Highly dispersed primary Li(Ni_1/3Co_1/3Mn_1/3)O₂ crystals, which showed high discharge capacity at a high C-rate, were grown from a Li₂MoO₄ flux.

The surface coating of LiNi_1/3Co_1/3Mn_1/3electrode with 1.1 nm Nb₂O₅nanosheet enhanced the high voltage capability and long term stability of the charged state at 60 °C by reducing the contact area between electrode and electrolyte.

The effects of the partial V-substitution for Ag on the thermoelectric (TE) properties are investigated for a flexible semiconducting compound Ag2S0.55Se0.45. Density functional theory calculations predict that such a partial V-substitution constructively modifies the electronic structure near the bottom of the conduction band to improve the TE performance. The synthesized Ag1.97V0.03S0.55Se0.45 is found to possess a TE dimensionless figure-of-merit (ZT) of 0.71 at 350 K with maintaining its flexible nature. This ZT value is relatively high in comparison with those reported for flexible TE materials below 360 K. The increase in the ZT value is caused by the enhanced absolute value of the Seebeck coefficient with less significant variation in electrical resistivity. The high ZT value with the flexible nature naturally allows us to employ the Ag1.97V0.03S0.55Se0.45 as a component of flexible TE generators.

The composition dependence of the unusual behaviors in electronic and lattice thermal conductivity, κ_ele and κ_lat, in Ag₂S_1-xSe_x (x = 0–0.6 in steps of 0.1, 300 K) is investigated in detail by means of precise electron and heat transport properties measurement, synchrotron X-ray crystal structure and electron density distribution analyses, and sound velocity measurement. We reveal that the κ_ele of Ag₂S_1-xSe_x is strongly affected by the fine electronic structure of the conduction band edge near the chemical potential and the thermoelectric motive force; therefore, these effects make the κ_ele of Ag₂S_1-xSe far different from that calculated by the Wiedemann–Franz law, κ_ele = L₀σT, with the Lorentz number L₀ = π²k_B²/(3e²). It is also clearly demonstrated that the κ_lat of Ag₂S_1-xSe_x is greatly reduced by anharmonic lattice vibrations and that the magnitude of κ_lat is quantitatively reproduced by an equation representing the thermal conductivity under the strongest scattering limit. The κ_lat decreases with increasing x and saturates at 0.4 W m⁻¹ K⁻¹ at x ≥ 0.4. This is caused by the increasing anharmonic lattice vibrations with x, and its saturating behavior is determined by the strongest scattering limit. On the other hand, a negligibly small κ_ele at x = 0 turns out to be non-trivial at x ≥ 0.4 owing to the increasing carrier density with x, most likely contributed by the increasing interstitial Ag defects. Consequently, the total thermal conductivity of Ag₂S_1−xSe_x becomes minimum not at x = 0.5 (composition of the maximum structure entropy) but at x = 0.3.

In this study, we report a large magneto-thermal conductivity effect, potentially usable in heat flow switches and thermoelectric devices, in Ag₂Te over a wide temperature range, including room temperature. When a magnetic field of μ₀H = 9 T is applied to Ag₂Te at 300 K along the direction perpendicular to the heat and electric currents, the thermal conductivity κ decreases by a remarkable 61%. This effect is mainly caused by the suppressed electronic thermal conductivity in association with a significant magnetoresistance effect, but the suppression of the thermal conductivity is larger than that of the electrical conductivity, presumably due to a field-induced decrease in the Lorenz ratio. Its very low lattice thermal conductivity, as low as 0.5 W m⁻¹ K⁻¹, also greatly contributes to the large relative magneto-thermal conductivity effect. The significant decrease in thermal conductivity and the 18% increase in the Seebeck coefficient S lead to a nearly 100% increase in the thermoelectric figure of merit zT = S²σTκ⁻¹ despite the 43% decrease in electrical conductivity σ.