A solar cell and photovoltaic module

Abstract

This invention discloses a solar cell and a photovoltaic module, relating to the field of photovoltaic technology, to reduce the overprinting difficulty between a first contact portion and a first transmission portion. The solar cell includes a semiconductor substrate, a first doped semiconductor portion, a passivation layer, and a plurality of first current collector structures. In the same first current collector structure, a first transmission portion extends along a first direction, and a plurality of first contacts are spaced apart along the first direction, with the length of each first contact portion being greater than its width along the first direction. The first contact portion passes through the passivation layer and is electrically connected to a first strip-shaped region, and the first transmission portion is disposed on the side of the first contact portion facing away from the semiconductor substrate. The length of at least one first contact portion is greater than or equal to 30 μm and less than or equal to 75% of the width of the first strip-shaped region electrically connected to the first contact portion; and / or, in at least one first current collector structure, the ratio of the width of the first transmission portion to the length of at least one first contact portion is greater than or equal to 10% and less than or equal to 200%.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic technology, and more particularly to a solar cell and a photovoltaic module. Background Technology

[0002] Although solar cell technology has made significant progress, it still faces many challenges in areas such as cell efficiency and cost control. Furthermore, the electrodes of a solar cell not only collect and transmit the current generated by photogenerated charges, but also affect the overall efficiency and performance of the cell.

[0003] To achieve a good passivation effect, the current collector structure is typically designed to include a transport section and multiple spaced-apart contacts. The contacts penetrate the passivation layer and are electrically connected to the doped portion that collects charge carriers in the battery. The transport section is located on the side of the multiple contacts away from the doped portion. In this case, the passivation layer between adjacent contacts can be retained, increasing the passivation area and helping to reduce carrier recombination. However, during the manufacturing process of this current collector structure, processing errors in the manufacturing equipment can lead to misalignment between the contacts and the transport section, resulting in the transport section being misaligned and unable to connect with the contacts, thus preventing charge carriers from being discharged. Summary of the Invention

[0004] The purpose of this invention is to provide a solar cell and a photovoltaic module that reduces the overlay difficulty between the first contact portion and the first transmission portion in the first collector structure, thereby facilitating the electrical connection between the first transmission portion and the first contact portion and the effective collection and export of charge carriers.

[0005] To achieve the above objectives, in a first aspect, the present invention provides a solar cell comprising: a semiconductor substrate, a first doped semiconductor portion, a passivation layer, and a plurality of first current collector structures. The semiconductor substrate includes opposing first and second surfaces. The first doped semiconductor portion is disposed in a portion region of or on the first surface of the semiconductor substrate. The first doped semiconductor portion includes a plurality of first strip-shaped regions extending along a first direction and spaced apart along a second direction. The first and second directions intersect. The passivation layer is disposed on a side of the first doped semiconductor portion away from the semiconductor substrate. The plurality of first current collector structures are disposed on the passivation layer corresponding to the first doped semiconductor portion. Each first current collector structure includes a first transmission portion and a plurality of first contact portions electrically connected to the first transmission portion. In the same first current collector structure, the first transmission portion extends along the first direction, and the plurality of first contact portions are spaced apart along the first direction, with the length of each first contact portion along the second direction being greater than its width along the first direction. The plurality of first contact portions pass through the passivation layer and are electrically connected to the first strip-shaped regions, and the first transmission portion is disposed on a side of the first contact portion away from the semiconductor substrate. Wherein, along the second direction, the length of at least one first contact portion is greater than or equal to 30 μm and less than or equal to 75% of the width of the first strip region electrically connected to the first contact portion; and / or, in at least one first collector structure, the ratio of the width of the first transmission portion to the length of at least one first contact portion is greater than or equal to 10% and less than or equal to 200%.

[0006] When the above technical solution is adopted, the length of the first contact portion along the second direction is greater than the width of the first contact portion along the first direction. Even if there are processing errors in the manufacturing equipment for manufacturing the first contact portion and the first transmission portion, causing the actual formation position of the first contact portion or the first transmission portion to deviate from the initial design position along the second direction, the larger length of the first contact portion in the second direction can accommodate the positional offset and misalignment of the first contact portion and the first transmission portion along the second direction caused by the above deviation. This improves the overprinting tolerance and production yield of the two, which is conducive to ensuring that the first transmission portion can be electrically connected to the first contact portion, and facilitates the effective collection and export of charge carriers.

[0007] Based on the above design, while improving the misregistration problem of the first contact portion and the first transmission portion, the design of the first contact portion and the first transmission portion still needs to consider the matching of factors such as carrier collection effect, passivation damage, and cost. Therefore, this application designs at least one of the first contact portions with a length greater than or equal to 30 μm along the second direction. This prevents the transmission resistance of carriers to the first contact portion from being too small, which would reduce the power generation efficiency. Furthermore, when the first contact portion is formed by printing, a first contact portion with too small a length will result in insufficient ink flow on the printing screen, leading to less ink paste for printing the first contact portion. Less ink paste will prevent effective penetration through the passivation layer to form an effective contact, which also helps to improve the misregistration tolerance of the first contact portion and the first transmission portion and facilitates carrier collection. Secondly, setting the length of the first contact portion to be less than or equal to 75% of the width of the first strip area can ensure effective collection on the one hand, and prevent excessive offset of the first contact portion due to problems such as stencil deformation or positioning misalignment after mass printing. This could lead to printing outside the first strip area, further causing other contact defects or passivation losses, and thus reducing efficiency and yield. In addition, it can also prevent excessive consumption of electrode material for manufacturing the first contact portion due to excessive length, which is beneficial for controlling manufacturing costs. Furthermore, it can reduce the loss of the passivation layer caused by manufacturing the first contact portion, which is conducive to the passivation layer having a good passivation effect.

[0008] Based on this, by controlling the length of the first contact portion so that the impact of carrier transmission and passivation losses on efficiency is small, the ratio of the width of the first transmission portion to the length of the first contact portion is set to be greater than or equal to 10% and less than or equal to 200%. This can also prevent the width of the first transmission portion from being too large, which is beneficial to controlling manufacturing costs; and it can also prevent the transmission resistance of the first transmission portion from being too large due to its width being too small, thereby avoiding transmission loss.

[0009] As one possible implementation, along the second direction, the length of at least one first contact portion is greater than or equal to 50 μm.

[0010] As one possible implementation, in at least one first collector structure, the ratio of the width of the first transmission section to the length of at least one first contact section is greater than or equal to 10% and less than or equal to 100%. This configuration not only solves the misalignment between the first contact section and the first transmission section, but also further reduces the width of the first transmission section and lowers its cost.

[0011] As one possible implementation, in at least one first collector structure, the spacing between two adjacent first contacts is greater than or equal to the length of the first contact. Because the length of the first contact along the second direction is greater than its width along the first direction, the first contact and the first transmission part can meet a larger overprinting tolerance, giving the first transmission part more room for cost reduction. However, this leads to increased mold opening losses. Therefore, designing the spacing between two adjacent first contacts to be greater than or equal to the length of the first contact can prevent the first collector structure from having too many first contacts due to the spacing between two adjacent first contacts being too small, thereby preventing the manufacturing cost of the first contacts from being too high. Furthermore, it can also reduce the loss of the passivation layer caused by manufacturing the first contacts, which is beneficial for the passivation layer to have a good passivation effect.

[0012] As one possible implementation, in at least one first collector structure, the ratio of the length of the first contact portion to the distance between two adjacent first contacts is greater than or equal to 15% and less than or equal to 100%.

[0013] By employing the above technical solution, it is possible to prevent the length of the first contact portion from being too small and / or the spacing between two adjacent first contacts from being too large due to an excessively small ratio. This is beneficial for improving the overprinting tolerance between the first contact portion and the first transmission portion, while reducing the transmission loss of charge carriers located on both sides of the first contact portion along the second direction to the first contact portion, as well as reducing the transmission loss of charge carriers located on both sides of the first contact portion along the first direction to the first contact portion. In addition, it is also possible to prevent the length of the first contact portion from being too large and / or the spacing between two adjacent first contacts from being too small due to an excessively large ratio, thereby reducing the manufacturing cost of the first contact portion and reducing the probability that at least one end of the first contact portion along the second direction is printed outside the first strip area, thus reducing the risk of leakage current due to direct contact between the first contact portion and the semiconductor substrate.

[0014] As one possible implementation, in at least one first collector structure, the distance between two adjacent first contacts is greater than or equal to 50 μm and less than or equal to 300 μm. The beneficial effects in this case are similar to those described above regarding preventing the distance between two adjacent first contacts from being too large or too small, and will not be repeated here.

[0015] As one possible implementation, the length of at least one first contact portion is greater than or equal to 50 μm and less than or equal to 150 μm. The beneficial effects in this case can be referred to the previously described advantages in preventing the length of at least one first contact portion from being too large or too small, and will not be repeated here.

[0016] As one possible implementation, along the second direction, the length of at least one first contact portion is greater than or equal to 10% of the width of the first strip region electrically connected to the first contact portion. This approach can further reduce the transmission resistance of charge carriers along the second direction to the first contact portion, improving power generation efficiency; it also further reduces the misalignment between the first contact portion and the first transmission portion, lowering the manufacturing difficulty; furthermore, setting the length of the first contact portion to be greater than or equal to 10% of the width of the first strip region electrically connected to the first contact portion increases the length of the first contact portion, thus increasing ink leakage when forming the first contact portion using a printing process, resulting in a better linear shape of the first contact portion, and allowing for more effective contact between the first contact portion and the first doped semiconductor portion.

[0017] Optionally, along the second direction, the length of at least one first contact portion is greater than or equal to 20% of the width of the first strip region electrically connected to the first contact portion.

[0018] Optionally, along the second direction, the length of at least one first contact portion is greater than or equal to 30% of the width of the first strip region electrically connected to the first contact portion.

[0019] As one possible implementation, along the second direction, the width of at least one first transmission section is greater than or equal to 20 μm and less than or equal to 90 μm.

[0020] When the width of at least one first transmission portion is within the aforementioned range, excessive transmission line resistance due to an excessively small width of the first transmission portion can be prevented, thus reducing transmission loss. Furthermore, since the length of the first contact portion along the second direction is greater than its width along the first direction, printing is required along the second direction when forming the first contact portion using a printing process. However, the path height of the squeegee along the second direction varies, necessitating a width of the first transmission portion greater than or equal to 20 μm to ensure sufficient ink leakage and thus better linearity of the first contact portion. This allows for more effective contact between the first contact portion and the first doped semiconductor portion. Additionally, excessive electrode material consumption due to an excessively large width of the first transmission portion can be prevented, helping to control manufacturing costs. Simultaneously, the shading effect of the first transmission portion can be reduced, improving the light utilization rate of the solar cell.

[0021] As one possible implementation, along the first direction, the width of at least one first contact portion is greater than or equal to 8 μm and less than or equal to 30 μm.

[0022] When the width of at least one first contact portion is within the aforementioned range, it can prevent the manufacturing difficulty of forming the printing screen for printing the first contact portion from becoming too high due to the width of the first contact portion being too small, thus reducing the manufacturing precision requirements. Furthermore, it can prevent the material consumption of the first contact portion from becoming too large due to the width of the first contact portion, thereby reducing the manufacturing cost of the first contact portion; simultaneously, it can reduce the loss of the passivation layer caused by manufacturing the first contact portion, which is beneficial for the passivation layer to have a good passivation effect.

[0023] As one possible implementation, the ratio between the length of at least one first contact portion and its width is greater than or equal to 1.5 and less than or equal to 20. The beneficial effect in this case can be understood by referring to the previously described principles for preventing the length and width of the first contact portion from being too large or too small, and will not be repeated here.

[0024] As one possible implementation, along the second direction, the minimum distance between the end of the first contact portion and the edge of the first strip-shaped area electrically connected to the first contact portion is defined as L1. Along the first direction, the distance between two adjacent first contacts in the first collector structure is defined as L2. Along the first direction, the minimum distance between the end of the first transmission portion and the edge of the first strip-shaped area electrically connected to the first transmission portion is defined as L3. Wherein, L1 and 0.5... The difference in L2 is greater than or equal to -100 μm and less than or equal to 370 μm; and / or, L1 is greater than or equal to 50 μm and less than 300 μm; and / or, L3 is greater than or equal to 50 μm and less than 150 μm.

[0025] When the above technical solution is adopted, when L1 is equal to 0.5 When the difference of L2 is within the above range, it is beneficial to make the distance of the charge carriers in the first strip portion to the nearest first contact portion along the first direction closer to the distance of the charge carriers in the first strip portion to the nearest first contact portion along the second direction, which is beneficial to the collection of more charge carriers and the reduction of charge carrier recombination.

[0026] Furthermore, when L1 is within the aforementioned range, it can prevent the carriers from becoming too small, and the beneficial effects of this can be found in the preceding text. Secondly, it can also prevent the length of the first contact portion from becoming too small due to an excessively large L1, which would result in high transmission losses of carriers along the second direction to the first contact portion, thus reducing carrier recombination. At the same time, it also helps to improve the overprinting tolerance of the first contact portion and the first transmission portion, thereby improving manufacturing yield.

