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CN-121619999-B - Solar cell, cell module and photovoltaic system

CN121619999BCN 121619999 BCN121619999 BCN 121619999BCN-121619999-B

Abstract

The present disclosure provides a solar cell, a cell assembly, and a photovoltaic system. The solar cell comprises a substrate, a first electrode layer and a first insulating layer, wherein the first electrode layer and the first insulating layer are sequentially arranged on the first surface of the substrate along the direction away from the substrate. The first insulating layer is provided with a plurality of first openings, and the first openings are internally provided with conductive welding pieces. The first electrode layer is welded to an outer member through the conductive welding member. The present disclosure can omit a tin metal layer and prevent oxidation of an electrode layer.

Inventors

  • Feng Mengxian
  • Song Banghao
  • WU YINQI
  • LIU RUIMIN
  • WANG YONGQIAN

Assignees

  • 浙江爱旭太阳能科技有限公司
  • 天津爱旭太阳能科技有限公司
  • 山东爱旭太阳能科技有限公司
  • 珠海富山爱旭太阳能科技有限公司

Dates

Publication Date
20260512
Application Date
20260130

Claims (20)

  1. 1. The solar cell is characterized by comprising a substrate, a first surface doping layer, a first passivation layer, a first electrode layer and a first insulating layer, wherein the first surface doping layer, the first passivation layer, the first electrode layer and the first insulating layer are sequentially arranged on the first surface of the substrate along the direction away from the substrate; The first insulating layer is provided with a plurality of first openings, and the first openings are internally provided with conductive welding pieces; the first electrode layer is welded with an external part through the conductive welding part; The first electrode layer comprises a plurality of grid lines arranged on the first surface; The first insulating layer includes a plurality of first insulating strips; The plurality of first insulating strips are arranged in one-to-one correspondence with the plurality of grid lines, the plurality of first openings are distributed on at least one first insulating strip, and the arrangement positions of the first openings correspond to the positions of welding connection points on the grid lines; Wherein the plurality of gate lines on the first electrode layer pass through the first passivation layer to be in conductive contact with the first surface doped layer; the first surface doping layer comprises a first doping layer and a second doping layer, and the first doping layer and the second doping layer are alternately arranged on the first surface; the first electrode layer comprises a plurality of grid lines including first polarity fine grids and second polarity fine grids which extend along a first direction and are alternately arranged at intervals along a second direction, and first main grids and second main grids which extend along the second direction; Wherein the first direction intersects the second direction; the first polarity fine gate is in conductive contact with the first doped layer, and the second polarity fine gate is in conductive contact with the second doped layer; The first main grid is arranged on one side of the first polarity fine grid along the direction away from the substrate, is connected with the first polarity fine grid and is spaced from the second polarity fine grid; The second main grid is arranged at one side of the second polarity fine grid along the direction away from the substrate, is connected with the second polarity fine grid and is spaced from the first polarity fine grid; A third opening is formed in the first insulating strip on the first polar fine grid and the second polar fine grid, and the setting position of the third opening corresponds to the connection position of the first polar fine grid and the first main grid and the connection position of the second polar fine grid and the second main grid respectively; the plurality of first openings are distributed on the first insulating strips on the first main grid and the second main grid, the arrangement positions of the first openings correspond to the positions of the welding connection points on the first main grid and the second main grid, and the welding connection points are pad points.
  2. 2. The solar cell according to claim 1, wherein the first opening penetrates the first insulating strip in a width direction of the grid line.
  3. 3. The solar cell according to claim 1, wherein a length of the first opening in an extending direction of the grid line is in a range of 300 μm to 2200 μm.
  4. 4. The solar cell according to claim 1, wherein a height of the conductive solder is greater than a height of the first insulating strip in a thickness direction on the solar cell.
  5. 5. The solar cell according to claim 4, wherein the conductive solder comprises a first solder segment located within the first aperture and a second solder segment located higher than the first aperture, the second solder segment having a length in the direction of extension of the grid line that is greater than the length of the first aperture.
  6. 6. The solar cell of claim 4, wherein the first insulating strip has a height in the range of 8um to 80 um.
  7. 7. The solar cell according to claim 4, wherein a ratio of a height of the conductive solder to a height of the first insulating strip in a thickness direction on the solar cell is 1.6 to 10.
  8. 8. The solar cell of claim 6, wherein the ratio of the height of the first insulating strip to the length of the first opening is 0.5% to 12%.
  9. 9. The solar cell according to claim 5, wherein the length of the second soldering section is in the range of 550um to 2500um in the extending direction of the grid line.
  10. 10. The solar cell of claim 5, wherein the ratio of the height of the conductive solder to the length of the second solder segment is 2% to 55%.
  11. 11. The solar cell of claim 1, wherein a projected total area of the grid lines on the substrate is less than a sum of a projected total area of the first insulating strips on the substrate and a projected total area of the conductive solder on the substrate.
  12. 12. The solar cell according to claim 1, wherein a width of the first insulating stripe is larger than a width of each of the gate lines in the first electrode layer in a width direction of the gate lines.
  13. 13. The solar cell according to claim 1, wherein a width of the conductive solder is larger than a width of each of the grid lines in the first electrode layer in a width direction of the grid lines.
  14. 14. The solar cell according to claim 1, wherein a width of the conductive solder is larger than a width of the first insulating strip in a width direction of the grid line.
  15. 15. The solar cell of claim 1, wherein the conductive solder comprises a solder material metal, a solvent, and an activator.
  16. 16. The solar cell according to claim 15, wherein the solder material metal comprises one or more of tin, copper, silver, bismuth metals, and/or The solvent comprises one or more of carbitol, isopropanol, acetate solvent, and/or The activator comprises one or more of ethanolamine, triethanolamine and ethylenediamine.
  17. 17. The solar cell of claim 1, wherein the conductive solder has a hardness greater than 3H.
  18. 18. The solar cell of claim 1, wherein the first electrode layer comprises a copper metal layer.
  19. 19. The solar cell of claim 1, wherein the first insulating layer comprises an organic insulating material.
  20. 20. The solar cell according to claim 19, wherein the organic insulating material has a reflectivity of more than 40% for light in the wavelength range of 300nm to 1200 nm.

