Aqueous-electrolyte-based zinc-ion batteries(ZIBs),which have significant advantages over other batteries,including low cost,high safety,high ionic conductivity,and a natural abundance of zinc,have been regarded as a ...Aqueous-electrolyte-based zinc-ion batteries(ZIBs),which have significant advantages over other batteries,including low cost,high safety,high ionic conductivity,and a natural abundance of zinc,have been regarded as a potential alternative to lithium-ion batteries(LIBs).ZIBs still face some critical challenges,however,especially for building a reversible zinc anode.To address the reversibility of zinc anode,great efforts have been made on intrinsic anode engineering and anode interface modification.Less attention has been devoted to the electrolyte additives,however,which could not only significantly improve the reversibility of zinc anode,but also determine the viability and overall performance of ZIBs.This review aims to provide an overview of the two main functions of electrolyte additives,followed by details on six reasons why additives might improve the performance of ZIBs from the perspectives of creating new layers and regulating current plating/stripping processes.Furthermore,the remaining difficulties and potential directions for additives in aqueous ZIBs are also highlighted.展开更多
The addition of complexing agents to the electrolyte has been shown to be an effective method to enhance the discharge performance of magnesium-air batteries.In this work,four complexing agents:citric acid(CIT),salicy...The addition of complexing agents to the electrolyte has been shown to be an effective method to enhance the discharge performance of magnesium-air batteries.In this work,four complexing agents:citric acid(CIT),salicylic acid(SAL),2,6-dihydroxybenzoic acid(2,6-DHB),and 5-sulfoisophthalic acid(5-sulfoSAL)were selected as potential candidates.Through electrochemical tests,full-cell discharge experiments,and physicochemical characterization,the impact of these complexing agents on the discharge performance of magnesium-air batteries using AZ31 alloy as the anode material was investigated.The results demonstrated that the four complexing agents increased the discharge voltage of the batteries.Notably,SAL could significantly improve the anodic efficiency and the discharge specific capacity,achieving an anodic efficiency of 60.3%and a specific capacity of 1358.3 mA·h/g at a discharge current density of 10 mA/cm^(2).展开更多
Unstable Zn interface caused by rampant dendrite growth and parasitic side reactions always hinders the practical application of aqueous zinc metal batteries(AZMBs),Herein,tyrosine(Tyr)with high molecular polarity was...Unstable Zn interface caused by rampant dendrite growth and parasitic side reactions always hinders the practical application of aqueous zinc metal batteries(AZMBs),Herein,tyrosine(Tyr)with high molecular polarity was introduced into aqueous electrolyte to modulate the interfacial electrochemistry of Zn anode.In AZMBs,the positively charged side of Tyr can be well adsorbed on the surface of Zn anode to form a water-poor layer,and the exposed carboxylate side can be easily coordinated with Zn^(2+),favoring inducing uniform plating of Zn^(2+)and inhibiting the occurrence of water-induced side reactions.These in turn enable the achievement of highly stable Zn anode.Accordingly,the Zn anodes achieve outstanding cyclic stability(3000 h at 2 mA cm^(-2),2 mA h cm^(-2)and 1300 h at 5 mA cm^(-2),5 mA h cm^(-2)),high average Coulombic efficiency(99.4%over 3200 cycles),and high depth of discharge(80%for 500 h).Besides,the assembled Zn‖NaV_(3)O_(8)·1.5H_(2)O full cells deliver remarkable capacity retention and ultra-long lifetime(61.8%over 6650 cycles at 5 A g^(-1))and enhanced rate capability(169 mA h g^(-1)at 5 A g^(-1)).The work may promote the design and deep understanding of electrolyte additives with high molecular polarity for high-performance AZMBs.展开更多
The formation and evolution process of the solid electrolyte interphase(SEI)is critical for stable cycling of the lithium metal anode(LMA).The concept of regulating SEI components with additives is widely incorporated...The formation and evolution process of the solid electrolyte interphase(SEI)is critical for stable cycling of the lithium metal anode(LMA).The concept of regulating SEI components with additives is widely incorporated into electrolyte design,as these additives can alter the lithium ion(Li^(+))deposition behavior on the surface of LMA.However,conventional additives are limited in their ability to produce only loose and porous SEI.In this study,we propose an organic additive of methyl methacrylate(MMA)that facilitates in-situ polymerization on the surface of LMA by generating anions or free radicals from LiTFSI.The MMA and LiNO_(3) work in tandem to produce a polymer/inorganic SEI(PI-SEI)characterized by an outer layer enriched with PMMA-Li short-chain polymers and an inner layer enriched with Li_(2)O and Li3N inorganics.Unlike the SEI formed by conventional additives,this PI-SEI exhibits higher stability and better Li^(+)transfer properties.The presence of short-chain polymers in PI-SEI alters the transport uniformity of Li^(+),facilitating stable cycling of Li‖Li cell for over 2000 cycles with a capacity of 1 mAh cm^(-2).Furthermore,these PMMA-Li can chemically adsorb lithium poly sulfides(LiPSs),thereby inhibiting Li corrosion by LiPSs,and enabling the capacity of lithium-sulfur batteries to achieve 474.3 mAh g^(-1)after 500 cycles at 0.5C.This study presents a strategy for generating SEI through the in-situ polymerization,which supports the commercial development of LMA in future liquid/solid Li metal batteries.展开更多
Zinc-ion hybrid supercapacitors(ZHSs)are promising energy storage systems integrating high energy density and high-power density,whereas they are plagued by the poor electrochemical stability and inferior kinetics of ...Zinc-ion hybrid supercapacitors(ZHSs)are promising energy storage systems integrating high energy density and high-power density,whereas they are plagued by the poor electrochemical stability and inferior kinetics of zinc anodes.Herein,we report an electrolyte additive-assembled interconnecting molecules-zinc anode interface,realizing highly stable and fast-kinetics zinc anodes for ZHSs.The sulfobutyl groups-graftedβ-cyclodextrin(SC)supramolecules as a trace additive in ZnSO_(4)electrolytes not only adsorb on zinc anodes but also self-assemble into an interconnecting molecule interface benefiting from the mutual attraction between the electron-rich sulfobutyl group and the electron-poor cavity of the adjacent SC supramolecule.The interconnecting molecules-zinc anode interface provides abundant anion-trapping cavities and zincophilic groups to enhance Zn^(2+)transference number and homogenize Zn^(2+)deposition sites,and meanwhile,it accelerates the desolvation of hydrated Zn^(2+)to improve zinc deposition kinetics and inhibit active water molecules from inducing parasitic reactions at the zinc deposition interface,making zinc anodes present superior reversibility with 99.7%Coulombic efficiency,~30 times increase in operation lifetime and an outstanding cumulative capacity at large current densities.ZHSs with 20,000-cycle life and optimized rate capability are thereby achieved.This work provides an inspiring strategy for designing zinc anode interfaces to promote the development of ZHSs.展开更多
