Solar cell, cell string and photovoltaic module

Abstract

The invention provides a solar cell, a cell string and a photovoltaic module, and relates to the technical field of photovoltaics. The solar cell includes: a cell body; the electrode structure comprises a plurality of interconnection parts, and the electrode structure is electrically connected with the battery body; the surface area covered by at least one interconnection part comprises a suede area and a polished surface area; and at least one interconnection part is in direct contact with at least part of the suede area covered below the interconnection part. According to the invention, the binding force between the interconnection part and the battery body is improved, and the interconnection part and the battery body are combined more firmly and are not easy to pull off and fall off; moreover, the part, arranged in the suede area, of the interconnection part, and the surface, far away from the battery body, of the interconnection part is relatively rough, so that the contact area between the interconnection part and the interconnection piece is increased, and the binding force between the interconnection part and the interconnection piece is improved; in addition, the part, formed on the polishing surface area, of the interconnection part is good in quality, and optimal balance of the quality of the interconnection part, the binding force between the interconnection part and the battery body and the binding force between the interconnection part and the interconnection piece is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of photovoltaic, in particular to a solar cell, a cell string and a photovoltaic module. BACKGROUND

[0002] The electrode structure of the solar cell is used for collecting and conducting current. The interconnection part in the electrode structure is used for electrical connection with the interconnector, and each solar cell is electrically connected to expand the application scenario of the solar cell.

[0003] In the existing solar cell, the bonding force between the interconnection part and the cell body is weak, and during the long-term service of the solar cell, problems such as poor contact, pull-off and falling off are prone to occur, which affects the working stability and service life of the solar cell. SUMMARY

[0004] The present application provides a solar cell, a cell string and a photovoltaic module, which aims to solve the problem of weak bonding force between the interconnection part and the cell body in the existing solar cell.

[0005] In a first aspect of the present application, a solar cell is provided, comprising: a cell body; the cell body comprises intersecting first and second edges;

[0006] An electrode structure comprises: a plurality of contact electrodes and a plurality of interconnection parts, the interconnection parts are arranged on the side of the contact electrodes away from the cell body, the contact electrodes extend along the extension direction of the first edge, the interconnection parts are distributed along the extension direction of the second edge, and the electrode structure is electrically connected with the cell body; the surface area covered by at least one interconnection part comprises a textured area and a polished surface area; at least one interconnection part is in direct contact with at least part of the textured area covered thereby.

[0007] In the present application, the interconnection part is a site for welding, which can be a solder pad for example. The surface area covered by the at least one interconnection part includes a rough surface area and a polished surface area. Moreover, the at least one interconnection part is in direct contact with at least part of the rough surface area underneath it. The rough surface area is rougher than the polished surface area, and the contact area between the rough surface area and the interconnection part is larger, which improves the bonding force between the interconnection part and the battery body, and makes the combination of the two more secure and less likely to be pulled off or fall off. Moreover, the interconnection part is arranged on part of the rough surface area, and the surface of the battery body away from the interconnection part is rougher or less smooth, which increases the contact area between the interconnection part and the interconnection piece and improves the bonding force between the interconnection part and the interconnection piece. In addition, the part of the interconnection part formed on the polished surface area has good quality, which realizes the optimized balance among the quality of the interconnection part, the bonding force between the interconnection part and the battery body, and the bonding force between the interconnection part and the interconnection piece. In summary, the present application not only improves the bonding force between the interconnection part and the battery body, the bonding force between the interconnection part and the interconnection piece, the conductivity, the efficiency of the battery, but also improves the reliability and stability of the solar cell, the battery string, and the photovoltaic module during long-term service, and improves the service life.

[0008] The present application also provides a solar cell, wherein the battery body comprises a silicon substrate and a doped region arranged on the silicon substrate, and adjacent doped regions have a spacing region therebetween. At least one interconnection part covers at least part of the doped region and at least part of the spacing region. There is a height difference between at least part of the doped region and at least one adjacent spacing region.

[0009] Due to the height difference between the doped region and the adjacent spacing region, the interconnection part covers the doped region and the adjacent spacing region with the height difference, so that the interconnection part covers the height difference in the height direction, or in other words, the area covered by the interconnection part is uneven in height, rough or less smooth in the height direction, which increases the contact area between the interconnection part and the battery body and improves the bonding force between the interconnection part and the battery body, the reliability and stability of the solar cell, the battery string, and the photovoltaic module during long-term service, and the service life. Moreover, the surface of the interconnection part away from the battery body can be uneven at the position of the height difference, which also improves the bonding force between the interconnection part and the interconnection piece. The interconnection piece is a solder strip, and in the case where flux is arranged between the interconnection part and the interconnection piece, the uneven surface of the interconnection part allows the flux to stay in the area, which enhances the welding effect, and limits the flow of the flux, reducing the risk of short circuit.

[0010] In some possible embodiments, the doped region and the spacing region form a stepped surface with a certain height difference, and the sidewall of the stepped surface has a certain texture structure, such as a ridge line, a square-shaped recess, a local protruding part, etc., which further improves the roughness of the contact surface and increases the bonding effect.

[0011] In some possible embodiments, the contact electrode is arranged on the side of the doped region away from the silicon substrate, and a surface and / or a sidewall of the contact electrode form a concave-convex topography such as a stack of granules of different sizes, a ridge line, or the like, so as to further increase the contact area between the interconnection part and the contact electrode and increase the bonding force between the interconnection part and the battery body.

[0012] In some possible embodiments, the contact electrode is arranged on the side of the doped region away from the silicon substrate, and there are two height difference step surfaces between the contact electrode, the doped region, and the spacing region, so as to further increase the unevenness in the height direction and increase the bonding force between the interconnection part and the battery body.

[0013] In some possible embodiments, the plurality of interconnection parts include an edge interconnection part located at an edge region of the battery body and a middle interconnection part located at a middle region of the battery body.

[0014] In the battery body, the proportion of the area of the textured region in the surface region covered by one of the edge interconnection parts is greater than or equal to the proportion of the area of the textured region in the surface region covered by one of the middle interconnection parts.

[0015] In the edge region of the battery body, the edge interconnection part is subjected to greater tension challenges due to the thermal expansion and contraction process of the interconnection part and the solar cell or the bending and flattening process of the solar cell, and the connection reliability of the edge interconnection part and the battery body has a great influence on the connection quality of the electrode structure and the battery body and the connection quality of the electrode structure and the interconnection part. Therefore, in the edge region of the battery body, the proportion of the area of the textured region in the surface region covered by one of the edge interconnection parts is greater, so that the contact area of the edge interconnection part and the battery body in the edge region is greater, the contact effect of the two is better, and the bonding force between the two is greater. Not only is the conduction effect improved, but also the limitation of the electrical connection reliability in the edge region on the performance and service life of the photovoltaic module is avoided.

[0016] In some possible embodiments, the proportion of the area of the textured region in the surface region covered by one of the interconnection parts in the battery body is greater than or equal to 5%.

[0017] The greater the proportion of the area of the textured region in the surface region covered by one of the interconnection parts, the greater the contact area of the battery body and the interconnection part, the greater the bonding force between the interconnection part and the battery body, and the more firm the combination of the two, which are less likely to be pulled off or fall off. Moreover, the part of the interconnection part arranged in the textured region is away from the relatively rough or uneven surface of the battery body, which increases the contact area of the interconnection part and the interconnection part and improves the bonding force between the interconnection part and the interconnection part.

[0018] In some possible embodiments, the interconnecting part comprises a first end and a second end opposite to each other along the extension direction of the second edge.

[0019] In the battery body, the surface area covered by at least one of the first end and the second end of the interconnecting part is a rough surface area.

[0020] The interconnecting part is subjected to greater tension in the extension direction of the second edge, and therefore the interconnecting part comprises a first end and a second end opposite to each other along the extension direction F of the second edge, and the surface area covered by at least one of the two ends is a rough surface area, which is more conducive to ensuring the bonding force of the interconnecting part and the battery body and the interconnecting member, so as to avoid "peeling", thereby causing the interconnecting part or the interconnecting member to be separated from the battery body.

[0021] In some possible embodiments, in the battery body, the surface area covered by the interconnecting part comprises: along the extension direction of the second edge, the rough surface area and the polished surface area are alternately distributed.

[0022] The alternately distributed arrangement can effectively disperse stress and make the bonding force of the interconnecting part at each location and the battery body stronger, and the pulling force between the interconnecting part and the solar cell and the interconnecting member greater, thereby further improving the reliability of the solar cell and the photovoltaic module. In addition, the part of the interconnecting part formed on the polished surface area has good quality, and the part of the interconnecting part located on the rough surface area has a large surface area, so that the interconnecting part and the battery body and the interconnecting member are combined more firmly, and the alternately distributed arrangement is an optimized selection of the quality of the interconnecting part and the bonding quality of the interconnecting part and the battery body and the interconnecting member, which not only ensures the quality of the interconnecting part, but also ensures good bonding quality of the interconnecting part and the battery body and the interconnecting member.

[0023] In some possible embodiments, in the battery body, the surface area covered by one of the interconnecting parts comprises: along the extension direction of the second edge, the number of the rough surface area and the polished surface area is greater than or equal to 2. The quality of the interconnecting part and the bonding quality of the interconnecting part and the battery body and the interconnecting member are further optimized and balanced.

[0024] In some possible embodiments, at least a part of the surface of the interconnecting part away from the battery body is recessed toward the side of the battery body.

