Binder-free cathodes based on sulfur–carbon nanofibers composites for lithium–sulfur batteries

Abstract

Binder-free cathodes based on sulfur–carbon nanofiber composites were prepared through a liquid process and showed good performance for lithium–sulfur batteries.

Composite Nanofibers as Advanced Materials for Li-ion, Li-O2 and Li-S Batteries

“…These drawbacks notwithstanding, the nanofiber revolution hold a great promise to the energy storage industry. 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 [222], Nitrogen doped carbon nanofiber web/sulfur composite electrode (c) [247] and CNFs with sulfur coating(d) [230]. Reproduced with permission from Power Sources, Electrochimica Acta and Nano Lett.…”

“…These properties of the carbon nanofiber-sulfur based cathodes form ideal inter wound reservoir-like matrices that accommodate active sulfur [123,153,[224][225][226][227][228][229][230][231][232][233][234][235][236][237][238][239][240], while the porous structure ideally confine/trap the active sulfur and its soluble polysulfides, which can greatly reduce the shuttle effect. In addition, the carbon nanofibers improve the mechanical/ structural integrity of the composite electrode as well as the conductivity, [232,233,238] that further enhances electrons/ Li + transfer and improves sulfur utilization in Li-S batteries [123,153,[224][225][226][227][228][229][230][231][232][233][234][235][236][237][238][239][240] and by extension, improves the batteries electrochemical performance. The challenge however, on the use of these carbon nanofiber-sulfur-based cathodes in Li-S batteries is the inconsistency of the fiber surface area, particularly those produced by electrospinning [225,226,…”

Poly(4‐styrene sulfonic acid) to Disperse Graphene for Applications in Lithium‐Sulfur Batteries

“…The poor conductivity of S not only decreases the specific capacity and energy density of the fabricated cells, but also results in a high ohmic potential drop (IR drop) that fades the cells very rapidly . A great deal of research into possible solutions to these problems has been carried out . For example, the use of highly conductive graphene‐based materials has been reported to be effective for improving the electrochemical performance of the Li−S battery.…”

Facile Synthesis of Hierarchical Sulfur Composites for Lithium–Sulfur Batteries

“…However, S also presents a number of challenges that have to be overcome, such as its low electrical conductivity (5 × 10-30 S cm À 1 ), [15] the shuttle effect caused by easy dissolution of the intermediates (high-order polysulfide (PS) species) generated during discharge, [16][17][18][19][20] and the high volume expansion (80 %). [23][24][25][26][27][28][29][30][31][32][33][34] One frequently adopted method is to produce a composite of S and a carbonaceous material. In addition, volume expansion of S can occur during its discharge/lithiation process, which may cause high mechanical stress that damages the cathode.…”

“…[21] The shuttle effect, relating to the dissolution of high-order PS species that are produced as electrochemical intermediates in a polar electrolyte and the followed migration to the lithium anode due to the concentration gradient, results in a continual loss of the active S material from the cathode and thus the eventual decay of the capacity. Carbonaceous materials, including graphene, [23][24][25] graphite, [26] carbon fibers, [27] carbon nanotubes, [28][29][30][31] and carbon nanoparticles, [34] have long been reported to efficiently improve electronic conductivity of S; additionally, the carbon defects were reported to be helpful in inhibiting the PS dissolution and the shuttle effect. [21] The poor electrical conductivity of S, which is also one of pressing issues for the commercialization of LiÀ S batteries, not only results in low capacity and energy density in the batteries, but also causes a high ohmic potential drop that leads to rapid cell fading.…”