Functional Mesoporous Carbon‐Coated Separator for Long‐Life, High‐Energy Lithium–Sulfur Batteries

Abstract

The lithium–sulfur (Li–S) battery is regarded as the most promising rechargeable energy storage technology for the increasing applications of clean energy transportation systems due to its remarkable high theoretical energy density of 2.6 kWh kg−1, considerably outperforming today's lithium‐ion batteries. Additionally, the use of sulfur as active cathode material has the advantages of being inexpensive, environmentally benign, and naturally abundant. However, the insulating nature of sulfur, the fast capacity fading, and the short lifespan of Li–S batteries have been hampered their commercialization. In this paper, a functional mesoporous carbon‐coated separator is presented for improving the overall performance of Li–S batteries. A straightforward coating modification of the commercial polypropylene separator allows the integration of a conductive mesoporous carbon layer which offers a physical place to localize dissolved polysulfide intermediates and retain them as active material within the cathode side. Despite the use of a simple sulfur–carbon black mixture as cathode, the Li–S cell with a mesoporous carbon‐coated separator offers outstanding performance with an initial capacity of 1378 mAh g−1 at 0.2 C, and high reversible capacity of 723 mAh g−1, and degradation rate of only 0.081% per cycle, after 500 cycles at 0.5 C.

Mechanism and Solution for the Capacity Fading of Li/FeS2Battery

“…[46][47][48] The most significant improvement was found to be the use of a carbon interlayer, which was applied by employing a carbon-coated separator with the carbon layer facing the FeS 2 cathode. As indicated by curve-d, the carbon interlayer extended the cycle life up to about 200 cycles, which can be attributed to the bi-function of the carbon interlayer: [49][50][51] (1) confining the dissolved Li 2 S n from out-diffusion on the cathode, and (2) reducing the parasitic reactions with the dissolved Li 2 S n on the anode. Even with the improvement of three strategies above, the capacity of these Li/FeS 2 cells was still poorly remained due to the continuous loss of sulfur active material and the progressive growth of resistive Li surface layer, caused by the unavoidable dissolution of Li 2 S n in an organic electrolyte and the irreversible reduction of the dissolved Li 2 S n to insoluble Li 2 S 2 /Li 2 S on the Li anode.…”

Role of 1,3-Dioxolane and LiNO3Addition on the Long Term Stability of Nanostructured Silicon/Carbon Anodes for Rechargeable Lithium Batteries

“…14-18 The Li-S system is a primary candidate to boost the use of green energy in electro mobility, [19][20][21] but cannot be used in combination with carbonate-based electrolytes due to the incompatibility with soluble polysulfides. 22 Ether-based solutions, typically mixtures of dimethoxy ethane (DME) and 1,3-dioxolane (DOL), turned out to be an ideal electrolyte system for Li-S batteries owing to its compatibility with polysulfides and good dissolution properties for bis(trifluoromethane)sulfonamide lithium (Li-TFSI) as typical conductive salt, but its effect on silicon anodes has been rarely studied yet.…”

“…[10][11][12][13] However, in recent years silicon proved to be an advanced anode not only in LIB, but also in the next generation lithium -sulfur (Li-S) battery as replacement for lithium metal anodes. [14][15][16][17][18] The Li-S system is a primary candidate to boost the use of green energy in electro mobility, [19][20][21] but cannot be used in combination with carbonate-based electrolytes due to the incompatibility with soluble polysulfides. 22 Ether-based solutions, typically mixtures of dimethoxy ethane (DME) and 1,3-dioxolane (DOL), turned out to be an ideal electrolyte system for Li-S batteries owing to its compatibility with polysulfides and good dissolution properties for bis(trifluoromethane)sulfonamide lithium (Li-TFSI) as typical conductive salt, but its effect on silicon anodes has been rarely studied c Present address: Erich Schmid Institute of Materials Science, Austrian Academy of Sciences, A-8700 Leoben, Austria.…”

Strong affinity of polysulfide intermediates to multi-functional binder for practical application in lithium–sulfur batteries

“…These result in low sulfur utilization, low coulombic efficiencies, and rapid capacity fading of Li-S batteries [6][7][8][9][10][11][12]. Many strategies have been applied to Li-S batteries to address these scientific issues in the past few years, mainly focusing on the construction of nanostructured sulfur cathode [13][14][15][16][17][18] and functionalization of the separator [19][20][21][22][23][24].…”