CN-224205527-U - HJT solar cell, cell string, cell module and photovoltaic system

Abstract

The application is suitable for the technical field of solar cells, and provides HJT solar cells, a cell string, a cell assembly and a photovoltaic system, wherein in HJT solar cells, a plurality of first welding seed layers are directly arranged on a first transparent conductive film to be directly welded with welding strips, when the cell string and the cell assembly are formed, the first welding strips are only required to be directly covered on the first welding seed layers in parallel to be welded with the first welding seed layers, the series connection between the cells can be realized, electrodes are not required to be formed on the first transparent conductive film by adopting printing silver paste, and then the current is collected in a mode of welding the welding strips, so that the cost is greatly reduced. Meanwhile, the first transparent conductive film does not need to be subjected to copper electroplating to manufacture the battery, and the yield of products can be improved. In addition, by arranging the first oxidation-resistant protective layer on the first welding seed layer, the first welding seed layer can be effectively prevented from being exposed to air for a long time to generate oxides so as to cause poor welding performance.

Inventors

• XU ZHIGANG
• WANG YONGQIAN
• CHEN GANG

Assignees

• 珠海富山爱旭太阳能科技有限公司
• 天津爱旭太阳能科技有限公司
• 广东爱旭科技有限公司
• 浙江爱旭太阳能科技有限公司
• 深圳爱旭数字能源技术有限公司

Dates

Publication Date

20260505

Application Date

20240628

Claims (20)

1. 1. HJT solar cell, characterized in that it comprises: A silicon wafer having opposing first and second surfaces; sequentially stacking a first intrinsic amorphous silicon layer, a first doped amorphous silicon layer and a first transparent conductive film which are arranged on the first surface; Sequentially stacking a second intrinsic amorphous silicon layer, a second doped amorphous silicon layer and a second transparent conductive film which are arranged on the second surface; The first welding seed layers are arranged at intervals along a first direction, extend along a second direction and cross the first direction, and are used for welding with a welding strip which is positioned above the first welding seed layers and covers the first welding seed layers; A first oxidation-resistant protective layer disposed on the first solder seed layer, and And a current collecting structure disposed on the second transparent conductive film.
2. 2. The solar cell HJT of claim 1, wherein said first solder seed layer comprises a seed copper layer, and/or The first oxidation-resistant protective layer comprises at least one of a tin layer, a nickel layer and a metal oxide layer.
3. 3. The HJT solar cell according to claim 1, wherein the first oxidation protective layer includes at least one of a tin layer, a nickel layer, and a metal oxide layer.
4. 4. The HJT solar cell according to claim 1, wherein the first oxidation protection layer is a magnetic layer or has a magnetic material therein, so that the first oxidation protection layer can generate magnetic attraction to the solder strip.
5. 5. The solar cell HJT according to claim 1, wherein the first solder seed layer has a thickness of 60nm-150nm, and/or The thickness of the first oxidation resistant protective layer is 50nm-20um.
6. 6. The HJT solar cell according to claim 1, wherein the first solder seed layer has a magnetic material therein to enable the first solder seed layer to create a magnetic attraction to the solder ribbon.
7. 7. The HJT solar cell according to claim 1, wherein the current collection structure includes a plurality of second solder seed layers, the plurality of second solder seed layers also being arranged at intervals along the first direction, and the second solder seed layers each extending along the second direction; The second welding seed layer is used for being welded with a welding strip which is positioned above the second welding seed layer and covers the second welding seed layer.
8. 8. The HJT solar cell according to claim 7, wherein the thickness of the second solder seed layer is 60nm to 150nm.
9. 9. The HJT solar cell according to claim 7, wherein a second oxidation protection layer is disposed on the second solder seed layer.
10. 10. The HJT solar cell according to claim 9, wherein the second oxidation protective layer includes at least one of a tin layer, a nickel layer, and a metal oxide layer.
11. 11. The HJT solar cell according to claim 9, wherein the second oxidation protection layer is a magnetic layer or has a magnetic material therein, so that the second oxidation protection layer can generate magnetic attraction to the solder strip.
12. 12. The HJT solar cell according to claim 9, wherein the thickness of the second oxidation protection layer is 50nm to 20um.
13. 13. The HJT solar cell according to claim 7, wherein the second solder seed layer has a magnetic material therein to enable the second solder seed layer to create a magnetic attraction to the solder ribbon.
14. 14. A battery string, comprising: A plurality of HJT solar cells as defined in any one of claims 1-13, a plurality of HJT solar cells arranged in spaced relation along the second direction, all of the HJT solar cells being disposed in the same direction, and A first solder strip disposed on the first solder seed layer, the first solder strip covering and being soldered with the first solder seed layer; The first solder strip on the nth HJT solar cell is electrically connected with the current collecting structure of the (n+1) th HJT solar cell, and N is a positive integer.
15. 15. The battery string of claim 14, wherein the current collection structure comprises a plurality of second solder seed layers formed on the second transparent conductive film and spaced apart along the first direction; The first solder strip on the nth HJT solar cell sheet is bent and extended towards the side where the second solder seed layer of the (n+1) th HJT solar cell sheet is located at the interval area of two adjacent HJT solar cells and is soldered with the second solder seed layer.
16. 16. The battery string of claim 15, wherein the first solder strip comprises a first flat portion that overlies and is soldered to the first solder seed layer of an nth HJT solar cell, a bent portion that overlies and is soldered to the second solder seed layer of an n+1th HJT solar cell at a spaced apart region of adjacent two HJT solar cells, and a second flat portion that overlies and is soldered to the second solder seed layer.
17. 17. The battery string of claim 15, wherein the battery string includes at least one end cell positioned at an end of the battery string, the second weld seed layer on the end cell not being covered by the first weld strap, and the battery string further includes a second weld strap disposed on and welded to the second weld seed layer of the end cell.
18. 18. The battery string of claim 14, wherein the current collection structure comprises a plurality of second solder seed layers formed on the second transparent conductive film and spaced apart along the first direction; The battery string further comprises a third welding strip arranged on the second welding seed layer and welded with the second welding seed layer, and a conductive connecting piece arranged at the interval area of two adjacent HJT solar battery pieces, wherein the conductive connecting piece is connected with the first welding strip on the Nth HJT solar battery piece and the third welding strip on the (n+1) th HJT solar battery piece.
19. 19. A battery assembly comprising the battery string of any one of claims 14-18.
20. 20. A photovoltaic system comprising the cell assembly of claim 19.

