Developing advanced secondary batteries with low cost and high safety has attracted increasing research interests across the world.In particular,the aqueous zinc-ion battery(AZIB)has been regarded as a promising candi...Developing advanced secondary batteries with low cost and high safety has attracted increasing research interests across the world.In particular,the aqueous zinc-ion battery(AZIB)has been regarded as a promising candidate owing to the high abundance and capacity of Zn metal.Currently,manganese-based and vanadium-based oxides are most common choices for cathode materials used in AZIBs,but they unfortunately show a moderate cell voltage and limited rate performance induced by slow intercalation-extraction kinetics of Zn^(2+)ions.To address these issues,alternative cathode systems with tunable redox potentials and intrinsic fast kinetics have been exploited.In the past few years,conversion-type cathodes of I_(2)and S have become the most illustrative examples to match or even surpass the performance of conventional metal oxide cathodes in AZIBs.Herein,we sum up most recent progress in conversion-type cathodes and focus on novel ideas and concepts in designing/modifying cathodes for AZIBs with high voltage/capacity.Additionally,potential directions and future efforts are tentatively proposed for further development of conversion-type cathodes,aiming to speed up the practical application of AZIBs.展开更多
Solid-state lithium batteries(SSLBs)are regarded as an essential growth path in energy storage systems due to their excellent safety and high energy density.In particular,SSLBs using conversion-type cathode materials ...Solid-state lithium batteries(SSLBs)are regarded as an essential growth path in energy storage systems due to their excellent safety and high energy density.In particular,SSLBs using conversion-type cathode materials have received widespread attention because of their high theoretical energy densities,low cost,and sustainability.Despite the great progress in research and development of SSLBs based on conversiontype cathodes,their practical applications still face challenges such as blocked ionic-electronic migration pathways,huge volume change,interfacial incompatibility,and expensive processing costs.This review focuses on the advantages and critical issues of coupling conversion-type cathodes with solid-state electrolytes(SSEs),as well as state-of-the-art progress in various promising cathodes(e.g.,FeS_(2),CuS,FeF_(3),FeF_(2),and S)in SSLBs.Furthermore,representative research on conversion-type solid-state full cells is discussed to offer enlightenment for their practical application.Significantly,the energy density exhibited by the S cathode stands out impressively,while sulfide SSEs and halide SSEs have demonstrated immense potential for coupling with conversion-type cathodes.Finally,perspectives on conversion-type cathodes are provided at the material,interface,composite electrode,and battery levels,with a view to accelerating the development of conversion-type cathodes for high-energy–density SSLBs.展开更多
Conversion-type anode materials are highly desirable for Na-ion batteries(NIBs)due to their high theoretical capacity.Nevertheless,the active materials undergo severe expansion and pulverization during the sodiation,r...Conversion-type anode materials are highly desirable for Na-ion batteries(NIBs)due to their high theoretical capacity.Nevertheless,the active materials undergo severe expansion and pulverization during the sodiation,resulting in inferior cycling stability.Herein,a self-supporting three-dimensional(3D)graphene sponge decorated with Fe_(2)O_(3)nanocubes(rGO@Fe_(2)O_(3))is constructed.Specifically,the 3D graphene sponge with resilience and high porosity benefits to accommodate the volume expansion of the Fe_(2)O_(3)nanocubes and facilitates the rapid electrons/ions transport,enabling spatial confinement to achieve outstanding results.Besides,the free-standing rGO@Fe_(2)O_(3)can be directly used as an electrode without additional binders and conductive additives,which helps to obtain a higher energy density.Based on the total mass of the rGO@Fe_(2)O_(3)material,the rGO@Fe_(2)O_(3)anode presents a specific capacity of 859 mAh/g at 0.1 A/g.It also delivers an impressive cycling performance(327 mAh/g after 2000 cycles at 1 A/g)and a superior rate capacity(162mAh/g at 20 A/g).The coin-type Na_(3)V_(2)(PO_(4))_(3)@C//rGO@Fe_(2)O_(3)NIB exhibits an energy density of 265.3Wh/kg.This unique 3D ionic/electronic conductive network may provide new strategies to design advanced conversion-type anode materials for high-performance NIBs.展开更多
δ-MnO_(2)has received constantly growing attention due to its stable tunnel-type crystalline structures for Zn^(2+)or Zn^(2+)/H^(+)intercalation,however,only partial Mn active sites exhibit electrochemical reactions,...δ-MnO_(2)has received constantly growing attention due to its stable tunnel-type crystalline structures for Zn^(2+)or Zn^(2+)/H^(+)intercalation,however,only partial Mn active sites exhibit electrochemical reactions,and most Mn atoms would stay the same to maintain the structure frame,indicative of low capacity and long cycling life theoretically.By comparison,for Cu-based conversion-typed materials,all Cu sites can perform electrochemical reactions if fully utilized,resulting in high rate capacity,however,short cycling life due to fracture,and even pulverization induced by volume changes during cycling.In this work,a hybrid cathode with intercalation and conversion behaviors is devised,in which intertwinedδ-MnO_(2)nanosheets shell wrap conversion-typed Cu_(2)O core firmly for stable conversion reaction during cycling.As a result,the optimized Cu_(2)O/MnO_(2)(denoted as MCO)cathode demonstrates the hybrid properties of long cycling life and high rate capacity,inheriting fromδ-MnO_(2)and Cu_(2)O,respectively.MCO cathodes with carbon cloth current collectors in full batteries deliver reversible capacities of 291.9 mA h g^(−1)at 1 A g^(−1),and retain 95%capacity at 20.0 A g^(−1)after 4300 cycles.Additionally,the energy density of 513.94 Wh kg^(−1)and power density of 7.2 kW kg^(−1)based on the MCO mass are exhibited,verifying its practical application.This work demonstrates the combination of intercalation and conversion in one electrochemical system and may provide new perspectives for the optimizing application of hybrid mechanisms.展开更多
