Solar cell structure

Abstract

The utility model discloses a solar cell structure, which comprises a silicon substrate, a first doping layer, a first passivation layer and a first metal electrode, and is characterized in that at least part of the first metal electrode penetrates through the first passivation layer to be in contact with the first doping layer; the first metal electrode comprises a first electrode unit and a second electrode unit, the first electrode unit comprises a first penetrating part penetrating through the first passivation layer and making contact with the first doping layer, and the projection area of the first penetrating part on the first doping layer accounts for 10%-30% of the projection area of the first electrode unit on the first doping layer; the second electrode unit comprises a second penetrating part which penetrates through the first passivation layer and is in contact with the first doping layer, and the projection area of the second penetrating part on the first doping layer accounts for 0%-3% of the projection area of the second electrode unit on the first doping layer, so that the metal recombination of the battery is reduced while good ohmic contact is ensured; the open-circuit voltage of the cell is effectively improved, and the conversion efficiency and the performance of the solar cell are improved.

Description

Technical Field

[0001] This application relates to the technical field of solar cells, and particularly to a solar cell structure. Background Art

[0002] For the front and back sub-grids of a passivated contact cell, the metal electrode requires a certain amount of glass content to burn through the passivation layer, so that the metal electrode forms a good ohmic contact with silicon or polysilicon. However, while the glass burns through the passivation layer to form a good ohmic contact, it will damage the passivation effect of the metal region, increasing the metal recombination of the cell. The prior art forms positive and negative electrodes by printing a first sub-grid on the front of the silicon substrate and a second sub-grid on the back. In order to reduce the metal recombination of the cell, the glass content in the paste of the second sub-grid is reduced, but this will lead to a poor contact resistance of the cell and cannot achieve both. Summary of the Utility Model

[0003] This application discloses a solar cell structure, which can reduce the metal recombination of the cell, effectively improve the open-circuit voltage of the cell, and improve the conversion efficiency and performance of the solar cell.

[0004] To achieve the above object, this application discloses a solar cell structure, including:

[0005] A silicon substrate, the silicon substrate including a first surface and a second surface;

[0006] A first doping layer, the first doping layer being disposed on the first surface;

[0007] A first passivation layer, the first passivation layer being disposed on a side of the first doping layer away from the silicon substrate;

[0008] A first metal electrode, the first metal electrode being disposed on a side of the first passivation layer away from the silicon substrate, at least a part of the first metal electrode passing through the first passivation layer to contact the first doping layer;

[0009] The first metal electrode includes a first electrode unit and a second electrode unit. The first electrode unit includes a first through portion passing through the first passivation layer to contact the first doping layer. The projected area of the first through portion on the first doping layer accounts for 10%-30% of the projected area of the first electrode unit on the first doping layer. The second electrode unit includes a second through portion passing through the first passivation layer to contact the first doping layer. The projected area of the second through portion on the first doping layer accounts for 0%-3% of the projected area of the second electrode unit on the first doping layer.

[0010] In a possible implementation, the first metal electrode includes a plurality of first sub-gate lines, the plurality of first sub-gate lines are arranged in parallel, each first sub-gate line includes a plurality of the first electrode units and a plurality of the second electrode units, the plurality of first electrode units extend along a first direction and are all located on a first straight line, the plurality of first electrode units are arranged at intervals, and two adjacent first electrode units are connected by the second electrode unit.

[0011] In a possible implementation, the first sub-gate line includes a first gate line and a second gate line arranged adjacent to each other, the first electrode units on the first gate line and the second electrode units on the second gate line are arranged corresponding to each other along a second direction, and the second direction is perpendicular to the first direction.

[0012] In a possible implementation, the first electrode unit and the second electrode unit are connected by a first jumper wire.

[0013] In a possible implementation, the width of the first jumper wire is greater than the width of the first electrode unit, and the width of the first jumper wire is greater than the width of the second electrode unit.

[0014] In a possible implementation, the length ratio of the first electrode unit to the second electrode unit is 0.25 - 4.

[0015] In a possible implementation, the first through portion includes first conductive grains, the second through portion includes second conductive grains, and the number of the first conductive grains is greater than the number of the second conductive grains.