[0027] Furthermore, when L3 is within the aforementioned range, it prevents the length of the first transmission section from becoming too large due to an excessively small L3, which helps reduce the manufacturing cost of the first transmission section and decrease its light-shielding area. Additionally, in the case of a back-contact solar cell, it prevents the requirements for printing the first and second current collector structures and / or the risk of leakage from becoming too high due to the distance between the end of the first transmission section along the first direction and the second current collector structure with opposite polarity being too close. Secondly, it also prevents the carriers in the edge regions on both sides of the first strip region along the first direction from needing to travel a long distance to be collected and discharged by the first contact section and the first transmission section due to an excessively large L3, thus reducing carrier recombination at the edge regions on both sides of the first strip region along the first direction.

[0028] As one possible implementation, in at least one first current collector structure, the distance between the centerline of the first contact portion extending along the first direction and the centerline of the first transmission portion extending along the first direction is greater than or equal to 0 and less than or equal to half the length of the first contact portion. This arrangement helps reduce the transmission resistance of charge carriers from the first contact portion to the first transmission portion, thus reducing losses. Simultaneously, it avoids the problem of uneven charge carrier transmission in different regions of the first contact portion along the second direction, thereby improving the conversion efficiency of the solar cell.

[0029] As one possible implementation, in the same first collector structure, the length of the orthographic projection of at least one first contact portion onto the first transmission portion along the second direction is greater than or equal to half the width of the first transmission portion. This arrangement helps to achieve a larger effective contact area between the first transmission portion and the first contact portion, reducing contact resistance and facilitating the timely extraction of charge carriers.

[0030] As one possible implementation, in the same first collector structure, the lengths of multiple first contacts are the same; and / or, the two ends of the multiple first contacts along the second direction are respectively flush. This arrangement is beneficial because each first contact has a large length, thereby having a high carrier collection capacity, which is conducive to the timely discharge of carriers collected in each region within the first strip-shaped region.

[0031] In addition, when the two ends of the multiple first contact portions are flush along the second direction, it is beneficial to ensure that each first contact portion has at least a portion that can be electrically connected to the first transmission portion, thereby improving the overprinting tolerance between each first contact portion and the first transmission portion; at the same time, it reduces the transmission resistance of charge carriers from the first contact portion to the first transmission portion, thereby reducing losses.

[0032] As one possible implementation, in the same first collector structure, the first transmission unit is electrically connected to a row of first contacts. The centerlines of multiple first contacts in the same row, extending along a first direction, coincide. The application principle of the beneficial effect in this case can be referenced from the application principle of the beneficial effect described above where the two ends of multiple first contacts are aligned along a second direction, and will not be repeated here.

[0033] As one possible implementation, the solar cell further includes multiple sets of first electrical junctions disposed on a passivation layer corresponding to the first doped semiconductor portion. The multiple sets of first electrical junctions are spaced apart along a first direction, and each set includes a plurality of first electrical junctions spaced apart along a second direction. Each first electrical junction is electrically connected to a corresponding first current collector structure. The first electrical junctions overlap with at least one first contact portion; and / or, along the second direction, the width of at least one first electrical junction is greater than or equal to the length of the first contact portion.

[0034] When the above technical solution is adopted, if the first electrical bonding portion overlaps with at least one first contact portion, the charge carriers collected by the first contact portion can be directly transported to the first electrical bonding portion via the first transmission portion and along the thickness direction of the semiconductor substrate. This helps to shorten the transport path of the charge carriers within the first transmission portion and reduce transmission losses. Furthermore, the increased surface roughness of the first electrical bonding portion improves the welding effect.

[0035] In addition, when the width of at least one first electrical junction is greater than or equal to the length of the first contact portion, it can prevent the manufacturing cost of the first contact portion from being too high due to the excessive length of the first contact portion; secondly, it can also prevent the bonding force between the interconnect structure used to connect two adjacent solar cells in series and the first electrical junction portion from being too small due to the width of the first electrical junction portion, thereby reducing the risk of the interconnect structure falling off.

[0036] As one possible implementation, the solar cell further includes a second doped semiconductor portion, a plurality of second current collector structures, and a plurality of sets of second electrical connections. The second doped semiconductor portion is disposed in a portion of a first surface of the semiconductor substrate, and the conductivity type of the second doped semiconductor portion is opposite to that of the first doped semiconductor portion. The second doped semiconductor portion includes a plurality of second strip-shaped regions extending along a first direction and spaced apart along a second direction. The second strip-shaped regions and the first strip-shaped regions are alternately distributed along the second direction. A passivation layer is also disposed on the side of the second doped semiconductor portion facing away from the semiconductor substrate. Each second current collector structure is electrically connected to a second strip-shaped region through the passivation layer. The plurality of sets of second electrical connections are spaced apart along the first direction. Each set of second electrical connections includes a plurality of second electrical connections spaced apart along the second direction, and each second electrical connection is electrically connected to a corresponding second current collector structure. In at least one first current collector structure, a first transmission portion is disconnected at the intersection with the extension line of each set of second electrical connections, and the spacing between two adjacent first contacts near the disconnection point of the first transmission portion in the first current collector structure is different from the spacing between two adjacent first contacts away from the disconnection point of the first transmission portion.

[0037] When the above technical solution is adopted, as shown above, the first transmission section is disconnected at the intersection with the extension line of each group of second electrical junctions to prevent short circuits. Furthermore, in this first collector structure, the spacing between two adjacent first contacts near the disconnection point of the first transmission section is different from the spacing between two adjacent first contacts away from the disconnection point. In this case, waste in the first strip region is reduced, large dead zones are prevented at the edge of the first strip region at the disconnection point, and carrier recombination is reduced.

[0038] As one possible implementation, within the same group of second electrical junctions, the region between two adjacent second electrical junctions is defined as the first region. The region between two adjacent groups of second electrical junctions is defined as the second region. The spacing between two first contacts located in the first region and adjacent along the first direction is different from the spacing between two first contacts located in the second region and adjacent along the first direction. This arrangement allows for a reasonable setting of the spacing between two adjacent first contacts near the break point based on the distance of the first transmission section disconnection. This prevents the spacing between two adjacent first contacts near the boundary between the first and second regions from being too small, which would lead to high manufacturing costs and poor passivation effect of the passivation layer near the boundary. Furthermore, it prevents the spacing between two adjacent first contacts near the boundary between the first and second regions from being too large, which would lead to high carrier transport losses near the boundary and reduce carrier recombination.

[0039] As one possible implementation, the solar cell further includes multiple second terminal lines. Each second terminal line is disposed on at least one side of each group of second electrical junctions along a second direction and is electrically connected to the outermost second electrical junction in that group. The first strip region is interrupted at its intersection with the second terminal lines, and the distance from the edge of the first contact closest to the edge of the interruption of the first strip region to the edge of the first strip region is L4. L4 is smaller than the spacing between two adjacent first contacts. This arrangement prevents excessive transport losses of charge carriers from the edge of the interruption of the first strip region to the nearest first contact due to an excessively large L4, thereby reducing carrier recombination.

[0040] As one possible implementation, the solar cell further includes a second doped semiconductor portion and a plurality of second current collector structures. The second doped semiconductor portion is disposed in a portion of a first surface of the semiconductor substrate or on it. The second doped semiconductor portion includes a plurality of second strip-shaped regions extending along a first direction and spaced apart along a second direction. The second strip-shaped regions and the first strip-shaped regions are alternately distributed along the second direction. A passivation layer is also disposed on the side of the second doped semiconductor portion facing away from the semiconductor substrate. The plurality of second current collector structures are disposed on the passivation layer corresponding to the second doped semiconductor portion. Each second current collector structure includes a second transport portion and a plurality of second contact portions electrically connected to the second transport portion. In the same second current collector structure, the second transport portion extends along the first direction, and the plurality of second contact portions are spaced apart along the first direction, with the length of the second contact portion along the second direction being greater than its width along the first direction. The plurality of second contact portions pass through the passivation layer and are electrically connected to the second strip-shaped regions, with the second transport portion disposed on the side of the second contact portion facing away from the semiconductor substrate. The first doped semiconductor portion is a P-type semiconductor, the second doped semiconductor portion is an N-type semiconductor, and along the first direction, the distance between two adjacent first contact portions is less than the distance between two adjacent second contact portions, and / or, along the second direction, the length of at least one first contact portion is greater than or equal to the length of at least one second contact portion.

[0041] When the above technical solution is adopted, if the distance between two adjacent first contacts in the first strip region for collecting charge carriers of type P conductivity is small, the transmission distance of charge carriers in the first strip region and along the first direction to the first contact can be shortened, thereby improving the charge carrier collection efficiency of the first collector structure and reducing charge carrier recombination in the first strip region. Conversely, if the distance between two adjacent second contacts in the second strip region for collecting charge carriers of type N conductivity is relatively large, the manufacturing cost of the second contacts can be reduced, and the loss of passivation effect on the second strip region can also be reduced, which is beneficial to improving the passivation effect of the passivation layer on the second strip region and reducing charge carrier recombination.

[0042] Furthermore, the application principle of the beneficial effect of at least one first contact portion having a length greater than or equal to the length of at least one second contact portion can refer to the application principle of the beneficial effect of the spacing between two adjacent first contact portions being less than the spacing between two adjacent second contact portions, as described above, and will not be repeated here.

[0043] As one possible implementation, along the second direction, the width of the first strip region is greater than the width of the second strip region. In this case, it is beneficial to control the area of ​​the PN junction region of the solar cell, which is conducive to the shunting and collection of charge carriers. In addition, when the width of the first strip region is larger, the spacing between two adjacent first contacts is smaller than the spacing between two adjacent second contacts, and / or the length of at least one first contact is greater than or equal to the length of at least one second contact. By reducing the spacing and / or increasing the length, the effective contact area between the first current collector structure and the first strip region can be increased, which is conducive to the timely collection and discharge of holes and reduces the carrier recombination rate.

[0044] As one possible implementation, the semiconductor substrate is an N-type semiconductor. In this configuration, the first doped semiconductor portion has the opposite conductivity type to the semiconductor substrate, and the emitter region of the solar cell includes the first doped semiconductor portion. Based on this, when the width of the first strip region is greater than the width of the second strip region, it is beneficial to increase the overall PN junction region of the cell. However, due to the difference in the transport capability of the P-type semiconductor, the difficulty of carrier collection in the vertical direction differs, requiring a longer first contact portion to achieve better collection. Simultaneously, a smaller spacing helps reduce the lateral transport resistance.

[0045] As one possible implementation, the width of the first transmission section is greater than the width of the second transmission section. This configuration, where the conductivity of the first doped semiconductor section is lower than that of the second doped semiconductor section, reduces the transmission resistance of the first transmission section, allowing the collection of the first and second transmission sections to reach or nearly reach equilibrium, thus improving power generation efficiency. Furthermore, when the width of the first strip region is greater than the width of the second strip region, from a process-acceptable perspective, the width of the first transmission section formed in the first strip region can be larger, further reducing the transmission resistance of the first transmission section.

[0046] As one possible implementation, along the first direction, the spacing between two adjacent first contacts is smaller than the spacing between two adjacent second contacts, and the length of at least one first contact is greater than or equal to the length of at least one second contact. This configuration not only shortens the transmission distance of charge carriers within the first strip region and along the first direction to the first contact by having a relatively small spacing between adjacent first contacts, but also prevents the transmission distance of charge carriers within the first strip region and along the second direction from being too large due to the small length of the first contact, thereby improving the charge carrier collection efficiency of the first collector structure.

[0047] As one possible implementation, the length of at least one first contact portion is greater than the length of at least one second contact portion, and the spacing between two adjacent first contact portions is equal to the spacing between two adjacent second contact portions along the first direction. This configuration allows the first contact portions to have a relatively large length, which is beneficial for improving the collection and extraction efficiency of holes, while reducing the pattern complexity of the screen printing plates used to manufacture the first and second contact portions, thus improving yield. Furthermore, this solution is more suitable for situations where the width of the first strip region is greater than the width of the second strip region, reducing the transport loss of charge carriers within the first strip region and along the second direction to the first contact portion.

[0048] As one possible implementation, the ratio of the sum of the projected areas of all first contacts on the semiconductor substrate in the same first collector structure to the area of ​​the first transmission section is greater than the ratio of the sum of the projected areas of all second contacts on the semiconductor substrate in the same second collector structure to the area of ​​the second transmission section. The application principle of this beneficial effect can be referenced from the previously described principle of the beneficial effect of the spacing between two adjacent first contacts being smaller than the spacing between two adjacent second contacts, and will not be repeated here.

[0049] As one possible implementation, the ratio of the sum of the lengths of all first contacts in the same first collector structure to the length of the first transmission section is greater than the ratio of the sum of the lengths of all second contacts in the same second collector structure to the length of the second transmission section. The application principle of this beneficial effect can be referenced from the previously described principle of the beneficial effect of the spacing between two adjacent first contacts being smaller than the spacing between two adjacent second contacts, and will not be repeated here.

[0050] As one possible implementation, along the second direction, the ratio of the length of the first contact portion to the width of the first strip region electrically connected to the first contact portion is less than or equal to the ratio of the length of the second contact portion to the width of the second strip region electrically connected to the second contact portion. With this configuration, the longer length of the first contact portion is beneficial for shortening the carrier transport distance along the second direction and reducing transport resistance. However, the longer length of the first transport portion can lead to damage to the passivation layer, resulting in passivation loss. Considering that passivation loss has a greater impact on battery efficiency, and given the poor conductivity of the first strip region, the ratio of the length of the first contact portion to the width of the first strip region electrically connected to the first contact portion is set to be relatively small, while the ratio of the length of the second contact portion to the width of the second strip region electrically connected to the second contact portion is set to be relatively large. This increases the number of carriers collected by the first contact portion, allowing the carriers collected by the first and second contact portions to achieve a better matching state, thereby improving power generation efficiency.