[0025] The shape can refract and reflect the light rays irradiated thereon multiple times, so that more light rays enter the battery body, which can improve the battery efficiency. In addition, the surface of the shape has a larger specific surface area, a larger contact area with the interconnection, and a larger bonding force therebetween. Moreover, the interconnection is a solder strip, and in the case where a flux or the like is provided between the interconnection portion and the interconnection, the flux is more likely to stay on the uneven surface, thereby enhancing the welding effect. In addition, the uneven surface limits the flow of the flux, thereby reducing the risk of short circuit.

[0026] In some possible embodiments, the doped regions include first doped regions and second doped regions that are located on the same side of the silicon substrate and are spaced apart; the first doped regions and the second doped regions are of different doping types; or,

[0027] The silicon substrate includes a first side and a second side opposite along a thickness direction thereof; the doped regions include first doped regions located on the first side of the silicon substrate and second doped regions located on the second side of the silicon substrate; the first doped regions and the second doped regions are of different doping types.

[0028] In some possible embodiments, the doped regions are located on the same side of the silicon substrate: at least one of the interconnection portions covers at least one of the first doped regions and at least one of the second doped regions.

[0029] In some possible embodiments, the first doped regions and / or the second doped regions are arranged in a polished surface region, and the surface of the spacing region is a textured surface region, which can reduce a texturing process, save a process step, and improve production efficiency. In addition, when the first doped regions and the second doped regions are both arranged in a polished surface region, the film quality of the first doped regions and the second doped regions is better, which can improve passivation effect and current collection effect.

[0030] In some possible embodiments, the contact electrodes include first contact electrodes and second contact electrodes; the first contact electrodes are arranged on the first doped regions, and the second contact electrodes are arranged on the second doped regions.

[0031] The doped regions are located on the same side of the silicon substrate: the first contact electrodes and the second contact electrodes are both non-interrupted contact electrodes.

[0032] The interconnection portion is in electrical contact with the first contact electrode covered thereby, and an insulating adhesive is arranged between the interconnection portion and the second contact electrode covered thereby; or,

[0033] The interconnection portion is in electrical contact with the second contact electrode covered thereby, and an insulating adhesive is arranged between the interconnection portion and the first contact electrode covered thereby.

[0034] The interconnecting part can be used to collect and conduct the current or carrier collected on the first contact electrode covered by the interconnecting part, or the interconnecting part can be used to collect and conduct the current or carrier collected on the second contact electrode covered by the interconnecting part, without distinguishing the N region and the P region during the process of arranging the interconnecting part, and the process is simple.

[0035] In some possible embodiments, the interconnecting part covers at least one of the first contact electrode and at least one of the second contact electrode, and the insulating glue is arranged on the surface of the interconnecting part.

[0036] The insulating glue is arranged only on the contact electrode that is not in electrical contact; or,

[0037] The insulating glue extends from the contact electrode that is not in electrical contact to at least part of the spacing region, further enhancing the insulation effect between the contact electrode that is not in electrical contact and the interconnecting part. In addition, in the case where the spacing region is a textured region, the insulating glue can better combine with the textured region, thereby increasing the bonding force and reducing the pull-out caused by poor bonding. Moreover, the larger area of the insulating glue can better ensure the process window during the production process and reduce the short circuit or leakage caused by misalignment.

[0038] In some possible embodiments, the interconnecting part covers at least one of the first contact electrode and at least one of the second contact electrode, and the insulating glue is arranged on the surface of the interconnecting part.

[0039] The height of the part of the interconnecting part located in the first doped region, the height of the part of the interconnecting part located in the second doped region, and the height of the part of the interconnecting part corresponding to the textured region covered by the interconnecting part decrease in turn.

[0040] The surface of the interconnecting part away from the surface of the battery body is the surface on which the interconnecting part and the interconnecting member are electrically connected subsequently. The surface has at least the above three heights, and the surface is more uneven. The light rays radiated on the surface are refracted and reflected multiple times, so that more light rays enter the battery body, which can improve the battery efficiency. The surface has a larger surface area. On the one hand, the contact area with the interconnecting member is larger, the electrical connection effect between the interconnecting part and the interconnecting member is better, and the pulling force between the interconnecting part and the interconnecting member is larger, so that the interconnecting part and the interconnecting member are less likely to slip off and the like. On the other hand, the interconnecting member is a solder strip, and in the case where flux and the like are arranged between the interconnecting part and the interconnecting member, the above uneven surface can make the flux stay better, thereby enhancing the welding effect. Moreover, the above uneven surface limits the flow of the flux, thereby reducing the risk of short circuit.

[0041] In some possible embodiments, at least one of the interconnecting parts covers at least two contact electrodes of the same polarity. The interconnecting part can be electrically connected with the at least two contact electrodes of the same polarity at the same time to collect the current or carrier.

[0042] In some possible embodiments, at least one of the interconnecting portions covers 3 of the doped regions and 2 to 4 of the interval regions. Generally, the surface morphology of the doped regions and the interval regions can be different, and the same interconnecting portion covers both the doped regions and the interval regions, thereby conveniently realizing the simultaneous covering of the textured region and the polished surface region.

[0043] In some possible embodiments, the battery body comprises: a silicon substrate, a doped region, and an interface passivation layer between the silicon substrate and the doped region; and / or,

[0044] The doped region comprises at least one of doped microcrystalline silicon, doped amorphous silicon, and doped polycrystalline silicon; and / or,

[0045] The polished surface region has a textured structure; and / or,

[0046] The flatness of the polished surface region is less than that of the textured region; and / or,

[0047] The surface reflectivity of the polished surface region is greater than that of the textured region; and / or,

[0048] The material of the interconnecting portion comprises a base metal; and / or,

[0049] Along the extension direction of the second side, adjacent interconnecting portions are connected by a conductive portion.

[0050] In some possible embodiments, the battery body further comprises: a surface passivation layer arranged on the side of the doped region away from the silicon substrate;

[0051] The interconnecting portion is in direct contact with at least part of the textured region of the silicon substrate; and / or,

[0052] The interconnecting portion is in direct contact with at least part of the textured region of the doped region; and / or,

[0053] The interconnecting portion is in direct contact with at least part of the textured region of the interface passivation layer; and / or,

[0054] The interconnecting portion is in direct contact with at least part of the textured region of the surface passivation layer.

[0055] The interconnecting portion is in direct contact with at least part of the textured region of the structure having a certain hardness, and the bonding force between the two is greater.

[0056] In the second aspect, the application provides a battery string, comprising: an interconnecting member, and a plurality of any of the preceding solar cells.

[0057] The interconnecting piece is electrically connected with the interconnecting part of the solar cell; the cell body comprises: intersecting first and second edges; the interconnecting piece is arranged along the extension direction of the second edge.

[0058] In a third aspect of the present application, a photovoltaic device is provided, wherein a plurality of the above-mentioned cells are connected in series and / or in parallel along the extension direction of the interconnecting piece.

[0059] The above-mentioned solar cell, cell string and photovoltaic module have the same or similar beneficial effects, and thus will not be described here again in order to avoid repetition. BRIEF DESCRIPTION OF DRAWINGS

[0060] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the description of the embodiments of the present application will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without any creative labor on the basis of these drawings.

[0061] Figures 1 to 7 The partial cross-sectional structure schematic diagrams of seven kinds of solar cells in the embodiments of the present application are shown;

[0062] Figure 8 The bottom structure schematic diagrams of the solar cells in the embodiments of the present application are shown;

[0063] Figure 9 And Figure 10 The partial microscope schematic diagrams of two kinds of solar cells in the embodiments of the present application are shown;

[0064] Figure 11 And Figure 12 The top or bottom structure schematic diagrams of two kinds of solar cells in the embodiments of the present application are shown.

[0065] Explanation of figure numbers:

[0066] 1-interconnecting part, 11-edge interconnecting part, 12-middle interconnecting part, 2-silicon substrate, 3-first doped region, 4-second doped region, 5-interface passivation layer, 6-first contact electrode, 7-second contact electrode, 8-surface passivation and anti-reflection layer, 9-cell body, 91-first edge, 92-second edge, 93-textured region, 94-polished surface region, 10-insulating adhesive, 13-conductive part, 14-contact electrode. DETAILED DESCRIPTION

[0067] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the scope of the present application.

[0068] In the existing solar cell, the binding force of the interconnection part with the cell body is weak, and in the long-term service process of the solar cell, the main reasons for the problems of poor contact, pull-off and falling-off are as follows: the surface area covered by the interconnection part is a relatively flat polishing surface area, the contact area of the interconnection part with the relatively flat polishing surface area is small, the binding force between the interconnection part and the cell body is small, the combination of the two is not firm enough, and the two are prone to falling-off; in addition, since the interconnection part contacts the polishing surface area, the surface of the interconnection part away from the cell body is relatively flat, which leads to that the combination between the interconnection part and the interconnection piece is not firm enough, and the two are prone to pull-off. In view of the above technical problems, one technical concept of the present application is to adjust the setting of the interconnection part, so as to ensure that the surface area covered by at least one interconnection part includes a rough surface area and a polishing surface area, and at least one interconnection part directly contacts at least part of the rough surface area covered thereby. The rough surface area is relatively rough or more uneven than the polishing surface area, the contact area of the rough surface area and the interconnection part is large, the binding force between the interconnection part and the cell body is improved, the combination of the two is more firm, and the two are not prone to pull-off and falling-off; in addition, the surface of the part of the interconnection part away from the cell body is relatively rough or more uneven, which increases the contact area of the interconnection part and the interconnection piece and improves the binding force between the interconnection part and the interconnection piece; in addition, the part of the interconnection part formed on the polishing surface area has good quality, which realizes the optimized balance of the quality of the interconnection part, the binding force between the interconnection part and the cell body, and the binding force between the interconnection part and the interconnection piece.

