Solar cell, photovoltaic module and preparation method of solar cell

Abstract

The invention relates to a solar cell, a photovoltaic module and a preparation method of the solar cell. The solar cell comprises a substrate, a first electrode, a first functional layer, a second electrode, a second functional layer and a third electrode which are arranged in a stacked mode. The first groove, the second groove and the third groove are arranged in the first direction, the orthographic projection of the second groove on the substrate is located between the orthographic projection of the first groove on the substrate and the orthographic projection of the third groove on the substrate, the second groove penetrates through the first functional layer, the second electrode and the second functional layer, a first conductive part is arranged in the second groove, and a second conductive part is arranged in the third groove. The third groove penetrates through the second electrode, the second functional layer and the third electrode; the first direction intersects with the thickness direction of the substrate; the first groove penetrates through the first electrode, the first functional layer and the second electrode, and a separator is arranged in the first groove. Therefore, according to the solar cell, the photovoltaic module and the preparation method of the solar cell provided by the invention, the local short circuit problem of the solar cell can be improved.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular to a solar cell, a photovoltaic module and a method for preparing a solar cell. Background Art

[0002] Solar cells, also known as photovoltaic cells, are semiconductor devices that convert sunlight directly into electrical energy. As they are green and environmentally friendly products that do not cause environmental pollution, and solar energy is a renewable resource, solar cells are a new type of battery with broad development prospects.

[0003] In the related art, perovskite solar cells are solar cells that use perovskite-type organic metal halide semiconductors as light-absorbing materials. Perovskite solar cells have the advantages of high efficiency, low cost, lightness, flexibility and environmental protection. However, the local short circuit problem of the above perovskite solar cells needs to be improved. Summary of the invention

[0004] Based on this, it is necessary to provide a solar cell, a photovoltaic module and a method for preparing a solar cell, which can improve the local short circuit problem of the solar cell.

[0005] In a first aspect, an embodiment of the present application provides a solar cell, including a substrate, and a first electrode, a first functional layer, a second electrode, a second functional layer, and a third electrode stacked on the substrate;

[0006] At least one groove group is arranged in the solar cell; the groove group includes a first groove, a second groove and a third groove arranged along a first direction, the orthographic projection of the second groove on the substrate is located between the orthographic projection of the first groove on the substrate and the orthographic projection of the third groove on the substrate, the second groove runs through the first functional layer, the second electrode and the second functional layer, a first conductive member is arranged in the second groove, the first conductive member electrically connects the first electrode and the third electrode, and the third groove runs through the second electrode, the second functional layer and the third electrode; the first direction intersects with the thickness direction of the substrate;

[0007] The first groove runs through the first electrode, the first functional layer and the second electrode, an isolation member is provided in the first groove, and the isolation member runs through the first electrode, the first functional layer and the second electrode.

[0008] The solar cell provided in the embodiment of the present application has a first groove penetrating the first electrode, the first functional layer and the second electrode. An isolation member is provided in the first groove. The isolation member can reduce or avoid carrier transmission between the second electrodes located on both sides of the isolation member along the first direction, thereby reducing or avoiding the short-circuit current between the second electrode, the second functional layer and the third electrode, improving the local short-circuit problem of the solar cell, improving the performance of the solar cell, and extending the life of the solar cell.

[0009] In one embodiment, the groove group includes a fourth groove, and the orthographic projection of the fourth groove on the substrate is located between the orthographic projection of the first groove on the substrate and the orthographic projection of the third groove on the substrate, and at least partially does not overlap with the orthographic projection of the second groove on the substrate;

[0010] The fourth groove penetrates the first functional layer. A second conductive member is disposed in the fourth groove. The second conductive member electrically connects the first electrode and the second electrode.

[0011] In one embodiment, the orthographic projection of the fourth trench on the substrate is located between the orthographic projection of the first trench on the substrate and the orthographic projection of the second trench on the substrate.

[0012] In one embodiment, the orthographic projection of the fourth trench on the substrate is located between the orthographic projection of the second trench on the substrate and the orthographic projection of the third trench on the substrate.

[0013] In one embodiment, an orthographic projection of the second groove on the substrate and an orthographic projection of the fourth groove on the substrate are arranged at intervals.

[0014] In one embodiment, the orthographic projection of the second groove on the substrate is connected to the orthographic projection of the fourth groove on the substrate, the second groove is connected to the fourth groove, and the first conductive member is in contact with the second conductive member.

[0015] In one embodiment, the first functional layer includes a first perovskite light absorbing layer, the second functional layer includes a second perovskite light absorbing layer, and the band gap width of the first perovskite light absorbing layer is different from the band gap width of the second perovskite light absorbing layer;

[0016] The second electrode comprises a light-transmitting electrode; and / or,

[0017] At least one of the first electrode and the third electrode includes a light-transmitting electrode.

[0018] In a second aspect, an embodiment of the present application provides a photovoltaic module, comprising the solar cell in the above-mentioned first aspect.