[0051] As one possible implementation, along the second direction, the ratio between the length of the first contact portion and the distance between two adjacent first contacts is greater than or equal to the ratio between the length of the second contact portion and the distance between two adjacent second contacts. With this configuration, the conductivity of the P-type first doped semiconductor portion is lower than that of the N-type second doped semiconductor portion. To collect more holes, it is necessary to either increase the length of the first contact portion or decrease the distance between two adjacent first contacts. However, considering that the transmission resistance of carriers to the first contact portion along the second direction has been improved because the length of the first contact portion along the second direction is greater than its width along the first direction, further increasing the length of the first contact portion would cause the first contact portion to extend beyond the first strip region (e.g., through printing). Therefore, by reducing the distance between two adjacent first contacts, the first contact portion is prevented from extending beyond the first strip region. In other words, a larger ratio of the length of the first contact portion to the distance between two adjacent first contacts ensures that more carriers are collected from the P-type first doped semiconductor portion.

[0052] As one possible implementation, the material of at least one first contact portion includes at least one selected from silver, nickel, silver-plated nickel, and titanium. And / or, the material of the first transmission portion includes at least one selected from copper, silver-plated copper, and aluminum. And / or, the thickness of the first transmission portion is greater than the thickness of the first contact portion.

[0053] As one possible implementation, the first contact portion burns through the passivation layer and becomes electrically connected to the first strip region. Alternatively, at least one through-hole contact window is provided on the passivation layer, and the first contact portion becomes electrically connected to the first strip region through the contact window.

[0054] In a second aspect, the present invention provides a photovoltaic module comprising: a plurality of solar cell strings and an encapsulation layer. The solar cell strings include a plurality of solar cells and a plurality of interconnecting structures for connecting the plurality of solar cells in series; or, the solar cell strings include a plurality of solar cells, with adjacent solar cells electrically connected together via a first transmission section. The solar cells are those provided in the first aspect and its various implementations. The encapsulation layer covers the surface of the solar cell strings.

[0055] The beneficial effects of the second aspect and its various implementations in this invention can be found in the analysis of the beneficial effects of the first aspect and its various implementations, and will not be repeated here. Attached Figure Description

[0056] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings: Figure 1 A longitudinal sectional view of the structure of a solar cell provided in an embodiment of the present invention. Figure 1 ; Figure 2 A longitudinal sectional view of the structure of a solar cell provided in an embodiment of the present invention. Figure 2 ; Figure 3 This is a schematic diagram showing the distribution of the first contact portion and the first transmission portion on the first strip portion in a solar cell provided in an embodiment of the present invention. Figure 1 ; Figure 4 This is a schematic diagram illustrating the distribution of the first doped semiconductor portion and the second doped semiconductor portion in a solar cell provided in an embodiment of the present invention. Figure 1 ; Figure 5 This is a schematic diagram illustrating the distribution of the first doped semiconductor portion and the second doped semiconductor portion in a solar cell provided in an embodiment of the present invention. Figure 2 ; Figure 6 This is a schematic diagram illustrating the distribution of the first doped semiconductor portion and the second doped semiconductor portion in a solar cell provided in an embodiment of the present invention. Figure 3 ; Figure 7 This is a schematic diagram showing the distribution of the first and second insulating structures in a solar cell provided in an embodiment of the present invention; Figure 8 A longitudinal sectional view of the structure of a solar cell provided in an embodiment of the present invention. Figure 3 ; Figure 9This is a schematic diagram showing the distribution of the first contact portion in a local area near the second electrical junction portion in a solar cell provided in an embodiment of the present invention. Figure 10 This is a schematic diagram showing the distribution of the first contact portion and the first transmission portion on the first strip portion in a solar cell provided in an embodiment of the present invention. Figure 2 ; Figure 11 A longitudinal sectional view of the structure of a solar cell provided in an embodiment of the present invention. Figure 4 .

[0057] Reference numerals: 11 is a semiconductor substrate, 12 is a first doped semiconductor region, 13 is a first strip region, 14 is a passivation layer, 15 is a first collector structure, 16 is a first transmission region, 17 is a first contact region, 18 is a first electrical junction region, 19 is a second doped semiconductor region, 20 is a second collector structure, 21 is a second electrical junction region, 22 is a first insulating structure, 23 is a second strip region, 24 is a first region, 25 is a second region, 26 is a second terminal line, 27 is a second transmission region, 28 is a second contact region, 29 is a second insulating structure, 30 is a first terminal line, 31 is a first connection region, 32 is a second connection region, 33 is a first interface passivation layer, 34 is a second interface passivation layer, 35 is a first bus electrode, and 36 is a second bus electrode. Detailed Implementation

[0058] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0059] The accompanying drawings illustrate various structural schematic diagrams according to embodiments of the present invention. These drawings are not to scale, and some details have been enlarged for clarity, and some details may have been omitted. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0060] In the context of this invention, when a layer / element is referred to as being "on" another layer / element, the layer / element may be directly on the other layer / element, or there may be an intermediate layer / element between them. Furthermore, if a layer / element is "on" another layer / element in one orientation, then when the orientation is reversed, the layer / element may be "below" the other layer / element. To make the technical problems, technical solutions, and beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0061] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified. "Several" means one or more, unless otherwise explicitly specified.

[0062] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0063] In a first aspect, embodiments of the present invention provide a solar cell. For example... Figures 1 to 3 As shown, the solar cell includes: a semiconductor substrate 11, a first doped semiconductor portion 12, a passivation layer 14, and a plurality of first current collector structures 15. The semiconductor substrate 11 includes a first surface and a second surface facing each other. The first doped semiconductor portion 12 is disposed in a portion of the first surface of the semiconductor substrate 11 or on it. The first doped semiconductor portion 12 includes a plurality of first strip-shaped regions 13 extending along a first direction and spaced apart along a second direction. The first direction and the second direction intersect. The passivation layer 14 is disposed on the side of the first doped semiconductor portion 12 facing away from the semiconductor substrate 11. The plurality of first current collector structures 15 are disposed on the passivation layer 14 corresponding to the first doped semiconductor portion 12. The first current collector structure 15 includes a first transmission portion 16 and a plurality of first contact portions 17 electrically connected to the first transmission portion 16.

[0064] In some embodiments, such as Figure 3As shown, in the same first collector structure 15, a first transmission portion 16 extends along a first direction, and a plurality of first contact portions 17 are spaced apart along the first direction. The length of the first contact portion 17 along a second direction is greater than the width of the first contact portion 17 along the first direction. The plurality of first contact portions 17 pass through the passivation layer 14 and are electrically connected to the first strip region 13. The first transmission portion 16 is disposed on the side of the first contact portion 17 facing away from the semiconductor substrate 11.

[0065] It should be noted that the embodiments of the present invention do not specifically limit the directions referred to by the first direction and the second direction, and can be set according to actual needs. For example, when the first surface of the semiconductor substrate is rectangular, the first direction can be parallel to the extension direction of the long side of the rectangle, and the second direction can be parallel to the extension direction of the short side of the rectangle.

[0066] Furthermore, in the first doped semiconductor section, the width direction of the first strip region is parallel to the second direction, and the length direction of the first strip region is parallel to the first direction. In the first collector structure, the length direction of the first contact portion is parallel to the second direction, and the width direction of the first contact portion is parallel to the first direction; the length direction of the first transmission portion is parallel to the first direction, and the width direction of the first transmission portion is parallel to the second direction.

[0067] Furthermore, in this embodiment of the invention, the first transmission section can be formed on the solar cell. In this case, the first transmission section can serve as an electrode, collecting and transmitting charge carriers. Alternatively, the first transmission section can also be formed on the solar cell and connect two adjacent solar cells in a solar cell string together, serving both as a charge carrier collector and as a current collector. In other words, in this case, the first transmission section can serve as both an electrode and an interconnect structure. In the actual manufacturing process, the first transmission section can be formed by printing, plating (e.g., electroplating, chemical plating, sputtering plating), etc.; or, the first transmission section can also be a conductive wire such as metal, formed on the solar cell by welding or other methods.

[0068] When the above technical solution is adopted, such as Figures 1 to 3As shown, the first current collector structure 15 includes a first contact portion 17 that passes through the passivation layer 14 and is electrically connected to the first strip region 13. When the solar cell is in operation, the first contact portion 17 can collect charge carriers in the first strip region 13 and transmit them to the first transmission portion 16 for outgoing. Since the length of the first contact portion 17 along the second direction is greater than its width along the first direction, even if there are processing errors in the manufacturing equipment for the first contact portion 17 and the first transmission portion 16, causing a deviation in the actual position of the first contact portion 17 or the first transmission portion 16 from its initial design position along the second direction, the larger length of the first contact portion 17 in the second direction can accommodate the positional offset or misalignment of the first contact portion 17 and the first transmission portion 16 along the second direction caused by the aforementioned deviation. This improves the overprinting tolerance and production yield, ensuring that the first transmission portion 16 can be electrically connected to the first contact portion 17, and facilitating the effective collection and outgoing of charge carriers by the first current collector structure 15.

[0069] It should be noted that the overprinting of the first contact portion and the first transmission portion refers to the following in the actual manufacturing process: the first contact portion is formed first, followed by the first transmission portion. The first transmission portion needs to be overprinted onto the first contact portion, and during overprinting, the first transmission portion needs to make contact with the first contact portion to ensure that charge carriers are transported out. The higher the overprinting tolerance, the easier it is for the first transmission portion to make contact with the first contact portion.

[0070] In practical applications, the material and conductivity type of the semiconductor substrate in these embodiments can be set according to actual needs. For example, the semiconductor substrate can be any of the following semiconductor materials: silicon, germanium-silicon, germanium, or gallium arsenide. For example, the semiconductor substrate can be a P-type substrate, an N-type substrate, or an intrinsic substrate.

[0071] As for the first and second surfaces of the semiconductor substrate, their correspondence with the light-facing surface (i.e., the surface directly illuminated by light) and the back surface of the solar cell, respectively, can be determined according to the type of solar cell in the actual application scenario and the requirements for the distribution position of the first doped semiconductor part in the cell.

[0072] For example, in the case of a double-sided contact solar cell, the first doped semiconductor portion can be disposed on the light-facing side of the solar cell. In this case, the first surface of the semiconductor substrate corresponds to the light-facing side of the solar cell, and the second surface of the semiconductor substrate corresponds to the back-facing side of the solar cell. Or, as... Figure 8 and Figure 11 As shown, the first doped semiconductor portion 12 may also be disposed on the back surface side of the solar cell. In this case, the first surface of the semiconductor substrate 11 corresponds to the back surface of the solar cell, and the second surface of the semiconductor substrate 11 corresponds to the light-facing surface of the solar cell.

[0073] For example, in the case of a back-contact solar cell, a first doped semiconductor portion is disposed on the back side of the solar cell. In this case, the first surface of the semiconductor substrate corresponds to the back surface of the solar cell, and the second surface of the semiconductor substrate corresponds to the light-facing surface of the solar cell.

[0074] Regarding the first doped semiconductor region, in terms of its formation location, it can be a doped region directly formed in a partial area of ​​the first surface of the semiconductor substrate using doping processes such as ion implantation or diffusion. Alternatively, as... Figure 1 As shown, the first doped semiconductor portion 12 may also be a doped layer disposed on a portion of the first surface of the semiconductor substrate 11.

[0075] When the first doped semiconductor portion is a doped layer disposed on a partial region of the first surface of the semiconductor substrate, the material of the first doped semiconductor portion may include any one of the following semiconductor materials: silicon, germanium-silicon, germanium, or gallium arsenide. In terms of the arrangement of matter, the crystal phase of the first doped semiconductor portion may be amorphous, microcrystalline, nanocrystalline, single-crystal, or polycrystalline. Optionally, the first doped semiconductor portion may include a doped polycrystalline silicon layer. Alternatively, the material of the first doped semiconductor portion may include at least one of doped amorphous silicon, doped microcrystalline silicon, and doped nanocrystalline silicon.

[0076] Furthermore, when the first doped semiconductor portion is a doped layer disposed on a portion of the first surface of the semiconductor substrate, the first doped semiconductor portion can be directly disposed on the first surface. Or, as... Figure 1 As shown, the solar cell may further include a first interface passivation layer 33 disposed between the first doped semiconductor portion 12 and the first surface to reduce the carrier recombination rate. The material and thickness of the first interface passivation layer 33 can be determined based on the material of the first doped semiconductor portion 12 and actual requirements, and are not specifically limited here. For example, when the material of the first doped semiconductor portion includes doped polycrystalline silicon, the first interface passivation layer is a tunneling oxide layer. As another example, when the material of the first doped semiconductor portion includes at least one of doped amorphous silicon, doped microcrystalline silicon, and doped nanocrystalline silicon, the first interface passivation layer is an intrinsic amorphous silicon layer, an intrinsic microcrystalline silicon layer, an intrinsic nanocrystalline silicon layer, or a mixture of the above three.

