Rechargeable sodium-ion battery based on a cathode of copper hexacyanoferrate

Journal of Solid State Electrochemistry - In this work, the performance of copper (II) hexacyanoferrate(III) (CuHCF) as a cathode material for sodium-ion batteries was studied. The compound was...     

A low-cost lead-acid battery with high specific-energy

Lightweight grids for lead-acid battery grids have been prepared from acrylonitrile butadiene styrene (ABS) copolymer followed by coating with lead. Subsequently, the grids have been electrochemically coated with a conductive and corrosion-resistant layer of polyaniline. These grids are about 75% lighter than those employed in conventional lead-acid batteries. Commercial-grade 6V/3.5Ah (C₂₀-rate) lead-acid batteries have been assembled and characterized employing positive and negative plates constituting these grids. The specific energy of such a lead-acid battery is about 50 Wh/kg. The batteries can withstand fast charge-discharge duty cycles. Dedicated to Prof J Gopalakrishnan on his 62nd birthday.     

方铁锰矿Mn2O3作为正极材料的高比容量可充电水性锌离子电池

由于具有低成本、高安全性、组装简易方便等优点,水性可充电锌离子二次电池被认为是太阳能和风能的最佳储能装置,尤其是锌锰二次电池.目前,锰正极材料的研究较多集中在二氧化锰上,同时,也有关于Mn2O3的研究,但比容量及能量密度皆较低.本文合成了方铁锰矿Mn2O3并将其用于水性锌离子电池的正极材料,在0.2C倍率下充放时,获得...     

Structural modulation in the high capacity battery cathode material LiFeBO3

The crystal structure of the promising Li-ion battery cathode material LiFeBO(3) has been redetermined based on the results of single crystal X-ray diffraction data. A commensurate modulation that doubles the periodicity of the lattice in the a-axis direction is observed. When the structure of LiFeBO(3) is refined in the 4-dimensional superspace group C2/c(α0γ)00, with α = 1/2 and γ = 0 and with lattice parameters of a = 5.1681 ?, b = 8.8687 ?, c = 10.1656 ?, and β = 91.514°, all of the disorder present in the prior C2/c structural model is eliminated and a long-range ordering of 1D chains of corner-shared LiO(4) is revealed to occur as a result of cooperative displacements of Li and O atoms in the c-axis direction. Solid-state hybrid density functional theory calculations find that the modulation stabilizes the LiFeBO(3) structure by 1.2 kJ/mol (12 meV/f.u.), and that the modulation disappears after delithiation to form a structurally related FeBO(3) phase. The band gaps of LiFeBO(3) and FeBO(3) are calculated to be 3.5 and 3.3 eV, respectively. Bond valence sum maps have been used to identify and characterize the important Li conduction pathways, and suggest that the activation energies for Li diffusion will be higher in the modulated structure of LiFeBO(3) than in its unmodulated analogue.     

Amorphous nickel borate nanosheets as cathode material with high capacity and better cycling performance for zinc ion battery

Zinc-ion batteries are under current research focus because of their uniqueness in low cost and high safety. However, the pursuing of high-performance cathode materials of aqueous Zinc ion batteries (AZBs) with low cost, high energy density and long cycle life has become the key problem to be solved. Herein we synthesized a series of amorphous nickel borate (AM-NiBO) nanosheets by varying corrosion time with in-situ electrochemical corrosion method. The AM-NiBO-T13 as electrode material possesses a high areal capacity of 0.65 mAh/cm² with the capacity retention of 95.1% after 2000 cycles. In addition, the assembled AM-NiBO-T13//Zn provides high energy density (0.77 mWh/cm² at 1.76 mW/cm²). The high areal capacity and better cycling performance can be owing to the amorphous nanosheets structure and the stable coordination characteristics of boron and oxygen in borate materials. It shows that amorphous nickel borate nanosheets have great prospects in the field of energy storage.     

SnO2@MWCNT nanocomposite as a high capacity anode material for sodium-ion batteries

We report the synthesis and characterization of SnO₂@multiwalled carbon nanotubes (MWCNTs) nanocomposite as a high capacity anode material for sodium-ion battery. SnO₂@MWCNT nanocomposite was synthesized by a solvothermal method. SEM and TEM analyses show the uniform distribution of SnO₂ nanoparticles on carbon nanotubes. When applied as anode materials in Na-ion batteries, SnO₂@MWCNT nanocomposite exhibited a high sodium storage capacity of 839 mAh g^− 1 in the first cycle. SnO₂@MWCNT nanocomposite also demonstrated much better cycling performance than that of bare SnO₂ nanoparticles and bare MWCNTs. Furthermore, the nanocomposite electrode also showed a good cyclability and an enhanced Coulombic efficiency on cycling.     

Electrochemically activated MnO as a cathode material for sodium-ion batteries

Besides classical electrode materials pertaining to Li-ion batteries, recent interest has been devoted to pairs of active redox composites having a redox center and an intercalant source. Taking advantage of the NaPF₆ salt decomposition above 4.2 V, we extrapolate this concept to the electrochemical in situ preparation of F-based MnO composite electrodes for Na-ion batteries. Such electrodes exhibit a reversible discharge capacity of 145 mAh g^− 1 at room temperature. The amorphization of pristine MnO electrode after activation is attributed to the electrochemical grinding effect caused by substantial atomic migration and lattice strain build-up upon cycling.     

