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The interfacial instability of high‐nickel layered oxides severely plagues practical application of high‐energy quasi‐solid‐state lithium metal batteries (LMBs). Herein, a uniform and highly oxidation‐resistant polymer layer within inner Helmholtz plane is engineered by in situ polymerizing 1‐vinyl‐3‐ethylimidazolium (VEIM) cations preferentially adsorbed on LiNi0.83Co0.11Mn0.06O2 (NCM83) surface, inducing the formation of anion‐derived cathode electrolyte interphase with fast interfacial kinetics. Meanwhile, the copolymerization of [VEIM][BF4] and vinyl ethylene carbonate (VEC) endows P(VEC‐IL) copolymer with the positively‐charged imidazolium moieties, providing positive electric fields to facilitate Li+ transport and desolvation process. Consequently, the Li||NCM83 cells with a cut‐off voltage up to 4.5 V exhibit excellent reversible capacity of 130 mAh g−1 after 1000 cycles at 25 °C and considerable discharge capacity of 134 mAh g−1 without capacity decay after 100 cycles at −20 °C. This work provides deep understanding on tailoring electric double layer by cation specific adsorption for high‐voltage quasi‐solid‐state LMBs. [ABSTRACT FROM AUTHOR]

Lithium oxalate (Li2C2O4) is an attractive cathode pre-lithiation additive for lithium-ion batteries (LIBs), but its application is hindered by its high decomposition potential (>4.7 V). Due to the liquid–solid synergistic effect of the NaNO2 additive and the LiNi0.83Co0.07Mn0.1O2 (NCM) cathode material, the decomposition efficiency of micro-Li2C2O4 reaches 100% at a low charge cutoff voltage of 4.3 V. Our work boosts the widespread practical application of Li2C2O4 by a simple and promising electrolyte-assisted cathode pre-lithiation strategy. [ABSTRACT FROM AUTHOR]

Li-rich layered oxide (LrLO) cathode has attracted much attention for Li-ion batteries in recent years due to its superior capacity of exceeding 250 mA h g−1. However, these materials still have some inherent drawbacks such as poor rate stability and cycle performance. In this paper, Li-rich cathode material Li1.2Mn0.54Ni0.13Co0.13O2 was modified by silicotungstic acid (HSW) with high electronic and ionic conductivity via a facile approach. The material was characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, and electrochemical tests. The results showed that the thickness of HSW coating was about 5 nm. HSW coating could supply a transfer pathway for Li ions and electrons, resulting in the superior discharge capacity and rate capability. The HSW-LrLO could deliver 158.38 mA h g−1 even at high current density of 500 mA g−1, which was 26.9% higher than that of pristine LrLO. In addition, HSW-LrLO exhibited excellent cycling performance with the capacity retention over 90% at 1 and 5 C. These results were useful to develop effective surface modification for LrLO materials. [ABSTRACT FROM AUTHOR]

The interfacial instability of high-nickel layered oxides severely plagues practical application of high-energy quasi-solid-state lithium metal batteries (LMBs). Herein, a uniform and highly oxidation-resistant polymer layer within inner Helmholtz plane is engineered by in situ polymerizing 1-vinyl-3-ethylimidazolium (VEIM) cations preferentially adsorbed on LiNi 0.83 Co 0.11 Mn 0.06 O 2 (NCM83) surface, inducing the formation of anion-derived cathode electrolyte interphase with fast interfacial kinetics. Meanwhile, the copolymerization of [VEIM][BF 4 ] and vinyl ethylene carbonate (VEC) endows P(VEC-IL) copolymer with the positively-charged imidazolium moieties, providing positive electric fields to facilitate Li + transport and desolvation process. Consequently, the Li||NCM83 cells with a cut-off voltage up to 4.5 V exhibit excellent reversible capacity of 130 mAh g -1 after 1000 cycles at 25 °C and considerable discharge capacity of 134 mAh g -1 without capacity decay after 100 cycles at -20 °C. This work provides deep understanding on tailoring electric double layer by cation specific adsorption for high-voltage quasi-solid-state LMBs., (© 2024 Wiley-VCH GmbH.)

Lithium oxalate (Li 2 C 2 O 4 ) is an attractive cathode pre-lithiation additive for lithium-ion batteries (LIBs), but its application is hindered by its high decomposition potential (>4.7 V). Due to the liquid-solid synergistic effect of the NaNO 2 additive and the LiNi 0.83 Co 0.07 Mn 0.1 O 2 (NCM) cathode material, the decomposition efficiency of micro-Li 2 C 2 O 4 reaches 100% at a low charge cutoff voltage of 4.3 V. Our work boosts the widespread practical application of Li 2 C 2 O 4 by a simple and promising electrolyte-assisted cathode pre-lithiation strategy.