[0019] In a third aspect, an embodiment of the present application provides a method for preparing a solar cell, comprising:

[0020] providing a substrate;

[0021] forming a first electrode and a first functional layer on one side of the substrate;

[0022] forming a second electrode on a side of the first functional layer facing away from the substrate;

[0023] forming a first groove; the first groove runs through the first electrode, the first functional layer and the second electrode;

[0024] forming a second functional layer on a side of the second electrode facing away from the substrate;

[0025] forming a second groove; the second groove penetrates the first functional layer, the second electrode and the second functional layer;

[0026] forming a third electrode on a side of the second functional layer facing away from the substrate;

[0027] A third groove is formed; the third groove runs through the second electrode, the second functional layer and the third electrode; wherein the first groove, the second groove and the third groove are spaced apart along the first direction, the orthographic projection of the second groove on the substrate is located between the orthographic projection of the first groove on the substrate and the orthographic projection of the third groove on the substrate, an isolating member is provided in the first groove, the isolating member runs through the first electrode, the first functional layer and the second electrode, a first conductive member is provided in the second groove, and the first conductive member electrically connects the first electrode and the third electrode.

[0028] In one embodiment, after forming a first electrode and a first functional layer on one side of a substrate and before forming a second electrode on a side of the first functional layer facing away from the substrate, the method comprises:

[0029] A fourth groove is formed, the fourth groove runs through the first functional layer; a second conductive member is disposed in the fourth groove, and the second conductive member is electrically connected to the first electrode and the second electrode;

[0030] The orthographic projection of the fourth groove on the substrate is located between the orthographic projection of the first groove on the substrate and the orthographic projection of the third groove on the substrate, and at least partially does not overlap with the orthographic projection of the second groove on the substrate.

[0031] In one embodiment, forming a second electrode on a side of the first functional layer facing away from the substrate comprises:

[0032] A second electrode is formed on a side of the first functional layer facing away from the substrate, the second electrode fills the fourth groove, and forms a second conductive member.

[0033] In one embodiment, forming the second functional layer on a side of the second electrode facing away from the substrate comprises:

[0034] A third transmission layer, a second perovskite light absorption layer and a fourth transmission layer are formed on a side of the second electrode facing away from the substrate, the third transmission layer and the second perovskite light absorption layer fill the first groove and form an isolation member, and / or,

[0035] Forming the third electrode on the side of the second functional layer facing away from the substrate includes: forming the third electrode on the side of the second functional layer facing away from the substrate, the third electrode filling the second groove, and forming a first conductive member. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A cross-sectional view of a solar cell provided in an embodiment of the present application.

[0037] Figure 2 Another cross-sectional view of a solar cell provided in an embodiment of the present application.

[0038] Figure 3 A schematic diagram of the structure after the fourth groove is formed provided in an embodiment of the present application.

[0039] Figure 4 A schematic diagram of the structure after the second electrode is formed according to an embodiment of the present application.

[0040] Figure 5 A schematic diagram of the structure after the first groove is formed provided in an embodiment of the present application.

[0041] Figure 6 A schematic diagram of the structure after the second functional layer is formed according to an embodiment of the present application.

[0042] Figure 7 A schematic diagram of the structure after the second groove is formed provided in an embodiment of the present application.

[0043] Figure 8 This is a schematic diagram of the structure after the third electrode is formed according to an embodiment of the present application.

[0044] Fig. 9 A schematic diagram of the process of preparing a solar cell provided in an embodiment of the present application.

[0045] Description of reference numerals:

[0046] 100. Solar cell; 110. First functional layer; 111. First transmission layer; 112. Second transmission layer; 113. First perovskite light absorbing layer; 120. Second functional layer; 122. Second perovskite light absorbing layer; 123. Third transmission layer; 124. Fourth transmission layer; 131. First electrode; 132. Second electrode; 133. Third electrode; 140. Substrate; 150. Groove group; P1. First groove; P2. Second groove; P3. Third groove; P4. Fourth groove; 161. First conductive member; 162. Second conductive member; 163. Isolating member. DETAILED DESCRIPTION

[0047] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0048] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0049] It should be noted that, if an element is referred to as being “disposed on” another element, it may be directly on the other element or there may be an element centered therebetween.

[0050] In the related art, a solar cell may include a stacked substrate, a first electrode, a first functional layer, a second electrode, a second functional layer and a third electrode, the solar cell has a plurality of groove groups arranged at intervals, the groove groups include a first groove, a second groove and a third groove, and the orthographic projection of the second groove on the substrate is located between the orthographic projection of the first groove on the substrate and the orthographic projection of the third groove on the substrate. The first groove penetrates the first electrode along the thickness direction of the substrate, the second groove penetrates the first functional layer, the second electrode and the second functional layer along the thickness direction of the substrate, and the third groove penetrates the second electrode, the second functional layer and the third electrode along the thickness direction of the substrate. An insulating member is provided in the first groove, and a conductive member is provided in the second groove, and both ends of the conductive member are electrically connected to the first electrode and the third electrode respectively.

