Materials that can perform simultaneous functions allow for reductions in the total system mass and volume. Developing technologies to produce flexible batteries with good performance in combination with high specific strength is strongly desired for weight- and power-sensitive applications such as unmanned or aerospace vehicles, high-performance ground vehicles, robotics, and smart textiles. State of the art battery electrode fabrication techniques are not conducive to the development of multifunctional materials due to their inherently low strength and conductivities. Here, we present a scalable method utilizing carbon nanotube (CNT) nonwoven fabric-based technology to develop flexible, electrochemically stable (∼494 mAh·g(-1) for 150 cycles) battery anodes that can be produced on an industrial scale and demonstrate specific strength higher than that of titanium, copper, and even a structural steel. Similar methods can be utilized for the formation of various cathode and anode composites with tunable strength and energy and power densities.

The optical absorption spectra of the first excited singlet states of the benzene, toluene, and toluene–benzene dimers, created in a supersonic molecular jet, are reported. The absorption spectra are detected through two-color time of flight mass spectroscopy; this method eliminates fragmentation of dimers and higher clusters and the dimer spectra are uniquely observed. The benzene dimer observed in this experiment is suggested to have a parallel stacked and displaced configuration of C2h symmetry. Both the toluene and toluene–benzene dimers have two configurations: parallel stacked and displaced [based on (benzene)2] and perpendicular. (Benzene)2, (toluene)2, and toluene–benzene form excimers in the excited state for the parallel stacked displaced configurations. The transformation of (benzene)2 to the excimer takes place at the 00 with a ∼0 cm−1 barrier while the excimer is formed for toluene–benzene with a ∼900 cm−1 barrier. An exciton analysis of the (benzene)2 000 and 610 yields M12, the excitation exchange interaction, equal to ∼1.6 cm−1.

Transition metal fluorides (MFx ) offer remarkably high theoretical energy density. However, the low cycling stability, low electrical and ionic conductivity of metal fluorides have severely limited their applications as conversion-type cathode materials for lithium ion batteries. Here, a scalable and low-cost strategy is reported on the fabrication of multifunctional cobalt fluoride/carbon nanotube nonwoven fabric nanocomposite, which demonstrates a combination of high capacity (near-theoretical, 550mAhgCoF2-1) and excellent mechanical properties. Its strength and modulus of toughness exceed that of many aluminum alloys, cast iron, and other structural materials, fulfilling the use of MFx -based materials in batteries with load-bearing capabilities. In the course of this study, cathode dissolution in conventional electrolytes has been discovered as the main reason that leads to the rapid growth of the solid electrolyte interphase layer and attributes to rapid cell degradation. And such largely overlooked degradation mechanism is overcome by utilizing electrolyte comprising a fluorinated solvent, which forms a protective ionically conductive layer on the cathode and anode surfaces. With this approach, 93% capacity retention is achieved after 200 cycles at the current density of 100 mA g(-1) and over 50% after 10 000 cycles at the current density of 1000 mA g(-1) .

: :86 2 1 9 00 5 SECURITY CLASSIFICATION OF THIS PAGE (Wen SCHEDULE DISTRIBUTION STATEMENT (of this Report)This document has been approved for public release and sale; its ,.distribution is unlimited. ..'Two color time of flight mass spectroscopy studies of benzene solvated by methane, ethane, and propane in a molecular jet _ha' been carried out. Absorption ha. been characterized for'both the 0 and 61transitions of benzene (alkane)x(X=1,2,3...). Atom-atom exponential-6 potentials have been employed to calculate cluster geometry and binding energy. Comparisons between calculations and experiments allow the identification of specific configurations for the " cluster spectroscopic transitions. Cluster spectral shifts can also be identified and a correlation between the size of the cluster red shift and geometry .

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