High-performance Rechargeable Lithium Batteries Research Articles

Ferrocene-Derived Sulfur-Rich Cathode for High-Performance Rechargeable Lithium Batteries

Ferrocene-Derived Sulfur-Rich Cathode for High-Performance Rechargeable Lithium Batteries

The role of graphene in rechargeable lithium batteries: Synthesis, functionalisation, and perspectives

In recent years, the demand for high-performance rechargeable lithium batteries has increased significantly, and many efforts have been made to boost the use of advanced electrode materials. Since graphene was first isolated by Novoselov et al., graphene/graphene-based materials have become an active area of research and are considered to be promising high-performance electrode materials. Graphene is a two-dimensional single-atom carbon-packed material that possesses fascinating properties, including a large surface area, remarkable electrical conductivity, extraordinary intrinsic electron mobility, high Young's modulus, superior mechanical strength, optical transmittance, catalytic performance, and stability. Therefore, graphene is considered an attractive material for rechargeable lithium-ion batteries (LIBs), lithium-sulfur batteries (LSBs), and lithium-oxygen batteries (LOBs). In this comprehensive review, we emphasise the recent progress in the controllable synthesis, functionalisation, and role of graphene in rechargeable lithium batteries. Finally, in this review, we aim to address the most promising results, benefits, challenges, critical issues, research directions, and perspectives to explain the developmental directions of graphene for batteries.

Supercritical CO2 Synthesis of Freestanding Se1-x S x Foamy Cathodes for High-Performance Li-Se1-x S x Battery.

Selenium-sulfur solid solutions (Se1-xSx) are considered to be a new class of promising cathodic materials for high-performance rechargeable lithium batteries owing to their superior electric conductivity than S and higher theoretical specific capacity than Se. In this work, high-performance Li-Se1-xSx batteries employed freestanding cathodes by encapsulating Se1-xSx in a N-doped carbon framework with three-dimensional (3D) interconnected porous structure (NC@SWCNTs) are proposed. Se1-xSx is uniformly dispersed in 3D porous carbon matrix with the assistance of supercritical CO2 (SC-CO2) technique. Impressively, NC@SWCNTs host not only provides spatial confinement for Se1-xSx and efficient physical/chemical adsorption of intermediates, but also offers a highly conductive framework to facilitate ion/electron transport. More importantly, the Se/S ratio of Se1-xSx plays an important role on the electrochemical performance of Li- Se1-xSx batteries. Benefiting from the rationally designed structure and chemical composition, NC@SWCNTs@Se0.2S0.8 cathode exhibits excellent cyclic stability (632 mA h g−1 at 200 cycle at 0.2 A g−1) and superior rate capability (415 mA h g−1 at 2.0 A g−1) in carbonate-based electrolyte. This novel NC@SWCNTs@Se0.2S0.8 cathode not only introduces a new strategy to design high-performance cathodes, but also provides a new approach to fabricate freestanding cathodes towards practical applications of high-energy-density rechargeable batteries.

Electrospun Silsequioxane-grafted PVDF hybrid membranes for high-performance rechargeable lithium batteries

Microporous electrospun membranes have certain advantages of higher porosities and electrolyte wettability owing to their high specific surface areas, but these materials suffer from insufficient mechanical strength and dimensional stability when they are employed in advanced lithium batteries. In order to improve the material characteristics and electrochemical performance of these materials, we report the fabrication of silsesquioxane modified electrospun hybrid poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF(HFP)) membranes via the combination of concurrent electrospinning/electrospraying techniques and a UV-initiated grafting polymerization method. The fabricated electrospun hybrid membranes were systematically characterized via various techniques, including thermal characterization, morphology observation, dimensional and mechanical property tests, as well as electrochemical measurements. Silsesquioxanes were covalently integrated onto the surface of electrospun fibers to obtain rigid sheath-like hybrid shell architectures and enhanced cross-linked networks, thus imparting these electrospun hybrid membranes with superior mechanical properties, thermal and dimensional stabilities, as well as remarkable electrochemical performance. Through an in-depth investigation into the electrochemical performance differential of separator prepared by different molecular-topological silsesquioxanes, we discovered that octa-silsesquioxanes (SQ-T8) decorated separators offered superior cycling performance while deca-silsesquioxanes (SQ-T10) exhibited a higher capacity. Through these investigations, we hypothesized that SQ-T8 and SQ-T10 assembled into different configurations via intermolecular stacking arrangements as they were grafted onto electrospun fibers. On the basis of these promising results, these electrospun hybrid membranes could find practical applications in advanced lithium batteries.

