Novel Solid-State Sodium-Ion Battery with Wide Band Gap NaTi₂(PO₄)₃ Nanocrystal Electrolyte

Abstract

NaTi 2 (PO 4 ) 3 (NTP), a well-known anode material, could be used as a solid wide-band gap electrolyte. Herein, a novel solid-state sodium-ion battery (SSIB) with the thickness of electrolyte up to the millimeter level is proposed. The results of the difference in charge density investigated by the first-principles calculations imply that using the NTP nanocrystals as electrolytes to transport sodium ions is feasible. Moreover, the SSIB exhibits a high initial discharge capacity of 3250 mAh g –1 at the current density of 50 mA g –1 . As compared with other previously reported SSIBs, our results are better than those reported and suggest that the NTP nanocrystals have potential application in SSIBs as solid electrolytes.

The Progress in the Electrolytes for Solid State Sodium‐Ion Battery

“…The solid batteries using NTP performed high initial discharge capacity of 3250 mAh g −1 at the current density of 50 mA g −1 . [ 141 ] Na 2 ZnSiO 4 ‐Py 14 TFSI hybrid solid electrolyte was prepared and achieved conductivity of 5.0 × 10 −3 S cm −1 at 225 °C, the activation energy of hybrid solid electrolyte were decreased and it was primarily due to the diffusion of mobile ions instead of ionic hopping as per in Pristine Na 2 ZnSiO 4 . [ 142 ] A new kind of hexagonal Na 5 YSi 4 O 12 was synthesized by a two stepped solid‐state reaction, delivering room‐temperature ionic conductivity of 1.59 × 10 −3 S cm −1 and activation energy of 0.20 eV, which were benefited from the inherent 3D Na + transport pathway and optimized synthesis conditions in favor of achieving a densificated SE pellet.…”

“…c) Electric charge density difference of the crystal plane (−100) of the NTP crystal attached with a local enlargement map. (a-c) Reproduced with permission [141]. Copyright 2021, American Chemical Society.…”