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Considered the promising anode material for next‐generation high‐energy lithium‐ion batteries, SiOx has been slow to commercialize due to its low initial Coulombic efficiency (ICE) and unstable solid electrolyte interface (SEI) layer, which leads to reduced full‐cell energy density, short cycling lives, and poor rate performance. Herein, a novel strategy is proposed to in situ construct an artificial hybrid SEI layer consisting of LiF and Li3Sb on a prelithiated SiOx anode via spontaneous chemical reaction with SbF3. In addition to the increasing ICE (94.5%), the preformed artificial SEI layer with long‐term cycle stability and enhanced Li+ transport capability enables a remarkable improvement in capacity retention and rate capability for modified SiOx. Furthermore, the full cell using Li(Ni0.8Co0.1Mn0.1)O2 and a pre‐treated anode exhibits high ICE (86.0%) and capacity retention (86.6%) after 100 cycles at 0.5 C. This study provides a fresh insight into how to obtain stable interface on a prelithiated SiOx anode for high energy and long lifespan lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

A novel and facile strategy for fabricating red phosphorus@nitrogen doped graphene/carbon nanotube aerogel (P@NGCA) is proposed as a free-standing anode for high energy sodium-ion batteries. Owing to an optimized structure of red P uniformly confined in porous NGCA with high conductivity and mechanical stability, the free-standing P@NGCA anode exhibits outstanding sodium storage performance with a high areal capacity of 3.3 mA h cm−2 and superior initial Coulombic efficiency of 80%. [ABSTRACT FROM AUTHOR]

Understanding the volume expansion behavior of Si anodes and their interaction with electrolyte environments is crucial for developing high-performance lithium-ion batteries (LIBs). This study utilizes a graphene liquid cell for in situ imaging to systematically investigate the volume expansion and etching behavior of Si anode nanoparticles in different electrolyte environments. Comparative experiments on Si@C core-shell nanoparticles assess their volume expansion dynamics. The findings reveal significant variation in the expansion rate of nano Si depending on the electrolyte environment, with chemical etching observed under specific conditions. Conversely, Si@C core-shell structures show mitigated expansion due to the confinement effect of the carbon matrix. Battery performance experiments validate these results, demonstrating the excellent cycling stability of Si@C anodes. Various coating agents are explored to optimize Si@C structures, with dopamine thin layer coating exhibiting the best cycling stability. This study offers fundamental insights into Si anode expansion, electrolyte effects, and carbon coating impacts, advancing LIB technology. [Display omitted] • Graphene liquid cell enables in situ imaging to study volume expansion and etching behavior of Si anode nanoparticles. • Si@C core-shell nanoparticles show reduced Si expansion due to the confinement effect of the carbon matrix. • Polydopamine coating on Si@C structures significantly enhances cycling stability and performance. • Si@PDA anode demonstrated stable capacity of 954 mAh g-1 and excellent rate capability after 500 cycles at 0.2 C. [ABSTRACT FROM AUTHOR]

A novel design strategy for synthesizing hard carbon microspheres (HCMs) from a single source of sodium lignin sulfonate is proposed for a practical anode material of sodium-ion batteries. The HCM has an optimized microstructure, including an enlarged interlayer spacing and few defects, along with a low specific surface area. As an anode material of sodium-ion batteries, HCM is highly promising for practical applications because of its high capacity and reversibility. [ABSTRACT FROM AUTHOR]

Abstract: Sodium‐ion batteries (SIBs) have a promising application prospect for energy storage systems due to the abundant resource. Amorphous carbon with high electronic conductivity and high surface area is likely to be the most promising anode material for SIBs. However, the rate capability of amorphous carbon in SIBs is still a big challenge because of the sluggish kinetics of Na+ ions. Herein, a three‐dimensional amorphous carbon (3DAC) with controlled porous and disordered structures is synthesized via a facile NaCl template‐assisted method. Combination of open porous structures of 3DAC, the increased disordered structures can not only facilitate the diffusion of Na+ ions but also enhance the reversible capacity of Na storage. When applied as anode materials for SIBs, 3DAC exhibits excellent rate capability (66 mA h g−1 at 9.6 A g−1) and high reversible capacity (280 mA h g−1 at a low current density of 0.03 A g−1). Moreover, the controlled porous structures by the NaCl template method provide an appropriate specific surface area, which contributes to a relatively high initial Coulombic efficiency of 75%. Additionally, the high‐rate 3DAC material is prepared via a green approach originating from low‐cost pitch and NaCl template, demonstrating an appealing development of carbon anode materials for SIBs. [ABSTRACT FROM AUTHOR]

