The present invention provides a method for forming a black electrode by performing sintering at a temperature in the range of 500-600° C. after applying a lead-free black conductive composition to a substrate. The aforementioned black electrode comprises a binder comprising a crystallized glass component. The aforementioned black conductive composition comprises conductive particles of black RuO2, lead-free black ruthenium-based polyoxide, and mixtures thereof in an amount of 4-30 wt %, based on the total weight of the composition, a lead-free non-conductive black oxide in an amount of 0-30 wt %, based on the total weight of the composition, and a lead-free bismuth-based glass binder in an amount of 10-50 wt %, based on the total weight of the composition.