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1.
A non-aqueous Li/organosulfur semi-solid flow battery is constructed. The battery with a high cell voltage of 3.36 V achieves coulombic efficiency of 99%, voltage efficiency of 73% and energy efficiency of 72% at the current density of 5 mA/cm2.  相似文献   

2.
A simple and novel methodology was developed for manufacturing interdigitated asymmetric all-solid-state flexible micro-supercapacitors (MSCs) by a facile pencil drawing process followed by electrodepositing MnO2 on one of the as-drawn graphite electrode as anode and the other as cathode.  相似文献   

3.
High lithiation capacity at low red-ox potentials in combination with good safety characteristics makes amorphous Si as a very promising anode material for rechargeable Li batteries.Thin film silicon electrodes were prepared by DC magnetron sputtering of silicon on stainless steel substrates. Their behavior as Li insertion/extraction electrodes was studied by voltammetry and chronopotentiometry at room temperature in the ionic liquid (IL) 1-methyl-1-propylpiperidinium bis(trifluoromethylsuphonil)imide containing 1 M Li bis(trifluoromethylsuphonil)imide. Li/Si cells containing this electrolyte showed good performance with a stable Si electrodes capacity of about 3000 mA h g−1 and a relatively low irreversible capacity. Preliminary results on cycling Si–LiCoO2 cells using this IL electrolyte are also presented.  相似文献   

4.
In this work, large area MOF-derived ZnCo2O4/C anchored on carbon fiber as high-performance anode materials was fabricated via a facile method and subsequent annealing treatment.  相似文献   

5.
An interwoven core–shell structured Ni/NiO anode for lithium ion batteries was created by a simple oxidation of Ni foam. As-prepared configuration has a high specific discharge capacity of 701 mAh g?1 at the 2nd cycle. Its electrochemical performance at subsequent cycles shows good energy capacity of 646 mAh g?1 at the 65th cycle as well as good rate capability. The porous core–shell structure not only buffers the volume change during cycling but also effectively increases the contact among anode, current collector and electrolyte. The small contact resistance between NiO and Ni facilitates enhanced intrinsic kinetics from conversion reaction.  相似文献   

6.
《中国化学快报》2020,31(5):1217-1220
Because of their high capacity and low potential, lithium metal anodes are considered to be promising candidates for next generation electrode materials. However, the safety concerns and limited cycling life associated with uncontrollable dendrite growth hamper practical applications. In this work, the acidified cellulose ester, which is a mixed fiber microporous membrane film, was used as a novel electrolyte additive that effectively improves the cycle stability of the lithium metal anode and inhibits dendrite growth. The focus of this paper is on inhibiting the formation and growth of lithium dendrites. The coulombic efficiency of a Li|Cu battery with this acidified cellulose ester additive remains stable at 99% after 500 cycles under a current density of 1 mA/cm2. Symmetric batteries also remain stable after 500 cycles (1000 h) under a current density of 1 mA/cm2. These superior properties can be ascribed to the induced nucleation and the uniform distribution of lithium ion flux. This study uncovers an approach for effectively enabling stable cycling of dendrite-free lithium metal anodes.  相似文献   

7.
We report on the self-supported, two-dimensional (2D) SnS nanosheets electrode directly grown on metallic current collectors via non-catalytic and template-free, vapor transport synthetic route. The self-supported SnS nanosheets electrode demonstrates good cycling performance and superior rate capabilities: a capacity of ~380 mAh g?1 even at 20C rate (after charging for 3 min), larger than the theoretical capacity of the carbon-based electrodes currently used in commercial Li ion batteries. The origin of such an improvement in the long-term cycle stability and electronic/ionic transport kinetics, is understood by means of various microscopic investigation as well as unique characteristics of self-supported nanostructuring strategy itself.  相似文献   