Potassium-ion batteries(KIBs)have become the most promising alternative to lithium-ion batteries for large-scale energy storage system due to their abundance and low cost.However,previous reports focused on the interc...Potassium-ion batteries(KIBs)have become the most promising alternative to lithium-ion batteries for large-scale energy storage system due to their abundance and low cost.However,previous reports focused on the intercalation-type cathode materials usually showed an inferior capacity,together with a poor cyclic life caused by the repetitive intercalation of large-size K-ions,which hinders their practical application.Here,we combine the strategies of carbon coating,template etching and hydrothermal selenization to prepare yolk-shelled FeSe_(2)@N-doped carbon nanoboxes(FeSe_(2)@C NBs),where the inner highly-crystalline FeSe_(2)clusters are completely surrounded by the self-supported carbon shell.The integrated and highly conductive carbon shell not only provides a fast electron/ion diffusion channel,but also prevents the agglomeration of FeSe_(2)clusters.When evaluated as a conversion-type cathode material for KIBs,the FeSe_(2)@C NBs electrode delivers a relatively high specific capacity of 257 mAh/g at 100 mA/g and potential platform of about 1.6 V,which endow a high energy density of about 411 Wh/kg.Most importantly,by designing a robust host with large internal void space to accommodate the volumetric variation of the inner FeSe_(2)clusters,the battery based on FeSe_(2)@C NBs exhibits ultra-long cycle stability.Specifically,even after 700 cycles at 100 mA/g,a capacity of 221 mAh/g along with an average fading rate of only 0.02%can be retained,which achieves the optimal balance of high specific capacity and long-cycle stability.展开更多
Due to the high theoretical capacity and energy density,conversion-type metal fluorides have captured plenty of attentions but still suffer from the inferior kinetic behaviors and serious capacity fading.For addressin...Due to the high theoretical capacity and energy density,conversion-type metal fluorides have captured plenty of attentions but still suffer from the inferior kinetic behaviors and serious capacity fading.For addressing the issues above,the strategies of surface/interface engineering are utilized for the preparation of sphere-like porous FeF3@C materials,where the as-resulted sample displays the uniform particle size(~150 nm in radii)and the ultrathin carbon layers(thickness of~10 nm).Significantly,benefitting from the rich oxygen of precursor,the interfacial chemical bonds Fe-O-C are successfully constructed between carbon matrix and FeF3 materials,accompanying by the enhancements of ions/electrons(e-)conductivity and stability.When used as Li-storage cathodes,the initial lithium-ions storage capacity could reach up to~400mAh·g^(-1) at 0.1 A·g^(-1).Even at 1.0 A·g^(-1),the capacity could be still remained at about 210 mAh·g^(-1),with the retention of 85%after 400 cycles.Assisted by the detailed kinetic behaviors,the considerable electrochemical properties come from the enhanced diffusion-controlled contributions,whilst the segregation of Fe with LiF is effectively alleviated by unique architecture.Moreover,during cycling,solid electrolyte interface film is reversibly formed/decomposed.Thus,this work is expected to offer rational exterior/interfacial designing strategies for metalbased samples.展开更多
Doping have been considered as a prominent strategy to stabilize crystal structure of battery materials during the insertion and removal of alkali ions.The instructive knowledge and experience acquired from doping str...Doping have been considered as a prominent strategy to stabilize crystal structure of battery materials during the insertion and removal of alkali ions.The instructive knowledge and experience acquired from doping strategies predominate in cathode materials,but doping principle in anodes remains unclear.Here,we demonstrate that trace element doping enables stable conversion-reaction and ensures structural integrity for potassium ion battery(PIB) anodes.With a synergistic combination of X-ray tomography,structural probes,and charge reconfiguration,we encode the physical origins and structural evolution of electro-chemo-mechanical degradation in PIB anodes.By the multiple ion transport pathways created by the orderly hierarchical pores from "surface to bulk" and the homogeneous charge distribution governed in doped nanodomains,the anisotropic expansion can be significantly relieved with trace isoelectronic element doping into the host lattice,maintaining particle mechanical integrity.Our work presents a close relationship between doping chemistry and mechanical reliability,projecting a new pathway to reengineering electrode materials for next-generation energy storage.展开更多
