Construction of the Na_0.92Li_0.40Ni_0.73Mn_0.24Co_0.12O₂ sodium-ion cathode with balanced high-power/energy-densities

Layered P2 type transition metal oxides (TMOs) are considered as the promising cathode candidates for the sodium ion batteries (SIBs). However, the high operating voltage of the P2 cathodes always involves the irreversible phasic transition, which thus compromises the structural stability and practical applications. Through the sustainable recycling of biomass carbon as the sacrificial precursor framework, herein, a Na_0.92Li_0.40Ni_0.73Mn_0.24Co_0.12O₂ cathode with the coexisting P2/O3 phases is reported. By the aid of transmission-mode operando X-ray diffraction, the real-time phasic transition upon the solid-state reaction is precisely tracked. Furthermore, a full cell prototype by pairing the as-fabricated cathode with the anode that developed via a similar sacrificial templating strategy is established. The full cell model renders the simultaneous robust stability, the high energy density of ~218.5 ​Wh kg⁻¹ at a power density of 83 ​W ​kg⁻¹ (0.5C). This biomass-templated strategy demonstrates a precise control over the structural and compositional features of electrodes for the SIBs.