Lattice engineering of Li2NiO2 via metal doping for high-rate prelithiation with suppressed gas evolution

In situ tracking reveals the electrochemical decomposition pathway of Li 2 NiO 2 . • Metal doping stabilizes lattice oxygen and mitigates gas evolution. • Excellent cycling stability: 87% capacity retention at 1 C after 250 cycles. Li 2 NiO 2 (LNO) as a prelithiation additive faces critical challenges including poor rate capability (≤0.1 C), limited capacity, and gas evolution during cycling. Here, we report a metal-dopant lattice engineering strategy that simultaneously addresses these challenges through three synergistic mechanisms: (i) particle size reduction from 30 μm to 500 nm, shortening Li + diffusion pathways; (ii) b-axis lattice expansion (Δb/b ≈ 0.29%) and bandgap narrowing (from 1.2 eV to 0.6 eV), enhancing both ionic and electronic transport; and (iii) strengthened oxygen anchoring via short Cu–O bonds (1.885 Å), suppressing superoxide-related side reactions. Critically, this synthesis employs a one-step solid-state heat treatment using only conventional furnace equipment, directly compatible with existing production lines. The doped LNO (Li 2 Ni 0.9 Cu 0.1 O 2 , designated as LCNO) delivers an exceptional capacity of 492.1 mAh g⁻ 1 at 0.5 C (vs. 282.0 mAh g⁻ 1 for pristine LNO). When integrated into manufacturing-relevant NCM-811‖Si/C pouch cells activated under fast-formation protocols (2 h), LCNO delivers 87% capacity retention (vs. 80% for pristine LNO) after 250 cycles with suppressed gas evolution. Notably, this scalable doping strategy enables industrial manufacturing, bridging the gap from laboratory innovation to commercial production for high-performance prelithiation additives. Download: Download high-res image (163KB) Download: Download full-size image In this work, we report lattice engineering of Li 2 NiO 2 via metal doping (LCNO and LGNO), as the prelithiation, which enables scalable Li 2 NiO 2 prelithiation additives with fast kinetics, high capacity, and suppressed gas evolution. This scalable doping strategy enables industrial manufacturing, bridging the gap from laboratory innovation to commercial production for high-performance prelithiation additives.