The widespread applications of lithium-ion batteries(LIBs)generate tons of spent LIBs.Therefore,recycling LIBs is of paramount importance in protecting the environment and saving the resources.Current commercialized L...The widespread applications of lithium-ion batteries(LIBs)generate tons of spent LIBs.Therefore,recycling LIBs is of paramount importance in protecting the environment and saving the resources.Current commercialized LIBs mostly adopt layered oxides such as LiCoO_(2)(LCO)or LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)(NMC)as the cathode materials.Converting the intercalation-type spent oxides into conversion-type cathodes(such as metal fluorides(MFs))offers a valid recycling strategy and provides substantially improved energy densities for LIBs.Herein,two typical Co-based cathodes,LCO and LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NMC622),in spent LIBs were successfully converted to CoF_(2) and(Ni_(x)Co_(y)Mn_(z))F_(2) cathodes by a reduction and fluorination technique.The as converted CoF_(2) and(Ni_(x)Co_(y)Mn_(z))F_(2) delivered cell energy densities of 650 and 700 Wh/kg,respectively.Advanced atomic-level electron microscopy revealed that the used LCO and NMC622 were converted to highly phase pure Co metal and Ni_(0.6)Co_(0.2)Mn_(0.2) alloys in the used graphite-assisted reduction roasting,simultaneously producing the important product of Li_(2)CO_(3) using only environment friendly solvent.Our study provided a versatile strategy to convert the intercalation-type Co-based cathode in the spent LIBs into conversion-type MFs cathodes,which offers a new avenue to recycle the spent LIBs and substantially increase the energy densities of next generation LIBs.展开更多
Considering limited energy density of current lithium metal batteries(LMBs)due to low capacity of traditional intercalation-type cathodes,alternative high-energy cathodes are eagerly demanded.In this regard,conversion...Considering limited energy density of current lithium metal batteries(LMBs)due to low capacity of traditional intercalation-type cathodes,alternative high-energy cathodes are eagerly demanded.In this regard,conversion-type metal fluoride/sulfide/oxide cathodes have emerged great attention owing to their high theoretical specific capacities,supplying outstanding energy density for advanced LMBs.However,their low ionic/electrical conductivities,huge volume changes,sluggish reaction kinetics,and severe side reactions result in quick capacity fading and poor rate capability of LMBs.Recent research efforts on the conversiontype cathodes have brought new insights,as well as effective approaches toward realizing their excellent electrochemical performances.Here,the recent discoveries,challenges,and optimizing strategies including morphology regulation,phase structure engineering,surface coating,heterostructure construction,binder functionalization,and electrolyte design,are reviewed in detail.Finally,perspectives on the conversion-type metal fluoride/sulfide/oxide cathodes in LMBs are provided.It is believed that the conversion-type cathodes hold a promising future for the next-generation LMBs with high energy density.展开更多
Anion-hosting cathodes capable of reversibly storing large-size anions play a leading role in dual-ion batteries(DIBs). The purpose of the present review is to summarize the most promising anion-hosting cathodes for c...Anion-hosting cathodes capable of reversibly storing large-size anions play a leading role in dual-ion batteries(DIBs). The purpose of the present review is to summarize the most promising anion-hosting cathodes for current and late-stage DIBs. This review first summarizes the developments in conventional graphite cathodes, especially the latest advances in the graphiterelated research. Next, organic cathodes for the anion storage are discussed, including aromatic amine polymers, heterocyclic polymers, bipolar compounds, and all-carbon-unsaturated compounds. Then, the review focuses on the conversion-type cathodes with high theoretical specific capacities. Finally, the future research directions of the cathodes of DIBs are proposed.展开更多
Potassium-ion batteries(PIBs)have attracted tremendous attention during the past several years due to their abundant reserves,wide distribution,fast ionic conductivity,and high operating voltage.The primary obstacle i...Potassium-ion batteries(PIBs)have attracted tremendous attention during the past several years due to their abundant reserves,wide distribution,fast ionic conductivity,and high operating voltage.The primary obstacle impeding the com-mercialization of rechargeable PIBs is the lack of suitable high-performance anode materials.Carbon materials,known for their environmental friendliness,abundant availability,and outstanding comprehensive performance,have received extensive attention because they can be utilized directly as anodes or serve as a constrained matrix for conversion-/alloying-type anodes to enhance the electrochemical performance.Structural tuning and morphological modulation are two common strategies for modifying carbon materials.In this review,the recent progress in carbon materials aimed at enhancing the performance of PIBs through the utilization of these two strategies is systematically summarized.First,the effects of structural tuning and morphological modulation on the electrochemical properties of carbon materials and the corresponding storage mechanisms are reviewed.Second,the performance improvement mechanisms of conversion-/alloying-type anodes utilizing carbon scaf-folds based on these two strategies are systematically discussed.Third,the application of carbon materials based on various modification strategies in various advancedK+storage devices is reviewed.Finally,the challenges and perspectives for the further development of carbon-based materials for PIBs are highlighted.展开更多
