Low-melting point glass powder for silver pastes on fronts of silicon solar cells and preparation method of glass powder

Abstract

The invention discloses low-melting point glass powder for silver pastes on fronts of silicon solar cells and a preparation method of the glass powder. The low-melting point glass powder is mainly used as a binder for the silver pastes on the fronts of the silicon solar cells and comprises the following components in percentage by weight: 30-60% of Bi2O3, 1.5-18% of B2B3, 1-13% of ZnO, 1-15% of Al2O3, 0.1-6% of BaO, 10-45% of TeO2 and 3-25% of SiO2. The preparation method comprises the steps of: (1) weighing to prepare a mixture; (2) adding the mixture into a crucible and adding a cover for smelting; (3) carrying out water quenching on the smelted glass liquid; (4) drying and crushing; and (5) grading the powder. The prepared glass powder is favorable in conductivity, is capable of decreasing the absorption and the reflection of printed grid lines and electrodes to the sunlight and decreasing the shadow loss of contacting the grid lines and the electrode, has relatively low softening point and low thermal expansion coefficient at the same time and is beneficial for improving the photoelectric conversion efficiency and prolonging the service life of the solar cells.

Description

technical field [0001] The invention relates to the technical field of electronic materials, in particular to a lead-free low-melting-point glass powder for front silver paste of crystalline silicon solar cells and a preparation method thereof. Background technique [0002] Photovoltaic industry, as a sunrise industry in the 21st century, has broad prospects for development. It has been widely valued by countries all over the world, and a lot of human and financial resources have been invested in research and development. The key to affecting the efficiency of solar energy utilization is how to improve the conversion efficiency of solar cells. The factors that affect the conversion efficiency of solar cells mainly include the surface reflection loss of the battery, the shadow loss of the contact grid line and the electrode, the non-absorbing optical loss of the long-wave band, the recombination of photogenerated carriers on the surface and body of the semiconductor, and the b...

AI Technical Summary

Problems solved by technology

In addition, the Chinese patent with the publication number CN101483207A discloses an environment-friendly silver conductor paste for the front grid wire electrodes of silicon solar cells, which uses Ba-Zn-B glass powder, which can well melt the anti-reflection of the silicon surface of silicon solar cells. film, so that silver and silicon can be in good contact, so that the battery sheet has excellent photoelectric conversion performance, but the glass powder has more components, the production control is more complicated, the glass softening point is high, and the glass powder particle size is large, which affects the slurry. The sintering performance of the material

[0004] In the application publication number CN102126829A Chinese patent discloses a lead-free glass frit, its softening temperature, melting temperature, thermal expansion coefficient, etc. The photoelectric conversion rate reaches 17.5%, but it does not consider the absorption of light by printed grid lines and electrodes and the reflection of light by the shadow of electrode grid lines, and does not consider the influence of contact grid lines and electrode shadows on improving light absorption efficiency and conversion efficiency.

At the same time, the patent optimizes the glass powder range of 0.5-5um, and does not consider the uniformity of the particle size distribution and the impact of the span on the penetration of the anti-reflection film, the adhesion between the silver powder and the silicon substrate, and the electrical conductivity.

Images