[0077] In terms of appearance, such as Figure 4 As shown, the first doped semiconductor section 12 may include only a plurality of first strip regions 13. Alternatively, as... Figure 5 and Figure 6As shown, the first doped semiconductor section 12 may also include a plurality of first strip regions 13 and a plurality of sets of first connection regions. The plurality of sets of first connection regions are spaced apart along a first direction, and each set of first connection regions includes a plurality of first connection regions spaced apart along a second direction. The first connection regions are at least disposed between two adjacent first strip regions 13 and are used to connect two adjacent first strip regions 13 together (or, in addition to the presence of first connection regions located between two adjacent first strip regions 13, there may also be first connection regions disposed outside the outermost first strip region 13 along the second direction; for example...). Figure 5 (The locations shown are near the four corners of the image). The distribution of multiple sets of first connecting areas on the first surface can be set according to actual needs. For example: the first surface includes a first central area and first edge areas located on both sides of the first central area along the second direction; in this case, such as... Figure 6 As shown, multiple sets of first connection regions can be distributed only on the first edge region. Or, as... Figure 5 As shown, the first connecting region can be distributed not only on the first edge region, but also on the first central region.

[0078] In some examples, such as Figure 7 As shown, the solar cell may further include multiple sets of first electrical junctions 18. Multiple sets of first electrical junctions 18 are disposed on a passivation layer 14 corresponding to the first doped semiconductor portion 12. The multiple sets of first electrical junctions 18 are spaced apart along a first direction, and each set of first electrical junctions 18 includes a plurality of first electrical junctions 18 spaced apart along a second direction. Each first electrical junction 18 is electrically connected to a corresponding first current collector structure 15. In this configuration, the first current collector structure 15 is electrically connected to an interconnect structure via the first electrical junctions 18. The interconnect structure is used to connect two adjacent solar cells in series to conduct charge carriers.

[0079] Furthermore, if the first doped semiconductor portion also includes a first connection region, such as Figure 7 As shown, if the first connection area is only distributed on the first edge region, the solar cell may further include multiple first end lines 30. Each first end line 30 is disposed on at least one side of each group of first electrical connections 18 along the second direction, and is electrically connected to the outermost first electrical connection 18 in that group of first electrical connections 18. In this embodiment of the invention, the shape of the first end line 30 is not specifically limited; it may be straight, curved, or broken, or it may be shaped like a harpoon or a U-shape.

[0080] like Figure 5As shown, if the first connection region 31 is distributed not only on the first edge region but also on the first central region, the solar cell may further include a plurality of first bus electrodes 35 spaced apart along a first direction. Each first bus electrode 35 is electrically connected to a plurality of first current collector structures 15.

[0081] In terms of conductivity type, the first doped semiconductor portion can be a P-type semiconductor or an N-type semiconductor; the embodiments of the present invention do not specifically limit the conductivity type of the first doped semiconductor portion.

[0082] In some examples, such as Figure 5 As shown, the solar cell provided in this embodiment of the invention may further include a second doped semiconductor portion 19. The conductivity type of the second doped semiconductor portion 19 is opposite to that of the first doped semiconductor portion 12. For example, when the first doped semiconductor portion 12 is a P-type semiconductor, the second doped semiconductor portion 19 is an N-type semiconductor. Or, for another example, when the first doped semiconductor portion 12 is an N-type semiconductor, the second doped semiconductor portion 19 is a P-type semiconductor. The location of the second doped semiconductor portion 19 on the semiconductor substrate 11 can be determined according to the type of solar cell and actual requirements.

[0083] For example: Figure 8 As shown, in the case of a double-sided contact solar cell, the second doped semiconductor portion 19 is disposed in at least a portion of the second surface of the semiconductor substrate 11. Specifically, in this case, the second doped semiconductor portion 19 may be a doped region disposed in at least a portion of the second surface of the semiconductor substrate 11; or it may be a doped layer disposed in at least a portion of the second surface of the semiconductor substrate 11. The specific range of the second doped semiconductor portion 19 within or on the second surface of the semiconductor substrate 11 can be set according to actual needs.

[0084] For example: Figure 1 As shown, in the case of a back-contact solar cell, the second doped semiconductor portion 19 is disposed in a portion region of or on the first surface of the semiconductor substrate 11. Specifically, in this case, the second doped semiconductor portion 19 may be a doped region disposed in a portion region of the first surface of the semiconductor substrate 11; or it may be a doped layer disposed on a portion region of the first surface of the semiconductor substrate 11. Wherein, when both the first doped semiconductor portion 12 and the second doped semiconductor portion 19 are doped regions disposed in a portion region of the first surface, the first doped semiconductor portion 12 may be spaced apart along a direction parallel to the first surface to reduce the risk of leakage.

[0085] When both the first doped semiconductor portion and the second doped semiconductor portion are doped layers disposed on a portion of the first surface, the first doped semiconductor portion and the second doped semiconductor portion can be distributed at intervals along a direction parallel to the first surface; or, the sidewalls of the first doped semiconductor portion and the second doped semiconductor portion can also abut against each other; or, one of the first doped semiconductor portion and the second doped semiconductor portion can not only be disposed on the semiconductor substrate, but can also extend and cover a portion of the other.

[0086] When one of the first doped semiconductor portion and the second doped semiconductor portion is a doped region disposed in a portion of the first surface region, and the other is a doped layer disposed on the portion of the first surface region, the doped region and the doped layer can be distributed at intervals along a direction parallel to the first surface; or, at least a portion of the sidewalls of the doped region and the doped layer can overlap on the first surface; or, the doped layer can extend and cover a portion of the doped region.

[0087] Furthermore, when the second doped semiconductor portion is a doped layer disposed on the semiconductor substrate, the material of the second doped semiconductor portion can be disposed in accordance with the material disposal principle of the first doped semiconductor portion described above. The material of the second doped semiconductor portion can be the same as or different from the material of the first doped semiconductor portion.

[0088] Furthermore, when the second doped semiconductor portion is a doped layer disposed on the semiconductor substrate, the second doped semiconductor portion can be directly disposed on the semiconductor substrate. Alternatively, as... Figure 1 and Figure 8 As shown, the solar cell may further include a second interface passivation layer 34 disposed between the second doped semiconductor portion 19 and the semiconductor substrate 11 to reduce the carrier recombination rate. The material and thickness of the second interface passivation layer 34 can be determined by referring to the principle of the material and thickness of the first interface passivation layer 33 described above, and will not be repeated here.

[0089] Optionally, the solar cell provided in this embodiment of the invention is a back-contact cell. Furthermore, both the first doped semiconductor portion and the second doped semiconductor portion include a doped polycrystalline silicon layer. The back-contact cell also includes a first interface passivation layer and a second interface passivation layer, and both the first interface passivation layer and the second interface passivation layer are tunneling passivation layers.

[0090] Optionally, the solar cell provided in this embodiment of the invention is a back-contact cell. Furthermore, the first doped semiconductor portion includes a doped polycrystalline silicon layer, and the second doped semiconductor portion includes a doped amorphous silicon layer, a doped microcrystalline silicon layer, a doped nanocrystalline silicon layer, or a mixture of the above three. The second doped semiconductor portion is not only disposed on the semiconductor substrate but also extends and covers a portion of the first doped semiconductor portion. The back-contact cell also includes a first interface passivation layer and a second interface passivation layer, wherein the first interface passivation layer is a tunneling passivation layer, and the second interface passivation layer includes an intrinsic amorphous silicon layer, an intrinsic microcrystalline silicon layer, an intrinsic nanocrystalline silicon layer, or a mixture of the above three.

[0091] Optionally, the solar cell provided in this embodiment of the invention is a double-sided contact cell. Furthermore, the first doped semiconductor portion includes a doped polycrystalline silicon layer, and the solar cell also includes a first interface passivation layer, which is a tunneling passivation layer. The second doped semiconductor portion can be disposed within the second surface of the semiconductor substrate; or the second doped semiconductor portion can also be disposed on the second surface of the semiconductor substrate. Wherein, when the second doped semiconductor portion is disposed on the second surface of the semiconductor substrate, the second doped semiconductor portion can include a doped polycrystalline silicon layer. In this case, if the solar cell also includes a second interface passivation layer, the second interface passivation layer is a tunneling passivation layer; or, the second doped semiconductor portion can also be a doped amorphous silicon layer, a doped microcrystalline silicon layer, a doped nanocrystalline silicon layer, or a mixture of the above three layers. In this case, if the solar cell also includes a second interface passivation layer, the second interface passivation layer is an intrinsic amorphous silicon layer, an intrinsic microcrystalline silicon layer, an intrinsic nanocrystalline silicon layer, or a mixture of the above three layers.

[0092] In terms of appearance, such as Figures 4 to 6 As shown, the second doped semiconductor portion 19 includes a plurality of second strip-shaped regions 23 extending along a first direction and spaced apart along a second direction. Specifically, as... Figure 4 As shown, the second doped semiconductor section 19 may include only a plurality of second strip regions 23. Alternatively, as... Figure 5 and Figure 6 As shown, the second doped semiconductor section 19 may also include a plurality of second strip regions 23 and a plurality of sets of second connection regions 32. The plurality of sets of second connection regions 32 are spaced apart along a first direction, and each set of second connection regions 32 includes a plurality of second connection regions 32 spaced apart along a second direction. The second connection regions 32 are at least disposed between two adjacent second strip regions 23 and are used to connect two adjacent second strip regions 23 together (or, in addition to second connection regions 32 located between two adjacent second strip regions 23, second connection regions 32 may also be disposed outside the outermost second strip region 23 along the second direction; for example...). Figure 6The two uppermost second connection areas 32 are located near the top of the image, and the two lowermost second connection areas 32 are located near the bottom of the image. Along the second direction, the distribution of the multiple sets of second connection areas 32 on the first or second surface can be based on the distribution of the first connection areas 32 on the first surface as described above. For example: Figure 6 As shown, when multiple sets of first connection areas 32 are only distributed on the first edge region, if the solar cell is a back contact cell, then multiple sets of second connection areas 32 are also only distributed on the first edge region of the first surface; if the solar cell is a double-sided contact cell, then multiple sets of second connection areas 32 are only distributed on the second edge region of the second surface.

[0093] For example: Figure 5 As shown, when the first connection area 31 is distributed not only on the first edge region but also on the first central region, if the solar cell is a back-contact cell, then multiple sets of second connection areas 32 are also distributed not only on the first edge region of the first surface but also on the first central region of the first surface; if the solar cell is a double-sided contact cell, then multiple sets of second connection areas 32 are distributed not only on the second edge region of the second surface but also on the second central region of the second surface. In the second surface, the second edge region is located on both sides of the second central region along the second direction.

[0094] In practical applications, the widths of the first stripe region in the first doped semiconductor section and the second stripe region in the second doped semiconductor section can be set according to their conductivity types and actual requirements. Specifically, along the second direction, the width of the first stripe region can be equal to the width of the second stripe region. Alternatively, the width of the first stripe region can also be greater than the width of the second stripe region. In this case, it is advantageous to control the formation range of the first and second doped semiconductor sections on the semiconductor substrate by adjusting the widths of the first and second stripe regions, thereby controlling the PN junction area of ​​the solar cell and facilitating carrier shunting and collection. Furthermore, when the conductivity type of the first doped semiconductor section is opposite to that of the semiconductor substrate, if the width of the first stripe region is greater than the width of the second stripe region, it is advantageous to increase the PN junction area of ​​the cell, thereby improving carrier separation and collection efficiency. For example, the first doped semiconductor section and the semiconductor substrate are N-type semiconductors, the second doped semiconductor section is a P-type semiconductor, and the width of the first stripe region is greater than the width of the second stripe region. In this case, along the second direction, the width of the first strip region can be greater than or equal to 100 μm and less than or equal to 700 μm; the width of the second strip region can be greater than or equal to 80 μm and less than or equal to 500 μm.

[0095] It should be noted that, in the case of a back-contact solar cell, the second strip-shaped region included in the second doped semiconductor portion and the first strip-shaped region included in the first doped semiconductor portion are alternately distributed along the second direction. Furthermore, when the first doped semiconductor portion also includes multiple sets of first connection regions, and the second doped semiconductor portion also includes multiple sets of second connection regions, the multiple sets of first connection regions and the multiple sets of second connection regions are alternately distributed along the first direction. Moreover, the first strip-shaped region is disconnected at the intersection of its extension line and the second connection region, and the second strip-shaped region is disconnected at the intersection of its extension line and the first connection region to prevent short circuits and reduce the risk of leakage.

[0096] Furthermore, in cases where the solar cell also includes a second doped semiconductor section, such as Figures 4 to 6 As shown, the solar cell may also include multiple second current collector structures 20. Each second current collector structure 20 is electrically connected to the second strip region 23 through the passivation layer 14 to extract the charge carriers collected by the second doped semiconductor portion 19. The structure of the second current collector structure 20 may be the same as or different from the structure of the first current collector structure 15.

[0097] Wherein, when the structure of the second collector structure is the same as the structure of the first collector structure, it means: such as Figure 1 and Figure 4 As shown, the second collector structure 20 includes a second transmission section 27 and a plurality of second contacts 28 electrically connected to the second transmission section 27. In the same second collector structure 20, the second transmission section 27 extends along a first direction, and the plurality of second contacts 28 are spaced apart along the first direction. The length of the second contacts 28 along the second direction is greater than the width of the second contacts 28 along the first direction. The plurality of second contacts 28 pass through the passivation layer 14 and are electrically connected to the second strip region 23. The second transmission section 27 is disposed on the side of the second contacts 28 facing away from the semiconductor substrate 11. In this case, information such as the size, material, and relative positional relationship of the second contacts 28 and the second transmission section 27 in the second collector structure 20 can be found in the description of the size, material, and relative positional relationship of the first contacts 17 and the first transmission section 16 in the first collector structure 15 throughout the text.

