Patent ID: 8871116

Claim:
A water-based conductive ink composition comprising: an aqueous carrier; acid-washed graphite particles; carbon black particles; and at least one stabilizing ingredient that suspends the acid-washed graphite particles and the carbon black particles in the aqueous carrier, the at least one stabilizing ingredient being selected from the group consisting of dispersants, binders, defoamers, and combinations thereof, wherein: the water-based conductive ink composition has a total elemental contaminant level of less than 100 ppm, based on the total weight of the water-based conductive ink composition; the total elemental contaminant level is the total concentration of aluminum, calcium, cobalt, chromium, copper, iron, potassium, manganese, magnesium, nickel, and zinc in the water-based conductive ink composition; and at least 90 wt. % of the acid-washed graphite particles and the carbon black particles, based on the combined weight of the acid-washed graphite particles and the carbon black particles, have particle sizes less than 10 μm.