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All‐solid‐state batteries (ASSBs) with silicon anodes are promising candidates to overcome energy limitations of conventional lithium‐ion batteries. However, silicon undergoes severe volume changes during cycling leading to rapid degradation. In this study, a columnar silicon anode (col‐Si) fabricated by a scalable physical vapor deposition process (PVD) is integrated in all‐solid‐state batteries based on argyrodite‐type electrolyte (Li6PS5Cl, 3 mS cm−1) and Ni‐rich layered oxide cathodes (LiNi0.9Co0.05Mn0.05O2, NCM) with a high specific capacity (210 mAh g−1). The column structure exhibits a 1D breathing mechanism similar to lithium, which preserves the interface toward the electrolyte. Stable cycling is demonstrated for more than 100 cycles with a high coulombic efficiency (CE) of 99.7–99.9% in full cells with industrially relevant areal loadings of 3.5 mAh cm−2, which is the highest value reported so far for ASSB full cells with silicon anodes. Impedance spectroscopy revealed that anode resistance is drastically reduced after first lithiation, which allows high charging currents of 0.9 mA cm−2 at room temperature without the occurrence of dendrites and short circuits. Finally, in‐operando monitoring of pouch cells gave valuable insights into the breathing behavior of the solid‐state cell.

Conductive polymers showing stretchable and transparent properties have received extensive attention due to their enormous potential in flexible electronic devices. Here, we demonstrate a facile and smart strategy for the preparation of structurally stretchable, electrically conductive, and optically semitransparent polyaniline-containing hybrid hydrogel networks as electrode, which show high-performances in supercapacitor application. Remarkably, the stability can extend up to 35,000 cycles at a high current density of 8 A/g, because of the combined structural advantages in terms of flexible polymer chains, highly interconnected pores, and excellent contact between the host and guest functional polymer phase.

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Polysulfide shuttling is a crucial factor in lithium sulfur batteries responsible for capacity fading and degradation. Liquid phase adsorption in combination with nuclear magnetic resonance and X‐ray photoelectron spectroscopy are used to elucidate and quantify polysulfide retention in typical porous cathode materials used in lithium sulfur batteries without cell assembly to achieve a more fundamental understanding of liquid phase adsorption phenomena as a responsible mechanism for polysulfide retention. The individual impact of each pore size increment is quantified on the polysulfide adsorption (PSA). Ultramicropores show eight times higher PSA (1.48 mmol cm−3) than mesopores. Strong heteroatom‐doped ultramicropores show even stronger interactions with polysulfides leading to 25 times higher adsorption compared to hydrophobic mesopores. These findings allow to precisely tailor pore structure and heteroatom distribution of cathode materials for next generation lithium sulfur batteries with prolonged cycle life and reduced capacity fading.