[0051] However, the conductive member is also electrically connected to the second electrode, resulting in a short-circuit loop being formed between the third electrode, the conductive member between the second electrode and the third electrode, the second electrode and the second functional layer, resulting in a short-circuit current in the short-circuit loop, causing a local short-circuit problem in the solar cell, thereby adversely affecting the performance and life of the solar cell.

[0052] To solve the above problems, the embodiments of the present application provide a solar cell, a photovoltaic module and a method for preparing a solar cell, which can improve the local short circuit problem of the solar cell.

[0053] The following will be combined Figure 1-Figure 9 The solar cell 100, the photovoltaic module and the method for preparing the solar cell 100 provided in the embodiments of the present application are described.

[0054] See also Figure 1, an embodiment of the present application provides a solar cell 100, and the solar cell 100 may have a first direction X, a second direction Y and a third direction Z, and the first direction X, the second direction Y and the third direction Z are all different. The first direction X, the second direction Y and the third direction Z may be perpendicular to each other. For example, the third direction Z may be the thickness direction of the solar cell 100, and the first direction X and the second direction Y may be any two different directions perpendicular to the thickness direction of the solar cell 100. The first direction X may be the length direction of the solar cell 100, and the second direction Y may be the width direction of the solar cell 100. The length, width and thickness in the embodiments of the present application are merely for the convenience of description and do not imply any limitation on the size. For example, the width may be greater than, equal to or less than the length. The direction of the solar cell 100 may be consistent with the direction of the film layer such as the substrate 140.

[0055] See also Figure 1 The solar cell 100 includes a substrate 140 , which can provide support for subsequently formed film layers.

[0056] Exemplarily, the material of the substrate 140 includes at least one of inorganic materials such as glass, quartz, carbon, silicon, etc., or organic materials such as polyethylene terephthalate (eg, organic flexible material).

[0057] See also Figure 1 The solar cell 100 may include a first electrode 131, a first functional layer 110, a second electrode 132, a second functional layer 120 and a third electrode 133 stacked in a direction away from the substrate 140, so that the solar cell 100 may form a double-junction stacked solar cell 100. The solar cell 100 may include a plurality of sub-cells, the plurality of sub-cells are arranged in a first direction X, and the sub-cells are double-junction stacked sub-cells.

[0058] See also Figure 1 At least one groove group 150 is arranged on the solar cell 100. When there are multiple groove groups 150, the multiple groove groups 150 are arranged at intervals along the first direction X. By providing multiple groove groups 150, the solar cell 100 forms multiple sub-cells arranged along the first direction X.

[0059] See also Figure 1 The groove group 150 may include a first groove P1, a second groove P2 and a third groove P3 arranged along the first direction X, and the orthographic projection of the second groove P2 on the substrate 140 may be located between the orthographic projection of the first groove P1 on the substrate 140 and the orthographic projection of the third groove P3 on the substrate 140.

[0060] The first groove P1 at least penetrates the first electrode 131, and an isolation member 163 is disposed in the first groove P1. The isolation member 163 at least penetrates the first electrode 131, and the first groove P1 can separate the first electrodes 131 of two adjacent sub-cells. The third groove P3 penetrates the second electrode 132, the second functional layer 120, and the third electrode 133, and the second electrodes 132, the second functional layer 120, and the third electrode 133 of two adjacent sub-cells can be separated by the third groove P3. In this way, the first groove P1 and the third groove P3 can separate the two adjacent sub-cells into the first sub-cell and the second sub-cell arranged along the first direction X. For example, the first sub-cell can be Figure 1 The second sub-battery can be Figure 1 The sub-cell on the right side of the middle. The second groove P2 runs through the first functional layer 110, the second electrode 132 and the second functional layer 120. The first conductive member 161 is provided in the second groove P2. One end of the first conductive member 161 can be electrically connected to the first electrode 131, and the other end of the first conductive member 161 can be electrically connected to the third electrode 133. For example, one end of the first conductive member 161 can be electrically connected to the first electrode 131, and the other end of the first conductive member 161 can be electrically connected to the third electrode 133. The two ends of the first conductive member 161 can electrically connect the third electrode 133 of the first sub-cell to the first electrode 131 of the second sub-cell, respectively, so as to connect two adjacent sub-cells in series through the first conductive member 161. In summary, by providing the first groove P1, the second groove P2 and the third groove P3, and providing the first conductive member 161 in the second groove P2, the series connection of multiple sub-cells of the solar cell 100 can be achieved. The solar cell 100 provided in the embodiment of the present application not only has a stable interconnection structure, but also has a process route consistent with that of a single-cell solar cell 100, has fewer process steps, does not require iterative equipment, and is mature in technology and can be mass-produced.

[0061] in, Figure 1 The arrow i in the middle shows the transport direction of at least part of the carriers in two adjacent sub-cells.

[0062] Exemplarily, the first conductive member 161 and the third electrode 133 may be prepared in steps, or the first conductive member 161 and the third electrode 133 may be prepared simultaneously, and the first conductive member 161 may be formed by extending a portion of the third electrode 133 into the second trench P2.

