motion, platform (glass) stepping motion mode. In this embodiment, the galvanometer stepping, platform (glass) flying motion mode is used to achieve the etching shape specified by the second groove 6. The second groove 6 includes the second groove 6. The vertical projection of the groove subunit 61 onto the substrate 4 includes, but is not limited to, a triangle, a circle, a rectangle, or a bar, filling the semi-enclosed area formed by the semi-enclosed structure 51 in the first groove 5. The pattern is formed by splicing high-frequency pulsed point light spots or irregular light spots after optical path shaping. A visual camera assists in identifying and locating the shape and position of the first groove 5. The galvanometer accurately laser engraves the pattern of the second groove 6 through high-speed deflection, assisting visual recognition and positioning, and then accurately filling the gap in the semi-enclosed structure 51. The pattern can be edited and filled in advance. The processing speed is 1500mm / s-20000mm / s, the frequency is 10Hz-4000kHz, the power is 0.5-2W, and the focus is positive. The second groove subunit 61 in the second groove 6 is filled with the second electrode layer 3 to connect the second electrode layer 3 of the adjacent previous battery cell 8 with the first electrode layer 1 of the subsequent battery cell 8, thereby interconnecting the adjacent battery cells 8.

[0037] The method for making the third groove 7 adopts one of the following methods including but not limited to mechanical scratching, laser etching, etc., and the present embodiment selects the laser etching scheme, and the selection of the laser light source includes but is not limited to one of infrared 1064nm, green light 532nm, ultraviolet 355nm, etc., and the present embodiment adopts the ultraviolet 355nm light source for processing; the selection of the light output mode can adopt the upper light output or the lower light output, and the present embodiment adopts the upper light output; the selection of the processing motion mode can adopt the platform (glass) flying motion, the light path stepping mode or the light path flying motion, the platform (glass) stepping mode to realize the scratching of the third groove 7, and the present embodiment adopts the light path stepping, the platform (glass) flying motion mode for processing; the selection of the focusing structure can adopt the focusing mirror or the galvanometer mode to realize the scratching of the third groove 7, and the present embodiment adopts the focusing mirror structure to realize the processing of the third groove 7; wherein, the processing speed is 800mm / s-1300mm / s, the frequency is 400khz-2000khz, and the power is 0.2w-1w. Visual recognition of the shape and position of the first groove 5 is used to confirm the specific position coordinates of the third groove 7. The entire third groove 7 is arranged parallel to the first groove 5. The vertical projection of the third groove 7 on the substrate is a straight line. It is formed by connecting high-frequency pulsed laser spots, with a single spot diameter ranging from 10-100μm. The third groove 7 separates the second electrode layer 3 of adjacent battery cells 8, forming a complete battery cell 8. The first groove 5, second groove 6, and third groove 7 are all formed by connecting high-frequency pulsed laser spots, and the line width of each groove can be effectively controlled within 100μm.

[0038] The first groove 5 includes multiple first groove subunits, each of which includes a semi-enclosed structure 51. The semi-enclosed structures 51 correspond one-to-one with second groove subunits 61. The second groove subunits 61 are disposed within the semi-enclosed area, or opening, formed by the corresponding semi-enclosed structure 51. The semi-enclosed structure 51 has an opening, and the third groove 7 is disposed toward the opening of the semi-enclosed structure 51. The vertical projection of the semi-enclosed structure 51 is triangular. When the distance between the first groove 5 and the third groove 7 along the first direction X is fixed, the area occupied by the triangle is minimized, thereby facilitating the reduction of the dead zone A1, the increase of the effective zone A2, and the improvement of photoelectric conversion efficiency. Furthermore, the triangle has fewer inflection points, which facilitates actual production and processing, improving pattern precision. No photocurrent is generated within the dead zone A1, while photocurrent can be generated within the effective zone A2.

[0039] Figure 3 A comparison diagram of different shapes of a semi-enclosed structure provided by an embodiment of the utility model, Figure 3, a comparison is shown when the semi-enclosed structure is an arc and a triangle. Taking an opening size of 20,000 μm*10,000 μm, a spacing of 1,500 μm between the first notch 5 and the third notch 7, and an overall size of a solar cell of 2,000 mm*1,000 mm as an example, referring to Table 1, it can be seen that when the semi-enclosed structure is a triangle, the dead zone area ratio is smaller than the dead zone area when the first notch is a straight line, the semi-enclosed structure is a rectangle, or the semi-enclosed structure is an arc, which is beneficial to increasing the area ratio of the effective area A2 and improving the photoelectric conversion efficiency.

