Gas-solid interfacial modification of oxygen activity in layered oxide cathodes for lithium-ion batteries.

ABSTRACT: Lattice oxygen can play an intriguing role in electrochemical processes, not only maintaining structural stability, but also influencing electron and ion transport properties in high-capacity oxide cathode materials for Li-ion batteries. Here, we report the design of a gas-solid interface reaction to achieve delicate control of oxygen activity through uniformly creating oxygen vacancies without affecting structural integrity of Li-rich layered oxides. Theoretical calculations and experimental characterizations demonstrate that oxygen vacancies provide a favourable ionic diffusion environment in the bulk and significantly suppress gas release from the surface. The target material is achievable in delivering a discharge capacity as high as 301?mAh?g(-1) with initial Coulombic efficiency of 93.2%. After 100 cycles, a reversible capacity of 300?mAh?g(-1) still remains without any obvious decay in voltage. This study sheds light on the comprehensive design and control of oxygen activity in transition-metal-oxide systems for next-generation Li-ion batteries.

SUBMITTER: Qiu B 

PROVIDER: S-EPMC4932185 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature