Silicon nanowires(Si NWs)have been widely researched as the best alternative to graphite anodes for the next-generation of high-performance lithium-ion batteries(LIBs)owing to their high capacity and low discharge pot...Silicon nanowires(Si NWs)have been widely researched as the best alternative to graphite anodes for the next-generation of high-performance lithium-ion batteries(LIBs)owing to their high capacity and low discharge potential.However,growing binder-free Si NW anodes with adequate mass loading and stable capacity is severely limited by the low surface area of planar current collectors(CCs),and is particularly challenging to achieve on standard pure-Cu substrates due to the ubiquitous formation of Li+inactive silicide phases.Here,the growth of densely-interwoven In-seeded Si NWs is facilitated by a thin-film of copper-silicide(CS)network in situ grown on a Cu-foil,allowing for a thin active NW layer(<10μm thick)and high areal loading(≈1.04 mg/cm^(2))binder-free electrode architecture.The electrode exhibits an average Coulombic efficiency(CE)of>99.6%and stable performance for>900 cycles with≈88.7%capacity retention.More significantly,it delivers a volumetric capacity of≈1086.1 m A h/cm^(3)at 5C.The full-cell versus lithium manganese oxide(LMO)cathode delivers a capacity of≈1177.1 m A h/g at 1C with a stable rate capability.This electrode architecture represents significant advances toward the development of binder-free Si NW electrodes for LIB application.展开更多
Fast charging and high volumetric capacity are two of the critical demands for sodium-ion batteries(SIBs).Although nanostructured materials achieve outstanding rate performance,they suffer from low tap density and sma...Fast charging and high volumetric capacity are two of the critical demands for sodium-ion batteries(SIBs).Although nanostructured materials achieve outstanding rate performance,they suffer from low tap density and small volumetric capacity.Therefore,how to realize large volumetric capacity and high tap density simultaneously is very challenging.Here,N/F co-doped TiO_(2)/carbon microspheres(NF- TiO_(2)/C)are synthesized to achieve both of them.Theoretical calculations reveal that N and F co-doping increases the contents of oxygen vacancies and narrows the bandgaps of TiO_(2) and C,improving the electronic conductivity of NF- TiO_(2)/C.Furthermore,NF- TiO_(2)/C exhibits the high binding energy and low diffusion energy barrier of Na+,significantly facilitating Na+storage and Na+diffusion.Therefore,NF- TiO_(2)/C offers a high tap density(1.51 g cm^(-3)),an outstanding rate performance(125.9 mAh g^(-1) at 100 C),a large volumetric capacity(190 mAh cm^(-3) at 100 C),a high areal capacity(4.8 mAh cm^(-2))and an ultra-long cycling performance(80.2%after 10,000 cycles at 10 C)simultaneously.In addition,NF- TiO_(2)/C||Na_(3)V_(2)(PO_(4))_(3) full cells achieve an ultrahigh power density of 25.2 kW kg^(-1).These results indicate the great promise of NF- TiO_(2)/C as a high-volumetric-capacity and high-power-density anode material of SIBs.展开更多
The development of lithium-metal batteries(LMBs)is seriously restricted by the out-of-control dendrites growth and infinite volume expansion.Herein,a pervasive organic-inorganic layer construction strategy is reported...The development of lithium-metal batteries(LMBs)is seriously restricted by the out-of-control dendrites growth and infinite volume expansion.Herein,a pervasive organic-inorganic layer construction strategy is reported for the composite lithium metal anode with congener-derived organic-inorganic solid electrolyte interphase(SEI).In this strategy,the organic-inorganic Ag@polydopamine(Ag@PDA)layer is coated on the arbitrary substrates by a simple two-step method.The thin and stable congener-derived SEI is insitu formed with fewer inorganic components and more organic components during charging/discharging.The polydopamine with sufficient adhesion groups and lithiophilic Ag layer realize near-zero nucleation overpotential during lithium deposition.The low interface resistance and stable lithium deposition are achieved.Moreover,the practical areal and volumetric capacities of the composite anode with three-dimensional copper(3DCu)as the substrate are 10 mAh/cm^(2)and 1538 mAh/cm^3(vs.the mass of anode).The symmetrical cell shows very low polarization voltage(10 mV)and more than 2500 h cycles life at 1 mA/cm^(2)(1 mAh/cm^(2)).The LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)-based full cells show improved capacity retention(82%)after 100 cycles at 0.5 C.The modified lithiophilic anode with congener-derived interphase provides a promising strategy to realize the next-generation dendrite-free LMBs.展开更多