Lithium metal has emerged as a highly promising anode material for enhancing the energy density of secondary batteries,attributed to its high theoretical specific capacity and low electrochemical potential.However,saf...Lithium metal has emerged as a highly promising anode material for enhancing the energy density of secondary batteries,attributed to its high theoretical specific capacity and low electrochemical potential.However,safety concerns related to lithium dendrite-induced short circuits and suboptimal electrochemical performance have impeded the commercial viability of lithium metal batteries.Current research efforts primarily focus on altering the solvated structure of Li+by modifying the current collector or introducing electrolyte additives to lower the nucleation barrier,expedite the desolvation process,and suppress the growth of lithium dendrites.Nevertheless,an integrated approach that combines the advantages of these two strategies remains elusive.In this study,we successfully employed metal-organic salt additives with lithophilic properties to accelerate the desolvation process,reduce the nucleation barrier of Li+,and modulate its solvated structure.This approach enhanced the inorganic compound content in the solid electrolyte interphase(SEI)on lithium foil surfaces,leading to stable Li+deposition and stripping.Specifically,Li||Cu cells demonstrated excellent cycle life and Coulombic efficiency(97.28%and 98.59%,respectively)at 0.5 m A/cm^(2)@0.5 m Ah/cm^(2)and 1 m A/cm^(2)@1 m Ah/cm^(2)for 410 and 240 cycles,respectively.Li||Li symmetrical cells showed no short circuit at 1 m A/cm^(2)@1 m Ah/cm^(2)for 1150 h,and Li||LFP full cells retained 68.9%of their capacity(104.6 m Ah/g)after 250 cycles at N/P(1.1:1.0)with a current density of 1C.展开更多
The growth of dendrites and the side reactions occurring at the Zn anode pose significant challenges to the commercialization of aqueous Zn-ion batteries(AZIBs). These challenges arise from the inherent conflict betwe...The growth of dendrites and the side reactions occurring at the Zn anode pose significant challenges to the commercialization of aqueous Zn-ion batteries(AZIBs). These challenges arise from the inherent conflict between mass transfer and electrochemical kinetics. In this study, we propose the use of a multifunctional electrolyte additive based on the xylose(Xylo) molecule to address these issues by modulating the solvation structure and electrode/electrolyte interface, thereby stabilizing the Zn anode. The introduction of the additive alters the solvation structure, creating steric hindrance that impedes charge transfer and then reduces electrochemical kinetics. Furthermore, in-situ analyses demonstrate that the reconstructed electrode/electrolyte interface facilitates stable and rapid Zn^(2+)ion migration and suppresses corrosion and hydrogen evolution reactions. As a result, symmetric cells incorporating the Xylo additive exhibit significantly enhanced reversibility during the Zn plating/stripping process, with an impressively long lifespan of up to 1986 h, compared to cells using pure ZnSO4electrolyte. When combined with a polyaniline cathode, the full cells demonstrate improved capacity and long-term cyclic stability. This work offers an effective direction for improving the stability of Zn anode via electrolyte design, as well as highperformance AZIBs.展开更多
Aqueous zinc-ion batteries(AZIBs)have emerged as a promising next-generation energy storage solution due to their high energy density,abundant resources,low cost,and high safety.However,unstable zinc anode caused by s...Aqueous zinc-ion batteries(AZIBs)have emerged as a promising next-generation energy storage solution due to their high energy density,abundant resources,low cost,and high safety.However,unstable zinc anode caused by side reactions and dendritic growth always severely worsens the long-term operation of AZIBs.Herein,a novel 3-cyclobutene sulfone(CS)additive was employed in the aqueous electrolyte to achieve a highly reversible Zn anode.The CS additive can offer strong electronegativity and high binding energy for the coordination with Zn^(2+),which enables its entry into the solvent sheath structure of Zn^(2+)and eliminates the free H_(2)O molecules from the solvated{Zn^(2+)-SO_(4)^(2-)-(H_(2)O)_(5)}.Thus,the occurrence of side reactions and dendritic growth can be effectively inhibited.Accordingly,the Zn anode achieves long cycle-life(1400 h at 1 m A cm^(-2),1 m Ah cm^(-2),and 400 h at 5 m A cm^(-2),5 m Ah cm^(-2))and high average coulombic efficiency(99.5% over 500 cycles at 10 m A cm^(-2),1 m Ah cm^(-2)).Besides,the assembled Zn||NH_(4)V_(4)O_(10)full cell suggests enhanced cycling reversibility(123.8 m Ah g^(-1)over 500 cycles at 2 A g^(-1),84.9 m Ah g^(-1)over 800 cycles at 5 A g^(-1))and improved rate capability(139.1 m Ah g^(-1)at 5 A g^(-1)).This work may exhibit the creative design and deep understanding of sulfone-based electrolyte additives for the achievement of high-performance AZIBs.展开更多
Aqueous zinc-ion batteries(AZIBs) have garnered significant attention as promising candidates for gridscale energy storage.However,the interfacial instability of zinc anodes caused by the hydrogen evolution reaction(H...Aqueous zinc-ion batteries(AZIBs) have garnered significant attention as promising candidates for gridscale energy storage.However,the interfacial instability of zinc anodes caused by the hydrogen evolution reaction(HER) and aqueous electrolyte corrosion severely restricts their practical implementation.This study introduces 2-mercaptothiazoline(MT) as a dynamic electrolyte additive,leveraging its thiolthione tautomerism for interfacial stabilization.Theoretical calculations and experimental investigations reveal that MT can adsorb onto the zinc surface to form a protective layer to suppress corrosion.Simultaneously,the spatial effect of the thiazoline ring prevents excessive molecular aggregation while enabling homogeneous Zn^(2+) electrodeposition.The electronegativity difference between sulfur and nitrogen atoms induces localized polarization,strengthening electronic interactions with the metal surface to accelerate Zn^(2+) reduction kinetics and inhibit side reactions.Consequently,smooth and low-porosity Zn deposits with enhanced interfacial stability are achieved.The optimized Zn//Zn symmetric cells exhibit extraordinary cycling stability exceeding 1800 h at 0.5 mA cm^(-2),0.5 mAh cm^(-2),while sustaining400 h of operation at 28.5 % depth of discharge(DOD).Zn//MnO_(2) full cells incorporating MT additive maintain 122.6 mAh g^(-1) capacity retention after 500 cycles(1 A g^(-1)).This work provides a facile yet effective strategy for stabilizing Zn metal-based batteries through synergistic interface engineering.展开更多
