Abstract: 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.

Key words: 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.