MXene Nanofibers Confining MnOx Nanoparticles: A Flexible Anode for High-Speed Lithium Ion Storage Networks

The electron and ion conductivities of anode materials such as MnOx affect critically the properties of anodes in Li-ion batteries. Herein, a three-dimensional (3D) nanofibers network (MnOx-MXene/CNFs) for high-speed electron...

Fast Fluoride Ion Conduction in Molecular Cation-Containing Compounds, NH4(Mg1-xLix)F3-x and (NH4)2(Mg1-xLix)F4-x

Aiming development of the fast anion conductors, we proposed a new material design using flexible molecular cation as a host cation, and demonstrated it with fluoride ion conduction in NH4(Mg1-xLix)F3-x and (NH4)2(Mg1-xLix)F4-x. Relatively high fluoride ion conductivities of 4.8×10-5 S cm-1 and 8.4×10-6 S cm-1 were achieved at 323 K in (NH4)2(Mg0.85Li0.15)F3.85 and NH4(Mg0.9Li0.1)F2.9, respectively. Our findings suggest molecular cation-containing compounds can be attractive material groups for fast anion conductors.

Synthesis and Triple Conductive Properties of Ba and Fe Co-Doped Sr2TiO4 Based Layered Perovskite: (BaxSr2-x) (Ti0.9Fe0.1)O4-δ (X= 0.05, 0.10)

This study investigated the effects of Ba substitution on protonic conductive properties in the Fe doped Sr2TiO4 layered perovskite. We synthesized sintered samples of (BaxSr2-x)(Ti0.90Fe0.10)O4-δ (x= 0.05, 0.10) (BSTF05, BSTF10). The result of X-ray diffraction suggests that solid solute limitation of Ba is between x= 0.05 and 0.10. BSTF05 at 600 °C shows proton and oxide-ion conductivities as well as elecronic conductivity. It means that BSTF05 is a triple conductor at 600 °C under oxidation atmosphere. The proton conductivities in BSTF05 are lower than that in Ba un-doped Sr2(Ti0.9Fe0.1)O4-δ evaluated in our previous work, suggesting that the effect of the Ba substitution on proton defect generation is small. The redox reaction of Fe ions is more important for creation of proton defects in the layered perovskites.

Synthesis and Characterization of LiFe1-xGdxPO4/C (x = 0.01; 0.05; 0.07) for a Lithium Battery Cathode

Synthesis of LiFe1-xGdxPO4/C with (x = 0.01; 0.05; 0.07) have been carried out using a solid-state method from LiH2PO4, Fe2O3, Gd2O3, and Carbon. Al reactant are mixed and mashed with a ball milling for 8 hours, then heated at 80°C for 2 hours to evaporate free water. To complete the reaction, the sample then was sintered at two different temperature; first at 350°C for 6 hours and continue at 830°C for 10 hours under Argon gas (Ar) atmosphere. The sintered powder was characterized by XRD to determine the structure and phase purity. Sample LiFe1-xGdxPO4/C (x = 0.01; 0.05; 0.07) was adopted orthorhombic crystal structure and pnma space group, and no impurities detected. In general, the lattice parameter decreases with increasing Fe concentration, because of the size of the Fe3+ ion is smaller than that Gd3+ ion. Conductivities of LiFe0.93xGd0.07PO4/C, LiFe0.95Gd0.05PO4/C and LiFe0.99Gd0.01PO4/C are 2.17 x 10-4 S/cm, 1.54 x 10-4 S/cm, and 2.02 x 10-4 S/cm, respectively.

A series of M3PS4 (M = Ag, Cu and Ag/Cu) thiophosphates with diamond-like structures exhibiting large second harmonic generation responses and moderate ion conductivities

Diamond-like thiophosphates exhibiting large second harmonic generation responses and moderate ion conductivities were systematically studied.

Tetramethylurea dimer/lithium salt-based deep eutectics as a novel class of eutectic electrolytes

Graphical abstract of our work including structures of tetramethylurea (TMU) dimer and Li salts, and photographs and ion-conductivities of the resulting deep eutectic electrolytes.

The precise synthesis of twin-born Fe3O4/FeS/carbon nanosheets for high-rate lithium-ion batteries

Metal oxides/sulfides have been considered as promising anode candidates for use in next-generation lithium-ion batteries (LIBs), but the large volume changes and poor electron and ion conductivities limit their practical applications.

Ionic Conduction Through Reaction Products at the Electrolyte/electrode Interface in All-Solid-State Li⁺ Batteries

The development of all-solid-state lithium ion batteries has been hindered by the formation of a poorly conductive interphase at the interface between electrode and electrolyte materials. In the manuscript, we shed light on this problem by computationally evaluating potential lithium ion diffusion pathways through metastable arrangements of product phases that can form at 56 interfaces between common electrode and electrolyte materials. The evaluation of lithium-ion conductivities in the product phases is made possible by the use of machine-learned interatomic potentials trained on the fly. We identify likely reasons for the degradation of solid-state battery performance and discuss how these problems could be mitigated. These results provide enhanced understanding of how interface impedance growth limits the performance of all-solid-state lithium-ion batteries.

Ionic Conduction Through Reaction Products at the Electrolyte/electrode Interface in All-Solid-State Li⁺ Batteries

The development of all-solid-state lithium ion batteries has been hindered by the formation of a poorly conductive interphase at the interface between electrode and electrolyte materials. In the manuscript, we shed light on this problem by computationally evaluating potential lithium ion diffusion pathways through metastable arrangements of product phases that can form at 56 interfaces between common electrode and electrolyte materials. The evaluation of lithium-ion conductivities in the product phases is made possible by the use of machine-learned interatomic potentials trained on the fly. We identify likely reasons for the degradation of solid-state battery performance and discuss how these problems could be mitigated. These results provide enhanced understanding of how interface impedance growth limits the performance of all-solid-state lithium-ion batteries.