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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]

The evolution of modern society demands sustainable rechargeable lithium-ion batteries (LIBs) with higher capacity and improved safety standards. High voltage Ni-rich layered transition metal oxides (i.e., LiNi 1-x-y Co x Mn y O 2 , NCM) have emerged as one of the most promising cathode materials in meeting this demand. However, the instability of Ni-rich NCMs cathodes presents challenges in large-scale commercialization. This review examines the energy storage mechanism, e.g., possible (electro)chemical reactions, occurring at the bulk and surface and degradation mechanism of the Ni-rich NCMs cathode materials. To address the challenging instability issue, we highlight recent advances and strategies for bulk and surface engineering of Ni-rich NCMs, including lattice, composition, and microstructure engineering, and electrolyte and materials interfacial engineering. By addressing degradation mechanisms and improving overall stability, this work sheds lights on the potential avenues on the commercialization of Ni-rich cathode-based high-performance LIBs. [Display omitted] • Presenting the historical development and (electro)chemical properties of high-voltage Ni-rich NCM. • Unfolding the degradation mechanism of Ni-rich NCM occurring on bulk and surface. • Proposing modification strategies in bulk and surface chemistry toward stable and high-performance Ni-rich NCM cathode materials. [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]

Solid polymer electrolytes (SPEs) have become increasingly attractive in solid‐state lithium‐ion batteries (SSLIBs) in recent years because of their inherent properties of flexibility, processability, and interfacial compatibility. However, the commercialization of SPEs remains challenging for flexible and high‐energy‐density LIBs. The incorporation of functional additives into SPEs could significantly improve the electrochemical and mechanical properties of SPEs and has created some historical milestones in boosting the development of SPEs. In this study, we review the roles of additives in SPEs, highlighting the working mechanisms and functionalities of the additives. The additives could afford significant advantages in boosting ionic conductivity, increasing ion transference number, improving high‐voltage stability, enhancing mechanical strength, inhibiting lithium dendrite, and reducing flammability. Moreover, the application of functional additives in high‐voltage cathodes, lithium–sulfur batteries, and flexible lithium‐ion batteries is summarized. Finally, future research perspectives are proposed to overcome the unresolved technical hurdles and critical issues in additives of SPEs, such as facile fabrication process, interfacial compatibility, investigation of the working mechanism, and special functionalities. [ABSTRACT FROM AUTHOR]

Searching new organic cathode materials to address the issues of poor cycle stability and low capacity in lithium ion batteries (LIBs) is very important and highly desirable. In this research, a 2D boroxine‐linked chemically‐active pyrene‐4,5,9,10‐tetraone (PTO) covalent organic framework (2D PPTODB COFs) was synthesized as an organic cathode material with remarkable electrochemical properties, including high electrochemical activity (four redox electrons), safe oxidation potential window (between 2.3 and 3.08 V vs. Li/Li+), superb structural/chemical stability, and strong adhesiveness. A binder‐free cathode was obtained by mixing 70 wt % PPTODB and 30 wt % carbon nanotubes (CNTs) as a conductive additive. Promoted by the fast kinetics of electrons/ions, high electrochemical activity, and effective π–π interaction between PPTODB and CNTs, LIBs with the as‐prepared cathode exhibited excellent electrochemical performance: a high specific capacity of 198 mAh g−1, a superb rate ability (the capacity at 1000 mA g−1 can reach 76 % of the corresponding value at 100 mA g−1), and a stable coulombic efficiency (≈99.6 % at the 150th cycle). This work suggests that the concept of binder‐free 2D electroactive materials could be a promising strategy to approach energy storage with high energy density. [ABSTRACT FROM AUTHOR]

A novel conjugated copolymer has been synthesized and employed as an organic cathode material in rechargeable lithium–ion batteries (LIBs). Due to the synergistic effects from conducting aniline and pyrene units, the resultant batteries based on the as‐obtained copolymer can deliver a promising reversible specific capacity of 113 mAh g−1 with a high voltage output of 3.2 V and a remarkable 75.2 % capacity retention after 180 cycles. Moreover, an excellent rate performance is also achieved with a fast recovery of the capacity at different current densities. [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]