Solar cells, laminated cells and photovoltaic modules

Abstract

The present disclosure relates to the field of photovoltaics, and provides a solar cell, a laminated cell and a photovoltaic module. The solar cell comprises a substrate, a doped conductive layer, a first grid line and a second grid line. The doped conductive layer is on the substrate; the first grid line is on the substrate and in electrical contact with the doped conductive layer, the orthographic projection of the first grid line on the substrate is a wave shape or a zigzag shape having multiple inflection points, the first grid line comprises multiple first segments and second segments which are alternately distributed, the distance between adjacent inflection points in the first segment along a first direction is less than the distance between adjacent inflection points in the second segment along the first direction; the second grid line is on the substrate, the second grid line extends along a second direction and is connected with the first segment. The present disclosure can at least improve the performance of the solar cell.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the field of photovoltaics, and in particular to a solar cell, a stacked cell and a photovoltaic module. BACKGROUND

[0002] With the gradual depletion of fossil energy, solar energy is used more and more widely as a new energy alternative. A solar cell is a device that converts the light energy of the sun into electrical energy. The solar cell uses the photovoltaic principle to generate carriers, and then uses electrodes to lead out the carriers, thereby facilitating the effective use of electrical energy.

[0003] However, the current fine grid design in the solar cell has problems, resulting in the performance of the solar cell to be improved. SUMMARY

[0004] The embodiments of the present disclosure provide a solar cell, a stacked cell and a photovoltaic module, which at least facilitate improving the performance of the solar cell.

[0005] According to some embodiments of the present disclosure, the embodiments of the present disclosure provide a solar cell. The solar cell comprises: a substrate; a doped conductive layer located on the substrate; a first grid line located on the substrate and in electrical contact with the doped conductive layer, a normal projection of the first grid line on the substrate being a wave shape or a sawtooth shape having a plurality of inflection points, the first grid line comprising a plurality of first segments and second segments alternately distributed, a distance between adjacent inflection points in the first segment in a first direction being less than a distance between adjacent inflection points in the second segment in the first direction; and a second grid line located on the substrate, the second grid line extending in a second direction and connected with the first segment.

[0006] In some embodiments, in a direction close to the first segment, the distance between adjacent inflection points in the second segment in the first direction gradually decreases.

[0007] In some embodiments, the distance between adjacent inflection points in the first segment in the first direction is 0.25mm-0.75mm, and the distance between adjacent inflection points in the second segment in the first direction is 0.76mm-1.5mm.

[0008] In some embodiments, the distance between adjacent inflection points in the second direction is 0.1mm-0.5mm.

[0009] In some embodiments, the solar cell further comprises: a passivation layer on a surface of the doped conductive layer facing away from the substrate, a recess is arranged in the passivation layer, the first grid line and the second grid line are cross-connected, and a cross section of the first grid line and the second grid line is located in the recess.

[0010] In some embodiments, a width of the recess along the first direction is greater than a width of the second grid line along the first direction, and a width of the recess along the second direction is greater than a width of the first grid line along the second direction.

[0011] In some embodiments, the substrate comprises two oppositely arranged first edges, and a width of the second grid line close to the first edge along the first direction is greater than a width of the second grid line away from the first edge along the first direction.

[0012] In some embodiments, the second grid line comprises a main body portion and edge portions at two ends of the main body portion, the edge portions comprise a first end close to the main body portion and a second end away from the main body portion, a width of the first end along the first direction is equal to a width of the main body portion along the first direction, a width of the second end along the first direction is less than a width of the main body portion along the first direction, and a width of the edge portion along the first direction gradually increases in a direction close to the main body portion.

[0013] According to some embodiments of the present disclosure, another aspect of the embodiments of the present disclosure further provides a stacked cell. The stacked cell comprises: a bottom cell, which is the solar cell according to any one of the above embodiments; and a top cell, which is located on the bottom cell.

[0014] According to some embodiments of the present disclosure, still another aspect of the embodiments of the present disclosure further provides a photovoltaic module. The photovoltaic module comprises: a cell string, which is connected by a plurality of solar cells according to any one of the above embodiments or connected by stacked cells according to the above embodiments; an encapsulation film, which is used to cover a surface of the cell string; and a cover plate, which is used to cover a surface of the encapsulation film facing away from the cell string.

[0015] The technical solutions provided by the embodiments of the present disclosure have at least the following advantages:

[0016] In the solar cell provided by the embodiments of the present disclosure, the first grid line is in a wave shape or a zigzag shape in the orthographic projection on the substrate, that is, the structure of the first grid line is in a wave shape or a zigzag shape, which is conducive to multiple reflections of the incident light on the surface of the first grid line, so that part of the incident light can be absorbed by the substrate after reflection, thereby helping the substrate to absorb more incident light, improving the light absorption rate of the solar cell, and improving the performance of the solar cell.