8.
Two different approaches were tried for an improvement of the cycle performance of Li–S cells: (1) A mixed polymer binder system of polyvinyl pyrrolidone (PVP) and polyethyleneimine (PEI) was developed to maintain the initial morphology of the carbon electrodes, the positive electrode of the Li–S cells, during charge–discharge cycles; (2) a tetrabutylammonium (TBA)-based mixed salt system was applied to an organic liquid electrolyte of the Li–S cells to change certain chemical reactions of polysulfides in the electrolyte solutions. The Li–S cells with PEI showed a significant improvement in cycle performance as well as in discharge capacity, compared with the Li–S cells using PVP only. The discharge capacity at the 50th cycle was found to be ∼580 mAh/g-sulfur, 83% of an initial capacity (∼720 mAh/g-sulfur), at a high current density of 2.0 mA cm−2. It was observed that the Li–S cells with a mixed electrolyte of 0.5 M LiCF3SO3/0.5 M TBAPF6 did not show a distinct improvement in the aspect of discharge capacity. The Li–S cells, however, showed a significant enhancement in the cycle life characteristics much better than that of Li–S cells with 1.0 M LiCF3SO3.  相似文献   

9.
A novel Cu-SnO2 anode material derived from Cu6Sn5 alloy, retaining high conductivity of Cu and high theoretical capacity of SnO2 with a facile synthesizing process by oxidation and reduction method. The novel Cu structure penetrates in the composite particles inducing high conductivity and spaceconfined SnO2, which restrict the pulverization of SnO2 during lithiation/delithiation process.  相似文献   

10.
Mesopores tubular graphene, synthesized by template method, have unique bi-directional ions transfer channel in unstack graphene layers and high mesopore ratio, exhibiting excellent capacitance performance in the EDLC using ionic liquid electrolyte at 4 V.  相似文献   

11.
In this study, the electrochemical performance of PbO@C core–shell nanocomposites as an anode material of lithium-ion batteries was reported. The PbO@C nanocomposites were prepared via the pyrolysis of lead benzoate precursor. Compared to the reported Pb-based anodes, the PbO@C nanocomposites exhibited higher reversible capacity and longer cycling life. A reversible capacity of 170 mAh g?1 could be maintained after discharging/charging for 50 cycles, which was at least 1.5 times than the previously reported values. The enhanced electrochemical performance was attributed to the presence of carbon shells that could alleviate the large volume-change of Pb particles during the alloying/dealloying process.  相似文献   

12.
A high performance hybrid ion capacitors has been developed by using B, N dual-doped 3D superstructure carbon cathode and prelithiated graphite anode.  相似文献   

13.
Carbon nanosprings (CNSs) with spring diameter of ~140 nm, carbon ring diameter of ~100 nm and pitch distance of ~150 nm, synthesized by using a catalytic chemical vapor deposition technology, have been investigated for potential applicability in lithium batteries as anode materials. The electrochemical results demonstrate that the present CNSs are superior anode materials for rechargeable lithium-ion batteries with high-rate capabilities, as well as long-term cycling life. At a current density as high as 3 A g?1, CNSs can still deliver a reversible capacity of 160 mA h g?1, which is about six times larger than that of graphite and three times larger than that of multi-wall carbon nanotubes under the same current density. After hundreds of cycles, there is no significant capacity loss for CNSs at both low and high current densities. The much improved electrochemical performances could be attributed to the nanometer-sized building blocks as well as the unusual spring-like morphology.  相似文献   

14.
Li metal is considered an ideal anode material because of its high theoretical capacity and low electrode potential. However, the practical usage of Li metal as an anode is severely limited because of inevitable parasitic side reactions with electrolyte and dendrites formation. At present, single-component artificial solid electrolyte interphase cannot simultaneously meet the multiple functions of promoting ion conduction, guiding lithium ion deposition, inhibiting dendrite growth, and reducing ...  相似文献   

15.
Novel category LiMnSnO4 compound was synthesized via. Urea assisted combustion (UAC) method at 800 °C and examined for possible use as cathode material in lithium-ion batteries. The XRD (X-ray diffraction) results of LiMnSnO4 sample authenticate the orthorhombic crystal structure with high degree of crystallinity. Presence of uniformly distributed nanometric grains (scanning electron microscopy) with preferred local cation environment is evident from FT IR (Fourier transform infra red spectroscopic) and 7Li NMR (nuclear magnetic resonance spectroscopy) studies. The charge–discharge behavior of Li/LiMnSnO4 cells demonstrated a specific capacity of 113 mA h/g, with an excellent capacity retention (95%) and Ah efficiency (>99%). Besides, the internal resistance of the Li/LiMnSnO4 cell after 30 cycles is negligibly small, thus demonstrating good electronic conductivity and cycling stability, required for any lithium intercalating cathode material.  相似文献   