[0069] The present application provides a solar cell, referring to Figures 1 to 8 The solar cell includes a cell body and an electrode structure. The cell body contains a PN junction, which can separate and transport carriers. The cell body includes intersecting first and second edges 91 and 92. The angle between the first and second edges 91 and 92 is not limited, for example, the two edges can be perpendicular to each other, or close to perpendicular to each other, etc. The electrode structure is used to electrically connect with the cell body, to transport and export current. The specific structure of the cell body is not limited.

[0070] Referring to Figure 11 and Figure 12The electrode structure includes a plurality of contact electrodes 14 and a plurality of interconnections 1, and the number of the contact electrodes and the number of the interconnections 1 in the electrode structure are not limited. The contact electrodes are used to collect carriers or current in the battery body and transmit the carriers or current to the interconnections. Referring to Figure 8 , Figure 11 and Figure 12 , the contact electrodes extend along the extension direction of the first side 91, and the interconnections 1 are spaced along the extension direction of the second side 92. Here, the spacing specifically refers to that there is a spacing between adjacent interconnections 1 along the extension direction of the second side 92. In some possible embodiments, referring to Figure 11 and Figure 12 , the adjacent interconnections 1 spaced along the extension direction of the second side 92 are connected by a conductive part 13, which can compensate for the local virtual welding of the interconnections 1, and the conductive part 13 connected thereto can still realize current collection and conduction, which can enhance the current conduction effect. Figure 11 and Figure 12 The difference is only in the line width of the conductive part 13, Figure 11 The line width of the conductive part 13 is larger, and the current collection and conduction effect is better. The material of the conductive part 13 can be the same as that of the contact electrode 14, or the material of the conductive part 13 can be the same as that of the interconnection 1, or the materials of the conductive part 13, the contact electrode 14 and the interconnection 1 are the same, which is not limited. For example, Figure 11 and Figure 12 The interconnection 1 shown in the electrode structure can be applied to a double-sided solar cell with electrode structures on both sides of the battery. Each interconnection 1 electrically connected by the conductive part 13 covers the same type of contact electrode, and the interconnection 1 and the contact electrode covered thereby can not be provided with an insulating adhesive, which can simplify the process. For example, each interconnection 1 electrically connected by the conductive part 13 covers the first contact electrode, or each interconnection 1 electrically connected by the conductive part 13 covers the second contact electrode.

[0071] The interconnection 1 is arranged on the side of the contact electrode away from the battery body, the contact electrode is electrically connected with the interconnection 1, and the interconnection 1 is used to be electrically connected with an interconnection member and electrically connected with other solar cells. In this application, the interconnection 1 can be a solder pad, and the like, which is not limited. The interconnection member can be a solder strip, a conductive interconnection member, and the like.

[0072] In the electrode structure of the solar cell, the surface area covered by the at least one interconnection part 1 comprises a textured area and a polished area, and the at least one interconnection part is in direct contact with at least part of the textured area covered thereby. The surface area covered by the at least one interconnection part comprises a textured area and a polished area, and the at least one interconnection part is in direct contact with at least part of the textured area covered thereby. The textured area is relatively rough compared to the polished area, and the contact area between the textured area and the interconnection part is relatively large, thereby improving the bonding force between the interconnection part and the cell body, and the two are more firmly combined and are less likely to be pulled off or fall off. Moreover, the interconnection part is arranged in the part of the textured area, and the surface of the cell body away from the interconnection part is relatively rough or relatively uneven, thereby increasing the contact area between the interconnection part and the interconnection member and improving the bonding force therebetween. In addition, the part of the interconnection part 1 formed on the polished area has good quality, thereby achieving an optimized balance among the quality of the interconnection part 1, the bonding force between the interconnection part and the cell body, and the bonding force between the interconnection part and the interconnection member. In summary, the present application not only improves the bonding force between the interconnection part and the cell body, the bonding force between the interconnection part and the interconnection member, the conductive effect, the cell efficiency, the reliability and stability during long-term service of the solar cell, the cell string, and the photovoltaic module, but also improves the service life.

[0073] It should be noted that, in the electrode structure of the solar cell, the surface area covered by one interconnection part 1 can comprise a textured area and a polished area, or the surface area covered by a plurality of interconnection parts 1 can comprise a textured area and a polished area, and one interconnection part 1 is in direct contact with at least part of the textured area covered thereby, or a plurality of interconnection parts are in direct contact with at least part of the textured area covered thereby. Here, the plurality refers to two or more. For example, in the electrode structure of the solar cell, the surface area covered by all interconnection parts 1 can comprise a textured area and a polished area, and all interconnection parts are in direct contact with at least part of the textured area covered thereby.

[0074] Here, the direct contact between the interconnection part and at least part of the textured area covered thereby refers to the direct contact between the interconnection part and at least part of the textured area of the cell body covered thereby, or the direct contact between the interconnection part and all of the textured area of the cell body covered thereby.

[0075] In some possible embodiments, the polishing surface area has a texture structure, and the shape of the texture structure can include a ridge line or the like, for example, a regular or irregular shaped texture structure composed of at least one straight ridge line and / or at least one curved ridge line. The texture structure usually has a concave-convex change at the ridge line. For example, the texture structure can include one or more tower base structures, or can include one or more partial tower base structures. In determining the above texture structure, it can be directly determined whether the part of the battery body covered by the interconnection part 1 contains the above texture structure.

[0076] In some possible embodiments, the flatness of the polishing surface is less than the flatness of the textured surface area, the textured surface area is more uneven, the contact area between the textured surface area and the interconnection part is larger, the bonding force between the interconnection part and the battery body is improved, and the two are more firmly combined and are not easy to be pulled off or fall off; and moreover, the interconnection part is arranged on the textured surface area, the surface of the battery body is rough or relatively uneven, the contact area between the interconnection part and the interconnection piece is increased, and the bonding force between the interconnection part and the interconnection piece is improved. The flatness can refer to the degree of deviation of the surface area from an ideal plane, and the determination manner of the flatness is not specifically limited in the application.

[0077] For example, the flatness of the polishing surface area is less than or equal to 2.5 um, and the flatness of the textured surface area is greater than or equal to 3 um.

[0078] In some possible embodiments, the surface reflectivity of the polishing surface is greater than the surface reflectivity of the textured surface area, the textured surface area has a better light trapping effect, and the battery efficiency is further improved. For example, Figure 9 and Figure 10 are two local microscope images or naked eye observation images of a solar cell, Figure 9 and Figure 10 In the above, the surface reflectivity of the textured surface area 93 is very small, the light trapping effect is better, and therefore the textured surface area 93 appears black or substantially black.

[0079] In some possible embodiments, the battery body comprises a silicon substrate 2, a doped region and an interface passivation layer 5 between the silicon substrate and the doped region. The silicon substrate 2 can be N-type monocrystalline silicon or P-type monocrystalline silicon, which can provide long-life carriers. The doped region can be a P-type doped region or an N-type doped region. The P-type doped region can contain one or more elements of Group IIIA (for example, it can be boron). The N-type doped region can contain one or more elements of Group VA (for example, it can be phosphorus). The materials of the N-type doped region and the P-type doped region can include any one of semiconductor materials such as silicon, silicon-germanium, germanium or gallium arsenide. In terms of the arrangement of the materials, the crystal phase of the doped region can be amorphous, microcrystalline, nanocrystalline, single crystal or polycrystalline, i.e. the doped region can include at least one of doped microcrystalline silicon, doped amorphous silicon, doped polycrystalline silicon. The materials of the N-type doped region and the P-type doped region can be the same or different. For example, the materials of the N-type doped region and the P-type doped region can both include doped polycrystalline silicon. For another example, the material of the P-type doped region can include doped polycrystalline silicon, and the material of the N-type doped region can include at least one of doped amorphous silicon, doped microcrystalline silicon and doped nanocrystalline silicon. The P-type doped region can be obtained by in-situ doping on the surface of the silicon substrate or deposition on the surface of the silicon substrate. The N-type doped region can also be obtained by in-situ doping on the surface of the silicon substrate or deposition on the surface of the silicon substrate. For example, on the front surface of the silicon substrate 2, the doped region can be provided on the silicon substrate by in-situ doping. For another example, on the back surface of the silicon substrate 2, the doped region can be obtained by deposition on the surface of the silicon substrate (for example, a tunneling oxygen layer and a doped region are deposited on the silicon substrate, and the doped region is an epitaxial doped region). The thickness of the doped region is not limited, which can be 50 nm to 500 nm. For another example, the thickness of the N-type doped region can be 50 nm to 300 nm, and the thickness of the P-type doped region can be 70 nm to 500 nm.

[0080] The silicon substrate 2 includes two surfaces opposite along the thickness direction E of the silicon substrate 2, one of the two surfaces is a front surface and the other is a back surface. As shown in FIG. 1, Figures 1 to 7 The front surface of the silicon substrate 2 is the front surface of the solar cell, and the back surface of the silicon substrate 2 is the back surface of the solar cell. The front surface of the solar cell is mainly used to receive light during the working process of the solar cell.

[0081] The material of the interface passivation layer 5 can be at least one of tunneling oxygen, intrinsic amorphous silicon, silicon carbide, silicon nitride, aluminum oxide, etc., which can provide good passivation contact performance, and the specific material of the interface passivation layer 5 is not limited.