Aqueous zinc-ion batteries(AZIBs)have emerged as promising candidates for next-generation energy storage systems due to their inherent safety,cost-effectiveness,and high theoretical capacity.However,their practical ap...Aqueous zinc-ion batteries(AZIBs)have emerged as promising candidates for next-generation energy storage systems due to their inherent safety,cost-effectiveness,and high theoretical capacity.However,their practical application remains constrained by limited cycling stability and sluggish ion diffusion kinetics,particularly under high mass loading conditions.These limitations are primarily attributed to the restricted ion transport pathways within the electrode structure and structural degradation caused by repeated zinc-ion insertion and extraction in highly loaded electrodes.To address these challenges,formamide(FA)-inserted VOPO_(4)(FA-VOPO_(4))nanosheet cathodes were designed with expanded interlayer spacing(9.3Å),where FA molecules partially replace interlayer water,thereby enhancing both structural stability and ion transport pathways.This unique structural modification,supported by synergistic hydrogen bonding between FA and residual water,significantly improves Zn2+diffusion kinetics and charge transfer properties,as confirmed by electrochemical tests and theoretical analysis.Consequently,FA-VOPO_(4)electrodes delivered a remarkable volumetric capacity of 733 mAh/cm^(3)at 40 mA/g,approximately 8 times higher than that of the VOPO_(4)·2H_(2)O electrode,and retained 82.1%of their capacity after 1000 cycles at 1 A/g with a mass loading of 10 mg/cm^(2).Even at a high mass loading of 20 mg/cm^(2)(4.4 mAh/cm^(2)),the FA-VOPO_(4)cathode maintained a volumetric capacity of 535 mAh/cm^(3).These findings provide valuable insights into electrode design strategies for high-performance AZIBs,contributing to the development of safer,more efficient energy storage technologies with potential applications in grid storage and portable electronics.展开更多
To meet the growing demand for high-energy-density lithium-ion batteries(LIBs),silicon(Si)anodes have gained attention as a promising material for next-generation anodes owing to their ultrahigh gravimetric capacity.N...To meet the growing demand for high-energy-density lithium-ion batteries(LIBs),silicon(Si)anodes have gained attention as a promising material for next-generation anodes owing to their ultrahigh gravimetric capacity.Nevertheless,the Si anode faces significant challenges,particularly severe volume expansion during cycling,which leads to rapid capacity degradation and greatly hinders its commercialization potential.Although extensive research has focused on mitigating volume changes and constructing stable solid-electrolyte interphases on Si-based anodes,a crucial factor for practical application,namely the volumetric capacity,has been often overlooked.For Si-based anodes to replace conventional graphite anodes,their volumetric capacity must be thoroughly evaluated.Key factors determining the volumetric capacity include gravimetric capacity,active material mass ratio,initial Coulombic efficiency,electrode swelling ratio,and the negative-to-positive capacity ratio.This paper systematically analyzes,discusses,and summarizes each of these factors in detail.Common issues with existing strategies are identified,and future research directions concerning the commercialization of Si-based anodes are outlined.This study provides a systematic and novel perspective on effectively modifying and designing Si-based anodes,aiming to promote the volumetric capacity toward the large-scale industrialization of next-generation LIBs.展开更多
Low volumetric energy density is a bottleneck for the application of lithium-sulfur (Li-S)battery.The low- density sulfur cooperated with the light-weight carbon sub- strate realizes electrochemical cycle stability,bu...Low volumetric energy density is a bottleneck for the application of lithium-sulfur (Li-S)battery.The low- density sulfur cooperated with the light-weight carbon sub- strate realizes electrochemical cycle stability,but leads to worse volumetric energy density.Here,nickel ferrite (NiFe2O4)nanofibers as novel substrate for sulfur not only anchor lithium polysulfides to enhance the cycle stability of sulfur cathode,but also contribute to the high volumetric capacity of the S/nickel ferrite composite.Specifically,the S/ nickel ferrite composite presents an initial volumetric capacity of 1,281.7mA h cm^-3-composite at 0.1C rate,1.9times higher than that of S/carbon nanotubes,due to the high tap density of the S/nickel ferrite composite.展开更多