[0063] In the related art, the first groove P1 only penetrates the first electrode 131 but not the second electrode 132. In the first sub-cell of two adjacent sub-cells, a short-circuit loop is formed between the second electrode 132, the third electrode 133 and the second functional layer 120, which causes a short-circuit current in the short-circuit loop, resulting in a local short-circuit problem in the solar cell, which in turn has an adverse effect on the performance and life of the solar cell.

[0064] See also Figure 1 , the first groove P1 may also penetrate the second electrode 132, and an isolation member 163 is provided in the first groove P1, and the isolation member 163 may also penetrate the second electrode 132 to isolate the second electrode 132. In the first sub-cell of two adjacent sub-cells, the isolation member 163 may reduce or avoid the carrier transmission between the second electrodes 132 located on both sides of the isolation member 163 along the first direction X, thereby reducing or avoiding the short-circuit current between the second electrode 132, the second functional layer 120 and the third electrode 133, improving the local short-circuit problem of the solar cell 100, improving the performance of the solar cell 100, and extending the life of the solar cell 100. Wherein, see Figure 2 If the isolation member 163 is not provided, the carrier di will be transmitted from the second electrode 132 in the area on the right side of the isolation member 163 to the second electrode 132 in the area on the left side of the isolation member 163, and a short-circuit current will be formed. By providing the isolation member 163, the short-circuit current can be reduced or avoided.

[0065] For example, the material of the isolation member 163 may be an insulating material.

[0066] Alternatively, the material of the spacer 163 may be the same as the material of at least a portion of the second functional layer 120, so as to facilitate the simultaneous preparation of the spacer 163 and the second functional layer 120, thereby simplifying the preparation process and cost of the solar cell 100. For example, the spacer 163 may be formed by the third transmission layer 123 and the second perovskite light absorption layer 122 extending into the first trench P1.

[0067] In some embodiments, see Figure 1 The first groove P1 can also penetrate the first functional layer 110, and the isolation member 163 can also penetrate the first functional layer 110, that is, the first groove P1 and the isolation member 163 can simultaneously penetrate the first electrode 131, the first functional layer 110 and the second electrode 132, so that the first groove P1 is an integrated structure, which can simplify the preparation process of the first groove P1 and reduce the preparation cost.

[0068] In some other embodiments, the first groove P1 may include a first sub-groove and a second sub-groove, the first sub-groove passes through the first electrode 131, and the first sub-groove is used to separate the first electrodes 131 of two adjacent sub-cells, the second sub-groove passes through the second electrode 132, and the second sub-groove is used to improve the local short circuit problem of the solar cell 100, and the first sub-groove and the second sub-groove are spaced apart along the thickness direction of the substrate 140, so that the first groove P1 is divided into two independent sub-grooves, and the first sub-groove and the second sub-groove can be prepared separately.

[0069] The embodiment of the present application is described by taking an example in which the first trench P1 penetrates the first electrode 131 , the first functional layer 110 and the second electrode 132 at the same time.

[0070] It should be noted that since the second groove P2 penetrates the first functional layer 110, the second functional layer 120 and the second electrode 132 along the thickness direction of the substrate 140, the depth of the second groove P2 along the thickness direction of the substrate 140 is relatively large. In the process of forming the first electrode 131, it is not easy for the first conductive member 161 to completely fill the second groove P2. In particular, the portion of the second groove P2 close to the first electrode 131 is not easy to be completely filled by the first conductive member 161, resulting in a smaller cross-sectional area of ​​the portion of the first conductive member 161 close to the first electrode 131, thereby resulting in a larger resistance of the first conductive member 161, resulting in a larger current transmission loss of the solar cell 100.

[0071] In some embodiments, the groove group 150 may include a fourth groove P4, and the orthographic projection of the fourth groove P4 on the substrate 140 may be located between the orthographic projection of the first groove P1 on the substrate 140 and the orthographic projection of the third groove P3 on the substrate 140, and the orthographic projection of the fourth groove P4 on the substrate 140 does not overlap at least partially with the orthographic projection of the second groove P2 on the substrate 140. The fourth groove P4 may penetrate the first functional layer 110, and a second conductive member 162 is disposed in the fourth groove P4. One end of the second conductive member 162 may be electrically connected to the second electrode 132, and the other end of the second conductive member 162 may be electrically connected to the first electrode 131. In this way, by setting the fourth groove P4 and providing the second conductive member 162 in the fourth groove P4, the second conductive member 162 can increase the cross-sectional area of ​​the portion of the first conductive member 161 located between the first electrode 131 and the second electrode 132, and the second conductive member 162 and the first conductive member 161 can be connected in parallel, which is beneficial to reducing the resistance of the first conductive member 161, thereby reducing the current transmission loss of the solar cell 100.

[0072] Exemplarily, the second conductive member 162 and the second electrode 132 may be prepared in steps. Alternatively, the second conductive member 162 and the second electrode 132 may be prepared simultaneously, and the second conductive member 162 may be formed by extending a portion of the second electrode 132 into the fourth trench P4.

[0073] In some embodiments, see Figure 1 The orthographic projection of the fourth trench P4 on the substrate 140 is located between the orthographic projection of the second trench P2 on the substrate 140 and the orthographic projection of the third trench P3 on the substrate 140 .

