Crystalline silicon solar cell positive silver paste doped with organic silver and preparation method thereof

Abstract

The present invention discloses a crystalline silicon solar cell positive silver paste doped with organic silver. The crystalline silicon solar cell positive silver paste doped with organic silver comprises the following components, parts by mass: 1-10 parts of organic silver, 75-90 parts of silver powder, 1-5 parts of an inorganic binder, and 6-12 parts of an organic binder. The present inventionfurther discloses a preparation method of a crystalline silicon solar cell positive silver paste doped with organic silver. The organic silver can be uniformly dispersed in the organic binder is decomposed into silver at a temperature of 200-350 DEG C, the decomposed silver can be more uniform and completely fills between silver particles to form a tight conductive channel so as to reduce the electrode resistance and improve the photoelectric conversion efficiency, the surface of the silver powder is coated with the organic silver to properly reduce the high-temperature melting rate of the silver powder to allow a skeleton formed by stacking silver powder particles not to be collapsed and obtain a large depth-width ratio so as to improve the photoelectric conversion efficiency. The softening point of the inorganic binder is lower than the melting point of the silver powder, the inorganic binder can be faster to be molten to rapidly coat the surfaces of the silver powder particles, avoid melting of the silver powder in a high temperature and ensure the large depth-width ratio of the product so as to improve the photoelectric conversion efficiency. The crystalline silicon solar cellpositive silver paste doped with organic silver is good in uniformity, small in series resistance, large in depth-width ratio and high in photoelectric conversion efficiency.

Description

technical field [0001] The invention belongs to the technical field of silver paste for electrodes of crystalline silicon solar cells, and in particular relates to a front silver paste of crystalline silicon solar cells doped with organic silver and a preparation method thereof. Background technique [0002] A crystalline silicon solar cell is mainly composed of a front electrode, a back electrode and a silicon substrate. The series resistance generally consists of the front electrode resistance, the back electrode resistance, the contact resistance between the electrode and the silicon substrate, and the bulk resistance of the silicon substrate. Series resistance is one of the important performance indicators affecting the performance of crystalline silicon solar cells. [0003] The front electrode of the crystalline silicon solar cell is prepared by printing the front silver paste on a silicon wafer coated with a silicon nitride film, and then drying and sintering. The s...

AI Technical Summary

Problems solved by technology

At the same time, it is required that the content of silver powder is generally more than 80%, which is beneficial to obtain lower electrode resistance, but because the content of silver powder is high and the content of organic binder is low, it is usually difficult for a small amount of organic binder to completely disperse the silver powder evenly. This leads to larger fineness and poor uniformity of the slurry, which increases the contact resistance value and thus increases the series resistance

In addition, the silver powder will melt during high-temperature sintering, which will reduce the accumulation height of the silver powder, reduce the aspect ratio of the grid line, and reduce the photoelectric conversion efficiency of the product.