Conversion-type anode materials hold great potential for Li+storage applications owing to their high specific capacity,while large volume expansion and poor electrical conductivity limit their rate and cycling perform...Conversion-type anode materials hold great potential for Li+storage applications owing to their high specific capacity,while large volume expansion and poor electrical conductivity limit their rate and cycling performances.Herein,a bimetal ZnMn-based metal-organic framework(ZnMn-MOF)is engineered for in situ conversion of MnO-encapsulated porous carbon(MnO/PC)composite.The templating and activation effects of coordinated Zn endow the converted PC matrix with a highly porous structure.This enhances the compatibility of PC matrix with MnO particles,resulting in the full encapsulation of MnO particles in the PC matrix.More significantly,the PC matrix provides enough void space to buffer the volume change,which fully wraps the MnO without crack or fracture during repeated cycling.As a result,MnO/PC shows high charge storage capability,extraordinary rate performance,and long-term cycling stability at the same time.Thus MnO/PC exhibits high delithiation capacities of 768mA h g^(-1)at 0.1Ag^(-1)and 487mA h g^(-1)at a high rate of 0.7Ag^(-1),combined with an unattenuated cycling performance after 500 cycles at 0.3Ag^(-1).More significantly,MnO/PC demonstrates a well-matched performance with the capacitive activated carbon electrode in a Li-ion capacitor(LIC)full cell.LIC demonstrates a high specific energy of 153.6W h kg^(-1)at 210W kg^(-1),combined with a specific energy of 71.8W h kg^(-1)at a high specific power of 63.0kW kg^(-1).展开更多
The large voltage hysteresis of the NiO anode,which owes much to the intermediate product Li_(2)NiO_(2),is one of the main obstacles to its practical application in lithium-ion batteries.In this work,we show that the ...The large voltage hysteresis of the NiO anode,which owes much to the intermediate product Li_(2)NiO_(2),is one of the main obstacles to its practical application in lithium-ion batteries.In this work,we show that the incorporation of Fe-and N-ions in the Nio lattice can suppress the formation of intermediate product Li_(2)NiO_(2)and thus greatly reduces the voltage hysteresis of the Nioanode from~1.2 to~0.9 V.In comparison with the pure Nio electrode,the Nio.5Feo.5O1-xNx anode exhibits significantly enhanced reversible specific capacity(959 mAh·g^(-1)at 0.3 A·g^(-1)),cycling stability(capacity retention of 96.1%at 100th cycle relative to the second cycle)and rate capability(442 at 10 A·g^(-1)).These results provide a practical method to enhance the lithium storage performance of the Nio anode and more importantly a new solution to the large voltage hysteresis of conversion-type anodes.展开更多
Copper sulfide(CuS)is a promising cathode for lithium-ion batteries(LIBs)due to its impeccable theoretical energy density(~1015 Wh·kg^(−1) and 4743 Wh·L^(−1)).However,it suffers from voltage decay leaded ene...Copper sulfide(CuS)is a promising cathode for lithium-ion batteries(LIBs)due to its impeccable theoretical energy density(~1015 Wh·kg^(−1) and 4743 Wh·L^(−1)).However,it suffers from voltage decay leaded energy density loss and low energy efficiency,which hinders its application.In this work,with combined ex-situ/in-situ X-ray diffraction(XRD)and electrochemical analysis,we explore detailed degradation mechanisms.For the voltage decay,it is attributed to a spontaneous reaction between CuS cathode and copper current collector(Cu CC).This reaction leads to energy density loss and active materials degradation(CuS→Cu_(1.81)S).As for energy efficiency,CuS undergoes a series of phase transformations.The main phase transition processes are CuS→α-LiCuS→Li_(2−x)Cu_(x)S+Cu→Li_(2)S+Cu for discharge;Li_(2)S+Cu→Li_(2−x)Cu_(x)S→β-LiCuS→CuS for charge.Here,α-LiCuS,β-LiCuS,and Li_(2−x)CuxS are newly identified phases.These phase changes are driven by topotactic-reaction-related copper diffusion and rearrangement.This work demonstrates the significance of transition-metal diffusion in the intermediates formation and phase change in conversion-type materials.展开更多
基金the financial support from NSFC(21975027)NSFCMAECI(51861135202).
文摘Developing advanced secondary batteries with low cost and high safety has attracted increasing research interests across the world.In particular,the aqueous zinc-ion battery(AZIB)has been regarded as a promising candidate owing to the high abundance and capacity of Zn metal.Currently,manganese-based and vanadium-based oxides are most common choices for cathode materials used in AZIBs,but they unfortunately show a moderate cell voltage and limited rate performance induced by slow intercalation-extraction kinetics of Zn^(2+)ions.To address these issues,alternative cathode systems with tunable redox potentials and intrinsic fast kinetics have been exploited.In the past few years,conversion-type cathodes of I_(2)and S have become the most illustrative examples to match or even surpass the performance of conventional metal oxide cathodes in AZIBs.Herein,we sum up most recent progress in conversion-type cathodes and focus on novel ideas and concepts in designing/modifying cathodes for AZIBs with high voltage/capacity.Additionally,potential directions and future efforts are tentatively proposed for further development of conversion-type cathodes,aiming to speed up the practical application of AZIBs.
