A Fundamental Investigation of Electrochemical Preparation of Battery Grade Nickel Hydroxide
Electrochemical studies on nickel hydroxide have shown that three reduction reactions take place simultaneously at the cathode to reduce nitrate to nitrite, nitrite to ammonium ion and nitrate to ammonium ion. All the three reactions produce hydroxyl ion which raise pH to a level favorable to precipitate Ni(OH)2. Current density, which regulates flow of OH- supply, has prominent effect on the process and products. It determines whether α- or β-Ni(OH)2 would be precipitated and has a direct relationship with size and structure of the product and also with the associated water molecules. Replacement of Ti anode with consumable Ni sheet remarkably improves current efficiency (production rate) and decreases power consumption.
Atsushi Suzuki and G. Sundararajan
B. Ash et al., "A Fundamental Investigation of Electrochemical Preparation of Battery Grade Nickel Hydroxide", Advanced Materials Research, Vol. 117, pp. 15-20, 2010