[0082] In some possible embodiments, the battery body further comprises a surface passivation layer 8 disposed on the doped region, the surface passivation layer 8 providing surface passivation. The surface passivation layer 8 here can also provide antireflection, or in other words, the surface passivation layer can be a surface passivation and antireflection layer, without limitation on the specific material thereof, for example, can be at least one of silicon nitride, silicon oxide, silicon oxynitride, aluminum oxide, silicon carbide, amorphous silicon, etc.

[0083] In some possible embodiments, the interconnecting part 1 is in direct contact with at least part of the textured region of the silicon substrate. The silicon substrate has a relatively high hardness, and the interconnecting part 1 and the at least part of the textured region of the silicon substrate are in direct contact with a greater bonding force therebetween.

[0084] In some possible embodiments, the interconnecting part 1 is in direct contact with at least part of the textured region of the doped region. The doped region has a relatively high hardness, and the interconnecting part 1 and the at least part of the textured region of the doped region are in direct contact with a greater bonding force therebetween.

[0085] In some possible embodiments, the interconnecting part 1 is in direct contact with at least part of the textured region of the interface passivation layer 5. The interface passivation layer 5 has a relatively high hardness, and the interconnecting part 1 and the at least part of the textured region of the interface passivation layer 5 are in direct contact with a greater bonding force therebetween.

[0086] In some possible embodiments, with reference to Figures 1 to 7 , the interconnecting part 1 is in direct contact with at least part of the textured region of the surface passivation layer 8. The surface passivation layer 8 has a relatively high hardness, and the interconnecting part 1 and the at least part of the textured region of the surface passivation layer 8 are in direct contact with a greater bonding force therebetween.

[0087] In some possible embodiments, with reference to Figure 8The plurality of interconnections 1 in the solar cell can include an edge interconnection 11 located at an edge region of the cell body 9 and a middle interconnection 12 located at a middle region of the cell body 9. In the cell body 9, the proportion of the area of the textured region in the surface area covered by one edge interconnection 11 is greater than or equal to the proportion of the area of the textured region in the surface area covered by one middle interconnection 12. Specifically, in the edge region of the cell body 9, due to the thermal expansion and contraction process of the interconnection, the solar cell, or the bending and flattening process of the solar cell, the edge interconnection 11 is subjected to greater tensile force challenges, that is, the connection reliability of the edge interconnection 11 and the cell body 9 greatly affects the connection quality of the electrode structure and the cell body 9 and the electrode structure and the interconnection. Therefore, in the edge region of the cell body 9, the proportion of the area of the textured region in the surface area covered by one edge interconnection 11 is greater, so that the contact area of the edge interconnection 11 and the cell body 9 in the edge region is greater, the contact effect of the two is better, and the bonding force between the two is greater. Not only does it improve the conduction effect, but it also avoids the limitation of the edge region electrical connection reliability on the performance and service life of the photovoltaic module.

[0088] It should be noted that in this application, the proportion of the area of the textured region in the surface area covered by one edge interconnection 11 in the cell body 9 can refer to the area of the projection of the textured region in the surface area covered by the edge interconnection 11 on the surface of the cell body 9, divided by the area of the projection of the edge interconnection 11 on the surface of the cell body 9, when the edge interconnection 11 is irradiated by light along the thickness direction E of the solar cell. It can also be the average of the proportions of the areas of the textured regions in the surface areas covered by a plurality of edge interconnections 11, where the plurality refers to 2 or more. In this application, the determination method of the proportion of the area of the textured region in the surface area covered by the interconnection mentioned in other positions is the same as or similar to this, and will not be repeated here. In the cell body 9, the proportion of the area of the textured region in the surface area covered by one edge interconnection 11 is greater than or equal to the proportion of the area of the textured region in the surface area covered by one middle interconnection 12. The difference between the two area proportions is not limited in size.

[0089] In some possible embodiments, in the battery body 9, in the surface area covered by an edge interconnection 11 adjacent to the edge line, the area of ​​the velvet area accounts for greater than or equal to 10%. The edge line here refers to the first edge 91 and / or the second edge 92. Specifically, the closer to the edge line of the battery body 9, the greater the connection reliability of the edge interconnection 11 and the battery body 9, and the greater the impact on the connection quality between the electrode structure and the battery body 9, and the electrode structure and the interconnection part. Therefore, in the surface area covered by an edge interconnection 11 adjacent to the edge line, the area of ​​the velvet area accounts for greater than or equal to 10%, so that the edge interconnection 11 in the edge area near the edge line has a larger contact area with the battery body 9, the contact effect between the two is better, and the bonding force between the two is greater, which not only improves the conductive effect, but also avoids the limitation of the electrical connection reliability in the area adjacent to the edge line on the performance and life of the photovoltaic module.

[0090] For example, in the battery body 9, in the surface area covered by an edge interconnection portion 11 adjacent to the edge line, the area proportion of the suede area can be 10%, 11%, 12%, 13%, 13.5%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, or 21%.

[0091] In some possible embodiments, the battery body 9 includes: a first side 91 and a second side 92 intersecting each other; within the battery body 9, the surface area covered by an edge interconnection portion 11 adjacent to the first side 91 includes a velvet area that is greater than or equal to the surface area covered by an edge interconnection portion 11 adjacent to the second side 92 of the battery body 9. The extension direction of the second side 92 is the same as the extension direction of the interconnection member. The extension direction of the interconnection member mentioned in this application refers to its overall direction; local portions of the interconnection member are allowed to bend in other directions, and the extension direction of the second side 92 is similar to this. An edge interconnection portion 11 adjacent to the first side 91 is the outermost interconnection portion along the extension direction of the interconnection member. The outermost interconnection portion along the extension direction of the interconnection member is easier to pull off from the interconnection member, or in other words, the connection reliability between the outermost interconnection portion along the extension direction of the interconnection member and the battery body 9 has a greater impact on the connection quality between the electrode structure and the battery body 9, and the electrode structure and the interconnection member. Therefore, in the surface area covered by an edge interconnection portion 11 adjacent to the first side 91, the area of ​​the velvet area accounts for a larger proportion, so that the outermost interconnection portion along the extension direction of the interconnection member has a larger contact area with the battery body 9, the contact effect between the two is better, and the bonding force between the two is greater, which not only improves the conductive effect, but also avoids the limitation of the electrical connection reliability of the adjacent edge area on the performance and life of the photovoltaic module.

[0092] In some possible embodiments, the proportion of the area of the napped area to the total area of the surface region covered by the interconnecting part 11 adjacent to one edge of the first edge 91 in the battery body 9 is greater than or equal to 15%. As mentioned above, the proportion of the area of the napped area to the total area of the surface region covered by the interconnecting part 11 adjacent to one edge of the first edge 91 is greater, so that the contact area between the outermost interconnecting part in the extending direction of the interconnecting part and the battery body 9 is greater, the contact effect between the two is better, and the binding force between the two is greater, which not only improves the conductive effect but also avoids the limitation of the reliability of electrical connection in the area adjacent to the edge line on the performance and service life of the photovoltaic module.

[0093] For example, the proportion of the area of the napped area to the total area of the surface region covered by the interconnecting part 11 adjacent to one edge of the first edge 91 in the battery body 9 can be 15%, 16%, 17%, 18%, 19%, 19.5%, 20%, 21%, 22%, 23%, 24%, 25%, 26%.

[0094] In some possible embodiments, the proportion of the area of the napped area to the total area of the surface region covered by one interconnecting part 1 in the battery body 9 is greater than or equal to 5%. If the proportion of the area of the napped area to the total area of the surface region covered by one interconnecting part 1 is greater, the contact area between the battery body and the interconnecting part is greater, the binding force between the interconnecting part and the battery body is improved, and the two are more firmly combined and are not easy to be pulled off or fall off. Moreover, the interconnecting part is arranged in the part of the napped area, the surface of the battery body away from the interconnecting part is rough or less flat, the contact area between the interconnecting part and the interconnecting part is increased, and the binding force between the interconnecting part and the interconnecting part is improved.

[0095] For example, the proportion of the area of the napped area to the total area of the surface region covered by one interconnecting part 1 in the battery body 9 can be 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%.

[0096] Referring to Figure 8 , the battery body 9 includes a first edge 91 and a second edge 92 intersecting. Referring to Figure 9 and Figure 10 , the interconnecting part 1 includes a first end and a second end opposite in the extending direction F of the second edge 92 (the part in the red dashed line frame in Figure 9 and Figure 10 ). In some possible embodiments, referring to Figure 9 , the surface regions covered by the first end and the second end of the interconnecting part 1 in the battery body 9 are both polished surface regions 94, which can appropriately improve the quality of the interconnecting part 1. Figure 9 In some possible embodiments, referring to

[0097] In some possible embodiments, referring to Figure 10, the surface area covered by at least one of the first end and the second end of the interconnecting part 1 in the battery body 9 is the suede area 93. Here, the extension direction F of the second edge 92 is the same as the extension direction of the interconnecting part, so the pulling force in the extension direction F of the second edge 92 is greater, and therefore the interconnecting part 1 includes: the first end and the second end opposite to each other in the extension direction F of the second edge 92, and the surface area covered by at least one of the two ends is the suede area 93, which is more conducive to ensuring the bonding force of the interconnecting part 1 and the battery body and the interconnecting part, so as to prevent "peeling", thereby causing the interconnecting part 1 or the interconnecting part to separate from the battery body 9.

[0098] It should be noted that the surface area covered by only one of the first end and the second end of the interconnecting part 1 can be the suede area 93, or refer to Figure 10 , the interconnecting part 1 includes: the first end and the second end opposite to each other in the extension direction F of the second edge 92, and the surface area covered by at least one of the two ends is the suede area 93. In the interconnecting part 1, the first end and the second end opposite to each other in the extension direction F of the second edge 92, wherein in the extension direction F of the second edge 92: the length of the first end accounts for less than or equal to 10% of the length of the interconnecting part 1, and the length of the second end also accounts for less than or equal to 10% of the length of the interconnecting part 1.