[0017] In addition, the first segment of the first grid line is connected with the second grid line, and the distance between adjacent inflection points in the first segment along the first direction is smaller than the distance between adjacent inflection points in the second segment along the first direction. On the one hand, the distance between adjacent inflection points in the first segment along the first direction is small, and the orthographic projection area of the first segment on the substrate is large. That is, the contact area of the first segment with the doped conductive layer can be large, the first segment can collect more current, and the first segment can transmit the more collected current to the second grid line. Thus, it is conducive to improving the efficiency of the solar cell in collecting current, and further improving the performance of the solar cell. On the other hand, the distance between adjacent inflection points in the second segment along the first direction is large, and the orthographic projection area of the second segment on the substrate is small, which can reduce the light blocking area of the second segment, thereby also being conducive to improving the performance of the solar cell. BRIEF DESCRIPTION OF DRAWINGS

[0018] One or more embodiments are illustrated by way of example in the figures that form a part of this disclosure and which are not intended to limit the scope of the embodiments, unless otherwise specifically indicated, the drawings in which:

[0019] Figure 1 A cross-sectional structure schematic diagram of the solar cell provided by the embodiments of the present disclosure;

[0020] Figure 2 A top view structure schematic diagram of the solar cell provided by the embodiments of the present disclosure;

[0021] Figure 3 A top view structure schematic diagram of the solar cell provided by the embodiments of the present disclosure; Figure 2 A partial enlarged schematic diagram of part A in FIG. 4;

[0022] Figure 4 A top view structure schematic diagram of the solar cell provided by the embodiments of the present disclosure;

[0023] Figure 5 A top view structure schematic diagram of the solar cell provided by the embodiments of the present disclosure; Figure 4 A partial enlarged schematic diagram of part B in FIG. 5;

[0024] Figure 6 Another cross-sectional structure diagram of a solar cell provided by an embodiment of the present disclosure is shown in FIG. 6.

[0025] Figure 7 A top view structure diagram of a conductive part in a solar cell provided by an embodiment of the present disclosure is shown in FIG. 7.

[0026] Figure 8 A structure diagram of a second grid line in a solar cell provided by an embodiment of the present disclosure is shown in FIG. 8.

[0027] Figure 9 A structure diagram of a stacked cell provided by an embodiment of the present disclosure is shown in FIG. 9.

[0028] Figure 10 A structure diagram of a photovoltaic module provided by an embodiment of the present disclosure is shown in FIG. 10.

[0029] Legend of reference signs:

[0030] 100, substrate; 110, first surface; 120, second surface; 130, first edge; 101, doped conductive layer; 102, first grid line; 112, first segment; 122, second segment; 103, second grid line; 113, main body part; 123, edge part; 133, first end; 143, second end; 104, passivation layer; 114, groove; 105, conductive part; 106, bottom cell; 107, top cell; 20, solar cell; 21, encapsulation film; 22, cover plate; 23, solder strip. DETAILED DESCRIPTION

[0031] In the current solar cell, the fine grid is usually linear, and the linear fine grid is difficult to help the substrate absorb more incident light, so that the solar cell has a low light absorption rate and poor performance.

[0032] In the solar cell provided by an embodiment of the present disclosure, the first grid line is in a wave shape or a sawtooth shape in the orthographic projection of the substrate, that is, the structure of the first grid line is in a wave shape or a sawtooth shape, which is conducive to multiple reflections of incident light on the surface of the first grid line, so that part of the incident light can be absorbed by the substrate after reflection, thereby helping the substrate to absorb more incident light, improving the light absorption rate of the solar cell, and improving the performance of the solar cell.

[0033] In addition, the first segment of the first gate line is connected with the second gate line, and the distance between adjacent inflection points in the first segment along the first direction is less than the distance between adjacent inflection points in the second segment along the first direction. On the one hand, the distance between adjacent inflection points in the first segment along the first direction is small, so that the area of the orthogonal projection of the first segment on the base is large. That is, the contact area of the first segment with the doped conductive layer can be large, the first segment can collect more current, and the first segment can transmit the more current collected to the second gate line. Thus, it is beneficial to improve the efficiency of the solar cell in collecting current, and thus improve the performance of the solar cell. On the other hand, the distance between adjacent inflection points in the second segment along the first direction is large, so that the area of the orthogonal projection of the second segment on the base is small, which can reduce the shading area of the second segment, and thus also beneficial to improve the performance of the solar cell.

[0034] In the description of the embodiments of the present disclosure, the technical terms "first", "second", and the like are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present disclosure, the meaning of "a plurality of" is two or more, unless otherwise explicitly and specifically limited.

[0035] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present disclosure. The appearance of the phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily independent or alternative to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0036] In the description of the embodiments of the present disclosure, the term "and / or" is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent: A exists, A and B exist, and B exists. In addition, the character " / " herein generally represents that the front and rear associated objects are in an "or" relationship.