[0074] In some embodiments, see Figure 2The orthographic projection of the fourth trench P4 on the substrate 140 is located between the orthographic projection of the first trench P1 on the substrate 140 and the orthographic projection of the second trench P2 on the substrate 140 .

[0075] In the same trench group 150 , the fourth trench P4 may be disposed on at least one side of the second trench P2 along the first direction X. The present embodiment takes the fourth trench P4 of the same trench group 150 disposed on one side of the second trench P2 along the first direction X as an example for description.

[0076] In some embodiments, see Figure 1 The orthographic projection of the second groove P2 on the substrate 140 and the orthographic projection of the fourth groove P4 on the substrate 140 are arranged at intervals, which can prevent damage to the second conductive member 162 in the fourth groove P4 when preparing the second groove P2, and is also conducive to reducing the difficulty of preparing the second groove P2 and the fourth groove P4.

[0077] In some other embodiments, the orthographic projection of the second groove P2 on the substrate 140 is connected to the orthographic projection of the fourth groove P4 on the substrate 140, the second groove P2 and the fourth groove P4 are connected, and the first conductive member 161 and the second conductive member 162 are in contact. This is beneficial to reduce the total area of ​​the solar cell 100 occupied by the second groove P2 and the fourth groove P4 along the first direction X, reduce the area of ​​the solar cell 100 occupied by the spacing area between the second groove P2 and the fourth groove P4 along the first direction X, and help reduce the size of the solar cell 100 along the first direction X.

[0078] In some embodiments, see Figure 1 , the first functional layer 110 may include a first transport layer 111, a first perovskite light absorbing layer 113, and a second transport layer 112 arranged in a direction away from the substrate 140, and the second functional layer 120 includes a third transport layer 123, a second perovskite light absorbing layer 122, and a fourth transport layer 124 arranged in a direction away from the substrate 140. The first transport layer 111 and the third transport layer 123 include electron transport layers, and the second transport layer 112 and the fourth transport layer 124 include hole transport layers, or the first transport layer 111 and the third transport layer 123 include hole transport layers, and the second transport layer 112 and the fourth transport layer 124 include electron transport layers.

[0079] In some embodiments, the band gap width of the first perovskite light absorption layer 113 is different from the band gap width of the second perovskite light absorption layer 122. By setting the first perovskite light absorption layer 113 and the second perovskite light absorption layer 122 with different band gap widths, the first perovskite light absorption layer 113 and the second perovskite light absorption layer 122 can utilize sunlight of different wavelengths, so that the solar cell 100 can absorb sunlight of a wider range of wavelengths, reduce photon thermal loss, and improve the photoelectric conversion efficiency of the solar cell 100, thereby surpassing the theoretical efficiency limit of the single-junction solar cell 100.

[0080] Exemplarily, the material of at least one of the first perovskite light absorbing layer 113 and the second perovskite light absorbing layer 122 includes perovskite, and the structural formula of the perovskite can be ABX3. Wherein, A includes organic cations, inorganic cations, or organic-inorganic mixed cations, B includes organic cations, inorganic cations, or organic-inorganic mixed cations, and X includes anions. For example, A includes CH3NH3 + 、CH(NH2)2 + , Li + 、Na + , K + , Rb + and Cs + At least one of, B includes Pb 2+ Sn 2+ 、Be 2+ Mg 2+ , Ca 2+ , Sr 2+ , Ba 2+ 、Zn 2+ ,Ge 2+ , Fe 2+ 、Co 2+ and Ni 2+ At least one of X includes F - , Cl - Br - and I - At least one of .

[0081] In some embodiments, the second electrode 132 includes a light-transmitting electrode, and at least one of the first electrode 131 and the third electrode 133 includes a light-transmitting electrode, so that both the first perovskite light-absorbing layer 113 and the second perovskite light-absorbing layer 122 can be illuminated by sunlight.

[0082] Exemplarily, the second electrode 132 material may include at least one of indium tin oxide (ITO), aluminum zinc oxide (AZO), gallium aluminum zinc oxide (GAZO), tin oxide (SnO 2 ), antimony tin oxide (ATO), fluorine tin oxide (FTO), cerium indium oxide (ICO), and aluminum indium oxide (IWO).

[0083] Exemplarily, the material of one of the first electrode 131 and the third electrode 133 may include at least one of ITO, AZO, GAZO, SnO2, ATO, FTO, ICO, and IWO, and the material of the other may include at least one of Cu, Ag, Au, Al, carbon electrode, carbon nanotube, ITO, AZO, GAZO, SnO2, ATO, FTO, ICO, and IWO.

[0084] The photovoltaic module provided in the embodiments of the present application is described below.

[0085] The embodiment of the present application further provides a photovoltaic module, which may include a solar cell 100. There may be at least one solar cell 100 in the photovoltaic module. The embodiment of the present application takes the photovoltaic module as an example in which there are multiple solar cells 100, and the multiple solar cells 100 together constitute a battery string layer.

