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All‐solid‐state lithium‐ion batteries (ASSLIBs) based on sulfide solid‐state electrolytes (S‐SSEs) are considered as one of the most promising choices to address the safety hazards of traditional lithium‐ion batteries. However, the high‐voltage cathodes, such as LiCoO2 (LCO) with high‐valence Co (+3), tend to spontaneously oxidize S‐SSEs, causing polarization increase and rapid degradation. Herein, a self‐sacrificing reductive interphase consisting of CoO/Li2CO3/C, is in situ constructed on LCO surface via a simple carbon‐induced thermal reduction of LCO. With such a design, the Co valence of LCO surface is reduced to +2, reducing the oxidative nature of LCO to avoid reactions with S‐SSEs. As a result, ASSLIBs using Li10GeP2S12 (LGPS) S‐SSEs achieve a high initial capacity of 144.9 mAh g‒1 at 0.2 C and retard 93.1% of initial capacity after 100 cycles. Additionally, excellent rate cyclability of 109.2 mAh g‒1 at 1.0 C with 81.5% retentive capacity for 200 cycles is attained as well. Comprehensive evidence strongly demonstrates the effectiveness of this self‐sacrificing reductive interphase in inhibiting the interfacial reactions and ensuring long‐term cyclability. The proposed concept of a self‐sacrificing reductive interface in this study paves the way for stabilizing the cathode/SSEs interface and offers a novel approach for the design of high‐performance sulfide‐based ASSLIBs. [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]

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]

Electrochemical energy conversion and storage play crucial roles in meeting the increasing demand for renewable, portable, and affordable power supplies for society. The rapid development of nanostructured materials provides an alternative route by virtue of their unique and promising effects emerging at nanoscale. In addition to finding advanced materials, structure design and engineering of electrodes improves the electrochemical performance and the resultant commercial competitivity. Regarding the structural engineering, controlling the geometrical parameters (i.e., size, shape, hetero‐architecture, and spatial arrangement) of nanostructures and thus forming well‐defined nanostructure (WDN) electrodes have been the central aspects of investigations and practical applications. This review discusses the fundamental aspects and concept of WDNs for energy conversion and storage, with a strong emphasis on illuminating the relationship between the structural characteristics and the resultant electrochemical superiorities. Key strategies for actualizing well‐defined features in nanostructures are summarized. Electrocatalysis and photoelectrocatalysis (for energy conversion) as well as metal‐ion batteries and supercapacitors (for energy storage) are selected to illustrate the superiorities of WDNs in electrochemical reactions and charge carrier transportation. Finally, conclusions and perspectives regarding future research, development, and applications of WDNs are discussed. [ABSTRACT FROM AUTHOR]

Stable and seamless interfaces among solid components in all‐solid‐state batteries (ASSBs) are crucial for high ionic conductivity and high rate performance. This can be achieved by the combination of functional inorganic material and flexible polymer solid electrolyte. In this work, a flexible all‐solid‐state composite electrolyte is synthesized based on oxygen‐vacancy‐rich Ca‐doped CeO2 (Ca–CeO2) nanotube, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), and poly(ethylene oxide) (PEO), namely Ca–CeO2/LiTFSI/PEO. Ca–CeO2 nanotubes play a key role in enhancing the ionic conductivity and mechanical strength while the PEO offers flexibility and assures the stable seamless contact between the solid electrolyte and the electrodes in ASSBs. The as‐prepared electrolyte exhibits high ionic conductivity of 1.3 × 10−4 S cm−1 at 60 °C, a high lithium ion transference number of 0.453, and high‐voltage stability. More importantly, various electrochemical characterizations and density functional theory (DFT) calculations reveal that Ca–CeO2 helps dissociate LiTFSI, produce free Li ions, and therefore enhance ionic conductivity. The ASSBs based on the as‐prepared Ca–CeO2/LiTFSI/PEO composite electrolyte deliver high‐rate capability and high‐voltage stability. [ABSTRACT FROM AUTHOR]