[0016] In a possible implementation, the solar cell structure further includes:

[0017] A second doping layer, the second doping layer is disposed on the second surface;

[0018] A second passivation layer, the second passivation layer is disposed on a side of the second doping layer away from the silicon substrate;

[0019] A second metal electrode, the second metal electrode is disposed on a side of the second passivation layer away from the silicon substrate, and at least a part of the second metal electrode passes through the second passivation layer to contact the second doping layer;

[0020] The second metal electrode includes a third electrode unit and a fourth electrode unit. The third electrode unit includes a third through portion that passes through the second passivation layer and contacts the second doping layer. The projected area of the third through portion on the second doping layer accounts for 10%-30% of the projected area of the third electrode unit on the second doping layer. The fourth electrode unit includes a fourth through portion that passes through the second passivation layer and contacts the second doping layer. The projected area of the fourth through portion on the second doping layer accounts for 0%-3% of the projected area of the fourth electrode unit on the second doping layer.

[0021] In a possible implementation manner, the second metal electrode includes a plurality of second sub-gate lines. The plurality of second sub-gate lines are arranged in parallel. Each second sub-gate line includes a plurality of the third electrode units and a plurality of the fourth electrode units. The plurality of third electrode units extend along a third direction and are all located on a second straight line. The plurality of third electrode units are arranged at intervals, and two adjacent third electrode units are connected by the fourth electrode unit.

[0022] In a possible implementation manner, the second sub-gate line includes a third gate line and a fourth gate line arranged adjacent to each other. The third electrode units on the third gate line and the fourth electrode units on the fourth gate line are arranged corresponding to each other along a fourth direction. The fourth direction is perpendicular to the third direction.

[0023] Compared with the prior art, the beneficial effects of the present application are as follows:

[0024] In the present application, the silicon substrate provides a basic support for the battery, ensuring the overall stability and reliability of the battery. The first doping layer is provided on the first surface of the silicon substrate to improve the photoelectric conversion efficiency of the battery. The first passivation layer is provided on the side of the first doping layer away from the silicon substrate, which can reduce the recombination loss on the first surface and improve the performance of the battery. At least part of the first metal electrode passes through the first passivation layer to form a good ohmic contact with the first doping layer, which is beneficial to optimizing current collection and improving the output efficiency of the battery. The first metal electrode of the present application includes a first electrode unit and a second electrode unit. By setting the projected area of the first through portion of the first electrode unit on the first doping layer to account for 10%-30% of the projected area of the first electrode unit on the first doping layer, good electrical contact and current transmission can be ensured. The projected area of the second through portion of the second electrode unit on the first doping layer accounts for 0%-3% of the projected area of the second electrode unit on the first doping layer, thereby reducing metal recombination. While ensuring good ohmic contact, the metal recombination of the battery is reduced, effectively improving the open-circuit voltage of the battery, the conversion efficiency of the solar cell, and the performance of the battery. Description of the Drawings

[0025] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the accompanying drawings required in the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can be obtained based on these drawings.

[0026] Figure 1 It is a schematic diagram of the overall structure of a solar cell structure provided by an embodiment of the present utility model;

[0027] Figure 2 It is a schematic diagram of a solar cell structure provided by an embodiment of the present utility model, showing the first through part and the second through part;

[0028] Figure 3 It is a schematic diagram of a solar cell structure provided by an embodiment of the present utility model, showing the first sub-grid line;

[0029] Figure 4 It is a schematic diagram of a solar cell structure provided by an embodiment of the present utility model, showing the first jumper wire.

[0030] Explanation of reference numerals:

[0031] 10 - silicon substrate; 20 - first doping layer; 30 - first passivation layer; 40 - first metal electrode; 411 - first electrode unit; 4111 - first through part; 412 - second electrode unit; 4121 - second through part; 413 - first jumper wire; 50 - second doping layer; 60 - second passivation layer; 70 - second metal electrode; 80 - tunneling oxide layer. Detailed implementation manners

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, rather than all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0033] In the present application, the terms "install", "set", "be provided with", "connect", "be connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or there is internal communication between two devices, elements or components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific situations.