[0086] In some embodiments, the photovoltaic module may include a first encapsulation member and a second encapsulation member located on both sides of the battery string layer, and the first encapsulation member and the second encapsulation member encapsulate the battery string layer to protect the battery string layer. The first encapsulation member and the second encapsulation member may include an encapsulation adhesive layer and a cover plate, the encapsulation adhesive layer is located on the side of the cover plate facing the battery string layer, the cover plate can protect the battery string layer, and the encapsulation adhesive layer can be used to connect the cover plate and the battery string layer.

[0087] Exemplarily, the solar cell 100 may include a perovskite solar cell.

[0088] The following is an explanation of a method for preparing the solar cell 100 provided in an embodiment of the present application.

[0089] The present application embodiment provides a method for preparing a solar cell 100, which is used to prepare the solar cell 100 in the above embodiment. Fig. 9 , the preparation method may include:

[0090] S100: providing a substrate.

[0091] See also Figure 3 , providing a substrate 140, which can provide support for the film layer formed subsequently.

[0092] S200: forming a first electrode and a first functional layer on one side of the substrate.

[0093] See also Figure 3 After providing the substrate 140 , the method may include forming a first electrode 131 on one side of the substrate 140 , and forming a first functional layer 110 on a side of the first electrode 131 facing away from the substrate 140 .

[0094] In some embodiments, the electrode (taking the first electrode 131 as an example) preparation method includes deposition. Deposition may include atomic layer deposition (atomic layer deposition, referred to as ALD), physical vapor deposition (physical vapor deposition, referred to as PVD) (for example, evaporation, magnetron sputtering), chemical vapor deposition (chemical vapor deposition, referred to as CVD), etc. Other structural layers in the embodiments of the present disclosure may also be formed by deposition, which will not be described in detail.

[0095] For example, physical vapor deposition may include evaporation, sputtering (eg, magnetron sputtering), and the like.

[0096] For example, the first electrode 131 is formed by sputtering.

[0097] In some embodiments, forming the first functional layer 110 may include sequentially forming a first transmission layer 111 , a first perovskite light absorption layer 113 , and a second transmission layer 112 on a side of the first electrode 131 facing away from the substrate 140 .

[0098] In some embodiments, the preparation method of the transport layer (taking the first transport layer 111 as an example) may include deposition. For example, the hole transport layer may be prepared by sputtering, and the electron transport layer may be prepared by evaporation.

[0099] In some embodiments, the preparation method of the perovskite light absorbing layer (taking the first perovskite light absorbing layer 113 as an example) may include at least one of deposition, spin coating, blade coating, evaporation, printing, spray coating, spray pyrolysis and slit coating.

[0100] S300: forming a second electrode on a side of the first functional layer facing away from the substrate.

[0101] See also Figure 4 After forming the first electrode 131 and the first functional layer 110 on one side of the substrate 140 , the method may include forming a second electrode 132 on a side of the first functional layer 110 facing away from the substrate 140 .

[0102] S400: forming a first trench; the first trench penetrates the first electrode, the first functional layer and the second electrode.

[0103] See also Figure 5 After forming the second electrode 132 on the side of the first functional layer 110 facing away from the substrate 140 , the method may include forming a first trench P1 , where the first trench P1 may penetrate the first electrode 131 , the first functional layer 110 , and the second electrode 132 .

[0104] In some embodiments, the preparation method of the groove (taking the first groove P1 as an example) may include laser scribing or mechanical scribing, etc. The laser light source for laser scribing includes at least one of nanosecond infrared, picosecond green light, picosecond infrared, femtosecond green light and femtosecond infrared.

[0105] S500: forming a second functional layer on a side of the second electrode facing away from the substrate.

[0106] See also Figure 6 After forming the first trench P1 , the method may include forming a second functional layer 120 on a side of the second electrode 132 facing away from the substrate 140 .

[0107] In some embodiments, forming the second functional layer 120 on the side of the second electrode 132 facing away from the substrate 140 may include sequentially forming a third transmission layer 123 , a second perovskite light absorption layer 122 and a fourth transmission layer 124 on the side of the second electrode 132 facing away from the substrate 140 .

[0108] S600: forming a second groove; the second groove penetrates the first functional layer, the second electrode and the second functional layer.

[0109] See also Figure 7 After forming the second functional layer 120 on the side of the second electrode 132 facing away from the substrate 140 , the method may include forming a second trench P2 . The second trench P2 may penetrate the first functional layer 110 , the second electrode 132 , and the second functional layer 120 .

[0110] S700: forming a third electrode on a side of the second functional layer facing away from the substrate.

[0111] See also Figure 8 After forming the second trench P2 , the process may include forming a third electrode 133 on a side of the second functional layer 120 facing away from the substrate 140 .

[0112] S800: forming a third groove; the third groove runs through the second electrode, the second functional layer and the third electrode; wherein the first groove, the second groove and the third groove are spaced apart along the first direction, the orthographic projection of the second groove on the substrate is located between the orthographic projection of the first groove on the substrate and the orthographic projection of the third groove on the substrate, an isolation member is provided in the first groove, and a first conductive member is provided in the second groove.