The sulfur cathode in traditional lithium-sulfur batteries suffers from poor cyclability due to polysulfide shuttling effect as well as large volume change during charge/discharge processes. Gum arabic (GA), a low cost, nontoxic, and sustainable natural polymer from Acacia senegal, is adopted as a binder for the sulfur cathode to address these issues. The excellent mechanical properties of GA endow the cathode with high binding strength and suitable ductility to buffer volume change, while the functional groups chemically and physically confine sulfur species within the cathode to inhibit the shuttling effect of polysulfides. Additionally, GA shifts the electrode fabrication process from the organic solvent process to an aqueous process, eliminates the use of toxic organic solvents, and achieves uniformly distributed electrode with lower impedance. A remarkable cycling performance, i.e., 841 mAh g−1 at low current rate of C/5, is achieved throughout 500 cycles due to the bifunctions of the GA binder. [ABSTRACT FROM AUTHOR]

Keywords: CuCl redox reaction; dynamic protection mechanisms; Li/Cu alloys; lithium anode protection; lithium dendrites EN CuCl redox reaction dynamic protection mechanisms Li/Cu alloys lithium anode protection lithium dendrites 1 1 1 04/25/22 20220421 NES 220421 B Lithium Anode Protection b In article number 2103480, Chao Lai, Shanqing Zhang and co-workers develop a porous protective layer that consists of a conductive Li-Cu alloy and electrochemically active CuCl on the surface of a lithium anode that evolves with the cycling process and ensures a homogeneous distribution of charge on the lithium anode surface, and subsequently, facilitates the uniform diffusion and deposition of Li SP + sp ions. CuCl2-Modified Lithium Metal Anode via Dynamic Protection Mechanisms for Dendrite-Free Long-Life Charging/Discharge Processes (Adv. CuCl redox reaction, dynamic protection mechanisms, Li/Cu alloys, lithium anode protection, lithium dendrites. [Extracted from the article]

Highlights from the article: Lithium Ion Batteries: A Hollow-Shell Structured V2O5 Electrode-Based Symmetric Full Li-Ion Battery with Highest Capacity (Adv. Keywords: full cell; lithium-ion batteries; multi-hollow-shell; symmetric batteries; V2O5 V2O5, full cell, symmetric batteries, lithium-ion batteries, multi-hollow-shell.

The symmetric batteries with an electrode material possessing dual cathodic and anodic properties are regarded as an ideal battery configuration because of their distinctive advantages over the asymmetric batteries in terms of fabrication process, cost, and safety concerns. However, the development of high‐performance symmetric batteries is highly challenging due to the limited availability of suitable symmetric electrode materials with such properties of highly reversible capacity. Herein, a triple‐hollow‐shell structured V2O5 (THS‐V2O5) symmetric electrode material with a reversible capacity of >400 mAh g−1 between 1.5 and 4.0 V and >600 mAh g−1 between 0.1 and 3.0 V, respectively, when used as the cathode and anode, is reported. The THS‐V2O5 electrodes assembled symmetric full lithium‐ion battery (LIB) exhibits a reversible capacity of ≈290 mAh g−1 between 2 and 4.0 V, the best performed symmetric energy storage systems reported to date. The unique triple‐shell structured electrode makes the symmetric LIB possessing very high initial coulombic efficiency (94.2%), outstanding cycling stability (with 94% capacity retained after 1000 cycles), and excellent rate performance (over 140 mAh g−1 at 1000 mA g−1). The demonstrated approach in this work leaps forward the symmetric LIB performance and paves a way to develop high‐performance symmetric battery electrode materials. [ABSTRACT FROM AUTHOR]

Highlights from the article: Keywords: CO2 reduction reaction; Cu2O nanowires; heterostructures; in situ Raman; intermediates The hybridization of Cu SB 2 sb O/CuO nanowires and Ni nanoparticles improves the adsorption of COOH* intermediates to promote the CO conversion efficiency. CO2 reduction reaction, Cu2O nanowires, heterostructures, in situ Raman, intermediates.

