Lithium oxide (Li 2 O) is activated in the presence of a layered composite cathode material (HEM) significantly increasing the energy density of lithium-ion batteries. The degree of activation depends on the current rate, electrolyte salt, and anode type. In full-cell tests, the Li 2 O was used as a lithium source to counter the first-cycle irreversibility of high-capacity composite alloy anodes. When Li 2 O is mixed with HEM to serve as a cathode, the electrochemical performance was improved in a full cell having an SiO-SnCoC composite as an anode. The mechanism behind the Li 2 O activation could also explain the first charge plateau and the abnormal high capacity associated with these high energy cathode materials.

Synthetic, Structural, and Electrochemical Study of Monoclinic Na 4Ti5O12 as a Sodium-Ion Battery Anode Material. -The monoclinic phase of Na 4Ti5O12 is obtained by loss of Na under atmospheric conditions from Na 4.6Ti5O12 which itself is prepared by solid state reaction of TiO2 and Na16Ti10O26 in a molar ratio providing a 10% excess of Na (dry H 2 gas; 900 C, 1 h). Na16Ti10O26 is obtained by calcination of stoichiometric amounts of TiO 2 and Na2CO3 (1. 700 C, 13 h, 2. 850 C, 13 h). Monoclinic Na 4Ti5O12 consists of continuous channels with partially occupied Na sites, providing space for the intercalation of excess Na (space group C2/m, powder and synchrotron XRD). Electrochemical Na intercalation/deintercalation shows a comparable or higher reversible capacity than for trigonal Na4Ti5O12. Neutron powder diffraction reveals the preferred sites and occupancies of the excess Na. In situ synchrotron XRD under electrochemical cycling reveals the crystal lattice undergoes strongly anisotropic volume changes during cycling. -(NAEYAERT, P. J. P.; AVDEEV, M.; SHARMA, N.; YAHIA, H. B.; LING*, C. D.; Chem. Mater. 26 (2014) 24, 7067-7072,

The title compounds were synthesized by a hydrothermal route from a 1:1 molar ratio of lithium fluoride and transition-metal acetate in an excess of water. The crystal structures were determined using a combination of powder and/or single-crystal X-ray and neutron powder diffraction (NPD) measurements. The magnetic structure and properties of Co(OH)F were characterized by magnetic susceptibility and low-temperature NPD measurements. M(OH)F (M = Fe and Co) crystallizes with structures related to diaspore-type α-AlOOH, with the Pnma space group, Z = 4, a = 10.471(3) Å, b = 3.2059(10) Å, and c = 4.6977(14) Å and a = 10.2753(3) Å, b = 3.11813(7) Å, and c = 4.68437(14) Å for the iron and cobalt phases, respectively. The structures consist of double chains of edge-sharing M(F,O)6 octahedra running along the b axis. These infinite chains share corners and give rise to channels. The protons are located in the channels and form O-H···F bent hydrogen bonds. The magnetic susceptibility indicates an antiferromagnetic ordering at ∼40 K, and the NPD measurements at 3 K show that the ferromagnetic rutile-type chains with spins parallel to the short b axis are antiferromagnetically coupled to each other, similarly to the magnetic structure of goethite α-FeOOH.

No abstract