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The lithium-sulfur flow battery (LSFB) is a new addition to the rechargeable lithium flow batteries (LFBs) where sulfur or a sulfur compound is used as the cathode material against the lithium anode. We report here our evaluation of an organic sulfide - dimethyl trisulfide (DMTS), as 1) a catholyte of a LFB and 2) a multi-electron redox mediator for discharging and charging a solid sulfur cathode without any conductive additives. The latter configuration is also known as the redox-targeting lithium-sulfur flow battery (RTLSFB). The LFB provides an initial discharge capacity of 131.5 mAh g −1 DMTS (1.66 A h L −1 ), which decreases to 59 mAh g −1 DMTS (0.75 A h L −1 ) after 40 cycles. The RTLSFB delivers a significantly higher application performance - initial discharge capacity of 1225.3 mAh g −1 sulfur (3.83 A h L −1 ), for which 1030.9 mAh g −1 sulfur (3.23 A h L −1 ) is still available after 40 cycles. The significant increase in the discharge and charge duration of the LFB after sulfur addition indicates that DMTS is better used as a redox mediator in a RTLSFB than as a catholyte in a LFB. [ABSTRACT FROM AUTHOR]

Highlights: Si/C Composite and Nanostructure Engineering: Advanced Si/C composites and multidimensional nanostructures address key challenges in silicon anodes, like volume expansion and unstable SEI, enhancing LIBs performance. Artificial SEI, Prelithiation, and Binders: Focus on stable artificial SEI layers, efficient prelithiation, and cutting-edge binders to improve Coulombic efficiency and reduce capacity loss, enhancing Si anode durability and efficiency. Real-World Application and Scalability: Analysis of these strategies highlights scalability and commercial viability, transitioning Si-anode technologies to practical, high-performance LIBs applications. Silicon (Si) has emerged as a potent anode material for lithium-ion batteries (LIBs), but faces challenges like low electrical conductivity and significant volume changes during lithiation/delithiation, leading to material pulverization and capacity degradation. Recent research on nanostructured Si aims to mitigate volume expansion and enhance electrochemical performance, yet still grapples with issues like pulverization, unstable solid electrolyte interface (SEI) growth, and interparticle resistance. This review delves into innovative strategies for optimizing Si anodes' electrochemical performance via structural engineering, focusing on the synthesis of Si/C composites, engineering multidimensional nanostructures, and applying non-carbonaceous coatings. Forming a stable SEI is vital to prevent electrolyte decomposition and enhance Li+ transport, thereby stabilizing the Si anode interface and boosting cycling Coulombic efficiency. We also examine groundbreaking advancements such as self-healing polymers and advanced prelithiation methods to improve initial Coulombic efficiency and combat capacity loss. Our review uniquely provides a detailed examination of these strategies in real-world applications, moving beyond theoretical discussions. It offers a critical analysis of these approaches in terms of performance enhancement, scalability, and commercial feasibility. In conclusion, this review presents a comprehensive view and a forward-looking perspective on designing robust, high-performance Si-based anodes the next generation of LIBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • A simple and effective interface engineering strategy to construct an artificial protective layer, zinc hyaluronate (denoted as ZH), on the surface of Zn anode is proposed. • The ZH film prevents direct contact between the Zn anode and electrolyte, reducing hydrogen evolution and corrosion, as well as promotes uniform Zn deposition, suppresses dendrite growth. • The symmetric cell assembled with Zn@ZH shows excellent long-term cycling over 3600 h at a current density of 5 mA cm−2 and a capacity density of 5 mAh cm−2. Developing long-cycle stable Zn-ion batteries encounters significant challenges associated with Zn anodes. To address these issues, we propose an interface engineering strategy using an artificial protective layer called zinc hyaluronate (ZH) on the Zn anode surface. The ZH film acts as a barrier, preventing direct contact between Zn anode and electrolyte, reducing hydrogen evolution and corrosion. Its carboxyl and hydroxyl groups create uniform and plentiful nucleophilic sites for Zn2+ ions, promoting uniform Zn deposition and suppressing dendrite growth. Remarkably, a Zn//Zn symmetric cell assembled with ZH-decorated Zn foil (Zn@ZH) exhibits outstanding cycle life, lasting 3600 h at a current density of 5 mA cm−2 and a capacity density of 5 mAh cm−2, much better than cells with pristine Zn anode. Even under extremely tough conditions of 10 mA cm−2 and 10 mAh cm−2, the battery life exceeds 1300 h. Furthermore, the Zn@ZH//V 2 O 5 full cell demonstrates superior capacity retention compared to the Zn//V 2 O 5 cell after 1000 cycles at a current density of 10 A g−1. These results highlight the benefits of the artificial protective layer strategy for advanced Zn anodes, providing insights into the underlying mechanism and promoting the development of high-performance aqueous zinc ion batteries. [ABSTRACT FROM AUTHOR]

