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Solid-state lithium metal batteries require accommodation of electrochemically generated mechanical stress inside the lithium: this stress can be.sup.1,2 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). Here we show that these alkali metals--as single crystals--can grow out of and retract inside the tubules via mainly diffusional Coble creep along the MIEC/metal phase boundary. Unlike solid electrolytes, many MIECs are electrochemically stable in contact with lithium (that is, there is a direct tie-line to metallic lithium on the equilibrium phase diagram), so this Coble creep mechanism can effectively relieve stress, maintain electronic and ionic contacts, eliminate solid-electrolyte interphase debris, and allow the reversible deposition/stripping of lithium across a distance of 10 micrometres for 100 cycles. A centimetre-wide full cell--consisting of approximately 10.sup.10 MIEC cylinders/solid electrolyte/LiFePO.sub.4--shows a high capacity of about 164 milliampere hours per gram of LiFePO.sub.4, and almost no degradation for over 50 cycles, starting with a 1× excess of Li. Modelling shows that the design is insensitive to MIEC material choice with channels about 100 nanometres wide and 10-100 micrometres deep. The behaviour of lithium metal within the MIEC channels suggests that the chemical and mechanical stability issues with the metal-electrolyte interface in solid-state lithium metal batteries can be overcome using this architecture. By containing lithium metal within oriented tubes of a mixed ionic-electronic conductor, a 3D anode for lithium metal batteries is produced that overcomes chemomechanical stability issues at the electrolyte interface., Author(s): Yuming Chen [sup.1] [sup.2] [sup.3] , Ziqiang Wang [sup.1] [sup.2] , Xiaoyan Li [sup.1] [sup.2] [sup.3] [sup.4] , Xiahui Yao [sup.1] [sup.2] , Chao Wang [sup.1] [sup.2] , Yutao [...]

Silicon anodes in lithium batteries expand during discharge, causing failure. This expansion has been used constructively in a material whose architecture controllably and reversibly changes to alter its function. A material that reconfigures when loaded or unloaded with lithium ions., Author(s): Seung-Yeol Jeon, Sung Hoon Kang Author Affiliations: Electrochemical reactions drive morphing of materials If pressure is applied to a block of rubber, it flattens, but reverts to its original [...]

Vanadium pentoxide materials prepared through sol--gel processes act as excellent intercalation hosts for lithium as well as polyvalent cations. A chemometric approach has been applied to study the X-ray absorption near-edge structure (XANES) evolution during in situ scanning of the [Cu.sub.0.1][V.sub.2][O.sub.5] xerogel/Li ions battery. Among the more common techniques, the fixed size windows evolving factor analysis (FSWEFA) permits the number of species involved in the experiment to be determined and the range of existence of each of them. This result, combined with the constraints of the invariance of the total concentration and non-negativity of both concentrations and spectra, enabled us to obtain the spectra of the pure components using a multivariate curve resolution refined by an alternate least squares fitting procedure. This allowed the normalized concentration profile to be understood. This data treatment evidenced the occurrence, for the first time, of three species during the battery charging. This fact finds confirmation by comparison of the pure spectra with the experimental ones. Extended X-ray absorption fine structure (EXAFS) analysis confirms the occurrence of three different chemical environments of Cu during battery charging. 10.1021/ac902865h

Two-step solution-phase reactions are developed for preparing hybrid materials of [Mn.sub.3][O.sub.4] nanoparticles on reduced graphene oxide (RGO) sheets for lithium ion battery applications. The growth-on-graphene approach has offered a new method for designing and preparing battery electrodes based on highly insulating materials.

The article explains the synthesis, characterization, as well as the properties of various ethoxycarbonyl-based organic electrodes used in lithium batteries. Organic components are shown to lead to significant enhancement of the performance of the batteries.

An environmentally friendly approach for the synthesis of orthorhombic [V.sub.2][O.sub.5] single-crystalline nanobelts in the [H.sub.2][O.sub.2] aqueous solution on a large scale is reported. The experimental finding demonstrates that the use of a nanosized belt-like structure could considerably enhance the specific discharge capacity in lithium-ion batteries.