Exploring high-capacity electrode materials is critical for the development of K-ion batteries.In this work,we report a layered-structured tungsten selenide(WSe2)anode,which not only delivers an ultrahigh volumetric c...Exploring high-capacity electrode materials is critical for the development of K-ion batteries.In this work,we report a layered-structured tungsten selenide(WSe2)anode,which not only delivers an ultrahigh volumetric capacity of 1772.8 Ah/L(or 188.4 mAh/g)at a current density of 5 mA/g but also exhibits good rate capability(72 mAh/g at 200 mA/g)and cycling stability(83.14%capacity retention over 100 cycles at 100 mA/g).We have also revealed the underlying reaction mechanism through ex situ X-ray powder diffraction.Furthermore,proof-of-concept full-cell batteries comprising of WSe2 anodes and Prussian Blue cathodes are capable of delivering an energy density of 135.2 Wh/kgcathode+anode.This work highlights the potential of WSe2 as a promising high-volumetric-capacity anode material for rechargeable potassium-ion batteries.展开更多
The use of air conditioning and refrigeration systems improved the standard of living. However, the system contributes to global warming by releasing potential global warming refrigerants directly and powering the sys...The use of air conditioning and refrigeration systems improved the standard of living. However, the system contributes to global warming by releasing potential global warming refrigerants directly and powering the system. There is an obligation, like UN Kyoto Protocol, EU MAC Directive and Japan METI Directive to find an alternative low-GWP refrigerant with excellent thermophysical properties. In this paper, the global warming effect of an air-conditioning system is analyzed theoretically using few low-GWP refrigerant mixtures. New refrigerant mixtures are formed based on low GWP, high volumetric capacity, and refrigerating effect. After analyzing, refrigerant blends of R1234yf/R32 (40/60, 50/50, and 60/40 by wt%) and R1234ze/R32 (40/60, 50/50, and 60/40 by wt%) are found promising to replace the widely used R410A. The best performance of the refrigerant blend is found for R1234yf/R32 (40/60). These analyses are crucial for selecting suitable refrigerants for domestic air conditioning systems.展开更多
Hydrogen storage is a critical component in transition to clean energy systems and the promotion of sustainable practices across various industries.The primary technical challenge lies in designing adsorbent materials...Hydrogen storage is a critical component in transition to clean energy systems and the promotion of sustainable practices across various industries.The primary technical challenge lies in designing adsorbent materials that effectively balance both volumetric and gravimetric storage capabilities while ensuring operational reliability.Achieving this balance is essential for the efficient and practical application of hydrogen in fuel-based systems.Recently,in Nature Chemistry,Stoddart et al.introduced a straightforward and precise method:multivalent hydrogen bonding facilitates molecular linkage at defined nodal points in hydrogen-bonded organic frameworks(HOFs).This methodology demonstrates simultaneous optimization of hydrogen storage performance,achieving notable volumetric(53.7 g/L)and gravimetric(9.3 wt%)capacities under dynamic thermo-pressure cycling conditions.展开更多
The silicon oxide nano-powders (SiO<sub>x</sub>-NPs) were obtained in an atmospheric microwave plasma torch using a gas-phase silicon tetrachloride (SiCl<sub>4</sub>) with N<sub>2</sub...The silicon oxide nano-powders (SiO<sub>x</sub>-NPs) were obtained in an atmospheric microwave plasma torch using a gas-phase silicon tetrachloride (SiCl<sub>4</sub>) with N<sub>2</sub> and H<sub>2</sub>. The gas-phase SiCl<sub>4</sub> was injected with H<sub>2</sub> gas into the microwave plasma torch generated by N<sub>2</sub> and air swirl gas, and then the dark brown powders were deposited on the inner wall of a quartz tube. The sample was analyzed by an X-ray photoelectron spectroscopy (XPS), a scanning electron microscope (SEM), an energy dispersive spectrometer (EDS), and an X-ray diffraction (XRD). The average size and oxidation x values of synthesized SiO<sub>x</sub>-NPs were approximately 230 nm and 0.91, respectively. Furthermore, the volumetric charge capacity is 1127 mAh/g and has 89.2% retention after 100 cycles.展开更多
