Aqueous zinc-ion batteries(ZIBs)have got wide attention with the increasing demands for energy resource recently.It has a number of merits compared with lithium-ion batteries,such as enhanced safety,low cost and envir...Aqueous zinc-ion batteries(ZIBs)have got wide attention with the increasing demands for energy resource recently.It has a number of merits compared with lithium-ion batteries,such as enhanced safety,low cost and environmental friendliness.Vanadium-based materials have been developed to serve as the cathodes of ZIBs for many years.But there are also some challenges to construct high performance ZIBs in the future.Herein,we reviewed the research progress of vanadium-based cathodes and discussed the energy storage mechanisms in ZIBs.In addition,we summarized the major challenges faced by vanadium-based cathodes and the corresponding ways to improve electrochemical performance of ZIBs.Finally,some excellent vanadium-based cathodes are summarized to pave the way for future research in ZIBs.展开更多
As an emerging energy storage device with high-safety aqueous electrolytes, low-cost, environmental benignity and large-reserves, the rechargeable aqueous zinc-ion batteries(AZIBs) have attracted more and more attenti...As an emerging energy storage device with high-safety aqueous electrolytes, low-cost, environmental benignity and large-reserves, the rechargeable aqueous zinc-ion batteries(AZIBs) have attracted more and more attention. Vanadium-based compounds are also supposed as the potential candidate cathode materials for AZIBs due to their wide variety of phases, variable crystal structures and high theoretical capacity. In this review, the recent progress in the development of vanadium-based materials was summarized,and the relationship between the crystal structure types of active materials and Zn-ion transport mechanism was highlighted. During the charge-discharge process, the different electrostatic repulsion between the cations of vanadium-based compounds with different crystal structures and Zn^(2+)results in a variety of the Zn-ion storage mechanisms, which can be significant guidance for designing the advanced batteryelectrode materials for AZIBs. Furthermore, other factors associated with the storage mechanisms, such as electrolyte components and electrode morphology, are discussed. Finally, the strategies to improve the electrical conductivity, inhibit the dissolution and stabilize the crystal structure of vanadium-based compounds are proposed and the future prospects for developing high-energy-density AZIBs are presented.展开更多
Mn-based layered oxides(KMO)have emerged as one of the promising low-cost cathodes for potassiumion batteries(PIBs).However,due to the multiple-phase transitions and the distortion in the MnO6structure induced by the ...Mn-based layered oxides(KMO)have emerged as one of the promising low-cost cathodes for potassiumion batteries(PIBs).However,due to the multiple-phase transitions and the distortion in the MnO6structure induced by the Jahn-Teller(JT)effect associated with Mn-ion,the cathode exhibits poor structural stability.Herein,we propose a strategy to enhance structural stability by introducing robust metal-oxygen(M-O)bonds,which can realize the pinning effect to constrain the distortion in the transition metal(TM)layer.Concurrently,all the elements employed have exceptionally high crustal abundance.As a proof of concept,the designed K_(0.5)Mn_(0.9)Mg_(0.025)Ti_(0.025)Al_(0.05)O_(2)cathode exhibited a discharge capacity of approximately 100 mA h g^(-1)at 20 mA g^(-1)with 79%capacity retention over 50 cycles,and 73%capacity retention over 200 cycles at 200 mA g^(-1),showcased much better battery performance than the designed cathode with less robust M-O bonds.The properties of the formed M-O bonds were investigated using theoretical calculations.The enhanced dynamics,mitigated JT effect,and improved structural stability were elucidated through the in-situ X-ray diffractometer(XRD),in-situ electrochemical impedance spectroscopy(EIS)(and distribution of relaxation times(DRT)method),and ex-situ X-ray absorption fine structure(XAFS)tests.This study holds substantial reference value for the future design of costeffective Mn-based layered cathodes for PIBs.展开更多
Sulfide-based all-solid-state lithium batteries suffer from electrochemo-mechanical damage to Ni-rich oxide-based cathode active materials(CAMs),primarily caused by severe volume changes,results in significant stress ...Sulfide-based all-solid-state lithium batteries suffer from electrochemo-mechanical damage to Ni-rich oxide-based cathode active materials(CAMs),primarily caused by severe volume changes,results in significant stress and strain,causes micro-cracks and interfacial contact loss at potentials>4.3 V(vs.Li/Li^(+)).Quantifying micro-cracks and voids in CAMs can reveal the degradation mechanisms of Ni-rich oxidebased cathodes during electrochemical cycling.Nonetheless,the origin of electrochemical-mechanical damage remains unclear.Herein,We have developed a multifunctional PEG-based soft buffer layer(SBL)on the surface of carbon black(CB).This layer functions as a percolation network in the single crystal LiNi_(0.83)Co_(0.07)Mn_(0.1)O_(2)and Li_(6)PS_(5)Cl composite cathode layer,ensuring superior ionic conductivity,reducing void formation and particle cracking,and promoting uniform utilization of the cathode active material in all-solid-state lithium batteries(ASSLBs).High-angle annular dark-field STEM combined with nanoscale X-ray holo-tomography and plasma-focused ion beam scanning electron microscopy confirmed that the PEG-based SBL mitigated strain induced by reaction heterogeneity in the cathode.This strain produces lattice stretches,distortions,and curved transition metal oxide layers near the surface,contributing to structural degradation at elevated voltages.Consequently,ASSLBs with a LiNi_(0.83)Co_(0.07)Mn_(0.1)O_(2)cathode containing LCCB-10(CB/PEG mass ratio:100/10)demonstrate a high areal capacity(2.53 mAh g^(-1)/0.32 mA g^(-1))and remarkable rate capability(0.58 mAh g^(-1)at 1.4 mA g^(-1)),with88%capacity retention over 1000 cycles.展开更多
The implementation of ultrahigh-Ni cathodes in high-energy lithium-ion batteries(LIBs)is constrained by significant structural and interfacial degradation during cycling.In this study,doping-induced surface restructur...The implementation of ultrahigh-Ni cathodes in high-energy lithium-ion batteries(LIBs)is constrained by significant structural and interfacial degradation during cycling.In this study,doping-induced surface restructuring in ultrahigh-nickel cathode materials is rapidly facilitated through an ultrafast Joule heating method.Density functional theory(DFT)calculations,synchrotron X-ray absorption spectroscopy(XAS),and single-particle force test confirmed the establishment of a stable crystal framework and lattice oxygen,which mitigated H2-H3 phase transitions and improved structural reversibility.Additionally,the Sc doping process exhibits a pinning effect on the grain boundaries,as shown by scanning transmission electron microscopy(STEM),enhancing Li~+diffusion kinetics and decreasing mechanical strain during cycling.The in situ development of a cation-mixing layer at grain boundaries also creates a robust cathode/electrolyte interphase,effectively reducing interfacial parasitic reactions and transition metal dissolution,as validated by STEM and time-of-flight secondary ion mass spectrometry(TOF-SIMS).These synergistic modifications reduce particle cracking and surface/interface degradation,leading to enhanced rate capability,structural integrity,and thermal stability.Consequently,the optimized Sc-modified ultrahigh-Ni cathode(Sc-1)exhibits 93.99%capacity retention after 100 cycles at 1 C(25℃)and87.06%capacity retention after 100 cycles at 1 C(50℃),indicating excellent cycling and thermal stability.By presenting a one-step multifunctional modification approach,this research delivers an extensive analysis of the mechanisms governing the structure,microstructure,and interface properties of nickel-rich layered cathode materials(NCMs).These results underscore the potential of ultrahigh-Ni cathodes as viable candidates for advanced lithium-ion batteries(LIBs)in next-generation electric vehicles(EVs).展开更多
