Main grid silver paste for silicon solar cell and preparation method thereof

Abstract

The invention provides main grid silver paste for a silicon solar cell and a preparation method of the main grid silver paste, the main grid silver paste for the silicon solar cell has good auxiliary grid matching capability and high main grid line stripping strength, the main grid silver paste for the silicon solar cell comprises silver powder, glass powder and an organic carrier, and the total weight of the main grid silver paste for the silicon solar cell is 100%. The silver paste comprises the following components in percentage by weight: 80.0%-90.0% of silver powder; 0.3%-2.0% of glass powder; and 8.0%-15.0% of an organic carrier. The main grid silver paste for the silicon solar cell can be well matched with step-by-step printing of different types of cell pieces and can also be matched with different types of auxiliary grid silver paste, after matching, the opening voltage is high, the photoelectric conversion efficiency is high, the main grid peeling strength is high, and the service life is long. And the requirements of the current different types of sizing agents and battery pieces for printing the main grid sizing agents step by step can be well met.

Description

technical field [0001] The invention belongs to the field of silicon solar cells, in particular to a main grid conductive silver paste for silicon solar cells and a method for preparing the main grid conductive silver paste for silicon solar cells. technical background [0002] Crystalline silicon solar cells are silicon-based semiconductor devices that use the photoelectric effect of semiconductors to convert light energy into electrical energy. According to the type of silicon crystal and the characteristics of PN junctions, crystalline silicon solar cells can be divided into P-type polycrystalline silicon cells and P-type monocrystalline silicon cells. , P-type Perc monocrystalline silicon cells, P-type Se-Perc monocrystalline silicon cells, N-type polycrystalline silicon cells, N-type monocrystalline cells and N-type topcon cells, etc. From the current development situation, the current mainstream is P-type Se -Perc monocrystalline silicon cell and N-type topcon cell, an...

AI Technical Summary

Problems solved by technology

Silicon solar cell conductive silver paste is generally composed of three parts: silver powder, glass powder, and organic carrier. The organic carrier mainly plays a role in ensuring the screen printing effect of the silver paste. After the silver paste is printed, the silver powder and glass powder are responsible for building the integrity of the battery surface during sintering The role of the grid wire electrode, the silver powder mainly plays the role of forming a channel for electron collection and electron export, the glass powder mainly plays the role of helping to burn the silver powder, etching the insulating anti-reflection film on the surface of the battery and forming the contact between the PN junction and the silver grid line channel, so even though the content of glass is very small in the silver paste of silicon solar cells, its role is extremely important, and it directly affects the photoelectric conversion efficiency of the cell after printing the grid electrode and the strength of the busbar glass

However, with the development of silicon solar cell technology, it is found that it is difficult to combine high efficiency and high busbar glass strength with a single silver paste, so a new printing method of battery silver paste has been developed, which is step-by-step printing , that is, the main grid line is printed on the surface of the battery, and then the printing method of the sub-grid line is completed. Two different pastes are selected and printed on the surface of the silicon solar cell by step-by-step printing, which realizes the photoelectric conversion of the battery. Taking into account the efficiency and the strength of the grid glass, the silver paste for the main grid of silicon solar cells was born. Since the birth of the silver paste for the main grid of silicon solar cells, the method of step-by-step printing of the main and auxiliary grid silver paste has become the current Mainstream, at least 80% of customers have adopted the step-by-step printing method of main and auxiliary grid silver paste for silicon solar cell grid printing, so the development of busbar silver paste with excellent performance has important practical application value and economic value