Ultra-thick,dense alloy-type anodes are promising for achieving large areal and volumetric performance in potassium-ion batteries(PIBs),but severe volume expansion as well as sluggish ion and electron diffusion kineti...Ultra-thick,dense alloy-type anodes are promising for achieving large areal and volumetric performance in potassium-ion batteries(PIBs),but severe volume expansion as well as sluggish ion and electron diffusion kinetics heavily impede their widespread application.Herein,we design highly dense(3.1 g cm^(-3))Ti_(3)C_(2)T_(x) MXene and graphene dual-encapsulated nano-Sb monolith architectures(HD-Sb@Ti_(3)C_(2)T_(x)-G)with high-conductivity elastic networks(1560 S m^(-1))and compact dually encapsulated structures,which exhibit a large volumetric capacity of 1780.2 mAh cm^(-3)(gravimetric capacity:565.0 mAh g^(-1)),a long-term stable lifespan of 500 cycles with 82%retention,and a large areal capacity of 8.6 mAh cm^(-2)(loading:31 mg cm^(-2))in PIBs.Using ex-situ SEM,in-situ TEM,kinetic investigations,and theoretical calculations,we reveal that the excellent areal and volumetric performance mechanism stems from the three dimensional(3D)high-conductivity elastic networks and the dualencapsulated Sb architecture of Ti_(3)C_(2)T_(x) and graphene;these effectively mitigate against volume expansion and the pulverization of Sb,offering good electrolyte penetration and rapid ionic/electronic transmission.Ti_(3)C_(2)T_(x) also decreases the Kþdiffusion energy barrier,and the ultra-thick compact electrode ensures volumetric and areal performance.These findings provide a feasible strategy for fabricating ultra-thick,dense alloy-type electrodes to achieve high areal and volumetric capacity energy storage via highly-dense,dual-encapsulated architectures with conductive elastic networks.展开更多
Surface-redox pseudocapacitive nanomaterials show promise for fast-charging energy storage.However,their high surface area usually leads to low density,which is not conducive to achieving both high volumetric capacity...Surface-redox pseudocapacitive nanomaterials show promise for fast-charging energy storage.However,their high surface area usually leads to low density,which is not conducive to achieving both high volumetric capacity and high-rate capability.Herein,we demonstrate that TiO_(2)nanosheets(meso-TiO_(2)-NSs)with densely packed mesoporous are capable of fast pseudocapacitance-dominated sodium-ion storage,as well as high volumetric and gravimetric capacities.Through compressing treatment,the compaction density of meso-TiO_(2)-NSs is up to~1.6g/cm^(2),combined with high surface area and high porosity with mesopore channels for rapid Na+diffusion.The compacted meso-TiO_(2)-NSs electrodes achieve high pseudocapacitance(93.6%of total charge at 1mV/s),high-rate capability(up to 10 A/g),and long-term cycling stability(10,000 cycles).More importantly,the space-efficiently packed structure enables high volumetric capacity.The thick-film meso-TiO_(2)-NSs anode with the mass loading of 10mg/cm^(2)delivers a gravimetric capacity of 165 mAh/g and a volumetric capacity of 223 mAh/cm^(3)at 5 mA/cm^(2),much higher than those of commercial hard carbon anode(80mAh/g and 86mAh/cm^(3)).This work highlights a pathway for designing a dense nanostructure that enables fast charge kinetics for high-density sodium-ion storage.展开更多
Bi is a promising candidate for energy storage materials because of its high volumetric capacity, stability in moisture/air, and facile preparation. In this study, the electrochemical performance of nanosized-Bi-embed...Bi is a promising candidate for energy storage materials because of its high volumetric capacity, stability in moisture/air, and facile preparation. In this study, the electrochemical performance of nanosized-Bi-embedded one-dimensional （1D） carbon nanofibers （Bi/C nanofibers） as anodes for Li-ion batteries （LIBs） and Na-ion batteries （NIBs） was systematically investigated. The Bi/C nanofibers were prepared using a single-nozzle electrospinning method with a specified Bi source followed by carbothermal reduction. Abundant Bi nanoparticles with diameters of approximately 20 nm were homogeneously dispersed and embedded in the 1D carbon nanofibers, as confirmed by structural and morphological characterization. Electrochemical measurements indicate that the Bi/C nanofiber anodes could deliver a long cycle life for LIBs and a preferable rate performance for NIBs. The superior electrochemical performances of the Bi/C nanofiber anodes are attributed to the 1D carbon nanofiber structure and uniform distribution of Bi nanoparticles embedded in the carbon matrix. This unique embedded structure provides a favorable electron carrier and buffering matrix for the effective release of mechanical stress caused by volume change and prevents the aggregation of Bi nanoparticles.展开更多
基金funded by the Science Foundation Ireland (SFI)under the Principal Investigator Program under contract No.11PI-1148,16/IA/4629 and SFI 16/M-ERA/3419funding under the European Union’s Horizon 2020 Research and Innovation Program+7 种基金grant agreement No.814464 (Si-DRIVE project)IRCLA/2017/285 and SFI Research Centres AMBER,Ma REI and CONFIRM 12/RC/2302_P2,12/RC/2278_P2,and 16/RC/3918SFI for SIRG grant No.18/SIRG/5484support from the Sustainable Energy Authority of Ireland through the Research Development and Demonstration Funding Program (Grant No.19/RDD/548)Enterprise Ireland through the Innovation Partnership Program (Grant No.IP 20190910)support from the SFI Research Centre Ma REI (award reference No.12/RC/2302_P2)support from the SFI Industry RD&I Fellowship Program (21/IRDIF/9876)the EU Horizon 2020 research and innovation program under the Marie Sklodowska-Curie Individual Fellowship Grant (843621)。
