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Abstract: A new advanced Li-ion battery comprising a high performance amorphous columnar silicon thin film anode, a high voltage LiNi0.5Mn1.5O4 spinel composite cathode and fluoroethylene carbonate (FEC)-based electrolyte solution (FEC/DMC 1:4 with 1M LiPF6) is reported. This advanced battery demonstrated hundreds of cycles, excellent charge–discharge efficiency and rate capability. [Copyright &y& Elsevier]

Bariatric surgery (BS) can have negative effects on bone health. Bone microarchitecture quality evaluation using the trabecular bone score (TBS) has not been described in patients after sleeve gastrectomy (SG). To test the hypothesis that the TBS is clinically useful for this population, we evaluated changes in bone mineral density (BMD) and the TBS in a longitudinal cohort study following SG. The measurements before surgery and after 12 and 24 postoperative months were as follows: weight, height, BMI, waist circumference (WC), BMD and TBS. The results at baseline showed the following: a mean BMI of 43 ± 0.56, TBS of 1.25 ± 0.02, lumbar spine BMD T-score of -0.4 ± 0.93, TBS T-score of -2.30 ± 0.21, significantly lower than BMD-T-score, and associated with a BMD-T-TBS-T gap (T-gap) of -2.05 ± 1.26 (-0.24 ± 0.13). One year after surgery, the TBS had significantly improved (+12.12% ± 1.5), leading to a T-gap of -0.296 ± 0.14, which remained stable at 2 years post-surgery. A correlation analysis revealed a significant negative correlation between the T-gap and WC (r = -0.43 p = 0.004). Our interpretation is that abdominal fat may interfere with image acquisition via increased tissue thickness, leading to a false low TBS at baseline. In conclusion, TBS should be interpreted with caution in patients with obesity and elevated WC. Additionally, we show that after SG, the LS microarchitecture measured using the TBS is partially degraded in up to 25% of patients. Further studies are warranted to assess hip bone microarchitecture changes after bariatric surgery.

The development of Li2S electrodes is a crucial step toward industrial manufacturing of Li-S batteries, a promising alternative to Li-ion batteries due to their projected two times higher specific capacity. However, the high voltages needed to activate Li2S electrodes, and the consequent electrolyte solution degradation, represent the main challenge. We present a novel concept that could make feasible the widespread application of Li2S electrodes for Li-S cell assembly. In this concept, the addition of redox mediators as additives to the standard electrolyte solution allows us to recover most of Li2S theoretical capacity in the activation cycle at potentials as low as 2.9 VLi, substantially lower than the typical potentials >4 VLi needed with standard electrolyte solution. Those novel additives permit us to preserve the electrolyte solution from being degraded, allowing us to achieve capacity as high as 500 mAhg(-1)Li2S after 150 cycles with no major structural optimization of the electrodes.

A route for the preparation of binder-free sulfur-carbon cathodes is developed for lithium sulfur batteries. The method is based on the impregnation of elemental sulfur into the micropores of activated carbon fibers. These electrodes demonstrate good electrochemical performance at high current density attributed to the uniform dispersion of sulfur inside the carbon fiber., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We propose herein a new reliable approach to assess solvation numbers of ions confined in carbon nanopores based on dynamic quartz crystal measurements. This was proved for the entire families of alkaline, alkaline-earth cations, and halogen anions. As-assessed hydration numbers appear in the sequence characteristic of a transition from the cosmotropic to a chaotropic-type behavior with the decrease of the ion's charge-to-size ratio. The information on the behavior of ions confined in nanometric space of different (especially charged) carbon materials is in high demand for the development of powerful supercapacitors, nanofiltration membranes, and chemical/biochemical sensors.