Fabrication method for welding module of flexible plastic substrate thin film GaAs solar cell

Abstract

The invention provides a fabrication method for a welding module of a flexible plastic substrate thin film GaAs solar cell. The fabrication method comprises the following steps of S1, pasting, in which anisotropic conductive glue is aligned and pasted onto each electrode of the solar cell after cutting; S2, pre-pressing, in which the anisotropic conductive glue in the step S1 is pre-pressed, and arelease-type protection film covering the conductive glue is removed; and S3, hot-pressing, in which an interconnection piece is aligned and pasted onto the conductive glue in the step S2 and then ishot-pressed. Thin film GaAs cell is welded by the fabrication method, and an insulation and protection process of a side wall of the cell can be omitted; if a connection position is broken or a problem occurs in conductivity due to unfavorable operation or excessively pulling, repeated hot-pressing and connection can be performed after a hot-pressing connection part is wiped clearly by a conductive glue removal liquid, and relatively large operation redundancy is achieved; and the connection firmness of the battery module fabricated by the process and the cell efficiency loss both reach or even exceed those of a conventional rigid GaAs welding level.

Description

technical field [0001] The invention relates to the field of thin-film gallium arsenide solar cells, in particular to a method for manufacturing a welded module of a flexible plastic substrate thin-film gallium arsenide solar cell. Background technique [0002] In the actual application of solar cells, it is necessary to weld the electrodes of a single cell to achieve effective connection between cells. Traditional rigid gallium arsenide solar cells use resistance welding process for interconnection sheet welding, the welding temperature is as high as 800-900 ℃, and the battery electrodes and interconnection sheet surface can be locally melted and welded together directly, and the welding firmness is greater than 0.83N / mm 2 , The relative value of battery efficiency welding loss is kept within 2%. In order to pursue ultra-high power-to-weight ratio in flexible thin-film GaAs solar cells, flexible polyimide plastic film is generally used as the supporting substrate of the ba...

AI Technical Summary

Problems solved by technology

In order to pursue ultra-high power-to-weight ratio in flexible thin-film GaAs solar cells, flexible polyimide plastic film is generally used as the supporting substrate of the battery. 200~300℃, the conventional resistance welding process will cause severe ablation of the battery substrate, so it cannot be used

At present, the soldering process is generally used to meet this low temperature requirement. Since the electrode size of the battery to be welded is extremely small, usually no more than 1mm wide, the molten solder easily flows to the surface and side walls of the battery, causing ablation of the battery grid and sidewalls. The short circuit of the wall makes the operation very difficult. Once there is a welding error, it will directly lead to the scrapping of the expensive thin-film gallium arsenide battery, and the loss is huge.

Moreover, thin-film gallium arsenide batteries generally need to be packaged before use. The packaging process will cause the soft interconnection sheet to be bent and attached to the side wall of the battery at the edge of the battery, resulting in "disconnection" between the interconnection sheet and the gallium arsenide layer and the bonding metal layer. Overlapping” short circuit, in order to prevent side wall short circuit caused by solder overflow and interconnection lap, the side of the battery main grid line needs to be protected by complex side wall insulation, which greatly increases the difficulty of battery welding operation

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