[0098] In some examples, such as Figure 7As shown, the solar cell may further include multiple sets of second electrical junctions 21. Multiple sets of second electrical junctions 21 are disposed on the passivation layer 14 corresponding to the second doped semiconductor portion 19. The multiple sets of second electrical junctions 21 are spaced apart along a first direction, and each set of second electrical junctions 21 includes multiple second electrical junctions 21 spaced apart along a second direction. Each second electrical junction 21 is electrically connected to a corresponding second current collector structure 20. In this configuration, the second current collector structure 20 is electrically connected to an interconnect structure via the second electrical junctions 21. The interconnect structure is used to connect two adjacent solar cells in series to conduct charge carriers. In the case of a back-contact solar cell, the multiple sets of second electrical junctions 21 and the multiple sets of first electrical junctions 18 are alternately spaced along the first direction.

[0099] Furthermore, if the second doped semiconductor portion also includes a second connection region, such as Figure 7 As shown, if the second connection area is distributed only on the first edge region (or only on the second edge region), the solar cell may further include a plurality of second end lines 26. Each second end line 26 is disposed on at least one side of each group of second electrical connections 21 along the second direction, and is electrically connected to the outermost second electrical connection 21 in that group of second electrical connections 21. The morphology of the second end line 26 in this embodiment can be referenced to the first end line 30. In the case of a back-contact solar cell, the plurality of second end lines 26 and the plurality of first end lines 30 are alternately distributed along the first direction.

[0100] like Figure 5 As shown, if the second connection region 32 is distributed not only on the first edge region (or not only on the second edge region), but also on the first central region (or also on the second central region), the solar cell may further include a plurality of second bus electrodes 36 spaced apart along the first direction. Each second bus electrode 36 is electrically connected to a plurality of second current collector structures 20. Wherein, in the case of a back-contact solar cell, the plurality of second bus electrodes 36 and the plurality of first bus electrodes 35 are alternately spaced along the first direction.

[0101] Furthermore, in the case of a back-contact solar cell, such as Figure 7 As shown, the solar cell may further include a first insulating structure 22 and / or a second insulating structure 29. For example... Figure 7As shown, multiple first insulating structures 22 cover the first current collector structure 15, and the first insulating structures 22 and the second electrical connection portion 21 are alternately distributed along the second direction. Multiple second insulating structures 29 cover the second current collector structure 20, and the second insulating structures 29 and the first electrical connection portion 18 are alternately distributed along the second direction to prevent the interconnect structure from overlapping with the first current collector structure 15 or the second current collector structure 20 with opposite polarity, thus preventing short circuits and improving the electrical reliability of the solar cell.

[0102] For the passivation layer, the passivation layer covers the side of the first doped semiconductor portion that is away from the semiconductor substrate. Alternatively, when the solar cell also includes a second doped semiconductor portion, and the second doped semiconductor portion is also disposed within or on the first surface of the semiconductor substrate, the passivation layer may also cover the side of the second doped semiconductor portion that is away from the semiconductor substrate.

[0103] The material and thickness of the passivation layer can be set according to actual needs. For example, the material of the passivation layer can include any material with passivation function such as silicon oxide, silicon nitride, or aluminum oxide.

[0104] For multiple first collector structures, in terms of materials, the material of the first collector structure can include any kind of conductive material, and the specific material of the first collector structure can be set according to actual needs.

[0105] For example, the material of at least one first contact portion may include at least one of silver, nickel, silver-plated nickel, and titanium. With this configuration, when the first contact portion is made of nickel or titanium, it can form a low-resistance semiconductor with the first strip region, which is beneficial for improving the contact performance between the first collector structure and the first strip region. Furthermore, nickel and titanium materials have good diffusion-blocking properties, preventing the material of the first transport portion from diffusing into the first strip region and causing recombination losses. Simultaneously, the contact layer formed by the reaction of nickel and titanium materials with the first strip region is chemically bonded, resulting in stronger adhesion and preventing the first collector structure from detaching. When the first contact portion is made of silver, the contact resistance between the first contact portion and the doped conductive portion can be reduced, reducing transport losses. Additionally, it helps to give the first contact portion excellent chemical inertness and improve oxidation resistance.

[0106] It should be noted that the definition of "at least one" is explained below using at least one first contact portion as an example. At least one first contact portion can refer to only one first contact portion, or it can refer to multiple first contact portions. Specifically, when at least one first contact portion refers to multiple first contact portions, the multiple first contact portions can be some of the first contact portions included in the solar cell, or it can be all of the first contact portions included in the solar cell. The meaning of "at least one" throughout this text can refer to this explanation.

[0107] For example, the material of the first transmission section may include at least one of copper, silver-clad copper, and aluminum. This arrangement helps to reduce the manufacturing cost of the first collector structure.

[0108] In the case where the solar cell also includes a first electrical junction portion, the material of the first electrical junction portion can be the same as the material of the first transmission portion; in this case, the first electrical junction portion can be integrally formed with the first transmission portion, that is, the two can be formed simultaneously; or, in this case, the first transmission portion can also be manufactured separately from the first electrical junction portion.

[0109] Alternatively, the material of the first electrical connection can be different from the material of the first transmission part. For example, the material of the first electrical connection is silver, and the material of the first transmission part is copper or aluminum.

[0110] In practical applications, the first contact portion can burn through the passivation layer to electrically connect with the first strip region. In this case, the material of the first contact portion can be, for example, silver paste. Alternatively, at least one through-hole contact window can be formed on the passivation layer by means of laser etching or chemical etching. The first contact portion can be electrically connected to the first strip region through the contact window. In this case, the material of the first contact portion can be, for example, nickel or titanium.

[0111] Secondly, the thickness of the first transmission part can be greater than the thickness of the first contact part, so as to reduce the line resistance of the first transmission part and reduce transmission loss.

[0112] Alternatively, the thickness of the first transmission part can be equal to or less than the thickness of the first contact part. A smaller thickness of the first transmission part can reduce the cost of producing the first transmission part.

[0113] From a design dimension perspective, the length of the first contact portion affects the overprinting between the first contact portion and the first transmission portion, as well as the carrier collection efficiency. Therefore, the length of the first contact portion can be determined according to the actual requirements of the application scenario, such as the overprinting tolerance between the first contact portion and the first transmission portion, the carrier collection efficiency, and the manufacturing cost.

[0114] For example, such as Figure 4As shown, along the second direction, the length of at least one first contact portion 17 is greater than or equal to 30 μm, and less than or equal to 75% of the width of the first strip-shaped region 13 electrically connected to the first contact portion 17. For example, along the second direction, the length of at least one first contact portion can be 30 μm, 40 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 80 μm, 100 μm, 120 μm, 150 μm, 180 μm, 200 μm, 220 μm, 240 μm, or 260 μm, etc. This design prevents the contact resistance from being too high due to a small contact area between the first contact and the first transmission part caused by an excessively small length of the first contact, thus improving the contact performance between them. Simultaneously, it prevents the transmission resistance of charge carriers along the second direction from being too high due to an excessively small length of the first contact, reducing charge carrier recombination. Furthermore, it improves the overprinting tolerance of the first contact and the first transmission part, ensuring electrical connection between them during manufacturing, which is beneficial for charge carrier collection. Moreover, it prevents the manufacturing equipment for printing the first contact (or, in the case where the first contact is electrically connected to the first strip region through a contact window in the passivation layer, the laser or other etching equipment for creating the contact window) from having excessively small lengths, thus reducing manufacturing difficulty. Secondly, it prevents the consumption of electrode material for manufacturing the first contact from being too large, thus controlling manufacturing costs and reducing damage to the passivation layer caused by an excessively large first contact, resulting in a better passivation effect.

[0115] Optionally, along the second direction, the length of at least one first contact portion is greater than or equal to 50 μm.

[0116] For example, such as Figure 4 As shown, in at least one first collector structure 15, the ratio of the width of the first transmission portion 16 to the length of at least one first contact portion 17 is greater than or equal to 10% and less than or equal to 200%. For example, in at least one first collector structure, the ratio of the width of the first transmission portion to the length of at least one first contact portion can be 10%, 20%, 30%, 50%, 60%, 80%, 100%, 120%, 130%, 150%, 160%, 180%, or 200%, etc. Regarding the beneficial effects of such a setting, the ratio of the width of the first transmission portion to the length of at least one first contact portion being within the above range can be referenced to the beneficial effects of the length of at least one first contact portion being within the above range described above. Secondly, it can also prevent the width of the first transmission portion from being too large, which is beneficial for controlling manufacturing costs; and it can also prevent the transmission resistance from being too large due to the width of the first transmission portion being too small, which is beneficial for reducing transmission loss.

[0117] Optionally, in at least one first collector structure, the ratio of the width of the first transmission section to the length of at least one first contact section is greater than or equal to 10% and less than or equal to 100%. This configuration not only resolves the misalignment between the first contact section and the first transmission section but also further reduces the width of the first transmission section, thereby lowering its cost.

[0118] It is worth noting that even with the improvement in the misregistration problem of the first contact portion and the first transmission portion, the matching of factors such as carrier collection effect, passivation damage, and cost still needs to be considered when designing the first contact portion and the first transmission portion. Therefore, this application designs at least one of the first contact portions with a length greater than or equal to 30 μm along the second direction. This can prevent the transmission resistance of carriers to the first contact portion along the second direction from being too small, which would reduce the power generation efficiency. Furthermore, when the first contact portion is formed by printing, a first contact portion with too small a length will result in insufficient ink flow on the printing screen, leading to less ink paste for printing the first contact portion. Less ink paste will result in the inability to effectively penetrate the passivation layer to form an effective contact, which is also beneficial to improving the misregistration tolerance of the first contact portion and the first transmission portion and facilitating carrier collection. Secondly, setting the length of the first contact portion to be less than or equal to 75% of the width of the first strip region ensures effective collection and prevents excessive offset of the first contact portion due to issues such as stencil deformation or positioning misalignment after mass printing. This could lead to printing outside the first strip region, further causing other contact defects or passivation losses, thus reducing efficiency and yield. Furthermore, it prevents excessive consumption of electrode material for manufacturing the first contact portion due to its excessive length, thus controlling manufacturing costs and reducing passivation layer loss, resulting in better passivation performance. Based on this, when controlling the length of the first contact portion to minimize the impact of carrier transport and passivation losses on efficiency, the ratio of the width of the first transmission portion to the length of the first contact portion is set to be greater than or equal to 10% and less than or equal to 200%. This prevents the width of the first transmission portion from becoming too large, further controlling manufacturing costs, and also prevents excessive transmission resistance due to an excessively small width, thus avoiding transmission losses.

[0119] For example, along the second direction, the length of at least one first contact portion can be greater than or equal to 10% of the width of the first strip region electrically connected to the first contact portion. This configuration further reduces the transmission resistance of charge carriers along the second direction to the first contact portion, improving power generation efficiency; it also further reduces the misalignment between the first contact portion and the first transmission portion, reducing process difficulty; furthermore, setting the length of the first contact portion to be greater than or equal to 10% of the width of the first strip region electrically connected to the first contact portion increases the length of the first contact portion, thus increasing ink leakage during the printing process, resulting in a better linear shape of the first contact portion, and allowing for more effective contact between the first contact portion and the first doped semiconductor portion. For example, the length of the first contact portion can be greater than 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, etc., of the width of the first strip region electrically connected to the first contact portion.

[0120] For example, the length of at least one first contact portion is greater than or equal to 50 μm and less than or equal to 150 μm. For instance, the length of at least one first contact portion can be 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 120 μm, 140 μm, or 150 μm, etc. The beneficial effects in this case can be referred to the aforementioned beneficial effects of preventing the length of at least one first contact portion from being too large or too small, and will not be repeated here.

[0121] For example, when the solar cell further includes multiple sets of first electrical junctions, the first electrical junctions may overlap with at least one first contact. With this configuration, when the first electrical junction overlaps with at least one first contact, the charge carriers collected by the first contact can be directly transported into the first electrical junction along the thickness direction of the semiconductor substrate, which helps to shorten the carrier transport path and reduce transport losses. Furthermore, the increased surface roughness of the first electrical junction improves the welding effect. Specifically, in this case, the extent to which the first electrical junction covers the first contact along the second direction can be set according to actual needs. The first electrical junction may only cover at least a portion of the first contact below it along the second direction; or, the first electrical junction may completely cover the first contact below it. Additionally, the spacing between two adjacent first contacts below the first electrical junction along the first direction may be the same as, or different from, the spacing between two adjacent first contacts on either side of the first electrical junction along the first direction.

[0122] For example, along the second direction, the width of at least one first electrical junction can be greater than or equal to the length of the first contact portion. This arrangement prevents excessive manufacturing costs due to an excessively long first contact portion; secondly, it prevents reduced bonding strength between the first electrical junction and the interconnect structure used to connect adjacent solar cells in series, thus reducing the risk of interconnect structure detachment. Furthermore, it allows the first electrical junction to be positioned directly above at least a portion of the first contact portion, thereby shortening the carrier transport path and reducing transport losses.

