New Ni 0.5 Ti 2 (PO 4 ) 3 @C NASICON‐type Electrode Material with High Rate Capability Performance for Lithium‐Ion Batteries: Synthesis and Electrochemical Properties

Ni 0.5 Ti 2 (PO 4 ) 3 /C NASICON‐type phosphate is introduced as a new anode material for lithium‐ion batteries (LIBs). Ni 0.5 Ti 2 (PO 4 ) 3 /C was synthesized through the sol–gel route and delivered some remarkable electrochemical performances. Specifically, the Ni 0.5 Ti 2 (PO 4 ) 3 /C electrode demonstrates a high rate capability performance and delivers high reversible capacities ranging from 130 mAh g −1 to about 111 mAh g −1 at current rates ranging from 0.1 C to 5 C in the voltage window of 1.85–3 V (vs. Li + /Li). In the same voltage range, the material reaches an initial capacity of 105 mAh g −1 with a capacity retention of about 82 % after 1000 cycles at the high current rate of 10 C. The electrodes are also tested in the wider voltage range of 0.5–3 V (vs. Li + /Li) and show good reversibility and rate capability performance. Moreover, the Ni 0.5 Ti 2 (PO 4 ) 3 /C electrodes enable fast Li + diffusion (in the order of 10 −13  cm 2  s −1 ) compared with other NASICON‐type materials. As a result, a first discharge capacity of 480 mAh g −1 is reached.