Lithium-rich manganese-based cathodes(LRMs)have garnered significant attention as promising candidates for highenergy-density batteries due to their exceptional specific capacity exceeding 300 mAh/g,achieved through s...Lithium-rich manganese-based cathodes(LRMs)have garnered significant attention as promising candidates for highenergy-density batteries due to their exceptional specific capacity exceeding 300 mAh/g,achieved through synergistic anionic and cationic redox reactions.However,these materials face challenges including oxygen release-induced structural degradation and consequent capacity fading.To address these issues,strategies such as surface modification and bulk phase engineering have been explored.In this study,we developed a facile and cost-effective quenching approach that simultaneously modifies both surface and bulk characteristics.Multi-scale characterization and computational analysis reveal that rapid cooling partially preserves the high-temperature disordered phase in the bulk structure,thereby enhancing the structural stability.Concurrently,Li^(+)/H^(+)exchange at the surface forms a robust rock-salt/spinel passivation layer,effectively suppressing oxygen evolution and mitigating interfacial side reactions.This dual modification strategy demonstrates a synergistic stabilization effect.The enhanced oxygen redox activity coexists with the improved structural integrity,leading to superior electrochemical performance.The optimized cathode delivers an initial discharge capacity approaching 307.14 mAh/g at 0.1 C and remarkable cycling stability with 94.12%capacity retention after 200 cycles at 1 C.This study presents a straightforward and economical strategy for concurrent surface–bulk modification,offering valuable insights for designing high-capacity LRM cathodes with extended cycle life.展开更多
Ni-rich layered oxide cathode materials such as LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NCM811)face poor interfacial stability and serious side reactions with sulfide solid-state electrolytes.This problem is thought to be exa...Ni-rich layered oxide cathode materials such as LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NCM811)face poor interfacial stability and serious side reactions with sulfide solid-state electrolytes.This problem is thought to be exacerbated by the gradually accumulated basicity of the surface with the Ni content increasing.Herein,the acidic Li_(3)PO_(4)coating layer on NCM811 particles is introduced by ball-milling approach to neutralize the basicity and aggrandize the interfacial stability.The tailored surface structure and components of NCM811 not only suppress the direct contact of cathode particles with sulfide solid-state electrolyte,but also facilitate electrochemical dynamics by driving the Li+migration across the interface and promoting the electron exchange.Thus,cells with Li_(3)PO_(4)coating layer yield 101.3 mAh g^(-1)specific capacity at 2.0 C and highly reversed discharging capacity after suffering from harsh work conditions.Additionally,the stable coating layer broadens the electrochemical windows of cells,delivering long cycle stability(>100 cycles 0.5 C).This contribution highlights the importance of basicity regulation of Ni-rich layered oxide cathode and offers a low-cost and effective approach to design the interfacial structures for the development of all solid-state batteries.展开更多
Cathode materials with excellent performance are a key to exploiting aqueous zinc ion batteries.In this study,we developed a cathode material for aqueous zinc ion batteries using an in situ anion–cation pre-intercala...Cathode materials with excellent performance are a key to exploiting aqueous zinc ion batteries.In this study,we developed a cathode material for aqueous zinc ion batteries using an in situ anion–cation pre-intercalation strategy with a metal–organic framework.In situ doping of S and Zn in a vanadium-based metal–organic framework structure forms a Zn–S pre-intercalated vanadium oxide((Zn,S)VO)composite.The combination of the additional Zn^(2+)storage sites with pseudocapacitive behavior on the amorphous surface of the enriched oxygen defects and the enhancement of the structural toughness by strong ionic bonding together the unique nanostructure of the nanochains by the process of‘‘oriented attachment’’led to the preparation of the high-performance(Zn,S)VO composite.The results show that the(Zn,S)VO electrode has a capacity of 602.40 mAh·g^(-1)at 0.1 A·g^(-1),an initial discharge capacity of 300.60 mAh·g^(-1)at 10.0 A·g^(-1),and a capacity retention rate of 99.93%after 3,500 cycles.Using the gel electrolyte,the capacity of(Zn,S)VO electrode is 233.15 and 650.93 mAh·g^(-1)at 0.2 A·g^(-1)in-20 and 60°C environments,respectively.Meanwhile,the(Zn,S)VO flexible batteries perform well in harsh environments.展开更多
Lithium-rich manganese-based cathode materials(LMCMs)have garnered significant attention in power lithium-ion batteries(LIBs)and energy storage systems due to their superior energy density and costeffectiveness.Howeve...Lithium-rich manganese-based cathode materials(LMCMs)have garnered significant attention in power lithium-ion batteries(LIBs)and energy storage systems due to their superior energy density and costeffectiveness.However,the commercial application of LMCMs is hindered by challenges such as low initial coulombic efficiency,severe voltage decay,and inferior cycling performance.Surface structure degradation has been confirmed as a critical factor contributing to the electrochemical performance deterioration of LMCMs.Herein,we review the recent progress in surface engineering of LMCMs towards next-generation LIBs.Besides classical surface coating,mechanism and functions of surface oxygen vacancies for greatly boosting the electrochemical performance of LMCMs are also summarized in detail.Finally,we discuss the emerging trends and propose future research directions of surface engineering of LMCMs for achieving more efficient improvements.This work underscores the indispensable potential of surface engineering in enhancing the surface structure stability and electrochemical performance of LMCMs as promising candidates for next-generation high-energy LIBs.Synergistic integration of surface engineering and single-crystal technology will be a promising modification strategy for significantly promoting the commercialization of LMCMs,and the corresponding synergistic mechanisms urgently need to be studied for rationally designing high-performance electrodes.More efforts will be devoted to understand the surface engineering of LMCMs for the large-scale application of high-energy LIBs.展开更多
Developing cost-effective single-crystalline Ni-rich Co-poor cathodes operating at high-voltage is one of the most important ways to achieve higher energy Li-ion batteries. However, the Li/O loss and Li/Ni mixing unde...Developing cost-effective single-crystalline Ni-rich Co-poor cathodes operating at high-voltage is one of the most important ways to achieve higher energy Li-ion batteries. However, the Li/O loss and Li/Ni mixing under high-temperature lithiation result in electrochemical kinetic hysteresis and structural instability. Herein, we report a highly-ordered single-crystalline LiNi0.85Co0.05Mn0.10O2(NCM85) cathode by doping K+and F-ions. To be specific, the K-ion as a fluxing agent can remarkably decrease the solid-state lithiation temperature by ~30°C, leading to less Li/Ni mixing and oxygen vacancy. Meanwhile, the strong transitional metal(TM)-F bonds are helpful for enhancing de-/lithiation kinetics and limiting the lattice oxygen escape even at 4.5 V high-voltage. Their advantages synergistically endow the single-crystalline NCM85 cathode with a very high reversible capacity of 222.3 mAh g-1. A superior capacity retention of 91.3% is obtained after 500 times at 1 C in pouch-type full cells, and a prediction value of 75.3% is given after cycling for 5000 h. These findings are reckoned to expedite the exploitation and application of high-voltage single-crystalline Ni-rich cathodes for next-generation Li-ion batteries.展开更多