[0040] Table 2. Comparison of dead zone area ratios of different patterns of semi-enclosed structures

[0041]

[0042] The technical solution of the embodiment of the utility model is that the first groove includes multiple first groove sub-units connected in sequence, and each first groove sub-unit further includes a semi-enclosed structure. The semi-enclosed structure forms an opening, the second groove sub-unit is located within the corresponding opening, and the third groove is arranged toward the opening of the semi-enclosed structure, thereby reducing the distance between the first and third grooves, effectively reducing the dead zone area between the first and third grooves. Moreover, the vertical projection of the semi-enclosed structure is a triangle. When the distance between the first and third grooves is constant, the triangle occupies the smallest area compared to other shapes, further reducing the dead zone area, increasing the area of ​​the effective area, and improving the photoelectric conversion efficiency of the solar cell.

[0043] Continue to refer Figure 1 and Figure 2 Optionally, each first groove 5 only includes a semi-enclosed structure 51, and the multiple semi-enclosed structures 51 included in the first groove 5 are connected in sequence to achieve the sequential connection of multiple first groove sub-units.

[0044] Because the number of second grooved sub-units 61 is the same as the number of semi-enclosed structures 51, the multiple semi-enclosed structures 51 in the first groove 5 are continuously connected, which can make the number of second grooved sub-units 61 larger, thereby increasing the contact points and contact area between the second electrode layer 3 and the first electrode layer 1, which is beneficial to ensuring the stability of the series connection between multiple battery cells 8.

[0045] Optionally, the semi-enclosed structure 51 includes a first bevel 511 and a second bevel 512. For any first groove 5, the lengths of the first bevel 511 and the second bevel 512 of each semi-enclosed structure 51 are equal, and the lengths of the second bevel 512 are equal, ensuring that the sizes of each semi-enclosed structure 51 are the same.

[0046] Alternatively, the first groove subunit is a discontinuous structure, Figure 4 Another structural diagram of the first groove, the second groove and the third groove provided in the embodiment of the utility model is shown in FIG. Figure 1 and Figure 4 Optionally, each first grooved subunit further includes a connecting portion 52, and the semi-enclosed structures 51 in two adjacent first grooved subunits are connected via the connecting portion 52 of the previous first grooved subunit in the two adjacent first grooved subunits; or, except for the last first grooved subunit in the plurality of sequentially connected first grooved subunits, each remaining first grooved subunit further includes a connecting portion 52, and the semi-enclosed structures 51 in two adjacent first grooved subunits are connected via the connecting portion 52 of the previous first grooved subunit in the two adjacent first grooved subunits. Optionally, the vertical projection of the connecting portion 52 is a straight line.

[0047] Illustratively, the semi-enclosed structure 51 of the first first grooved subunit and the semi-enclosed structure 51 of the second first grooved subunit are connected through the connecting portion 52 of the first first grooved subunit, the semi-enclosed structure 51 of the second first grooved subunit and the semi-enclosed structure 51 of the third first grooved subunit are connected through the connecting portion 52 of the second first grooved subunit, and so on.

[0048] The semi-enclosed structures 51 are discontinuous structures connected by connecting parts 52. When the area of ​​the solar cell is fixed, the total occupied area of ​​all semi-enclosed structures 51 can be reduced, thereby reducing the proportion of the total area of ​​the dead zone A1 and improving the photoelectric conversion efficiency.

[0049] Continue to refer Figure 1 and Figure 4 Optionally, the lengths of the connecting portions 52 along the second direction Y are equal, and the lengths of the openings enclosed by the semi-enclosed structures 51 along the second direction Y are equal. That is, for any first notch 5, the sizes of the semi-enclosed structures 51 in each first notch subunit, as well as the spacing between two adjacent semi-enclosed structures 51, are the same. This allows for a uniform arrangement of the first notch subunits, facilitating process production. Furthermore, the multiple first notches 5, multiple second notches 6, and multiple third notches 7 are uniformly arranged along the first direction X, facilitating the formation of battery cells 8 of uniform specifications.

[0050] Continue to refer Figure 1 and Figure 4 Optionally, the length of the connecting portion 52 along the second direction Y is between 0 μm and 10000 μm.

