A method for predicting the likelihood of coagulation of active material particles contained in a slurry for electrode preparation includes measuring rheological properties before and after the slurry is subjected to a shear. The estimation method enables a prediction of filter clogging with a slurry, and thus makes it possible to estimate the likelihood of filter clogging with a slurry without passing the slurry directly through the filter, thereby improving the efficiency of a battery manufacturing process.