[0099] In some possible embodiments, refer to Figure 8 , the battery body 9 includes: the first edge 91 and the second edge 92 intersecting. Refer to Figure 9 and Figure 10 , in the battery body 9, the surface area covered by the interconnecting part 1: along the extension direction F of the second edge, the suede area 93 and the polished surface area 94 are alternately distributed. That is, in the battery body 9, the surface area covered by the interconnecting part 1: along the extension direction F of the second edge, one suede area 93, followed by one polished surface area 94, and then one suede area 93, and the suede area 93 and the polished surface area 94 are alternately distributed, which can effectively disperse stress and make the bonding force of the interconnecting part 1 everywhere with the battery body 9 stronger, the pulling force between the interconnecting part 1 and the solar cell and the interconnecting part greater, and the reliability of the solar cell and the photovoltaic module further improved; in addition, the part of the interconnecting part 1 formed on the polished surface area 94 has good quality, and the part of the interconnecting part 1 located on the suede area 93 has a large surface area, so that the interconnecting part 1 is combined with the battery body and the interconnecting part more firmly, and the alternately distributed two are the optimized selection of the quality of the interconnecting part 1 and the bonding quality of the interconnecting part 1 with the battery body and the interconnecting part. It not only ensures the quality of the interconnecting part 1, but also ensures good bonding quality with the battery body and the interconnecting part; in addition, it has good compatibility with the current texturing process.

[0100] In some possible embodiments, refer to Figure 9 and Figure 10In the battery body 9, in the surface area covered by an interconnection part 1: along the extension direction F of the second edge 92, the number of suede areas 93 and polished surface areas 94 are both greater than or equal to 2, achieving a further optimized balance in the quality of the interconnection part 1 and the bonding quality of the interconnection part 1 with the battery body and the interconnection parts.

[0101] For example, Figure 10 In the embodiment, in the battery body 9, in the surface area covered by one interconnection 1, along the extension direction F of the second side 92, the number of suede areas 93 is 4, and the number of polished surface areas 94 is 3. For another example, in the battery body 9, in the surface area covered by one interconnection 1, along the extension direction F of the second side 92, the number of suede areas 93 can be 2, 3, 4, 5, 6, or 7, and the number of polished surface areas 94 can be 2, 3, 4, 5, or 6.

[0102] It should be noted that, referring to Figure 10 In the battery body 9, within the surface area covered by one interconnection 1, along the extension direction F of the second edge 92, the number of suede areas 93 can be greater than or equal to the number of polished surface areas 94. The greater number of suede areas 93 further enhances the bonding strength between the interconnection and the battery body, and between the interconnection and the interconnecting member, and further disperses stress. The difference between the two numbers is not limited.

[0103] In some possible embodiments, reference Figure 9 and Figure 10 At least one interconnect 1 covers at least two contact electrodes 14 of the same polarity, and the interconnect can be electrically connected to the at least two contact electrodes of the same polarity to collect current or carriers. This method can be applied to both back-contact solar cells and bifacial solar cells.

[0104] In some possible embodiments, reference Figure 9 and Figure 10 At least one interconnect 1 covers three doped regions and two to four spacer regions. Typically, the surface morphologies of the doped and spacer regions may differ. The same interconnect 1 covers both the doped and spacer regions, thereby conveniently covering both the velvet and polished regions. This approach can be applied to both back-contact solar cells and bifacial solar cells.

[0105] For example, Figure 9 and Figure 10 In the case of Figure 9 and 10 In the example, the spacing region is the velvet region 93, and the doping region ( Figure 9 and Figure 10The surface morphology of the blue surface is polished, so Figure 9 and Figure 10 In the embodiment, the doped region is the polished surface region 94 . Figure 9 and Figure 10 The interconnection 1 shown in FIG covers three doping regions. The interconnection 1 includes: a first end and a second end opposite to each other along the extension direction F of the second side. Figures 1 to 4 In the battery body, if the surface areas covered by the first and second ends of the interconnection 1 are both polished areas, then the interconnection 1 covers two spaced areas. In the battery body, if only one of the first and second ends of the interconnection 1 covers a velvet area, then the interconnection 1 covers three spaced areas. Figure 6 In the battery body, the surface areas covered by the first end and the second end of the interconnection portion 1 are both velvet areas, and the interconnection portion 1 covers four spaced areas.

[0106] In some possible embodiments, reference Figures 1 to 7 ,as well as Figures 1 to 7 , at least a portion of the surface of the interconnection part 1 away from the battery body is concave toward the battery body, and the specific location of the concave is not limited. For example, the portion of at least a portion of the surface of the interconnection part 1 away from the battery body, corresponding to the velvet area covered by it, is concave toward the battery body. This shape can refract and reflect the light irradiated thereon multiple times, so that more light enters the battery body, which can improve the battery efficiency; in addition, the specific surface area of ​​this shape is larger, the contact area with the interconnection part is larger, and the bonding force between the two is greater; moreover, when the interconnection part is a welding strip, and flux is provided between the interconnection part 1 and the interconnection part, the above-mentioned uneven surface makes it easier for the flux to stay, thereby enhancing the welding effect, and the above-mentioned uneven surface restricts the flow of the flux, reducing the risk of short circuit. The specific degree of concave is not limited here.

[0107] In some possible embodiments, the battery body includes: a silicon substrate 2 and a doping region provided on the silicon substrate 2. Since the doping region is divided into a P-type doping region and an N-type doping region, the first doping region 3 and the second doping region 4 are divided, and here, one of the first doping region 4 and the second doping region 4 is a P-type doping region and the other is an N-type doping region. For example, the first doping region may be a P-type doping region, the first doping region may be a P-type doping region, the second doping region may be an N-type doping region, and the second doping region may be an N-type doping region; or, the first doping region may be an N-type doping region, the first doping region may be an N-type doping region, the second doping region may be a P-type doping region, and the second doping region may be a P-type doping region, and there is no limitation on this. Reference Figures 1 to 7The at least one interconnection part 1 covers at least part of the doped region and at least part of the spacing region. Specifically, the surface morphology of the spacing region and the region below the doped region can be different. The at least one interconnection part 1 covers at least part of the doped region and at least part of the spacing region. The at least one interconnection part 1 covers at least part of the doped region, so that the doped region can collect the carriers or current in the area covered by the at least one interconnection part 1 to the maximum extent. At the same time, the at least one interconnection part 1 is easy to cover at least part of the textured region and at least part of the polished region. In addition, the spacing region on the front surface of the silicon substrate can transmit light, and the spacing region on the back surface of the silicon substrate can also avoid short circuit of the solar cell.

[0108] In some possible embodiments, referring to Figures 4 to 7 The height difference between the part of the doped region and the adjacent spacing region is not limited as to who is higher and who is lower. Here, the height difference refers to that, in the thickness direction of the silicon substrate, the profile line of the spacing region away from the center of the silicon substrate is not flush with the surface of the doped region away from the silicon substrate. For example, Figures 1 to 3 In the above example, on the same side of the silicon substrate 2, the doped region is higher than the spacing region. Due to the height difference between the doped region and the adjacent spacing region, the interconnection part covers the doped region and the adjacent spacing region with the height difference. Therefore, in the height direction, the interconnection part covers the height difference, that is, in the height direction, the area covered by the interconnection part is uneven in height, the area covered by the interconnection part is relatively rough or relatively uneven, the contact area between the interconnection part and the solar cell body is increased, the bonding force between the interconnection part and the solar cell body is improved, the reliability and stability of the solar cell, the solar cell string and the photovoltaic module during long-term service are improved, and the service life is also improved. Moreover, the surface of the interconnection part away from the solar cell body can be uneven at the position of the height difference, which also improves the bonding force between the interconnection part and the interconnection piece. Moreover, the interconnection piece is a solder strip, and in the case that flux is arranged between the interconnection part and the interconnection piece, the flux is more likely to stay in the area with the uneven surface, the soldering effect is enhanced, and the flow of the flux is limited by the uneven surface, thereby reducing the risk of short circuit.

[0109] In some possible embodiments, the height difference between the doped region and the adjacent spacing region can be mainly used to improve the bonding force between the interconnection part and the solar cell body, and to improve the bonding force between the interconnection part and the interconnection piece, so as to improve the reliability and stability of the solar cell, the solar cell string and the photovoltaic module during long-term service, and to improve the service life.

[0110] In some possible embodiments, the surface area covered by the interconnection part mainly includes a textured area and a polished area, so as to improve the bonding force between the interconnection part and the battery body and the bonding force between the interconnection part and the interconnection piece, thereby improving the reliability and stability of the solar cell, the battery string and the photovoltaic module during long-term service, and improving the service life.

[0111] In some possible embodiments, the surface area covered by the interconnection part mainly includes a textured area and a polished area, so as to improve the bonding force between the interconnection part and the battery body and the bonding force between the interconnection part and the interconnection piece, thereby improving the reliability and stability of the solar cell, the battery string and the photovoltaic module during long-term service, and improving the service life.

[0112] In the present application, the width of the doped area is not limited. For example, the width of the P-type doped area is 100 μm to 2000 μm, and the width of the N-type doped area is 100 μm to 2000 μm. For another example, the width of the interval area is 50 nm to 3000 nm. The width of the interconnection part 1 can be 0.5 mm to 5 mm, and the length can be 0.1 mm to 210 mm. The length of the interconnection part 1 is related to the length of the solar cell.