[0034] In addition, terms such as "first", "second", etc. are mainly used to distinguish different devices, components or parts (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, components or parts. Unless otherwise specified, the meaning of "a plurality" is two or more.

[0035] For the front and back sub-grids of the passivated contact cell, the metal electrode requires a certain amount of glass content to burn through the passivation layer, so as to form a good ohmic contact between the metal electrode and silicon or polysilicon. However, while the glass burns through the passivation layer to form a good ohmic contact, it will damage the passivation effect of the metal region, increasing the metal recombination of the cell. The prior art forms positive and negative electrodes by printing a first sub-grid on the front of the silicon substrate and a second sub-grid on the back. In order to reduce the metal recombination of the cell, the glass content in the paste of the second sub-grid is reduced, but this will lead to poor contact resistance of the cell and cannot achieve both.

[0036] In view of this, some embodiments of the present application provide a solar cell structure, which can reduce the metal recombination of the cell, effectively improve the open-circuit voltage of the cell, and improve the conversion efficiency and performance of the solar cell.

[0037] The present application will be described in detail through specific embodiments as follows:

[0038] The solar cell structure of the embodiment of the present application, as Figures 1-4 shown, the solar cell structure includes: a silicon substrate 10, the silicon substrate 10 includes a first surface and a second surface, and the silicon substrate 10 is used to provide basic support for the cell; a first doping layer 20, a first passivation layer 30 and a first metal electrode 40 are provided on the first surface of the silicon substrate 10, and at least part of the first metal electrode 40 passes through the first passivation layer 30 and contacts the first doping layer 20; a second doping layer 50, a second passivation layer 60 and a second metal electrode 70 are sequentially provided on the second surface of the silicon substrate 10, and at least part of the second metal electrode 70 passes through the second passivation layer 60 and contacts the second doping layer 50;

[0039] In the present application, the first metal electrode 40 includes a first electrode unit 411 and a second electrode unit 412. The first electrode unit 411 includes a first passing part 4111 that passes through the first passivation layer 30 and contacts the first doping layer 20. The projected area of the first passing part 4111 on the first doping layer 20 accounts for 10%-30% of the projected area of the first electrode unit 411 on the first doping layer 20. The second electrode unit 412 includes a second passing part 4121 that passes through the first passivation layer 30 and contacts the first doping layer 20. The projected area of the second passing part 4121 on the first doping layer 20 accounts for 0%-3% of the projected area of the second electrode unit 412 on the first doping layer 20.

[0040] It should be noted that the first surface can be the side facing away from the light, or the first surface can also be the side receiving the light.

[0041] In the solar cell structure provided by the embodiment of the present application, the silicon substrate 10 provides basic support for the battery, ensuring the overall stability and reliability of the battery. The first doping layer 20 is disposed on the first surface of the silicon substrate 10 to improve the photoelectric conversion efficiency of the battery. The first passivation layer 30 is disposed on the side of the first doping layer 20 away from the silicon substrate 10, which can reduce the recombination loss of the first surface and improve the performance of the battery. At least a part of the first metal electrode 40 passes through the first passivation layer 30 to form a good ohmic contact with the first doping layer 20, which is beneficial to optimizing current collection and improving the output efficiency of the battery. The first metal electrode 40 of the present application includes a first electrode unit 411 and a second electrode unit 412. The projected area of the first through portion 4111 of the first electrode unit 411 on the first doping layer 20 accounts for 10%-30% of the projected area of the first electrode unit 411 on the first doping layer 20, which can ensure good electrical contact and current transmission. The projected area of the second through portion 4121 of the second electrode unit 412 on the first doping layer 20 accounts for 0%-3% of the projected area of the second electrode unit 412 on the first doping layer 20, thereby reducing metal recombination. While ensuring good ohmic contact, the metal recombination of the battery is reduced, effectively improving the open-circuit voltage of the battery and enhancing the conversion efficiency and performance of the solar cell.