[0037] In the description of the embodiments of the present disclosure, the term "a plurality of" refers to two or more (including two), and similarly, "a plurality of groups" refers to two or more groups (including two groups), and "a plurality of pieces" refers to two or more pieces (including two pieces).

[0038] In the description of the embodiments of the present disclosure, the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the embodiments of the present disclosure and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the embodiments of the present disclosure.

[0039] In the description of the embodiments of the present disclosure, unless otherwise explicitly specified and limited, the technical terms "mounting", "connecting", "connecting", "fixing" and the like should be understood broadly, for example, can be fixedly connected, or can be detachably connected, or can be integrated; can be mechanically connected, or can be electrically connected; can be directly connected, or can be indirectly connected through an intermediate medium; can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present disclosure can be understood according to the specific circumstances.

[0040] In the corresponding drawings of the embodiments of the present disclosure, in order to better understand and facilitate the description, the thickness and area of the layer are enlarged. When describing that a component (such as a layer, a film, a region or a substrate) is on or on the surface of another component, the component can be "directly" on the surface of the other component, or there can be a third component between the two components. On the contrary, when describing that a component is on the surface of another component or a component surface is formed or provided with another component, it means that there is no third component between the two components. In addition, when describing that a component is "formed" on another component, it means that the component is not formed on the entire surface (or front surface) of the other component, nor is it formed on the edge of the entire surface.

[0041] In the description of the embodiments of the present disclosure, when a certain component "includes" another component, unless otherwise stated, other components are not excluded and other components can also be further included. In addition, when a layer, film, region or plate and the like component is referred to as "on / over" another component, it can be "directly on" another component (i.e. between the surface of another component and another component without other components), or another component can exist therebetween. In addition, when a layer, film, region, plate and the like component is "directly on" another component, or when a layer, film, region, plate and the like component is on the surface of another component, it means that there is no other component therebetween.

[0042] The embodiments of the present disclosure will be described in detail below with reference to the drawings. However, those skilled in the art can understand that in the embodiments of the present disclosure, many technical details are presented in order to enable the reader to better understand the present disclosure. However, the technical solutions claimed by the present disclosure can be implemented even without these technical details and various changes and modifications based on the following embodiments.

[0043] Figure 1 A cross-sectional structure schematic diagram of a solar cell provided by an embodiment of the present disclosure, Figure 2 A top view structure schematic diagram of a solar cell provided by an embodiment of the present disclosure, Figure 3 A top view structure schematic diagram of a solar cell provided by an embodiment of the present disclosure, Figure 2 A partial enlarged schematic diagram of part A, Figure 4 Another top view structure schematic diagram of a solar cell provided by an embodiment of the present disclosure, Figure 5 A top view structure schematic diagram of a solar cell provided by an embodiment of the present disclosure, Figure 4 A partial enlarged schematic diagram of part B.

[0044] Reference is made to Figures 1 to 5 The solar cell comprises a substrate 100, a doped conductive layer 101, a first grid line 102 and a second grid line 103. The doped conductive layer 101 is located on the substrate 100; the first grid line 102 is located on the substrate 100 and in electrical contact with the doped conductive layer 101, the orthographic projection of the first grid line 102 on the substrate 100 is a wave shape or a zigzag shape with multiple inflection points, the first grid line 102 comprises multiple first segments 112 and second segments 122 which are alternately distributed, the distance D1 between adjacent inflection points in the first segment 112 along the first direction X is less than the distance D2 between adjacent inflection points in the second segment 122 along the first direction X; the second grid line 103 is located on the substrate 100, the second grid line 103 extends along the second direction Y and is connected with the first segment 112.

[0045] The solar cell is one of a PERC (Passivated Emitter Rear Cell) cell, an IBC (Interdigitated Back Contact) cell, a TOPCon (Tunnel Oxide Passivated Contact) cell, a heterojunction cell, a solar thin film cell, a stacked cell or any combination thereof. The solar thin film cell includes but is not limited to a perovskite solar thin film cell, a copper-indium-selenium solar thin film cell, a gallium arsenide solar thin film cell, and a cadmium sulfide solar thin film cell. The stacked cell includes but is not limited to a perovskite cell stacked with a crystalline silicon cell, a perovskite cell stacked with a perovskite cell, and a perovskite cell stacked with a thin film cell.

[0046] The substrate 100 is configured to receive incident light and generate photo-generated carriers. In some embodiments, the substrate 100 can be a semiconductor substrate.

[0047] In some embodiments, the material of the substrate 100 can be an elemental semiconductor material. Specifically, the elemental semiconductor material is composed of a single element, for example, can be silicon or germanium. Among them, the elemental semiconductor material can be single-crystalline, polycrystalline, amorphous or microcrystalline (a state having both single-crystalline and amorphous, referred to as microcrystalline), for example, silicon can be at least one of single-crystalline silicon, polycrystalline silicon, amorphous silicon or microcrystalline silicon.

