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• A Box-Behnken design for graphite anodes slurries optimization was presented to highlight the importance of the component's interactions to obtained higher performed anodes of lithium-ion batteries customization. • The carbon black content is the most significant effect in both materials which is reflected in higher capacities and coulombic efficiencies. • For the overall behavior, the binder/carbon black interactions are relevant in terms not only of electrochemical performance but also in the obtention of more homogeneous and better adhesion anodes. The technological application of lithium-ion batteries (LIB) grows constantly, making customization of the batteries a current necessity and sometimes a challenge. In this paper we described carbon-slurry optimization process for anodes of lithium-ion batteries customization by using a surface response statistical experiment with four response variables such specific discharge capacity, coulombic efficiency, anodes mass deviation, and capacity retention. We studied two commercial graphite active materials by characterizing the materials via Raman spectroscopy, SEM, and electrochemical techniques. We corroborate the graphite structure for both materials but with morphological differences such as shape and particle size. The binder composition seems to interfere with the active carbon materials capabilities while it generates better performance for one of them. Although the chemical structure of both materials was confirmed to be the same via Raman experiments, SEM images shows critical morphological differences that interferes with the final slurry thus, affecting the electrochemical performance of the anodes. Further studies are required to understand ECSA and its possible effect on the charge/discharge capacities of the anodes. [Display omitted] [ABSTRACT FROM AUTHOR]

This work presents a comprehensive analysis of the impact of carbon nanotubes (CNT) and carbon nanofibers (CNF) composition on the performance of nano-Si anodes in lithium-ion batteries. The nano-Si anode suffers from chemo-mechanical issues caused by its large volumetric change (e.g., 280%) during cycling. One of the promising solutions in electrode level is to establish a robust electronic conduction pathway in Si anodes by incorporating CNT and CNF with high aspect ratios. The objective of this work is to quantitatively measure the performance improvement achieved by CNT and CNF based on their compositions and analyze the improvement mechanism through electrochemical methods. The results indicate that substituting a portion of carbon black with CNT and CNF in a range of 1 – 10 wt% can enhance the capacity retention (from 44% to around 60%) and the fast-charging and fast-discharging capabilities. Electrochemical impedance spectroscopy (EIS) and distribution of relaxation times (DRT) analyses revealed that 5% – 10% CNT and CNF conductors effectively suppressed contact impedances growths in Si anodes. In summary, our findings highlight the importance of precise control over the composition of CNT and CNF to achieve good electrode morphology and electrochemical properties for nano-Si anodes. [ABSTRACT FROM AUTHOR]

• Nanosized VC was synthesized by disproportionation of V(IV) ions in molten salt. • The VC powder have excellent dispersibility and uniform size distribution. • The VC exhibits desirable electrochemical performances as an anode in LIBs and SIBs. • It is a new insight into the synthesis of high-performance carbide as anode in metal-ion batteries. Nanosized VC with an average particle size of ∼40 nm was synthesized by disproportionation of V(IV) ions on acetylene black template in molten (Na,K)Cl at 950 °C holding for 5 h. The as-synthesized VC has exhibited desirable electrochemical performances as an anode in lithium-ion batteries (LIBs), delivered a reversible discharge capacity of 597.8 mAh g−1 at 0.1 A g−1 and ∼397.8 mAh g−1 at 0.5 A g−1 in 200 consecutive cycles. It is noteworthy that nanosized VC also displayed impressive charge-discharge capacities in sodium-ion batteries (SIBs), released ∼252.5 mAh g−1 at 0.1 A g−1. This work provides a new insight into the preparation of high-performance carbide ceramics as anodes in metal-ion batteries. [Display omitted] Well-distributed nanosized VC was synthesized by a convenient and efficient synthesis method, utilizing disproportionation reaction of V(IV) in molten salt, exhibits excellent electrochemical performances in lithium ion batteries. [ABSTRACT FROM AUTHOR]

A nano-sized Si anode material was synthesized by a novel and highly efficient route of ball-milling assisted low-temperature aluminothermic reduction at 150–180 °C in a eutectic NaCl/KCl/AlCl 3 mixture, using white carbon black and coarse-grained Al powder as the starting materials. After extending the duration of ball-milling assisted aluminothermic reduction to 10 h, the obtained Si yield reached as high as 94%. The synthesized nano-Si mainly consisted of irregular porous agglomerates constructed by ultrafine primary particles with a particle size less than 50 nm. The nano-Si anode showed a superior electrochemical performance. Its maximum discharge and charge capacities at a current density of 0.05 A g−1 were 3075 and 2597 mAh g−1, respectively, leading to a high initial Coulumbic efficiency of 84.5%. The nano-Si anode exhibited reversible capacities of 2458 mAh g−1 at 0.2 A g−1, and of 1169 mAh g−1 at a high current density of 5 A g−1. After cycling at 1 A g−1 for 400 cycles, it still delivered a high reversible capacity of 804 mAh g−1. The synthetic strategy, which is not only facile and highly efficient, but also low-cost and environmentally benign, is thus promising to be applied for mass production of nano-Si anode materials for next-generation Li-ion batteries. [ABSTRACT FROM AUTHOR]