Insights into the structural effects of layered cathode materials for high voltage sodium-ion batteries

Abstract

We reported the interplay between phase structures, interfacial microstrain and electrochemical properties of layered cathodes.

Recent Progress of Layered Transition Metal Oxide Cathodes for Sodium‐Ion Batteries

“…Its instability in air, however, still limits its application . Na x Ni 1/3 Co 1/3 Mn 1/3 O 2 with a mixed P2/O3/O1 structure exhibits better electrochemical performance and thermal stability than the one with P2/O3 phase integration or with a single P2 phase . This P‐/O‐type intergrowth inhibits the irreversible P2–O2 phase transformation during cycling and improves the structural stability of the O3 and O1 phases, which was demonstrated by an in‐operando high energy XRD study (Figure b).…”

“…Copyright 2017, American Chemical Society. b) In situ XRD patterns of Na x Ni 1/3 Co 1/3 Mn 1/3 O 2 with P2/O3/O1 structure during the first cycle between 2.0 and 4.4 V. Reproduced with permission . Copyright 2017, Royal Society of Chemistry.…”

Readiness Level of Sodium‐Ion Battery Technology: A Materials Review

“…Passerini and co-workers [215] systematically studied the Ni-to-Fe ratio effect in Na x MO 2 (with M = Ni, Fe, and Mn) in suppressing Mn dissolution and improving material stability. [36] Na x Ni 1/3 Co 1/3 Mn 1/3 O 2 with intergrowth P2/O3/O1 structures showed a better stability and a suppression of interfacial microstrain during high voltage charging. 6 Apparently the only efficient way to increase reversibility excluding deleterious phase transitions is to narrow the operative potential window.…”

“…[32] Provided the plethora of promising anode and cathode materials so far proposed for nonaqueous sodiumion rechargeable batteries, many research groups started investigating whole sodium-ion cell (full-cell). Among the compounds suitable as cathodes, layered O3 and P2-type transition metal oxides [35,36] and transition metals polyanion [37][38][39] obtained remarkable attention, and so far efforts have been focusing on crystalline phases stability, achieved via doping [40] or selecting the most suitable final crystalline phase by finely tuning the synthetic conditions. On the contrary fully ion-dependent cells, inspired by lithiumion "rocking chair" set up, [33] are preferred.…”

“…Due to the higher reactivity of sodium, its tendency in forming dendrites and its low melting point (97 °C), several safety issues are connected to the development of a metallic sodium-based full battery. [36] On the anode side, instead, more than one single chemistry became appealing and worth to be investigated. In this configuration anodic materials whose electrochemical activity is based on intercalative or pseudocapacitive [34] behavior, are employed in place of metallic sodium.…”