A flexible N-doped carbon nanofiber membrane loaded with Nb and Ni nanoparticles (Nb/Ni@NC) was prepared using electrospinning technology and a subsequent thermal annealing method and used as a self-supporting anode material for lithium-ion batteries. The Nb/Ni@NC nanofiber membrane had excellent flexibility and could be folded and bent at will without fragmentation and wrinkling; the nanofibers also had a uniform and controllable morphology with a diameter of 300–400 nm. The electrochemical results showed that the flexible Nb/Ni@NC electrode could deliver a high discharge capacity of 378.7 mAh g−1 after 200 cycles at 0.2 A g−1 and an initial coulombic efficiency of 67.7%, which was higher than that of the pure flexible NC anode in contrast. Moreover, a reversible discharge capacity of 203.6 mAh g−1 after 480 cycles at 1.0 A g−1 was achieved by the flexible Nb/Ni@NC electrode with a capacity decay for each cycle of only 0.075%, which showed an excellent rate capability and cycling stability. [ABSTRACT FROM AUTHOR]

Silicon-based photovoltaic technology is helpful in reducing the cost of power generation; however, it suffers from economic losses and environmental pollution caused by silicon cutting waste. Herein, a hydrothermal method accompanied by heat treatment is proposed to take full advantage of the photovoltaic silicon cutting waste and biomass excrementum bombycis to fabricate flake-like porous Si@C (FP-Si@C) composite anodes for lithium-ion batteries (LIBs). The resulting FP-Si@C composite with a meso-macroporous structure can buffer the severe volume changes and facilitate electrolyte penetration. Meanwhile, the slightly graphitic carbon with high electrical conductivity and mechanical strength tightly surrounds the Si nanoflakes, which not only contributes to the ion/electron transport but also maintains the electrode structural integrity during the repeated lithiation/delithiation process. Accordingly, the synergistic effect of the unique structure of FP-Si@C composite contributes to a high discharge specific capacity of 1322 mAh g−1 at 0.1 A g−1, superior cycle stability with a capacity retention of 70.8% after 100 cycles, and excellent rate performance with a reversible capacity of 406 mAh g−1 at 1.0 A g−1. This work provides an easy and cost-effective approach to achieving the high-value application of photovoltaic silicon cutting waste, as well as obtaining high-performance Si-based anodes for LIBs. [ABSTRACT FROM AUTHOR]

CNO-V 0.005 anode material prepared by simple molten salt method not only has faster lithium-ion diffusion kinetics and lower transfer internal resistance, but also has 276.9 mAh g−1 of high discharge capacity at current density of 2000 mA g−1 over 1000 cycles. [Display omitted] • CoNb 2 O 6 was prepared and was in-situ doped with V5+ ion by a molten-salt method. • The interstitial-doped CNO-V 0.005 exhibits long cycling stability at 2000 mA g−1 (≈ 8C). • The CNO-V 0.005 ||LiFePO 4 full cell has discharge capacity of 150.6 mAh g−1 after 200 cycles. Niobium-based bimetallic oxide, as a potential anode material for fast-charging lithium-ion batteries, has attracted much attention owing to its unique lithium intercalation channel. However, the poor conductivity and structural instability of such material severely limit its further application. In this paper, CoNb 2 O 6 was prepared by a molten-salt method and was in-situ doped with high-valence V5+ ion in different proportions. Different from conventional substitutional doping, a small amount of interstitial doping is more conducive to the entry of V5+ into the gap, which leads to lattice expansion. With the increase of doping amount, elemental Nb5+ was gradually replaced by V5+, which then hinders the Li+ intercalation/de-intercalation to a certain extent. Based on the DFT and electrochemical tests, the interstitial-doped CNO-V 0.005 nanoparticles has not only faster Li+ diffusion kinetics and lower energy barrier, but also delivers high discharge capacity with long cycling stability at high current density of 2000 mA g−1 (≈ 8C). After assembling the full cell with CNO-V 0.005 and commercial LiFePO 4 cathode material, the reversible capacity of 150.6 mAh g−1 could be achieved after 200 cycles at the current density of 1000 mA g−1, demonstrating its application potential in fast- charging lithium-ion batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • A molten salt method for large-scale synthesis of NiNb 2 O 6 submicron particles is proposed. • The NiNb 2 O 6 anode material exhibits an outstanding cycling stability and rate performance up to 20 A g−1 in a Li half-cell. • The assembled NiNb 2 O 6 ||LiFePO 4 full cell can retain 89.3% capacity after 800 cycles at 1.0 A g−1. Niobium-based oxides as lithium-ion battery anode materials have attracted much attention due to their excellent fast-charging capability. However, the solid-phase synthesis of niobates often involves harsh reaction conditions, especially high temperature over 1100 °C. Herein, a molten salt method is proposed to synthesize NiNb 2 O 6 submicron particles, with synthetic temperature of 900 °C, gram-scale production and high reaction yield of 96.6%. Remarkably, NiNb 2 O 6 at the sub-micron scale shows superior electrochemical performance compared to the micron and nano scale sizes, i.e., reversible capacity of 320.9 mAh g−1 after 500 cycles at 2.0 A g−1 (≈8.5C) and high capacity retention of 85.8% over 5000 cycles at 20 A g−1 (≈85C), mainly arising from the pseudo-capacitance electrochemical behavior and stable structure of material during repeated cycles. Moreover, the assembled NiNb 2 O 6 ||LiFePO 4 full cell can retain 89.3% capacity after 800 cycles at 1.0 A g−1. This work offers a simple and efficient method for preparing NiNb 2 O 6 submicron particles as anode material for fast -charging lithium-ion batteries. [ABSTRACT FROM AUTHOR]