[0042] It should be noted that the ohmic contact in the battery refers to a special electrical contact formed between a metal and a semiconductor in the battery structure. This contact has a very low resistance, enabling current to flow freely between the metal electrode and the semiconductor without significant energy loss or voltage drop due to the existence of resistance. For example, in the battery of this application, good ohmic contacts need to be formed between the second metal electrode 70 and the second doping layer 50, and between the first metal electrode 40 and the first doping layer 20. When the projected area of the penetrating part of the grid line unit on the semiconductor layer accounts for 10%-30% of the projected area of the grid line unit on the semiconductor layer, good ohmic contact can be ensured. The metal recombination in the battery refers to the process in which electrons and holes (two types of carriers in the semiconductor) recombine and release energy between the metal and the semiconductor material in the battery structure. In the battery of this application, when the metal electrode contacts the semiconductor layer, due to the interface characteristics and the physical and chemical properties of the materials, some electrons and holes may recombine at this interface instead of flowing along the expected path to form current. Ideally, it is hoped that the electrons and holes generated by the battery can be collected by the metal electrode as much as possible instead of recombining inside the battery, because metal recombination will lead to current loss and reduce the efficiency of the battery. In this application, the projected area of the first penetrating part 4111 of the first electrode unit 411 on the first doping layer 20 accounts for 10%-30% of the projected area of the first electrode unit 411 on the first doping layer 20. The first electrode unit 411 enables a good ohmic contact to be formed between the first metal electrode 40 and the first doping layer 20. The projected area of the second penetrating part 4121 of the second electrode unit 412 on the first doping layer 20 accounts for 0%-3% of the projected area of the second electrode unit 412 on the first doping layer 20. The second electrode unit 412 can reduce the metal recombination between the first metal electrode 40 and the first doping layer 20. The same applies to the second metal electrode 70, thereby ultimately improving the battery efficiency, enhancing the battery stability, and increasing the open-circuit voltage and short-circuit current of the battery.

[0043] Specifically, for example Figure 3As shown, the first metal electrode 40 includes a plurality of first sub-grid lines which are arranged in parallel. Each first sub-grid line includes a plurality of first electrode units 411 and a plurality of second electrode units 412. In this way, each first sub-grid line has a different design of the passing part ratio, so that each first sub-grid line forms a good ohmic contact through the first passing part 4111 of the first electrode unit 411, and the second passing part 4121 of the second electrode unit 412 reduces metal recombination. The plurality of first electrode units 411 extend along the first direction and are all located on the first straight line. The plurality of first electrode units 411 are arranged at intervals, and adjacent two first electrode units 411 are connected by the second electrode unit 412. The first direction is the X direction in the figure. In this way, current can be effectively collected. Connecting adjacent first electrode units 411 through the second electrode unit 412 helps the uniform transmission of current in the first sub-grid line, avoiding efficiency loss caused by local current concentration. The specific arrangement and connection method of the first electrode unit 411 help to reduce the resistance of the first sub-grid line, improve the current transmission efficiency, and the uniformly distributed unit structure can reduce the non-uniformity of resistance, thereby improving the electrical performance of the first surface of the entire battery. This regular and orderly structure design can improve the mechanical stability of the first sub-grid line, reduce structural damage caused by factors such as stress or temperature change during use, and contribute to improving the long-term reliability and stability of the battery.

[0044] In addition, as Figure 3 shown, the first sub-grid line includes a first grid line and a second grid line which are arranged adjacent to each other. The first electrode units 411 on the first grid line and the second electrode units 412 on the second grid line are arranged corresponding to each other along the second direction. The second direction is perpendicular to the first direction, and the second direction is the Y direction in the figure. The first electrode units 411 on the first grid line and the second electrode units 412 on the second grid line are arranged corresponding to each other in the second direction, which helps the current to be more evenly distributed between different first sub-grid lines, avoiding local current concentration, and thus improving the overall current collection efficiency of the battery. This cross-corresponding layout can increase the integrity and stability of the first sub-grid line structure. When affected by external forces, temperature changes, etc., it can better resist deformation and damage, improving the reliability of the battery. This misaligned corresponding arrangement helps to improve the electric field distribution on the first surface of the battery, reduce electric field concentration and non-uniformity, reduce the probability of electron-hole recombination, increase the open-circuit voltage and short-circuit current of the battery, and achieve a more dense and orderly layout of the first metal electrode 40 in a limited area, improving the current transmission ability.

