High-Tap-Density Fe-Doped Nickel Hydroxide with Enhanced Lithium Storage Performance.

Nickel hydroxide has attracted much attention as an anode material for lithium-ion batteries (LIBs) due to its high specific capacity, low cost, and easy preparation. However, the poor cycling stability greatly hampers its application. Herein, Fe-doped nickel hydroxide powders with a high tap density (2.16 g cm) are synthesized by a simple chemical co-precipitation method. Compared to undoped nickel hydroxide, this Fe-doped nickel hydroxide exhibits better lithium storage activity, enhanced cycling stability and rate capability, and improved electrochemical reaction kinetics. As an anode material for LIBs, the Fe-doped nickel hydroxide delivers a specific discharge capacity of 1080 mA h g at 200 mA g after 30 cycles, which is almost twice that (519 mA h g) of undoped nickel hydroxide; at a high current density of 2000 mA g, Fe-doped nickel hydroxide shows a specific capacity of 661 mA h g, significantly higher than that (182 mA h g) of undoped nickel hydroxide. Kinetic analysis reveals that Fe doping decreases the electrochemical reaction resistance and improves the lithium ion diffusivity in a nickel hydroxide electrode.