S@CNT-graphene-TiN multi-dimensional composites with high sulfur content as the high-performance lithium-sulfur battery cathode materials

Journal of Solid State Electrochemistry - S@CNT-G-TiN multi-dimensional composite materials with above 90 wt.% sulfur content were successfully synthesized via a facile suspension deposition...     

Cauliflower-like nanostructured ZnV2S4 as a potential cathode material to boost-up high capacity and durability of the aqueous zinc-ion battery

Owing to their unique design and development, high safety and low-cost efficient cathode is still at the forefront of research for rechargeable zinc-ion batteries. However, the suitable cathode operating with ultrahigh capacity with a dendrite-free anode reaction mechanism remains challenging. In this, the first archetype of a high-rate and morphologically stabled cathode material is constructed from novel cauliflower-like nano-ZnV₂S₄ for aqueous zinc-ion batteries. Thus, nano-ZnV₂S₄ was prepared with an anion exchange reaction using ZnV₂(OH)₈ cauliflower-like nanostructured array as a template interestingly no morphological and shape changes were detected. The as-prepared nano-ZnV₂S₄ electrode reveals a specific discharge capacity of 348.2 mAh/g during 0.5 A/g with enhanced rate capability and excellent capacity retention of 89.2% at 4 A/g current density even after completing 1000 cycles.     

A safe,low-cost and high-efficiency presodiation strategy for pouch-type sodium-ion capacitors with high energy density

Sodium-ion capacitors(SICs)have attracted appreciable attention in virtue of the higher energy and power densities compared with their rivals,supercapacitors and sodium-ion batteries.Due to the lack of sodium resources in cathode,presodiation is critical for SICs to further augment performances.However,current presodiation strategy utilizes metallic sodium as the presodiation material.In this strategy,assembling/disassembling of half-cells is required,which is dangerous and in creases the time and cost of SIC leading to the restriction of their industrialization and commercialization.Herein we present a safe,low-cost and high-efficiency presodiation strategy by first employing Na₂C₂O₄ as the sacrificial salt applied in SICs.Na₂C₂O₄ is environmentally friendly and possesses considerably low expenditure.No additional residues remain after sodium extraction ascribed to its"zero dead mass"property.When paired with commercial activated carb on as the cathode and commercial hard carbon as the ano de,the constructed pouch-type SICs exhibit high energy and power densities of 91.7 Wh/kg and 13.1 kW/kg,respectively.This work shows a prospect of realizing the safe and low-cost manufacturing for high-performance SICs commercially.     

High loading LiFePO<Subscript>4</Subscript> on activated carbon fiber cloth as a high capacity cathode for Li-ion battery

The LiFePO₄/carbon fiber (LFP/CF) cathodes were prepared by using activated carbon fiber cloth as current collector in place of conventional Al foil. The electrochemical properties of LFP/CF electrodes were analyzed by the cyclic voltammetry and galvanostatic charge/discharge tests. The results indicate that the activated carbon fiber cloth with high specific surface area and high porosity makes the LFP/CF electrode that possesses higher mass loading of 18–21 mg cm^–2 and stronger redox reaction ability compared with Al foil-based electrode. The LFP/CF electrode shows excellent rate performance and cycle stability. At 0.1C, the discharge capacity is up to 190.1 mAh g^–1 that exceeds the theoretical capacity due to the combination effect of battery and capacitor. Furthermore, the LFP/CF electrode shows an initial capacity of 150.4 mAh g^–1 at 1C with a capacity retention of 74.7% after 425 cycles, which is higher than 62.4% for LFP/Al foil electrode, and an initial discharge capacity of 130 mAh g^–1 at 5C with a capacity retention of 61.5% after 370 cycles. But this composite electrode is not suitable for charging/discharging at higher rate as 10C due to too much mass loading.     

A low-cost bromine-fixed additive enables a high capacity retention zinc-bromine batteries

In recent years,more and more efforts are devoting to clean energy,renewable energies in particular to achieving net zero carbon dioxide emissions[1].However,renewable energies,like solar power and wind power,are generally intermittent and random,hindering their wide application[2,3].To address this problem,there is an urgent need in effective and reliable energy storage device.     

Monodisperse porous LiFePO4 microspheres for a high power Li-ion battery cathode

A novel solvothermal approach combined with high-temperature calcinations was developed to synthesize on a large scale LiFePO(4) microspheres consisting of nanoplates or nanoparticles with an open three-dimensional (3D) porous microstructure. These micro/nanostructured LiFePO(4) microspheres have a high tap density and, as electrodes, show excellent rate capability and cycle stability.     