文摘Silicon nanowires(Si NWs)have been widely researched as the best alternative to graphite anodes for the next-generation of high-performance lithium-ion batteries(LIBs)owing to their high capacity and low discharge potential.However,growing binder-free Si NW anodes with adequate mass loading and stable capacity is severely limited by the low surface area of planar current collectors(CCs),and is particularly challenging to achieve on standard pure-Cu substrates due to the ubiquitous formation of Li+inactive silicide phases.Here,the growth of densely-interwoven In-seeded Si NWs is facilitated by a thin-film of copper-silicide(CS)network in situ grown on a Cu-foil,allowing for a thin active NW layer(<10μm thick)and high areal loading(≈1.04 mg/cm^(2))binder-free electrode architecture.The electrode exhibits an average Coulombic efficiency(CE)of>99.6%and stable performance for>900 cycles with≈88.7%capacity retention.More significantly,it delivers a volumetric capacity of≈1086.1 m A h/cm^(3)at 5C.The full-cell versus lithium manganese oxide(LMO)cathode delivers a capacity of≈1177.1 m A h/g at 1C with a stable rate capability.This electrode architecture represents significant advances toward the development of binder-free Si NW electrodes for LIB application.
基金financial support from the National Nature Science Foundation of China (21971146 and 22105118)the Nature Science Foundation of Shandong Provinces (ZR2021QB095)the China Postdoctoral Science Foundation (2020TQ0183 and 2021M701979)。
文摘Fast charging and high volumetric capacity are two of the critical demands for sodium-ion batteries(SIBs).Although nanostructured materials achieve outstanding rate performance,they suffer from low tap density and small volumetric capacity.Therefore,how to realize large volumetric capacity and high tap density simultaneously is very challenging.Here,N/F co-doped TiO_(2)/carbon microspheres(NF- TiO_(2)/C)are synthesized to achieve both of them.Theoretical calculations reveal that N and F co-doping increases the contents of oxygen vacancies and narrows the bandgaps of TiO_(2) and C,improving the electronic conductivity of NF- TiO_(2)/C.Furthermore,NF- TiO_(2)/C exhibits the high binding energy and low diffusion energy barrier of Na+,significantly facilitating Na+storage and Na+diffusion.Therefore,NF- TiO_(2)/C offers a high tap density(1.51 g cm^(-3)),an outstanding rate performance(125.9 mAh g^(-1) at 100 C),a large volumetric capacity(190 mAh cm^(-3) at 100 C),a high areal capacity(4.8 mAh cm^(-2))and an ultra-long cycling performance(80.2%after 10,000 cycles at 10 C)simultaneously.In addition,NF- TiO_(2)/C||Na_(3)V_(2)(PO_(4))_(3) full cells achieve an ultrahigh power density of 25.2 kW kg^(-1).These results indicate the great promise of NF- TiO_(2)/C as a high-volumetric-capacity and high-power-density anode material of SIBs.
基金supported primarily by the National Natural Science Foundation of China(No.22109025)National Key Research and Development Program of China(No.2020YFA0710303)Natural Science Foundation of Fujian Province,China(No.2021J05121)。
文摘The development of lithium-metal batteries(LMBs)is seriously restricted by the out-of-control dendrites growth and infinite volume expansion.Herein,a pervasive organic-inorganic layer construction strategy is reported for the composite lithium metal anode with congener-derived organic-inorganic solid electrolyte interphase(SEI).In this strategy,the organic-inorganic Ag@polydopamine(Ag@PDA)layer is coated on the arbitrary substrates by a simple two-step method.The thin and stable congener-derived SEI is insitu formed with fewer inorganic components and more organic components during charging/discharging.The polydopamine with sufficient adhesion groups and lithiophilic Ag layer realize near-zero nucleation overpotential during lithium deposition.The low interface resistance and stable lithium deposition are achieved.Moreover,the practical areal and volumetric capacities of the composite anode with three-dimensional copper(3DCu)as the substrate are 10 mAh/cm^(2)and 1538 mAh/cm^3(vs.the mass of anode).The symmetrical cell shows very low polarization voltage(10 mV)and more than 2500 h cycles life at 1 mA/cm^(2)(1 mAh/cm^(2)).The LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)-based full cells show improved capacity retention(82%)after 100 cycles at 0.5 C.The modified lithiophilic anode with congener-derived interphase provides a promising strategy to realize the next-generation dendrite-free LMBs.