Aqueous zinc-ion batteries(AZIBs)are promising due to the advantages of metallic zinc,including the high specific capacity(820 mAh g^(-1)),low redox potential(−0.76 V vs.SHE),inherent safety,low cost,and environmental...Aqueous zinc-ion batteries(AZIBs)are promising due to the advantages of metallic zinc,including the high specific capacity(820 mAh g^(-1)),low redox potential(−0.76 V vs.SHE),inherent safety,low cost,and environmental sustainability.Despite these benefits,AZIBs face challenges such as uneven Zn deposition and excessive hydrogen evolution reaction(HER)at the Zn anode,which reduce the battery's coulombic efficiency and cycling life.This study introduces an ammonium formate(AF)additive into a 2.0 M ZnSO_(4) electrolyte to address these issues.The AF additive promotes the three-dimensional rapid diffusion of Zn^(2+)on the anode surface and induces the preferential Zn(002)plane deposition,thus inhibiting dendrite growth and enhancing cycling stability.It also disrupts the hydrogen bond network of electrolyte,reducing the number of active H2O molecules and suppressing H_(2)O-induced side reactions.Consequently,the Zn||Zn symmetric cell with the AF additive shows stable cycling over 2100 h at 5.0 mA cm^(−2) with an areal capacity of 1.0 mAh cm^(−2),and maintains stability over 9700 cycles at 30 mA cm^(−2).When applied in a Zn||VO_(2) full cell,it achieves capacity retention of 68.9%after 2000 cycles,which demonstrates significant performance improvements in AZIBs.展开更多
Effects of film-forming additive on stability of electrode and cycling performance of LiFePO4/graphite cell at elevated temperature were studied. Two 18650 cells with and without VC additive were investigated by galva...Effects of film-forming additive on stability of electrode and cycling performance of LiFePO4/graphite cell at elevated temperature were studied. Two 18650 cells with and without VC additive were investigated by galvanostatic cycling, electrochemical impedance spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis and Raman spectroscopy. The results show that in the presence of VC additive, dissolution of Fe from LiFePO4 material is greatly depressed and stability of graphite structure is improved; the additive can not only reduce reaction of electrolyte on surface of LiFePO4 electrode but also suppress reduction of solvent and thickening of the solid electrolyte interface （SEI） layer on graphite surface. Electrolyte with VC is considered to be a good candidate for improving cycling performance of the LiFePOa/graphite cell at elevated temperature.展开更多
As one of the most important components of the vanadium redox flow battery （VRFB）, the electrolyte can impose a significant impact on cell properties, performance and capital cost. In particular, the electrolyte com...As one of the most important components of the vanadium redox flow battery （VRFB）, the electrolyte can impose a significant impact on cell properties, performance and capital cost. In particular, the electrolyte composition will influence energy density, operating temperature range and the practical applications of the VRFB. Various approaches to increase the energy density and operating temperature range have been proposed. The presence of electrolyte impurities, or the addition of a small amount of other chemical species into the vanadium solution can alter the stability of the electrolyte and influence cell perfor- mance, operating temperature range, energy density, electrochemical kinetics and cost effectiveness. This review provides a detailed overview of research on electrolyte additives including stabilizing agents, im- mobilizing agents, kinetic enhancers, as well as electrolyte impurities and chemical reductants that can be used for different purposes in the VRFBs.展开更多
Zinc metal batteries have been considered as a promising candidate for next-generation batteries due to their high safety and low cost.However,their practical applications are severely hampered by the poor cyclability...Zinc metal batteries have been considered as a promising candidate for next-generation batteries due to their high safety and low cost.However,their practical applications are severely hampered by the poor cyclability that caused by the undesired dendrite growth of metallic Zn.Herein,Ti_(3)C_(2)T_(x) MXene was first used as electrolyte additive to facilitate the uniform Zn deposition by controlling the nucleation and growth process of Zn.Such MXene additives can not only be absorbed on Zn foil to induce uniform initial Zn deposition via providing abundant zincophilic-O groups and subsequently participate in the formation of robust solid-electrolyte interface film,but also accelerate ion transportation by reducing the Zn^(2+) concentration gradient at the electrode/electrolyte interface.Consequently,MXene-containing electrolyte realizes dendrite-free Zn plating/striping with high Coulombic efficiency(99.7%)and superior reversibility(stably up to 1180 cycles).When applied in full cell,the Zn-V_(2)O_(5)cell also delivers significantly improved cycling performances.This work provides a facile yet effective method for developing reversible zinc metal batteries.展开更多
High energy density lithium-ion batteries using Ni-rich cathode(such as LiNi0.6Co0.2Mn0.2O2) suffer from severe capacity decay.P-toluenesulfonyl fluoride(pTSF) has been investigated as a novel film-forming electrolyte...High energy density lithium-ion batteries using Ni-rich cathode(such as LiNi0.6Co0.2Mn0.2O2) suffer from severe capacity decay.P-toluenesulfonyl fluoride(pTSF) has been investigated as a novel film-forming electrolyte additive to enhance the cycling performances of graphite/LiNi0.6Co0.2Mn0.2O2 pouch cell.In comparison with the baseline electrolyte,a small dose of pTSF can significantly improve the cyclic stability of the cell.Theoretical calculations together with experimental results indicate that pTSF would be oxidized and reduced to construct protective interphase film on the surfaces of LiNi0.6Co0.2Mn0.2O2 cathode and graphite anode,respectively.These S-containing surface films derived from pTSF effectively mitigate the decomposition of electrolyte,reduce the interphasial impedance,as well as prevent the dissolution of transition metal ions from Ni-rich cathode upon cycling at high voltage.This finding is beneficial for the practical application of high energy density graphite/LiNi0.6Co0.2Mn0.2O2 cells.展开更多
Lithium metal is one of the most promising anode materials for rechargeable battery with high energy density,but its practical use is still hindered by two main problems,namely,lithium dendrite growth and low Coulombi...Lithium metal is one of the most promising anode materials for rechargeable battery with high energy density,but its practical use is still hindered by two main problems,namely,lithium dendrite growth and low Coulombic efficiency.To address the issues,cesium nitrate(CsNO3)is selected as the additive to modify the electrolyte for lithium secondary battery.Here we report electrochemical performance of lithium secondary battery with different concentration of CsNO3 as electrolyte additive.The study result demonstrates that Coulombic efficiency of Li–Cu cells and the lifetime of symmetric lithium cells contained CsNO3 additive are improved greatly.Li–Cu cell with 0.05 mol/L CsNO3 and 0.15 mol/L LiNO3 as electrolyte additive presents the best electrochemical performance,having the highest Coulombic efficiency of around 97%and the lowest interfacial resistance.With increasing the concentration of CsNO3 as electrolyte additive,the electrochemical performance of cells becomes poor.Meanwhile,the morphology of lithium deposited films with CsNO3-modified electrolyte become smoother and more uniform compared with the basic electrolyte.展开更多