[0048] In some embodiments, the material of the substrate 100 can also be a compound semiconductor material. Common compound semiconductor materials include, but are not limited to, silicon germanium, silicon carbide, gallium arsenide, indium gallium, perovskite, cadmium telluride, copper indium selenium and the like.

[0049] The substrate 100 can also be a sapphire substrate, a silicon-on-insulator substrate or a germanium-on-insulator substrate.

[0050] The substrate 100 can be an N-type semiconductor substrate or a P-type semiconductor substrate. The N-type semiconductor substrate is doped with an N-type doping element, which can be any one of a group V element such as phosphorus (P) element, bismuth (Bi) element, antimony (Sb) element or arsenic (As) element. The P-type semiconductor substrate is doped with a P-type element, which can be any one of a group III element such as boron (B) element, aluminum (Al) element, gallium (Ga) element or indium (In) element.

[0051] The substrate 100 has a first surface 110 and a second surface 120 opposite to each other. In some embodiments, the solar cell is a single-sided cell, and the first surface 110 of the substrate 100 can be used as a light-receiving surface to receive incident light, and the second surface 120 can be used as a back surface. In some embodiments, the solar cell is a double-sided cell, and both the first surface 110 and the second surface 120 of the substrate 100 can be used as light-receiving surfaces to receive incident light. It can be understood that the back surface referred to in the embodiments of the present application can also receive incident light, but the receiving degree of the back surface is weaker than that of the light-receiving surface, and thus the back surface is defined as the back surface.

[0052] In some embodiments, a texturing process can be performed on at least one of the first surface and the second surface of the substrate to form a textured surface on at least one of the first surface and the second surface of the substrate. In this way, the absorption and utilization of incident light by the first surface and the second surface of the substrate can be enhanced. In some embodiments, the textured surface can be a pyramid textured surface. As a common textured surface, the pyramid textured surface not only reduces the reflectivity of the substrate surface, but also forms a light trap, enhances the absorption of incident light by the substrate, and improves the photoelectric conversion efficiency of the solar cell.

[0053] The doped conductive layer 101 is doped with N-type or P-type doping elements.

[0054] The material of the doped conductive layer 101 can include at least one of amorphous silicon, polysilicon, or silicon carbide.

[0055] The first gate line 102 is a fine gate line, which is used to contact the doped conductive layer 101 and collect current.

[0056] The first gate line 102 includes a plurality of first segments 112 and second segments 122, which are artificially divided. The first segment 112 is a part of the first gate line 102 between two adjacent turning points connected to a region corresponding to the main gate (the second gate line 103), and the second segment 122 is the remaining part of the first gate line 102 except the first segment 112. The first segment 112 is used to connect the second gate line 103.

[0057] In some embodiments, the first segment 112 is a part of the first gate line 102 with the smallest distance between two adjacent turning points in the first direction X. The two adjacent turning points of the first segment 112 can be considered as two endpoints of the first segment 112.

[0058] With reference to Figure 2 , when the orthographic projection of the first gate line 102 on the substrate 100 is sawtooth-shaped, the turning points are tooth tips. With reference to Figure 4 , when the orthographic projection of the first gate line 102 on the substrate 100 is wavy, the turning points are wave crests or troughs.

[0059] In some embodiments, the material of the first gate line 102 is a copper-silver composite paste. Using the copper-silver composite paste can reduce the manufacturing cost of the first gate line 102.

[0060] The second gate line 103 is a main gate line, which is connected to the first gate line 102 and used to collect the current collected by the first gate line 102.

[0061] In some embodiments, the material of the second gate line 103 is a pure silver paste. In this way, the second gate line 103 has good conductivity, which can improve the efficiency of the second gate line 103 in collecting current, thereby improving the performance of the solar cell.

[0062] The first direction X is the arrangement direction of the plurality of second gate lines 103, and the second direction Y is the extension direction of the second gate line 103. The first direction X can be perpendicular to the second direction Y.

[0063] It can be understood that, Figure 1The doped conductive layer, the first gate line and the second gate line are shown to be located on the first surface of the substrate. In practice, the doped conductive layer, the first gate line and the second gate line can also be located on the second surface of the substrate, or the doped conductive layer, the first gate line and the second gate line are provided on both the first surface and the second surface of the substrate. In addition, for ease of illustration, Figure 2 and Figure 4 Only the case where the solar cell includes three second gate lines is shown in FIG. 1. In practice, the number of second gate lines can also be 4, 5, 6 or other positive integers.