[0051] The length of the solar cell substrate 4 along the second direction Y is 2000 mm, and the length of the connecting portion 52 along the second direction Y is between 0 μm and 10,000 μm. If the length of the connecting portion 52 along the second direction Y is too long, there will be too few contact points between the first electrode layer 1 and the second electrode layer 3, reducing the conductivity and easily leading to poor contact between the individual battery cells 8. Therefore, the length of the connecting portion 52 should be set within a reasonable range to ensure a reasonable number of contact points between the first electrode layer 1 and the second electrode layer 3, ensuring good contact between the individual electrode cells 8 and improving the conductivity of the solar cell.

[0052] refer to Figure 1 and Figure 2 , or refer to Figure 1 and Figure 4 Optionally, the semi-enclosed structure 51 includes a first oblique side 511 and a second oblique side 512 connected in sequence, and the angle between the first oblique side 511 and the second oblique side 512 is greater than or equal to ninety degrees.

[0053] The semi-enclosed structure 51 is a triangle, and the angle of the triangle vertex is greater than or equal to 90 degrees. Therefore, the area of ​​the opening enclosed by each semi-enclosed structure 51 is larger, so that the area of ​​the region where the second groove sub-unit 61 can be set is larger, and thus a larger process tolerance can be reserved when the second groove sub-unit 61 is processed, thereby reducing the impact of the position deviation of the second groove sub-unit 61 caused by process errors on the photoelectric conversion efficiency of the solar cell.

[0054] refer to Figure 1 and Figure 4 Optionally, the vertical projection of the second groove sub-unit 61 overlaps with the vertical projection of the opening surrounded by the corresponding semi-enclosed structure 51.

[0055] The vertical projection of the second grooved subunit 61 is also triangular in shape. The second grooved subunit 61 includes a third hypotenuse and a fourth hypotenuse. The third hypotenuse is parallel to the first hypotenuse 511 of the corresponding semi-enclosed structure 51, and the fourth hypotenuse is parallel to the second hypotenuse 512 of the corresponding semi-enclosed structure 51. The angle between the third and fourth hypotenuses is equal to the angle between the first and second hypotenuses of the corresponding semi-enclosed structure 51. The vertical projection of the second grooved subunit 61 overlaps with the vertical projection of the opening enclosed by the corresponding semi-enclosed structure 51, allowing the second electrode layer 3 filled in the second grooved subunit 61 to completely fill the opening enclosed by the corresponding semi-enclosed structure 51. This increases the contact area between the first electrode layer 1 and the second electrode layer 3, improves electrical conductivity, reduces the connection resistance between the individual battery cells 8, and further improves photoelectric conversion efficiency.

[0056] refer to Figure 1 and Figure 2 , or, refer to Figure 1 and Figure 4 Optionally, the length of the opening enclosed by the semi-enclosed structure 51 along the second direction Y is between 85μm and 1000μm. When the spacing between the first groove 5 and the third groove 7 is fixed, if the length of the opening enclosed by the semi-enclosed structure 51 along the second direction Y is small, the number of semi-enclosed structures 51 is large, resulting in more inflection points that need to be formed during etching, which is not conducive to process processing. If the length of the opening enclosed by the semi-enclosed structure 51 along the second direction Y is large, the number of contact points between the first electrode layer 1 and the second electrode layer 3 is small, which is not conducive to connection stability. Therefore, the length of the opening enclosed by the semi-enclosed structure 51 along the second direction Y needs to be set within a reasonable range.

[0057] refer to Figure 1 and Figure 2 , or, refer to Figure 1 and Figure 4 Optionally, the semi-enclosed structure 51 includes a first oblique side 511 and a second oblique side 512 connected in sequence, and the lengths of the first oblique side 511 and the second oblique side 512 are both between 60μm and 600μm. The lengths of the first oblique side 511 and the second oblique side 512 can be equal. If the lengths of the first oblique side 511 and the second oblique side are small, the area of ​​the opening enclosed by each semi-enclosed structure 51 is small, resulting in a small area of ​​the area where the second groove sub-unit 61 can be set, which is prone to position deviation when etching the second groove sub-unit 61 due to process errors. If the lengths of the first oblique side 511 and the second oblique side are large, the number of semi-enclosed structures 51 is small, and the number of contact points between the first electrode layer 1 and the second electrode layer 3 is also small, which is not conducive to the stability of the connection between the battery cells 8. Therefore, the lengths of the first oblique side 511 and the second oblique side 512 need to be set within a reasonable range, taking into account the allowable process error when etching the second groove sub-unit 61 and the stability of the connection between the battery cells 8.