16.
The use of Li metal as the anode for Li-based batteries has attracted considerable attention due to its ultrahigh energy density. However, the formation of Li dendrites, uneven deposition, and huge volume changes hinder its reliable implementation. These issues become much more severe in commercial carbonate-based electrolytes than in ether-based electrolytes. Herein, a rationally designed three-dimensional graphene/Ag aerogel (3D G-Ag aerogel) is proposed for Li metal anodes with long cycle life in carbonate-based electrolytes. The modified lithiophilic nature of G-Ag aerogel, realized through decoration with Ag NPs, effectively decreases the energy barrier for Li nucleation, regulating uniform Li deposition behavior. Moreover, the highly flexible, conductive 3D porous architecture with hierarchical mesopores and macropores can readily accommodate deposited Li and ensures the integrity of the conductive network during cycling. Consequently, high coulombic efficiency (over 93.5 %) and a significantly long cycle life (1589 h) over 200 cycles, with a relatively high cycling capacity of 2.0 mAh cm−2, can easily be achieved, even in a carbonate-based electrolyte. Considering the intrinsic high voltage windows of carbonate-based electrolytes, matching the G-Ag aerogel Li metal anode with a high-voltage cathode can be envisaged for the fabrication of high-energy-density Li secondary batteries.  相似文献   

17.
Li(Ni1/3Co1/3Mn1/3)O2 microspheres with a tap density of 2.41 g cm−3 have been synthesized for applications in high power and high energy systems, using a simple rheological phase reaction route. Cyclic voltammograms (CV) showed no shift of anodic and cathodic peaks centred at 3.81, 3.69 V for the Ni2+/Ni4+ couple after first cycle. The results of power pulse area specific impedance (ASI) and differential scanning calorimetry (DSC) tests showed lower power impedance and increased thermal stability of the electrode at high rate. These merits mentioned above provided significant improved capacity and rate performance for Li(Ni1/3Co1/3Mn1/3)O2 microspheres, which 159, 147 mAh g−1 discharge capacity was delivered after 100 cycles between 2.5–4.6 V vs. Li at a different discharge rate of 2.5 C (500 mA g−1), 5 C and a constant 0.5 C charge rate, respectively.  相似文献   

18.
Crystalline nanoparticles of LiCoO2 are prepared by a sol–gel method at 550 °C and characterized by X-ray diffraction. Their electrochemical behaviors were characterized by cyclic voltammograms, capacity measurement and cycling performance. Results show that the reversible capacity of the nano-LiCoO2 can be up to 143 mAh/g at 1000 mA/g and still be 133 mAh/g at 10,000 mA/g (about 70C) in 0.5 mol/l Li2SO4 aqueous electrolyte. In addition, their cycling behavior is also very satisfactory, no evident capacity fading during the initial 40 cycles. These data present great promise for the application of aqueous rechargeable lithium batteries.  相似文献   

19.
The mesoporous carbon material with large pore volume and high surface area by a simple situ MgO template method is synthesized, which is utilized as cathode to assemble a high performance lithium ion capacitor.  相似文献   

20.
Hexagonal Li2MgSnO4 compound was synthesized at 800 °C using Urea Assisted Combustion (UAC) method and the same has been exploited as an anode material for lithium battery applications. Structural investigations through X-ray diffraction, Fourier Transform Infra Red spectroscopy and 7Li NMR (Nuclear Magnetic Resonance spectroscopy) studies demonstrated the existence of hexagonal crystallite structure with a = 6.10 and c = 9.75. An average crystallite size of ∼400 nm has been calculated from PXRD pattern, which was further evidenced by SEM images. An initial discharge capacity of ∼794 mA h/g has been delivered by Li2MgSnO4 anode with an excellent capacity retention (85%) and an enhanced coulombic efficiency (97–99%). Further, the Li2MgSnO4 anode material has exhibited a steady state reversible capacity of ∼590 mA h/g even after 30 cycles, thus qualifying the same for use in futuristic lithium battery applications.  相似文献   

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