Tuning local chemistry of P2 layered-oxide cathode for high energy and long cycles of sodium-ion battery.

ABSTRACT: Layered transition-metal oxides have attracted intensive interest for cathode materials of sodium-ion batteries. However, they are hindered by the limited capacity and inferior phase transition due to the gliding of transition-metal layers upon Na⁺ extraction and insertion in the cathode materials. Here, we report that the large-sized K⁺ is riveted in the prismatic Na⁺ sites of P2-Na_0.612K_0.056MnO₂ to enable more thermodynamically favorable Na⁺ vacancies. The Mn-O bonds are reinforced to reduce phase transition during charge and discharge. 0.901 Na⁺ per formula are reversibly extracted and inserted, in which only the two-phase transition of P2 ↔ P'2 occurs at low voltages. It exhibits the highest specif

SUBMITTER: Wang C 

PROVIDER: S-EPMC8050090 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature