Solid oxide fuel cells(SOFCs)are regarded to be a key clean energy system to convert chemical energy(e.g.H_(2) and O_(2))into electrical energy with high efficiency,low carbon footprint,and fuel flexibility.The electr...Solid oxide fuel cells(SOFCs)are regarded to be a key clean energy system to convert chemical energy(e.g.H_(2) and O_(2))into electrical energy with high efficiency,low carbon footprint,and fuel flexibility.The electrolyte,typically doped zirconia,is the"state of the heart"of the fuel cell technologies,determining the performance and the operating temperature of the overall cells.Yttria stabilized zirconia(YSZ)have been widely used in SOFC due to its excellent oxide ion conductivity at high temperature.The composition and temperature dependence of the conductivity has been hotly studied in experiment and,more recently,by theoretical simulations.The characterization of the atomic structure for the mixed oxide system with different compositions is the key for elucidating the conductivity behavior,which,however,is of great challenge to both experiment and theory.This review presents recent theoretical progress on the structure and conductivity of YSZ electrolyte.We compare different theoretical methods and their results,outlining the merits and deficiencies of the methods.We highlight the recent results achieved by using stochastic surface walking global optimization with global neural network potential(SSW-NN)method,which appear to agree with available experimental data.The advent of machine-learning atomic simulation provides an affordable,efficient and accurate way to understand the complex material phenomena as encountered in solid electrolyte.The future research directions for design better electrolytes are also discussed.展开更多
In the current aera of rapid development in the field of electric vehicles and electrochemical energy storage,solid-state battery technology is attracting much research and attention.Solid-state electrolytes,as the ke...In the current aera of rapid development in the field of electric vehicles and electrochemical energy storage,solid-state battery technology is attracting much research and attention.Solid-state electrolytes,as the key component of next-generation battery technology,are favored for their high safety,high energy density,and long life.However,finding high-performance solid-state electrolytes is the primary challenge for solid-state battery applications.Focusing on inorganic solid-state electrolytes,this work highlights the need for ideal solid-state electrolytes to have low electronic conductivity,good thermal stability,and structural and phase stability.Traditional experimental and theoretical computational methods suffer from inefficiency,thus machine learning methods become a novel path to intelligently predict material properties by analyzing a large number of inorganic structural properties and characteristics.Through the gradient descent-based XGBoost algorithm,we successfully predicted the energy band structure and stability of the materials,and screened out only 194 ideal solid-state electrolyte structures from more than 6000 structures that satisfy the requirements of low electronic conductivity and stability simultaneously,which greatly accelerated the development of solid-state batteries.展开更多
Lithium-sulfur(Li-S) battery is a promising choice for the next generation of high-energy rechargeable batteries, but its application is impeded by the high dissolution of the polysulfides in commonly used organic ele...Lithium-sulfur(Li-S) battery is a promising choice for the next generation of high-energy rechargeable batteries, but its application is impeded by the high dissolution of the polysulfides in commonly used organic electrolyte. Room temperature ionic liquids(RTILs) have been considered as appealing candidates for the electrolytes in Li-S batteries. We investigated the effect of cations in RTILs on the electrochemical performance for Li-S batteries. Ex situ investigation of lithium anode for Li-S batteries indicates that during the discharge/charge process the RTIL with N-methyl-N-propylpyrrolidine cations(P13) can effectively suppress the dissolution of the polysulfides, whereas the RTIL with 1-methyl-3-propyl imidazolium cation(PMIM) barely alleviates the shuttling problem. With 0.5 mol L-1 LiTFSI/P13 TFSI as the electrolyte of Li-S battery, the ketjen black/ sulfur cathode material exhibits high capacity and remarkable cycling stability, which promise the application of the P13-based RTILs in Li-S batteries.展开更多
The development of high-performance solid polymer electrolytes is crucial for producing all-solid-state lithium metal batteries with high safety and high energy density.However,the low ionic conductivity of solid poly...The development of high-performance solid polymer electrolytes is crucial for producing all-solid-state lithium metal batteries with high safety and high energy density.However,the low ionic conductivity of solid polymer electrolytes and their unstable electrolyte/electrode interfaces have hindered their widespread utilization.To address these critical challenges,a strong Lewis acid(aluminum fluoride(AIF_(3)))with dual functionality is introduced into poly(ethylene oxide)(PEO)-based polymer electrolyte.The AlF;facilitates the dissociation of lithium salt,increasing the iontransfer efficiency due to the Lewis acid-base interaction;further the in-situ formation of lithium fluoride-rich interfacial layer is promoted,which suppresses the uneven lithium deposition and continuous undesired reactions between the Li metal and PEO matrix.Benefiting from our rational design,the symmetric Li/Li battery with the modified electrolyte exhibits much longer cycling stability(over 3600 h)than that of the pure PEO/lithium bis(trifluoromethanesulfonyl)imide(LiTFSI)electrolyte(550 h).Furthermore,the all-solid-state LiFeP04 full cell with the composite electrolyte displays a much higher Coulombic efficiency(98.4%after 150 cycles)than that of the electrolyte without the AlF;additive(63.3%after 150 cycles)at a large voltage window of 2.4-4.2 V,demonstrating the improved interface and cycling stability of solid polymer lithium metal batteries.展开更多
Aqueous zinc-ion batteries(ZIBs)are perceived as one of the most upcoming grid-scale storage systems.However,the issues of electrode dissolution,dendrite formation,and corrosion in traditional liquid electrolytes have...Aqueous zinc-ion batteries(ZIBs)are perceived as one of the most upcoming grid-scale storage systems.However,the issues of electrode dissolution,dendrite formation,and corrosion in traditional liquid electrolytes have plagued its progress.In this work,Zn dendrite growth and side reactions are effectively suppressed by a highly-confined tannic acid(TA)modified sodium alginate(SA)composite gel electrolyte(TA-SA).The ion-confinement effect is enhanced by divalent zinc ions coordinated with carboxyl groups and chelated with phenolic hydroxyl groups,thus guiding and regulating Zn deposition to achieve steady zinc plating/stripping behavior.As a consequence,the Zn/TA-SA/NH_(4)V_(4)O_(10) full cells deliver a high specific capacity of 238.6 mAh g^(-1) and maintain 94.51%over 900 cycles at 2 A g^(-1).Notably,after resting over 5 d,the capacity can be stabilized with a capacity retention of 97.25%after 200 cycles at 2 A g^(-1).This highlyconfined and hydrogen bond-strengthened gel electrolyte may provide an effective strategy for the future development of quasi-solid-state metal batteries.展开更多
Developing electrolyte with high electrochemical stability is the most effective way to improve the energy density of double layer capacitors(DLCs), and ionic liquid is a promising choice. Herein, a novel ionic liquid...Developing electrolyte with high electrochemical stability is the most effective way to improve the energy density of double layer capacitors(DLCs), and ionic liquid is a promising choice. Herein, a novel ionic liquid based high potential electrolyte with a stabilizer, succinonitrile, was proposed to improve the high potential stability of the DLC. The electrolyte with 7.5 wt% succinonitrile added has a high ionic conductivity of 41.1 m S cm^(-1) under ambient temperature, and the DLC adopting this electrolyte could be charged to 3.0 V with stable cycle ability even under a discharge current density of 6 A g^(-1). Moreover, the energy density could be increased by 23.4% when the DLC was charged to 3.0 V compared to that charged to 2.7 V.展开更多
Interconnected microspheres of V2Os composed of ultra-long nanobelts are synthesized in an environmental friendly way by adopting a conventional anodization process combined with annealing. The synthesis process is si...Interconnected microspheres of V2Os composed of ultra-long nanobelts are synthesized in an environmental friendly way by adopting a conventional anodization process combined with annealing. The synthesis process is simple and low-cost because it does not require any additional chemicals or reagents. Commercial fish-water is used as an electrolyte medium to anodize vanadium foil for the first time. Electron microscopy investigation reveals that each belt consists of numerous nanofibers with free space between them. Therefore, this novel nanostructure demonstrates many outstanding features during electrochemical operation. This structure prevents self-aggregation of active materials and fully utilizes the advantage of active materials by maintaining a large effective contact area between active materials, conductive additives, and electrolyte, which is a key challenge for most nanomaterials. The electrodes exhibit promising electrochemical performance with a stable discharge capacity of 227 mAh·g^-1 at 1C after 200 cycles. The rate capability of the electrode is outstanding, and the obtained capacity is as high as 278 at 0.5C, 259 at 1C, 240 at 2C, 206 at 5C, and 166 mAh·g^-1 at 10C. Overall this novel structure could be one of the most favorable nanostructures of vanadium oxide-based cathodes for Li-ion batteries.展开更多
基金supported by Shanghai Sailing Program(No.19YF1442800)the National Key Research and Development Program of China(No.2018YFA0208600)the National Natural Science Foundation of China(No.22003040,No.22033003,No.91945301,No.91745201,and No.21533001).