[0045] In this embodiment, as Figure 4As shown, the first electrode unit 411 and the second electrode unit 412 are connected by a first jumper wire 413. The first jumper wire 413 is used to prevent connection offset between the first electrode unit 411 and the second electrode unit 412, improving the reliability of the connection between the first electrode unit 411 and the second electrode unit 412, enhancing the stability of the first sub-gate line, enabling it to better withstand the influence of factors such as external stress and temperature changes, reducing the risk of structural deformation and damage. In addition, the first jumper wire 413 provides an additional current conduction path, helping the current to flow more smoothly between the first electrode unit 411 and the second electrode unit 412, reducing the resistance during current transmission, thereby improving the overall current collection efficiency. At the same time, it can reduce the contact resistance between the first electrode unit 411 and the second electrode unit 412, reducing the energy loss caused by resistance, enhancing the output performance of the battery, helping to distribute charges more evenly, avoiding excessive accumulation or lack of charges in some areas, and thus improving the electrical performance of the battery.

[0046] Furthermore, the width of the first jumper wire 413 is greater than the width of the first electrode unit 411, and the width of the first jumper wire 413 is greater than the width of the second electrode unit 412. The wider first jumper wire 413 can further enhance the reliability of the connection between the first electrode unit 411 and the second electrode unit 412. At the same time, it can provide a lower resistance channel, reducing the resistance loss during current transmission, helping to improve the current transmission efficiency. The wider first jumper wire 413 can withstand a larger current, avoiding local overheating or damage caused by excessive current, improving the reliability and stability of the battery, helping the current to be more evenly distributed between the electrode units, reducing the current concentration phenomenon, and thus optimizing the overall performance of the battery. It should be noted that the width of the first electrode unit 411 refers to the distance perpendicular to the first direction in the projection of the first electrode unit 411 on the first doping layer 20. The width of the first jumper wire 413 and the width of the second electrode unit 412 are the same in principle.

[0047] Further, the length ratio of the first electrode unit 411 to the second electrode unit 412 is 0.25 - 4. The length of the first electrode unit 411 refers to the distance along the first direction in the projection of the first electrode unit 411 on the first doping layer 20. The length of the second electrode unit 412 is defined similarly to that of the first electrode unit 411. A length ratio of the first electrode unit 411 to the second electrode unit 412 within the range of 0.25 - 4 can enable a good ohmic contact to be formed between the first metal electrode 40 and the first doping layer 20. When the length ratio of the first electrode unit 411 to the second electrode unit 412 is lower than 0.25, the contact between the metal electrode and silicon is poor, and the fill factor is low. A length ratio of the first electrode unit 411 to the second electrode unit 412 within the range of 0.25 - 4 can reduce the metal recombination between the first metal electrode 40 and the first doping layer 20. When the length ratio of the first electrode unit 411 to the second electrode unit 412 is higher than 4, the metal recombination is large, and the open-circuit voltage does not increase significantly.

[0048] In this embodiment, the metal electrode requires a certain glass content to burn through the passivation layer, enabling the conductive grains of the metal electrode to pass through the passivation layer and contact the doping layer. Therefore, the first passing part includes first conductive grains, and the second passing part includes second conductive grains. The number of the first conductive grains is greater than that of the second conductive grains. In this way, through the contact between the relatively large number of first conductive grains and the first doping layer 20, a good ohmic contact can be formed between the first metal electrode 40 and the first doping layer 20, while the number of the second conductive grains is small to reduce the metal recombination between the first metal electrode 40 and the first doping layer 20.

[0049] The solar cell structure further includes a second doping layer 50, a second passivation layer 60, and a second metal electrode 70. The second doping layer 50 is disposed on the second surface. The second passivation layer 60 is disposed on the side of the second doping layer 50 away from the silicon substrate 10. The second metal electrode 70 is disposed on the side of the second passivation layer 60 away from the silicon substrate 10. At least a part of the second metal electrode 70 passes through the second passivation layer 60 and contacts the second doping layer 50. Specifically, the second metal electrode 70 includes a third electrode unit and a fourth electrode unit. The third electrode unit includes a third passing part that passes through the second passivation layer 60 and contacts the second doping layer 50. The projected area of the third passing part on the second doping layer 50 accounts for 10% - 30% of the projected area of the third electrode unit on the second doping layer 50. The second electrode unit 412 includes a fourth passing part that passes through the second passivation layer 60 and contacts the second doping layer 50. The projected area of the fourth passing part on the second doping layer 50 accounts for 0% - 3% of the projected area of the fourth electrode unit on the second doping layer 50.

