Silicon‐Rich Carbon Hybrid Nanofibers from Water‐Based Spinning: The Synergy Between Silicon and Carbon for Li‐ion Battery Anode Application

Abstract

Hybrid carbon nanofibers (NFs) with extremely high Si loading (>65 wt %) are fabricated through the water‐based electrospinning of polyvinyl alcohol/Si nanoparticle (NP) solutions for Li‐ion battery anode applications. Our Si‐rich carbon (SRC) NFs show many facilitated charge‐transport features and increased activities because of the continuous one‐dimensional (1D) carbon backbone structure with dispersed Si NP domains. This leads to superior battery performance compared to that of bare silicon NPs. The presence of carbon as 1D NFs can not only mitigate the volume change of silicon but also avoid the formation of an unstable solid‐electrolyte interface on the surface of silicon. Our study, regarding the optimum combination of C and Si in the NFs for their improved electrochemical properties and battery performance, reveals that SRC NFs containing 72.8 wt % Si (27.2 wt % C) exhibit an adequate balance between the high energy capacity of Si NPs and the dimensional stability and effective charge transport of carbon NFs. This optimum Si/C ratio leads to an outstanding cycle life, which maintains 1076 mAh g−1 capacity normalized by the total electrode mass, and a Coulombic efficiency of about 99 % over 50 cycles. Such scalable SRC NFs produced through the water‐based spinning approach can offer a cost‐effective development for high‐performance battery anodes.

Foamed mesoporous carbon/silicon composite nanofiber anode for lithium ion batteries

“…By introducing appropriate carbon nanofiber (CNF) manufacturing approaches (i.e., electrospinning polymer nanofibers and then carbonized into CNFs), Ji et al successfully produced CNF-based LIBs electrodes with low cost and high throughput [20e22]. These CNFs with one-dimensional nanostructure and interconnected network, offer more surface area and space than graphite to allow quick lithium ion transport between electrolytes and the active materials [23,24]. Li-active elements (e.g., Si, Ni, Cu, and Fe) were also conveniently introduced into CNFs in some cases to promote Li insertion/extraction efficiency [25e27].…”

Complementary X-ray and neutron radiography study of the initial lithiation process in lithium-ion batteries containing silicon electrodes

“…The broad cathodic peak at around 1.0 V for both radio-cell and coin cell, as well as the cathodic peak at 2.0 V for radiocell are intimately related to the side electrolyte decomposition of forming the solid electrolyte interface (SEI) during first cathodic scan[21]. A characteristic cathodic peak at around 0 V is suggestive of alloy formation of Li with Si[22]. During the following anodic scan, the anodic peaks at around 0.4 V and 1.0 V can be attributed respectively to the Li-Si de-alloying reaction and the oxidation reaction of byproduct compounds reduced at cathodic process[23].…”

Nanostructured electrode materials for lithium-ion and sodium-ion batteries via electrospinning

“…On the other hand, Si nanoparticles (0D) encapsulated in CNFs (1D) is one promising strategy to accommodate the volume change of Si [108][109][110][111]. Zhou et al [112] prepared one Si@PCNF hybrid material with Si nanoparticles encapsulated in PCNFs via a single-nozzle electrospinning technique as shown in Fig.…”