Large area solar cells with efficiency exceeding 19 in pilot series designed for conventional module assembling

摘要

Performance, reliability and cost are the key parameters in terms of wafer material, solar cell design and module fabrication to transfer a new solar cell concept into production. In this paper we present results based on pilot series of large area (156 mm x 156 mm wafer format) passivated emitter and rear solar cells on Czochralski grown boron doped wafers. Median efficiencies above 19% averaged over 50 wafer batches are received. These high-efficiency cells benefit from a passivated lowly doped industrial emitter on the front side, a seed and plate front side metallization and a dielectric passivated rear side using local contacts for rear side contacting. In order to optimize cell performance in a large-scale solar cell production a careful selection of the Cz silicon material is mandatory taking into account the electrical quality along the whole ingot. Solar cell results are presented before and after light-induced degradation using adjacent material along the complete ingot of different material supplier. Our passivated emitter and rear cells are conventionally solderable and can be integrated into a standard module assembling. The stability of our high-efficiency solar cells is shown by fabricating mini-modules that successfully pass standard climate chamber tests.