LiTiNbO is synthesized by a citric acid-assistant sol-gel method. X-ray diffraction (XRD) reveals that highly crystalline LiTiNbO without any impurity is obtained. The electrochemical performances of the LiTiNbO and the LiTiO in the range from 0 to 2.5 V are investigated. The LiTiNbO presents a higher specific capacity and better cycling stability than the LiTiO due to the improved conductivity. The LiTiNbO exhibits a capacity as high as 231.2 mAh g after 100 cycles, which is much higher than the LiTiO (111.1 mAh g). The effect of Nb-doping on electrochemical performance of LiTiO discharged to 0 V has also been discussed. [ABSTRACT FROM AUTHOR]

Abstract: Niobium doped lithium titanate with the composition of Li4Ti4.95Nb0.05O12 has been prepared by a sol–gel method. X-ray diffraction (XRD) and scanning electron microscope (SEM) are employed to characterize the structure and morphology of Li4Ti4.95Nb0.05O12. The Li4Ti4.95Nb0.05O12 electrode presents a higher specific capacity and better cycling performance than the Li4Ti5O12 electrode prepared by the similar process. The Li4Ti4.95Nb0.05O12 exhibits an excellent rate capability with a reversible capacity of 135mAhg−1 at 10C, 127mAhg−1 at 20C and even 80mAhg−1 at 40C. Electrical resistance measurement and electrochemical impedance spectra (EIS) reveal that the Li4Ti4.95Nb0.05O12 exhibits a higher electronic conductivity and faster lithium-ion diffusivity than the Li4Ti5O12, which indicates that niobium doped lithium titanate (Li4Ti4.95Nb0.05O12) is promising as a high rate anode for the lithium-ion batteries. [Copyright &y& Elsevier]

Fluorinated‐ethers are promising electrolyte solvents in lithium metal batteries, for their high antioxidant and excellent reductive stability on Li anode. However, fluorinated‐ethers with high fluorination degree suffer from low ionic conductivity and narrow temperature adaptibility. Herein, we synthesize a mono‐fluorinated linear ether of bis(2‐fluoroethoxy) methane (BFME) with enhanced solvated ability. The −OCH2O− structure and fluoride substitution on the β‐C position endows the BFME electrolyte with moderate affinity to Li+, thereby improving the ionic conductivity and decreasing the Li+‐desolvation energy barrier at a wide temperature range of −60–60 °C. Additionally, the electrolyte with anion‐participated solvation structure demonstrates high film‐forming ability by forming LiF‐rich interfacial film on the electrode surfaces, rendering the graphite anode with an initial Coulombic efficiency (CE) of 94.9 % and a Li plating/stripping CE of 99.8 % by Aurbach method. Consequently, the Graphite||LiFePO4 pouch cells delivered 83.2 %, 92.5 % and 81.2 % capacity retention after 1250, 200 and 300 cycles at 25, −20 °C and 60 °C, respectively. Moreover, the Li||LFP pouch cell with 3 Ah capacity can operate for 65 cycles with 99 % capacity retention, verifying the effectiveness of the BFME electrolyte in stabilizing the interfaces and broadening the temperature adaptibility of lithium‐ion and lithium metal batteries. [ABSTRACT FROM AUTHOR]