O3-type layered oxide cathodes for sodium-ion batteries are promising owing to high theoretical capacity and broad temperature adaptability,yet hindered by structural degradation and sluggish Na^(+)diffusion kinetics....O3-type layered oxide cathodes for sodium-ion batteries are promising owing to high theoretical capacity and broad temperature adaptability,yet hindered by structural degradation and sluggish Na^(+)diffusion kinetics.Herein,we present a sodium-deficient high-entropy layered oxide cathode(Na_(0.85)Ni_(0.3)Mn_(0.3)Fe_(0.1)Co_(0.15)Ti_(0.1)Cu_(0.05)B_(0.02)O_(2),denoted as Na0.85-HEO),combining sodium content optimization and high-entropy composition design.Incorporating six transition metals and light element boron creates a unique high-entropy configuration,effectively mitigating local lattice distortion and internal strain through chemical disorder effects,thereby enabling highly reversible phase transitions(O3-P3-O3)and smaller volume change(0.6A^(3))during the initial cycle.The sodium-deficient high-entropy design effectively increases the sodium interlayer spacing to 0.322 nm,facilitating the Na^(+)diffusion kinetics.Moreover,this high-entropy strategy enables the cathode to have a completely solid solution charge curve and significantly reduces the proportion of(O_(2))^(n-),thereby suppressing gas release during the cycling process.The resultant cathode demonstrates exceptional cyclability(80% capacity retention after 400 cycles at 100 mA g^(-1)in a full cell),and remarkable low-temperature performance(108.6 mAh g^(-1)at -40℃).This work guides the design of high-entropy electrode materials with tailored ionic transport channels for extreme-temperature energy storage applications.展开更多
ⅢThe superior adaptability of Prussian blue analogues(PBAs)in interacting with potassium ions has shifted research focus toward their potential application as cathodes of potassium-ion batteries(PIBs).The large inter...ⅢThe superior adaptability of Prussian blue analogues(PBAs)in interacting with potassium ions has shifted research focus toward their potential application as cathodes of potassium-ion batteries(PIBs).The large interstitial space formed between metal ions and–C≡N–in PBAs can accommodate large-radius K^(+).However,the rapid nucleation in the co-precipitation synthesis process of PBAs induces many lattice defects of[M(CN)_(6)]^(4-)vacancies(V_([M–C≡N])),interstitial and coordinated H_(2)O molecules,which will directly lead to performance degradation.Moreover,originating from various transition metal elements in low/high-spin electron configuration states,PBAs exhibit diverse electrochemical behaviors,such as low reaction kinetics of low-spin iron(Ⅱ),Jahn-Teller distortion and dissolution of manganese(Ⅲ),and electrochemical inertness of nickel(Ⅱ)and copper(Ⅱ).Here,we summarize recently reported structures and properties of PBAs,classifying them based on the types of transition metals(iron,cobalt,manganese,copper,nickel)employed.Advanced synthesis strategies,including control engineering of crystallinity based on H_(2)O molecules and V_([M–C≡N]),were discussed.Also,the approaches for enhancing the electrochemical performance of PBAs were highlighted.Finally,the challenges and prospects towards the future development of PBAs are put forward.The review is expected to provide technical and theoretical support for the design of high-performance PBAs.展开更多
In the realm of sodium-ion batteries(SIBs),Mn-based layered oxide cathodes have garnered considerable attention owing to their anionic redox reactions(ARRs).Compared to other types of popular sodium-ion cathodes,Mn-ba...In the realm of sodium-ion batteries(SIBs),Mn-based layered oxide cathodes have garnered considerable attention owing to their anionic redox reactions(ARRs).Compared to other types of popular sodium-ion cathodes,Mn-based layered oxide cathodes with ARRs exhibit outstanding specific capacity and energy density,making them promising for SIB applications.However,these cathodes still face some scientific challenges that need to be addressed.This review systematically summarizes the composition,structure,oxygen-redox mechanism,and performance of various types of Mn-based cathodes with ARRs,as well as the main scientific challenges they face,including sluggish ion diffusion,cationic migration,O_(2) release,and element dissolution.Currently,to resolve these challenges,efforts mainly focus on six aspects:synthesis methods,structural design,doped modification,electrolyte design,and surface engineering.Finally,this review provides new insights for future direction,encompassing both fundamental research,such as novel cathode types,interface optimization,and interdisciplinary research,and considerations from an industrialization perspective,including scalability,stability,and safety.展开更多
In pursuit of low cost and long life for lithium-ion batteries in electric vehicles,the most promising strategy is to replace the commercial LiCoO_(2)with a high-energy-density Ni-rich cathode.However,the irreversible...In pursuit of low cost and long life for lithium-ion batteries in electric vehicles,the most promising strategy is to replace the commercial LiCoO_(2)with a high-energy-density Ni-rich cathode.However,the irreversible redox couples induce rapid capacity decay,poor long-term cycling life,vast gas evolution,and unstable structure transformations of the Ni-rich cathode,limiting its practical applications.Element doping has been considered as the most promising strategy for addressing these issues.However,the relationships between element doping functions and redox chemistry still remain confused.To clarify this connection,this review places the dynamic evolution of redox couples(Li^(*),Ni^(2+)/Ni^(3+)/Ni^(4+)-e^(-),O^(2-)/O^(n-)/O_(2)-e^(-))as the tree trunk.The material structure,degradation mechanisms,and addressing element doping strategies are considered as the tree branches.This comprehensive summary aims to provide an overview of the current understanding and progress of Ni-rich cathode materials.In the last section,promising strategies based on element doping functions are provided to encourage the practical application of Ni-rich cathodes.These strategies also offer a new approach for the development of other intercalated electrode materials in Na and K-based battery systems.展开更多
High-performance aqueous zinc(Zn)-ion batteries(AZIBs)have emerged as one of the greatest favorable candidates for next-generation energy storage systems because of their low cost,sustainability,high safety,and eco-fr...High-performance aqueous zinc(Zn)-ion batteries(AZIBs)have emerged as one of the greatest favorable candidates for next-generation energy storage systems because of their low cost,sustainability,high safety,and eco-friendliness.In this report,we prepared magnesium vanadate(MgVO)-based nanostructures by a facile single-step solvothermal method with varying experimental reaction times(1,3,and 6 h)and investigated the effect of the reaction time on the morphology and layered structure for MgVO-based compounds.The newly prepared MgVO-1 h,MgVO-3 h and MgVO-6 h samples were used as cathode materials for AZIBs.Compared to the MgVO-1 h and MgVO-6 h cathodes,the MgVO-3 h cathode showed a higher specific capacity of 492.74 mA h g^(-1) at 1 A g^(-1) over 500 cycles and excellent rate behavior(291.58 mA h g^(-1) at 3.75 A g^(-1))with high cycling stability(116%)over 2000 cycles at 5 A g^(-1).Moreover,the MgVO-3 h electrode exhibited good electrochemical performance owing to its fast Zn-ion diffusion kinetics.Additionally,various ex-situ analyses confirmed that the MgVO-3 h cathode displayed excellent insertion/extraction of Zn^(2+)ions during charge and discharge processes.This study offers an efficient method for the synthesis of nanostructured MgVO-based cathode materials for high-performance AZIBs.展开更多