Because of their high capacity and low potential,lithium metal anodes are considered to be promising candidates for next generation electrode materials.However,the safety concerns and limited cycling life associated w...Because of their high capacity and low potential,lithium metal anodes are considered to be promising candidates for next generation electrode materials.However,the safety concerns and limited cycling life associated with uncontrollable dendrite growth hamper practical applications.In this work,the acidified cellulose ester,which is a mixed fiber microporous membrane film,was used as a novel electrolyte additive that effectively improves the cycle stability of the lithium metal anode and inhibits dendrite growth.The focus of this paper is on inhibiting the formation and growth of lithium dendrites.The coulombic efficiency of a Li|Cu battery with this acidified cellulose ester additive remains stable at 99%after 500 cycles under a current density of 1 mA/cm^2.Symmetric batteries also remain stable after 500 cycles(1000 h)under a current density of 1 mA/cm^2.These superior properties can be ascribed to the induced nucleation and the uniform distribution of lithium ion flux.This study uncovers an approach for effectively enabling stable cycling of dendrite-free lithium metal anodes.展开更多
Rechargeable lithium-sulfur(Li-S)batteries are considered one of the most promising energy storage techniques owing to the high theoretical energy density.However,challenges still remain such as the shuttle effect of ...Rechargeable lithium-sulfur(Li-S)batteries are considered one of the most promising energy storage techniques owing to the high theoretical energy density.However,challenges still remain such as the shuttle effect of lithium polysulfides(LPSs)and the instability of lithium metal anode.Herein,we propose to use nitrogen-rich azoles,i.e.,triazole(Ta)and tetrazole(Tta),as trifunctional electrolyte additives for Li-S batteries.The azoles afford strong lithiophilicity for the chemisorption of LPSs.The density functional theory and experimental analysis verify the presence of Li bonds between the azoles and LPSs.The azoles can also interact with lithium salt in the electrolyte,leading to increase ionic conductivity and lithiumion transference number.Moreover,the azoles render particle-like lithium deposition on the lithium metal anode,leading to superlong cycling of a Li symmetric cell.The Li-S batteries with Ta and Tta exhibit the initial discharge capacity of 1425.5 and 1322.2 m Ah g^(-1),respectively,at 0.2 C rate,and promising cycling stability.They also enable enhanced cycling performance of a Li-organosulfide battery.展开更多
High voltage is necessary for high energy lithium-ion batteries but difficult to achieve because of the highly deteriorated cyclability of the batteries.A novel strategy is developed to extend cyclability of a high vo...High voltage is necessary for high energy lithium-ion batteries but difficult to achieve because of the highly deteriorated cyclability of the batteries.A novel strategy is developed to extend cyclability of a high voltage lithium-ion battery,LiNi_(0.5)Mn_(1.5)O_(4)/Graphite(LNMO/Graphite)cell,which emphasizes a rational design of an electrolyte additive that can effectively construct protective interphases on anode and cathode and highly eliminate the effect of hydrogen fluoride(HF).5-Trifluoromethylpyridine-trime thyl lithium borate(LTFMP-TMB),is synthesized,featuring with multi-functionalities.Its anion TFMPTMB-tends to be enriched on cathode and can be preferentially oxidized yielding TMB and radical TFMP-.Both TMB and radical TFMP can combine HF and thus eliminate the detrimental effect of HF on cathode,while the TMB dragged on cathode thus takes a preferential oxidation and constructs a protective cathode interphase.On the other hand,LTFMP-TMB is preferentially reduced on anode and constructs a protective anode interphase.Consequently,a small amount of LTFMP-TMB(0.2%)in 1.0 M LiPF6in EC/DEC/EMC(3/2/5,wt%)results in a highly improved cyclability of LNMO/Graphite cell,with the capacity retention enhanced from 52%to 80%after 150 cycles at 0.5 C between 3.5 and 4.8 V.The as-developed strategy provides a model of designing electrolyte additives for improving cyclability of high voltage batteries.展开更多
The development of high voltage electrolytes plays a critical role to achieve advanced lithium ion batteries with high energy density.Application of suitable electrolyte additives is a facile and effective way to achi...The development of high voltage electrolytes plays a critical role to achieve advanced lithium ion batteries with high energy density.Application of suitable electrolyte additives is a facile and effective way to achieve enhanced electrochemical perfo rmance at high voltage operation.In this work,2-(tri fluoroacetyl)thiophene(TFPN) was investigated as a functional electrolyte additive for high performance lithium ion batteries using high-voltage LiCoO2 cathode.When cycled between 3.0 V and 4.4 V at 0.5 C,the capacity retention of the LiCoO2 cathode significantly increases from 33.2 %-90.6 % by the addition of 0.5 wt%TFPN into the baseline electrolyte.Based on the measurements on impedance spectra and X-ray photoelectron spectra,the improved cycling performance is attributed to the preferential oxidation of TFPN on the cathode surface and thus form a protective layer to suppress the decomposition of both electrolyte solvent and lithium salt.This work presents that TFPN has great potential as functional additive for the development of high-voltage and high-energy-density lithium ion batteries.展开更多
The effects of methylene methanedisulfonate（MMDS） on the high-temperature（0℃） cycle performance of LiMnO/graphite cells are investigated.By addition of 2 wt%MMDS into a routine electrolyte,the high-temperature cy...The effects of methylene methanedisulfonate（MMDS） on the high-temperature（0℃） cycle performance of LiMnO/graphite cells are investigated.By addition of 2 wt%MMDS into a routine electrolyte,the high-temperature cycling performance of LiMn204/graphite cells can be significantly improved.The analysis of differential capacity curves and energy-dispersive X-ray spectrometry（EDX） indicates that MMDS decomposed on both cathode and anode.The three-electrode system of pouch cell is used to reveal the capacity loss mechanism in the cells.It is shown that the capacity fading of cells without MMDS in the electrolytes is due to irreversible lithium consumption during cycling and irreversible damage of LiMnOmaterial,while the capacity fading of cell with 2 wt%MMDS in electrolytes mainly originated from irreversible lithium consumption during cycling.展开更多
基金supported by a Discovery Early Career Researcher Award (DECRA,No.DE180101478) of the Australian Research CouncilNational Natural Science Foundation of China (Youth Program,No.52204378).
