Two-dimensional layered transition metal disulphides for effective encapsulation of high-capacity lithium sulphide cathodes

Seh, Zhi Wei; Yu, Jung Ho; Li, Weiyang; Hsu, Po‐Chun; Wang, Haotian; Sun, Yongming; Yao, Hong‐Bin; Zhang, Qianfan; Cui, Yi

doi:10.1038/ncomms6017

Cited by 544 publications

(325 citation statements)

References 66 publications

Supporting

Mentioning

315

Contrasting

Order By: Relevance

“…3C). This low fading rate is the best observed among all lithium/ sulfur batteries, either nonaqueous or aqueous (5,7). Even at a low charge/discharge rate of 0.2C, which has always been a challenge not only for the Li/S system but for all aqueous systems, the capacity decay was still only 9% after 100 cycles (Fig.…”

Section: Resultsmentioning

confidence: 95%

Unique aqueous Li-ion/sulfur chemistry with high energy density and reversibility

Yang

Suo

Borodin

et al. 2017

Proc. Natl. Acad. Sci. U.S.A.

171

182

View full text Add to dashboard Cite

Leveraging the most recent success in expanding the electrochemical stability window of aqueous electrolytes, in this work we create a unique Li-ion/sulfur chemistry of both high energy density and safety. We show that in the superconcentrated aqueous electrolyte, lithiation of sulfur experiences phase change from a highorder polysulfide to low-order polysulfides through solid-liquid two-phase reaction pathway, where the liquid polysulfide phase in the sulfide electrode is thermodynamically phase-separated from the superconcentrated aqueous electrolyte. The sulfur with solid-liquid two-phase exhibits a reversible capacity of 1,327 mAh/(g of S), along with fast reaction kinetics and negligible polysulfide dissolution. By coupling a sulfur anode with different Li-ion cathode materials, the aqueous Li-ion/sulfur full cell delivers record-high energy densities up to 200 Wh/(kg of total electrode mass) for >1,000 cycles at ∼100% coulombic efficiency. These performances already approach that of commercial lithium-ion batteries (LIBs) using a nonaqueous electrolyte, along with intrinsic safety not possessed by the latter. The excellent performance of this aqueous battery chemistry significantly promotes the practical possibility of aqueous LIBs in large-format applications.water-in-salt | rechargeable aqueous battery | aqueous sulfur battery | gel polymer electrolyte | phase separation I n the past two decades, rechargeable lithium-ion batteries (LIBs) have revolutionized consumer electronics with their high energy density and excellent cycling stability, and are the state-of-the-art candidates for applications ranging from kilowatt hours for electric vehicles up to megawatt hours for grids (1, 2). The latter applications in large-format present much more stringent requirements for safety, cost, and environmental friendliness, besides energy density and cycle life. The shortcomings of LIB are mostly due to the flammable and toxic nonaqueous electrolytes and moderate energy densities (<400 Wh·kg −1 ) provided by the electrochemical couples currently used (3). Among the various "beyond Li-ion" high-energy chemistries (>500 Wh·kg −1 ) explored currently, the nonaqueous lithium/sulfur (Li/S) battery based on sulfur as a cathode (theoretical capacity of 1,675 mAh·g −1 ) and metallic lithium as an anode seems to be the most practical, as evidenced by the mushrooming literature and significant advances in this system in the past 5 y (4-7). However, commercialization of this system still faces challenges because of severe safety concerns associated with the dendrite growth of metallic Li anode in highly inflammable ether-based electrolytes (8), and the high self-discharge associated with parasitic shuttling of the intermediate polysulfide species. Moreover, the moisture-sensitive nature of the nonaqueous electrolyte would contribute significantly to the cost of the Li/S battery pack due to the stringent moisture-exclusion infrastructure required during the manufacturing, processing, and packaging of the cells. The indispensabl...

show abstract

Section: Resultsmentioning

confidence: 95%

Unique aqueous Li-ion/sulfur chemistry with high energy density and reversibility

Yang

Suo

Borodin

et al. 2017

Proc. Natl. Acad. Sci. U.S.A.

