Lattice Engineering on Li 2 CO 3 -Based Sacrificial Cathode Pre-lithiation Agent for Improving The Energy Density of Li-Ion Battery Full-Cell.

Developing sacrificial cathode pre-lithiation technology to compensate for active lithium loss is vital for improving the energy density of lithium-ion battery full-cells. Li 2 CO 3 owns high theoretical specific capacity, superior air stability, but poor conductivity as an insulator, acting as a promising but challenging pre-lithiation agent candidate. Herein, extracting a trace amount of Co from LiCoO 2 (LCO), we develop a lattice engineering through substituting Li sites with Co and inducing Li defects to obtain Co-Li 2 CO 3 @LCO, in which both the bandgap and Li-O bond strength have essentially declined. Benefiting from the synergistic effect of Li defects and bulk phase catalytic regulation of Co, the potential of Li 2 CO 3 deep decomposition significantly decreases from typical >4.7 V to ∼4.25 V versus Li/Li + , presenting >600 mAh/g compensation capacity. Impressively, coupling 5 wt% Co-Li 2 CO 3 @LCO within NCM-811 cathode, 235 Wh/kg pouch-type full-cell is achieved, performing 88% capacity retention after 1000 cycles. This article is protected by copyright. All rights reserved.