[0064] Referring to Figures 2 to 5 In some embodiments, the distance D2 between adjacent inflection points in the second segment 122 along the first direction X gradually decreases in the direction close to the first segment 112. That is, the second segment 122 gradually increases in the area of the orthographic projection of the second segment 122 on the substrate 100 in the direction close to the second gate line 103, so that the portion of the second segment 122 close to the second gate line 103 can collect more current, thereby improving the efficiency of the solar cell in collecting current. And the portion of the second segment 122 away from the second gate line 103 can reduce its own shading area, thereby facilitating the improvement of the performance of the solar cell.

[0065] In some embodiments, the distance D1 between adjacent inflection points in the first segment 112 along the first direction X is 0.25mm~0.75mm, for example, 0.25mm~0.4mm, 0.4mm~0.6mm or 0.6mm~0.75mm. For example, the distance D1 between adjacent inflection points in the first segment 112 along the first direction X can be 0.25mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm or 0.75mm. When the distance D1 between adjacent inflection points in the first segment 112 along the first direction X is within the above range, the distance D1 between adjacent inflection points along the first direction X is small, the orthographic projection area of the first segment 112 on the substrate 100 is large, the first segment 112 can collect more current, and the first segment 112 can transmit the more current collected to the second gate line 103, thereby facilitating the improvement of the efficiency of the solar cell in collecting current, and thereby improving the performance of the solar cell.

[0066] The distance D2 between adjacent turning points in the second section 122 along the first direction X is 0.76mm-1.5mm, for example, 0.76mm-1mm, 1mm-1.25mm or 1.25mm-1.5mm. For example, the distance D2 between adjacent turning points in the second section 122 along the first direction X can be 0.76mm, 0.8mm, 1mm, 1.2mm, 1.25mm, 1.3mm or 1.5mm. When the distance D2 between adjacent turning points in the second section 122 along the first direction X is within the above range, the distance D2 between adjacent turning points in the second section 122 along the first direction X is larger, and the area of the orthographic projection of the second section 122 on the substrate 100 is smaller, which can reduce the light-shielding area of the second section 122 and help improve the performance of the solar cell.

[0067] In some embodiments, the distance between adjacent turning points in the first section along the second direction Y is equal to the distance between adjacent turning points in the second section along the second direction Y.

[0068] In some embodiments, the distance D3 between adjacent turning points along the second direction Y is 0.1mm-0.5mm, for example, 0.1mm, 0.2mm, 0.3mm, 0.4mm or 0.5mm. The distance D3 between adjacent turning points along the second direction Y is positively correlated with the area of the orthographic projection of the first grid line 102 on the substrate 100, and when the distance D3 between adjacent turning points along the second direction Y is within the above range, the area of the orthographic projection of the first grid line 102 on the substrate 100 is moderate, which can avoid the area of the orthographic projection of the first grid line 102 on the substrate 100 being too large to affect the absorption of sunlight by the substrate 100. It can also avoid the area of the orthographic projection of the first grid line 102 on the substrate 100 being too small to affect the current collection of the first grid line 102.

[0069] Figure 6 Another schematic diagram of the cross-sectional structure of the solar cell provided by the embodiments of the present disclosure, Figure 7 A schematic diagram of the top view structure of the conductive part 105 in the solar cell provided by the embodiments of the present disclosure. In the figure, Figure 6 In the figure, the first grid line and the second grid line are not shown in order to better show the groove. The conductive part is filled in the groove, so Figure 7 In the figure, the width of the conductive part along the first direction can reflect the width of the groove along the first direction, and the width of the conductive part along the second direction can reflect the width of the groove along the second direction, that is, the width of the conductive part along the first direction can be considered to be equal to the width of the groove along the first direction, and the width of the conductive part along the second direction can be considered to be equal to the width of the groove along the second direction.

[0070] Reference Figure 6 and Figure 7In some embodiments, the solar cell further comprises a passivation layer 104 and a conductive part 105, the passivation layer 104 is located on the surface of the doped conductive layer 101 facing away from the substrate 100, a recess 114 is arranged in the passivation layer 104, the first grid line 102 and the second grid line 103 are cross-connected, and the cross-connection part of the first grid line 102 and the second grid line 103 is located in the recess 114; the conductive part 105 is located in the recess 114 and is in electrical contact with the first grid line 102 and the second grid line 103 located in the recess 114.

[0071] The passivation layer 104 can passivate the substrate 100, reduce the defect state density of the first surface 110 of the substrate 100, and better inhibit the carrier recombination of the first surface 110 of the substrate 100.

[0072] The material of the passivation layer 104 can be at least one of silicon oxide, aluminum oxide, silicon nitride, or silicon oxynitride.

[0073] In some embodiments, the passivation layer 104 can be a single-layer structure. In some embodiments, the passivation layer 104 can also be a multi-layer structure, the materials of the layers in the multi-layer structure can be different from each other, or the materials of part of the number of layers can be different from each other, and the materials of the remaining part of the number of layers can be the same. For example, the passivation layer 104 can be a multi-layer structure comprising a silicon nitride layer and an aluminum oxide layer.

