Realizing High Capacity and Zero Strain in Layered Oxide Cathodes via Lithium Dual-Site Substitution for Sodium-Ion Batteries.

Sodium-ion batteries have garnered unprecedented attention as an electrochemical energy storage technology, but it remains challenging to design high-energy-density cathode materials with low structural strain during the dynamic (de)sodiation processes. Herein, we report a P2-layered lithium dual-site-substituted NaLi[MgLiMn]O (NMLMO) cathode material, in which Li ions occupy both transition-metal (TM) and alkali-metal (AM) sites. The combination of theoretical calculations and experimental characterizations reveals that Li creates Na-O-Li electronic configurations to boost the capacity derived from the oxygen anionic redox, while Li serves as LiO prismatic pillars to stabilize the layered structure through suppressing the detrimental phase transitions.

Boosting the Kinetics and Stability of Zn Anodes in Aqueous Electrolytes with Supramolecular Cyclodextrin Additives.

The hydrophobic internal cavity and hydrophilic external surface of cyclodextrins (CDs) render promising electrochemical applications. Here, we report a comparative and mechanistic study on the use of CD molecules (α-, β-, and γ-CD) as electrolyte additives for rechargeable Zn batteries. The addition of α-CD in aqueous ZnSO solution reduces nucleation overpotential and activation energy of Zn plating and suppresses H generation.

Tuning Interphase Chemistry to Stabilize High-Voltage LiCoO Cathode Material via Spinel Coating.

Cathode electrolyte interphases (CEIs) are critical to the cycling stability of high-voltage cathodes for batteries, yet their formation mechanism and properties remain elusive. Here we report that the compositions of CEIs are largely controlled by abundant species in the inner Helmholtz layer (IHL) and can be tuned from material aspects. The IHL of LiCoO (LCO) was found to alter after charging, with a solvent-rich environment that results in fragile organic-rich CEIs.

Building Homogenous Li TiO Coating Layer on Primary Particles to Stabilize Li-Rich Mn-Based Cathode Materials.

Li-rich Mn-based oxides (LRMOs) are promising cathode materials for next-generation lithium-ion batteries (LIBs) with high specific energy (≈900 Wh kg ) because of anionic redox contribution. However, LRMOs suffer from issues such as irreversible release of lattice oxygen, transition metal (TM) dissolution, and parasitic cathode-electrolyte reactions. Herein, a facile, scalable route to build homogenous and ultrathin Li TiO (LTO) coating layer on the primary particles of LRMO through molten salt (LiCl) assisted solid-liquid reaction between TiO and Li Mn Co Ni O is reported.

Stabilizing Zinc Electrodes with a Vanillin Additive in Mild Aqueous Electrolytes.

Metallic zinc (Zn) is an attractive anode material to use for building an aqueous battery but suffers from dendritic growth and water-induced corrosion. Herein, we report the use of vanillin as a bifunctional additive in aqueous electrolyte to stabilize the Zn electrochemistry. Computational, spectroscopic, and electrochemical studies suggest that vanillin molecules preferentially absorb in parallel on the Zn surface to homogenize the Zn plating and favorably coordinate with Zn to weaken the solvation interaction between HO and Zn, resulting in a compact, dendrite-free Zn deposition and a stable electrode-electrolyte interface with suppressed hydrogen evolution and hydroxide sulfate formation.

Electroless Formation of a Fluorinated Li/Na Hybrid Interphase for Robust Lithium Anodes.

Engineering a stable solid electrolyte interphase (SEI) is one of the critical maneuvers in improving the performance of a lithium anode for high-energy-density rechargeable lithium batteries. Herein, we build a fluorinated lithium/sodium hybrid interphase via a facile electroless electrolyte-soaking approach to stabilize the repeated plating/stripping of lithium metal. Jointed experimental and computational characterizations reveal that the fluorinated hybrid SEI mainly consisting of NaF, LiF, LiPOF, and organic components features a mosaic polycrystalline structure with enriched grain boundaries and superior interfacial properties toward Li.

Growing Nanostructured CuO on Copper Foil via Chemical Etching to Upgrade Metallic Lithium Anode.

Metallic lithium is one of the most promising anode materials to build next generation electrochemical power sources such as Li-air, Li-sulfur, and solid-state lithium batteries. The implementation of rechargeable Li-based batteries is plagued by issues including dendrites, pulverization, and an unstable solid electrolyte interface (SEI). Herein, we report the use of nanostructured CuO grown on commercial copper foil (CuO@Cu) via chemical etching as a Li-reservoir substrate to stabilize SEI formation and Li stripping/plating.