[0113] In some possible embodiments, referring to Figures 4 to 7 , the doped area includes a first doped area 3 and a second doped area 4 which are located on the same side of the silicon substrate 2 and are spaced apart. The first doped area 3 and the second doped area 4 have different doping types, one of which is a P-type doped area and the other is an N-type doped area. In this solar cell, the electrode structure is located on the back side of the silicon substrate 2, and the solar cell is a back contact solar cell. Since there is no electrode on the front side, the solar cell is more beautiful and has better performance. In this case, the solar cell further includes a surface passivation layer 8 located on the front side of the silicon substrate. The specific type of the back contact solar cell is not limited, for example, it can be a BC cell. The electrode structure of the P region and the N region can be one of the electrode structure described above, or the electrode structure of the P region and the N region are both the electrode structure described above, which is not limited in the present application. The interval here can avoid short circuit of the battery.

[0114] In some possible embodiments, referring to Figure 6, the silicon substrate 2 includes: a first side and a second side opposite along the thickness direction E of the silicon substrate 2, one of the first side and the second side is a back side, and the other is a front side. The doped region includes: a first doped region 3 located on the first side of the silicon substrate 2 and a second doped region 4 located on the second side of the silicon substrate 2, one of the two is a P-type doped region, and the other is an N-type doped region. The solar cell is a bifacial solar cell with electrode structures on both the front and back sides. For example, the solar cell can be a TOPCon (passivated contact) cell.

[0115] In some possible embodiments, referring to Figures 1 to 5 , the doped region includes: at least one first doped region 3 and at least one second doped region 4, both of which are located on the same side of the silicon substrate 2, that is, the solar cell is a back contact solar cell. At least one interconnection part 1 covers at least one first doped region 3 and at least one second doped region 4, that is, at least one interconnection part 1 covers at least one P-type doped region and at least one N-type doped region. The interconnection part 1 can be electrically connected to the P-type doped region, or the interconnection part 1 can be electrically connected to the N-type doped region. In the solar cell, the interconnection part 1 does not need to distinguish whether it is electrically connected to the P-type doped region or the N-type doped region. The interconnection part 1 can be compatible with the same process, and the process is simple.

[0116] In some possible embodiments, at least one interconnection part 1 does not cover the first doped region 3 and the second doped region 4, that is, at least one interconnection part 1 does not cover the P-type doped region and the N-type doped region. The P-type doped region or the N-type doped region can be overlapped on the interconnection part 1 to achieve electrical connection. In some possible embodiments, referring to Figure 7 , the first doped region 3 and / or the second doped region 4 are arranged in a polished surface region, and the surface of the interval region is a textured surface region, that is, at least one of the first doped region 3 and the second doped region 4 is arranged in a polished surface region. One possible case is that only one of the first doped region 3 and the second doped region 4 is arranged in a polished surface region. In this case, the texturing process can be reduced, the process steps can be saved, and the production efficiency can be improved. For example, the first doped region 3 is a P-type doped region arranged in a textured surface region, and the second doped region 4 is an N-type doped region arranged in a polished surface region. Another possible case is that, referring to Figures 1 to 10 and Figure 4 , the first doped region 3 and the second doped region 4 are both arranged in a polished surface region, and the surface of the interval region is a textured surface region. Specifically, the first doped region 3 and the second doped region 4 are both arranged in a polished surface region, and the film quality of the first doped region and the second doped region formed is good, which can improve the passivation effect and current collection effect.

[0117] In some possible embodiments, the surface of the silicon substrate 2 comprises a polished surface area and a textured surface area, and the at least partially doped area is arranged on the polished surface area. In particular, the doped area has a better film layer quality on the polished surface area, which can improve the passivation effect.

[0118] In some possible embodiments, the battery body comprises a silicon substrate 2 and a doped area arranged on the silicon substrate, and at least one interconnection part covers at least part of the doped area.

[0119] In some possible embodiments, referring to Figure 6 , the contact electrode comprises a first contact electrode 6 and a second contact electrode 7, the first contact electrode 6 is arranged on the first doped area 3, and the second contact electrode 7 is arranged on the second doped area 4.

[0120] In the present application, the materials of the interconnection part 1, the first contact electrode 6 and the second contact electrode 7 are not limited. For example, the materials of the three can be selected from at least one of a metal, a metal oxide, a metal carbide, a metal sulfide or other conductive materials. The metal can be at least one of Ag (silver), Cu (copper), Al (aluminum), Ni (nickel), Au (gold), Zn (zinc), Sn (tin) and Pb (lead), the metal oxide can be various TCOs (transparent conductive materials) such as ITO, AZO, IWO and the like, the metal nitride can be TiN (titanium nitride) and the like, the metal carbide can be TiC (titanium carbide) and the like, and the other conductive material can be graphene and the like.

[0121] In some possible embodiments, the material of the interconnection part 1 comprises a base metal, which can reduce the cost. For example, the base metal can be at least one of copper, nickel, chromium, lead and aluminum. Firstly, the above-mentioned materials have good conductive properties. Secondly, the above-mentioned materials have low cost, which can reduce the cost of the electrode. Thirdly, the contact electrode has good barrier effect on the above-mentioned materials, which avoids the infiltration of the above-mentioned materials into the silicon substrate and reduces the recombination. Fourthly, the above-mentioned materials can be suitable for low-temperature process formation, which avoids introducing thermal influence into the solar cell.

[0122] In some possible embodiments, the doped regions are all located on the same side of the silicon substrate 2, or in other words, the solar cell is a back contact solar cell: the first contact electrode 6 and the second contact electrode 7 are both non-interrupted contact electrodes, that is, the first contact electrode 6 and the second contact electrode 7 are continuous contact electrodes without being interrupted. The interconnection part 1 is in electrical contact with the first contact electrode 6 covered thereby, and the insulating glue 10 is arranged between the interconnection part 1 and the second contact electrode 7 covered thereby, and the insulating glue 10 is used to avoid short circuit between the interconnection part 1 and the second contact electrode 7 covered thereby. In this case, the interconnection part 1 is used to collect and conduct the current or carriers collected on the first contact electrode 6 covered thereby; or, the interconnection part 1 is in electrical contact with the second contact electrode 7 covered thereby, and the insulating glue 10 is arranged between the interconnection part 1 and the first contact electrode 6 covered thereby, and the insulating glue 10 is used to avoid short circuit between the interconnection part 1 and the first contact electrode 6 covered thereby. In this case, the interconnection part 1 is used to collect and conduct the current or carriers collected on the second contact electrode 7 covered thereby. In this way, the interconnection part 1 can be used to collect and conduct the current or carriers collected on the first contact electrode 6 covered thereby, or the interconnection part 1 can be used to collect and conduct the current or carriers collected on the second contact electrode 7 covered thereby, and in the process of arranging the interconnection part, it is not necessary to distinguish the N region and the P region, and the process is simple.

[0123] In some possible embodiments, referring to Figure 7 , Figure 6 and Figure 7 , at least one interconnection part 1 covers at least one first contact electrode 6 and at least one second contact electrode 7.

[0124] In some possible embodiments, at least one interconnection part 1 does not cover the first contact electrode and the second contact electrode, and one of the first contact electrode and the second contact electrode is electrically connected to the interconnection part through lapping, and the other contact electrode which is not lapped is not electrically connected to the interconnection part, so as to avoid short circuit.

[0125] In some possible embodiments, in the case that at least one interconnection part 1 covers at least one first contact electrode 6 and at least one second contact electrode 7: referring to Figure 6 , the insulating glue 10 is only located on the contact electrode which is not in electrical contact, so as to avoid short circuit between the contact electrode which is not in electrical contact and the interconnection part 1.

[0126] In some possible embodiments, in the case that at least one interconnection part 1 covers at least one first contact electrode 6 and at least one second contact electrode 7: referring to Figure 7, the insulating glue 10 extends from the non-electrically contacted contact electrode to the at least partially spaced area, further enhancing the insulation effect between the non-electrically contacted contact electrode and the interconnection part 1. In addition, in the case where the spaced area is a velvet area, the insulating glue 10 can better combine with the velvet area, thereby increasing the bonding force and reducing the pull-out caused by poor bonding. Moreover, the larger area of the insulating glue 10 can better ensure the process window during the production process and reduce the short circuit or leakage caused by misalignment.

[0127] In some possible embodiments, referring to Figure 4 and Figure 6 , in the case where the interconnection part 1 covers at least one first contact electrode 6 and at least one second contact electrode 7: the insulating glue is arranged between the interconnection part 1 and the non-electrically contacted contact electrode covered by the interconnection part 1, achieving the insulation between the non-electrically contacted contact electrode and the interconnection part 1.

[0128] In some possible embodiments, in the case where the interconnection part 1 covers at least one first contact electrode 6 and at least one second contact electrode 7: the non-electrically contacted contact electrode covered by the interconnection part 1 is disconnected at a position where the interconnection part 1 is located, and the disconnected position achieves the insulation between the non-electrically contacted contact electrode and the interconnection part 1.

