Lithium-ion batteries are crucial to the future of energy storage. However, the energy density of current lithium-ion batteries is insufficient for future applications. Sulfur cathodes and silicon anodes have garnered a lot of attention in the field due their high capacity potential. Although recent developments in sulfur and silicon electrodes show exciting results in half cell formats, neither electrode can act as a lithium source when put together into a full cell format. Current methods toward incorporating lithium in sulfur-silicon full cells involves prelithiating silicon or using lithium sulfide. These methods however, complicate material processing and creates safety hazards. Herein, we present a novel full cell battery architecture that bypasses the issues associated with current methods. This battery architecture gradually integrates controlled amounts of pure lithium into the system by allowing lithium the access to external circuit. A high specific energy density of 350 Wh/kg after 250 cycles at C/10 was achieved using this method. This work should pave the way for future researches into sulfur-silicon full cells.

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Water decontamination and oil/water separation are principal motives in the surge to develop novel means for sustainability. In this prospect, supplying clean water for the ecosystems is as important as the recovery of the oil spills since the supplies are scarce. Inspired to design an engineering material which not only serves this purpose, but can also be altered for other applications to preserve natural resources, a facile template-free process is suggested to fabricate a superporous, superhydrophobic ultra-thin graphite sponge. Moreover, the process is designed to be inexpensive and scalable. The fabricated sponge can be used to clean up different types of oil, organic solvents, toxic and corrosive contaminants. This versatile microstructure can retain its functionality even when pulverized. The sponge is applicable for targeted sorption and collection due to its ferromagnetic properties. We hope that such a cost-effective process can be embraced and implemented widely.

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Lithium metal electrodes are regarded as the optimal anode for next generation lithium ion batteries especially in the lithium-sulfur architecture. Unfortunately, the lithium metal anode falls subject to several challenges such as dendrite formation and low Coulombic efficiency, which inhibit its candidacy as a viable technology. As such, substantial research efforts alter cell parameters in effort to manipulate interfacial chemistries, mitigate dendrite growth, and improve cyclability. Unlike conventional efforts, we demonstrate a practical cell operation approach to reinforce the Solid Electrolyte Interphase in lithium anodes via a refined formation protocol governed by the redox reactions found in lithium-sulfur systems. Galvanostatic and electrochemical impedance data on Li-Li symmetrical cells reveal that cell operation during the formation phase plays a critical role on interface stability of lithium metal anodes. Li-Li symmetrical cells subject to our refined protocol, P2, displayed advantages in steadily enduring high cycling currents of 6 mA with minimal polarization, and in lowering the charge transfer resistance at the cell interfaces by a fourfold when compared to cells subject to conventional formation protocols. Additionally, scanning electron microscopy images demonstrate that our formation protocol significantly minimizes the size and dispersion of lithium dendrites, as well as the degree of plated lithium. These effects are enabled by the reinforced SEI formed during P2 which offers a stable ratio between the rates of lithium intercalation to lithium deposition. Microcomputerized tomography characterization further supports these findings by revealing that P2 averts dendrite nucleation sites, and yields greater quantity of SEI species, encompassing 41.1% volume of the entire anode, compared to just 21.5% from the common formation protocol found in literature. Overall, this approach deviates from the convention of materials exploration yet highlights the importance of understanding the nature of interfacial chemistries in response to cell operation. We believe the Daisy Patino and Bo Dong contributed equally to this work.