基金National Natural Science Foundation of China(22322903,52072061)Natural Science Foundation of Sichuan,China(2023NSFSC1914)Beijing National Laboratory for Condensed Matter Physics(2023BNLCMPKF015)。
文摘Solid-state lithium batteries(SSLBs)are regarded as an essential growth path in energy storage systems due to their excellent safety and high energy density.In particular,SSLBs using conversion-type cathode materials have received widespread attention because of their high theoretical energy densities,low cost,and sustainability.Despite the great progress in research and development of SSLBs based on conversiontype cathodes,their practical applications still face challenges such as blocked ionic-electronic migration pathways,huge volume change,interfacial incompatibility,and expensive processing costs.This review focuses on the advantages and critical issues of coupling conversion-type cathodes with solid-state electrolytes(SSEs),as well as state-of-the-art progress in various promising cathodes(e.g.,FeS_(2),CuS,FeF_(3),FeF_(2),and S)in SSLBs.Furthermore,representative research on conversion-type solid-state full cells is discussed to offer enlightenment for their practical application.Significantly,the energy density exhibited by the S cathode stands out impressively,while sulfide SSEs and halide SSEs have demonstrated immense potential for coupling with conversion-type cathodes.Finally,perspectives on conversion-type cathodes are provided at the material,interface,composite electrode,and battery levels,with a view to accelerating the development of conversion-type cathodes for high-energy–density SSLBs.
基金supported by National Natural Science Foundation of China(Nos.52307239,52102300,52207234)the Natural Science Foundation of Hubei Province(Nos.2022CFB1003,2021CFA025).
文摘Conversion-type anode materials are highly desirable for Na-ion batteries(NIBs)due to their high theoretical capacity.Nevertheless,the active materials undergo severe expansion and pulverization during the sodiation,resulting in inferior cycling stability.Herein,a self-supporting three-dimensional(3D)graphene sponge decorated with Fe_(2)O_(3)nanocubes(rGO@Fe_(2)O_(3))is constructed.Specifically,the 3D graphene sponge with resilience and high porosity benefits to accommodate the volume expansion of the Fe_(2)O_(3)nanocubes and facilitates the rapid electrons/ions transport,enabling spatial confinement to achieve outstanding results.Besides,the free-standing rGO@Fe_(2)O_(3)can be directly used as an electrode without additional binders and conductive additives,which helps to obtain a higher energy density.Based on the total mass of the rGO@Fe_(2)O_(3)material,the rGO@Fe_(2)O_(3)anode presents a specific capacity of 859 mAh/g at 0.1 A/g.It also delivers an impressive cycling performance(327 mAh/g after 2000 cycles at 1 A/g)and a superior rate capacity(162mAh/g at 20 A/g).The coin-type Na_(3)V_(2)(PO_(4))_(3)@C//rGO@Fe_(2)O_(3)NIB exhibits an energy density of 265.3Wh/kg.This unique 3D ionic/electronic conductive network may provide new strategies to design advanced conversion-type anode materials for high-performance NIBs.
基金supported by China Postdoctoral Science Foundation(2020M673615XB)Special Projects on Regional Collaborative innovation-SCO Science and Technology Partnership Program,International Science and Technology Cooperation Program(2022E01056)+1 种基金Scientific Research Program Funded by Shaanxi Provincial Education Department(21JK0797)Natural Science Basic Research Program of Shaanxi(2021JM-322,2023-JC-QN-0131,2023-JC-YB-388)。
文摘δ-MnO_(2)has received constantly growing attention due to its stable tunnel-type crystalline structures for Zn^(2+)or Zn^(2+)/H^(+)intercalation,however,only partial Mn active sites exhibit electrochemical reactions,and most Mn atoms would stay the same to maintain the structure frame,indicative of low capacity and long cycling life theoretically.By comparison,for Cu-based conversion-typed materials,all Cu sites can perform electrochemical reactions if fully utilized,resulting in high rate capacity,however,short cycling life due to fracture,and even pulverization induced by volume changes during cycling.In this work,a hybrid cathode with intercalation and conversion behaviors is devised,in which intertwinedδ-MnO_(2)nanosheets shell wrap conversion-typed Cu_(2)O core firmly for stable conversion reaction during cycling.As a result,the optimized Cu_(2)O/MnO_(2)(denoted as MCO)cathode demonstrates the hybrid properties of long cycling life and high rate capacity,inheriting fromδ-MnO_(2)and Cu_(2)O,respectively.MCO cathodes with carbon cloth current collectors in full batteries deliver reversible capacities of 291.9 mA h g^(−1)at 1 A g^(−1),and retain 95%capacity at 20.0 A g^(−1)after 4300 cycles.Additionally,the energy density of 513.94 Wh kg^(−1)and power density of 7.2 kW kg^(−1)based on the MCO mass are exhibited,verifying its practical application.This work demonstrates the combination of intercalation and conversion in one electrochemical system and may provide new perspectives for the optimizing application of hybrid mechanisms.
