Sodium superionic conductors(NASICONs)have attracted enormous attention owing to their excellent ionic diffusion and structural stability.However,the high cost of vanadium,limited capacity due to fewer redox reactions...Sodium superionic conductors(NASICONs)have attracted enormous attention owing to their excellent ionic diffusion and structural stability.However,the high cost of vanadium,limited capacity due to fewer redox reactions,and low electronic conductivity restrict their practical application.Herein,we designed Na_(3.5)V_(0.5)Mn_(0.5)Fe_(0.5)Ti_(0.5)(PO_(4))3 (NVMFTP)medium entropy NASICON with multi-electron reactions as a fast sodium storage cathode for sodium-ion batteries(SIBs).The incorporation of Fe,Mn and Ti not only reduces the cost but also activates multi-redox reactions of V^(2+)/V^(3+),Ti^(3+)/Ti^(4+),Fe^(2+)/Fe^(3+),V^(3+)/V^(4+),Mn^(2+)/Mn^(3+),V^(4+)/V^(5+).Owing to distinctive structural design with medium entropy,the NVMFTP delivered 168 mAh·g^(−1) at 0.5C with a remarkable rate capability of 93.51 mAh·g^(−1) at 60C and steady long-term cycling performance till 5000 cycles.More importantly,NVMFTP takes only 11 min to achieve 80%SOC at 5C.The in-situ and ex-situ X-ray diffraction(XRD)further demonstrate reversible multi-electron reaction mechanisms of slow charging and fast charging.NVMFTP/HC full cell shows 110 mAh·g^(−1) capacity and 208 Wh·kg^(−1) energy density.This study will provide comprehensive insight into developing low-cost,cutting-edge materials for SIBs.展开更多
钠离子电池被广泛研究用于储能应用,但实现同时具有高能量密度、稳定性和快速充放电性能的正极材料仍然是一个关键的挑战。本研究合成了一系列NASICON型Na_(3.5−x)Mn_(0.5)V_(1.5−x)Zrx(PO_(4))_(3)/C材料,并掺入Mn、V和Zr元素探讨其对...钠离子电池被广泛研究用于储能应用,但实现同时具有高能量密度、稳定性和快速充放电性能的正极材料仍然是一个关键的挑战。本研究合成了一系列NASICON型Na_(3.5−x)Mn_(0.5)V_(1.5−x)Zrx(PO_(4))_(3)/C材料,并掺入Mn、V和Zr元素探讨其对电化学性能的影响。通过在Mn和V的基础上引入Zr,提出一种激活V4+/V5+氧化还原反应新的策略,从而提升能量密度。此外,Zr掺入通过拓宽离子通道并产生额外的钠离子空位,显著促进钠离子迁移,增强电极反应动力学和整体性能。结果表明,Na_(3.5−x)Mn_(0.5)V_(1.5−x)Zrx(PO_(4))_(3)/C材料表现出优异的循环稳定性,在800次循环后保持90%的容量,并具备高倍率性能(20C时,放电比容量为84 m Ah·g^(-1)),显著优于原始的Na_(3.5−x)Mn_(0.5)V_(1.5−x)Zrx(PO_(4))_(3)/C材料。该研究为开发高效且可持续钠离子电池提供了有效途径。展开更多
All-solid-state sodium(Na)-metal batteries(ASSSMBs)are considered promising candidates for large-scale energy storage systems due to their abundant sodium resources,unparalleled safety performance,and impressive energ...All-solid-state sodium(Na)-metal batteries(ASSSMBs)are considered promising candidates for large-scale energy storage systems due to their abundant sodium resources,unparalleled safety performance,and impressive energy density.Na superionic conductors(NASICONs)are among the best enablers of ASSSMBs in view of their high ionic conductivity,ease of synthesis,and excellent thermal stability and good electrochemical/chemical compatibility with common electrodes.However,challenges surrounding the NASICON/electrode interface,such as high interfacial resistance and dendrite formation,have hindered the development of practical ASSSMBs based on NASICONs.This review starts with an explicit summary of the interface problems between the metallic Na anode and NASICON arising from mechanical,chemical,and electrochemical aspects(i.e.,poor interface contact,insulating side-reaction products,and irregular dendrite growth).Subsequently,we systematically analyze and logically categorize modification strategies for addressing anode interface problems and provide a comprehensive discussion on the underlying enhancement mechanisms.As such,we identify underlying and universal interface enhancement mechanisms by comparatively studying various modification strategies.Furthermore,we briefly summarize the challenges in the cathode/electrolyte interface and early-stage research efforts in constructing stable cathode/electrolyte interface and fabricating high-performance composite cathodes.Finally,key suggestions and future prospectives for the advancement of NASICON-based ASSSMBs are outlined.展开更多
