为了确保晶硅太阳能电池在拥有较高光电转换效率的同时降低投入成本,本文研究了45wt%的低固相含量状态下不同粒径及振实密度的片状银粉对背面银浆性能的影响。将球形银粉经过不同时间的球磨得到不同粒径的片状银粉。用这四种银粉制成背面银浆并经过印刷烧结形成背电极,研究了粒径、振实密度对背电极烧结膜形态及电性能的影响。结果证明平均粒径为2.5μm的片状银粉具有最高的振实密度,由其制备背电极的烧结膜最为致密,焊接强度达到8.5 N,硅太阳能电池的光电转换效率达到18.09%,可以满足目前背面银浆的商业使用需要。
In an attempt to meet both the highest solar cell conversion efficiency and the lowest cost for backside silver pastes, the effect of flake silver powders with different particle size on performance of backside silver pastes for crystalline silicon solar cells was investigated on condition of low solid contents (45wt%). The flake silver powders with four different sizes were prepared using planetary ball mill. Then the effect of silver powders with different sizes and tap density on morphology as well as electrical performance of sintered membrane were studied when these back silver pastes were printed and further formed back electrodes on solar cells. The results indicated that the flake silver powders with average particle sizes of 2.5 μm have maximum tap density, the back silver electrode made by silver powders mentioned above have the densest surface, the average pull-off force reached 8.5 N and conversion efficiency of solar cell reached 18.09 %, such backside silver paste could meet present business needs.