Understanding the Beneficial Role of Transition-Metal Layer Na Substitution on the Structure and Electrochemical Properties of the P2-Layered Cathode Na NiTeO.

Layered Na MO sodium oxide positive electrode materials have experienced renewed interest owing to the current commercial attention on sodium-ion batteries. Although there are many attractive qualities of these materials, they suffer from serious shortcomings owing to Na ordering and transition-metal layer gliding that cause a plethora of voltage plateaus during cycling. The P2-layered Na NiTeO (0 ≤ ≤ 0.

Exotic Magnetism in Perovskite KOsO_{3}.

A new perovskite KOsO_{3} has been stabilized under high-pressure and high-temperature conditions. It is cubic at 500 K (Pm-3m) and undergoes subsequent phase transitions to tetragonal at 320 K (P4/mmm) and rhombohedral (R-3m) at 230 K as shown from refining synchrotron x-ray powder diffraction (SXRD) data. The larger orbital overlap integral and the extended wave function of 5d electrons in the perovskite KOsO_{3} allow to explore physics from the regime where Mott and Hund's rule couplings dominate to the state where the multiple interactions are on equal footing.

Interphase Stabilization of LiNi Mn O Cathode for 5 V-Class All-Solid-State Batteries.

Employing high voltage cobalt-free spinel LiNi Mn O (LNMO) as a cathode is promising for high energy density and cost-effectiveness, but it has challenges in all-solid-state batteries (ASSBs). Here, it is revealed that the limitation of lithium argyrodite sulfide solid electrolyte (Li PS Cl) with the LNMO cathode is due to the intrinsic chemical incompatibility and poor oxidative stability. Through a careful analysis of the interphase of LNMO, it is elucidated that even the halide solid electrolyte (Li InCl ) with high oxidative stability can be decomposed to form resistive interphase layers with LNMO in ASSBs.

Development of an Electrophoretic Deposition Method for the In Situ Fabrication of Ultra-Thin Composite-Polymer Electrolytes for Solid-State Lithium-Metal Batteries.

All-solid-state lithium-metal batteries offer higher energy density and safety than lithium-ion batteries, but their practical applications have been pushed back by the sluggish Li transport, unstable electrolyte/electrode interface, and/or difficult processing of their solid-state electrolytes. Li -conducting composite polymer electrolytes (CPEs) consisting of sub-micron particles of an oxide solid-state electrolyte (OSSE) dispersed in a solid, flexible polymer electrolyte (SPE) have shown promises to alleviate the low Li conductivity of SPE, and the high rigidity and large interfacial impedance of OSSEs. Solution casting has been by far the most widely used procedure for the preparation of CPEs in research laboratories; however, this method imposes several drawbacks including particle aggregation and settlement during a long-term solvent evaporation step, excessive use of organic solvents, slow production time, and mechanical issues associated with handling of ultra-thin films of CPEs (<50 µm).

Li S -Integrated PEO-Based Polymer Electrolytes for All-Solid-State Lithium-Metal Batteries.

The integration of Li S within a poly(ethylene oxide) (PEO)-based polymer electrolyte is demonstrated to improve the polymer electrolyte's ionic conductivity because the strong interplay between O and Li from Li S reduces the crystalline volume within the PEO. The Li/electrolyte interface is stabilized by the in situ formation of an ultra-thin Li S/Li S layer via the reaction between Li S and lithium metal, which increases the ionic transport at the interface and suppresses lithium dendrite growth. A symmetric Li/Li cell with the Li S -integrated composite electrolyte has excellent cyclability and a high critical current density of 0.

Rationally Designed PEGDA-LLZTO Composite Electrolyte for Solid-State Lithium Batteries.

A novel composite electrolyte is rationally designed with a polyethylene glycol diacrylate (PEGDA) polymer and a garnet-type fast lithium-ion conductor (LiLaZrTaO, LLZTO) for solid-state lithium batteries. The LLZTO ceramic phase is incorporated into the PEGDA polymeric matrix as nanoparticles. The ionic conductivity of the composite is further optimized with a succinonitrile plasticizer.

Ionic Liquid (IL) Laden Metal-Organic Framework (IL-MOF) Electrolyte for Quasi-Solid-State Sodium Batteries.

An ionic liquid (IL) laden metal-organic framework (MOF) sodium-ion electrolyte has been developed for ambient-temperature quasi-solid-state sodium batteries. The MOF skeleton is designed according to a UIO-66 (Universitetet i Oslo) structure. A sodium sulfonic (-SONa) group grafted to the UIO-based MOF ligand improves the Na-ion conductivity.

Interfacial Chemistry Enables Stable Cycling of All-Solid-State Li Metal Batteries at High Current Densities.