LiNixCoyMn_(2)O_(2)(NCM,x≥0.8,x+y+z=1)cathodes have attracted much attention due to their high specific capacity and low cost.However,severe anisotropic volume changes and oxygen evolution induced capacity decay and ...LiNixCoyMn_(2)O_(2)(NCM,x≥0.8,x+y+z=1)cathodes have attracted much attention due to their high specific capacity and low cost.However,severe anisotropic volume changes and oxygen evolution induced capacity decay and insecurity have hindered their commercial application at scale.In order to overcome these challenges,a kind of tantalum(Ta)doped nickel-rich cathode with reduced size and significantly increased number of primary particles is prepared by combining mechanical fusion with high temperature co-calcination.The elaborately designed micro-morphology of small and uniform primary particles effectively eliminates the local strain accumulation caused by the random orientation of primary particles.Moreover,the uniform distribution of small primary particles stabilizes the spherical secondary particles,thus effectively inhibiting the formation and extension of microcracks.In addition,the formed strong Ta-O bonds restrain the release of lattice oxygen,which greatly increases the structural stability and safety of NCM materials.Therefore,the cathode material with the designed primary particle morphology shows superior electrochemical performance.The 1 mol%Ta-modified cathode(defined as1%Ta-NCM)shows a capacity retention of 97.5%after 200 cycles at 1 C and a rate performance of 137.3 mAh g^(-1)at 5 C.This work presents promising approach to improve the structural stability and safety of nickel-rich NCM.展开更多
Metal fluoride materials with high theoretical capacities are considered the next generation of Li-free conversion cathodes.However,the inherently sluggish reaction kinetics of metal fluorides result in unsatisfactory...Metal fluoride materials with high theoretical capacities are considered the next generation of Li-free conversion cathodes.However,the inherently sluggish reaction kinetics of metal fluorides result in unsatisfactory electrochemical performance.In this study,CoF_(2)was combined with carbonaceous materials to obtain graphitic carbon-encapsulated CoF_(2)nanoparticles uniformly embedded in an interconnected N-doped carbon matrix(CoF_(2)@NC),significantly boosting the inert kinetics and electronic conductivity.The CoF_(2)@NC nanocomposites exhibited a notable reversible capacity of 352.0 mAh·g^(-1)at 0.2 A·g^(-1).Notably,it maintained superior long-term cycling stability even at a high current density of 2 A·g^(-1),with a capacity of 235.5 mAh·g^(-1)after 1200 cycles,evidently exceeding that of commercially available CoF_(2)electrodes.Kinetic analysis indicated that the enhanced electrochemical performance originated from the increased contribution of capacitive effects.Furthermore,in-situ electrochemical impedance spectroscopy(EIS)results verify that the improved cycling performance is associated with the enhanced interfacial stability of CoF_(2)@NC.This research not only proposes a solution for the challenges of conversion cathodes in lithium-ion batteries,but also offers novel synthesis strategies for designing high-energy metal fluoride materials.展开更多
Mn-based layered oxides are widely recognized as cathode materials for potassium-ion batteries(KIBs)due to their high specific capacity derived from their low molar mass.However,the structural instability caused by th...Mn-based layered oxides are widely recognized as cathode materials for potassium-ion batteries(KIBs)due to their high specific capacity derived from their low molar mass.However,the structural instability caused by the Jahn-Teller effect of Mn^(3+)and the large ionic radius of K+results in poor electrochemical performance.Herein,we propose an effective structural stabilization strategy for P2-type Mn-based layered oxide cathodes of KIBs through Li-incorporation into the transition metal layer.Using the firstprinciples calculations and experiments,we demonstrate that the P2-K_(0.48)[Li_(0.1)Mn_(0.9)]O_(2)(P2-KLMO)delivers improved electrochemical performance,specific capacity and average discharge voltage of~124.4 m A h g^(-1)and~2.7 V(vs.K^(+)/K)at 0.05C(1C=260 mA g^(-1)),outperforming P2-K_(0.5)MnO_(2).Operando X-ray diffraction analysis confirms the P2-OP4 phase transition and Mn^(3+)-induced Jahn-Teller distortion are significantly suppressed in P2-KLMO.These improvements are attributed to the lithium introduction into transition metal layers,leading to strengthened structural stability and enhanced K+diffusion kinetics.Moreover,synthetic accessibility through the conventional solid-state method provides an additional advantage for practical application of Li-incorporated Mn-based P2-type cathodes in KIBs.We believe our study offers a simple yet effective strategy for designing highperformance and practical cathode materials for KIBs.展开更多
The effects of synthesis conditions,especially the heating rate,on the reaction kinetics of Ni-rich cathodes were systematically studied.The growth rate of Ni-rich oxide increases continuously as the heating rate incr...The effects of synthesis conditions,especially the heating rate,on the reaction kinetics of Ni-rich cathodes were systematically studied.The growth rate of Ni-rich oxide increases continuously as the heating rate increases.Ab initio molecular dynamics simulations demonstrate that a high heating rate induces anabatic oscillations,indicating a decrease in thermodynamic stability and a tendency for the crystal surface to undergo reconstruction.The presence of an intermediate phase at the grain boundary amplifies atomic migration-induced interface fusion and consequently augments crystal growth kinetics.However,the excessively high heating rate aggravates the Li+/Ni2+mixing in the Ni-rich cathode.The single-crystal Ni-rich cathode exhibits enhanced structural/thermal stability but a decreased specific capacity and rate performance compared with its polycrystalline counterpart.展开更多
Within the framework of carbon neutrality,lithium-ion batteries(LIBs)are progressively booming along with the growing utilization of green and clean energy.However,the extensive application of LIBs with limited lifesp...Within the framework of carbon neutrality,lithium-ion batteries(LIBs)are progressively booming along with the growing utilization of green and clean energy.However,the extensive application of LIBs with limited lifespan has brought about a significant recycling dilemma.The traditional hydrometallurgical or pyrometallurgical strategies are not capable to maximize the output value of spent LIBs and minimize the potential environmental hazards.Herein,to alternate the tedious and polluting treatment processes,we propose a high-temperature molten-salt strategy to directly regenerate spent cathodes of LIBs,which can also overcome the barrier of the incomplete defects'restoration with previous low-temperature molten salts.The high-energy and stable medium environment ensures a more thorough and efficient relithiation reaction,and simultaneously provides sufficient driving force for atomic rearrangement and grains secondary growth.In consequence,the regenerated ternary cathode(R-NCM)exhibits significantly enhanced structural stability that effectively suppresses the occurrence of cracks and harmful side reactions.The R-NCM delivers excellent cycling stability,retaining 81.2%of its capacity after 200 cycles at 1 C.This technique further optimizes the traditional eutectic molten-salt approach,broadening its applicability and improving regenerated cathode performance across a wider range of conditions.展开更多
基金supported by the Natural Science Foundation of Tianjin-Science and the Technology Correspondent Project(19YFSLQY00070)the State Key Laboratory of Organic-Inorganic Composites(oic-201901004)+1 种基金the National Natural Science Foundation of China(21676070)Hebei University of Science and Technology(20544401D,20314401D)。
文摘Aqueous zinc-ion batteries(ZIBs)have got wide attention with the increasing demands for energy resource recently.It has a number of merits compared with lithium-ion batteries,such as enhanced safety,low cost and environmental friendliness.Vanadium-based materials have been developed to serve as the cathodes of ZIBs for many years.But there are also some challenges to construct high performance ZIBs in the future.Herein,we reviewed the research progress of vanadium-based cathodes and discussed the energy storage mechanisms in ZIBs.In addition,we summarized the major challenges faced by vanadium-based cathodes and the corresponding ways to improve electrochemical performance of ZIBs.Finally,some excellent vanadium-based cathodes are summarized to pave the way for future research in ZIBs.
