No abstract

No abstract

The commercialization of lithium‐sulfur (Li‐S) batteries is greatly hindered due to serious capacity fading caused by the polysulfide shuttling effect. Optimizing the structural configuration, enhancing reaction kinetics of the sulfur cathode, and increasing areal sulfur loading are of great significance for promoting the commercial applications of Li‐S batteries. Herein, the multifunctional polysulfide scavengers based on nitrogen, sulfur co‐doped carbon cloth (DCC), which is supported by flower‐like MoS2 (1T‐2H) decorated with BaMn0.9Mg0.1O3 perovskite particle (PrNP) and carbon nanotubes (CNTs), namely, DCC@MoS2/PrNP/CNTs, are delicately designed and synthesized. The physical confinement, chemical coupling, and catalysis conversion for active sulfur are achieved simultaneously in this polysulfide motif. Due to these merits, the as‐fabricated self‐supported DCC@MoS2/PrNP/CNTs/S manifests an excellent reversible areal capacity of 4.75 mAh cm−2 with an ultrahigh sulfur loading of 5.2 mg cm−2 at the 50th cycle. The outstanding cycling stability is obtained upon 800 cycles with a large reversible capacity of 871 mAh g−1 and a negligible fading rate of 0.02% per cycle at a rate of 1.0 C, suggesting its promising prospects for the commercial success of high‐performance Li‐S batteries toward flexible electronic devices and energy storage equipment.

A crucial challenge for the commercialization of Ni-rich layered cathodes (LiNi0.88Co0.09Al0.03O2) is capacity decay during the cycling process, which originates from their interfacial instability and structural degradation. Herein, a one-step, dual-modified strategy is put forward to in situ synthesize the yttrium (Y)-doped and yttrium orthophosphate (YPO4)-modified LiNi0.88Co0.09Al0.03O2 cathode material. It is confirmed that the YPO4 coating layer as a good ion conductor can stabilize the solid–electrolyte interface, while the formative strong Y–O bond can bridle TM–O slabs to intensify the lattice structure in the state of deep delithium (>4.3 V). In particular, both the combined advantages effectively withstand the anisotropic strain generated upon the H2–H3 phase transition and further alleviate the crack generation in unit-cell dimensions, assuring a high-capacity delivery and fast Li+ diffusion kinetics. This dual-modified cathode shows advanced cycling stability (94.1% at 1C after 100 cycles in 2.7–4.3 V), even at a high cutoff voltage and high rate, and advanced rate capability (159.7 mAh g–1 at 10C). Therefore, it provides a novel solution to achieve both high capacity and highly stable cyclability in Ni-rich cathode materials.

High Ni-low Co layered oxides are considered as the most promising next generation cathode material for high energy density lithium ion battery in order to fulfil the demand of 300...

No abstract

Li-rich layered oxides (LLOs) with high specific capacities are favorable cathode materials with high-energy density. Unfortunately, the drawbacks of LLOs such as oxygen release, low conductivity, and depressed kinetics for lithium ion transport during cycling can affect the safety and rate capability. Moreover, they suffer severe capacity and voltage fading, which are major challenges for the commercializing development. To cure these issues, herein, the synthesis of high-performance antimony-doped LLO nanofibers by an electrospinning process is put forward. On the basis of the combination of theoretical analyses and experimental approaches, it can be found that the one-dimensional porous micro-/nanomorphology is in favor of lithium-ion diffusion, and the antimony doping can expand the layered phase lattice and further improve the lithium ion diffusion coefficient. Moreover, the antimony doping can decrease the band gap and contribute extra electrons to O within the LiMnO phase, thereby enhancing electronic conductivity and stabilizing lattice oxygen. Benefitting from the unique architecture, reformative electronic structure, and enhanced kinetics, the antimony-doped LLO nanofibers possess a high reversible capacity (272.8 mA h g) and initial coulombic efficiency (87.8%) at 0.1 C. Moreover, the antimony-doped LLO nanofibers show excellent cycling performance, rate capability, and suppressed voltage fading. The capacity retention can reach 86.9% after 200 cycles at 1 C, and even cycling at a high rate of 10 C, a capacity of 172.3 mA h g can still be obtained. The favorable results can assist in developing the LLO material with outstanding electrochemical properties.

No abstract