[0058] Continue to refer Figure 1 and Figure 2 , or, refer to Figure 1 and Figure 4 Optionally, the maximum distance between the first groove 5 and the third groove 7 in the first direction X is between 90 μm and 900 μm. That is, the vertical distance from the vertex of the semi-enclosed structure 51 to the third groove 7 is between 90 μm and 900 μm.

[0059] If the spacing between the first and third grooves 5, 7 is too large, the dead zone area will be large, which is not conducive to improving the photoelectric conversion efficiency. If the spacing between the first and third grooves 5, 7 is too small, the etching position errors may occur when etching each groove using existing technology due to process deviations. Therefore, it is necessary to balance the photoelectric conversion efficiency and etching errors to set the spacing between the first and third grooves 5, 7 in the first direction X within a reasonable range.

[0060] In this embodiment, the triangular shape of the semi-enclosed structure in the first notch can reduce the dead zone area of ​​the solar cell, increase the effective power generation area of ​​the solar cell, and improve the overall power generation of the cell. Furthermore, by changing the pattern of the first notch, processing stability and reliability are significantly improved.

[0061] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this utility model can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of this utility model can be achieved. This is not limited herein.

[0062] The above specific embodiments do not limit the scope of protection of this utility model. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model shall be included within the scope of protection of this utility model.

Claims

1. A solar cell, characterized in that: The battery cell comprises a plurality of battery cells, each of which comprises a first electrode layer, a functional layer, and a second electrode layer stacked in sequence; The solar cell is provided with a plurality of first grooves, a plurality of second grooves and a plurality of third grooves along a first direction, and the solar cell is divided into a plurality of battery cells connected in series in sequence by the plurality of first grooves, the plurality of second grooves and the plurality of third grooves; The first groove passes through the first electrode layer, and the functional layer is filled in the first groove; the first groove includes a plurality of first groove sub-units spaced apart and sequentially connected along a second direction, the first groove sub-units at least including a semi-enclosed structure, and a vertical projection of the semi-enclosed structure is a triangle; wherein the second direction intersects the first direction; The second groove penetrates the functional layer and is filled with the second electrode layer, so that the first electrode layer and the second electrode layer are in contact with each other; the second groove includes a plurality of second groove sub-units spaced apart along the second direction, the second groove sub-units corresponding to the semi-enclosed structures; each of the semi-enclosed structures at least partially surrounds a corresponding second groove sub-unit; The third groove penetrates the second electrode layer and the functional layer.

2. The solar cell according to claim 1, wherein Each of the first grooves only includes the semi-enclosed structure, and the multiple semi-enclosed structures included in the first groove are connected in sequence.

3. The solar cell according to claim 1, wherein Each of the first grooved sub-units further includes a connecting portion, and the semi-enclosed structures in two adjacent first grooved sub-units are connected via the connecting portion of the preceding first grooved sub-unit in the two adjacent first grooved sub-units.

4. The solar cell according to claim 3, characterized in that The length of the connecting portion along the second direction is between 0 μm and 10000 μm.

5. The solar cell according to claim 3, characterized in that The lengths of the connecting portions along the second direction are all equal, and the lengths of the openings surrounded by the semi-enclosed structures along the second direction are all equal.

6. The solar cell according to any one of claims 1 to 5, characterized in that: The semi-enclosed structure includes a first oblique side and a second oblique side connected in sequence, and an angle between the first oblique side and the second oblique side is greater than or equal to ninety degrees.

7. The solar cell according to any one of claims 1 to 5, characterized in that: A vertical projection of the second groove subunit overlaps with a vertical projection of the corresponding opening surrounded by the semi-enclosed structure.

8. The solar cell according to any one of claims 1 to 5, characterized in that: The length of the opening surrounded by the semi-enclosed structure along the second direction is between 85 μm and 1000 μm.

9. The solar cell according to any one of claims 1 to 5, characterized in that: The semi-enclosed structure includes a first oblique side and a second oblique side connected in sequence, and the lengths of the first oblique side and the second oblique side are both between 60 μm and 600 μm.

10. The solar cell according to any one of claims 1 to 5, characterized in that: A maximum distance between the first groove and the third groove in the first direction is between 90 μm and 900 μm.

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