A Highly Immobilized Organic Anode Material for High Performance Rechargeable Lithium Batteries.

Organic conjugated carbonyl materials have attracted considerable attention in the field of high-capacity and green energy storage technologies. However, the high solubility in organic electrolyte restrains their further application. In this work, an organic terephthalate compound (Li2M) with propargyl groups is synthesized innovatively and then used to prepare a highly cross-linked anode material (X-Li2M) by simple hydrothermal treatment for rechargeable lithium batteries. The electrochemical properties are enhanced significantly by in situ constructing an interpenetrating network of X-Li2M and the conductive carbon nanotubes (CNTs). The as-synthesized X-Li2M@CNTs composite anode delivers a reversible capacity of ∼200 mAh g-1 at 0.1 C after 200 cycles and exhibits excellent cycle stability at a high rate of 1 C with ∼150 mAh g-1 retention capacity after 1000 cycles and nearly 100% average Coulombic efficiency. Additionally, the superior rate capability is obtained at the high rate of 2 and 10 C and with specific discharge capacities of 140 and 100 mAh g-1, respectively. Highly reversible redox reaction of the electrochemical active site carbonyl group (C═O) is ascertained by ex-situ infrared spectroscopy and X-ray photoelectron spectroscopy. The described approach provides a novel direction for the immobilization of organic electrode molecules and is intended to serve as a universal guide for the research and fabrication of high-performance organic batteries.

A Novel Strategy to Functionalize Covalent Organic Frameworks for High-Energy Rechargeable Lithium Organic Batteries via Graft Polymerization in Nano-Channels

Abstract By introducing catalyst- and solvent-free graft polymerization of low cost and environmentally benign sulfur to the nano-channels of an imine-linked covalent organic framework (COF), we demonstrated our strategy for functionalization of a conventional COF to yield a redox-active covalent organic framework-graft-polysulfide (COF-graft-PS), which can be utilized as a cathode active material in rechargeable lithium organic batteries. The COF-graft-PS-based batteries showed high capacity (425 mA h g−1 at a rate of 250 mA g−1), excellent rate capability, and good cycling performance over 500 cycles. The design characteristics and synthetic strategy open new possibilities for the preparation of alternative, sustainable, high-performance rechargeable lithium batteries by using abundant and cost-effective materials.

A facial method to synthesize Se/NiO composites for high performance lithium ion battery electrodes

Analogous to the element sulfur in Li-S battery, Selenium (Se) has similar capabilities which attracted considerable attention for lithium ion battery (LIB) electrodes. However, a large volume expansion induced by Li-ion insertion limits the application of Se electrodes. In this paper, Se/NiO nanocomposites were prepared by a simple wet chemical method at a low temperature. Benefiting from the favorable macro/meso-nanosheets arrays structures, Se/NiO nanocomposites can greatly ease the capacity loss caused by volume expansion, which exhibited excellent rate performances.These results indicate that the Se/NiO nanocomposite is a promising electrode material for high performance rechargeable lithium batteries.

Unique electrochemical behavior of heterocyclic selenium–sulfur cathode materials in ether-based electrolytes for rechargeable lithium batteries

