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In this study, binder-free tungsten oxide carbon nanofibers and graphene oxide composites (WO3 CNFs/GO) were prepared as self-supporting anodes for lithium-ion batteries (LIBs) by applying a one-step electrostatic spinning technology. Owing to the combination of WO3 CNFs (WCF) and graphene oxide (GO), the composites exhibit excellent performance by suppressing expansion during the cycle. WO3 CNFs (WCF) provide excellent continuity and uniform width, and the GO adhered to the WCF forms a cross-linked conductive network and an internal mesoporous environment, which reduces the diffusion distance of electrons/ions and facilitates charge transfer. In addition, the disordered arrangement of WO3 CNFs (WCFs) can increase the porosity and increase the contact area with the electrolyte, which is more favorable for electrolyte penetration. The WO3 CNF/GO (WCFG) anode had a specific capacity of 644.6 mA h g−1 after 250 cycles. [ABSTRACT FROM AUTHOR]

Silicon–carbon nanofibers-carbonized yeast powder composite (SCNFs/CYP) was fabricated using the electrostatic spinning and hydrothermal processes. Experimental results show that the carbon nanofibers can restrain the volume expansion of silicon in the electrochemical process and the microporous structure of carbonized yeast powder can increase the specific surface area and promote the penetration of electrolyte. The compound was cyclically tested at charge–discharge rate of 0. 5 ∘ C, and the first charge/discharge capacity was 1725 and 1732 mAh/g. Although it is lower than the capacity of single structure silicon–carbon nanofibers (SCNFs), with the increase of the number of cycles, the capacity of charging and discharging has been greatly improved, and it can be maintained at 1656 mAh/g after 180 cycles. The R CT after 1 cycle, 10 cycles and 100 cycles were 486, 286.5 and 231 Ω , from which we can see that the SCNFs–CYP has lower overall impedance values as the cycle increases. This indicated that the addition of carbon nanofibers and carbonized yeast powder inhibited the volume expansion and increased the specific surface area, providing more electrical contact sites. [ABSTRACT FROM AUTHOR]

Metal sulfide demonstrated sluggish ionic transport kinetics due to the low electronic conductively, resulting larger volume expansion and even pulverize electrode during Li+ insertion/deinsertion. In this study, freestanding SnS nanoflower@carbon nanofiber (SnS@CNF) was prepared by the sol‐gel electrospinning of hydrothermal synthesized SnS2 nanoflower and carbonization. When direct used SnS@CNF as a binder‐free negative electrode for LIB, it delivered specific capacity of 564.4 mAh g−1@0.3 C after 450 cycles, and high rate capacities of 595, 465, 354, 267, 200, 129, 74, and 484 mAh g−1 at the current densities of 0.064, 0.1, 0.3, 0.6, 1.0, 1.5, 2.0, and 0.1 mA g−1, respectively. Such excellent electrochemical performance is attributed to the nanostructured conductive CNF network not only can buffer volume expansion and prevents the aggregation of active material, but also improve Li+ migration rates during the discharge (4.47×10−7 cm2 s−1) and charge (2.73×10−6 cm2 s−1) process. [ABSTRACT FROM AUTHOR]