K+-doped P2-Na0.67Fe0.5Mn0.5O2 cathode for highly enhanced rate performance sodium-ion battery

Enhanced Rate Performance and Available Specific Capacity of the O3-NaNi0.5Mn0.3Ti0.2O2 Cathode by K Substitution for Sodium-Ion Batteries

“…The discharge specific capacity of the KNMT50 is significantly higher than that of the NMT0 at any rate. This may be due to the fact that the distance of the Na layer increased and the increased electrochemical activity of elemental Ni after K doping, so that more Na + can be de-embedded and involved in the galvanic reaction of the electrode, leading to an increase in the available specific capacity. ,,,− Moreover, the wider interlayer spacing will promote diffusion of Na + and thus improve the rate performance. However, the available specific capacity is somewhat reduced when the amount of K doping is 0.075.…”

“…At present, numerous studies on the K doping modification of P2-type layered oxides have demonstrated that K doping is advantageous for enhancing the rate capability of the materials. ,− In contrast, there are few studies on doping K in the O3-type crystal structures. In this work, we modify the O3-NaNi 0.5 Mn 0.3 Ti 0.2 O 2 material by K doping.…”

Toward the High‐Voltage Stability of Layered Oxide Cathodes for Sodium‐Ion Batteries: Challenges, Progress, and Perspectives

“…Furthermore, the introduction of cations into the sodium layers of LOCs has gained increasing attention in recent decades. Cations such as Li + , [ 109 ] Mg 2+ , [ 110 ] K + , [ 111 ] and other candidate non‐active cations can act as pillars to mitigate the significant expansion or contraction of the material under high voltage. Li's group successfully embedded large‐sized K + ions into the Na sites of P2‐phase Mn‐based LOCs (Figure 8d).…”

Doping Engineering in Electrode Material for Boosting the Performance of Sodium Ion Batteries

“…At a doping level of 0.05 K + , the cathode demonstrates notable cycling stability at 1 C, maintaining 70% of its capacity after 100 cycles. 92 Conducting dual-site doping of K + and Cu 2+ in Na 2/3 [Ni 1/3 Mn 2/3 ]O 2 , Ouyang et al achieved lattice expansion through K + doping and enhanced air stability due to the high redox potential of Cu 2+ /Cu 3+ . The resultant multiple-layer oriented P2−K 0.05 Na 0.67 Mn 0.6 Ni 0.3 Cu 0.1 O 2 exhibited exceptional rate performance, rapid Na + transport, and superior cycling stability, retaining 91.2% of its capacity at a high current density of 1 A g −1 after 1800 cycles.…”