基金the financial support from the National Postdoctoral Program for Innovation Talents(No.BX201700103)China Postdoctoral Science Foundation Funded Project(No.2018M633664).
文摘Potassium-ion batteries(KIBs)have become the most promising alternative to lithium-ion batteries for large-scale energy storage system due to their abundance and low cost.However,previous reports focused on the intercalation-type cathode materials usually showed an inferior capacity,together with a poor cyclic life caused by the repetitive intercalation of large-size K-ions,which hinders their practical application.Here,we combine the strategies of carbon coating,template etching and hydrothermal selenization to prepare yolk-shelled FeSe_(2)@N-doped carbon nanoboxes(FeSe_(2)@C NBs),where the inner highly-crystalline FeSe_(2)clusters are completely surrounded by the self-supported carbon shell.The integrated and highly conductive carbon shell not only provides a fast electron/ion diffusion channel,but also prevents the agglomeration of FeSe_(2)clusters.When evaluated as a conversion-type cathode material for KIBs,the FeSe_(2)@C NBs electrode delivers a relatively high specific capacity of 257 mAh/g at 100 mA/g and potential platform of about 1.6 V,which endow a high energy density of about 411 Wh/kg.Most importantly,by designing a robust host with large internal void space to accommodate the volumetric variation of the inner FeSe_(2)clusters,the battery based on FeSe_(2)@C NBs exhibits ultra-long cycle stability.Specifically,even after 700 cycles at 100 mA/g,a capacity of 221 mAh/g along with an average fading rate of only 0.02%can be retained,which achieves the optimal balance of high specific capacity and long-cycle stability.
基金financially supported by the National Natural Science Foundation of China(Nos.52004334,52003230,91962223 and 21473258)the Science and TechnologyInnovation Program of Hunan Province(No.2021RC2091)+3 种基金the China Postdoctoral Science Foundation(No.2021M692703)Natural Science Foundation of Hunan Province(No.2021JJ20073)National Key Research and Development Program of China(Nos.2018YFC1901601 and 2019YFC1907801)Collaborative Innovation Center for Clean and Efficient Utilization of Strategic Metal Mineral Resources,Foundation of State Key Laboratory of Mineral Processing(No.BGRIMM-KJSKL-2017-13)。
文摘Due to the high theoretical capacity and energy density,conversion-type metal fluorides have captured plenty of attentions but still suffer from the inferior kinetic behaviors and serious capacity fading.For addressing the issues above,the strategies of surface/interface engineering are utilized for the preparation of sphere-like porous FeF3@C materials,where the as-resulted sample displays the uniform particle size(~150 nm in radii)and the ultrathin carbon layers(thickness of~10 nm).Significantly,benefitting from the rich oxygen of precursor,the interfacial chemical bonds Fe-O-C are successfully constructed between carbon matrix and FeF3 materials,accompanying by the enhancements of ions/electrons(e-)conductivity and stability.When used as Li-storage cathodes,the initial lithium-ions storage capacity could reach up to~400mAh·g^(-1) at 0.1 A·g^(-1).Even at 1.0 A·g^(-1),the capacity could be still remained at about 210 mAh·g^(-1),with the retention of 85%after 400 cycles.Assisted by the detailed kinetic behaviors,the considerable electrochemical properties come from the enhanced diffusion-controlled contributions,whilst the segregation of Fe with LiF is effectively alleviated by unique architecture.Moreover,during cycling,solid electrolyte interface film is reversibly formed/decomposed.Thus,this work is expected to offer rational exterior/interfacial designing strategies for metalbased samples.
基金supported by the start-up fund and‘‘Young Scientist Studio”of Harbin Institute of Technology(HIT)the National Natural Science Foundation of China(No.U1932205)+1 种基金the Natural Science Funds of Heilongjiang Province(No.ZD2019B001)the HIT Research Institute(Zhao Yuan)of New Materials and the Intelligent Equipment Technology Co.,Ltd.Scientific and Technological Cooperation and Development Fund(No.2017KJHZ002)。
文摘Doping have been considered as a prominent strategy to stabilize crystal structure of battery materials during the insertion and removal of alkali ions.The instructive knowledge and experience acquired from doping strategies predominate in cathode materials,but doping principle in anodes remains unclear.Here,we demonstrate that trace element doping enables stable conversion-reaction and ensures structural integrity for potassium ion battery(PIB) anodes.With a synergistic combination of X-ray tomography,structural probes,and charge reconfiguration,we encode the physical origins and structural evolution of electro-chemo-mechanical degradation in PIB anodes.By the multiple ion transport pathways created by the orderly hierarchical pores from "surface to bulk" and the homogeneous charge distribution governed in doped nanodomains,the anisotropic expansion can be significantly relieved with trace isoelectronic element doping into the host lattice,maintaining particle mechanical integrity.Our work presents a close relationship between doping chemistry and mechanical reliability,projecting a new pathway to reengineering electrode materials for next-generation energy storage.