[0074] The recess 114 is used to accommodate the cross-connection part of the first grid line 102 and the second grid line 103, and is also used to accommodate the conductive part 105, so that the conductive part 105 can be in electrical contact with the cross-connection part of the first grid line 102 and the second grid line 103, the contact resistance of the cross-connection part of the first grid line 102 and the second grid line 103 can be reduced, the efficiency of the second grid line 103 collecting the current on the first grid line 102 can be improved, and thus the performance of the solar cell can be improved.

[0075] The material of the conductive part 105 can be metal (e.g., tungsten (W), titanium (Ti), molybdenum (Mo), niobium (Nb), vanadium (V), hafnium (Hf), tantalum (Ta), chromium (Cr), zirconium (Zr), iron (Fe), ruthenium (Ru), osmium (Os), cobalt (Co), rhodium (Rh), iridium (Ir), nickel (Ni), palladium (Pd), platinum (Pt), copper (Cu), silver (Ag), gold (Au), aluminum (Al)), alloy (e.g., Co-based alloy, Fe-based alloy, Ni-based alloy, Fe and Ni-based alloy, Co and Ni-based alloy, Fe and Co-based alloy, Co and Ni and Fe-based alloy, Al-based alloy, Cu-based alloy, magnesium (Mg)-based alloy, Ti-based alloy, steel, low-carbon steel, stainless steel), conductive metal-containing material (e.g., conductive metal nitride, conductive metal silicide, conductive metal carbide, conductive metal oxide), and conductive doped semiconductor material (e.g., conductive doped polysilicon, conductive doped germanium (Ge), conductive doped silicon germanium (SiGe)).

[0076] It can be understood that, Figure 6 and Figure 7 In FIG. 1C, the conductive part 105 is located at the bottom of the groove 114, and the intersection of the first gate line 102 and the second gate line 103 is located on the surface of the conductive part 105 away from the substrate 100. In fact, the intersection of the first gate line 102 and the second gate line 103 can also be located at the bottom of the groove 114, and the conductive part 105 can be located on the surface of the intersection of the first gate line 102 and the second gate line 103 away from the substrate 100. If the conductive part 105 is filled in the groove 114 first, and then the first gate line 102 and the second gate line 103 are printed, the conductive part 105 is located at the bottom of the groove 114, and the intersection of the first gate line 102 and the second gate line 103 is located on the surface of the conductive part 105 away from the substrate 100. If the first gate line 102 and the second gate line 103 are printed first, and then the conductive part 105 is filled in the groove 114, the intersection of the first gate line 102 and the second gate line 103 is located at the bottom of the groove 114, and the conductive part 105 is located on the surface of the intersection of the first gate line 102 and the second gate line 103 away from the substrate 100.

[0077] In some embodiments, the width W1 of the groove 114 along the first direction X is greater than the width of the second gate line 103 along the first direction X, and the width W2 of the groove 114 along the second direction Y is greater than the width of the first gate line 102 along the second direction Y. In this way, the width W1 of the groove 114 along the first direction X is greater, and the width W2 of the groove 114 along the second direction Y is greater, so that the groove 114 can accommodate more conductive parts 105, and the contact resistance of the first gate line 102 and the second gate line 103 can be further reduced, and the performance of the solar cell can be improved.

[0078] In some embodiments, the width W1 of the groove 114 along the first direction X is 0.5mm-1mm, for example, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm or 1mm. The width W1 of the groove 114 along the first direction X in the above range can accommodate an appropriate amount of the conductive part 105, effectively reducing the contact resistance of the intersection part of the first grid line 102 and the second grid line 103. It can also avoid that the width of the groove 114 along the first direction X is too large, affecting the passivation effect of the passivation layer 104.

[0079] The width W2 of the groove 114 along the second direction Y is 10μm-30μm, for example, 10μm, 15μm, 20μm, 25μm or 30μm. The width W2 of the groove 114 along the second direction Y in the above range can accommodate an appropriate amount of the conductive part 105, effectively reducing the contact resistance of the intersection part of the first grid line 102 and the second grid line 103. It can also avoid that the width of the groove 114 along the second direction Y is too large, affecting the passivation effect of the passivation layer 104.

[0080] Reference Figure 1 , Figure 2 and Figure 4 In some embodiments, the substrate 100 includes two oppositely arranged first edges 130, and the width of the second grid line 103 close to the first edge 130 along the first direction X is greater than the width of the second grid line 103 away from the first edge 130 along the first direction X. The width of the second grid line 103 close to the first edge 130 along the first direction X is greater, which can improve the current collection capability of the second grid line 103 close to the first edge 130, and improve the performance of the solar cell; the width of the second grid line 103 away from the first edge 130 along the first direction X is smaller, which can reduce the light-shielding area of the second grid line 103 away from the first edge 130 to the substrate 100, which is beneficial to improve the performance of the solar cell.