文摘Solid oxide fuel cells(SOFCs)are regarded to be a key clean energy system to convert chemical energy(e.g.H_(2) and O_(2))into electrical energy with high efficiency,low carbon footprint,and fuel flexibility.The electrolyte,typically doped zirconia,is the"state of the heart"of the fuel cell technologies,determining the performance and the operating temperature of the overall cells.Yttria stabilized zirconia(YSZ)have been widely used in SOFC due to its excellent oxide ion conductivity at high temperature.The composition and temperature dependence of the conductivity has been hotly studied in experiment and,more recently,by theoretical simulations.The characterization of the atomic structure for the mixed oxide system with different compositions is the key for elucidating the conductivity behavior,which,however,is of great challenge to both experiment and theory.This review presents recent theoretical progress on the structure and conductivity of YSZ electrolyte.We compare different theoretical methods and their results,outlining the merits and deficiencies of the methods.We highlight the recent results achieved by using stochastic surface walking global optimization with global neural network potential(SSW-NN)method,which appear to agree with available experimental data.The advent of machine-learning atomic simulation provides an affordable,efficient and accurate way to understand the complex material phenomena as encountered in solid electrolyte.The future research directions for design better electrolytes are also discussed.
基金supported by the National Natural Science Foundation of China(No.21421063,No.21473166,No.21573211,No.21633007,No.21790350,No.21803067,No.91950207)the Chinese Academy of Sciences(QYZDB-SSW-SLH018)+3 种基金the Anhui Initiative in Quantum Information Technologies(AHY090200)the USTC-NSRL Joint Funds(UN2018LHJJ)the Anhui Provincial Natural Science Foundation(2108085QB63)Numerical Theoretical simulations were done in the Supercomputing Center of USTC.
文摘In the current aera of rapid development in the field of electric vehicles and electrochemical energy storage,solid-state battery technology is attracting much research and attention.Solid-state electrolytes,as the key component of next-generation battery technology,are favored for their high safety,high energy density,and long life.However,finding high-performance solid-state electrolytes is the primary challenge for solid-state battery applications.Focusing on inorganic solid-state electrolytes,this work highlights the need for ideal solid-state electrolytes to have low electronic conductivity,good thermal stability,and structural and phase stability.Traditional experimental and theoretical computational methods suffer from inefficiency,thus machine learning methods become a novel path to intelligently predict material properties by analyzing a large number of inorganic structural properties and characteristics.Through the gradient descent-based XGBoost algorithm,we successfully predicted the energy band structure and stability of the materials,and screened out only 194 ideal solid-state electrolyte structures from more than 6000 structures that satisfy the requirements of low electronic conductivity and stability simultaneously,which greatly accelerated the development of solid-state batteries.
基金supported by the"Strategic Priority Research Program"of the Chinese Academy of Sciences(XDA09010300)the National Natural Science Foundation of China(51225204,91127044,U1301244,21121063)+1 种基金the National Basic Research Program of China(2011CB935700,2012CB932900)the Chinese Academy of Sciences
文摘Lithium-sulfur(Li-S) battery is a promising choice for the next generation of high-energy rechargeable batteries, but its application is impeded by the high dissolution of the polysulfides in commonly used organic electrolyte. Room temperature ionic liquids(RTILs) have been considered as appealing candidates for the electrolytes in Li-S batteries. We investigated the effect of cations in RTILs on the electrochemical performance for Li-S batteries. Ex situ investigation of lithium anode for Li-S batteries indicates that during the discharge/charge process the RTIL with N-methyl-N-propylpyrrolidine cations(P13) can effectively suppress the dissolution of the polysulfides, whereas the RTIL with 1-methyl-3-propyl imidazolium cation(PMIM) barely alleviates the shuttling problem. With 0.5 mol L-1 LiTFSI/P13 TFSI as the electrolyte of Li-S battery, the ketjen black/ sulfur cathode material exhibits high capacity and remarkable cycling stability, which promise the application of the P13-based RTILs in Li-S batteries.