Mixed chalcogenide systems represent a new class of promising cathode materials for high performance rechargeable lithium batteries. Among them, heterocyclic selenium–sulfur (SexSy) cathodes, coupling the good conductivity of Se and high capacity of S, have attracted great attention in recent years. However, further research is still needed to better understand the lithiation/delithiation process of SexSy cathodes in ether-based electrolytes. Herein, SexSy-based composites with covalent Se–S bonds were prepared by infiltrating various proportions of S and Se powders into the mesoporous carbon microsphere (MCM) host at 500°C in vacuum. As cathodes for rechargeable lithium batteries, SexSy/MCM composites exhibit unique electrochemical behavior rather than a simple hybrid of Li–S and Li–Se batteries in ether-based electrolytes. The Se–S bonds in SexSy/MCM could anchor S during cycling, and effectively reduce the formation of long-chain polysulfides. As a result, the SexSy/MCM cathodes demonstrate superior overall electrochemical performance than Se/MCM or S/MCM. Moreover, Se/S ratio could also affect the electrochemical behavior of SexSy/MCM composites. The optimal Se2S5/MCM cathode delivers the best performance with a high reversible capacity of 796.4mAhg−1 at 0.5C over 100 cycles, and good rate capability of 688.8mAhg−1 at 5C. Especially, a superior coulombic efficiency of ~100% is achieved without addition of LiNO3. This work could help us to better understand the inherent synergistic mechanism behind SexSy cathodes for high performance rechargeable lithium batteries in ether-based electrolytes.

Multifunctional Nitrogen-Doped Loofah Sponge Carbon Blocking Layer for High-Performance Rechargeable Lithium Batteries.

Low-cost, long-life, and high-performance lithium batteries not only provide an economically viable power source to electric vehicles and smart electricity grids but also address the issues of the energy shortage and environmental sustainability. Herein, low-cost, hierarchically porous, and nitrogen-doped loofah sponge carbon (N-LSC) derived from the loofah sponge has been synthesized via a simple calcining process and then applied as a multifunctional blocking layer for Li-S, Li-Se, and Li-I2 batteries. As a result of the ultrahigh specific area (2551.06 m(2) g(-1)), high porosity (1.75 cm(3) g(-1)), high conductivity (1170 S m(-1)), and heteroatoms doping of N-LSC, the resultant Li-S, Li-Se, and Li-I2 batteries with the N-LSC-900 membrane deliver outstanding electrochemical performance stability in all cases, i.e., high reversible capacities of 623.6 mA h g(-1) at 1675 mA g(-1) after 500 cycles, 350 mA h g(-1) at 1356 mA g(-1) after 1000 cycles, and 150 mA h g(-1) at 10550 mA g(-1) after 5000 cycles, respectively. The successful application to Li-S, Li-Se, and Li-I2 batteries suggests that loofa sponge carbon could play a vital role in modern rechargeable battery industries as a universal, cost-effective, environmentally friendly, and high-performance blocking layer.

Promising graphene/carbon nanotube foam@π-conjugated polymer self-supporting composite cathodes for high-performance rechargeable lithium batteries

Three-dimensional (3D) graphene foam materials are highly favored due to large accessible surface and excellent conductive network, which can be commendably applied as self-supporting electrodes for advanced rechargeable lithium batteries (RLBs). Here, promising graphene nanosheets/acid-treated multi-walled carbon nanotubes (GNS/aMWCNT)-supported 1,5-diaminoanthraquinone (DAA) organic foams [oGCTF(DAA)] are prepared by organic solvent displacement method followed by solvothermal reaction. And then electrochemical polymerization is carried out to obtain 3D porous GNS/aMWCNT organic foam-supported poly(1,5-diaminoanthraquinone) (oGCTF@PDAA) nanocomposites, which achieves the ordered growth of homogeneous PDAA nanoparticles on GNS/aMWCNT surface due to the role of oGCTF(DAA). Such structure largely improves PDAA utilization, facilitates charge transportation and suppresses the dissolution of PDAA. As a result, the oGCTF@PDAA cathode for RLBs delivers a high discharge capacity of 289mAhg−1 at 30mAg−1 and still retains 122mAhg−1 at extreme 10Ag−1 for rapid charging/discharging. Moreover, superior cycling stability is achieved with only 14.8% capacity loss after 2000 cycles even at a high current density of 1Ag−1.

FeS2 microspheres with an ether-based electrolyte for high-performance rechargeable lithium batteries

FeS2 microspheres assembled with nanoplates show long cycling stability and high rate performance as the cathode for rechargeable Li batteries in an optimized ether-based electrolyte.