[0081] In some embodiments, the width of the second grid line 103 close to the first edge 130 along the first direction X is 1.2mm-2mm, for example, 1.2mm, 1.4mm, 1.6mm, 1.8mm or 2mm. In this way, the width of the second grid line 103 close to the first edge 130 along the first direction X is greater, which can improve the current collection capability of the second grid line 103 close to the first edge 130, and improve the performance of the solar cell.

[0082] In some embodiments, the second busbar 103 away from the first edge 130 has a width along the first direction X of 0.8mm-1.9mm, such as 0.8mm, 1mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm or 1.9mm. In this way, the second busbar 103 away from the first edge 130 has a smaller width along the first direction X, which can reduce the light-shielding area of the second busbar 103 away from the first edge 130 on the substrate 100, and thus improve the performance of the solar cell.

[0083] Figure 8 A structural schematic diagram of the second busbar 103 in the solar cell provided by the embodiments of the present disclosure.

[0084] Reference Figure 8 In some embodiments, the second busbar 103 includes a main body part 113 and edge parts 123 located at both ends of the main body part 113, and the edge parts 123 include a first end 133 close to the main body part 113 and a second end 143 away from the main body part 113. The first end 133 has a width along the first direction X equal to the width of the main body part 113 along the first direction X, the second end 143 has a width along the first direction X smaller than the width of the main body part 113 along the first direction X, and the width of the edge part 123 along the first direction X gradually increases in the direction close to the main body part 113. In this way, the average width of the edge part 123 along the first direction X is small, which can reduce the welding stress between the edge part 123 and the solder ribbon when the second busbar 103 is welded with the solder ribbon, and thus avoid the situation that the battery is cracked or damaged due to excessive welding stress between the edge part 123 and the solder ribbon.

[0085] In some embodiments, the ratio of the width of the second end 143 along the first direction X to the width of the first end 133 along the first direction X is 0.4-0.9, such as 0.4, 0.5, 0.6, 0.7, 0.8 or 0.9. The ratio of the width of the second end 143 along the first direction X to the width of the first end 133 along the first direction X is within the above range, so that the width of the second end 143 is small and the average width of the edge part 123 along the first direction X is small. This can reduce the welding stress between the edge part 123 and the solder ribbon when the second busbar 103 is welded with the solder ribbon, and thus avoid the situation that the battery is cracked or damaged due to excessive welding stress between the edge part 123 and the solder ribbon.

[0086] In some embodiments, the solar cell further includes an anti-reflection coating (not shown) on the surface of the first busbar 102 away from the substrate 100.

[0087] The anti-reflection coating can reduce the reflectivity of the surface of the first busbar 102 away from the substrate 100, and thus improve the performance of the solar cell.

[0088] The material of the anti-reflection coating is at least one of silicon oxide and titanium oxide.

[0089] Figure 9 A structural schematic diagram of a stacked battery provided by an embodiment of the present disclosure.

[0090] In combination with reference Figure 1 And Figure 9 The stacked battery includes a bottom battery 106 and a top battery 107, the bottom battery 106 is a solar cell provided by the foregoing embodiments, and the top battery 107 is located on the bottom battery 106. The top battery 107 can be located on the first surface 110 of the bottom battery 106.

[0091] In some embodiments, the top battery 107 can include a first transfer layer, a perovskite substrate 100, a second transfer layer, a transparent conductive layer, and an anti-reflection layer. The first transfer layer is located between the bottom battery 106 and the perovskite substrate 100.

[0092] In some embodiments, the first transfer layer can be one of an electron transfer layer or a hole transfer layer, and the second transfer layer can be the other of the electron transfer layer or the hole transfer layer.

[0093] Some embodiments of the present disclosure also provide a photovoltaic module, which can include the solar cell in any of the embodiments or the stacked battery in the foregoing embodiments. It should be noted that the same or corresponding parts as the foregoing embodiments can refer to the foregoing embodiments, which will not be described hereinafter.

[0094] Figure 10 A structural schematic diagram of a photovoltaic module provided by an embodiment of the present disclosure.

[0095] In combination with reference Figure 10 The photovoltaic module includes a battery string, the battery string is connected by a plurality of solar cells 20 in any of the foregoing embodiments or a plurality of stacked batteries in the foregoing embodiments. The photovoltaic module further includes an encapsulating adhesive film 21 and a cover plate 22, the encapsulating adhesive film 21 is used to cover the surface of the battery string, and the cover plate 22 is used to cover the surface of the encapsulating adhesive film 21 away from the battery string.

[0096] In some embodiments, the battery string further includes a solder strip 23, the solder strip 23 is used to electrically connect adjacent solar cells 20 or adjacent stacked batteries.

