P3‐Type Layered Sodium‐Deficient Nickel–Manganese Oxides: A Flexible Structural Matrix for Reversible Sodium and Lithium Intercalation

• DOI: 10.1002/cplu.201500215
• Publication Date: 2015-07-28T01:37:26Z
• Authors: Maria Kalapsazova; Gregorio F. Ortiz; Jose L. Tirado; Oleksandr Dolotko; Ekaterina Zhecheva; Diana Nihtianova; Lyuben Mihaylov; Radostina Stoyanova
• Keywords: Superstructure

Sodium-deficient nickel-manganese oxides exhibit a layered structure, which is flexible enough to acquire different layer stacking. The effect of stacking on the intercalation properties P3-Nax Ni0.5 Mn0.5 O2 (x=0.50, 0.67) and P2-Na2/3 Ni1/3 Mn2/3 , for use as cathodes in sodium- lithium-ion batteries, examined. For P3-Na0.67 large trigonal superstructure with 2√3 a×2√3 a×2 c observed, whereas there reduced lattice parameters. In sodium cells, P3 P2 phases intercalate reversibly at well-expressed voltage plateau. Preservation P3-type structure during determines improving cycling stability phase within an extended potential range, comparison that phase, P2-O2 transformation has been found. Between 2.0 4.0 V, display excellent rate capability. lithium intercalates lithium, accompanied by P3-O3 structural transformation. situ generated O3 containing simultaneously, specific profile . does not any reversible intercalation. demonstrates higher capacity lower rates cells operates better rates. These findings reveal unique ability sodium-deficient application low-cost electrode materials both batteries.