文摘Aqueous-electrolyte-based zinc-ion batteries(ZIBs),which have significant advantages over other batteries,including low cost,high safety,high ionic conductivity,and a natural abundance of zinc,have been regarded as a potential alternative to lithium-ion batteries(LIBs).ZIBs still face some critical challenges,however,especially for building a reversible zinc anode.To address the reversibility of zinc anode,great efforts have been made on intrinsic anode engineering and anode interface modification.Less attention has been devoted to the electrolyte additives,however,which could not only significantly improve the reversibility of zinc anode,but also determine the viability and overall performance of ZIBs.This review aims to provide an overview of the two main functions of electrolyte additives,followed by details on six reasons why additives might improve the performance of ZIBs from the perspectives of creating new layers and regulating current plating/stripping processes.Furthermore,the remaining difficulties and potential directions for additives in aqueous ZIBs are also highlighted.
基金supported by the National Natural Science Foundation of China(No.52001015)the Urban Carbon Neutral Science Innovation Foundation of Beijing University of Technology,China(No.053000514124601)the Science and Technology Program of Beijing Municipal Education Commission,China(No.KM201810005007).
文摘The addition of complexing agents to the electrolyte has been shown to be an effective method to enhance the discharge performance of magnesium-air batteries.In this work,four complexing agents:citric acid(CIT),salicylic acid(SAL),2,6-dihydroxybenzoic acid(2,6-DHB),and 5-sulfoisophthalic acid(5-sulfoSAL)were selected as potential candidates.Through electrochemical tests,full-cell discharge experiments,and physicochemical characterization,the impact of these complexing agents on the discharge performance of magnesium-air batteries using AZ31 alloy as the anode material was investigated.The results demonstrated that the four complexing agents increased the discharge voltage of the batteries.Notably,SAL could significantly improve the anodic efficiency and the discharge specific capacity,achieving an anodic efficiency of 60.3%and a specific capacity of 1358.3 mA·h/g at a discharge current density of 10 mA/cm^(2).
基金the financial support from the Foshan Talents Special Foundation(BKBS202003).
文摘Unstable Zn interface caused by rampant dendrite growth and parasitic side reactions always hinders the practical application of aqueous zinc metal batteries(AZMBs),Herein,tyrosine(Tyr)with high molecular polarity was introduced into aqueous electrolyte to modulate the interfacial electrochemistry of Zn anode.In AZMBs,the positively charged side of Tyr can be well adsorbed on the surface of Zn anode to form a water-poor layer,and the exposed carboxylate side can be easily coordinated with Zn^(2+),favoring inducing uniform plating of Zn^(2+)and inhibiting the occurrence of water-induced side reactions.These in turn enable the achievement of highly stable Zn anode.Accordingly,the Zn anodes achieve outstanding cyclic stability(3000 h at 2 mA cm^(-2),2 mA h cm^(-2)and 1300 h at 5 mA cm^(-2),5 mA h cm^(-2)),high average Coulombic efficiency(99.4%over 3200 cycles),and high depth of discharge(80%for 500 h).Besides,the assembled Zn‖NaV_(3)O_(8)·1.5H_(2)O full cells deliver remarkable capacity retention and ultra-long lifetime(61.8%over 6650 cycles at 5 A g^(-1))and enhanced rate capability(169 mA h g^(-1)at 5 A g^(-1)).The work may promote the design and deep understanding of electrolyte additives with high molecular polarity for high-performance AZMBs.
基金financially supported by Jilin Province Science and Technology Department Program(Nos.YDZJ202201ZYTS304,20220201130GX and 20240101004JJ)the National Natural Science Foundation of China(Nos.52171210 and 52471229)the Science and Technology Project of Jilin Provincial Education Department(No.JJKH20220428KJ)
文摘The formation and evolution process of the solid electrolyte interphase(SEI)is critical for stable cycling of the lithium metal anode(LMA).The concept of regulating SEI components with additives is widely incorporated into electrolyte design,as these additives can alter the lithium ion(Li^(+))deposition behavior on the surface of LMA.However,conventional additives are limited in their ability to produce only loose and porous SEI.In this study,we propose an organic additive of methyl methacrylate(MMA)that facilitates in-situ polymerization on the surface of LMA by generating anions or free radicals from LiTFSI.The MMA and LiNO_(3) work in tandem to produce a polymer/inorganic SEI(PI-SEI)characterized by an outer layer enriched with PMMA-Li short-chain polymers and an inner layer enriched with Li_(2)O and Li3N inorganics.Unlike the SEI formed by conventional additives,this PI-SEI exhibits higher stability and better Li^(+)transfer properties.The presence of short-chain polymers in PI-SEI alters the transport uniformity of Li^(+),facilitating stable cycling of Li‖Li cell for over 2000 cycles with a capacity of 1 mAh cm^(-2).Furthermore,these PMMA-Li can chemically adsorb lithium poly sulfides(LiPSs),thereby inhibiting Li corrosion by LiPSs,and enabling the capacity of lithium-sulfur batteries to achieve 474.3 mAh g^(-1)after 500 cycles at 0.5C.This study presents a strategy for generating SEI through the in-situ polymerization,which supports the commercial development of LMA in future liquid/solid Li metal batteries.
基金the National Key R&D Program of China(2022YFB2404500)Guangdong Basic and Applied Basic Research Foundation(2023A1515110347+2 种基金2023A1515012087)Funding by Science and Technology Projects in Guangzhou(2024A04J3267)the Fundamental Research Funds for the Central Universities(21624411).
文摘Zinc-ion hybrid supercapacitors(ZHSs)are promising energy storage systems integrating high energy density and high-power density,whereas they are plagued by the poor electrochemical stability and inferior kinetics of zinc anodes.Herein,we report an electrolyte additive-assembled interconnecting molecules-zinc anode interface,realizing highly stable and fast-kinetics zinc anodes for ZHSs.The sulfobutyl groups-graftedβ-cyclodextrin(SC)supramolecules as a trace additive in ZnSO_(4)electrolytes not only adsorb on zinc anodes but also self-assemble into an interconnecting molecule interface benefiting from the mutual attraction between the electron-rich sulfobutyl group and the electron-poor cavity of the adjacent SC supramolecule.The interconnecting molecules-zinc anode interface provides abundant anion-trapping cavities and zincophilic groups to enhance Zn^(2+)transference number and homogenize Zn^(2+)deposition sites,and meanwhile,it accelerates the desolvation of hydrated Zn^(2+)to improve zinc deposition kinetics and inhibit active water molecules from inducing parasitic reactions at the zinc deposition interface,making zinc anodes present superior reversibility with 99.7%Coulombic efficiency,~30 times increase in operation lifetime and an outstanding cumulative capacity at large current densities.ZHSs with 20,000-cycle life and optimized rate capability are thereby achieved.This work provides an inspiring strategy for designing zinc anode interfaces to promote the development of ZHSs.
