We show full Li/S cells with the use of balanced and high capacity electrodes to address high power electro-mobile applications. The anode is made of an assembly comprising of silicon nanowires as active material densely and conformally grown on a 3D carbon mesh as a light-weight current collector, offering extremely high areal capacity for reversible Li storage of up to 9 mAh/cm2. The dense growth is guaranteed by a versatile Au precursor developed for homogenous Au layer deposition on 3D substrates. In contrast to metallic Li, the presented system exhibits superior characteristics as an anode in Li/S batteries such as safe operation, long cycle life and easy handling. These anodes are combined with high area density S/C composite cathodes into a Li/S full-cell with an ether- and lithium triflate-based electrolyte for high ionic conductivity. The result is a highly cyclable full-cell with an areal capacity of 2.3 mAh/cm2, a cyclability surpassing 450 cycles and capacity retention of 80% after 150 cycles (capacity loss <0.4% per cycle). A detailed physical and electrochemical investigation of the SiNW Li/S full-cell including in-operando synchrotron X-ray diffraction measurements reveals that the lower degradation is due to a lower self-reduction of polysulfides after continuous charging/discharging.

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Excellent fast-charging performance is a key requirement for lithium-ion batteries intended for automotive applications. Rational particle design for active materials within electrodes represents a strategic approach to minimize kinetic limitationsespecially for the anode, where the lithium intercalation rate affects the overall cell charging capacity at elevated current densities. Typically, for practical applications, natural graphite flakes are shaped into rounded particles via a mechanical spheroidization process. In this work, we show that both surface and bulk particle properties correlate strongly with the applied spheroidization conditions, and directly affect the electrochemical performance, particularly in terms of lithium-intercalation rate. We demonstrate that graphite particles with a surface rich in prismatic planes, structural defects, and oxygen-rich groups are favorable for fast lithium uptake. The influence of the graphite particle characteristics on the lithium intercalation rate plays a key role at the electrode and cell level, affecting the overall cell performance. We provide new insights into particle optimization during spheroidization as an effective strategy for developing fast-charging lithium-ion batteries.

To date, in the textile manufacturing process of warp knitting, trouble-shooting and process optimization mainly rely on empirical knowledge and experiments. This factor limits the achievable increase in productivity and quality. On the other hand, using simulations, different phenomena that affect the quality of the knitted fabric and the knitting process can be clarified in the run-up of the experiments. Consequently, an increase in quality and flexibility can be reached with reduced experimental effort. This paper presents a process simulation of the warp thread dynamics in the thread feeding system of a warp knitting machine. For this purpose, a continuum model of the warp thread that includes the spatial dynamics of the thread and the axial transport movement has been developed.