171

182

View full text Add to dashboard Cite

show abstract

“…This is what typical shuttle mechanism describes. Enormous efforts have been dedicated to overcome the shuttle issue, most of which focused on cathode, including (1) designing nanostructured conductive carbon5 or polymer scaffold6 to confine LiPSs, (2) employing inorganic yet conductive materials for enhancing the adsorption and surface redox chemistry of LiPSs,7 and (3) tailoring reduction pathway and chemical formulation of polysulfide complex by tuning the coordination capability of electrolyte solvents 8. Although previous works have made huge success, the dissolution of LiPSs seems to be barely evitable in conventional ether‐based liquid electrolytes.…”

Section: Introductionmentioning

confidence: 99%

Janus Separator of Polypropylene‐Supported Cellular Graphene Framework for Sulfur Cathodes with High Utilization in Lithium–Sulfur Batteries

et al. 2015

View full text Add to dashboard Cite

Owing to the conversion chemistry of the sulfur cathode, the lithium–sulfur (Li–S) batteries exhibit high theoretical energy density. However, the intrinsic mobile redox centers during the sulfur/Li2S‐to‐lithium polysulfides solid‐to‐liquid phase transition induce low sulfur utilization and poor cycling life. Herein, the Janus separator of mesoporous cellular graphene framework (CGF)/polypropylene membrane to promote the utilization of sulfur cathode is introduced. The porous polypropylene membrane serves as an insulating substrate in contact with lithium anode while CGFs that possess high electrical conductivity of 100 S cm−1, a large mesopore volume of 3.1 cm3 g−1, and a huge surface area of 2120 m2 g−1 are adhered on cathode side to reactivate the shuttling‐back polysulfides and to preserve the ion channels. Therefore, the Li–S cell with the “two‐face” CGF Janus separator exhibit a high initial capacity of 1109 mAh g−1 and superior capacity preserved upon 800 mAh g−1 after 250 cycles at 0.2 C, which is 40% higher on sulfur utilization efficiency than the corresponding results with routine polypropylene separators. There are significant improvements on capacity as well as electrochemical kinetics. A very high areal capacity of 5.5 mAh cm−2 combined with high sulfur content of 80% and areal loading amount of 5.3 mg cm−2 is achieved for such advanced configuration. The negative impact of shuttle mechanism on lowering the utilization of sulfur and overall energy density of a Li–S battery is well eliminated by applying CGF separators. Consequently, employing carbonaceous materials as Janus face of separators enlightens new opportunities for improving the utilization of active materials and energy density of devices that involve complex phase evolution and conversion electrochemistry.

show abstract

“…The well‐known challenges for Li–S batteries are associated with two main aspects: (1) poor ion and electron transport dynamics due to the uncontrolled dissolution of complex sulfur species and the insulating nature of sulfur ( σ = 5 × 10 −30 S cm −1 )11 and its reduction compounds, sulfides ( σ = 10 −13 S cm −1 );12, 13 (2) loss of active materials into electrolytes stemming from the shuttling of soluble lithium polysulfide (LiPS) intermediates. The poor conductivity limits the accessibility of active cathode materials and the insolubility nature in most organic solvents hinders the oxidation reactions.…”

mentioning

confidence: 99%

Chloride‐Reinforced Carbon Nanofiber Host as Effective Polysulfide Traps in Lithium–Sulfur Batteries

et al. 2016

View full text Add to dashboard Cite

Lithium–sulfur (Li–S) battery is one of the most promising alternatives for the current state‐of‐the‐art lithium‐ion batteries due to its high theoretical energy density and low production cost from the use of sulfur. However, the commercialization of Li–S batteries has been so far limited to the cyclability and the retention of active sulfur materials. Using co‐electrospinning and physical vapor deposition procedures, we created a class of chloride–carbon nanofiber composites, and studied their effectiveness on polysulfides sequestration. By trapping sulfur reduction products in the modified cathode through both chemical and physical confinements, these chloride‐coated cathodes are shown to remarkably suppress the polysulfide dissolution and shuttling between lithium and sulfur electrodes. From adsorption experiments and theoretical calculations, it is shown that not only the sulfide‐adsorption effect but also the diffusivity in the vicinity of these chlorides materials plays an important role on the reversibility of sulfur‐based cathode upon repeated cycles. Balancing the adsorption and diffusion effects of these nonconductive materials could lead to the enhanced cycling performance of an Li–S cell. Electrochemical analyses over hundreds of cycles indicate that cells containing indium chloride‐modified carbon nanofiber outperform cells with other halogenated salts, delivering an average specific capacity of above 1200 mAh g−1 at 0.2 C.

show abstract

Two-dimensional layered transition metal disulphides for effective encapsulation of high-capacity lithium sulphide cathodes

Cited by 544 publications

References 66 publications

Unique aqueous Li-ion/sulfur chemistry with high energy density and reversibility

Unique aqueous Li-ion/sulfur chemistry with high energy density and reversibility

Janus Separator of Polypropylene‐Supported Cellular Graphene Framework for Sulfur Cathodes with High Utilization in Lithium–Sulfur Batteries

Chloride‐Reinforced Carbon Nanofiber Host as Effective Polysulfide Traps in Lithium–Sulfur Batteries

Contact Info

Product

Resources

About