基金supported by the National Natural Science Foundation of China (Nos. U1910210, U1810204 and 22004122)Research Foundation for the Returned Overseas in Shanxi Provence (No. 2020-048)the Central Guidance on Local Science and Technology Development Fund of Shanxi Province (No. YDZJSX2021A021)。
文摘As an emerging energy storage device with high-safety aqueous electrolytes, low-cost, environmental benignity and large-reserves, the rechargeable aqueous zinc-ion batteries(AZIBs) have attracted more and more attention. Vanadium-based compounds are also supposed as the potential candidate cathode materials for AZIBs due to their wide variety of phases, variable crystal structures and high theoretical capacity. In this review, the recent progress in the development of vanadium-based materials was summarized,and the relationship between the crystal structure types of active materials and Zn-ion transport mechanism was highlighted. During the charge-discharge process, the different electrostatic repulsion between the cations of vanadium-based compounds with different crystal structures and Zn^(2+)results in a variety of the Zn-ion storage mechanisms, which can be significant guidance for designing the advanced batteryelectrode materials for AZIBs. Furthermore, other factors associated with the storage mechanisms, such as electrolyte components and electrode morphology, are discussed. Finally, the strategies to improve the electrical conductivity, inhibit the dissolution and stabilize the crystal structure of vanadium-based compounds are proposed and the future prospects for developing high-energy-density AZIBs are presented.
基金financially supported by the National Natural Science Foundation of China(NSFC)(52274295)the Natural Science Foundation of Hebei Province(E2021501029)+3 种基金the Fundamental Research Funds for the Central Universities(N2423051,N2423053,N2302016,N2423019,N2323013,N2423005)the Science and Technology Project of Hebei Education Department(QN2024238)the Basic Research Program Project of Shijiazhuang City for Universities Stationed in Hebei Province(241790937A)the Science and Technology Project of Qinhuangdao City in 2023.
文摘Mn-based layered oxides(KMO)have emerged as one of the promising low-cost cathodes for potassiumion batteries(PIBs).However,due to the multiple-phase transitions and the distortion in the MnO6structure induced by the Jahn-Teller(JT)effect associated with Mn-ion,the cathode exhibits poor structural stability.Herein,we propose a strategy to enhance structural stability by introducing robust metal-oxygen(M-O)bonds,which can realize the pinning effect to constrain the distortion in the transition metal(TM)layer.Concurrently,all the elements employed have exceptionally high crustal abundance.As a proof of concept,the designed K_(0.5)Mn_(0.9)Mg_(0.025)Ti_(0.025)Al_(0.05)O_(2)cathode exhibited a discharge capacity of approximately 100 mA h g^(-1)at 20 mA g^(-1)with 79%capacity retention over 50 cycles,and 73%capacity retention over 200 cycles at 200 mA g^(-1),showcased much better battery performance than the designed cathode with less robust M-O bonds.The properties of the formed M-O bonds were investigated using theoretical calculations.The enhanced dynamics,mitigated JT effect,and improved structural stability were elucidated through the in-situ X-ray diffractometer(XRD),in-situ electrochemical impedance spectroscopy(EIS)(and distribution of relaxation times(DRT)method),and ex-situ X-ray absorption fine structure(XAFS)tests.This study holds substantial reference value for the future design of costeffective Mn-based layered cathodes for PIBs.
基金supported by the Hainan Province Science and Technology Special Fund(ZDYF2021SHFZ232,ZDYF2023GXJS022)the Hainan Province Postdoctoral Science Foundation(300333)the National Natural Science Foundation of China(21203008,21975025,12274025,22372008)。
文摘Sulfide-based all-solid-state lithium batteries suffer from electrochemo-mechanical damage to Ni-rich oxide-based cathode active materials(CAMs),primarily caused by severe volume changes,results in significant stress and strain,causes micro-cracks and interfacial contact loss at potentials>4.3 V(vs.Li/Li^(+)).Quantifying micro-cracks and voids in CAMs can reveal the degradation mechanisms of Ni-rich oxidebased cathodes during electrochemical cycling.Nonetheless,the origin of electrochemical-mechanical damage remains unclear.Herein,We have developed a multifunctional PEG-based soft buffer layer(SBL)on the surface of carbon black(CB).This layer functions as a percolation network in the single crystal LiNi_(0.83)Co_(0.07)Mn_(0.1)O_(2)and Li_(6)PS_(5)Cl composite cathode layer,ensuring superior ionic conductivity,reducing void formation and particle cracking,and promoting uniform utilization of the cathode active material in all-solid-state lithium batteries(ASSLBs).High-angle annular dark-field STEM combined with nanoscale X-ray holo-tomography and plasma-focused ion beam scanning electron microscopy confirmed that the PEG-based SBL mitigated strain induced by reaction heterogeneity in the cathode.This strain produces lattice stretches,distortions,and curved transition metal oxide layers near the surface,contributing to structural degradation at elevated voltages.Consequently,ASSLBs with a LiNi_(0.83)Co_(0.07)Mn_(0.1)O_(2)cathode containing LCCB-10(CB/PEG mass ratio:100/10)demonstrate a high areal capacity(2.53 mAh g^(-1)/0.32 mA g^(-1))and remarkable rate capability(0.58 mAh g^(-1)at 1.4 mA g^(-1)),with88%capacity retention over 1000 cycles.
基金supported by the National Key R&D Program of China(2022YFB3803501)the National Natural Science Foundation of China(22179008,22209156)+5 种基金support from the Beijing Nova Program(20230484241)support from the China Postdoctoral Science Foundation(2024M754084)the Postdoctoral Fellowship Program of CPSF(GZB20230931)support from beamline BL08U1A of Shanghai Synchrotron Radiation Facility(2024-SSRF-PT-506950)beamline 1W1B of the Beijing Synchrotron Radiation Facility(2021-BEPC-PT-006276)support from Initial Energy Science&Technology Co.,Ltd(IEST)。
文摘The implementation of ultrahigh-Ni cathodes in high-energy lithium-ion batteries(LIBs)is constrained by significant structural and interfacial degradation during cycling.In this study,doping-induced surface restructuring in ultrahigh-nickel cathode materials is rapidly facilitated through an ultrafast Joule heating method.Density functional theory(DFT)calculations,synchrotron X-ray absorption spectroscopy(XAS),and single-particle force test confirmed the establishment of a stable crystal framework and lattice oxygen,which mitigated H2-H3 phase transitions and improved structural reversibility.Additionally,the Sc doping process exhibits a pinning effect on the grain boundaries,as shown by scanning transmission electron microscopy(STEM),enhancing Li~+diffusion kinetics and decreasing mechanical strain during cycling.The in situ development of a cation-mixing layer at grain boundaries also creates a robust cathode/electrolyte interphase,effectively reducing interfacial parasitic reactions and transition metal dissolution,as validated by STEM and time-of-flight secondary ion mass spectrometry(TOF-SIMS).These synergistic modifications reduce particle cracking and surface/interface degradation,leading to enhanced rate capability,structural integrity,and thermal stability.Consequently,the optimized Sc-modified ultrahigh-Ni cathode(Sc-1)exhibits 93.99%capacity retention after 100 cycles at 1 C(25℃)and87.06%capacity retention after 100 cycles at 1 C(50℃),indicating excellent cycling and thermal stability.By presenting a one-step multifunctional modification approach,this research delivers an extensive analysis of the mechanisms governing the structure,microstructure,and interface properties of nickel-rich layered cathode materials(NCMs).These results underscore the potential of ultrahigh-Ni cathodes as viable candidates for advanced lithium-ion batteries(LIBs)in next-generation electric vehicles(EVs).