The application of flexible, robust, and low-cost solid polymer electrolytes in next-generation all-solid-state lithium metal batteries has been hindered by the low room-temperature ionic conductivity of these electrolytes and the small critical current density of the batteries. Both issues stem from the low mobility of Li ions in the polymer and the fast lithium dendrite growth at the Li metal/electrolyte interface. Herein, Mg(ClO) is demonstrated to be an effective additive in the poly(ethylene oxide) (PEO)-based composite electrolyte to regulate Li ion transport and manipulate the Li metal/electrolyte interfacial performance.

Elevating Energy Density for Sodium-Ion Batteries through Multielectron Reactions.

It remains a great challenge to explore desirable cathodes for sodium-ion batteries to satisfy the ever-increasing demand for large-scale energy storage systems. In this Letter, we report a NASICON-structured NaMnCr(PO) cathode with high specific capacity and operation potential. The reversible access of the Mn/Mn (3.

Pillar-beam structures prevent layered cathode materials from destructive phase transitions.

Energy storage with high energy density and low cost has been the subject of a decades-long pursuit. Sodium-ion batteries are well expected because they utilize abundant resources. However, the lack of competent cathodes with both large capacities and long cycle lives prevents the commercialization of sodium-ion batteries.

On high-temperature evolution of passivation layer in Li-10 wt % Mg alloy via in situ SEM-EBSD.

Li-10 wt % Mg alloy (Li-10 Mg) is used as an anode material for a solid-state battery with excellent electrochemical performance and no evidence of dendrite formation during cycling. Thermal treatment of Li metal during manufacturing improves the interfacial contact between a Li metal electrode and solid electrolyte to achieve an all solid-state battery with increased performance. To understand the properties of the alloy passivation layer, this paper presents the first direct observation of its evolution at elevated temperatures (up to 325°C) by in situ scanning electron microscopy.

Black phosphorus composites with engineered interfaces for high-rate high-capacity lithium storage.

High-rate lithium (Li) ion batteries that can be charged in minutes and store enough energy for a 350-mile driving range are highly desired for all-electric vehicles. A high charging rate usually leads to sacrifices in capacity and cycling stability. We report use of black phosphorus (BP) as the active anode for high-rate, high-capacity Li storage.

Composition-Tunable Antiperovskite Cu In NNi as Superior Electrocatalysts for the Hydrogen Evolution Reaction.

A group of newly reported antiperovskite nitrides Cu In NNi (0≤x≤1) with tunable composition are employed as electrocatalysts for the hydrogen evolution reaction (HER). Cu In NNi shows the highest intrinsic performance among all developed catalysts with an overpotential of merely 42 mV at 10 mA cm . Stability tests at a high current density of 100 mA cm show its super-stable performance with only 7 mV increase in overpotential after more than 60 hours of measurement, surpassing commercial Pt/C (increase of 170 mV).

In Situ Formation of Liquid Metals via Galvanic Replacement Reaction to Build Dendrite-Free Alkali-Metal-Ion Batteries.

Galvanic replacement reactions have been studied as a versatile route to synthesize nanostructured alloys. However, the galvanic replacement chemistry of alkali metals has rarely been explored. A protective interphase layer will be formed outside templates when the redox potential exceeds the potential windows of nonaqueous solutions, and the complex interfacial chemistry remains elusive.

A Ternary Hybrid-Cation Room-Temperature Liquid Metal Battery and Interfacial Selection Mechanism Study.

The dendrite-free sodium-potassium (Na-K) liquid alloy composed of two alkali metals is one of the ideal alternatives for Li metal as an anode material while maintaining large capacity, low potential, and high abundance. However, Na- or K-ion batteries have limited cathode materials that can deliver stably large capacity. Combining advantages of both, a hybrid-cation liquid metal battery is designed for a Li-ion-insertion-based cathode to deliver stable high capacity using a Na-K liquid anode to avoid dendrites.

Dataset on a primary lithium battery cell with a ferroelectric Li-glass electrolyte and MnO cathode.

Here we show the electrochemical data for a Ferroelectric Electrolyte Battery (FEB) Li/ferroelectric Li-glass electrolyte (LiBaClO) in cellulose/γ-MnO pouch-cell with (2.5 × 2.5 cm) discharged with a green LED load.

General Strategy for Synthesis of Ordered Pt M Intermetallics with Ultrasmall Particle Size.

Controllable synthesis of atomically ordered intermetallic nanoparticles (NPs) is crucial to obtain superior electrocatalytic performance for fuel cell reactions, but still remains arduous. Herein, we demonstrate a novel and general hydrogel-freeze drying strategy for the synthesis of reduced graphene oxide (rGO) supported Pt M (M=Mn, Cr, Fe, Co, etc.) intermetallic NPs (Pt M/rGO-HF) with ultrasmall particle size (about 3 nm) and dramatic monodispersity.

