Stabilized lithium metal powder (SLMP) has been applied during battery assembly to effectively prelithiate high capacity (1500-2500 mAh/g) silicon-carbon nanotube (Si-CNT) anodes, eliminating the 20-40% first cycle irreversible capacity loss. Pressure-activation of SLMP is shown to enhance prelithiation and enable capacity matching between Si-CNT anodes and lithium nickel cobalt aluminum oxide (NCA) cathodes in full batteries with minimal added mass. The prelithiation approach enables high energy density NCA/Si-CNT batteries achieving >1000 cycles at 20% depth-of-discharge.

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Often gaining insight into the functioning of biomolecular systems requires to follow their dynamics along a microscopic reaction coordinate ͑RC͒ on a macroscopic time scale, which is beyond the reach of current all atom molecular dynamics ͑MD͒ simulations. A practical approach to this inherently multiscale problem is to model the system as a fictitious overdamped Brownian particle that diffuses along the RC in the presence of an effective potential of mean force ͑PMF͒ due to the rest of the system. By employing the recently proposed FR method ͓I. Kosztin et al., J. Chem. Phys. 124, 064106 ͑2006͔͒, which requires only a small number of fast nonequilibrium MD simulations of the system in both forward and time reversed directions along the RC, we reconstruct the PMF: ͑1͒ of deca-alanine as a function of its end-to-end distance, and ͑2͒ that guides the motion of potassium ions through the gramicidin A channel. In both cases the computed PMFs are found to be in good agreement with previous results obtained by different methods. Our approach appears to be about one order of magnitude faster than the other PMF calculation methods and, in addition, it also provides the positiondependent diffusion coefficient along the RC. Thus, the obtained PMF and diffusion coefficient can be used in an overdamped Brownian model to estimate important characteristics of the studied systems, e.g., the mean folding time of the stretched deca-alanine and the mean diffusion time of the potassium ion through gramicidin A.

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