基金supported by the National Key Research and Development Program of China(Grant No.2022YFB2502200)the National Natural Science Foundation of China(Grant Nos.52325207,22239003,and 22393904).
文摘Lithium-rich manganese-based cathodes(LRMs)have garnered significant attention as promising candidates for highenergy-density batteries due to their exceptional specific capacity exceeding 300 mAh/g,achieved through synergistic anionic and cationic redox reactions.However,these materials face challenges including oxygen release-induced structural degradation and consequent capacity fading.To address these issues,strategies such as surface modification and bulk phase engineering have been explored.In this study,we developed a facile and cost-effective quenching approach that simultaneously modifies both surface and bulk characteristics.Multi-scale characterization and computational analysis reveal that rapid cooling partially preserves the high-temperature disordered phase in the bulk structure,thereby enhancing the structural stability.Concurrently,Li^(+)/H^(+)exchange at the surface forms a robust rock-salt/spinel passivation layer,effectively suppressing oxygen evolution and mitigating interfacial side reactions.This dual modification strategy demonstrates a synergistic stabilization effect.The enhanced oxygen redox activity coexists with the improved structural integrity,leading to superior electrochemical performance.The optimized cathode delivers an initial discharge capacity approaching 307.14 mAh/g at 0.1 C and remarkable cycling stability with 94.12%capacity retention after 200 cycles at 1 C.This study presents a straightforward and economical strategy for concurrent surface–bulk modification,offering valuable insights for designing high-capacity LRM cathodes with extended cycle life.
基金supported by the National Natural Science Foundation of China(22379121)the Shenzhen Foundation Research Fund(JCYJ20210324104412034)+1 种基金the Fundamental Research Funds for the Central Universities(G2024KY05103)the“Scientists+Engineers”Team in Qinchuangyuan of Shaanxi Province(2024QCY-KXJ-023)。
文摘Ni-rich layered oxide cathode materials such as LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NCM811)face poor interfacial stability and serious side reactions with sulfide solid-state electrolytes.This problem is thought to be exacerbated by the gradually accumulated basicity of the surface with the Ni content increasing.Herein,the acidic Li_(3)PO_(4)coating layer on NCM811 particles is introduced by ball-milling approach to neutralize the basicity and aggrandize the interfacial stability.The tailored surface structure and components of NCM811 not only suppress the direct contact of cathode particles with sulfide solid-state electrolyte,but also facilitate electrochemical dynamics by driving the Li+migration across the interface and promoting the electron exchange.Thus,cells with Li_(3)PO_(4)coating layer yield 101.3 mAh g^(-1)specific capacity at 2.0 C and highly reversed discharging capacity after suffering from harsh work conditions.Additionally,the stable coating layer broadens the electrochemical windows of cells,delivering long cycle stability(>100 cycles 0.5 C).This contribution highlights the importance of basicity regulation of Ni-rich layered oxide cathode and offers a low-cost and effective approach to design the interfacial structures for the development of all solid-state batteries.
基金supported by the Natural Science Research Project of the Education Department of Guizhou Province(No.QJJ[2022]001)。
文摘Cathode materials with excellent performance are a key to exploiting aqueous zinc ion batteries.In this study,we developed a cathode material for aqueous zinc ion batteries using an in situ anion–cation pre-intercalation strategy with a metal–organic framework.In situ doping of S and Zn in a vanadium-based metal–organic framework structure forms a Zn–S pre-intercalated vanadium oxide((Zn,S)VO)composite.The combination of the additional Zn^(2+)storage sites with pseudocapacitive behavior on the amorphous surface of the enriched oxygen defects and the enhancement of the structural toughness by strong ionic bonding together the unique nanostructure of the nanochains by the process of‘‘oriented attachment’’led to the preparation of the high-performance(Zn,S)VO composite.The results show that the(Zn,S)VO electrode has a capacity of 602.40 mAh·g^(-1)at 0.1 A·g^(-1),an initial discharge capacity of 300.60 mAh·g^(-1)at 10.0 A·g^(-1),and a capacity retention rate of 99.93%after 3,500 cycles.Using the gel electrolyte,the capacity of(Zn,S)VO electrode is 233.15 and 650.93 mAh·g^(-1)at 0.2 A·g^(-1)in-20 and 60°C environments,respectively.Meanwhile,the(Zn,S)VO flexible batteries perform well in harsh environments.
基金financially supported by the National Natura Science Foundation of China(51108455,52106264)Civil Aviation Safety Capacity Building Fund(ADSA2022026)+2 种基金Liaoning Revitalization Talents Program(XLYC2018013)Liaoning Province AppliedFoundation Research Program Project(2023JH2/101300215)Unveiled the List of Local Service Projects from Education Department of Liaoning Province(JYTMS20230227)。
文摘Lithium-rich manganese-based cathode materials(LMCMs)have garnered significant attention in power lithium-ion batteries(LIBs)and energy storage systems due to their superior energy density and costeffectiveness.However,the commercial application of LMCMs is hindered by challenges such as low initial coulombic efficiency,severe voltage decay,and inferior cycling performance.Surface structure degradation has been confirmed as a critical factor contributing to the electrochemical performance deterioration of LMCMs.Herein,we review the recent progress in surface engineering of LMCMs towards next-generation LIBs.Besides classical surface coating,mechanism and functions of surface oxygen vacancies for greatly boosting the electrochemical performance of LMCMs are also summarized in detail.Finally,we discuss the emerging trends and propose future research directions of surface engineering of LMCMs for achieving more efficient improvements.This work underscores the indispensable potential of surface engineering in enhancing the surface structure stability and electrochemical performance of LMCMs as promising candidates for next-generation high-energy LIBs.Synergistic integration of surface engineering and single-crystal technology will be a promising modification strategy for significantly promoting the commercialization of LMCMs,and the corresponding synergistic mechanisms urgently need to be studied for rationally designing high-performance electrodes.More efforts will be devoted to understand the surface engineering of LMCMs for the large-scale application of high-energy LIBs.
基金supported by the National Natural Science Foundation of China(U22A20429 and 22308103)Shanghai Pilot Program for Basic Research(22TQ1400100-13)+2 种基金Postdoctoral Fellowship Program of CPSF(GZB20230214)China Postdoctoral Science Foundation(2023M731083)the Fundamental Research Funds for the Central Universities.
文摘Developing cost-effective single-crystalline Ni-rich Co-poor cathodes operating at high-voltage is one of the most important ways to achieve higher energy Li-ion batteries. However, the Li/O loss and Li/Ni mixing under high-temperature lithiation result in electrochemical kinetic hysteresis and structural instability. Herein, we report a highly-ordered single-crystalline LiNi0.85Co0.05Mn0.10O2(NCM85) cathode by doping K+and F-ions. To be specific, the K-ion as a fluxing agent can remarkably decrease the solid-state lithiation temperature by ~30°C, leading to less Li/Ni mixing and oxygen vacancy. Meanwhile, the strong transitional metal(TM)-F bonds are helpful for enhancing de-/lithiation kinetics and limiting the lattice oxygen escape even at 4.5 V high-voltage. Their advantages synergistically endow the single-crystalline NCM85 cathode with a very high reversible capacity of 222.3 mAh g-1. A superior capacity retention of 91.3% is obtained after 500 times at 1 C in pouch-type full cells, and a prediction value of 75.3% is given after cycling for 5000 h. These findings are reckoned to expedite the exploitation and application of high-voltage single-crystalline Ni-rich cathodes for next-generation Li-ion batteries.