In recent years,the development and research of electrochemical energy storage systems that can efficiently transform chemical energy into electrical energy with a long service life have become a key area of study.Sod...In recent years,the development and research of electrochemical energy storage systems that can efficiently transform chemical energy into electrical energy with a long service life have become a key area of study.Sodium-ion batteries,leveraging their chemical similarity to lithium-ion batteries,along with their abundant resources and low cost,are seen as a viable alternative to lithium-ion batteries.Additionally,all-solid-state sodium-ion batteries have drawn significant attention due to safety considerations.Among the solid electrolytes for all-solid-state sodium-ion batteries,the NASICON solid-state electrolyte emerges as one of the most promising choices for sodium battery solid electrolytes.However,to date,there has not been a comprehensive review summarizing the existing problems of NASICON electrolyte materials and the corresponding specific modification methods.This review simply summarizes the present issues of NASICON for all-solid-state sodium-ion batteries,such as,the low ionic conductivity,the poor interface stability and compatibility,and the dendrite formation.Then,the corresponding solutions to address these issues are discussed,including the ion doping,the interface modification,the sintering parameters optimization,and the composite electrolytes regulation.Finally,the perspectives of NASICON solid-state electrolyte are discussed.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52027801 and 92263203)the National Key R&D Program of China(Nos.2022YFA1203902 and 2022YFA1200093)and the China-Germany Collaboration Project(No.M-0199)。
文摘Sodium superionic conductors(NASICONs)have attracted enormous attention owing to their excellent ionic diffusion and structural stability.However,the high cost of vanadium,limited capacity due to fewer redox reactions,and low electronic conductivity restrict their practical application.Herein,we designed Na_(3.5)V_(0.5)Mn_(0.5)Fe_(0.5)Ti_(0.5)(PO_(4))3 (NVMFTP)medium entropy NASICON with multi-electron reactions as a fast sodium storage cathode for sodium-ion batteries(SIBs).The incorporation of Fe,Mn and Ti not only reduces the cost but also activates multi-redox reactions of V^(2+)/V^(3+),Ti^(3+)/Ti^(4+),Fe^(2+)/Fe^(3+),V^(3+)/V^(4+),Mn^(2+)/Mn^(3+),V^(4+)/V^(5+).Owing to distinctive structural design with medium entropy,the NVMFTP delivered 168 mAh·g^(−1) at 0.5C with a remarkable rate capability of 93.51 mAh·g^(−1) at 60C and steady long-term cycling performance till 5000 cycles.More importantly,NVMFTP takes only 11 min to achieve 80%SOC at 5C.The in-situ and ex-situ X-ray diffraction(XRD)further demonstrate reversible multi-electron reaction mechanisms of slow charging and fast charging.NVMFTP/HC full cell shows 110 mAh·g^(−1) capacity and 208 Wh·kg^(−1) energy density.This study will provide comprehensive insight into developing low-cost,cutting-edge materials for SIBs.