基金supported by Yunnan Natural Science Foundation Project(No.202202AG050003)Yunnan Fundamental Research Projects(Nos.202101BE070001-018 and 202201AT070070)+1 种基金the National Youth Talent Support Program of Yunnan Province China(No.YNQR-QNRC-2020-011)Yunnan Engineering Research Center Innovation Ability Construction and Enhancement Projects(No.2023-XMDJ-00617107)。
文摘Lithium metal has emerged as a highly promising anode material for enhancing the energy density of secondary batteries,attributed to its high theoretical specific capacity and low electrochemical potential.However,safety concerns related to lithium dendrite-induced short circuits and suboptimal electrochemical performance have impeded the commercial viability of lithium metal batteries.Current research efforts primarily focus on altering the solvated structure of Li+by modifying the current collector or introducing electrolyte additives to lower the nucleation barrier,expedite the desolvation process,and suppress the growth of lithium dendrites.Nevertheless,an integrated approach that combines the advantages of these two strategies remains elusive.In this study,we successfully employed metal-organic salt additives with lithophilic properties to accelerate the desolvation process,reduce the nucleation barrier of Li+,and modulate its solvated structure.This approach enhanced the inorganic compound content in the solid electrolyte interphase(SEI)on lithium foil surfaces,leading to stable Li+deposition and stripping.Specifically,Li||Cu cells demonstrated excellent cycle life and Coulombic efficiency(97.28%and 98.59%,respectively)at 0.5 m A/cm^(2)@0.5 m Ah/cm^(2)and 1 m A/cm^(2)@1 m Ah/cm^(2)for 410 and 240 cycles,respectively.Li||Li symmetrical cells showed no short circuit at 1 m A/cm^(2)@1 m Ah/cm^(2)for 1150 h,and Li||LFP full cells retained 68.9%of their capacity(104.6 m Ah/g)after 250 cycles at N/P(1.1:1.0)with a current density of 1C.
文摘The growth of dendrites and the side reactions occurring at the Zn anode pose significant challenges to the commercialization of aqueous Zn-ion batteries(AZIBs). These challenges arise from the inherent conflict between mass transfer and electrochemical kinetics. In this study, we propose the use of a multifunctional electrolyte additive based on the xylose(Xylo) molecule to address these issues by modulating the solvation structure and electrode/electrolyte interface, thereby stabilizing the Zn anode. The introduction of the additive alters the solvation structure, creating steric hindrance that impedes charge transfer and then reduces electrochemical kinetics. Furthermore, in-situ analyses demonstrate that the reconstructed electrode/electrolyte interface facilitates stable and rapid Zn^(2+)ion migration and suppresses corrosion and hydrogen evolution reactions. As a result, symmetric cells incorporating the Xylo additive exhibit significantly enhanced reversibility during the Zn plating/stripping process, with an impressively long lifespan of up to 1986 h, compared to cells using pure ZnSO4electrolyte. When combined with a polyaniline cathode, the full cells demonstrate improved capacity and long-term cyclic stability. This work offers an effective direction for improving the stability of Zn anode via electrolyte design, as well as highperformance AZIBs.
基金the financial support from the Foshan Talents Special Foundation(BKBS202003)。
文摘Aqueous zinc-ion batteries(AZIBs)have emerged as a promising next-generation energy storage solution due to their high energy density,abundant resources,low cost,and high safety.However,unstable zinc anode caused by side reactions and dendritic growth always severely worsens the long-term operation of AZIBs.Herein,a novel 3-cyclobutene sulfone(CS)additive was employed in the aqueous electrolyte to achieve a highly reversible Zn anode.The CS additive can offer strong electronegativity and high binding energy for the coordination with Zn^(2+),which enables its entry into the solvent sheath structure of Zn^(2+)and eliminates the free H_(2)O molecules from the solvated{Zn^(2+)-SO_(4)^(2-)-(H_(2)O)_(5)}.Thus,the occurrence of side reactions and dendritic growth can be effectively inhibited.Accordingly,the Zn anode achieves long cycle-life(1400 h at 1 m A cm^(-2),1 m Ah cm^(-2),and 400 h at 5 m A cm^(-2),5 m Ah cm^(-2))and high average coulombic efficiency(99.5% over 500 cycles at 10 m A cm^(-2),1 m Ah cm^(-2)).Besides,the assembled Zn||NH_(4)V_(4)O_(10)full cell suggests enhanced cycling reversibility(123.8 m Ah g^(-1)over 500 cycles at 2 A g^(-1),84.9 m Ah g^(-1)over 800 cycles at 5 A g^(-1))and improved rate capability(139.1 m Ah g^(-1)at 5 A g^(-1)).This work may exhibit the creative design and deep understanding of sulfone-based electrolyte additives for the achievement of high-performance AZIBs.
基金supported by the Natural Science Foundation of Hunan Province (No.2020JJ4734)supported in part by the High Performance Computing Center of Central South University。
文摘Aqueous zinc-ion batteries(AZIBs) have garnered significant attention as promising candidates for gridscale energy storage.However,the interfacial instability of zinc anodes caused by the hydrogen evolution reaction(HER) and aqueous electrolyte corrosion severely restricts their practical implementation.This study introduces 2-mercaptothiazoline(MT) as a dynamic electrolyte additive,leveraging its thiolthione tautomerism for interfacial stabilization.Theoretical calculations and experimental investigations reveal that MT can adsorb onto the zinc surface to form a protective layer to suppress corrosion.Simultaneously,the spatial effect of the thiazoline ring prevents excessive molecular aggregation while enabling homogeneous Zn^(2+) electrodeposition.The electronegativity difference between sulfur and nitrogen atoms induces localized polarization,strengthening electronic interactions with the metal surface to accelerate Zn^(2+) reduction kinetics and inhibit side reactions.Consequently,smooth and low-porosity Zn deposits with enhanced interfacial stability are achieved.The optimized Zn//Zn symmetric cells exhibit extraordinary cycling stability exceeding 1800 h at 0.5 mA cm^(-2),0.5 mAh cm^(-2),while sustaining400 h of operation at 28.5 % depth of discharge(DOD).Zn//MnO_(2) full cells incorporating MT additive maintain 122.6 mAh g^(-1) capacity retention after 500 cycles(1 A g^(-1)).This work provides a facile yet effective strategy for stabilizing Zn metal-based batteries through synergistic interface engineering.