[0050] The projected area of the second through portion 4121 of the second electrode unit 412 on the first doping layer 20 accounts for 0%-3% of the projected area of the second electrode unit 412 on the first doping layer 20, thereby reducing metal recombination; the structural design of the second doping layer 50, the second passivation layer 60, and the second metal electrode 70 on the second surface of the silicon substrate 10 also helps to improve the photoelectric conversion efficiency and current collection efficiency of the second surface. The second metal electrode 70 includes a third electrode unit and a fourth electrode unit. By ensuring that the projected area of the third through portion of the third electrode unit on the second doping layer 50 accounts for 10%-30% of the projected area of the third electrode unit on the second doping layer 50, good electrical contact and current transmission can be guaranteed. The projected area of the fourth through portion of the fourth electrode unit on the second doping layer 50 accounts for 0%-3% of the projected area of the fourth electrode unit on the second doping layer 50, thereby reducing metal recombination.

[0051] Exemplarily, the first surface is the side facing away from the light, and the second surface is the side receiving the light. A tunneling oxide layer 80, a first doping layer 20, a first passivation layer 30, and a first metal electrode 40 are sequentially arranged on the first surface, and a second doping layer 50, a second passivation layer 60, and a second metal electrode 70 are sequentially arranged on the second surface. The first doping layer 20 can be a polysilicon layer, and the second doping layer 50 can be an emitter.

[0052] Similarly, the second metal electrode 70 includes a plurality of second sub-grid lines arranged in parallel. Each second sub-grid line includes a plurality of third electrode units and a plurality of fourth electrode units. The plurality of third electrode units extend along the third direction and are all located on the second straight line. The plurality of third electrode units are arranged at intervals, and adjacent two third electrode units are connected by the fourth electrode unit. In this way, each second sub-grid line has a different design of the through portion ratio, so that each second sub-grid line forms a good ohmic contact through the third through portion of the third electrode unit, and the fourth through portion of the fourth electrode unit reduces metal recombination, improving the reliability and stability of the battery.

[0053] Specifically, the second sub-grid line includes an adjacent third grid line and a fourth grid line. The third electrode units on the third grid line and the fourth electrode units on the fourth grid line are arranged corresponding to each other along the fourth direction. The fourth direction is perpendicular to the third direction, which helps the current to be more evenly distributed between different second sub-grid lines, avoiding local current concentration, and thus improving the overall current collection efficiency of the battery. This cross-corresponding layout can also increase the integrity and stability of the second sub-grid line structure.

[0054] In addition, the third electrode unit and the fourth electrode unit are connected by a second jumper wire, preventing the connection between the third electrode unit and the fourth electrode unit from shifting, improving the reliability of the connection between the third electrode unit and the fourth electrode unit, and enhancing the stability of the second sub-grid line.

[0055] Furthermore, the width of the second jumper line is greater than the width of the third electrode unit and greater than the width of the fourth electrode unit, which can further enhance the connection reliability between the third electrode unit and the fourth electrode unit, improving the reliability and stability of the battery.

[0056] Furthermore, the length ratio of the third electrode unit to the fourth electrode unit is 0.25 - 4. The third through portion includes third conductive grains, and the fourth through portion includes fourth conductive grains, and the number of the third conductive grains is greater than the number of the fourth conductive grains.

[0057] In this embodiment, the solar cell structure further includes a selective emitter, which is disposed corresponding to the third electrode unit. The selective emitter has different doping concentration regions, which can better match the current collection characteristics of the third electrode unit, thereby more effectively collecting carriers, increasing the current output, reducing the electron - hole recombination in the second doping layer 50 region, increasing the open - circuit voltage and short - circuit current of the battery, and further improving the overall efficiency of the battery, making the electrical performance of the battery more uniform and stable, and improving the reliability and stability of the battery.