基金supported by the research fund of Shenzhen Science and Technology Innovation Committee(SGDX20201103093600003)the University of Macao,Macao SAR(MYRG2018-00079-IAPME and MYRG2019-00115-IAPME)+2 种基金the Science and Technology Development Fund,Macao SAR(0092/2019/A2,0059/2018/A2,and 009/2017/AMJ)the National Thousand Young Talent planthe National Natural Science Foundation of China(21875040&21905051)。
文摘The development of high-performance solid polymer electrolytes is crucial for producing all-solid-state lithium metal batteries with high safety and high energy density.However,the low ionic conductivity of solid polymer electrolytes and their unstable electrolyte/electrode interfaces have hindered their widespread utilization.To address these critical challenges,a strong Lewis acid(aluminum fluoride(AIF_(3)))with dual functionality is introduced into poly(ethylene oxide)(PEO)-based polymer electrolyte.The AlF;facilitates the dissociation of lithium salt,increasing the iontransfer efficiency due to the Lewis acid-base interaction;further the in-situ formation of lithium fluoride-rich interfacial layer is promoted,which suppresses the uneven lithium deposition and continuous undesired reactions between the Li metal and PEO matrix.Benefiting from our rational design,the symmetric Li/Li battery with the modified electrolyte exhibits much longer cycling stability(over 3600 h)than that of the pure PEO/lithium bis(trifluoromethanesulfonyl)imide(LiTFSI)electrolyte(550 h).Furthermore,the all-solid-state LiFeP04 full cell with the composite electrolyte displays a much higher Coulombic efficiency(98.4%after 150 cycles)than that of the electrolyte without the AlF;additive(63.3%after 150 cycles)at a large voltage window of 2.4-4.2 V,demonstrating the improved interface and cycling stability of solid polymer lithium metal batteries.
基金supported by the National Natural Science Foundation of China(51972346,51932011)the Hunan Natural Science Fund for Distinguished Young Scholar(2021JJ10064)+1 种基金the Program of Youth Talent Support for Hunan Province(2020RC3011)the Innovation-Driven Project of Centra South University(2020CX024)。
文摘Aqueous zinc-ion batteries(ZIBs)are perceived as one of the most upcoming grid-scale storage systems.However,the issues of electrode dissolution,dendrite formation,and corrosion in traditional liquid electrolytes have plagued its progress.In this work,Zn dendrite growth and side reactions are effectively suppressed by a highly-confined tannic acid(TA)modified sodium alginate(SA)composite gel electrolyte(TA-SA).The ion-confinement effect is enhanced by divalent zinc ions coordinated with carboxyl groups and chelated with phenolic hydroxyl groups,thus guiding and regulating Zn deposition to achieve steady zinc plating/stripping behavior.As a consequence,the Zn/TA-SA/NH_(4)V_(4)O_(10) full cells deliver a high specific capacity of 238.6 mAh g^(-1) and maintain 94.51%over 900 cycles at 2 A g^(-1).Notably,after resting over 5 d,the capacity can be stabilized with a capacity retention of 97.25%after 200 cycles at 2 A g^(-1).This highlyconfined and hydrogen bond-strengthened gel electrolyte may provide an effective strategy for the future development of quasi-solid-state metal batteries.
基金supported by the International S&T Cooperation Program of China (2014DFA61670)the Key Program of National Natural Science Foundation of China (91434203)+1 种基金the International Cooperation and Exchange of the National Natural Science Foundation of China (51561145020)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA09010103)
文摘Developing electrolyte with high electrochemical stability is the most effective way to improve the energy density of double layer capacitors(DLCs), and ionic liquid is a promising choice. Herein, a novel ionic liquid based high potential electrolyte with a stabilizer, succinonitrile, was proposed to improve the high potential stability of the DLC. The electrolyte with 7.5 wt% succinonitrile added has a high ionic conductivity of 41.1 m S cm^(-1) under ambient temperature, and the DLC adopting this electrolyte could be charged to 3.0 V with stable cycle ability even under a discharge current density of 6 A g^(-1). Moreover, the energy density could be increased by 23.4% when the DLC was charged to 3.0 V compared to that charged to 2.7 V.
文摘Interconnected microspheres of V2Os composed of ultra-long nanobelts are synthesized in an environmental friendly way by adopting a conventional anodization process combined with annealing. The synthesis process is simple and low-cost because it does not require any additional chemicals or reagents. Commercial fish-water is used as an electrolyte medium to anodize vanadium foil for the first time. Electron microscopy investigation reveals that each belt consists of numerous nanofibers with free space between them. Therefore, this novel nanostructure demonstrates many outstanding features during electrochemical operation. This structure prevents self-aggregation of active materials and fully utilizes the advantage of active materials by maintaining a large effective contact area between active materials, conductive additives, and electrolyte, which is a key challenge for most nanomaterials. The electrodes exhibit promising electrochemical performance with a stable discharge capacity of 227 mAh·g^-1 at 1C after 200 cycles. The rate capability of the electrode is outstanding, and the obtained capacity is as high as 278 at 0.5C, 259 at 1C, 240 at 2C, 206 at 5C, and 166 mAh·g^-1 at 10C. Overall this novel structure could be one of the most favorable nanostructures of vanadium oxide-based cathodes for Li-ion batteries.
