"Z" -shaped pattern slotting structure applicable to thin-sheet PERC battery

Abstract

The present invention discloses a "Z" -shaped pattern slotting structure applicable to a thin-film PERC battery. The "Z" -shaped pattern slotting structure comprises a silicon substrate, a passivationfilm arranged on the back surface of the silicon substrate, and slotted lines arranged on the passivation film; the slotted lines comprise a plurality of equally spaced horizontal laser slots and a plurality of equally spaced vertical laser slots; the horizontal laser slots and the vertical laser slots have the same length; the horizontal laser slots and the vertical laser slots are connected endto end to form "Z" -shaped slotted lines; a plurality of slotted lines are equidistantly arranged on the surface of the passivation film. According to the slotting structure of the passivation film on the back surface of the PERC solar battery provided by the present invention, the aluminum paste on the back surface of the battery is in good contact with the silicon wafer, and the battery efficiency is slightly improved, efficiency improvement is more reflected in the increase of the open-circuit voltage and the filling, especially for thin silicon wafers; and the crushing rate of the slottedpattern batteries is reduced, and the warpage is reduced.

Description

technical field [0001] The invention relates to the technical field of photovoltaic cells, in particular to a "Z" pattern slotting structure suitable for sheet PERC cells. Background technique [0002] Improving the efficiency of solar cells and reducing costs are the two major themes of photovoltaic development. The conventional aluminum back field is severely recombined on the back, and further improvement in efficiency is very limited. However, coating a passivation film on the back can greatly reduce the recombination of the back surface and improve the minority carrier lifetime. The battery efficiency is greatly improved. [0003] The passivation film is non-conductive and insulating, and the back is made of aluminum paste. It is necessary to slot the passivation film on the back to draw out the current. The design of the slot pattern has a great influence on the electrical performance of the battery. In the prior art, the application number is "201621361451.9". The gr...

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Problems solved by technology

However, the grooved structure of the rear passivation film mentioned above is unreasonable for thin slices, which will lead to more debris and higher warpage of the cell.

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