[0129] In some possible embodiments, referring to Figure 4 and ​ , in the case where the interconnection part 1 covers at least one first contact electrode 6 and at least one second contact electrode 7: the height of the part of the interconnection part 1 away from the surface of the battery body, the height of the part of the second doped area 4, and the height of the part corresponding to the velvet area covered by the interconnection part 1 decrease in turn. Specifically, the surface of the interconnection part 1 away from the surface of the battery body is the surface where the interconnection part 1 is electrically connected to the interconnection piece in the subsequent process. If the surface has at least the above three heights, the surface is more uneven, refracts and reflects the light incident on it multiple times, so that more light enters the battery body, which can improve the battery efficiency. Due to the existence of the above height difference, the surface area of the surface is larger, on the one hand, the contact area with the interconnection piece is larger, the electrical connection effect with the interconnection piece is better, and the pulling force between the two is larger, and the interconnection piece is less likely to slip off, etc. On the other hand, the interconnection piece is a solder strip, and in the case where the flux is arranged between the interconnection part 1 and the interconnection piece, the above uneven surface allows the flux to stay better, enhancing the welding effect, and the above uneven surface limits the flow of the flux, reducing the risk of short circuit. It should be noted that in the case where the heights decrease in turn, the specific height difference is not limited.

[0130] For example, the height difference between the portion of the interconnection part 1 away from the surface of the battery body and located in the first doped region 3, and the portion of the interconnection part 1 away from the surface of the battery body and located in the second doped region 4, can be 1 μm, 1.5 μm, 2 μm, 2.5 μm, 3 μm, 3.5 μm, 4 μm, 4.5 μm, 5 μm. For another example, the height difference between the portion of the interconnection part 1 away from the surface of the battery body and located in the second doped region 4, and the portion of the interconnection part 1 away from the surface of the battery body and located in the portion of the textured region corresponding to the second doped region 4, can be 1 μm, 1.5 μm, 2 μm, 2.5 μm, 3 μm, 3.5 μm, 4 μm, 4.5 μm, 5 μm, 5.5 μm, 6 μm, 6.5 μm, 7 μm, 7.5 μm, 8 μm, 8.5 μm, 9 μm, 9.5 μm, 10 μm.

[0131] The application also provides a battery string comprising the interconnection member and a plurality of any of the foregoing solar cells, the interconnection member being electrically connected with the interconnection part 1 in the solar cells. The solar cells comprise the intersecting first edge 91 and second edge 92, in the battery string, the interconnection member is arranged along the extension direction of the second edge 92, then in combination with the aforementioned difference in arrangement of the interconnection part at the first edge and the second edge, the combination effect of the interconnection part 1 and the interconnection member can be further improved, the pulling force between the two is greater, and the risk of slipping or falling off between the two is reduced. Please refer to the foregoing related description, and no further description is given here to avoid repetition.

[0132] For example, in the battery string, along the extension direction of the second edge 92, the interconnection member electrically connects the electrode structure electrically connected with the N-type doped region in one of the two adjacent solar cells, and the electrode structure electrically connected with the P-type doped region in the other solar cell.

[0133] The application also provides a photovoltaic module comprising a plurality of battery strings connected in series and / or parallel along the extension direction of the interconnection member, the battery strings are connected in series and / or parallel along the extension direction of the interconnection member, the electrical connection effect is better, the pulling force between the battery strings is greater, and the risk of slipping or falling off between the two is reduced.

[0134] It should be noted that the solar cells, battery strings and photovoltaic modules provided by the application are related to each other and can be referred to each other, and no further description is given here to avoid repetition.

[0135] The application will be further explained in combination with specific examples.

[0136] Example 1

[0137] a. Silicon wafer surface treatment to obtain a silicon substrate. The silicon wafer is subjected to surface treatment, such as damage removal, stain removal, polishing, or texturing treatment, etc. An intrinsic semiconductor layer (or a doped layer, such as in the b step) is formed.

[0138] b. Form a first auxiliary film on the surface and prepare a semiconductor layer on the silicon substrate (the doping of the intrinsic semiconductor can be completed at this step, if the semiconductor has been doped in step a, then this step can only form a mask layer).

[0139] For example, specifically, the intrinsic amorphous silicon layer in step a can be doped by boron diffusion to form a first doped layer, i.e. a P-type polysilicon layer. The thickness of the polysilicon layer is 50-500 nm. An interface passivation layer can be provided between the P-type polysilicon layer and the silicon substrate, and the interface passivation layer 5 in this embodiment is a tunnel oxide layer. The thickness of the tunnel oxide layer is 0.5-5 nm. Then a silicon oxide mask is prepared on the first doped layer.

[0140] Of course, the intrinsic semiconductor can also be formed in step a, and then in step b, P-type doping of the semiconductor and formation of a BSG (borosilicate glass layer) mask layer thereon can be completed in one step under high temperature and in the presence of BCl3 and oxygen.

[0141] c. The mask (e.g. BSG) is patterned, and the first doped layer thereunder is patterned using the mask to obtain first doped regions 3 spaced apart.

[0142] For example, the BSG is patterned using a laser, and then the first doped layer is patterned using KOH or NaOH.

[0143] d. The intrinsic semiconductor layer is prepared. An interface passivation layer between the intrinsic semiconductor layer and the silicon substrate can also be prepared.

[0144] e. Similarly, the intrinsic semiconductor layer is doped to obtain an N-type doped layer, and a mask layer thereon is prepared.

[0145] Steps d and e, like steps a and b, can be separated into deposition of a doped layer and preparation of a mask layer (e.g. PSG, phosphosilicate glass). The doping step can be completed in step d or step a, and the doping step can also be completed in step e or step b.

[0146] f. and g. Similarly to step c, the mask on the second doped layer is patterned, and the second doped layer is patterned to obtain second doped regions.

[0147] h. The masks (e.g. BSG and PSG) of the first regions and the second regions are removed.

[0148] i. The surface passivation step is completed.

[0149] The surface passivation layer 8 is formed on the front and back surfaces of the structure formed in step h. The surface passivation layer 8 can be composed of one or more of silicon nitride, silicon oxide, silicon oxynitride, aluminum oxide, silicon carbide, and amorphous silicon.

[0150] The surface passivation layer 8 can be single layer or multi-layer. For example, a layer of aluminum oxide is first prepared by ALD (atomic layer deposition) method, and then a layer or multiple layers of silicon nitride are formed thereon by PECVD (plasma enhanced chemical vapor deposition).

[0151] j. complete metallization, and complete the preparation of electrode structure in the first region and the second region of the battery.

[0152] The formed solar cell refers to ​ The solar cell includes a silicon substrate 2 and a doped region arranged on the back side of the silicon substrate 2, the doped region includes a first doped region 3 and a second doped region 4 both located on the back side of the silicon substrate 2 and spaced apart, wherein the first doped region 3 is a P-type doped region and the second doped region 4 is an N-type doped region. The electrode structure includes a first contact electrode 6 electrically connected to the first doped region 3, a second contact electrode 7 electrically connected to the second doped region 4, an interconnection part arranged on the side of the contact electrode away from the battery body, the contact electrode extends along the extension direction of the first edge 91, the interconnection part 1 is spaced apart along the extension direction of the second edge 92, the interconnection part 1 covers at least one first contact electrode 6 and at least one second contact electrode 7, and the interconnection part 1 is electrically connected to the first contact electrode 6 or the second contact electrode 7. The contact electrode is also provided with a segmented busbar, which is electrically connected to the interconnection part. The first doped region 3 and the second doped region 4 are both arranged in the polished surface region, and the spacing region is a textured surface region.

[0153] The solar cell includes intersecting first edge 91 and second edge 92, and the interconnection part 1 includes first end and second end opposite to each other along the extension direction of the second edge 92, the surface area covered by the first end and the second end of all interconnection parts 1 is the polished surface region, and the surface area covered by the part other than the first end and the second end of the interconnection part 1 contains at least the textured surface region. Along the extension direction F of the second edge 92: the length of the first end accounts for about 2% of the length of the interconnection part 1, and the length of the second end also accounts for about 2% of the length of the interconnection part 1. The covered surface area of all interconnection parts 1 includes the textured surface region and the polished surface region; each interconnection part 1 is in direct contact with the textured surface region of the underlying surface passivation layer 8. In the battery body, the area ratio of the textured surface region in the covered surface area of each interconnection part 1 is about 5%.

[0154] First, the bonding force between the interconnection 1 and the cell body of the solar cell of Example 1 was tested. The specific test method was as follows: using 3M transparent tape for bonding, and 180° uniform speed pulling test with the cell surface, 196 interconnections were bonded at one time, the proportion of interconnections pulled off was tested, and the test results are shown in Table 1 below. Then, the bonding force between the interconnection 1 and the interconnection piece of the solar cell of Example 1 was tested. The specific test method was as follows: using 0.6 mm wide solder strip to complete welding, the extension direction of the interconnection piece was parallel to the extension direction of the second side, and during the test, 180° uniform speed pulling test was performed with the cell surface, the pulling speed was 300 mm / min, the average value of the peak force of each segmented busbar line was taken, and the test results are shown in Table 1 below.

[0155] For Examples 2 to 9 and Comparative Example 1, only the differences from Example 1 are described below, and the same parts are not limited.

[0156] Example 2

[0157] In the cell body, the area ratio of the textured area in the surface area covered by each interconnection 1 was about 10%.

[0158] Example 3

[0159] In the cell body, the area ratio of the textured area in the surface area covered by each interconnection 1 was about 20%.

[0160] Example 4

[0161] In the cell body, the area ratio of the textured area in the surface area covered by each interconnection 1 was about 25%.

[0162] Example 5

[0163] In the cell body, the area ratio of the textured area in the surface area covered by each interconnection 1 was about 30%.

[0164] Example 6

[0165] In the cell body, the area ratio of the textured area in the surface area covered by each interconnection 1 was about 35%.

[0166] Example 7

[0167] In the cell body, the area ratio of the textured area in the surface area covered by each interconnection 1 was about 40%.

