Layered Structure Na₂Ti₃O₇ as a Promising Anode Material for Sodium‐Ion Batteries

Abstract

Sodium‐ion batteries (SIBs), as next‐generation energy storage devices, can be made by a similar production process to lithium‐ion batteries (LIBs). The key to accelerating their commercialization is to discover appropriate high‐performance electrode materials with low cost, nontoxicity, and simple synthetic features. Herein, layered‐structure Na 2 Ti 3 O 7 , with the advantages of appropriate charge/discharge plateaus, superior stability, environmental friendliness, and ease of preparation using cheap raw materials, is selected for assembly in full‐cell battery packs to evaluate its suitability for practical application. When evaluated in a coin cell, it has a capacity of 77.2 mAh g −1 at 1 A g −1 after 10 000 cycles with capacity retention of 99.9%, demonstrating its excellent stability. In the case of a soft‐pack battery, it retains 22.3 mAh g −1 at 0.1 A g −1 and 18.1 mAh g −1 at 0.05 A g −1 after 50 cycles. After cycling, there is no sodium dendrite formation or active material shedding, further confirming its safety in practical application. Therefore, Na 2 Ti 3 O 7 as another intercalation/deintercalation mechanism material has application potential in the future.