Full back electrode contact crystalline silicon solar cell structure and preparation method thereof

Abstract

The invention provides a full back electrode contact crystalline silicon solar cell structure and a preparation method thereof. The full back electrode contact crystalline silicon solar cell structure sequentially comprises an antireflection film / passivation film, a front N+ doping layer, an N-type silicon substrate, a back doping layer, a back passivation film and cell electrodes from top to bottom, wherein the back doping layer is formed by alternately arranging N-type doping regions and P-type doping regions at intervals; each cell electrode comprises local metal electrodes arranged in an array and fine metal guide wires; the local metal electrodes penetrate through the back passivation film; the local metal electrodes and the N-type doping regions and the P-type doping regions on the back surface form ohmic contact; the fine metal guide wires are combined with the local metal electrodes through a conductive bonding material to form local suspended fine grid line electrodes; and electrode leads are arranged at opposite ends of the P-type regions and the N-type regions on the back surface of a cell respectively and are used for exporting collected current. By the full back electrode contact crystalline silicon solar cell structure, the light shade area of grid lines is avoided, so that the conversion efficiency of the cell is improved; and meanwhile, the production cost is reduced by reducing the usage amount of metal paste.

Description

technical field [0001] The invention belongs to the technical field of solar cells, and in particular relates to a structure of a crystal silicon solar cell with full back electrode contact and a preparation method thereof. Background technique [0002] Since the first solar cell was born in Bell Laboratories in 1954, crystalline silicon solar cells have been widely used, the conversion efficiency has been continuously improved, and the production cost has continued to decline. At present, crystalline silicon solar cells account for more than 80% of the total global solar cell market, and the conversion efficiency of crystalline silicon cell production lines has exceeded 20%. The cost of electricity continues to shrink and is expected to be flat in the next few years. As a clean energy source, crystalline silicon solar cells play an increasingly important role in changing the energy structure and alleviating environmental pressure. [0003] If crystalline silicon solar cel...

AI Technical Summary

Problems solved by technology

At present, the electrodes of crystalline silicon solar cells are mostly screen-printed with silver paste to form nearly a hundred fine grids and several main grids. The materials used in this process are expensive, and the silver electrodes will cause 5% to 7% of the surface of the cell. The area forms the shading of light, resulting in resistive loss and recombination loss at the same time

[0004] The back contact battery solves the light shielding problem of the metal grid wire because the metal electrode of the battery is wound back to the back of the battery, but the amount of silver or other conductive metals in the electrode has not been reduced, on the contrary, it is slightly higher than that of conventional batteries. Increase

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