文摘钠离子电池被广泛研究用于储能应用,但实现同时具有高能量密度、稳定性和快速充放电性能的正极材料仍然是一个关键的挑战。本研究合成了一系列NASICON型Na_(3.5−x)Mn_(0.5)V_(1.5−x)Zrx(PO_(4))_(3)/C材料,并掺入Mn、V和Zr元素探讨其对电化学性能的影响。通过在Mn和V的基础上引入Zr,提出一种激活V4+/V5+氧化还原反应新的策略,从而提升能量密度。此外,Zr掺入通过拓宽离子通道并产生额外的钠离子空位,显著促进钠离子迁移,增强电极反应动力学和整体性能。结果表明,Na_(3.5−x)Mn_(0.5)V_(1.5−x)Zrx(PO_(4))_(3)/C材料表现出优异的循环稳定性,在800次循环后保持90%的容量,并具备高倍率性能(20C时,放电比容量为84 m Ah·g^(-1)),显著优于原始的Na_(3.5−x)Mn_(0.5)V_(1.5−x)Zrx(PO_(4))_(3)/C材料。该研究为开发高效且可持续钠离子电池提供了有效途径。
基金The authors are grateful for financial support from the National Natural Science Foundation of China(52202199)Anhui Provincial Natural Science Foundation(2108085QE202)start-up grants from Anhui University(S020318008/007,S020118002/060).
文摘All-solid-state sodium(Na)-metal batteries(ASSSMBs)are considered promising candidates for large-scale energy storage systems due to their abundant sodium resources,unparalleled safety performance,and impressive energy density.Na superionic conductors(NASICONs)are among the best enablers of ASSSMBs in view of their high ionic conductivity,ease of synthesis,and excellent thermal stability and good electrochemical/chemical compatibility with common electrodes.However,challenges surrounding the NASICON/electrode interface,such as high interfacial resistance and dendrite formation,have hindered the development of practical ASSSMBs based on NASICONs.This review starts with an explicit summary of the interface problems between the metallic Na anode and NASICON arising from mechanical,chemical,and electrochemical aspects(i.e.,poor interface contact,insulating side-reaction products,and irregular dendrite growth).Subsequently,we systematically analyze and logically categorize modification strategies for addressing anode interface problems and provide a comprehensive discussion on the underlying enhancement mechanisms.As such,we identify underlying and universal interface enhancement mechanisms by comparatively studying various modification strategies.Furthermore,we briefly summarize the challenges in the cathode/electrolyte interface and early-stage research efforts in constructing stable cathode/electrolyte interface and fabricating high-performance composite cathodes.Finally,key suggestions and future prospectives for the advancement of NASICON-based ASSSMBs are outlined.
基金Projects(52204378,22309209)supported by the National Natural Science Foundation of ChinaProject(2023JJ40709)supported by the Natural Science Foundation of Hunan Province,China。
文摘In recent years,the development and research of electrochemical energy storage systems that can efficiently transform chemical energy into electrical energy with a long service life have become a key area of study.Sodium-ion batteries,leveraging their chemical similarity to lithium-ion batteries,along with their abundant resources and low cost,are seen as a viable alternative to lithium-ion batteries.Additionally,all-solid-state sodium-ion batteries have drawn significant attention due to safety considerations.Among the solid electrolytes for all-solid-state sodium-ion batteries,the NASICON solid-state electrolyte emerges as one of the most promising choices for sodium battery solid electrolytes.However,to date,there has not been a comprehensive review summarizing the existing problems of NASICON electrolyte materials and the corresponding specific modification methods.This review simply summarizes the present issues of NASICON for all-solid-state sodium-ion batteries,such as,the low ionic conductivity,the poor interface stability and compatibility,and the dendrite formation.Then,the corresponding solutions to address these issues are discussed,including the ion doping,the interface modification,the sintering parameters optimization,and the composite electrolytes regulation.Finally,the perspectives of NASICON solid-state electrolyte are discussed.
文摘以Li_2CO_3、ZrO_2、Er_2O_3、(NH_4)_2HPO_4为初始原料,采用传统的固相法合成了Li Zr_2(PO_4)_3基NASICON型固态电解质材料Li_(1+x)Er_xZr_(2-x)(PO_4)_3(x=0~0.2)。通过无压烧结和放电等离子烧结法(SPS)烧结得到致密的电解质片,采用无压烧结过程中在样品中加入少许的PVA使得样品烧结致密。利用XRD、SEM、EIS分别测得样品的结构、形貌以及电性能。结果表明:通过SPS烧结的样品致密度可以达到92.6%。使用SPS烧结后的样品Li1.15Er0.15Zr1.85(PO_4)_3在常温下的晶粒和总电导率分别为2.2×10^(-4)和8.8×10^(-6) S·cm^(-1)。样品的激活能为0.36 e V。