[0168] Example 8

[0169] In the cell body, the area ratio of the textured area in the surface area covered by each interconnection 1 was about 45%.

[0170] Example 9

[0171] In the battery body, the proportion of the area of the suede area in the surface area covered by each interconnecting portion 1 is about 50%.

[0172] Example 10

[0173] The surface area covered by the first end and the second end of all interconnecting portions 1 is the suede area, and the surface area covered by the part other than the first end and the second end of the interconnecting portion 1 at least contains the suede area. In the battery body, the proportion of the area of the suede area in the surface area covered by each interconnecting portion 1 is about 20%.

[0174] Example 11

[0175] In both the first end and the second end of all interconnecting portions 1, the surface area covered by one end close to the edge of the battery body is the suede area, and the surface area covered by the other end is the polished surface area, and the surface area covered by the part other than the first end and the second end at least contains the suede area. In the battery body, the proportion of the area of the suede area in the surface area covered by each interconnecting portion 1 is about 20%.

[0176] Comparative Example 1

[0177] The surface area covered by the first end and the second end of all interconnecting portions 1 is the polished area, and the surface area covered by the part other than the first end and the second end of the interconnecting portion 1 is also the polished surface area. That is, in the battery body, the proportion of the area of the suede area in the surface area covered by each interconnecting portion 1 is 0%.

[0178] Table 1: Comparison table of parameters of examples and comparative examples

[0179]

[0180] By comparing the above examples 1 to 11 with the comparative example 1, it can be concluded that in the present application, the surface area covered by the interconnecting part includes the suede area and the polished surface area, and the interconnecting part is in direct contact with the suede area covered thereunder, the contact area between the suede area and the interconnecting part is large, which improves the bonding force between the interconnecting part and the battery body, and the combination of the two is more firm and not easy to pull off or fall off; moreover, the part of the interconnecting part arranged in the suede area is far away from the surface of the battery body, which is rough or less flat, thereby increasing the contact area between the interconnecting part and the interconnecting piece and improving the bonding force between the interconnecting part and the interconnecting piece; in addition, the part of the interconnecting part formed on the polished surface area has good quality, which realizes the optimized balance of the quality of the interconnecting part, the bonding force between the interconnecting part and the battery body, and the bonding force between the interconnecting part and the interconnecting piece. By comparing examples 1 to 9, it can be concluded that in the case where the surface area covered by the first end and the second end of all interconnecting parts 1 is the polished surface area, and the surface area covered by the part other than the first end and the second end of the interconnecting part 1 contains at least the suede area, as the area ratio of the suede area covered by the interconnecting part 1 increases, the bonding force between the interconnecting part and the battery body, and the bonding force between the interconnecting part and the interconnecting piece are both increased. By comparing examples 3 and 10 and 11, it can be concluded that in the case where the area ratio of the suede area covered by the interconnecting part 1 is the same, and at least one end of the two ends covers the suede area, the bonding force between the interconnecting part and the interconnecting piece is increased. By comparing examples 10 and 11, it can be concluded that in the case where the area ratio of the suede area covered by the interconnecting part 1 is the same, and both ends cover the suede area, the bonding force between the interconnecting part and the battery body, and the bonding force between the interconnecting part and the interconnecting piece are both greater.

[0181] It should be noted that in this document, the terms "comprising", "including", or any other variant thereof are intended to cover a non-exclusive inclusion, so that a process, method, article, or apparatus that includes a list of elements not only includes those elements, but also includes other elements not expressly listed or inherent to such process, method, article, or apparatus. Without more limitations, an element defined by the statement "comprising a" does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0182] The embodiments of the present application are described above in conjunction with the drawings, but the present application is not limited to the specific embodiments described above, and the specific embodiments described above are only illustrative, not restrictive, and those of ordinary skill in the art can make many forms under the inspiration of the present application without departing from the purpose of the present application and the scope protected by the claims.

Claims

1. A solar cell, characterized by, The battery body comprises a first edge and a second edge intersecting each other; The electrode structure comprises a plurality of contact electrodes and a plurality of interconnections, the interconnections are arranged on the side of the contact electrodes away from the battery body, the contact electrodes extend along the extension direction of the first edge, the interconnections are spaced along the extension direction of the second edge, the electrode structure is electrically connected with the battery body; the surface area covered by at least one of the interconnections comprises a suede area and a polished surface area; at least one of the interconnections is in direct contact with at least part of the suede area underneath. The plurality of interconnections comprises edge interconnections located in the edge region of the battery body and intermediate interconnections located in the intermediate region of the battery body; In the battery body, the area ratio of the suede area in the surface area covered by one of the edge interconnections is greater than or equal to the area ratio of the suede area in the surface area covered by one of the intermediate interconnections.

2. The solar cell according to claim 1, characterized in that, In the battery body, the area ratio of the suede area in the surface area covered by one of the interconnections is greater than or equal to 5%. The interconnection comprises a first end and a second end opposite along the extension direction of the second edge; 3. The solar cell according to claim 1, characterized in that, In the battery body, at least one of the first end and the second end of the interconnection covers a suede area.

4. The solar cell of claim 1, wherein In the battery body, the surface area covered by the interconnection comprises: the suede area and the polished surface area are alternately distributed along the extension direction of the second edge. In the battery body, the surface area covered by one of the interconnections comprises: the number of the suede area and the polished surface area along the extension direction of the second edge is greater than or equal to 2.

5. The solar cell of claim 1, wherein At least part of the surface of the interconnection away from the battery body is recessed towards the side of the battery body.

6. The solar cell according to claim 5, characterized in that, The battery body comprises a silicon substrate and a doped region arranged on the silicon substrate; adjacent doped regions have a spacing region; at least one of the interconnections covers at least part of the doped region and at least part of the spacing region; at least part of the doped region and at least one adjacent spacing region have a height difference.

7. The solar cell of claim 1, wherein The doped regions are located on the same side of the silicon substrate, and the first doped region and the second doped region are spaced apart; the doping types of the first doped region and the second doped region are different.

8. The solar cell of claim 1, wherein, Or, 9. The solar cell according to claim 8, characterized in that, The silicon substrate comprises a first side and a second side opposite along its thickness direction; the doped regions comprise a first doped region located on the first side of the silicon substrate and a second doped region located on the second side of the silicon substrate; the doping types of the first doped region and the second doped region are different. The doped regions are located on the same side of the silicon substrate: at least one of the interconnections covers at least one of the first doped regions and at least one of the second doped regions. The first doped region and / or the second doped region is arranged on the polished surface area, and the surface of the spacing region is a suede area.

10. The solar cell of claim 9, wherein, ​ 11. The solar cell of claim 9, wherein, ​ 12. The solar cell of claim 9, wherein, The contact electrodes include: a first contact electrode and a second contact electrode; the first contact electrode is arranged on the first doped region, and the second contact electrode is arranged on the second doped region; The doped regions are located on the same side of the silicon substrate: the first contact electrode and the second contact electrode are non-interrupted contact electrodes; The interconnecting part is in electrical contact with the first contact electrode covered thereby, and an insulating adhesive is arranged between the interconnecting part and the second contact electrode covered thereby; or, The interconnecting part is in electrical contact with the second contact electrode covered thereby, and an insulating adhesive is arranged between the interconnecting part and the first contact electrode covered thereby.

13. The solar cell of claim 12, wherein, In the case where the interconnecting part covers at least one first contact electrode and at least one second contact electrode: The insulating adhesive is only located on the contact electrodes that are not in electrical contact; or, The insulating adhesive extends from the contact electrodes that are not in electrical contact to at least part of the spacing regions.

14. The solar cell of claim 12, wherein, In the case where the interconnecting part covers at least one first contact electrode and at least one second contact electrode: The height of the part of the interconnecting part located in the surface of the battery body away from the battery body, the height of the part of the first doped region, and the height of the part of the second doped region corresponding to the part of the textured region covered thereby decrease in turn.

15. The solar cell according to claim 8, characterized in that, At least one interconnecting part covers at least two contact electrodes of the same polarity; and / or At least one interconnecting part covers 3 doped regions and 2 to 4 spacing regions.

16. The solar cell according to any one of claims 1 to 15, wherein, The battery body includes: a silicon substrate, a doped region, and an interface passivation layer located between the silicon substrate and the doped region; and / or, The doped region includes: at least one of doped microcrystalline silicon, doped amorphous silicon, and doped polycrystalline silicon; and / or, The polished surface region has a textured structure; and / or, The flatness of the polished surface region is less than the flatness of the textured region; and / or, the surface reflectivity of the polished surface region is greater than the surface reflectivity of the textured region; and / or, the material of the interconnecting part includes a base metal; and / or, Along the extension direction of the second edge, adjacent interconnecting parts are connected by a conductive part.

17. The solar cell of claim 16, wherein, The battery body further includes: a surface passivation layer arranged on the side of the doped region away from the silicon substrate; The interconnecting part is in direct contact with at least part of the textured region of the silicon substrate; and / or, The interconnecting part is in direct contact with at least part of the textured region of the doped region; and / or, The interconnecting part is in direct contact with at least part of the textured region of the interface passivation layer; and / or, The interconnecting part is in direct contact with at least part of the textured region of the surface passivation layer.

18. A string of batteries, characterized in that It includes: An interconnecting member, and a plurality of solar cells according to any one of claims 1 to 17; The interconnecting member is in electrical connection with the interconnecting part of the solar cell; and the interconnecting member is arranged along the extension direction of the second edge.

19. A photovoltaic device, characterized by Along the extension direction of the interconnecting member, a plurality of battery strings according to claim 18 are connected in series and / or in parallel.

Images