Positive electrode grid wire structure of a solar cell

Abstract

The invention discloses a positive pole grid line structure of a solar cell piece. The positive pole grid line structure comprises a plurality of metal wire grid lines. The metal wire grid lines are connected in series with a plurality of long-strip contact electrodes. The contact electrodes are formed by sintering after being printed through silver slurry, and the length of the contact electrode is 50 mum-2mm. The intersection angle between the contact electrodes connected to the same metal wire grid line and the metal wire grid line is 90+ / -5 degrees. With the positive pole grid line structure, the total area occupied by the grid lines can be controlled, the shading area of the grid lines can be reduced, the metal wire grid lines can be aligned with the contact electrodes conveniently, the grid line electrode is guaranteed to be in good ohmic contact, good current collection is guaranteed, and the photoelectric conversion efficiency of the solar cell piece is improved.

Description

technical field [0001] The invention relates to the field of solar cells, in particular to a front electrode positive grid line structure. Background technique [0002] Solar cell grid lines are generally made of silver paste, which is printed on the front of the solar cell through a specific screen, and then dried and sintered at high temperature. Since the grid lines are made of opaque metal materials, which directly affect the light transmission area of ​​the battery surface, in order to minimize the shading effect, the total area occupied by the grid lines must be controlled as much as possible. The cross-sectional area of ​​the grid line determines its conductivity. From the perspective of conductivity, a thicker grid line has better conductivity, and a too thin grid line is also easy to break. [0003] In order to control the total area occupied by the grid lines, silver paste points can be used as contact electrodes, and then a number of silver paste points can be co...

AI Technical Summary

Problems solved by technology

However, since a single wire grid wire generally needs to be connected in series with many (dozens, even hundreds) of silver paste points, the wiring positioning of the wire grid wire needs to be very precise, that is, the wiring of the wire grid wire must be aligned. Accurate every silver paste point, otherwise it will deviate from the silver paste point, or cannot be in reliable contact with the silver paste point, thus affecting the current collection

[0004] Especially when the positive grid structure of the entire solar cell is a mesh structure, the positioning requirements for the wire grid will be greatly improved. If there is a systematic deviation in the positioning of the wire grid, it will cause a large number of wire grids and silver paste spots. Unreliable contact, even a large number of wire grid lines deviate from the silver paste points, seriously affecting current collection and causing solar cells to be scrapped

[0005] Therefore, in order to ensure the alignment of the wire grid lines and the silver paste points during the wiring process, the requirements for the equipment are very high, and the process cost will also increase.

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