[0058] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A solar cell structure, characterized in that, Comprising: A silicon substrate, the silicon substrate comprising a first surface and a second surface; A first doped layer, the first doped layer being disposed on the first surface; A first passivation layer, the first passivation layer being disposed on a side of the first doped layer away from the silicon substrate; A first metal electrode, the first metal electrode being disposed on a side of the first passivation layer away from the silicon substrate, at least a part of the first metal electrode passing through the first passivation layer to contact the first doped layer; The first metal electrode includes a first electrode unit and a second electrode unit, the first electrode unit includes a first passing portion passing through the first passivation layer to contact the first doped layer, and a projected area of the first passing portion on the first doped layer accounts for 10%-30% of a projected area of the first electrode unit on the first doped layer, the second electrode unit includes a second passing portion passing through the first passivation layer to contact the first doped layer, and a projected area of the second passing portion on the first doped layer accounts for 0%-3% of a projected area of the second electrode unit on the first doped layer.

2. The solar cell structure according to claim 1, wherein The first metal electrode includes a plurality of first sub-gate lines, the plurality of first sub-gate lines are arranged in parallel, each first sub-gate line includes a plurality of the first electrode units and a plurality of the second electrode units, the plurality of first electrode units extend along a first direction and are all located on a first straight line, the plurality of first electrode units are arranged at intervals, and two adjacent first electrode units are connected by the second electrode unit.

3. The solar cell structure according to claim 2, characterized in that, The first sub-gate line includes a first gate line and a second gate line arranged adjacent to each other, and the first electrode units on the first gate line and the second electrode units on the second gate line are arranged corresponding to each other along a second direction, the second direction being perpendicular to the first direction.

4. The solar cell structure according to claim 2, characterized in that The first electrode unit and the second electrode unit are connected by a first jumper wire.

5. The solar cell structure according to claim 4, wherein, A width of the first jumper wire is greater than a width of the first electrode unit, and the width of the first jumper wire is greater than a width of the second electrode unit.

6. The solar cell structure according to claim 2, characterized in that, A length ratio of the first electrode unit to the second electrode unit is 0.25-4.

7. The solar cell structure according to claim 1, wherein The first passing portion includes first conductive grains, the second passing portion includes second conductive grains, and a number of the first conductive grains is greater than a number of the second conductive grains.

8. The solar cell structure according to claim 1, characterized in that, The solar cell structure further includes: A second doped layer, the second doped layer being disposed on the second surface; A second passivation layer, the second passivation layer being disposed on a side of the second doped layer away from the silicon substrate; A second metal electrode, the second metal electrode being disposed on a side of the second passivation layer away from the silicon substrate, at least a part of the second metal electrode passing through the second passivation layer to contact the second doped layer; The second metal electrode includes a third electrode unit and a fourth electrode unit. The third electrode unit includes a third through portion that passes through the second passivation layer and contacts the second doped layer. The projected area of the third through portion on the second doped layer accounts for 10%-30% of the projected area of the third electrode unit on the second doped layer. The fourth electrode unit includes a fourth through portion that passes through the second passivation layer and contacts the second doped layer. The projected area of the fourth through portion on the second doped layer accounts for 0%-3% of the projected area of the fourth electrode unit on the second doped layer.

9. The solar cell structure according to claim 8, wherein, The second metal electrode includes a plurality of second sub-gate lines. The plurality of second sub-gate lines are arranged in parallel. Each second sub-gate line includes a plurality of the third electrode units and a plurality of the fourth electrode units. The plurality of third electrode units extend along a third direction and are all located on a second straight line. The plurality of third electrode units are arranged at intervals, and adjacent two of the third electrode units are connected by the fourth electrode unit.

10. The solar cell structure according to claim 9, characterized in that, The second sub-gate line includes a third gate line and a fourth gate line that are arranged adjacent to each other. The third electrode units on the third gate line and the fourth electrode units on the fourth gate line are arranged corresponding to each other along a fourth direction. The fourth direction is perpendicular to the third direction.

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