Multi-main grid double-sided solar battery assembly

Abstract

The invention discloses a multi-main grid double-sided solar battery assembly, which comprises an assembly body which comprises a front film, a double-sided solar battery pack and a back film, wherein the double-sided solar battery pack is arranged between the front film and the back film; packaging adhesive films are arranged between the double-sided solar battery pack and the front film and between the double-sided solar battery pack and the back film; the double-sided solar battery pack comprises a plurality of multi-main grid double-sided solar battery pieces and metal wires; the metal wires extend between the adjacent battery pieces to achieve electric connection; a silicon substrate is arranged in the middle of each multi-main grid double-sided solar battery piece; 10-25 main grid lines and 70-500 secondary grid lines are arranged on the front surface and the reverse surface of each silicon substrate; the main grid lines are vertical to the secondary grid lines; welding spots are arranged on intersection points of the main grid lines and the secondary grid liens at intervals; and silver connection lines are arranged among the welding spots of the main grid lines. The contact resistance of the metal wires and the battery pieces can be reduced by optimizing the main grid line design of double-sided solar batteries; the offset problem in welding of a plurality of main grid lines is solved; the reliability and the power generation efficiency of the battery assembly are improved; and the production cost of the assembly is reduced.

Description

technical field [0001] The invention belongs to the technical field of photovoltaic modules, and in particular relates to a multi-busbar double-sided solar battery module. Background technique [0002] At present, the number of main grids of the mainstream crystalline silicon solar cell modules on the market is generally 3 grids, which are usually realized by automatic welding. From 3 to 4 or even 5, and in 2007, Day4 Energy technology proposed the idea of ​​busbar-free solar cells. This technology no longer prints busbars on solar cells, but uses multiple metal wires ( ≥10 pieces) instead of conventional soldering ribbons, while improving the cell efficiency (≥0.3%), it saves the amount of silver paste (≥30%) and reduces the cost of solar cells. The double-sided solar cells produced now , it can receive light and generate electricity on both sides. In addition to the power that can be output on the front side, the back side can also convert reflected, scattered or irradiat...

AI Technical Summary

Problems solved by technology

[0005] 1) The outer layer of the metal wire needs to be wrapped with a layer of low-temperature alloy. This technology is immature and will increase the cost of the metal wire;

[0006] 2) It needs to be fixed with an adhesive film, which will reduce the light transmittance of the module, increase the cost of the module, and affect the reliability of the module;

[0007] 3) The contact area between the metal wire and the auxiliary grid line is small, and the change of temperature difference is easy to cause desoldering;

[0008] 4) It is easy to produce offset during lamination

[0009] 2. "Passive film fixation method" puts the metal wire between the silicon wafer and the passivation film of the solar cell. Although it effectively solves the problems of welding offset and other problems, the coating technology in this technology is difficult, and it is currently difficult to batch Production

[0010] 3. The "U-shaped wire method" adopts a U-shaped wire structure (U-shaped wire method), which solves the problem that the wire is easy to bend to a certain extent, but there will also be deviations and weak welding. The silk process is also more complex

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