Capacitive charge storage enables an ultrahigh cathode capacity in aluminum-graphene battery

Aluminum^-graphene battery is promising for its abundant raw materials,high power density,ultralong cycle life and superior safety.However,the development of aluminum^-graphene battery is currently restricted by its insufficient cathode capacity,calling for a newly developed working mechanism.In addition,an irregular constant increase of the cathode capacity was always observed during cycling,but cannot be explained based on the current understanding.Here,we observed an increase of specific capacity by 60%with stable Coulombic efficiency of 98%during 7000 cycles life of Al-graphene batteries employing AlCl3/ET3NHCl electrolyte.We demonstrated this growing cathode capacity is attributed to an increasing contribution of capacitive charge storage during cycling,because a gradually enlarged surface area as capacitive active sites is enabled by the exfoliation of graphitic cathode during the periodic intercalation process.Moreover,the graphene cathode was exfoliated more significantly in AlCl3/ET3NHCl than 1-ethyl-3-methylimidazolium chloride-based electrolyte,which results from the heavier stress on the graphene layers caused by the larger intercalants in AlCl3/ET3NHCl.The common intercalation of cations with AlCl4-clusters was therefore supposed to occur during charging.This new proposed mechanism can offer the new thought for future design on high-capacity cathode of Al-ion battery.     

Enhanced reversible capacity of Li-S battery cathode based on graphene oxide

Lithium sulfur battery (LSB) offers several advantages such as very high energy density, low-cost, and environmental-friendliness. However, it suffers from serious degradation of its reversible capacity because of the dissolution of reaction intermediates, lithium polysulfides, into the electrolyte. To solve this limitation, there are many studies using graphene-based materials due to their excellent mechanical strength and high conductivity. Compared with graphene, graphene oxide (GO) contains various oxygen functional groups, which enhance the reaction with lithium polysulfides. Here, we investigated the positive effect of using GO mixed with carbon black on the performance of cathode in LSB. We have observed a smaller drop of capacity in GO mixed sulfur cathode. We further demonstrate that the mechanistic origin of reversibility improvement, as confirmed through CV and Raman spectra, can be explained by the stabilization of sulfur in lithium polysulfide intermediates by oxygen functional groups of GO to prevent dissolution. Our findings suggest that the use of graphene oxide-based cathode is a promising route to significantly improve the reversibility of current LSB.     

Polyvinylidene fluoride/polystyrene hybrid fibers with high ionic conductivity and enhanced mechanical strength as lithium-ion battery separators

Journal of Solid State Electrochemistry - Ionic conductivity is an important separator parameter influencing the cycle life and rate capability of lithium-ion batteries (LIBs). To improve the ionic...     

Synthesis of alluaudite-type Na2VFe2(PO4)3/C and its electrochemical performance as cathode material for sodium-ion battery

Journal of Solid State Electrochemistry - A new alluaudite-type Na2VFe2(PO4)3 with carbon composite has been prepared for the first time via a simple sol-gel method using citric acid as an...     

Ultrahigh rate binder-free Na_3V_2(PO_4)_3/carbon cathode for sodium-ion battery

Sodium ion batteries(SIBs)are very promising for large-scale energy storage in virtue of its high energy density,abundant sodium resources and low environmental impact,etc.However,it is still a big challenge to develop high-performance and durable cathode materials for SIBs.Among different candidate materials,Na_3V_2(PO_4)_3has attracted great attentions due to its high theoretical capacity(117 mAh/g),stable framework structure and excellent ionic conductivity.However,Na_3V_2(PO_4)_3delivers inferior rate capability and cycling stability due to its poor electronic conductivity.In this work,free-standing Na_3V_2(PO_4)_3/carbon nanofiber membranes are synthesized by an electrospinning-sintering route.The sample could deliver excellent cycling capability with specific capacity of 112 mAh/g at 1 C after 250cycles and ultrahigh rate capability with 76.9 mAh/g even at 100 C,which is superior to many state-ofthe-art SIB cathode materials.This can be attributed to the hierarchically distributed Na_3V_2(PO_4)_3crystals in carbon nanofiber network,which possesses outstanding electronic/ionic conductivity and thus leads to an ultrahigh rate capability.     

Tin phosphide-carbon composite as a high-performance anode active material for sodium-ion batteries with high energy density

Tin phosphide(Sn₄P₃)is a promising anode material for sodium-ion batteries because of its relatively large theoretical capacity,appropriate Na⁺ alloying potential,and good cyclic stability.Herein,the Sn₄P₃ embedded into a carbon matrix with good rate performance and long cycle life is reported.The Sn₄P₃-C composite exhibits excellent rate performance(540 mAh g^-1 at 5 A g^-1)and the highest reversible capacity(844 mAh g^-1 at 0.5 A ^g-1)among Sn4P3-based anodes reported so far.Its reversible capacity is as high as 705 mAh g^-1 even after 100 cycles at 0.5 A g^-1.Besides,its initial Coulomb efficiency can reach 85.6%,with the average Coulomb efficiency exceeding 99.75%from the 3rd to 100th cycles.Na₂C₆O₆ is firstly used as a cathode when Sn₄P₃ acts as anode,and the Na-Sn₄P₃-C//Na₂C₆O₆ full cell shows excellent electrochemical performance.These results demonstrate that the Sn₄P₃-C composite prepared in this work displays high-rate capability and superior cyclic performance,and thus is a potential anode for sodium ion batteries.