Surface modification of LiV3O8 nanosheets via layer-by-layer self-assembly for high-performance rechargeable lithium batteries

In this work, an economical route based on hydrothermal and layer-by-layer (LBL) self-assembly processes has been developed to synthesize unique Al2O3-modified LiV3O8 nanosheets, comprising a core of LiV3O8 nanosheets and a thin Al2O3 nanolayer. The thickness of the Al2O3 nanolayer can be tuned by altering the LBL cycles. When evaluated for their lithium-storage properties, the 1 LBL Al2O3-modified LiV3O8 nanosheets exhibit a high discharge capacity of 191 mA h g−1 at 300 mA g−1 (1C) over 200 cycles and excellent rate capability, demonstrating that enhanced physical and/or chemical properties can be achieved through proper surface modification.

Combination of acid-resistor and -scavenger improves the SEI stability and cycling ability of tin–nickel battery anodes in LiPF6-containing electrolyte

Control of electrode–electrolyte interfacial reactivity and the formation of the solid electrolyte interphase (SEI) layer is a key technology for high performance rechargeable lithium batteries. Here we present the first report on a promising interfacial approach for Sn–Ni electrode that the use of acid-resisting and -scavenging fluorine-dopant on Sn combined with acid-scavenging trimethyl phosphite electrolyte additive to LiPF6-contiaing carbonate-based organic electrolyte improves the interfacial stability of Sn to acidic electrolyte species. As a result, a stable SEI layer consisting of a plenty of carbonate decomposition products forms and cycling ability significantly improves, in contrast to less efficient SEI formation and rapid performance fade for the electrodes without fluorine-dopant or trimethyl phosphite additive.

Novel Antimony/Aluminum/Carbon Nanocomposite for High-Performance Rechargeable Lithium Batteries

A simple method of transforming micrometer-sized Al and Sb powders into a new nanocomposite modified with carbon by the alloying reaction of Al and Sb to form the AlSb phase and the dealloying reaction of the AlSb phase with carbon to synthesize the Sb/Al4C3/C nanocomposite was developed using a high-energy mechanical milling technique. The Sb/Al4C3/C nanocomposite was confirmed, using various analytical techniques, to be composed of a reduced crystalline Sb phase, amorphous Al4C3 phase, and amorphous carbon. This novel nanocomposite showed a highly reversible reaction with Li, a high capacity of 687 mAh g−1 with a good Coulombic efficiency of 85% for the first cycle, and a high capacity retention above 520 mAh g−1 over 200 cycles. Additionally, by controlling the voltage window, an excellent cyclability with a high rate capability also was achieved. These excellent electrochemical properties demonstrated by the Sb/Al4C3/C nanocomposite electrode confirm its potential as a new alternative anode material for Li-ion batteries.

PVDF–PEO/ZSM-5 based composite microporous polymer electrolyte with novel pore configuration and ionic conductivity

A novel composite microporous polymer electrolyte based on poly(vinylidene fluoride), poly(ethylene oxide), and microporous molecular sieves ZSM-5 (denoted as PVDF–PEO/ZSM-5) was prepared by a simple phase inversion technique. PEO can obviously improve the pore configuration, such as pore size, porosity, and pore connectivity of PVDF-based microporous membranes, results in a high room temperature ionic conductivity. Microporous molecular sieves ZSM-5 can further improve the mechanical strength of PVDF–PEO blends and form special conducting pathway in PVDF–PEO matrix by absorb liquid electrolyte in its two-dimensional interconnect channels. The high room temperature ionic conductivity combined with good mechanical strength implies that PVDF–PEO/ZSM-5 based composite microporous polymer electrolyte can be used as candidate electrolyte and/or separator material for high-performance rechargeable lithium batteries.

PVDF–PEO blends based microporous polymer electrolyte: Effect of PEO on pore configurations and ionic conductivity

A novel microporous polymer electrolyte based on poly(vinylidene fluoride) and poly(ethylene oxide) (PVDF–PEO) blends was prepared by a simple phase inversion technique, in which the addition of PEO can obviously improve the pore configuration, such as pore size, porosity, and pore connectivity of PVDF-based microporous membranes, and hence, the room temperature ionic conductivity was greatly enhanced. The highest porosity of about 84% and ionic conductivity of about 2 mS cm −1 can be obtained when the weight ratio of PEO to PVDF is 50%. This implies that PVDF–PEO blends based microporous polymer electrolyte can be used as candidate electrolyte and/or separator material for high-performance rechargeable lithium batteries.