[0097] In some embodiments, the encapsulation film 21 comprises a first encapsulation layer covering one of the front side and the back side of the solar cell, and a second encapsulation layer covering the other of the front side and the back side of the solar cell. Specifically, at least one of the first encapsulation layer and the second encapsulation layer can be an organic encapsulation film such as a polyvinyl butyral (PVB) film, an ethylene-vinyl acetate (EVA) film, a polyolefin elastomer (POE) film, or a polyethylene terephthalate (PET) film, or at least one of the first encapsulation layer and the second encapsulation layer can also be an EP film, an EPE film, or a PVP film. The EP film refers to a co-extrusion film formed by stacking an EVA film and a POE film, the EPE film refers to a co-extrusion film formed by stacking an EVA film, a POE film, and an EVA film in sequence, and the PVP film refers to a co-extrusion film formed by stacking a POE film, an EVA film, and a POE film in sequence. The co-extrusion film can be prepared by extruding one or more raw materials onto another film prepared in advance in sequence during film processing, or by bonding different types of films to each other.

[0098] In some cases, the first encapsulation layer and the second encapsulation layer have a boundary before lamination, and the photovoltaic module formed after the lamination process no longer has the concept of the first encapsulation layer and the second encapsulation layer, i.e., the first encapsulation layer and the second encapsulation layer have formed an integral encapsulation film 21.

[0099] In some embodiments, the cover plate 22 can be a glass cover plate, a plastic cover plate, or the like having a light-transmitting function. Specifically, the surface of the cover plate 22 facing the encapsulation film 21 can be a concave-convex surface or a suede surface comprising a plurality of convex structures, thereby increasing the utilization rate of incident light. The cover plate 22 comprises a first cover plate opposite the first encapsulation layer and a second cover plate opposite the second encapsulation layer.

[0100] It is understood by those skilled in the art that the above embodiments are specific embodiments for implementing the present disclosure, and in actual applications, various changes can be made in form and details without departing from the spirit and scope of the present disclosure. Any person skilled in the art can make various modifications and changes without departing from the spirit and scope of the present disclosure, and therefore the protection scope of the present disclosure should be limited by the scope defined in the claims.

Claims

1. A solar cell, characterized in that: include: substrate; a doped conductive layer, wherein the doped conductive layer is located on the substrate; a first gate line, the first gate line being located on the substrate and electrically contacting the doped conductive layer, the orthographic projection of the first gate line on the substrate being a wave or sawtooth shape having a plurality of inflection points, the first gate line comprising a plurality of alternating first segments and second segments, the distance between adjacent inflection points in the first segments along a first direction being smaller than the distance between adjacent inflection points in the second segments along the first direction; A second gate line is located on the substrate, extends along a second direction, and is connected to the first segment.

2. The solar cell according to claim 1, wherein In a direction approaching the first segment, the distance between adjacent inflection points in the second segment along the first direction gradually decreases.

3. The solar cell according to claim 1, wherein The distance between adjacent inflection points in the first section along the first direction is 0.25 mm to 0.75 mm, and the distance between adjacent inflection points in the second section along the first direction is 0.76 mm to 1.5 mm.

4. The solar cell according to claim 1, wherein The distance between adjacent inflection points along the second direction is 0.1 mm to 0.5 mm.

5. The solar cell according to claim 1, wherein The solar cell further comprises: a passivation layer, the passivation layer being located on a surface of the doped conductive layer facing away from the substrate, the passivation layer being provided with a groove penetrating the passivation layer, the first gate line being cross-connected with the second gate line, and the intersection of the first gate line and the second gate line being located in the groove; A conductive portion is located in the groove and electrically contacts the first gate line and the second gate line located in the groove.

6. The solar cell according to claim 5, characterized in that The width of the groove along the first direction is greater than the width of the second gate line along the first direction, and the width of the groove along the second direction is greater than the width of the first gate line along the second direction.

7. The solar cell according to claim 1, wherein The substrate includes two oppositely disposed first edges, and a width of the second gate line close to the first edge along the first direction is greater than a width of the second gate line away from the first edge along the first direction.

8. The solar cell according to claim 1, wherein The second gate line includes a main body and edge portions located at both ends of the main body, the edge portions include a first end close to the main body and a second end away from the main body, the width of the first end along the first direction is equal to the width of the main body along the first direction, the width of the second end along the first direction is smaller than the width of the main body along the first direction, and the width of the edge portion along the first direction gradually increases in the direction close to the main body.

9. A laminated battery, characterized in that: include: A bottom cell, wherein the bottom cell is a solar cell according to any one of claims 1 to 8; A top cell is located on the bottom cell.

10. A photovoltaic module, characterized in that: include: A battery string formed by connecting a plurality of solar cells according to any one of claims 1 to 8, or a plurality of stacked batteries according to claim 9; A packaging film, the packaging film is used to cover the surface of the battery string; A cover plate is used to cover the surface of the packaging film facing away from the battery string.

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