Cathode materials that possess high output voltage,as well as those that can be mass-produced using facile techniques,are crucial for the advancement of aqueous zinc-ion battery(ZIBs)applications,Herein,we present for...Cathode materials that possess high output voltage,as well as those that can be mass-produced using facile techniques,are crucial for the advancement of aqueous zinc-ion battery(ZIBs)applications,Herein,we present for the first time a new porous K_(0.5)VOPO_(4)·1.5H_(2)O polyanionic cathode(P-KIVP)with high output voltage(above 1.2 V)that can be manufactured at room temperature using straightforward coprecipitation and etching techniques.The P-KVP cathode experiences anisotropic crystal plane expansion via a sequential solid-solution intercalation and phase co nversion pathway throughout the Zn^(2+)storage process,as confirmed by in-situ synchrotron X-ray diffraction and ex-situ X-ray photoelectron spectroscopy.Similar to other layered vanadium-based polyanionic materials,the P-KVP cathode experiences a progressive decline in voltage during the cycle,which is demonstrated to be caused by the irreversible conversion into amorphous VO_(x).By introducing a new electrolyte containing Zn(OTF)_(2) to a mixed triethyl phosphate and water solution,it is possible to impede this irreversible conversion and obtain a high output voltage and longer cycle life by forming a P-rich cathode electrolyte interface layer.As a proof-of-concept,the flexible fiber-shaped ZIBs based on modified electrolyte woven into a fabric watch band can power an electronic watch,highlighting the application potential of P-KVP cathode.展开更多
The rate performance and cycle stability of graphitized needle coke(GNC)as anode are still limited by the sluggish kinetics and volume expansion during the Li ions intercalation and de-intercalation process.Especially...The rate performance and cycle stability of graphitized needle coke(GNC)as anode are still limited by the sluggish kinetics and volume expansion during the Li ions intercalation and de-intercalation process.Especially,the output of energy density for lithium ion batteries(LIBs)is directly affected by the delithiation capacity below 0.5 V.Here,the mildly expanded graphitized needle coke(MEGNC)with the enlarged interlayer spacing from 0.346 to 0.352 nm is obtained by the two-step mild oxidation intercalation modification.The voltage plateau of MEGNC anode below 0.5 V is obviously broadened as compared to the initial GNC anode,contributing to the enhancement of Li storage below the low voltage plateau.Moreover,the coin full cell and pouch full cell configured with MEGNC anode exhibit much enhanced Li storage ability,energy density and better cycling stability than those full cells configured with GNC and commercial graphite anodes,demonstrating the practical application value of MEGNC.The superior anode behaviors of MEGNC including the increased effective capacity at low voltage and superior cyclic stability are mainly benefited from the enlarged interlayer spacing,which not only accelerates the Li ions diffusion rate,but also effectively alleviates the volume expansion and fragmentation during the Li ions intercalation process.In addition,the above result is further confirmed by the density functional theory simulation.This work provides an effective modification strategy for the NC-based graphite to enhance the delithiation capacity at a low voltage plateau,dedicated to improving the energy density and durability of LIBs.展开更多
To overcome the problem of tuning area faults influencing the normal operation of the ZPW-2000A track circuit,protector models are established to protect the track circuit from interference.First,the parameters of the...To overcome the problem of tuning area faults influencing the normal operation of the ZPW-2000A track circuit,protector models are established to protect the track circuit from interference.First,the parameters of the protector models are calculated according to the circuit resonance principle.Second,a four-terminal network model of the track circuit in a normal state is established according to transmission-line theory and the transmission equations are derived.Third,the rail voltage is simulated,and an experimental platform is built to verify the models.Finally,the transmission equations of the protectors are derived,and the variation of the rail voltage is analyzed.The results indicate that tuning area faults have significant influence on the rail voltage.However,the installation of protectors can effectively reduce the influence,and not bear on the normal operation and maintenance of the track circuit,which significantly improves the protection ability of the track circuit against tuning area faults.展开更多
Flexible rechargeable aqueous zinc-ion batteries(ZIBs)have attracted extensive attentions in the energy storage field due to their high safety,environmental friendliness,and outstanding electrochemical performance whi...Flexible rechargeable aqueous zinc-ion batteries(ZIBs)have attracted extensive attentions in the energy storage field due to their high safety,environmental friendliness,and outstanding electrochemical performance while the exploration of high-voltage aqueous ZIBs with excellent rate capability is still a great challenge for the further application them in flexible and wearable electronics.Herein,we fabricated a 2.4 V high-voltage flexible aqueous ZIB,being among the highest voltage reported in aqueous ZIBs.Moreover,it exhibits extremely flat charging/discharging voltage platforms and the dropout voltage is only 0.1 V,which is the smallest gap in all aqueous batteries to our best knowledge.Furthermore,the prepared ZIB performs high rate capability of 25 C and energy density of 120 Wh kg?1 and exhibits excellent safety under various destructive conditions including hammering,sewing,punching,and soaking.These extraordinary results indicate the great application potential of our high-voltage flexible aqueous ZIB in wearable electronics.展开更多
In recent years, demands for intense and stable beams of medium-mass metal (such as V, Cr, Fe and Ni) ions are increasing for various experiments at 320 kV high voltage multi-discipline platform for highly charged ion...In recent years, demands for intense and stable beams of medium-mass metal (such as V, Cr, Fe and Ni) ions are increasing for various experiments at 320 kV high voltage multi-discipline platform for highly charged ions. Among them, ion beams of iron are of most need.展开更多