[0113] See also Figure 1After forming the third electrode 133 on the side of the second functional layer 120 away from the substrate 140, the method may include forming a third groove P3, wherein the third groove P3 penetrates the second electrode 132, the second functional layer 120 and the third electrode 133. The first groove P1, the second groove P2 and the third groove P3 are arranged at intervals along the first direction X, the orthographic projection of the second groove P2 on the substrate 140 is located between the orthographic projection of the first groove P1 on the substrate 140 and the orthographic projection of the third groove P3 on the substrate 140, the first groove P1 is provided with an isolating member 163, and the second groove P2 is provided with a first conductive member 161. In this way, the first groove P1 and the third groove P3 can separate two adjacent sub-cells into a first sub-cell and a second sub-cell arranged along the first direction X, and the first conductive member 161 connects the two adjacent sub-cells in series. In addition, the first groove P1 may penetrate the first electrode 131, the first functional layer 110 and the second electrode 132, and an isolation member 163 is provided in the first groove P1. In the first sub-cell of two adjacent sub-cells, the isolation member 163 may reduce or avoid carrier transmission between the second electrodes 132 located on both sides of the isolation member 163 along the first direction X, thereby reducing or avoiding the short-circuit current between the second electrode 132, the second functional layer 120 and the third electrode 133, improving the local short-circuit problem of the solar cell 100, improving the performance of the solar cell 100, and extending the life of the solar cell 100. The principle has been explained and will not be repeated.

[0114] In some embodiments, see Figure 3 and Figure 4 After forming the first electrode 131 and the first functional layer 110, and before forming the second electrode 132 on the side of the first functional layer 110 away from the substrate 140, the fourth trench P4 may be formed. The fourth trench P4 penetrates the first functional layer 110, and the second conductive member 162 is disposed in the fourth trench P4.

[0115] The orthographic projection of the fourth groove P4 on the substrate 140 is located between the orthographic projection of the first groove P1 on the substrate 140 and the orthographic projection of the third groove P3 on the substrate 140, and at least partially does not overlap with the orthographic projection of the second groove P2 on the substrate 140. One end of the second conductive member 162 can be electrically connected to the second electrode 132, and the other end of the second conductive member 162 can be electrically connected to the first electrode 131. In this way, by providing the fourth groove P4, and the second conductive member 162 is provided in the fourth groove P4, the second conductive member 162 can increase the cross-sectional area of ​​the portion of the first conductive member 161 located between the first electrode 131 and the second electrode 132, and the second conductive member 162 and the first conductive member 161 can be connected in parallel, which is conducive to reducing the resistance of the first conductive member 161, thereby reducing the current transmission loss of the solar cell 100.

[0116] In some embodiments, forming the second electrode 132 on the side of the first functional layer 110 away from the substrate 140 includes forming the second electrode 132 on the side of the first functional layer 110 away from the substrate 140, and the second electrode 132 can also fill at least a portion of the fourth trench P4, and the second electrode 132 located in the fourth trench P4 can form a second conductive member 162. In this way, part of the second electrode 132 is used to form the second conductive member 162, and the second conductive member 162 does not need to be prepared separately, which can simplify the preparation process of the second conductive member 162 and reduce the preparation cost.

[0117] In some embodiments, forming the second functional layer 120 on the side of the second electrode 132 away from the substrate 140 includes forming a third transmission layer 123, a second perovskite light absorption layer 122, and a fourth transmission layer 124 on the side of the second electrode 132 away from the substrate 140, and the third transmission layer 123 and the second perovskite light absorption layer 122 can fill at least a portion of the first trench P1, and the third transmission layer 123 and the second perovskite light absorption layer 122 located in the first trench P1 can form an isolation member 163. In this way, by using part of the second functional layer 120 (for example, the third transmission layer 123 and the second perovskite light absorption layer 122) to form the isolation member 163, there is no need to prepare the isolation member 163 separately, which can simplify the preparation process of the isolation member 163 and reduce the preparation cost.

[0118] It should be noted that, in an embodiment in which the isolation member 163 is formed by a portion of the second functional layer 120, the isolation member 163 may be formed by a portion of the third transmission layer 123, or, the isolation member 163 may be formed by a portion of the third transmission layer 123 and the second perovskite absorption layer 122, or, the isolation member 163 may be formed by a portion of the third transmission layer 123, the second perovskite absorption layer 122 and the fourth transmission layer 124.

[0119] In some embodiments, forming the third electrode 133 on the side of the second functional layer 120 away from the substrate 140 includes forming the third electrode 133 on the side of the second functional layer 120 away from the substrate 140, and the third electrode 133 fills at least a portion of the second trench P2, and the third electrode 133 in the second trench P2 can form the first conductive member 161. In this way, part of the third electrode 133 is used to form the first conductive member 161, and there is no need to prepare the first conductive member 161 separately, which can simplify the preparation process of the first conductive member 161 and reduce the preparation cost.

[0120] In some embodiments, after the third trench P3 is formed, the solar cell 100 may be cleaned and packaged.