[0123] For example, along the first direction, the width of at least one first contact portion is greater than or equal to 8 μm and less than or equal to 30 μm. For instance, the width of at least one first contact portion can be 8 μm, 10 μm, 12 μm, 15 μm, 18 μm, 20 μm, 22 μm, 24 μm, 26 μm, 28 μm, or 30 μm, etc. This configuration prevents the manufacturing difficulty of the first contact portion from being too small, such as making the manufacturing of the printing screen used to print the first contact portion too difficult, thus reducing manufacturing precision requirements. Furthermore, it also prevents the material consumption of the first contact portion from being too large, thus reducing manufacturing costs; simultaneously, it reduces the loss of the passivation layer caused by manufacturing the first contact portion, resulting in a better passivation effect.

[0124] For example, the ratio between the length of at least one first contact portion and its width is greater than or equal to 1.5 and less than or equal to 20. The application principle of the beneficial effect in this case can be referred to the application principle of the beneficial effect of preventing the length of the first contact portion from being too large or too small, and preventing the width of the first contact portion from being too large or too small, as described above, and will not be repeated here.

[0125] It should be noted that, within the same first collector structure, the lengths of the multiple first contacts can be the same or different. Additionally, within the same first collector structure, the widths of the multiple first contacts can be the same or different.

[0126] In the same first collector structure, the two ends of multiple first contacts along the second direction can be flush or staggered.

[0127] Optional, such as Figure 4As shown, in the same first collector structure 15, the lengths of multiple first contacts 17 are the same; and / or, the two ends of the multiple first contacts 17 along the second direction are respectively flush. This arrangement is beneficial because each first contact 17 has a larger length, thereby having a higher carrier collection capacity, which is conducive to the timely discharge of carriers collected in each region within the first strip region 13. In addition, when the two ends of the multiple first contacts 17 along the second direction are respectively flush, it is beneficial because each first contact 17 has at least a portion of its area that can be electrically connected to the first transmission section 16. This prevents the first transmission section 16 from being unable to be electrically connected to a portion of the first contacts 17, or from having a small electrical connection area, due to manufacturing errors and the misalignment of the same side ends of different first contacts 17. This improves the overprinting tolerance between each first contact 17 and the first transmission section 16; at the same time, it reduces the transmission resistance of carriers from the first contact 17 to the first transmission section 16, thus reducing losses.

[0128] Among them, Figure 4 In the structure shown, the first direction refers to the lateral extension direction in the figure, and the second direction refers to the longitudinal extension direction in the figure. Based on this, in the same first collector structure 15, the two ends of the plurality of first contact portions 17 being flush along the second direction means that the line connecting the uppermost point (or straight line) of the top of the plurality of first contact portions 17 belonging to the same first collector structure 15 is parallel to the first direction, and the line connecting the lowermost point (or straight line) of the bottom of the plurality of first contact portions 17 is parallel to the first direction.

[0129] Alternatively, in the same first collector structure, the two ends of multiple first contacts along the second direction being flush can also mean that, along the second direction, the ends of multiple first contacts belonging to the same first collector structure are spaced at the same distance from the edge of the first strip area on the same side.

[0130] In addition, such as Figure 4 As shown in this embodiment of the invention, in the same first collector structure 15, the first transmission section 16 can be electrically connected to a row of first contact sections 17. The centerlines of multiple first contact sections 17 extending along the first direction in the same row of first contact sections 17 coincide. In other words, the centerlines of all first contact sections 17 extending along the first direction in the first collector structure 15 can coincide, and the first collector structure 15 includes only one row of first contact sections 17. The application principle of the beneficial effect in this case can refer to the application principle of the beneficial effect of multiple first contact sections 17 having their two ends aligned along the second direction as described above, and will not be repeated here.

[0131] Alternatively, within the same first collector structure, at least one centerline extending along the first direction of the first contact portion may exist, staggered from the centerlines extending along the first direction of the other first contacts portions; in this case, the first collector structure may include at least two rows of first contacts. In this scenario, the first transmission portion may be electrically connected to only one row of first contacts, or it may be electrically connected to multiple rows of first contacts simultaneously.

[0132] As for the same first collector structure, the spacing between two adjacent first contacts can be set according to the actual needs of carrier collection efficiency and manufacturing cost in the actual application scenario.

[0133] In at least one first collector structure, the spacing between two adjacent first contacts can be greater than or equal to the length of the first contact. Because the length of the first contact along the second direction is greater than its width along the first direction, the first contact and the first transmission part can meet a larger overprinting tolerance, giving the first transmission part more room for cost reduction. However, this leads to increased mold opening losses. Therefore, designing the spacing between two adjacent first contacts to be greater than or equal to the length of the first contact can prevent the first collector structure from having too many first contacts due to the spacing between two adjacent first contacts being too small, thereby preventing the manufacturing cost of the first contacts from being too high. Furthermore, it can also reduce the loss of the passivation layer caused by manufacturing too many first contacts, which is beneficial for the passivation layer to have a good passivation effect.

[0134] Of course, it is also possible that in at least one first collector structure, the length of at least one first contact portion is greater than the distance between two adjacent first contacts. With this configuration, when the number of first collector structures is small and the width of the first strip region is large, the length of the first contact portion can be set to be larger than the distance between two adjacent first contacts to ensure collection. Furthermore, if the material cost of the first contact portion is acceptable, the length of the first contact portion can also be increased to reduce the carrier transport resistance.

[0135] For example, in at least one first collector structure, the ratio of the length of the first contact portion to the distance between two adjacent first contacts is greater than or equal to 15% and less than or equal to 100%. For instance, the ratio of the length of the first contact portion to the distance between two adjacent first contacts can be 15%, 20%, 25%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 90%, or 100%, etc. This setting prevents the length of the first contact portion from being too small and / or the distance between two adjacent first contacts from being too large due to an excessively small ratio. This improves the overlay tolerance between the first contact portion and the first transmission portion, while reducing the transmission loss of charge carriers located on both sides of the first contact portion along the second direction to the first contact portion, and also reducing the transmission loss of charge carriers located on both sides of the first contact portion along the first direction to the first contact portion. Furthermore, this design can prevent excessive length of the first contact portion and / or excessive spacing between adjacent first contacts due to an excessively large ratio, thereby reducing the manufacturing cost of the first contact portion and the probability that at least one end of the first contact portion along the second direction is printed outside the first strip area, reducing the risk of leakage current due to direct contact between the first contact portion and the semiconductor substrate. It also helps control the number of first contacts included in the first collector structure, reducing passivation layer loss caused by manufacturing too many first contacts, and promoting a good passivation effect. Additionally, it facilitates matching the width, length, and spacing of the first contacts, ensuring that the contact resistance of the first contact portion and the first transmission portion, as well as the passivation performance of the passivation layer, are optimal.

[0136] For example, in at least one first collector structure, the distance between two adjacent first contacts is greater than or equal to 50 μm and less than or equal to 300 μm. For instance, the distance between two adjacent first contacts can be 50 μm, 80 μm, 100 μm, 120 μm, 150 μm, 180 μm, 200 μm, 220 μm, 260 μm, 280 μm, or 300 μm, etc. The beneficial effect in this case can be referred to the previously described beneficial effect of preventing the distance between two adjacent first contacts from being too large or too small, and will not be repeated here.

[0137] In practical applications, the spacing between any two adjacent first contacts in the same first collector structure can be the same. Alternatively, there may be at least one pair of adjacent first contacts with a different spacing than the other pairs of adjacent first contacts. In this case, the specific pairs of adjacent first contacts with different spacings can be set according to actual needs.

[0138] For example, such as Figure 7 and Figure 9As shown, in a solar cell that also includes a second doped semiconductor section 19, a plurality of second current collector structures 20, and a plurality of sets of second electrical junctions 21, and where both the second doped semiconductor section 19 and the first doped semiconductor section are disposed on the first surface, in at least one first current collector structure 15, the first transmission section 16 is disconnected at the intersection with the extension line of each set of second electrical junctions 21, and in this first current collector structure 15, the spacing between two adjacent first contact portions 17 near the disconnection point of the first transmission section 16 is different from the spacing between two adjacent first contact portions 17 away from the disconnection point of the first transmission section 16. This arrangement, where the first transmission section 16 is disconnected at the intersection with the extension line of each set of second electrical junctions 21, prevents short circuits. Furthermore, in this first collector structure 15, the spacing between two adjacent first contact portions 17 near the disconnection point of the first transmission section 16 is different from the spacing between two adjacent first contact portions 17 away from the disconnection point of the first transmission section 16. In this case, it is understandable that the location near the disconnection point of the first transmission section 16 needs to consider the short circuit problem between interconnect structures with opposite polarities, as well as the problems of carrier collection and passivation damage. On the other hand, the location away from the disconnection point of the first transmission section 16 only needs to consider the problems of carrier collection and passivation damage. Based on the different problems considered in the above two types of locations, an adaptive design is made for the spacing of the first contact portions in these two types of locations, so that the spacing between two adjacent first contact portions 17 near the disconnection point of the first transmission section 16 and the spacing between two adjacent first contact portions 17 away from the disconnection point of the first transmission section 16 are both within a suitable range. This ensures that the location near the disconnection point of the first transmission section 16 has a lower leakage risk, while also ensuring that both types of locations have a higher passivation effect and a higher carrier collection efficiency, thereby improving product yield and efficiency. Specifically, in this case, the distance between two adjacent first contact portions 17 near the break point of the first transmission section 16 in the first collector structure 15 may be smaller than the distance between two adjacent first contact portions 17 away from the break point of the first transmission section 16. This can more effectively prevent short circuits caused by the overlap between the heterogeneous interconnect structure and the first contact portion. Alternatively, the distance between two adjacent first contact portions 17 near the break point of the first transmission section 16 in the first collector structure 15 may be larger than the distance between two adjacent first contact portions 17 away from the break point of the first transmission section 16.

[0139] Of course, in this first collector structure, the spacing between two adjacent first contact portions near the point where the first transmission section is disconnected can also be the same as the spacing between two adjacent first contact portions far from the point where the first transmission section is disconnected.

[0140] For example, such as Figure 7As shown, in the same group of second electrical connection portions 21, the area between two adjacent second electrical connection portions 21 is defined as the first region 24. The area between two adjacent groups of second electrical connection portions 21 is defined as the second region 25. The spacing between two first contact portions 17 located in the first region 24 and adjacent along the first direction can be different from the spacing between two first contact portions 17 located in the second region 25 and adjacent along the first direction. With this arrangement, the spacing between two adjacent first contact portions 17 near the break point can be reasonably set according to the distance at which the first transmission portion 16 is disconnected. Understandably, the first region needs to consider not only the collection and passivation damage of charge carriers, but also the setting of the first insulation structure and the short circuit problem of interconnection structures with opposite polarities. However, the second region only needs to consider the collection and passivation damage of charge carriers. Based on the different problems considered in the first and second regions, the spacing between the two first contact portions 17 located in the first region 24 and adjacent along the first direction, and the spacing between the two first contact portions 17 located in the second region 25 and adjacent along the first direction are set differently, so that both the first and second regions can meet the corresponding requirements. This prevents the spacing between the two adjacent first contact portions 17 near the boundary of the first region 24 and the second region 25 from being too small, which would result in high manufacturing costs and poor passivation effect of the passivation layer 14 near the boundary. It also prevents the spacing between the two adjacent first contact portions 17 near the boundary of the first region 24 and the second region 25 from being too large, which would result in high carrier transport loss near the boundary and reduce carrier recombination. Specifically, in this case, the distance between two first contact portions 17 located in the first region 24 and adjacent along the first direction can be greater than the distance between two first contact portions 17 located in the second region 25 and adjacent along the first direction; or, the distance between two first contact portions 17 located in the first region 24 and adjacent along the first direction can be less than the distance between two first contact portions 17 located in the second region 25 and adjacent along the first direction.

[0141] Of course, in at least one first collector structure, the spacing between two first contacts located in the first region and adjacent along the first direction can be the same as the spacing between two first contacts located in the second region and adjacent along the first direction.

[0142] In addition, such as Figure 4 As shown, the solar cell also includes a second doped semiconductor section 19 and a plurality of second current collector structures 20. Furthermore, when the second current collector structure 20 includes a second transmission section 27 and a plurality of second contact sections 28, the relationship between the spacing between two adjacent first contact sections 17 and the spacing between two adjacent second contact sections 28, as well as the relationship between the length of the first contact section 17 and the length of the second contact section 28, can be set according to the conductivity type of the first doped semiconductor section 12 and the second doped semiconductor section 19, and actual requirements.

[0143] For example, when the first doped semiconductor portion is a P-type semiconductor and the second doped semiconductor portion is an N-type semiconductor, the distance between two adjacent first contacts along the first direction can be less than the distance between two adjacent second contacts, and / or, along the second direction, the length of at least one first contact can be greater than or equal to the length of at least one second contact. With this configuration, the conductivity of the P-type semiconductor is relatively poor compared to the N-type semiconductor. Therefore, when the distance between two adjacent first contacts used to collect carriers in the first strip region with P-type conductivity is small, the transmission distance of carriers within the first strip region and along the first direction to the first contact can be shortened, improving the carrier collection efficiency of the first collector structure and reducing carrier recombination in the first strip region. Conversely, the distance between two adjacent second contacts used to collect carriers in the second strip region with N-type conductivity is relatively large, which can reduce the manufacturing cost of the second contacts and also reduce the loss of passivation effect on the second strip region, thus improving the passivation effect of the passivation layer on the second strip region and reducing carrier recombination. Furthermore, the beneficial effect of having at least one first contact portion longer than at least one second contact portion can be referred to in light of the beneficial effect of having a spacing between two adjacent first contact portions smaller than a spacing between two adjacent second contact portions, as described above, and will not be repeated here.