基金supported by the National Key Research and Development Program of China(Grant No.2019YFA0210600)the National Natural Science Foundation of China(Grant Nos.BC0500463,22071081,and 22461015)the Shanghai Pilot Program for Basic Research of Shanghai Jiao Tong University,China.
文摘Aqueous zinc-ion batteries(AZIBs)have emerged as promising candidates for next-generation energy storage systems due to their inherent safety,cost-effectiveness,and high theoretical capacity.However,their practical application remains constrained by limited cycling stability and sluggish ion diffusion kinetics,particularly under high mass loading conditions.These limitations are primarily attributed to the restricted ion transport pathways within the electrode structure and structural degradation caused by repeated zinc-ion insertion and extraction in highly loaded electrodes.To address these challenges,formamide(FA)-inserted VOPO_(4)(FA-VOPO_(4))nanosheet cathodes were designed with expanded interlayer spacing(9.3Å),where FA molecules partially replace interlayer water,thereby enhancing both structural stability and ion transport pathways.This unique structural modification,supported by synergistic hydrogen bonding between FA and residual water,significantly improves Zn2+diffusion kinetics and charge transfer properties,as confirmed by electrochemical tests and theoretical analysis.Consequently,FA-VOPO_(4)electrodes delivered a remarkable volumetric capacity of 733 mAh/cm^(3)at 40 mA/g,approximately 8 times higher than that of the VOPO_(4)·2H_(2)O electrode,and retained 82.1%of their capacity after 1000 cycles at 1 A/g with a mass loading of 10 mg/cm^(2).Even at a high mass loading of 20 mg/cm^(2)(4.4 mAh/cm^(2)),the FA-VOPO_(4)cathode maintained a volumetric capacity of 535 mAh/cm^(3).These findings provide valuable insights into electrode design strategies for high-performance AZIBs,contributing to the development of safer,more efficient energy storage technologies with potential applications in grid storage and portable electronics.
基金National Natural Science Foundation of China(Grant Nos.52302249 and 12304003)Shenzhen Science and Technology Innovation Program(Grant No.KCXFZ20201221173010027).
文摘To meet the growing demand for high-energy-density lithium-ion batteries(LIBs),silicon(Si)anodes have gained attention as a promising material for next-generation anodes owing to their ultrahigh gravimetric capacity.Nevertheless,the Si anode faces significant challenges,particularly severe volume expansion during cycling,which leads to rapid capacity degradation and greatly hinders its commercialization potential.Although extensive research has focused on mitigating volume changes and constructing stable solid-electrolyte interphases on Si-based anodes,a crucial factor for practical application,namely the volumetric capacity,has been often overlooked.For Si-based anodes to replace conventional graphite anodes,their volumetric capacity must be thoroughly evaluated.Key factors determining the volumetric capacity include gravimetric capacity,active material mass ratio,initial Coulombic efficiency,electrode swelling ratio,and the negative-to-positive capacity ratio.This paper systematically analyzes,discusses,and summarizes each of these factors in detail.Common issues with existing strategies are identified,and future research directions concerning the commercialization of Si-based anodes are outlined.This study provides a systematic and novel perspective on effectively modifying and designing Si-based anodes,aiming to promote the volumetric capacity toward the large-scale industrialization of next-generation LIBs.
基金supported by the New Energy Project for Electric Vehicles in National Key Research and Development Program (2016YFB0100200)the National Natural Science Foundation of China (21573114 and 51502145)
文摘Low volumetric energy density is a bottleneck for the application of lithium-sulfur (Li-S)battery.The low- density sulfur cooperated with the light-weight carbon sub- strate realizes electrochemical cycle stability,but leads to worse volumetric energy density.Here,nickel ferrite (NiFe2O4)nanofibers as novel substrate for sulfur not only anchor lithium polysulfides to enhance the cycle stability of sulfur cathode,but also contribute to the high volumetric capacity of the S/nickel ferrite composite.Specifically,the S/ nickel ferrite composite presents an initial volumetric capacity of 1,281.7mA h cm^-3-composite at 0.1C rate,1.9times higher than that of S/carbon nanotubes,due to the high tap density of the S/nickel ferrite composite.