The challenge in the artificial CO2 reduction to fuel is achieving high selective electrocatalysts. Here, a highly selective Cu2O/CuO heterostructure electrocatalyst is developed for CO2 electroreduction. The Cu2O/CuO nanowires modified by Ni nanoparticles exhibit superior catalytic performance with high faradic efficiency (95% for CO). Theoretical and experimental analyses show that the hybridization of Cu2O/CuO nanowires and Ni nanoparticles can not only adjust the d‐band center of electrocatalysts to enhance the intrinsic catalytic activity but also improve the adsorption of COOH* intermediates and suppress the hydrogen evolution reaction to promote the CO conversion efficiency during CO2 reduction reaction. An in situ Raman spectroscopic study further confirms the existence of COOH* species and the engineering intermediates adsorption. This work offers new insights for facile designing of nonprecious transition metal compound heterostructure for CO2 reduction reaction through adjusting the reaction pathway. [ABSTRACT FROM AUTHOR]

The use of electrode additives such as binder and conductive additive (CA) in addition to high pore volume for electrolytes, results in reduced volumetric energy densities of all battery electrodes. In this work, it is proposed to use poly(furfuryl alcohol) (PFA) conductive resin as a trifunctional electrode additive to replace polyvinylidene fluoride (PVDF) and CA while simultaneously enabling low porosity electrode function. The resultant PFA binder has a long‐range ordered structure of conjugated diene, which allow electronic conductivity that leads to a CA‐free electrode fabrication process. The oxygen heteroatoms in the PFA structure reduce the diffusion barriers of lithium ions, lowers the amount of required electrolyte/pore volume and thus, increasing electrode density. Serving as a trifunctional electrode additive, a high electrode density of 2.65 g cm−3 of the LiFePO4 (LFP) electrode and therefore the highest volumetric energy density of 1551 Wh L−1 so far. The LFP electrode using PFA binder can achieve a capacity retention of ≈80% and Coulombic efficiency of over 99.9% after cycling for 500 times. The proposed in situ polymerization strategy could revolutionize the electrode process, with the advantages of being simple, environmentally friendly, and easily scalable to industrial applications. In situ polymerization of simple, low‐cost, and sustainable furfuryl alcohol is integrated into binder design for lithium ion battery electrodes, enabling a high electrode density of 2.65 g cm−3 for the LiFePO4 electrode and therefore the highest volumetric energy density of 1551 Wh L−1. [ABSTRACT FROM AUTHOR]

In article number 1802645, Zhan Lin, Jun Lu and co‐workers propose a universal strategy for interweaving hard and soft polymers to construct 3D network binders to enable high areal capacities with excellent cyclability in lithium‐ion batteries. Elastic modules accommodate the volume variation of Si particles while stiff modules offer mechanically strong electrode frameworks. This strategy can provide a new principle in designing robust binder for high‐energy‐density lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Si anodes suffer an inherent volume expansion problem. The consensus is that hydrogen bonds in these anodes are preferentially constructed between the binder and Si powder for enhanced adhesion and thus can improve cycling performance. There has been little research done in the field of understanding the contribution of the binder's mechanical properties to performance. Herein, a simple but effective strategy is proposed, combining hard/soft polymer systems, to exploit a robust binder with a 3D interpenetrating binding network (3D‐IBN) via an in situ polymerization. The 3D‐IBN structure is constructed by interweaving a hard poly(furfuryl alcohol) as the skeleton with a soft polyvinyl alcohol (PVA) as the filler, buffering the dramatic volume change of the Si anode. The resulting Si anode delivers an areal capacity of >10 mAh cm−2 and enables an energy density of >300 Wh kg−1 in a full lithium‐ion battery (LIB) cell. The component of the interweaving binder can be switched to other polymers, such as replacing PVA by thermoplastic polyurethane and styrene butadiene styrene. Such a strategy is also effective for other high‐capacity electroactive materials, e.g., Fe2O3 and Sn. This finding offers an alternative approach in designing high‐areal‐capacity electrodes through combined hard and soft polymer binders for high‐energy‐density LIBs. A universal strategy, i.e. interweaving hard and soft polymers to construct 3D network binder, is proposed to enable high areal capacities with excellent cyclability in lithium‐ion batteries. Elastic modules accommodate the volume variation of Si particles while stiff modules offer mechanically strong electrode frameworks. This strategy can provide a new principle in designing robust binder for high‐energy‐density lithium‐ion batteries. [ABSTRACT FROM AUTHOR]