[0144] For example, when the width of the first strip region is greater than the width of the second strip region, the spacing between two adjacent first contact portions along the first direction can be less than the spacing between two adjacent second contact portions, and / or, along the second direction, the length of at least one first contact portion can be greater than or equal to the length of at least one second contact portion. This configuration increases the effective contact area between the first collector structure and the first strip region by reducing the spacing and / or increasing the length, facilitating timely collection and discharge of holes and reducing the carrier recombination rate. Furthermore, when the conductivity type of the first doped semiconductor portion is P-type, the conductivity of the P-type doped semiconductor portion is relatively poor; increasing the width of the first strip region helps to increase the contact area between the first doped semiconductor portion and the first collector structure, which is beneficial for carrier collection.

[0145] For example, the width of the first strip region is greater than the width of the second strip region, and the conductivity type of the first doped semiconductor portion is opposite to that of the semiconductor substrate. With this configuration, the first doped semiconductor portion and the semiconductor substrate can form a PN junction. Increasing the width of the first strip region helps to increase the junction area of ​​the PN junction, which is beneficial for the shunting and collection of charge carriers.

[0146] Optionally, when the first doped semiconductor portion is a P-type semiconductor and the second doped semiconductor portion is an N-type semiconductor, along the first direction, the spacing between two adjacent first contacts is smaller than the spacing between two adjacent second contacts, and the length of at least one first contact is greater than or equal to the length of at least one second contact. This configuration not only shortens the transmission distance of charge carriers within the first strip region and along the first direction to the first contact by having a relatively small spacing between adjacent first contacts, but also prevents the transmission distance of charge carriers within the first strip region and along the second direction from being too large due to the small length of the first contact, thereby improving the charge carrier collection efficiency of the first collector structure.

[0147] Optionally, when the first doped semiconductor portion is a P-type semiconductor and the second doped semiconductor portion is an N-type semiconductor, the length of at least one first contact portion is greater than the length of at least one second contact portion, and the spacing between two adjacent first contacts is equal to the spacing between two adjacent second contacts along the first direction. This configuration allows the first contacts to have a relatively large length, reducing the hole transport distance and improving hole collection and extraction efficiency. Simultaneously, it reduces the pattern complexity of the screen printing stencil for manufacturing the first and second contacts, thus improving yield. Furthermore, this solution is more suitable when the width of the first strip region is greater than the width of the second strip region, reducing carrier transport losses within the first strip region and along the second direction to the first contact portion.

[0148] For example, when the first doped semiconductor portion is a P-type semiconductor and the second doped semiconductor portion is an N-type semiconductor, the ratio of the sum of the lengths of all first contacts in the same first collector structure to the length of the first transmission portion can be greater than the ratio of the sum of the lengths of all second contacts in the same second collector structure to the length of the second transmission portion. The beneficial effect in this case can be referred to the aforementioned beneficial effect where the length of at least one first contact is greater than the length of at least one second contact, and will not be repeated here.

[0149] For example, when the first doped semiconductor portion is a P-type semiconductor and the second doped semiconductor portion is an N-type semiconductor, along the second direction, the ratio of the length of the first contact portion to the width of the first strip region electrically connected to the first contact portion is less than or equal to the ratio of the length of the second contact portion to the width of the second strip region electrically connected to the second contact portion. With this configuration, the length of the first contact portion is longer, which helps to shorten the carrier transport distance along the second direction and reduce the transport resistance. However, the longer length of the first transport portion can lead to damage to the passivation layer, resulting in passivation loss. Considering that passivation loss has a greater impact on battery efficiency and that the first strip region has poor conductivity, the ratio of the length of the first contact portion to the width of the first strip region electrically connected to the first contact portion is set to be relatively small, while the ratio of the length of the second contact portion to the width of the second strip region electrically connected to the second contact portion is set to be relatively large. This can increase the number of carriers collected by the first contact portion, thereby achieving a better matching state between the carriers collected by the first and second contact portions, thus improving power generation efficiency.

[0150] For example, when the first doped semiconductor portion is a P-type semiconductor and the second doped semiconductor portion is an N-type semiconductor, the ratio between the length of the first contact portion and the distance between two adjacent first contacts along the second direction is greater than or equal to the ratio between the length of the second contact portion and the distance between two adjacent second contacts. With this configuration, the conductivity of the P-type first doped semiconductor portion is worse than that of the N-type second doped semiconductor portion. To collect more holes, it is necessary to increase the length of the first contact portion or decrease the distance between two adjacent first contacts. However, considering that the transmission resistance of carriers to the first contact portion along the second direction has been improved because the length of the first contact portion along the second direction is greater than its width along the first direction, further increasing the length of the first contact portion would cause the first contact portion to extend beyond the first strip region (e.g., by printing). Therefore, by decreasing the distance between two adjacent first contacts, the first contact portion is prevented from extending beyond the first strip region. In other words, by setting a larger ratio between the length of the first contact portion and the distance between two adjacent first contacts, it is possible to ensure that more carriers are collected from the P-type first doped semiconductor portion.

[0151] In addition, such as Figure 3As shown, the minimum distance between the end of the first contact portion 17 and the edge of the first strip region 13 electrically connected to the first contact portion 17 along the second direction can be defined as L1. The distance between two adjacent first contacts 17 in the first collector structure 15 along the first direction is defined as L2. The minimum distance between the end of the first transmission portion 16 (the end of the first transmission portion 16 can be an end near the edge of the semiconductor substrate, or an end present when there is a break in the first transmission portion 16) and the edge of the first strip region 13 electrically connected to the first transmission portion 16 along the first direction is defined as L3. The relationship between L1, L2, and L3 can be determined based on requirements such as carrier collection efficiency, overprinting tolerance of the first contact portion 17 and the first transmission portion 16, and manufacturing cost of the first collector structure 15 in practical applications.

[0152] For example, L1 and 0.5 The difference between L1 and L2 can be greater than or equal to -100 μm and less than or equal to 370 μm. For example: L1 and 0.5 The difference in L2 can be -100μm, -80μm, -60μm, -40μm, -20μm, -10μm, 0μm, 20μm, 50μm, 100μm, 150μm, 200μm, 240μm, 275μm, 300μm, 320μm, 350μm, or 370μm, etc. This configuration allows the distance traveled by charge carriers in the first stripe along the first direction to the nearest first contact to be closer to the distance traveled by charge carriers in the first stripe along the second direction to the nearest first contact, thus facilitating the collection of more charge carriers and reducing carrier recombination.

[0153] Where L1 can be greater than 0.5 L2; When the transport capability of the first doped semiconductor is high, L1 can be set to be greater than 0.5. L2 prevents the first contact from becoming too long due to an excessively small L1, which would result in high manufacturing costs for the first contact, and / or prevent the end of the first contact from being too close to the edge of the first strip area, which would result in excessively high precision requirements for printing the first contact on the first strip area. This also reduces the severe recombination caused by the end of the first contact extending beyond the edge of the first strip area and directly contacting the semiconductor substrate.

[0154] Alternatively, L1 can also be less than 0.5. L2. With this setting, if process deviations allow, L1 can be set to a smaller value, which can reduce passivation losses.

[0155] For example, L1 is greater than or equal to 50 μm and less than 300 μm. For instance, L1 can be 50 μm, 80 μm, 100 μm, 120 μm, 150 μm, 180 μm, 200 μm, 240 μm, 260 μm, or 299 μm. This setting prevents severe metal-semiconductor recombination caused by process errors during the manufacturing of the first contact portion due to an excessively small L1, which would result in the first contact portion forming in the area between two adjacent first strip regions, thus reducing losses. Secondly, it also prevents high carrier transport losses along the second direction due to an excessively large L1 causing the length of the first contact portion to be too small, thus reducing carrier recombination. Simultaneously, it also helps improve the overprinting tolerance of the first contact portion and the first transport portion, improving manufacturing yield. The minimum distance L1 between the end of the first contact portion 17 and the edge of the first strip region 13 electrically connected to the first contact portion 17 affects the allowable printing offset in the process. If L1 is too small, the end of the first contact portion will extend beyond the first strip region when the first contact portion 17 is formed by printing. The transport capability of charge carriers in the first strip region affects the transmission resistance of charge carriers to the first contact portion along the second direction. Therefore, setting L1 to be greater than or equal to 50μm and less than 300μm can take into account process deviation, transmission resistance and overprinting.

[0156] For example, L3 is greater than or equal to 50 μm and less than 150 μm. For instance, L3 can be 50 μm, 60 μm, 70 μm, 80 μm, 100 μm, 120 μm, 140 μm, or 149 μm. This setting prevents the length of the first transmission section from becoming too large due to an excessively small L3, which helps reduce the manufacturing cost of the first transmission section and decreases its light-shielding area. Furthermore, in the case of a back-contact solar cell, it also prevents the requirements for printing the first and second current collector structures and / or the risk of leakage from being too high due to the distance between the end of the first transmission section along the first direction and the second current collector structure with opposite polarity being too close; it also prevents the first contact section from forming outside the first strip region. Secondly, it also prevents the carriers in the two edge regions along the first direction from needing to travel a long distance to be collected and discharged by the first contact section and the first transmission section due to an excessively large L3, which helps reduce carrier recombination in the two edge regions along the first direction.

[0157] Furthermore, in cases where the solar cell includes multiple second terminal lines, and the first strip region is disconnected at its intersection with the second terminal lines, the distance from the edge of the first contact portion closest to the edge of the disconnection point of the first strip region to the edge of the first strip region is defined as L4. The size of L4 can be determined based on the printing requirements of the first contact portion and the requirements for carrier collection efficiency in the actual application scenario.

[0158] For example, L4 can be smaller than the distance L2 between two adjacent first contact portions. This setting can prevent excessive transmission loss of charge carriers at the edge of the first strip-shaped region break from reaching the nearest first contact portion due to an excessively large L4, thereby reducing charge carrier recombination.

[0159] Alternatively, L4 can be greater than or equal to the distance L2 between two adjacent first contacts. This configuration helps prevent the first contacts from being printed outside the first doped semiconductor portion, thus reducing recombination losses.

[0160] For example, when the first doped semiconductor portion is a P-type semiconductor and the second doped semiconductor portion is an N-type semiconductor, the width of the first transport portion can be greater than the width of the second transport portion. With this configuration, when the conductivity of the first doped semiconductor portion is lower than that of the second doped semiconductor portion, setting the width of the first transport portion to be greater than the width of the second transport portion reduces the transport resistance of the first transport portion, allowing the collection of the first and second transport portions to reach or nearly reach equilibrium, which is beneficial for improving power generation efficiency. Furthermore, when the width of the first strip region is greater than the width of the second strip region, from a process-acceptable perspective, the width of the first transport portion formed in the first strip region can be larger, which further reduces the transport resistance of the first transport portion.

[0161] Alternatively, if the first doped semiconductor section is a P-type semiconductor and the second doped semiconductor section is an N-type semiconductor, the width of the first transmission section can also be equal to the width of the second transmission section.

[0162] Furthermore, in practical applications, in at least one first collector structure, the centerline extending along the first direction of the first contact portion can coincide with or be staggered from the centerline extending along the first direction of the first transmission portion. The spacing between their centerlines extending along the first direction can be determined according to the overlay requirements of the first contact portion and the first transmission portion in the actual application scenario.

[0163] For example, in at least one first current collector structure, the distance between the centerline of the first contact portion extending along the first direction and the centerline of the first transmission portion extending along the first direction can be greater than or equal to 0 and less than or equal to half the length of the first contact portion. This arrangement prevents the effective contact area of ​​the first contact portion in the same first current collector structure from being too large, resulting in a smaller projection length along the second direction onto the first transmission portion. This helps reduce the transmission resistance of charge carriers from the first contact portion to the first transmission portion, thus reducing losses. Simultaneously, it avoids the problem of uneven charge carrier transmission in different regions of the first contact portion along the second direction, thereby improving the conversion efficiency of the solar cell.

[0164] In addition, such as Figure 3As shown, at least one portion of the first contact portion 17 along the second direction may not be in direct contact with the first transmission portion 16. Alternatively, as... Figure 10 As shown, at least one of the first contact portions 17 may have each region along the second direction in direct contact with the first transmission portion 16.

[0165] As for the portion that directly contacts the first contact portion and the first transmission portion, its proportion in the first contact portion (or its proportion in the width direction of the first transmission portion) can be determined according to the requirements of the contact area of ​​the first contact portion and the first transmission portion in the actual application scenario.

[0166] For example, such as Figure 4 As shown, in the same first collector structure 15, the length of the orthographic projection of at least one first contact portion 17 onto the first transmission portion 16 along the second direction can be greater than or equal to half the width of the first transmission portion 16. This arrangement is beneficial for having a larger effective contact area between the first transmission portion 16 and the first contact portion 17, reducing contact resistance, and facilitating the timely extraction of charge carriers.

[0167] The solar cell further includes a second doped semiconductor section and multiple second current collector structures. Furthermore, when the second current collector structure includes a second transmission section and multiple second contacts, the relationship between the length of the orthographic projection of the first contact on the first transmission section along the second direction and the length of the orthographic projection of the second contact on the second transmission section along the second direction can be set according to the conductivity type of the first and second doped semiconductor sections and actual requirements.

