very high saturation fields, similar to the parent powders. This implies that these submicrometer laminated cores can be used in high-power applications where excitation fields are large.In conclusion, we have successfully fabricated Fe/SiO 2 submicrometer laminates that have lateral dimensions of a few to several hundred micrometers and submicrometer thicknesses. The sheet structure is retained during the consolidation, giving rise to laminated soft Fe cores. High-frequency measurements show that the maximum operating frequency can be increased to about 50 MHz, a more than two orders of magnitude improvement over the parent commercial powders. We ascribe these observations to the combination of submicrometer-scale lamination and the silica coating which effectively prevents eddy-current power loss at high frequencies.

Unlocking the full potential of rechargeable magnesium batteries has been partially hindered by the reliance on chloride-based complex systems. Despite the high anodic stability of these electrolytes, they are corrosive toward metallic battery components, which reduce their practical electrochemical window. Following on our new design concept involving boron cluster anions, monocarborane CB11H12(-) produced the first halogen-free, simple-type Mg salt that is compatible with Mg metal and displays an oxidative stability surpassing that of ether solvents. Owing to its inertness and non-corrosive nature, the Mg(CB11H12)2/tetraglyme (MMC/G4) electrolyte system permits standardized methods of high-voltage cathode testing that uses a typical coin cell. This achievement is a turning point in the research and development of Mg electrolytes that has deep implications on realizing practical rechargeable Mg batteries.

No abstract

Summary “...each metal has a certain power, which is different from metal to metal, of setting the electric fluid in motion...” Count Alessandro Volta. Inspired by the first rechargeable magnesium battery prototype at the dawn of the 21st century, several research groups have embarked on a quest to realize its full potential. Despite the technical accomplishments made thus far, challenges, on the material level, hamper the realization of a practical rechargeable magnesium battery. These are marked by the absence of practical cathodes, appropriate electrolytes and extremely sluggish reaction kinetics. Over the past few years, an increased interest in this technology has resulted in new promising materials and innovative approaches aiming to overcome the existing hurdles. Nonetheless, the current challenges call for further dedicated research efforts encompassing fundamental understanding of the core components and how they interact with each other to offering new innovative solutions. In this review, we seek to highlight the most recent developments made and offer our perspectives on how to overcome some of the remaining challenges.

A high energy-density Sn anode capable of displaying superior operating voltages and capacity, for rechargeable Mg-ion batteries, is highlighted. The intended application and performance of the anode is confirmed by coupling it with a Mo(6)S(8) cathode in a conventional battery electrolyte.

No abstract

No abstract

Here we report the study of Li and Li oxides insertion in αMnO 2 with firstprinciples density functional theory calculations. For Li insertion, the redox reaction is characterized with a particular order of the reduction of Mn ions. It induces asymmetric changes of lattice parameters through Jahn−Teller distortion of MnO 6 units. At composition of LiMn 2 O 4 , the ratio between lattice parameter a and b extends to the highest value, 1.19. The severe structural deformation is concluded to be the major cause of the irreversible capacity when αMnO 2 is used as Li-ion battery cathodes. On the other hand, the structure of αMnO 2 is stable to reversibly insert and remove Li oxides. Li oxides inserted αMnO 2 is half metallic instead of insulating. On the basis of our results, a mechanism is proposed to explain the role of αMnO 2 in the catalyzed decomposition of Li 2 O 2 . The key step in this mechanism is the insertion of Li oxides in αMnO 2 . The insertion transfers electrons from Li oxides to MnO 2 and partially oxidized Li oxides, making the subsequent release of O 2 easier.