基金financially supported by National Natural Science Foundation of China(No.52102270)the Natural Science Foundation of Shandong Province of China(ZR2021QE002)+1 种基金the support from the Institute startup grant from Qingdao Universitythe Shandong Center for Engineered Nonwovens(SCEN)。
文摘Cathode materials that possess high output voltage,as well as those that can be mass-produced using facile techniques,are crucial for the advancement of aqueous zinc-ion battery(ZIBs)applications,Herein,we present for the first time a new porous K_(0.5)VOPO_(4)·1.5H_(2)O polyanionic cathode(P-KIVP)with high output voltage(above 1.2 V)that can be manufactured at room temperature using straightforward coprecipitation and etching techniques.The P-KVP cathode experiences anisotropic crystal plane expansion via a sequential solid-solution intercalation and phase co nversion pathway throughout the Zn^(2+)storage process,as confirmed by in-situ synchrotron X-ray diffraction and ex-situ X-ray photoelectron spectroscopy.Similar to other layered vanadium-based polyanionic materials,the P-KVP cathode experiences a progressive decline in voltage during the cycle,which is demonstrated to be caused by the irreversible conversion into amorphous VO_(x).By introducing a new electrolyte containing Zn(OTF)_(2) to a mixed triethyl phosphate and water solution,it is possible to impede this irreversible conversion and obtain a high output voltage and longer cycle life by forming a P-rich cathode electrolyte interface layer.As a proof-of-concept,the flexible fiber-shaped ZIBs based on modified electrolyte woven into a fabric watch band can power an electronic watch,highlighting the application potential of P-KVP cathode.
基金supported by the National Natural Science Foundation of China(21776309,22122807 and 21706283)。
文摘The rate performance and cycle stability of graphitized needle coke(GNC)as anode are still limited by the sluggish kinetics and volume expansion during the Li ions intercalation and de-intercalation process.Especially,the output of energy density for lithium ion batteries(LIBs)is directly affected by the delithiation capacity below 0.5 V.Here,the mildly expanded graphitized needle coke(MEGNC)with the enlarged interlayer spacing from 0.346 to 0.352 nm is obtained by the two-step mild oxidation intercalation modification.The voltage plateau of MEGNC anode below 0.5 V is obviously broadened as compared to the initial GNC anode,contributing to the enhancement of Li storage below the low voltage plateau.Moreover,the coin full cell and pouch full cell configured with MEGNC anode exhibit much enhanced Li storage ability,energy density and better cycling stability than those full cells configured with GNC and commercial graphite anodes,demonstrating the practical application value of MEGNC.The superior anode behaviors of MEGNC including the increased effective capacity at low voltage and superior cyclic stability are mainly benefited from the enlarged interlayer spacing,which not only accelerates the Li ions diffusion rate,but also effectively alleviates the volume expansion and fragmentation during the Li ions intercalation process.In addition,the above result is further confirmed by the density functional theory simulation.This work provides an effective modification strategy for the NC-based graphite to enhance the delithiation capacity at a low voltage plateau,dedicated to improving the energy density and durability of LIBs.
基金Supported by the National Natural Science Foundation of China(61763023).
文摘To overcome the problem of tuning area faults influencing the normal operation of the ZPW-2000A track circuit,protector models are established to protect the track circuit from interference.First,the parameters of the protector models are calculated according to the circuit resonance principle.Second,a four-terminal network model of the track circuit in a normal state is established according to transmission-line theory and the transmission equations are derived.Third,the rail voltage is simulated,and an experimental platform is built to verify the models.Finally,the transmission equations of the protectors are derived,and the variation of the rail voltage is analyzed.The results indicate that tuning area faults have significant influence on the rail voltage.However,the installation of protectors can effectively reduce the influence,and not bear on the normal operation and maintenance of the track circuit,which significantly improves the protection ability of the track circuit against tuning area faults.
基金the National Natural Science Foundation of China(No.21805063)the Natural Science Foundation of Guangdong Province for Distinguished Young Scholars(No.2018B030306022)+1 种基金the Economic,Trade and Information Commission of Shenzhen Municipality through the Graphene Manufacture Innovation Center(No.201901161514)The authors also acknowledge the support from China Postdoctoral Science Foundation(2018M641823).
文摘Flexible rechargeable aqueous zinc-ion batteries(ZIBs)have attracted extensive attentions in the energy storage field due to their high safety,environmental friendliness,and outstanding electrochemical performance while the exploration of high-voltage aqueous ZIBs with excellent rate capability is still a great challenge for the further application them in flexible and wearable electronics.Herein,we fabricated a 2.4 V high-voltage flexible aqueous ZIB,being among the highest voltage reported in aqueous ZIBs.Moreover,it exhibits extremely flat charging/discharging voltage platforms and the dropout voltage is only 0.1 V,which is the smallest gap in all aqueous batteries to our best knowledge.Furthermore,the prepared ZIB performs high rate capability of 25 C and energy density of 120 Wh kg?1 and exhibits excellent safety under various destructive conditions including hammering,sewing,punching,and soaking.These extraordinary results indicate the great application potential of our high-voltage flexible aqueous ZIB in wearable electronics.
文摘In recent years, demands for intense and stable beams of medium-mass metal (such as V, Cr, Fe and Ni) ions are increasing for various experiments at 320 kV high voltage multi-discipline platform for highly charged ions. Among them, ion beams of iron are of most need.