基金supported by the Natural Science Foundation of Guangxi(2022JJD120011)the National Natural Science Foundation of China(22479031,22162004).
文摘Aqueous zinc-ion batteries(AZIBs)are promising due to the advantages of metallic zinc,including the high specific capacity(820 mAh g^(-1)),low redox potential(−0.76 V vs.SHE),inherent safety,low cost,and environmental sustainability.Despite these benefits,AZIBs face challenges such as uneven Zn deposition and excessive hydrogen evolution reaction(HER)at the Zn anode,which reduce the battery's coulombic efficiency and cycling life.This study introduces an ammonium formate(AF)additive into a 2.0 M ZnSO_(4) electrolyte to address these issues.The AF additive promotes the three-dimensional rapid diffusion of Zn^(2+)on the anode surface and induces the preferential Zn(002)plane deposition,thus inhibiting dendrite growth and enhancing cycling stability.It also disrupts the hydrogen bond network of electrolyte,reducing the number of active H2O molecules and suppressing H_(2)O-induced side reactions.Consequently,the Zn||Zn symmetric cell with the AF additive shows stable cycling over 2100 h at 5.0 mA cm^(−2) with an areal capacity of 1.0 mAh cm^(−2),and maintains stability over 9700 cycles at 30 mA cm^(−2).When applied in a Zn||VO_(2) full cell,it achieves capacity retention of 68.9%after 2000 cycles,which demonstrates significant performance improvements in AZIBs.
基金Project(2007BAE12B01)supported by the National Key Technology Research and Development Program of ChinaProject(20803095)supported by the National Natural Science Foundation of China
文摘Effects of film-forming additive on stability of electrode and cycling performance of LiFePO4/graphite cell at elevated temperature were studied. Two 18650 cells with and without VC additive were investigated by galvanostatic cycling, electrochemical impedance spectroscopy, scanning electron microscopy, energy-dispersive X-ray analysis and Raman spectroscopy. The results show that in the presence of VC additive, dissolution of Fe from LiFePO4 material is greatly depressed and stability of graphite structure is improved; the additive can not only reduce reaction of electrolyte on surface of LiFePO4 electrode but also suppress reduction of solvent and thickening of the solid electrolyte interface （SEI） layer on graphite surface. Electrolyte with VC is considered to be a good candidate for improving cycling performance of the LiFePOa/graphite cell at elevated temperature.
文摘As one of the most important components of the vanadium redox flow battery （VRFB）, the electrolyte can impose a significant impact on cell properties, performance and capital cost. In particular, the electrolyte composition will influence energy density, operating temperature range and the practical applications of the VRFB. Various approaches to increase the energy density and operating temperature range have been proposed. The presence of electrolyte impurities, or the addition of a small amount of other chemical species into the vanadium solution can alter the stability of the electrolyte and influence cell perfor- mance, operating temperature range, energy density, electrochemical kinetics and cost effectiveness. This review provides a detailed overview of research on electrolyte additives including stabilizing agents, im- mobilizing agents, kinetic enhancers, as well as electrolyte impurities and chemical reductants that can be used for different purposes in the VRFBs.
基金the National Natural Science Foundation of China(No.51902036,51702138,22075115)Natural Science Foundation of Chongqing Science&Technology Commission(No.cstc2019jcyj-msxm1407)+4 种基金Natural Science Foundation of Chongqing Technology and Business University(No.1952009)the Venture&Innovation Support Program for Chongqing Overseas Returnees(Grant No.CX2018129)the Science and Technology Research Program of Chongqing Municipal Education Commission(Grant No.KJQN201900826 and KJQN201800808)the Innovation Group of New Technologies for Industrial Pollution Control of Chongqing Education Commission(Grant No.CXQT19023)Key Disciplines of Chemical Engineering and Technology in Chongqing Colleges and Universities during the 13th Five Year Plan provided the financial support.
文摘Zinc metal batteries have been considered as a promising candidate for next-generation batteries due to their high safety and low cost.However,their practical applications are severely hampered by the poor cyclability that caused by the undesired dendrite growth of metallic Zn.Herein,Ti_(3)C_(2)T_(x) MXene was first used as electrolyte additive to facilitate the uniform Zn deposition by controlling the nucleation and growth process of Zn.Such MXene additives can not only be absorbed on Zn foil to induce uniform initial Zn deposition via providing abundant zincophilic-O groups and subsequently participate in the formation of robust solid-electrolyte interface film,but also accelerate ion transportation by reducing the Zn^(2+) concentration gradient at the electrode/electrolyte interface.Consequently,MXene-containing electrolyte realizes dendrite-free Zn plating/striping with high Coulombic efficiency(99.7%)and superior reversibility(stably up to 1180 cycles).When applied in full cell,the Zn-V_(2)O_(5)cell also delivers significantly improved cycling performances.This work provides a facile yet effective method for developing reversible zinc metal batteries.
基金supported by the National Natural Science Foundation of China (21573080)the Guangdong Program for Support of Distinguished Young Scholar (2017B030306013)the Science and Technology Planning Project of Guangdong Province (2017B090901020)。
文摘High energy density lithium-ion batteries using Ni-rich cathode(such as LiNi0.6Co0.2Mn0.2O2) suffer from severe capacity decay.P-toluenesulfonyl fluoride(pTSF) has been investigated as a novel film-forming electrolyte additive to enhance the cycling performances of graphite/LiNi0.6Co0.2Mn0.2O2 pouch cell.In comparison with the baseline electrolyte,a small dose of pTSF can significantly improve the cyclic stability of the cell.Theoretical calculations together with experimental results indicate that pTSF would be oxidized and reduced to construct protective interphase film on the surfaces of LiNi0.6Co0.2Mn0.2O2 cathode and graphite anode,respectively.These S-containing surface films derived from pTSF effectively mitigate the decomposition of electrolyte,reduce the interphasial impedance,as well as prevent the dissolution of transition metal ions from Ni-rich cathode upon cycling at high voltage.This finding is beneficial for the practical application of high energy density graphite/LiNi0.6Co0.2Mn0.2O2 cells.