基金the National Natural Science Foundation of China (Nos. 21771180, 21971239)Natural Science Foundation of Fujian Province (No. 2020J06032)。
文摘Exploring high-capacity electrode materials is critical for the development of K-ion batteries.In this work,we report a layered-structured tungsten selenide(WSe2)anode,which not only delivers an ultrahigh volumetric capacity of 1772.8 Ah/L(or 188.4 mAh/g)at a current density of 5 mA/g but also exhibits good rate capability(72 mAh/g at 200 mA/g)and cycling stability(83.14%capacity retention over 100 cycles at 100 mA/g).We have also revealed the underlying reaction mechanism through ex situ X-ray powder diffraction.Furthermore,proof-of-concept full-cell batteries comprising of WSe2 anodes and Prussian Blue cathodes are capable of delivering an energy density of 135.2 Wh/kgcathode+anode.This work highlights the potential of WSe2 as a promising high-volumetric-capacity anode material for rechargeable potassium-ion batteries.
文摘The use of air conditioning and refrigeration systems improved the standard of living. However, the system contributes to global warming by releasing potential global warming refrigerants directly and powering the system. There is an obligation, like UN Kyoto Protocol, EU MAC Directive and Japan METI Directive to find an alternative low-GWP refrigerant with excellent thermophysical properties. In this paper, the global warming effect of an air-conditioning system is analyzed theoretically using few low-GWP refrigerant mixtures. New refrigerant mixtures are formed based on low GWP, high volumetric capacity, and refrigerating effect. After analyzing, refrigerant blends of R1234yf/R32 (40/60, 50/50, and 60/40 by wt%) and R1234ze/R32 (40/60, 50/50, and 60/40 by wt%) are found promising to replace the widely used R410A. The best performance of the refrigerant blend is found for R1234yf/R32 (40/60). These analyses are crucial for selecting suitable refrigerants for domestic air conditioning systems.
基金supported by the Beijing Natural Science Foundation,China(Grant No.L233011)the Open Project Program of State Key Laboratory of Virtual Reality Technology and Systems,Beihang University,China(No.VRLAB2025C11).
文摘Hydrogen storage is a critical component in transition to clean energy systems and the promotion of sustainable practices across various industries.The primary technical challenge lies in designing adsorbent materials that effectively balance both volumetric and gravimetric storage capabilities while ensuring operational reliability.Achieving this balance is essential for the efficient and practical application of hydrogen in fuel-based systems.Recently,in Nature Chemistry,Stoddart et al.introduced a straightforward and precise method:multivalent hydrogen bonding facilitates molecular linkage at defined nodal points in hydrogen-bonded organic frameworks(HOFs).This methodology demonstrates simultaneous optimization of hydrogen storage performance,achieving notable volumetric(53.7 g/L)and gravimetric(9.3 wt%)capacities under dynamic thermo-pressure cycling conditions.
文摘The silicon oxide nano-powders (SiO<sub>x</sub>-NPs) were obtained in an atmospheric microwave plasma torch using a gas-phase silicon tetrachloride (SiCl<sub>4</sub>) with N<sub>2</sub> and H<sub>2</sub>. The gas-phase SiCl<sub>4</sub> was injected with H<sub>2</sub> gas into the microwave plasma torch generated by N<sub>2</sub> and air swirl gas, and then the dark brown powders were deposited on the inner wall of a quartz tube. The sample was analyzed by an X-ray photoelectron spectroscopy (XPS), a scanning electron microscope (SEM), an energy dispersive spectrometer (EDS), and an X-ray diffraction (XRD). The average size and oxidation x values of synthesized SiO<sub>x</sub>-NPs were approximately 230 nm and 0.91, respectively. Furthermore, the volumetric charge capacity is 1127 mAh/g and has 89.2% retention after 100 cycles.
基金supported by the National Natural Science Foundation of China (Nos.51972066,52122211,52072323)the Natural Science Foundation of Guangdong Province of China (No.2021A1515011718)+1 种基金the Guangdong Province Universities and Colleges Pearl River Scholar Funded Scheme (2017)Nanqiang Young Top-notch Talent Fellowship in Xiamen University.
