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The realization of a stable lithium‐metal free (LiMF) sulfur battery based on amorphous carbon anode and lithium sulfide (Li2S) cathode is here reported. In particular, a biomass waste originating full‐cell combining a carbonized brewer's spent grain (CBSG) biochar anode with a Li2S‐graphene composite cathode (Li2S70Gr30) is proposed. This design is particularly attractive for applying a cost‐effective, high performance, environment friendly, and safe anode material, as an alternative to standard graphite and metallic lithium in emerging battery technologies. The anodic and cathodic materials are characterized in terms of structure, morphology and composition through X‐ray diffraction, scanning and transmission electron microscopy, X‐ray photoelectron and Raman spectroscopies. Furthermore, an electrochemical characterization comprising galvanostatic cycling, rate capability and cyclic voltammetry tests were carried out both in half‐cell and full‐cell configurations. The systematic investigation reveals that unlike graphite, the biochar electrode displays good compatibility with the electrolyte typically employed in sulfur batteries. The CBSG/Li2S70Gr30 full‐cell demonstrates an initial charge and discharge capacities of 726 and 537 mAh g−1, respectively, at 0.05C with a coulombic efficiency of 74%. Moreover, it discloses a reversible capacity of 330 mAh g−1 (0.1C) after over 300 cycles. Based on these achievements, the CBSG/Li2S70Gr30 battery system can be considered as a promising energy storage solution for electric vehicles (EVs), especially when taking into account its easy scalability to an industrial level. [ABSTRACT FROM AUTHOR]

Aluminum (Al) is one of the most promising active materials for producing next-generation negative electrodes for lithium (Li)-ion batteries. It features low density, high specific capacity, and low working potential, making it ideal for producing energy-dense cells. However, this material loses its electrochemical activity within 100 cycles, making it practically unusable. Several claims in the literature support the idea that a dual degradation mechanism is at play. First, the slow diffusion of Li in the Al matrix causes the electrochemical reactions to be partly irreversible, making the initial capacity of the cell drop. Second, the stress caused by cycling make the active material pulverize and lose activity. Recent work shows that shortening the diffusion path of Li by 3D structuring is an effective way to mitigate the first capacity loss mechanism, while alloying Al with other elements effectively mitigates the second one. In this work, we demonstrate that the benefits of 3D structuring and alloying are cumulative and that a mesh made of an Al-magnesium alloy performs better than both a pure Al foil and a foil of an Al-Mg alloy., (© 2024 The Authors. ChemPhysChem published by Wiley-VCH GmbH.)