P3-type K0.5Mn0.72Ni0.15Co0.13O2 microspheres as cathode materials for high performance potassium-ion batteries

Yolk–Shell P3‐Type K0.5[Mn0.85Ni0.1Co0.05]O2: A Low‐Cost Cathode for Potassium‐Ion Batteries

“…The Rietveld refinement shows that the YS-KMNC has a well-ordered layered structure (as illustrated in Figure 1i, P3-K 0.5 Mn 0.85 Ni 0.1 Co 0.05 O 2 ) with the lattice parameters a = 2.868 Å and c = 21.113 Å, consistent with previous reports. [26,27] The XRD pattern of the conventional KMNC is shown in Figure S2, which is identical to that of the YS-KMNC, thus confirming identical crystal structures for both. Figure 1j depicts the typical yolk-shell structure and the corresponding element maps.…”

“…Figure 2f and Table S2 also present the comparison of cycle stability, average voltage, and electrolyte between YS-KMNC and other layered cathode materials for PIBs. [13,14,27,30,31,41,42,[44][45][46][47] It is obvious that YS-KMNC has a higher capacity retention and an excellent cycling stability, which confirms the superiority of the yolk-shell structure design. From the above discussion, it is clear that the YS-KMNC delivers an outstanding energy storage performance not only in cycle stability but also in capacity and energy density.…”

“…Moreover, in order to evaluate the advantages of the KMNC with the yolk-shell structure for potassium storage, we compared its specific capacity, average voltage, and energy density with those of many cathode materials reported in the literature (Figure 2e and Table S2). [6,9,13,26,27,31,[33][34][35][36][37][38][39][40][41][42][43][44][45][46][47] Apparently, although some properties of YS-KMNC are inferior to those of other types of cathode materials (vanadium-based oxide, organic and Prussian blue and its derivatives), the YS-KMNC exhibits a more balance performance with remarkable capacity, high average voltage, and outstanding energy density. Generally speaking, the vanadium-based cathodes support a much higher operating voltage, but their strong toxicity greatly limits their application.…”

Electrochemical Overview: A Summary of ACoxMnyNizO2 and Metal Oxides as Versatile Cathode Materials for Metal‐Ion Batteries

“…Deng et al synthesized a P3-type K 0.5 Mn 0.72 Ni 0.15 Co 0.13 O 2 microsphere cathode that can achieve a high energy density per volume and enhanced ion diffusion to improve the rate capability kinetics due to the smaller particle sizes. [250] The rate capability is 57.9 mAh g −1 at 500 mA g −1, and 85.0% of the capacity is retained over 100 cycles 50.0 mA g −1 , which drops to 75.0% over 300 cycles at 200 mA g −1 . Although lowering the current rate to 10 mA g −1 allows for a higher capacity of 82.5 mAh g −1 , it causes a decline in capacity retention.…”

Potassium-ion batteries: outlook on present and future technologies

“…The capacity retention rate after 350 cycles is 78% at the current density of 100 mA•g -1 . This strategy by constructing microspheres to withstand volume expansion has also been applied to P3 type layered K0.5Mn0.72Ni0.15Co0.13O2, 128 which could improve the capacity retention rate by 28% after 300 cycles at 200 mA g -1 as compared to the bulk-like samples.…”