基金supported by the National Natural Science Foundation of China(Nos.U20A20336,21935009,52002346,52022088,51971245,22205191)the Science and Technology Innovation Program of Hunan Province(No.2021RC3109)+1 种基金the Natural Science Foundation of Hunan Province,China(No.2022JJ40446)Natural Science Foundation of Hebei Province(Nos.B2020203037,B2018203297).
文摘The widespread applications of lithium-ion batteries(LIBs)generate tons of spent LIBs.Therefore,recycling LIBs is of paramount importance in protecting the environment and saving the resources.Current commercialized LIBs mostly adopt layered oxides such as LiCoO_(2)(LCO)or LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)(NMC)as the cathode materials.Converting the intercalation-type spent oxides into conversion-type cathodes(such as metal fluorides(MFs))offers a valid recycling strategy and provides substantially improved energy densities for LIBs.Herein,two typical Co-based cathodes,LCO and LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NMC622),in spent LIBs were successfully converted to CoF_(2) and(Ni_(x)Co_(y)Mn_(z))F_(2) cathodes by a reduction and fluorination technique.The as converted CoF_(2) and(Ni_(x)Co_(y)Mn_(z))F_(2) delivered cell energy densities of 650 and 700 Wh/kg,respectively.Advanced atomic-level electron microscopy revealed that the used LCO and NMC622 were converted to highly phase pure Co metal and Ni_(0.6)Co_(0.2)Mn_(0.2) alloys in the used graphite-assisted reduction roasting,simultaneously producing the important product of Li_(2)CO_(3) using only environment friendly solvent.Our study provided a versatile strategy to convert the intercalation-type Co-based cathode in the spent LIBs into conversion-type MFs cathodes,which offers a new avenue to recycle the spent LIBs and substantially increase the energy densities of next generation LIBs.
基金funded by the National Natural Science Foundation of China(Nos.51672069 and 52072112)Program for Innovative Research Team in Science and Technology in the University of Henan Province(No.20IRTSTHN012)+2 种基金Henan Overseas Expertise Introduction Center for Discipline Innovation(No.CXJD2021003)Science and Technology Development Project of Henan Province(No.202102210105)Zhongyuan Thousand Talents Program of Henan Province(No.ZYQR201912155).
文摘Considering limited energy density of current lithium metal batteries(LMBs)due to low capacity of traditional intercalation-type cathodes,alternative high-energy cathodes are eagerly demanded.In this regard,conversion-type metal fluoride/sulfide/oxide cathodes have emerged great attention owing to their high theoretical specific capacities,supplying outstanding energy density for advanced LMBs.However,their low ionic/electrical conductivities,huge volume changes,sluggish reaction kinetics,and severe side reactions result in quick capacity fading and poor rate capability of LMBs.Recent research efforts on the conversiontype cathodes have brought new insights,as well as effective approaches toward realizing their excellent electrochemical performances.Here,the recent discoveries,challenges,and optimizing strategies including morphology regulation,phase structure engineering,surface coating,heterostructure construction,binder functionalization,and electrolyte design,are reviewed in detail.Finally,perspectives on the conversion-type metal fluoride/sulfide/oxide cathodes in LMBs are provided.It is believed that the conversion-type cathodes hold a promising future for the next-generation LMBs with high energy density.
基金the financial support from National Key R&D Program of China (2022YFB2402600)National Natural Science Foundation of China (52125105, 51972329)+4 种基金NSFC/RGC Joint Research Scheme (Project No:N_City U104/20 and52061160484)Science and Technology Planning Project of Guangdong Province (2021TQ05L894)Shenzhen Science and Technology Planning Project (JSGG20211108092801002, JSGG20220831104004008)Quality and Reform Project of Guangdong province undergraduate teaching(XQSYS-2222873)Key Scientific Research Projects of General Universities in Guangdong Province (2021KCXTD086)。
文摘Anion-hosting cathodes capable of reversibly storing large-size anions play a leading role in dual-ion batteries(DIBs). The purpose of the present review is to summarize the most promising anion-hosting cathodes for current and late-stage DIBs. This review first summarizes the developments in conventional graphite cathodes, especially the latest advances in the graphiterelated research. Next, organic cathodes for the anion storage are discussed, including aromatic amine polymers, heterocyclic polymers, bipolar compounds, and all-carbon-unsaturated compounds. Then, the review focuses on the conversion-type cathodes with high theoretical specific capacities. Finally, the future research directions of the cathodes of DIBs are proposed.
基金financially supported by the Postdoctoral Innovation Talents Support Program of China(BX2021067)the Pujiang Talent Program of Shanghai(20PJ1401400)+2 种基金the Open Fund of the Guangdong Provincial Key Laboratory of Advance Energy Storage Materials(Grant No.asem202101)Aerospace Innovation Fund of Shanghai(SAST2020098)the China Postdoctoral Science Foundation(No.2022M710711).
