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Metal–Organic Polymers (MOPs) have attracted growing attention for lithium-ion battery (LIB) applications due to their merits in orderly ionic transportation and robust structure stability in electrochemical reactions. However, they suffer from poor electronic conductivity. In this work, we apply first-principles density functional theory to explore the potential of three one-dimensional (1D) electrically conductive C6H2S4TM (TM = Fe, Co, and Ni) MOPs with the π–d conjugated coordination as anode materials for Li+ ions storage. Our theoretical results reveal that these 1D MOPs possess a superior theoretical capacity of over 748 mA h g−1. In particular, the 1D C6H2S4Ni MOP shows an exceptional theoretical specific capacity of 1110 mA h g−1 based on the three-electron transferring reaction, which significantly outperforms the traditional graphite-based anode material in LIBs. Moreover, the resonant charge transfer between Ni metal and ligand within the 1D C6H2S4Ni MOP reduces the diffusion energy barrier of the Li atoms when they migrate on the surface of the MOP. The ultrahigh theoretical specific capacity of the C6H2S4Ni MOP predicts that it can be a promising anode material for LIBs. [ABSTRACT FROM AUTHOR]

Zinc ion batteries (ZIBs) have recently attracted tremendous interest for being low‐cost, environmentally benign, and high energy density. However, the large‐scale practical application of ZIBs is hampered by well‐known undesirable dendrite growth and serious side reactions of the Zn anode during the long‐term cycling process. Herein, a multifunctional water‐glass artificial protection layer with enormous Si─O functional groups is constructed on Zn anode through a simple spin‐coating method. The theoretical and experimental investigation suggests that the as‐constructed interface with rich Si─O hydrophilic functional groups on Zn anode could facilitate the even distribution of electric field distribution and homogeneous wettability, navigate uniform zinc deposition/stripping along the (002) plane, and subsequently lead to well‐suppressed dendrite growth and effective prohibition of oxygen‐involved corrosion. Consequently, the water glass‐modified anode achieves highly reversible Zn plating/stripping over 1500 h at a high current density of 10 mA cm−2 in symmetrical cells, and a high capacity retention ratio of 79.4% at the current density of 5 A g−1 in full cells paired with V2O5 cathode. This proposed water glass coating layer design is cheap, up‐scalable, and facile, which could substantially accelerate the rapid commercialization of zinc anodes and unleash the full potential of renewable ZIBs for next‐generation large‐scale energy storage. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries (LSBs) currently suffer from severe polysulfide shuttling, slow redox kinetics at the sulfur cathode, and irreversible dendrite growth at the lithium anode. To address these issues, a dual interfacial engineering strategy on both the cathode and anode is proposed. For the cathode, iminated polyaniline (iPANI) is used to achieve energetic engineering to induce mid‐energy level to the adsorption of polysulfides, and catalyze the redox conversion of sulfur species, and realize morphological engineering via self‐assembly of iPANI onto a scaffold integrated by reduced graphene oxide (rGO) and carbon nanotubes (CNTs), namely iPANI@rGO‐CNTs. For the anode, the highly conductive and lithiophilic nature and porous nanostructure of the iPANI@rGO‐CNTs composite facilitates the uniform deposition of lithium‐ions, significantly preventing the growth of lithium dendrites. Density functional theory calculations suggest that the iminated functional group at the excited state in iPANI can significantly suppress the shuttling effect, catalyze the conversion of sulfur species, and enhance the conversion of the sulfur species on the sulfur cathode. With the synergic effects of the iPANI@rGO‐CNTs nanoreactors, the as‐prepared LSBs deliver an excellent rate capability and outstanding cycling life. This large‐scale production and application of the iPANI@rGO‐CNTs nanocomposite may lead to the eventual commercialization of LSBs. [ABSTRACT FROM AUTHOR]

Highlights: Cyclohexanedodecol (CHD) could facilitate the Zn dendrite-free plating/stripping at a nanoscale. The CHD molecules could effectively modify the hydrated Zn(H2O)62+ structure in aqueous Zn ion batteries. The addition of CHD could establish robust protection layers on the Zn electrode surface. The CHD-modified electrolytes exhibit long-term cycling stability. Aqueous zinc-ion batteries (AZIBs) can be one of the most promising electrochemical energy storage devices for being non-flammable, low-cost, and sustainable. However, the challenges of AZIBs, including dendrite growth, hydrogen evolution, corrosion, and passivation of zinc anode during charging and discharging processes, must be overcome to achieve high cycling performance and stability in practical applications. In this work, we utilize a dual-functional organic additive cyclohexanedodecol (CHD) to firstly establish [Zn(H2O)5(CHD)]2+ complex ion in an aqueous Zn electrolyte and secondly build a robust protection layer on the Zn surface to overcome these dilemmas. Systematic experiments and theoretical calculations are carried out to interpret the working mechanism of CHD. At a very low concentration of 0.1 mg mL−1 CHD, long-term reversible Zn plating/stripping could be achieved up to 2200 h at 2 mA cm−2, 1000 h at 5 mA cm−2, and 650 h at 10 mA cm−2 at the fixed capacity of 1 mAh cm−2. When matched with V2O5 cathode, the resultant AZIBs full cell with the CHD-modified electrolyte presents a high capacity of 175 mAh g−1 with the capacity retention of 92% after 2000 cycles under 2 A g−1. Such a performance could enable the commercialization of AZIBs for applications in grid energy storage and industrial energy storage. [ABSTRACT FROM AUTHOR]

Lithium metal is considered as an ideal substitute to low‐capacity carbon anodes for rechargeable lithium‐ion batteries (LIBs) given its ultra‐high theoretical specific capacity of 3860 mAh g−1 and the lowest electrochemical potential. However, safety issues stem from the uncontrollable formation and growth of lithium dendrites, which severely plague the practical application of the Li anode. Here, a multi‐functional protection layer, prepared by a one‐step spin‐coating of CuCl2N‐Methyl‐2‐Pyrrolidone (NMP) solution on a lithium metal surface is constructed. The as‐prepared protective layer has a variable porous morphology that consists of a conductive lithium‐copper alloy and electrochemically active CuCl, which proactively facilitates the homogeneous diffusion of Li‐ions, the elimination of random dendrite nuclei, and even distribution of charge at the Li anode surface, and subsequently the uniform deposition of Li+ ions. Under such a dynamic protection mechanism, the proposed CuCl2 modified Li electrode can stably cycle more than 1500 h at a current density of 1 mA cm−2 paired with lithium foil. Moreover, the assembled full battery achieves capacity retention of 85.6% even after 2000 cycles at a high rate of 5 C with a LiFePO4 cathode. This as‐proposed dynamic protection mechanism via the incorporation of the electrochemically active component could provide new guidance in the preparation of the safe and high‐performance lithium metal anodes. [ABSTRACT FROM AUTHOR]

Abstract: Mesoporous Li4Ti5O12 is prepared via ball-milling assisted solid-state reaction with titanyl sulfate and LiOH as precursors. Different from previous reports, the solid-state reaction route generates mesopores in Li4Ti5O12 by removing the impurities after the high-temperature synthesis process. This technique ensures the formation of well-defined mesoporous structure and ultrafine nanoparticles with the size of around 8 nm. The as-prepared sample shows good rate and cycle performance. At the current density of 1750 mA g−1 (10 C), high initial discharge capacity of 174.5 mAh g−1 can be obtained, which can be retained at 143.4 mAh g−1 after 50 cycles. This facile ball-milling assisted solid-state reaction could be a practical way for the mass synthesis of mesoporous Li4Ti5O12 as high-performance anodes. [Copyright &y& Elsevier]