基金Project(2016YFB0300801)supported by the National Key Research and Development Program of ChinaProject(2012CB619502)supported by the National Basic Research Program of China
文摘Lithium metal is one of the most promising anode materials for rechargeable battery with high energy density,but its practical use is still hindered by two main problems,namely,lithium dendrite growth and low Coulombic efficiency.To address the issues,cesium nitrate(CsNO3)is selected as the additive to modify the electrolyte for lithium secondary battery.Here we report electrochemical performance of lithium secondary battery with different concentration of CsNO3 as electrolyte additive.The study result demonstrates that Coulombic efficiency of Li–Cu cells and the lifetime of symmetric lithium cells contained CsNO3 additive are improved greatly.Li–Cu cell with 0.05 mol/L CsNO3 and 0.15 mol/L LiNO3 as electrolyte additive presents the best electrochemical performance,having the highest Coulombic efficiency of around 97%and the lowest interfacial resistance.With increasing the concentration of CsNO3 as electrolyte additive,the electrochemical performance of cells becomes poor.Meanwhile,the morphology of lithium deposited films with CsNO3-modified electrolyte become smoother and more uniform compared with the basic electrolyte.
基金supported by“the Fundamental Research Funds for the Central Universities”(No.51772278)。
文摘Because of their high capacity and low potential,lithium metal anodes are considered to be promising candidates for next generation electrode materials.However,the safety concerns and limited cycling life associated with uncontrollable dendrite growth hamper practical applications.In this work,the acidified cellulose ester,which is a mixed fiber microporous membrane film,was used as a novel electrolyte additive that effectively improves the cycle stability of the lithium metal anode and inhibits dendrite growth.The focus of this paper is on inhibiting the formation and growth of lithium dendrites.The coulombic efficiency of a Li|Cu battery with this acidified cellulose ester additive remains stable at 99%after 500 cycles under a current density of 1 mA/cm^2.Symmetric batteries also remain stable after 500 cycles(1000 h)under a current density of 1 mA/cm^2.These superior properties can be ascribed to the induced nucleation and the uniform distribution of lithium ion flux.This study uncovers an approach for effectively enabling stable cycling of dendrite-free lithium metal anodes.
基金supported by the National Natural Science Foundation of China(Grant Nos.U2004214,21975225,and 51902293)。
文摘Rechargeable lithium-sulfur(Li-S)batteries are considered one of the most promising energy storage techniques owing to the high theoretical energy density.However,challenges still remain such as the shuttle effect of lithium polysulfides(LPSs)and the instability of lithium metal anode.Herein,we propose to use nitrogen-rich azoles,i.e.,triazole(Ta)and tetrazole(Tta),as trifunctional electrolyte additives for Li-S batteries.The azoles afford strong lithiophilicity for the chemisorption of LPSs.The density functional theory and experimental analysis verify the presence of Li bonds between the azoles and LPSs.The azoles can also interact with lithium salt in the electrolyte,leading to increase ionic conductivity and lithiumion transference number.Moreover,the azoles render particle-like lithium deposition on the lithium metal anode,leading to superlong cycling of a Li symmetric cell.The Li-S batteries with Ta and Tta exhibit the initial discharge capacity of 1425.5 and 1322.2 m Ah g^(-1),respectively,at 0.2 C rate,and promising cycling stability.They also enable enhanced cycling performance of a Li-organosulfide battery.
基金supported by the National Natural Science Foundation of China(22179041)。
文摘High voltage is necessary for high energy lithium-ion batteries but difficult to achieve because of the highly deteriorated cyclability of the batteries.A novel strategy is developed to extend cyclability of a high voltage lithium-ion battery,LiNi_(0.5)Mn_(1.5)O_(4)/Graphite(LNMO/Graphite)cell,which emphasizes a rational design of an electrolyte additive that can effectively construct protective interphases on anode and cathode and highly eliminate the effect of hydrogen fluoride(HF).5-Trifluoromethylpyridine-trime thyl lithium borate(LTFMP-TMB),is synthesized,featuring with multi-functionalities.Its anion TFMPTMB-tends to be enriched on cathode and can be preferentially oxidized yielding TMB and radical TFMP-.Both TMB and radical TFMP can combine HF and thus eliminate the detrimental effect of HF on cathode,while the TMB dragged on cathode thus takes a preferential oxidation and constructs a protective cathode interphase.On the other hand,LTFMP-TMB is preferentially reduced on anode and constructs a protective anode interphase.Consequently,a small amount of LTFMP-TMB(0.2%)in 1.0 M LiPF6in EC/DEC/EMC(3/2/5,wt%)results in a highly improved cyclability of LNMO/Graphite cell,with the capacity retention enhanced from 52%to 80%after 150 cycles at 0.5 C between 3.5 and 4.8 V.The as-developed strategy provides a model of designing electrolyte additives for improving cyclability of high voltage batteries.
基金This research was financially supported by the National Natural Science Foundation of China(Nos.21676067,51372060and 21606065)the Fundamental Research Funds for the Central Universities(Nos.JZ2017YYPY0253,JZ2018HGBZ0138 and JZ2017HGTB0198)+1 种基金the Anhui Provincial Natural Science Foundation(No.1908085QE178)the Opening Project of CAS Key Laboratory of Materials for Energy Conversion(No.KF2018003)。
文摘The development of high voltage electrolytes plays a critical role to achieve advanced lithium ion batteries with high energy density.Application of suitable electrolyte additives is a facile and effective way to achieve enhanced electrochemical perfo rmance at high voltage operation.In this work,2-(tri fluoroacetyl)thiophene(TFPN) was investigated as a functional electrolyte additive for high performance lithium ion batteries using high-voltage LiCoO2 cathode.When cycled between 3.0 V and 4.4 V at 0.5 C,the capacity retention of the LiCoO2 cathode significantly increases from 33.2 %-90.6 % by the addition of 0.5 wt%TFPN into the baseline electrolyte.Based on the measurements on impedance spectra and X-ray photoelectron spectra,the improved cycling performance is attributed to the preferential oxidation of TFPN on the cathode surface and thus form a protective layer to suppress the decomposition of both electrolyte solvent and lithium salt.This work presents that TFPN has great potential as functional additive for the development of high-voltage and high-energy-density lithium ion batteries.
基金supported by the Key Project of the National Natural Science Foundation of China(Grant No.21233004)
文摘The effects of methylene methanedisulfonate（MMDS） on the high-temperature（0℃） cycle performance of LiMnO/graphite cells are investigated.By addition of 2 wt%MMDS into a routine electrolyte,the high-temperature cycling performance of LiMn204/graphite cells can be significantly improved.The analysis of differential capacity curves and energy-dispersive X-ray spectrometry（EDX） indicates that MMDS decomposed on both cathode and anode.The three-electrode system of pouch cell is used to reveal the capacity loss mechanism in the cells.It is shown that the capacity fading of cells without MMDS in the electrolytes is due to irreversible lithium consumption during cycling and irreversible damage of LiMnOmaterial,while the capacity fading of cell with 2 wt%MMDS in electrolytes mainly originated from irreversible lithium consumption during cycling.
