Fabrication of Nickel Nanosized Powder from LiNiO2 from Spent Lithium-Ion Battery

• Main Authors: Shun-Myung Shin, Dong-Won Lee, Jei-Pil Wang
• Format: Article
• Language: English
• Published: MDPI AG 2018-01-01
• Series: Metals
• Subjects: nickel; nanosized powder; hydrazine; liquid phase reduction; PVP
• Online Access: http://www.mdpi.com/2075-4701/8/1/79

In this study, a fabrication of nickel nanoparticles from LNO(LiNiO2), which is a cathode active material, was synthesized by the liquid reduction process of NiSO4, obtained through a leaching and purification process. Hydrazine monohydrate (N2H4·H2O) was used as a liquid reducing agent and it was added to NiSO4 at a volume ratio of NiSO4:N2H4·H2O = 10:3 and reacted for 10 min to synthesize the nickel hydrazine complex. Sodium hydroxide was added to the nickel hydrazine complex at the weight ratio of NiSO4:NaOH = 10:1.25–1.5 and the reduction reaction was performed at 80 °C for 15 min to synthesize nickel particles. Synthesized nickel particles were agglomerated and had a mean size of 200 nm to 300 nm. Ultrasonic dispersion, which is a physical dispersion method, was conducted. The nickel had particles of 100 nm or less when dispersed for 2 h at an ultrasonic intensity of 40 kHz. In order to prevent the agglomeration of the dispersed particles again, polyvinylpyrrolidone (PVP), an interfacial stabilizer, was added to stabilize the dispersed particles. It was confirmed that the nanoparticles were stably retained when PVP was added in an amount of 1 to 2 wt % based on the weight of the nickel. The purity of nickel recovered was found to be 99.62 wt %.