Na₂Ru_1−xMn_xO₃ as the cathode for sodium-ion batteries

Abstract

A suitable Mn doping (x = 0.1) enhances the kinetics and structural stability of Na2RuO3, generating a superior electrochemical performance.

A New Approach to Stable Cationic and Anionic Redox Activity in O3‐Layered Cathode for Sodium‐Ion Batteries

“…Based on our findings, we can conclude that the Ni 2+ /Ni 3+ and O 2− /O 1− redox processes are responsible for the charge compensation mechanism in Na[Ni 2/3 Ru 1/3 ]O 2 , where the low plateaus are mainly governed by the cationic redox reaction and the higher plateau is mainly governed by the anionic oxygen redox reaction (Figure 10a). We compared the energy-density of O3-Na[Ni 2/3 Ru 1/3 ]O 2 with those of reported oxygen-redoxassisted O3-compounds, [38,40,41,[50][51][52][53][54][55] including the very recent work by Tarascon et al [56] (Figure 10b; and Table S3, Supporting Information). Apart from the high discharge capacity of about 190 mAh g -1 with an average operation voltage of 2.5 V (≈475 Wh (kg-oxide) −1 ) for the O3 type Na[Li 1/3 Mn 2/3 ]O 2 , the evolution of O 2 gas associated with migration of Li toward Na layers during the first charge is the urgent issue to be resolved, because such oxygen residue is inclined to form sodium carbonates as a CEI layer and may arise safety concern when overcharged in real systems.…”

Sodium diffusion and dynamics in Na2Ti3O7: neutron scattering and ab initio simulations

“…However, they can be used for applications where energy density requirements are not as stringent, 7 and may be commercially viable. 8–12 The first sodium–sulfur battery was developed after the discovery of the high-temperature ionic conductor β-alumina, NaAl 11 O 17 . 13 Since then, many Na-ion conductors have been discovered, 14–17 including the sulfide compounds 18–20 that exhibit very high ionic conductivity suitable for application in batteries.…”

“…The energy density of sodium-ion batteries is some 30 % lower 6 than that of lithium-ion batteries. However, they can be used for applications where energy density requirements are not as stringent 7 , and may be commercially viable [8][9][10][11][12] . The first sodiumsulfur battery was developed after the discovery of the high-temperature ionic conductor β-alumina,…”

Highly Electrochemically‐Reversible Mesoporous Na2FePO4F/C as Cathode Material for High‐Performance Sodium‐Ion Batteries

“…The larger ionic radius of sodium ion (1.02 Å) compared to lithium ion (0.76 Å), however, has been regarded as the greatest challenge to hinder the performance improvement of sodium‐ion batteries . In the past ten years, a lot of works focused on seeking for appropriate Na + ‐host materials, such as transition‐metal oxides, phosphates, and ferrocyanides . Among them, the Fe‐based phosphate is one of the most concerned cathode materials due to its low cost and abundant resources .…”