[0168] For example, when the first doped semiconductor portion is a P-type semiconductor and the second doped semiconductor portion is an N-type semiconductor, the ratio of the sum of the projected areas of all first contacts in the same first collector structure to the area of ​​the first transmission portion can be greater than the ratio of the sum of the projected areas of all second contacts in the same second collector structure to the area of ​​the second transmission portion. The application principle of this beneficial effect can be referenced from the previously described principle of the beneficial effect of the spacing between two adjacent first contacts being smaller than the spacing between two adjacent second contacts, and will not be repeated here.

[0169] Alternatively, the ratio of the sum of the projected areas of all first contacts on the semiconductor substrate in the same first collector structure to the area of ​​the first transmission section can also be equal to the ratio of the sum of the projected areas of all second contacts on the semiconductor substrate in the same second collector structure to the area of ​​the second transmission section.

[0170] As for the first transmission section included in the first collector structure, the size of the first transmission section can be determined according to the requirements of the transmission resistance and manufacturing cost of the first transmission section in the actual application scenario.

[0171] For example, along the second direction, the width of at least one first transmission portion is greater than or equal to 20 μm and less than or equal to 90 μm. For instance, the width of at least one first transmission portion can be 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 80 μm, or 90 μm, etc. This setting prevents excessively high transmission line resistance in the first transmission portion due to an excessively small width, thus reducing transmission loss. Furthermore, since the length of the first contact portion along the second direction is greater than its width along the first direction, printing is required along the second direction when forming the first contact portion using a printing process. Since the path height of the squeegee varies along the second direction, the width of the first transmission portion needs to be greater than or equal to 20 μm to ensure sufficient ink leakage, thereby ensuring a better linear shape of the first contact portion and allowing for more effective contact between the first contact portion and the first doped semiconductor portion. In addition, it can prevent excessive consumption of electrode material in manufacturing the first transmission section due to its excessive width, which helps control manufacturing costs; at the same time, it can reduce the shading effect of the first transmission section, which helps improve the light utilization rate of the solar cell.

[0172] Secondly, embodiments of the present invention provide a photovoltaic module, which includes: a plurality of solar cell strings and an encapsulation layer. The solar cell strings include a plurality of solar cells and a plurality of interconnecting structures for connecting the plurality of solar cells in series; or, the solar cell strings include a plurality of solar cells, with adjacent solar cells electrically connected together via a first transmission section. The solar cells are those provided in the first aspect and its various implementations. The encapsulation layer covers the surface of the solar cell strings.

[0173] The beneficial effects of the second aspect and its various implementations in the embodiments of the present invention can be referred to the analysis of the beneficial effects of the first aspect and its various implementations, and will not be repeated here.

[0174] The above description does not provide detailed explanations of the technical aspects of each layer's patterning, etching, etc. However, those skilled in the art should understand that various technical means can be used to form layers and regions of the desired shape. Furthermore, to form the same structure, those skilled in the art can also design methods that are not entirely identical to those described above. Additionally, although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination.

[0175] The embodiments of the present invention have been described above. However, these embodiments are merely for clarity and are not intended to limit the scope of the invention. The scope of the invention is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of the invention, and all such substitutions and modifications should fall within the scope of the invention.

Claims

1. A solar cell, characterized in that, include: A semiconductor substrate, comprising a first surface and a second surface opposite to each other; A first doped semiconductor portion is disposed in a portion region of or on a first surface of the semiconductor substrate; the first doped semiconductor portion includes a plurality of first strip-shaped regions extending along a first direction and spaced apart along a second direction; The first direction and the second direction intersect; A passivation layer is disposed on the side of the first doped semiconductor portion away from the semiconductor substrate; Multiple first collector structures are disposed on the passivation layer corresponding to the first doped semiconductor portion; each first collector structure includes a first transmission portion and multiple first contact portions electrically connected to the first transmission portion; in the same first collector structure, the first transmission portion extends along the first direction, the multiple first contact portions are spaced apart along the first direction, and the length of the first contact portion along the second direction is greater than the width of the first contact portion along the first direction; the multiple first contact portions pass through the passivation layer and are electrically connected to the first strip region, and the first transmission portion is disposed on the side of the first contact portion away from the semiconductor substrate; Wherein, along the second direction, the length of at least one of the first contact portions is greater than or equal to 30 μm and less than or equal to 75% of the width of the first strip region electrically connected to the first contact portion; and / or, in at least one of the first collector structures, the ratio of the width of the first transmission portion to the length of at least one of the first contact portions is greater than or equal to 10% and less than or equal to 200%.

2. The solar cell according to claim 1, characterized in that, In at least one of the first collector structures, the distance between two adjacent first contacts is greater than or equal to the length of the first contact.

3. The solar cell according to claim 2, characterized in that, In at least one of the first current collector structures, the ratio of the length of the first contact portion to the distance between two adjacent first contact portions is greater than or equal to 15% and less than or equal to 100%. And / or, in at least one of the first collector structures, the distance between two adjacent first contacts is greater than or equal to 50 μm and less than or equal to 300 μm; And / or, at least one of the first contact portions has a length greater than or equal to 50 μm and less than or equal to 150 μm.

4. The solar cell according to claim 1, characterized in that, Along the second direction, the length of at least one of the first contact portions is greater than or equal to 10% of the width of the first strip region electrically connected to the first contact portion; And / or, along the second direction, the width of at least one of the first transmission portions is greater than or equal to 20 μm and less than or equal to 90 μm.

5. The solar cell according to claim 1, characterized in that, Along the first direction, the width of at least one of the first contact portions is greater than or equal to 8 μm and less than or equal to 30 μm; And / or, the ratio between the length of at least one of the first contact portions and the width of the first contact portion is greater than or equal to 1.5 and less than or equal to 20.

6. The solar cell according to claim 1, characterized in that, Along the second direction, the minimum distance between the end of the first contact portion and the edge of the first strip-shaped area electrically connected to the first contact portion is defined as L1; along the first direction, the distance between two adjacent first contact portions in the first collector structure is defined as L2; ​​along the first direction, the minimum distance between the end of the first transmission portion and the edge of the first strip-shaped area electrically connected to the first transmission portion is defined as L3. Among them, L1 and 0.5 The difference in L2 is greater than or equal to -100μm and less than or equal to 370μm; And / or, L1 is greater than or equal to 50 μm and less than 300 μm; And / or, L3 is greater than or equal to 50 μm and less than 150 μm.

7. The solar cell according to claim 1, characterized in that, In at least one of the first collector structures, the distance between the centerline of the first contact portion extending in the first direction and the centerline of the first transmission portion extending in the first direction is greater than or equal to 0 and less than or equal to half the length of the first contact portion.

8. The solar cell according to claim 1, characterized in that, In the same first collector structure, the length of the orthographic projection of at least one of the first contact portions onto the first transmission portion along the second direction is greater than or equal to half the width of the first transmission portion.

9. The solar cell according to claim 1, characterized in that, In the same first collector structure, the lengths of the plurality of first contacts are the same; and / or, the two ends of the plurality of first contacts are respectively flush along the second direction. And / or, in the same first collector structure, the first transmission part is electrically connected to a column of first contacts; the center lines of multiple first contacts in the same column of first contacts that extend along the first direction coincide.

10. The solar cell according to claim 1, characterized in that, The solar cell further includes multiple sets of first electrical junctions, which are disposed on the passivation layer corresponding to the first doped semiconductor portion; the multiple sets of first electrical junctions are spaced apart along the first direction, each set of first electrical junctions includes multiple first electrical junctions spaced apart along the second direction, and each first electrical junction is electrically connected to the corresponding first current collector structure. The first electrical junction has an overlapping area with at least one of the first contact portions; And / or, along the second direction, the width of at least one of the first electrical junction portions is greater than or equal to the length of the first contact portion.

11. The solar cell according to claim 1, characterized in that, The solar cell further includes a second doped semiconductor section, multiple second current collector structures, and multiple sets of second electrical junctions; The second doped semiconductor portion is disposed in a portion of the first surface of the semiconductor substrate or on it, and the second doped semiconductor portion and the first doped semiconductor portion have opposite conductivity types; the second doped semiconductor portion includes a plurality of second strip regions extending along the first direction and spaced apart along the second direction; the second strip regions and the first strip regions are alternately distributed along the second direction; the passivation layer is also disposed on the side of the second doped semiconductor portion away from the semiconductor substrate; each second collector structure passes through the passivation layer and is electrically connected to the second strip region; Multiple sets of second electrical junctions are spaced apart along the first direction; each set of second electrical junctions includes multiple second electrical junctions spaced apart along the second direction, and each second electrical junction is electrically connected to a corresponding second current collector structure. In at least one of the first collector structures, the first transmission section is disconnected at the intersection with the extension line of each group of second electrical junctions, and in the first collector structure, the spacing between two adjacent first contact sections near the disconnection point of the first transmission section is different from the spacing between two adjacent first contact sections away from the disconnection point of the first transmission section.

12. The solar cell according to claim 11, characterized in that, In the same group of second electrical junctions, the area between two adjacent second electrical junctions is defined as the first region; the area between two adjacent groups of second electrical junctions is defined as the second region. The spacing between two first contact portions located in the first region and adjacent to each other along the first direction is different from the spacing between two first contact portions located in the second region and adjacent to each other along the first direction.

13. The solar cell according to claim 11, characterized in that, The solar cell further includes a plurality of second terminal wires; each second terminal wire is disposed on at least one side of each group of second electrical junctions along the second direction and is electrically connected to the outermost second electrical junction in the group of second electrical junctions; The first strip area is interrupted at the intersection with the second end line, and the distance from the first contact portion closest to the edge of the first strip area to the edge of the first strip area is L4. L4 is less than the distance between two adjacent first contact portions.

14. The solar cell according to claim 1, characterized in that, The solar cell further includes a second doped semiconductor section and a plurality of second current collector structures; The second doped semiconductor portion is disposed in a portion region of or on the first surface of the semiconductor substrate; the second doped semiconductor portion includes a plurality of second strip regions extending along the first direction and spaced apart along the second direction; the second strip regions and the first strip regions are alternately distributed along the second direction; The passivation layer is also disposed on the side of the second doped semiconductor portion away from the semiconductor substrate; Multiple second collector structures are disposed on the passivation layer corresponding to the second doped semiconductor portion; The second collector structure includes a second transmission section and a plurality of second contact sections electrically connected to the second transmission section; in the same second collector structure, the second transmission section extends along the first direction, and the plurality of second contact sections are spaced apart along the first direction, and the length of the second contact section along the second direction is greater than the width of the second contact section along the first direction. A plurality of second contacts pass through the passivation layer and are electrically connected to the second strip region, and the second transmission portion is disposed on the side of the second contacts away from the semiconductor substrate; The first doped semiconductor portion is a P-type semiconductor, the second doped semiconductor portion is an N-type semiconductor, and along the first direction, the distance between two adjacent first contact portions is less than the distance between two adjacent second contact portions, and / or, along the second direction, the length of at least one first contact portion is greater than or equal to the length of at least one second contact portion.

15. The solar cell according to claim 14, characterized in that, Along the second direction, the width of the first strip region is greater than the width of the second strip region; And / or, the semiconductor substrate is an N-type semiconductor; And / or, the width of the first transmission unit is greater than the width of the second transmission unit.

16. The solar cell according to claim 14, characterized in that, The ratio of the sum of the projected areas of all the first contacts on the semiconductor substrate in the same first collector structure to the area of ​​the first transmission portion is greater than the ratio of the sum of the projected areas of all the second contacts on the semiconductor substrate in the same second collector structure to the area of ​​the second transmission portion. And / or, the ratio of the sum of the lengths of all the first contacts in the same first collector structure to the length of the first transmission section is greater than the ratio of the sum of the lengths of all the second contacts in the same second collector structure to the length of the second transmission section.

17. The solar cell according to claim 14, characterized in that, Along the second direction, the ratio of the length of the first contact portion to the width of the first strip region electrically connected to the first contact portion is less than or equal to the ratio of the length of the second contact portion to the width of the second strip region electrically connected to the second contact portion.

18. The solar cell according to claim 14, characterized in that, Along the second direction, the ratio between the length of the first contact portion and the distance between two adjacent first contact portions is greater than or equal to the ratio between the length of the second contact portion and the distance between two adjacent second contact portions.

19. The solar cell according to claim 1, characterized in that, The material of at least one of the first contact portions includes at least one of silver, nickel, silver-plated nickel, and titanium; And / or, the material of the first transmission section includes at least one of copper, silver-plated copper, and aluminum; And / or, the thickness of the first transmission portion is greater than the thickness of the first contact portion; And / or, the first contact portion burns through the passivation layer and is electrically connected to the first strip region; or, at least one through contact window is provided on the passivation layer, and the first contact portion is electrically connected to the first strip region through the contact window.

20. A photovoltaic module, characterized in that, include: Multiple solar cell strings; wherein the solar cell string includes multiple solar cells and multiple interconnecting structures, the interconnecting structures being used to connect the multiple solar cells in series; or, the solar cell string includes multiple solar cells, with adjacent solar cells electrically connected together via a first transmission section; the solar cells are the solar cells according to any one of claims 1 to 19; And an encapsulation layer that covers the surface of the solar cell string.

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