文摘Potassium-ion batteries(PIBs)have attracted tremendous attention during the past several years due to their abundant reserves,wide distribution,fast ionic conductivity,and high operating voltage.The primary obstacle impeding the com-mercialization of rechargeable PIBs is the lack of suitable high-performance anode materials.Carbon materials,known for their environmental friendliness,abundant availability,and outstanding comprehensive performance,have received extensive attention because they can be utilized directly as anodes or serve as a constrained matrix for conversion-/alloying-type anodes to enhance the electrochemical performance.Structural tuning and morphological modulation are two common strategies for modifying carbon materials.In this review,the recent progress in carbon materials aimed at enhancing the performance of PIBs through the utilization of these two strategies is systematically summarized.First,the effects of structural tuning and morphological modulation on the electrochemical properties of carbon materials and the corresponding storage mechanisms are reviewed.Second,the performance improvement mechanisms of conversion-/alloying-type anodes utilizing carbon scaf-folds based on these two strategies are systematically discussed.Third,the application of carbon materials based on various modification strategies in various advancedK+storage devices is reviewed.Finally,the challenges and perspectives for the further development of carbon-based materials for PIBs are highlighted.
基金supported by the National Natural Science Foundation of China(21905148)China Postdoctoral Science Foundation(2019T120567 and 2017M612184)+2 种基金the 1000-Talents Planthe World-Class Discipline Programthe Taishan Scholars Advantageous and Distinctive Discipline Program of Shandong province for supporting the research team of energy storage materials.
文摘Conversion-type anode materials hold great potential for Li+storage applications owing to their high specific capacity,while large volume expansion and poor electrical conductivity limit their rate and cycling performances.Herein,a bimetal ZnMn-based metal-organic framework(ZnMn-MOF)is engineered for in situ conversion of MnO-encapsulated porous carbon(MnO/PC)composite.The templating and activation effects of coordinated Zn endow the converted PC matrix with a highly porous structure.This enhances the compatibility of PC matrix with MnO particles,resulting in the full encapsulation of MnO particles in the PC matrix.More significantly,the PC matrix provides enough void space to buffer the volume change,which fully wraps the MnO without crack or fracture during repeated cycling.As a result,MnO/PC shows high charge storage capability,extraordinary rate performance,and long-term cycling stability at the same time.Thus MnO/PC exhibits high delithiation capacities of 768mA h g^(-1)at 0.1Ag^(-1)and 487mA h g^(-1)at a high rate of 0.7Ag^(-1),combined with an unattenuated cycling performance after 500 cycles at 0.3Ag^(-1).More significantly,MnO/PC demonstrates a well-matched performance with the capacitive activated carbon electrode in a Li-ion capacitor(LIC)full cell.LIC demonstrates a high specific energy of 153.6W h kg^(-1)at 210W kg^(-1),combined with a specific energy of 71.8W h kg^(-1)at a high specific power of 63.0kW kg^(-1).
基金support by the National Natural Science Foundation of China(Grant No.51767021)the Development Funds of Hunan Wedid Materials Technology Co.,Ltd.,China(Grant No.738010241)the Southwest Petroleum University(Grant No.2021KSZ05009).
文摘The large voltage hysteresis of the NiO anode,which owes much to the intermediate product Li_(2)NiO_(2),is one of the main obstacles to its practical application in lithium-ion batteries.In this work,we show that the incorporation of Fe-and N-ions in the Nio lattice can suppress the formation of intermediate product Li_(2)NiO_(2)and thus greatly reduces the voltage hysteresis of the Nioanode from~1.2 to~0.9 V.In comparison with the pure Nio electrode,the Nio.5Feo.5O1-xNx anode exhibits significantly enhanced reversible specific capacity(959 mAh·g^(-1)at 0.3 A·g^(-1)),cycling stability(capacity retention of 96.1%at 100th cycle relative to the second cycle)and rate capability(442 at 10 A·g^(-1)).These results provide a practical method to enhance the lithium storage performance of the Nio anode and more importantly a new solution to the large voltage hysteresis of conversion-type anodes.
基金supported by the National Natural Science Foundation of China(No.52072061)the Natural Science Foundation of Sichuan,China(No.2023NSFSC1914).
文摘Copper sulfide(CuS)is a promising cathode for lithium-ion batteries(LIBs)due to its impeccable theoretical energy density(~1015 Wh·kg^(−1) and 4743 Wh·L^(−1)).However,it suffers from voltage decay leaded energy density loss and low energy efficiency,which hinders its application.In this work,with combined ex-situ/in-situ X-ray diffraction(XRD)and electrochemical analysis,we explore detailed degradation mechanisms.For the voltage decay,it is attributed to a spontaneous reaction between CuS cathode and copper current collector(Cu CC).This reaction leads to energy density loss and active materials degradation(CuS→Cu_(1.81)S).As for energy efficiency,CuS undergoes a series of phase transformations.The main phase transition processes are CuS→α-LiCuS→Li_(2−x)Cu_(x)S+Cu→Li_(2)S+Cu for discharge;Li_(2)S+Cu→Li_(2−x)Cu_(x)S→β-LiCuS→CuS for charge.Here,α-LiCuS,β-LiCuS,and Li_(2−x)CuxS are newly identified phases.These phase changes are driven by topotactic-reaction-related copper diffusion and rearrangement.This work demonstrates the significance of transition-metal diffusion in the intermediates formation and phase change in conversion-type materials.