[0121] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0122] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A solar cell, characterized in that: It includes a substrate and a first electrode, a first functional layer, a second electrode, a second functional layer and a third electrode stacked on the substrate; The solar cell further comprises at least one groove group, the groove group comprises a first groove, a second groove and a third groove arranged along a first direction, the orthographic projection of the second groove on the substrate is located between the orthographic projection of the first groove on the substrate and the orthographic projection of the third groove on the substrate, the second groove penetrates the first functional layer, the second electrode and the second functional layer, a first conductive member is provided in the second groove, the first conductive member electrically connects the first electrode and the third electrode, the third groove penetrates the second electrode, the second functional layer and the third electrode; the first direction intersects with the thickness direction of the substrate; The first groove runs through the first electrode, the first functional layer and the second electrode, an isolation member is provided in the first groove, and the isolation member runs through the first electrode, the first functional layer and the second electrode.

2. The solar cell according to claim 1, characterized in that The groove group includes a fourth groove, the orthographic projection of the fourth groove on the substrate is located between the orthographic projection of the first groove on the substrate and the orthographic projection of the third groove on the substrate, and at least partially does not overlap with the orthographic projection of the second groove on the substrate; The fourth groove penetrates the first functional layer. A second conductive member is disposed in the fourth groove. The second conductive member electrically connects the first electrode and the second electrode.

3. The solar cell according to claim 2, characterized in that: The orthographic projection of the fourth groove on the substrate is located between the orthographic projection of the first groove on the substrate and the orthographic projection of the second groove on the substrate.

4. The solar cell according to claim 2, characterized in that: The orthographic projection of the fourth groove on the substrate is located between the orthographic projection of the second groove on the substrate and the orthographic projection of the third groove on the substrate.

5. The solar cell according to any one of claims 2 to 4, characterized in that: The orthographic projection of the second groove on the substrate and the orthographic projection of the fourth groove on the substrate are arranged at intervals.

6. The solar cell according to any one of claims 2 to 4, characterized in that: The orthographic projection of the second groove on the substrate is connected to the orthographic projection of the fourth groove on the substrate, the second groove is communicated with the fourth groove, and the first conductive member is in contact with the second conductive member.

7. The solar cell according to any one of claims 1 to 4, characterized in that: The first functional layer includes a first perovskite light absorbing layer, the second functional layer includes a second perovskite light absorbing layer, and the band gap width of the first perovskite light absorbing layer is different from the band gap width of the second perovskite light absorbing layer; The second electrode comprises a light-transmitting electrode; and / or, At least one of the first electrode and the third electrode includes a light-transmitting electrode.

8. A photovoltaic module, characterized in that: A solar cell comprising any one of claims 1 to 7.

9. A method for preparing a solar cell, characterized in that: include: providing a substrate; forming a first electrode and a first functional layer on one side of the substrate; forming a second electrode on a side of the first functional layer facing away from the substrate; forming a first trench; The first groove runs through the first electrode, the first functional layer and the second electrode; forming a second functional layer on a side of the second electrode facing away from the substrate; forming a second trench; The second groove runs through the first functional layer, the second electrode and the second functional layer; forming a third electrode on a side of the second functional layer facing away from the substrate; forming a third groove; The third groove runs through the second electrode, the second functional layer and the third electrode; wherein the first groove, the second groove and the third groove are spaced apart along the first direction, the orthographic projection of the second groove on the substrate is located between the orthographic projection of the first groove on the substrate and the orthographic projection of the third groove on the substrate, an isolating member is provided in the first groove, the isolating member runs through the first electrode, the first functional layer and the second electrode, a first conductive member is provided in the second groove, and the first conductive member electrically connects the first electrode and the third electrode.

10. The method for preparing a solar cell according to claim 9, characterized in that: After forming the first electrode and the first functional layer on one side of the substrate and before forming the second electrode on the side of the first functional layer facing away from the substrate, the method comprises: forming a fourth groove, wherein the fourth groove penetrates the first functional layer; a second conductive member is disposed in the fourth groove, and the second conductive member electrically connects the first electrode and the second electrode; The orthographic projection of the fourth groove on the substrate is located between the orthographic projection of the first groove on the substrate and the orthographic projection of the third groove on the substrate, and at least partially does not overlap with the orthographic projection of the second groove on the substrate.

11. The method for preparing a solar cell according to claim 10, characterized in that: The forming of a second electrode on a side of the first functional layer away from the substrate comprises: The second electrode is formed on a side of the first functional layer facing away from the substrate, and the second electrode fills the fourth groove and forms the second conductive member.

12. The method for preparing a solar cell according to any one of claims 9 to 11, characterized in that: The forming of a second functional layer on a side of the second electrode facing away from the substrate comprises: A third transmission layer, a second perovskite light absorption layer and a fourth transmission layer are formed on a side of the second electrode away from the substrate, wherein the third transmission layer and the second perovskite light absorption layer fill the first groove and form the isolation member, and / or The forming of the third electrode on the side of the second functional layer away from the substrate includes: forming the third electrode on the side of the second functional layer away from the substrate, the third electrode filling the second groove and forming the first conductive member.

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