Description

HJT solar cell, cell string, cell module and photovoltaic system Technical Field The application relates to the technical field of solar cells, in particular to HJT solar cells, a cell string, a cell assembly and a photovoltaic system. Background Currently, in HJT solar cells (heterojunction solar cells) in the photovoltaic industry, low-temperature silver paste is printed or copper is electroplated on a TCO film to form an electrode, and a copper electrode formed by silver grid lines or copper is used as a line conductor to achieve the purpose of current collection. However, the material for printing the low-temperature silver paste is very expensive, the cost is greatly increased, the copper electroplating process is not mature enough, the difficulty is high, and the yield of the product is low. Disclosure of utility model The application provides HJT solar cells, a cell string, a cell assembly and a photovoltaic system. The application is realized in such a way that HJT solar cells of the embodiments of the application include: A silicon wafer having opposing first and second surfaces; sequentially stacking a first intrinsic amorphous silicon layer, a first doped amorphous silicon layer and a first transparent conductive film which are arranged on the first surface; Sequentially stacking a second intrinsic amorphous silicon layer, a second doped amorphous silicon layer and a second transparent conductive film which are arranged on the second surface; The first welding seed layers are arranged at intervals along a first direction, extend along a second direction and cross the first direction, and are used for welding with a welding strip which is positioned above the first welding seed layers and covers the first welding seed layers; A first oxidation-resistant protective layer disposed on the first solder seed layer, and And a current collecting structure disposed on the second transparent conductive film. Further, the first solder seed layer comprises a seed copper layer, and/or The first oxidation-resistant protective layer comprises at least one of a tin layer, a nickel layer and a metal oxide layer. Still further, the first oxidation-resistant protective layer includes at least one of a tin layer, a nickel layer, and a metal oxide layer. Further, the first oxidation protection layer is a magnetic layer or a magnetic material is arranged in the first oxidation protection layer, so that the first oxidation protection layer can generate magnetic attraction force on the welding strip. Further, the first solder seed layer has a thickness of 60nm to 150nm, and/or The thickness of the first oxidation resistant protective layer is 50nm-20um. Still further, the first solder seed layer has a magnetic material therein such that the first solder seed layer is capable of generating a magnetic attraction force on the solder strip. Still further, the current collecting structure includes a plurality of second soldering seed layers, the plurality of second soldering seed layers are also arranged at intervals along the first direction, and the second soldering seed layers all extend along the second direction; The second welding seed layer is used for being welded with a welding strip which is positioned above the second welding seed layer and covers the second welding seed layer. Still further, the second solder seed layer has a thickness of 60nm to 150nm. Further, a second oxidation-resistant protective layer is arranged on the second welding seed layer. Still further, the second oxidation-resistant protective layer includes at least one of a tin layer, a nickel layer, and a metal oxide layer. Furthermore, the second oxidation protection layer is a magnetic layer or a magnetic material is arranged in the second oxidation protection layer, so that the second oxidation protection layer can generate magnetic attraction force on the welding strip. Further, the thickness of the second oxidation resistant protective layer is 50nm-20um. Still further, the second solder seed layer has a magnetic material therein to enable the second solder seed layer to generate a magnetic attraction force to the solder strip. The present application also provides a battery string including: A plurality of HJT solar cells of any one of the above, a plurality of HJT solar cells arranged at intervals along the second direction, all HJT solar cells being arranged in the same direction, and A first solder strip disposed on the first solder seed layer, the first solder strip covering and being soldered with the first solder seed layer; The first solder strip on the nth HJT solar cell is electrically connected with the current collecting structure of the (n+1) th HJT solar cell, and N is a positive integer. Still further, the current collecting structure includes a plurality of second solder seed layers formed on the second transparent conductive film and spaced apart along the first direction; The first solder strip on the nth HJT solar cell sh