Li/Na Ion Intercalation Process into Sodium Titanosilicate as Anode Material

A natisite structured material, Na 2 TiSiO 5 , has been investigated as anode for lithium‐ and sodium‐ion batteries. The results show that Na 2 TiSiO 5 can deliver a capacity of 260 mAh g −1 with good reversibility when used as anode in Li‐ion batteries. In contrast to the conversion reaction mechanism observed for its analogue Li 2 TiSiO 5 , a solid‐solution type intercalation mechanism is found for the lithiation/delithiation process of Na 2 TiSiO 5 . Lithium intercalation occurs through a three‐dimensional diffusion path after crossing an energy barrier around 1.0 eV. Sodium‐ions could only migrate through a one‐dimensional channel after overcoming a much higher energy barrier of 1.8 eV, which solely delivers a reversible capacity of 40 mAh g −1 for sodium‐ion storage.