基金financially supported by the National Natural Science Foundation of China(No.52071073,52177208,and 52171202)the Hebei Province“333 talent project”(No.C20221012)+2 种基金the Science and Technology Project of Hebei Education Department(BJK2023005)the Fundamental Research Funds for the Central Universities(2024GFZD002)the Natural Science Foundation of Hebei Province(E2024501015)。
文摘O3-type layered oxide cathodes for sodium-ion batteries are promising owing to high theoretical capacity and broad temperature adaptability,yet hindered by structural degradation and sluggish Na^(+)diffusion kinetics.Herein,we present a sodium-deficient high-entropy layered oxide cathode(Na_(0.85)Ni_(0.3)Mn_(0.3)Fe_(0.1)Co_(0.15)Ti_(0.1)Cu_(0.05)B_(0.02)O_(2),denoted as Na0.85-HEO),combining sodium content optimization and high-entropy composition design.Incorporating six transition metals and light element boron creates a unique high-entropy configuration,effectively mitigating local lattice distortion and internal strain through chemical disorder effects,thereby enabling highly reversible phase transitions(O3-P3-O3)and smaller volume change(0.6A^(3))during the initial cycle.The sodium-deficient high-entropy design effectively increases the sodium interlayer spacing to 0.322 nm,facilitating the Na^(+)diffusion kinetics.Moreover,this high-entropy strategy enables the cathode to have a completely solid solution charge curve and significantly reduces the proportion of(O_(2))^(n-),thereby suppressing gas release during the cycling process.The resultant cathode demonstrates exceptional cyclability(80% capacity retention after 400 cycles at 100 mA g^(-1)in a full cell),and remarkable low-temperature performance(108.6 mAh g^(-1)at -40℃).This work guides the design of high-entropy electrode materials with tailored ionic transport channels for extreme-temperature energy storage applications.
基金financially supported by research grants from Innovative Research Group Project of National Natural Science Foundation of China(No.52021004)National Key Research and Development Program of China(2022YFB3803300)+2 种基金National Natural Science Foundation of China(62474026 and 62074022)Natural Science Foundation of Chongqing(CSTB2024NSCQ-MSX1215,cstc2021jcyj-jqX0015 and CSTB2022NSCQ-MSX1183)the Youth Talent Support Program of Chongqing(CQYC2021059206).
文摘ⅢThe superior adaptability of Prussian blue analogues(PBAs)in interacting with potassium ions has shifted research focus toward their potential application as cathodes of potassium-ion batteries(PIBs).The large interstitial space formed between metal ions and–C≡N–in PBAs can accommodate large-radius K^(+).However,the rapid nucleation in the co-precipitation synthesis process of PBAs induces many lattice defects of[M(CN)_(6)]^(4-)vacancies(V_([M–C≡N])),interstitial and coordinated H_(2)O molecules,which will directly lead to performance degradation.Moreover,originating from various transition metal elements in low/high-spin electron configuration states,PBAs exhibit diverse electrochemical behaviors,such as low reaction kinetics of low-spin iron(Ⅱ),Jahn-Teller distortion and dissolution of manganese(Ⅲ),and electrochemical inertness of nickel(Ⅱ)and copper(Ⅱ).Here,we summarize recently reported structures and properties of PBAs,classifying them based on the types of transition metals(iron,cobalt,manganese,copper,nickel)employed.Advanced synthesis strategies,including control engineering of crystallinity based on H_(2)O molecules and V_([M–C≡N]),were discussed.Also,the approaches for enhancing the electrochemical performance of PBAs were highlighted.Finally,the challenges and prospects towards the future development of PBAs are put forward.The review is expected to provide technical and theoretical support for the design of high-performance PBAs.
基金National Key Research and Development Program of China,Grant/Award Number:2022YFB2502000National Natural Science Foundation of China,Grant/Award Number:52207244。
文摘In the realm of sodium-ion batteries(SIBs),Mn-based layered oxide cathodes have garnered considerable attention owing to their anionic redox reactions(ARRs).Compared to other types of popular sodium-ion cathodes,Mn-based layered oxide cathodes with ARRs exhibit outstanding specific capacity and energy density,making them promising for SIB applications.However,these cathodes still face some scientific challenges that need to be addressed.This review systematically summarizes the composition,structure,oxygen-redox mechanism,and performance of various types of Mn-based cathodes with ARRs,as well as the main scientific challenges they face,including sluggish ion diffusion,cationic migration,O_(2) release,and element dissolution.Currently,to resolve these challenges,efforts mainly focus on six aspects:synthesis methods,structural design,doped modification,electrolyte design,and surface engineering.Finally,this review provides new insights for future direction,encompassing both fundamental research,such as novel cathode types,interface optimization,and interdisciplinary research,and considerations from an industrialization perspective,including scalability,stability,and safety.
基金supported by the National Natural Science Foundation of China(22209055)the China Postdoctoral Science Foundation(2022M721330)+2 种基金the Foshan Postdoctoral Science Foundation(X221081MS210)the Innovation Team of Universities of Guangdong Province(2022KCXTD030)the“Targeted Technology Innovation Initiative”Project at the Foshan National Institute of Innovation(JBGS2024002)。
文摘In pursuit of low cost and long life for lithium-ion batteries in electric vehicles,the most promising strategy is to replace the commercial LiCoO_(2)with a high-energy-density Ni-rich cathode.However,the irreversible redox couples induce rapid capacity decay,poor long-term cycling life,vast gas evolution,and unstable structure transformations of the Ni-rich cathode,limiting its practical applications.Element doping has been considered as the most promising strategy for addressing these issues.However,the relationships between element doping functions and redox chemistry still remain confused.To clarify this connection,this review places the dynamic evolution of redox couples(Li^(*),Ni^(2+)/Ni^(3+)/Ni^(4+)-e^(-),O^(2-)/O^(n-)/O_(2)-e^(-))as the tree trunk.The material structure,degradation mechanisms,and addressing element doping strategies are considered as the tree branches.This comprehensive summary aims to provide an overview of the current understanding and progress of Ni-rich cathode materials.In the last section,promising strategies based on element doping functions are provided to encourage the practical application of Ni-rich cathodes.These strategies also offer a new approach for the development of other intercalated electrode materials in Na and K-based battery systems.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIP)(No.2018R1A6A1A03025708).
文摘High-performance aqueous zinc(Zn)-ion batteries(AZIBs)have emerged as one of the greatest favorable candidates for next-generation energy storage systems because of their low cost,sustainability,high safety,and eco-friendliness.In this report,we prepared magnesium vanadate(MgVO)-based nanostructures by a facile single-step solvothermal method with varying experimental reaction times(1,3,and 6 h)and investigated the effect of the reaction time on the morphology and layered structure for MgVO-based compounds.The newly prepared MgVO-1 h,MgVO-3 h and MgVO-6 h samples were used as cathode materials for AZIBs.Compared to the MgVO-1 h and MgVO-6 h cathodes,the MgVO-3 h cathode showed a higher specific capacity of 492.74 mA h g^(-1) at 1 A g^(-1) over 500 cycles and excellent rate behavior(291.58 mA h g^(-1) at 3.75 A g^(-1))with high cycling stability(116%)over 2000 cycles at 5 A g^(-1).Moreover,the MgVO-3 h electrode exhibited good electrochemical performance owing to its fast Zn-ion diffusion kinetics.Additionally,various ex-situ analyses confirmed that the MgVO-3 h cathode displayed excellent insertion/extraction of Zn^(2+)ions during charge and discharge processes.This study offers an efficient method for the synthesis of nanostructured MgVO-based cathode materials for high-performance AZIBs.