Description

Solar cell, cell module and photovoltaic system Technical Field The disclosure relates to the technical field of solar cells, in particular to a solar cell, a cell assembly and a photovoltaic system. Background In the manufacturing process of solar cells, electrodes made of conductive materials are generally prepared on the surface of a cell sheet and welded to an external solder ribbon by a welding material. In order to reduce the cost and improve the conductivity, the related art generally employs copper as an electrode material. However, copper electrodes are susceptible to oxidation with ambient oxygen to form insulating oxides, which lead to reduced electrode conductivity, increased contact resistance, and even to battery failure. In order to protect the copper electrode from moisture and oxygen in the environment, the related art generally covers a tin metal layer on the surface of the copper electrode. The tin metal layer has high chemical stability, can isolate air from directly contacting with a copper electrode, and realizes oxidation protection. In addition, the tin metal has good welding compatibility, can be used as an intermediate medium to realize reliable welding of the copper electrode and an external welding strip, and ensures effective output of current. However, the above tin metal layer has the following drawbacks. First, tin is relatively expensive and large area coverage of the electrodes increases material costs. Secondly, since tin has lower conductivity than copper, a tin metal layer continuously covering a copper electrode introduces additional resistance, affecting the current transmission efficiency of the electrode. Again, the related art generally uses solder as a soldering material, and both the solder and the tin metal layer are mainly composed of tin, which makes it difficult to control the soldering process between the tin metal layer and the solder. Disclosure of Invention There is a need in the art for a solution that can omit the tin metal layer and prevent oxidation of the electrode layer. To solve the above problems, the present disclosure provides a solar cell, a cell assembly, and a photovoltaic system. A first aspect including a substrate, and a first electrode layer and a first insulating layer covering the first electrode layer, which are sequentially provided on a first surface of the substrate in a direction away from the substrate; The first insulating layer is provided with a plurality of first openings, and the first openings are internally provided with conductive welding pieces; The first electrode layer is welded to an outer member through the conductive welding member. In some embodiments of the present invention, in some embodiments, The first electrode layer comprises a plurality of grid lines arranged on the first surface; The first insulating layer includes a plurality of first insulating strips; The first insulating strips are arranged in one-to-one correspondence with the grid lines, the first openings are distributed on at least one of the first insulating strips, and the arrangement positions of the first openings correspond to the positions of welding connection points on the grid lines. In some embodiments, further comprising: The first surface doping layer and the first passivation layer are positioned between the first electrode layer and the substrate and are sequentially arranged along the direction away from the substrate; Wherein the plurality of gate lines on the first electrode layer pass through the first passivation layer to be in conductive contact with the first surface doped layer. In some embodiments of the present invention, in some embodiments, The first surface doping layer comprises a first doping layer and a second doping layer, and the first doping layer and the second doping layer are alternately arranged on the first surface; The first electrode layer comprises a plurality of grid lines which comprise first polarity fine grids and second polarity fine grids, wherein the first polarity fine grids and the second polarity fine grids extend along a first direction and are alternately arranged at intervals along a second direction; Wherein the first direction intersects the second direction; the first polarity fine gate is in conductive contact with the first doped layer, and the second polarity fine gate is in conductive contact with the second doped layer; the first opening is arranged at a position corresponding to the welding connection point position on the first polarity fine grid and the second polarity fine grid. In some embodiments of the present invention, in some embodiments, The first surface doping layer comprises a first doping layer and a second doping layer, and the first doping layer and the second doping layer are alternately arranged on the first surface; the first electrode layer comprises a plurality of grid lines including first polarity fine grids and second polarity fine grids which extend along a first