文摘Ultra-thick,dense alloy-type anodes are promising for achieving large areal and volumetric performance in potassium-ion batteries(PIBs),but severe volume expansion as well as sluggish ion and electron diffusion kinetics heavily impede their widespread application.Herein,we design highly dense(3.1 g cm^(-3))Ti_(3)C_(2)T_(x) MXene and graphene dual-encapsulated nano-Sb monolith architectures(HD-Sb@Ti_(3)C_(2)T_(x)-G)with high-conductivity elastic networks(1560 S m^(-1))and compact dually encapsulated structures,which exhibit a large volumetric capacity of 1780.2 mAh cm^(-3)(gravimetric capacity:565.0 mAh g^(-1)),a long-term stable lifespan of 500 cycles with 82%retention,and a large areal capacity of 8.6 mAh cm^(-2)(loading:31 mg cm^(-2))in PIBs.Using ex-situ SEM,in-situ TEM,kinetic investigations,and theoretical calculations,we reveal that the excellent areal and volumetric performance mechanism stems from the three dimensional(3D)high-conductivity elastic networks and the dualencapsulated Sb architecture of Ti_(3)C_(2)T_(x) and graphene;these effectively mitigate against volume expansion and the pulverization of Sb,offering good electrolyte penetration and rapid ionic/electronic transmission.Ti_(3)C_(2)T_(x) also decreases the Kþdiffusion energy barrier,and the ultra-thick compact electrode ensures volumetric and areal performance.These findings provide a feasible strategy for fabricating ultra-thick,dense alloy-type electrodes to achieve high areal and volumetric capacity energy storage via highly-dense,dual-encapsulated architectures with conductive elastic networks.
基金support from the National Natural Science Foundation of China(Nos.22005256,22179-113),the Natural Science Foundation of Fujian Province of China(No.2020J01034)Fundamental Research Funds for the Central Universities(Nos.20720210045,2072-0210084)+4 种基金Science and Technology Projects of Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM)(No.HRTP-2022-19)Kun Lan acknowledges the support from the National Natural Science Foundation of China(No.22205118)the“Junma"Program of Inner Mongolia University(No.21300-5223715)the Grassland Talent Program of Inner Mongolia Autonomous Region of China.Haobin Wu acknowledges the support the Zhejiang Provincial Natural Science Foundation(No.LR21E020003)the National Natural Science Foundation of China(No.22005266).
文摘Surface-redox pseudocapacitive nanomaterials show promise for fast-charging energy storage.However,their high surface area usually leads to low density,which is not conducive to achieving both high volumetric capacity and high-rate capability.Herein,we demonstrate that TiO_(2)nanosheets(meso-TiO_(2)-NSs)with densely packed mesoporous are capable of fast pseudocapacitance-dominated sodium-ion storage,as well as high volumetric and gravimetric capacities.Through compressing treatment,the compaction density of meso-TiO_(2)-NSs is up to~1.6g/cm^(2),combined with high surface area and high porosity with mesopore channels for rapid Na+diffusion.The compacted meso-TiO_(2)-NSs electrodes achieve high pseudocapacitance(93.6%of total charge at 1mV/s),high-rate capability(up to 10 A/g),and long-term cycling stability(10,000 cycles).More importantly,the space-efficiently packed structure enables high volumetric capacity.The thick-film meso-TiO_(2)-NSs anode with the mass loading of 10mg/cm^(2)delivers a gravimetric capacity of 165 mAh/g and a volumetric capacity of 223 mAh/cm^(3)at 5 mA/cm^(2),much higher than those of commercial hard carbon anode(80mAh/g and 86mAh/cm^(3)).This work highlights a pathway for designing a dense nanostructure that enables fast charge kinetics for high-density sodium-ion storage.
文摘Bi is a promising candidate for energy storage materials because of its high volumetric capacity, stability in moisture/air, and facile preparation. In this study, the electrochemical performance of nanosized-Bi-embedded one-dimensional （1D） carbon nanofibers （Bi/C nanofibers） as anodes for Li-ion batteries （LIBs） and Na-ion batteries （NIBs） was systematically investigated. The Bi/C nanofibers were prepared using a single-nozzle electrospinning method with a specified Bi source followed by carbothermal reduction. Abundant Bi nanoparticles with diameters of approximately 20 nm were homogeneously dispersed and embedded in the 1D carbon nanofibers, as confirmed by structural and morphological characterization. Electrochemical measurements indicate that the Bi/C nanofiber anodes could deliver a long cycle life for LIBs and a preferable rate performance for NIBs. The superior electrochemical performances of the Bi/C nanofiber anodes are attributed to the 1D carbon nanofiber structure and uniform distribution of Bi nanoparticles embedded in the carbon matrix. This unique embedded structure provides a favorable electron carrier and buffering matrix for the effective release of mechanical stress caused by volume change and prevents the aggregation of Bi nanoparticles.