基金financial support provided by the National Natural Science Foundation of China(52271201)the Science and Technology Department of Sichuan Province(2025NSFTD0005,2022YFG0100,2022ZYD0045)。
文摘LiNixCoyMn_(2)O_(2)(NCM,x≥0.8,x+y+z=1)cathodes have attracted much attention due to their high specific capacity and low cost.However,severe anisotropic volume changes and oxygen evolution induced capacity decay and insecurity have hindered their commercial application at scale.In order to overcome these challenges,a kind of tantalum(Ta)doped nickel-rich cathode with reduced size and significantly increased number of primary particles is prepared by combining mechanical fusion with high temperature co-calcination.The elaborately designed micro-morphology of small and uniform primary particles effectively eliminates the local strain accumulation caused by the random orientation of primary particles.Moreover,the uniform distribution of small primary particles stabilizes the spherical secondary particles,thus effectively inhibiting the formation and extension of microcracks.In addition,the formed strong Ta-O bonds restrain the release of lattice oxygen,which greatly increases the structural stability and safety of NCM materials.Therefore,the cathode material with the designed primary particle morphology shows superior electrochemical performance.The 1 mol%Ta-modified cathode(defined as1%Ta-NCM)shows a capacity retention of 97.5%after 200 cycles at 1 C and a rate performance of 137.3 mAh g^(-1)at 5 C.This work presents promising approach to improve the structural stability and safety of nickel-rich NCM.
基金supported by the National Natural Science Foundation of China(Nos.22279101,22172117 and 52072298)Foshan Science and Technology Innovation Team Project(No.1920001004098)+1 种基金Scientific Research Program Funded by Education Department of Shaanxi Provincial Government(No.22JP056)the Natural Science Basic Research Program of Shaanxi(No.2024JC-YBQN-0141).
文摘Metal fluoride materials with high theoretical capacities are considered the next generation of Li-free conversion cathodes.However,the inherently sluggish reaction kinetics of metal fluorides result in unsatisfactory electrochemical performance.In this study,CoF_(2)was combined with carbonaceous materials to obtain graphitic carbon-encapsulated CoF_(2)nanoparticles uniformly embedded in an interconnected N-doped carbon matrix(CoF_(2)@NC),significantly boosting the inert kinetics and electronic conductivity.The CoF_(2)@NC nanocomposites exhibited a notable reversible capacity of 352.0 mAh·g^(-1)at 0.2 A·g^(-1).Notably,it maintained superior long-term cycling stability even at a high current density of 2 A·g^(-1),with a capacity of 235.5 mAh·g^(-1)after 1200 cycles,evidently exceeding that of commercially available CoF_(2)electrodes.Kinetic analysis indicated that the enhanced electrochemical performance originated from the increased contribution of capacitive effects.Furthermore,in-situ electrochemical impedance spectroscopy(EIS)results verify that the improved cycling performance is associated with the enhanced interfacial stability of CoF_(2)@NC.This research not only proposes a solution for the challenges of conversion cathodes in lithium-ion batteries,but also offers novel synthesis strategies for designing high-energy metal fluoride materials.
基金supported by the National Research Foundation of Korea funded by the Ministry of Science and ICT of Korea(RS-2024-00408156)。
文摘Mn-based layered oxides are widely recognized as cathode materials for potassium-ion batteries(KIBs)due to their high specific capacity derived from their low molar mass.However,the structural instability caused by the Jahn-Teller effect of Mn^(3+)and the large ionic radius of K+results in poor electrochemical performance.Herein,we propose an effective structural stabilization strategy for P2-type Mn-based layered oxide cathodes of KIBs through Li-incorporation into the transition metal layer.Using the firstprinciples calculations and experiments,we demonstrate that the P2-K_(0.48)[Li_(0.1)Mn_(0.9)]O_(2)(P2-KLMO)delivers improved electrochemical performance,specific capacity and average discharge voltage of~124.4 m A h g^(-1)and~2.7 V(vs.K^(+)/K)at 0.05C(1C=260 mA g^(-1)),outperforming P2-K_(0.5)MnO_(2).Operando X-ray diffraction analysis confirms the P2-OP4 phase transition and Mn^(3+)-induced Jahn-Teller distortion are significantly suppressed in P2-KLMO.These improvements are attributed to the lithium introduction into transition metal layers,leading to strengthened structural stability and enhanced K+diffusion kinetics.Moreover,synthetic accessibility through the conventional solid-state method provides an additional advantage for practical application of Li-incorporated Mn-based P2-type cathodes in KIBs.We believe our study offers a simple yet effective strategy for designing highperformance and practical cathode materials for KIBs.
基金funded by the National Natural Science Foundation of China(No.22379052)Taishan Scholars of Shandong Province,China(No.tsqnz20221143)。
文摘The effects of synthesis conditions,especially the heating rate,on the reaction kinetics of Ni-rich cathodes were systematically studied.The growth rate of Ni-rich oxide increases continuously as the heating rate increases.Ab initio molecular dynamics simulations demonstrate that a high heating rate induces anabatic oscillations,indicating a decrease in thermodynamic stability and a tendency for the crystal surface to undergo reconstruction.The presence of an intermediate phase at the grain boundary amplifies atomic migration-induced interface fusion and consequently augments crystal growth kinetics.However,the excessively high heating rate aggravates the Li+/Ni2+mixing in the Ni-rich cathode.The single-crystal Ni-rich cathode exhibits enhanced structural/thermal stability but a decreased specific capacity and rate performance compared with its polycrystalline counterpart.
基金support by National Natural Science Foundation of China(22379166)Natural Science Foundation for Distinguished Young Scholars of Hunan Province(2022JJ10089)Central South University Innovation-Driven Research Programme(2023CXQD034).
文摘Within the framework of carbon neutrality,lithium-ion batteries(LIBs)are progressively booming along with the growing utilization of green and clean energy.However,the extensive application of LIBs with limited lifespan has brought about a significant recycling dilemma.The traditional hydrometallurgical or pyrometallurgical strategies are not capable to maximize the output value of spent LIBs and minimize the potential environmental hazards.Herein,to alternate the tedious and polluting treatment processes,we propose a high-temperature molten-salt strategy to directly regenerate spent cathodes of LIBs,which can also overcome the barrier of the incomplete defects'restoration with previous low-temperature molten salts.The high-energy and stable medium environment ensures a more thorough and efficient relithiation reaction,and simultaneously provides sufficient driving force for atomic rearrangement and grains secondary growth.In consequence,the regenerated ternary cathode(R-NCM)exhibits significantly enhanced structural stability that effectively suppresses the occurrence of cracks and harmful side reactions.The R-NCM delivers excellent cycling stability,retaining 81.2%of its capacity after 200 cycles at 1 C.This technique further optimizes the traditional eutectic molten-salt approach,broadening its applicability and improving regenerated cathode performance across a wider range of conditions.
