Author: Haidong Liu
Title: High-Performance Single Crystal Ni-rich LiNi0.8Mn0.1Co0.1O2 cathode materials Enabled by an Ultrathin Surface Coating
Affiliation: Uppsala University
Abstract
LiNi0.8Mn0.1Co0.1O2 (NMC811), one of the most promising cathode materials to develop high energy-density lithium ion batteries, has been extensively investigated because of the high reversible capacity and lower cost. However, its practical application is hindered by the limited cycle life due to the structural instability, microcracks formation and severe electrolyte degradation at the high upper cut-off voltage. In order to overcome these issues, in this work, single crystal NMC811 materials have been successfully synthesized and further modified.
The single crystalline NMC811 sample shows around 5 μm in size and polyhedral shape. Furthermore, an ultrathin surface coating (~2 nm) was built on the surface of this single crystal material. As a result, this surface-coated single crystal NMC811 material exhibited a higher reversible capacity and significant improvement of cycling stability. The capacity retention reached 86 % after 300 cycles at 0.5 C between 3 and 4.5 V vs. Li/Li+.