• TMSO additive effectively removes trace H 2 O and corrosive HF from the electrolyte. • TMSO increases the inorganic content in SEI/CEI layers to enhance ionic conductivity and stability. • TMSO builds a stable CEI layer to improve the SMBs stability in FEC-containing electrolytes. • SMBs exhibited remarkable electrochemical performance in the reformulated electrolyte. Rechargeable sodium batteries have become an important complement to lithium secondary batteries and other energy devices due to their lithium-like operating mechanism and abundant sodium resources. Sodium metal batteries (SMBs) with high energy density can be applied in more aspects, but still faces more prominent challenges such as sodium dendrite growth and severe electrode-electrolyte interface reactions. Fluoroethylene carbonate (FEC) additive can effectively improve the stability of sodium metal anode due to the formation of a stable solid electrolyte interfacial (SEI) layer on sodium surface. However, the protective effect is not sufficient in suppressing sodium dendrite and corrosion of electrolyte as its easily ring-opening polymerization induced by Lewis acid (especially PF 5) in carbonate electrolytes. Here, 3-Trimethylsilyl-2-oxazolidinone (TMSO) as a multifunctional additive that not only removes H 2 O and HF from the electrolyte, but also inhibits the decomposition of NaPF 6 and improves the stability of FEC-containing electrolytes. Besides, TMSO can form a stable cathode electrolyte interfacial (CEI) layer on Na 3 V 2 (PO 4) 3 (NVP) cathode surface, alleviating NVP cracking and structural pulverization and thus endowing the long-term cycling stability of NVP cathode with low interfacial resistance. Notably, with the optimized electrolyte, the Na||NVP metal battery exhibits stable cycle performance with a capacity retention of 93.1% after 1400 cycles at room temperature and higher capacity retention of 96.6% for 270 cycles at 55 °C. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Owing to the low cost and abundant resource of sodium, sodium-ion batteries demonstrate bright application prospects for large-scale energy storage systems. Microstructure-controlled amorphous carbon with proper surface area and high electronic conductivity is considered to be one of the most promising anode material. Nevertheless, the cost of the reported carbon materials is still high because of the low carbon yield and expensive precursors. Besides, the low initial coulombic efficiency is also a big challenge. Herein, a high-yielding (70%) microstructure-controlled amorphous carbon is achieved via a pre-oxidation stabilization process and following carbonization of the mixed pitch and phenol formaldehyde resin precursor. The effects of pre-oxidation stabilization on adjusting the microstructure of amorphous carbon are systematically investigated, as well as the electrochemical performance. The optimal sample exhibits high initial coulombic efficiency (82%), high reversible capacity (268.3 mAh g−1 at 0.1 C) and good rate capability (106 mAh g−1 at 4 C) as an anode material of sodium-ion batteries. This high-performance amorphous carbon material is prepared via a controllable and low-cost strategy, presenting an appealing development of practical anode materials for sodium-ion batteries. Graphical abstract Image 1 Highlights • High yielding amorphous carbon is obtained via an oxidative stabilization strategy. • In-situ FTIR spectroscopy presents the interaction between the precursors. • The controlled disordered structures lead to a high initial coulombic efficiency. • The carbon shows good electrochemical properties in both half cells and full cells. [ABSTRACT FROM AUTHOR]

SiO x is considered to be a promising anode material for lithium-ion batteries (LIBs) due to the high lithium storage capacity. However, the large initial irreversible capacity loss and intensive volume change during cycling hinder its commercial applications. Prelithiation is an effective and convenient strategy to improve the initial Coulombic efficiency (ICE) of SiO x , while incomplete and unstable SEI on the prelithiated anode still results in rapid capacity decay. Herein, through the synergy effect of chemical pre-lithiation process and fluoroethylene carbonate reduction, a compact and stable LiF-rich SEI layer is in-situ formed on the surface of prelithiated SiO x anode. The modified SiO x anode exhibits a high ICE of 90.7% with good cycling performance. When paired with the commercial LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM622) cathode, the assemble pre-Li-SiO x /C||NCM622 full cell exhibit a high ICE of 85.7% and stable cycling stability. This work provides a new insight in constructing favorable SEI in pre-lithiation process. [Display omitted] [ABSTRACT FROM AUTHOR]

Owing to the abundant resource and tunable structure, amorphous carbon materials have been widely studied as anode for alkali-metal ion batteries. However, it is still a huge space to promote their electrochemical performance for potassium ion batteries (PIBs), especially rate capability, because of the sluggish kinetics of potassium ions. In this work, 3D amorphous carbon with nitrogen and oxygen dual doping (N/O-3DC) is elaborately designed and facilely synthesized for high performance PIBs. Benefit from the synergistic effect of structural advantages, N/O-3DC electrode delivers a high reversible capacity (345 mA h g−1 at 0.03 A g−1), excellent rate performance (132 mA h g−1 at 9.6 A g−1) and ultralong lifespan (0.02% capacity decay per cycle over 1000 cycles at 3 A g−1). Combined with control experiment and structural characterization, it demonstrates the interaction between introduction of heteroatoms, construction of 3D open pore network and tailored microstructure, obtaining more active sites and enlarged interlayer spacing. Kinetic analysis and density functional theory calculations reveal dual N/O doping can not only facilitate the adsorption/desorption of K+ and elevate electronic conductivity, but also reduce energy barrier for K+ diffusion, hence promote the reaction kinetics. This work presents an appealing development of high performance carbon anode with multi-strategy coupling for PIBs. [Display omitted] • The N/O-3DC is obtained via a green approach originating from low-cost protein and facile NaCl template. • The structure design of N/O-3DC creates synergy effect for fast and stable potassium storage. • The N/O-3DC anode exhibits the superior rate performance. • The kinetic analysis and density functional theory calculations illuminate the electrochemical mechanism. [ABSTRACT FROM AUTHOR]