"Persistent State-of-Charge Heterogeneity in Relaxed, Partially Charged Li1−xNi1/3Co1/3Mn1/3O2 Secondary Particles"

William E. Gent : Yiyang Li, Sungjin Ahn, Jongwoo Lim, Yijin Liu, Anna M. Wise, Chirranjeevi Balaji Gopal, David N. Mueller, Ryan Davis, Johanna Nelson Weker, Jin-Hwan Park, Seok-Kwang Doo, William C. Chueh; Advanced Materials, 05/17/16.

Additional Authors: Yiyang Li, Sungjin Ahn, Jongwoo Lim, Yijin Liu, Anna M. Wise, Chirranjeevi Balaji Gopal, David N. Mueller, Ryan Davis, Johanna Nelson Weker, Jin-Hwan Park, Seok-Kwang Doo, William C. Chueh

Abstract:

Ex situ transmission X-ray microscopy reveals micrometer-scale state-of-charge heterogeneity in solid-solution Li1−xNi1/3Co1/3Mn1/3O2 secondary particles even after extensive relaxation. The heterogeneity generates overcharged domains at the cutoff voltage, which may accelerate capacity fading and increase impedance with extended cycling. It is proposed that optimized secondary structures can minimize the state-of-charge heterogeneity by mitigating the buildup of nonuniform internal stresses associated with volume changes during charge.