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Organic polymers have been considered reliable candidates for lithium storage due to their high capacity and lack of volume expansion. Compared with other organic polymers, polyimide has become a very promising electrode material for lithium‐ion batteries (LIBs) because of its easy synthesis, customizable structure and structural stability. A large number of studies have confirmed that the benzene ring structure of polyimide has strong lithium storage capacity as an anode material. Hence, we designed and synthesized polyimide organic polymer (PBPAQ) for the first time. The unique spherical flower structure of this material enhances the interaction between the electrode material and the electrolyte by increasing the contact area. The PBPAQ anode has a specific discharge capacity of 738 mAh g−1 after 100 cycles at 0.1 A g−1. The excellent lithium storage performance of this material laid a foundation for the research of the anode of LIBs in the future. [ABSTRACT FROM AUTHOR]

Binders play a critical role in rechargeable lithium‐ion batteries (LIBs) by holding granular electrode materials, conductive carbons, and current collectors firmly together to form and maintain a continuous electron conduction phase with sufficient mechanical strength. In the commercial LIBs, the dominant binder is polyvinylidene fluoride for the cathode (LiCoO2, LiFePO4, LiNixCotyMnzO2, etc.) and carboxyl methylcellulose/styrene‐butadiene rubber for the anode (graphite and Li4Ti5O12). However, these polymer binders have several drawbacks, particularly, a lack of electronic and lithium‐ion conductivities. Here, a novel organic/inorganic hybrid conductive binder (LAP‐rGO) for both the anode and cathode of LIBs is reported. The binder consists of 2D reduced graphene oxide sheets with anchored long alkane chains. Electrodes prepared using this binder exhibit sufficient high bond strength, fast electrolyte diffusion, high rate charge/discharge performance, and excellent cycling stability. Around 130 mAh g−1 capacity enhancement at 5C is demonstrated for LiFePO4 and Li4Ti5O12 electrodes owing to the combined improvement in electron and lithium ion transportation. LAP‐rGO bond graphite anode shows specific capacity beyond its theoretical value. Electrode slurries prepared using this new binder have superior processing and coating properties that can be prepared under a high humidity and dried using less energy. [ABSTRACT FROM AUTHOR]

Molybdenum trioxide (MoO3) has recently aroused intensive interest as a renowned conversion‐type anode of Li‐ion batteries (LIBs). Nevertheless, the inferior rate capability, sluggish reaction kinetics, and fast capacity decay during a long‐term charge/discharge process seriously inhibits large‐scale commercial application. Herein, abundant oxygen vacancies and MXene nanosheets are elaborately introduced into MoO3 nanobelts through hydrazine reduction and electrostatic assembly to accelerate the ionic and electronic diffusion/transport kinetics for LIBs. Benefitting from the accelerated ion diffusion kinetics, enhanced electrical conductivity, and additional active sites induced by oxygen vacancies as well as the robust interfacial contact, the prepared MoO3−x/MXene heterostructure exhibits excellent lithium‐ion storage performances. First‐principles calculations indicate that the adsorption of Li+ ion and the electrical conductivity are significantly enhanced for the MoO3−x/MXene heterostructure. Thus, the composite exhibits high reversible capacity of 1258 mAh g−1 at 0.1 A g−1 for Li‐ion storage and retains 474 mAh g−1 at 10 A g−1, remarkably higher than those of the previously reported MoO3‐based anode materials. More importantly, the composite is fabricated with commercial LiFePO4 into a full LIB, which displays an unparalleled energy density of 330 Wh kg−1. [ABSTRACT FROM AUTHOR]

A fast one‐step arc discharge exfoliation method is employed to synthesize Si/graphene composites by using a graphite rod filled with a mixture of Si powder and urea as a cathode. During the arc discharge process, the use of urea allows both the introduction of nitrogen atoms into the graphene and the uniform sealing of Si nanoparticles between the thin graphene sheets to occur simultaneously. The resulting N‐doped graphene nanosheets embedded with Si (Si@NG) can act as an electrode material for lithium‐ion batteries and delivers the reversible capacity of 1030 mAh g−1 with a current density of 200 mA g−1 over 100 cycles along with an outstanding coulombic efficiency of 96.84 %. The remarkable electrochemical rate capability performance can be owed to the multiple role of NG, which not only serves as a three‐dimensional conductive support, but also effectively limits the volume variation of Si nanoparticles. The approach proposed here is expected to be extended to the preparation of other alloy anode/graphene hybrids for lithium ion batteries. [ABSTRACT FROM AUTHOR]

Porous FeVO4 is prepared by hydrothermal method and further modified by coating with carbon to obtain FeVO4/C with a hierarchical pore structure. FeVO4/C is used as an anodic electrode in aqueous rechargeable magnesium-ion batteries. The FeVO4/C material not only has improved electrical conductivity as a result of the carbon coating layer, but also has an increased specific surface area as a result of the hierarchical pore structure, which is beneficial for magnesium-ion insertion/deinsertion. Therefore, an aqueous rechargeable magnesium-ion full battery is successfully constructed with FeVO4/C as the anode, Mg-OMS-1 (OMS=octahedral molecular sieves) as the cathode, and 1.0 mol L−1 MgSO4 as the electrolyte. The discharge capacity of the Mg-OMS-1//FeVO4/C aqueous battery is 58.9 mAh g−1 at a current density of 100 mA g−1; this value is obtained by calculating the total mass of two electrodes and the capacity retention rate of this device is 97.7 % after 100 cycles, with almost 100 % coulombic efficiency, which indicates that the system has a good electrochemical reversibility. Additionally, this system can achieve a high energy density of 70.4 Wh kg−1, which provides powerful evidence that an aqueous magnesium-ion battery is possible. [ABSTRACT FROM AUTHOR]

To bridge the gap of the alkali-metal-ion (Li or Na) batteries and supercapacitors, hybrid devices called capacitor batteries are being designed, which are adaptive for large-scale energy-storage systems. Two-dimensional transition-metal carbide materials (MXene) with high electronic conductivities have become capable electrode materials for supercapacitors. Herein, Ti3C2Tx synthesized by selectively etching the Al layer from the Ti3AlC2 presents a remarkable electrochemical performance as an electrode material for the supercapacitor with Li2SO4 or Na2SO4 aqueous electrolyte. It displays a capacitance of 243 F g−1 at a low current density of 100 mA g−1 with a capacitance retention of 95 % in the Li2SO4 electrolyte, and a capacitance of 150 F g−1 at a low current density of 200 mA g−1 with a capacitance retention of 95 % in the Na2SO4 electrolyte, which shows its potential application for capacitor batteries. Moreover, the LiMn2O4//Ti3C2Tx Li-ion capacitor battery and MnO2//Ti3C2Tx Na-ion capacitor battery are designed and assembled for the first time. Such rechargeable aqueous capacitor batteries display capable capacities, remarkable rate abilities, and excellent cycling performances, which further demonstrates that Ti3C2Tx is an outstanding capacitor-type electrode material for capacitor batteries. [ABSTRACT FROM AUTHOR]