Behavior of Solid Electrolyte in Li-Polymer Battery with NMC Cathode via in-Situ Scanning Electron Microscopy.

We present the first results of in situ scanning electron microscopy (SEM) of an all-solid Li battery with a nickel-manganese-cobalt-oxide (NMC-622) cathode at 50 °C and an operating voltage of 2.7-4.3 V.

Li metal deposition and stripping in a solid-state battery via Coble creep.

Solid-state lithium metal batteries require accommodation of electrochemically generated mechanical stress inside the lithium: this stress can be up to 1 gigapascal for an overpotential of 135 millivolts. Maintaining the mechanical and electrochemical stability of the solid structure despite physical contact with moving corrosive lithium metal is a demanding requirement. Using in situ transmission electron microscopy, we investigated the deposition and stripping of metallic lithium or sodium held within a large number of parallel hollow tubules made of a mixed ionic-electronic conductor (MIEC).

Dataset on a ferroelectric based electrostatic and electrochemical Li-cell with a traditional cathode.

Here we show the electrochemical raw data for a Li/ferroelectric Li-glass electrolyte/plasticizer/Li-rich, F doped LNMO coin cell where the plasticizer is succinonitrile-SN. The nominal composition of the active oxide-host cathode particles is LiNiMnOF (LNMO) that disproportionated into 78 wt% spinel phase LiNiMnOF and 22 wt% Li-rich, F-doped layered phase containing LiMnO planes separated by Li and Ni ions. The LiBaOCl electrolyte was synthesized and ground in ethanol.

Fast Li Conduction Mechanism and Interfacial Chemistry of a NASICON/Polymer Composite Electrolyte.

The unclear Li local environment and Li conduction mechanism in solid polymer electrolytes, especially in a ceramic/polymer composite electrolyte, hinder the design and development of a new composite electrolyte. Moreover, both the low room-temperature Li conductivity and large interfacial resistance with a metallic lithium anode of a polymer membrane limit its application below a relatively high temperature. Here we have identified the Li distribution and Li transport mechanism in a composite polymer electrolyte by investigating a new solid poly(ethylene oxide) (PEO)-based NASICON-LiZr(PO) composite with Li relaxation time and Li → Li trace-exchange NMR measurements.

Enhanced Surface Interactions Enable Fast Li Conduction in Oxide/Polymer Composite Electrolyte.

Li -conducting oxides are considered better ceramic fillers than Li -insulating oxides for improving Li conductivity in composite polymer electrolytes owing to their ability to conduct Li through the ceramic oxide as well as across the oxide/polymer interface. Here we use two Li -insulating oxides (fluorite Gd Ce O and perovskite La Sr Ga Mg O ) with a high concentration of oxygen vacancies to demonstrate two oxide/poly(ethylene oxide) (PEO)-based polymer composite electrolytes, each with a Li conductivity above 10  S cm at 30 °C. Li solid-state NMR results show an increase in Li ions (>10 %) occupying the more mobile A2 environment in the composite electrolytes.

Short O-O separation in layered oxide NaCoO enables an ultrafast oxygen evolution reaction.

The layered oxide NaCoO with Na occupying trigonal prismatic sites between CoO layers exhibits a remarkably high room temperature oxygen evolution reaction (OER) activity in alkaline solution. The high activity is attributed to an unusually short O-O separation that favors formation of peroxide ions by O-O interactions followed by O evolution in preference to the conventional route through surface O-OH species. The dependence of the onset potential on the pH of the alkaline solution was found to be consistent with the loss of H ions from the surface oxygen to provide surface O that may either be attacked by solution OH or react with another O; a short O-O separation favors the latter route.

Antiperovskite Nitrides CuNCoV: Highly Efficient and Durable Electrocatalysts for the Oxygen-Evolution Reaction.

Perovskite oxides have attracted much attention for enabling the oxygen-evolution reaction (OER) over the past decades. Nevertheless, their poor conductivity is still a barrier hindering their use. Herein, we report a catalyst prototype of Co-based antiperovskite nitrides CuNCoV (0 ≤ ≤ 1) to be a highly effective OER electrocatalyst.

Size-, Water-, and Defect-Regulated Potassium Manganese Hexacyanoferrate with Superior Cycling Stability and Rate Capability for Low-Cost Sodium-Ion Batteries.

Potassium manganese hexacyanoferrate (KMHCF) is a low-cost Prussian blue analogue (PBA) having a rigid and open framework that can accommodate large alkali ions. Herein, the synthesis of KMHCF and its application as a high-performance cathode in sodium-ion batteries (NIBs) is reported. High-quality KMHCF with low amounts of crystal water and defects and with homogeneous microstructure is obtained by controlling the nucleation and grain growth by using a high-concentration citrate solution as a precipitation medium.