Inhibition of the P3–O3 phase transition via local symmetry tuning in P3-type layered cathodes for ultra-stable sodium storage

Abstract

Sodium-deficient layered oxide cathode materials such as P3-type Na2/3Ni1/3Mn2/3O2 (P3-NaNM) usually suffer from different kinds of Na+/vacancy ordering and phase transitions upon Na+ extraction/insertion, which result in inferior rate capability...

P3‐Na0.45Ni0.2Mn0.8O2/Na2SeO4 Heterostructure Enabling Long‐Life and High‐Rate Sodium‐Ion Batteries

“…[ 34,49–55 ] Impressively, this full cell maintains 84% and 82.8% capacity retention at 50 mA g −1 and 1000 mA g −1 over 100 and 1000 cycles, respectively (Figure 5f,g). As displayed in Figure 5h, this full cell exhibits superior cycling stability to those of recently reported full‐cell devices, [ 21,34,49,52,55–59 ] achieving the lowest per cycle fades percentage and the highest remains capacity, suggesting promising practical applications in future.…”

“…h) Capacity fading percentage for per cycle comparison plot. (P2-NZNCMO represents [Na 0.67 Zn 0.05 ]Ni 0.18 Cu 0.1 Mn 0.67 O 2 ; [49] NaNM@Zr represents P2type Na 2/3 Ni 1/3 Mn 2/3 O 2 @ZrO 2 ; [56] P3-NaLNMT represents P3-Na 2/3 Li 1/9 Ni 5/18 Mn 1/2 Ti 1/6 O 2 ; [21] ZnFeHCF-2 represents Na x Zn y Fe 1-y [Fe(CN) 6 ]; [52] O3-NNAMO represents O3-NaNi 0.45 Al 0.1 Mn 0.45 O 2 ; [57] P2/O3-NaNMS represents P2/O3-Na 2/3 Ni 1/3 Mn 1/3 Sn 1/3 O 2 ; [34] LLS-NaNCMM represents P2@P3 integrated spinel Na 0.5 Ni 0.1 Co 0.15 Mn 0.65 Mg 0.1 O2; [58] P2-NaMNNb represents Na 0.78 Ni 0.31 Mn 0.67 Nb 0.02 O 2 ; [55] P2-NNCMB represents Na 0.67 Ni 0.3 Co 0.1 Mn 0.6 O 1.94 (BO 3 ) 0.02 . [59] ).…”

“…[1][2][3] In SIBs, cathode materials are critical in determining the cost, co-substitution can inhibit the irreversible P3-O3 phase transitions that occur at high voltages to prevent structural deterioration of P3-Na 2/3 Li 1/9 Ni 5/18 Mn 1/2 Ti 1/6 O 2 . [21] Besides, structural modulation by breaking the cation order to balance the electrostatic interaction has also been confirmed effective in enhancing P3-oxides structural stability. [22,23] Protective layer coating is another tactic that prevents the production of surface byproducts originating from side reactions with electrolytes, thus ensuring the long-term cycling of P3-type materials.…”

Dual Modification of P3-Type Layered Cathodes to Achieve High Capacity and Long Cyclability for Sodium-Ion Batteries

“…This suppression of the phase transition mechanism significantly impedes the gliding of TMO 2 layers within the cathode structure, effectively mitigating the associated volume expansion/contraction and subsequent stress generation. Hence, the structural integrity of the material is preserved, leading to the improved reversibility of electrochemical reactions …”

“…Hence, the structural integrity of the material is preserved, leading to the improved reversibility of electrochemical reactions. 51 Apart from element doping, morphology control was also utilized to improve the electrochemical performance of the P3 cathode. To get insight into the vital role of hollow microrod structure, FEA was employed to examine the desodiationinduced Von Mises stress and corresponding normalized displacement upon deintercalation of Na + for the hexagon-like (HL) and hollow porous microrod (PR) electrodes.…”