Constructing O2/O3 homogeneous hybrid stabilizes Li-rich layered cathodes

作者：Chen, Yafen; Liu, Yanchen; Zhang, Jingchao; Zhu, He^*; Ren, Yang; Wang, Wei; Zhang, Qi; Zhang, Yang; Yuan, Qunhui; Chen, Guo-Xing; Gallington, Leighanne C.; Li, Kaikai; Liu, Xingjun; Wu, Junwei^*; Liu, Qi^*; Chen, Yanan

来源：Energy Storage Materials, 2022, 51: 756-763.

DOI：10.1016/j.ensm.2022.07.016

• Li -rich layered cathodes
• Li -ion batteries
• O2
• O3 hybrid
• Oxygen stacking
• In -situ X-ray diffraction

With the advantages of high energy density and low manufacture cost, lithium-rich layered oxides (LLOs), typically with a layered O3-type structure, are regarded as promising cathodes for lithium-ion batteries (LIBs), but their broad usages are hindered by severe voltage decay over cycling. Although recent progress in O2-type LLOs has aroused interest for their less voltage decay, the critical barrier of unsatisfactory capacity retention has not been overcome yet. To tackle these handicaps, herein we design a new type of LLO (O2/O3-type LLO) with a homogeneous hybrid structure, where the O2 and O3 lattice stacking sequences are arranged alternatively. Benefitting from this novel O2/O3 hybrid structure, the designed material shows greatly improved voltage and capacity stability than that of pure O2-and O3-type LLOs. Revealed by in-situ synchrotron X-ray diffraction and operando differential electrochemical mass spectra, the O2/O3-hybrid LLO cathode shows a more reversible structural evolution, smaller volume change and suppressed oxygen loss during the electrochemical processes. Our approach has initiated a new way to reduce the capacity and voltage decay of LLOs, which endows great promise to the development of high-energy-density LIBs.

• 单位
  天津大学