Solid polymer electrolytes are light-weight, flexible, and non-flammable and provide a feasible solution to the safety issues facing lithium-ion batteries through the replacement of organic liquid electrolytes. Substa...Solid polymer electrolytes are light-weight, flexible, and non-flammable and provide a feasible solution to the safety issues facing lithium-ion batteries through the replacement of organic liquid electrolytes. Substantial research efforts have been devoted to achieving the next generation of solid-state polymer lithium batteries. Herein, we provide a review of the development of solid polymer electrolytes and provide comprehensive insights into emerging developments. In particular, we discuss the different molecular structures of the solid polymer matrices, including polyether, polyester, polyacrylonitrile, and polysiloxane, and their interfacial compatibility with lithium, as well as the factors that govern the properties of the polymer electrolytes. The discussion aims to give perspective to allow the strategic design of state-of-the-art solid polymer electrolytes, and we hope it will provide clear guidance for the exploration of high-performance lithium batteries.展开更多
Conventional lithium-ion batteries(LIBs)with graphite anodes are approaching their theoretical limitations in energy density.Replacing the conventional graphite anodes with high-capacity Si-based anodes represents one...Conventional lithium-ion batteries(LIBs)with graphite anodes are approaching their theoretical limitations in energy density.Replacing the conventional graphite anodes with high-capacity Si-based anodes represents one of the most promising strategies to greatly boost the energy density of LIBs.However,the inherent huge volume expansion of Si-based materials after lithiation and the resulting series of intractable problems,such as unstable solid electrolyte interphase layer,cracking of electrode,and especially the rapid capacity degradation of cells,severely restrict the practical application of Sibased anodes.Over the past decade,numerous reports have demonstrated that polymer binders play a critical role in alleviating the volume expansion and maintaining the integrity and stable cycling of Si-based anodes.In this review,the state-of-the-art designing of polymer binders for Si-based anodes have been systematically summarized based on their structures,including the linear,branched,crosslinked,and conjugated conductive polymer binders.Especially,the comprehensive designing of multifunctional polymer binders,by a combination of multiple structures,interactions,crosslinking chemistries,ionic or electronic conductivities,soft and hard segments,and so forth,would be promising to promote the practical application of Si-based anodes.Finally,a perspective on the rational design of practical polymer binders for the large-scale application of Si-based anodes is presented.展开更多
The interest for solid-state lithium metal(Li◦)batteries(SSLMBs)has been growing exponentially in recent years in view of their higher energy density and eliminated safety concerns.Solid polymer electrolytes(SPEs)are ...The interest for solid-state lithium metal(Li◦)batteries(SSLMBs)has been growing exponentially in recent years in view of their higher energy density and eliminated safety concerns.Solid polymer electrolytes(SPEs)are soft ionic conductors which can be easily processed into thin films at industrial level;these unique features confer solid-state Li◦polymer batteries(SSLMPBs,i.e.,SSLMBs utilizing SPEs as electrolytes)distinct advantages compared to SSLMBs containing other electrolytes.In this article,we briefly review recent progresses and achievements in SSLMPBs including the improvement of ionic conductivity of SPEs and their interfacial stability with Li◦anode.Moreover,we outline several advanced in-situ and ex-situ characterizing techniques which could assist in-depth understanding of the anode-electrolyte interphases in SSLMPBs.This article is hoped not only to update the state-of-the-art in the research on SSLMPBs but also to bring intriguing insights that could improve the fundamental properties(e.g.,transport,dendrite formation,and growth,etc.)and electrochemical performance of SSLMPBs.展开更多
Lithium/polypyrrole （Li/PPy） batteries were fabricated using lithium sheet as cathode, PPy as anode, microporous membrane polypropylene/polyethylene/polypropylene （PP/PE/PP） composite as separator and LiPF6/ethyle...Lithium/polypyrrole （Li/PPy） batteries were fabricated using lithium sheet as cathode, PPy as anode, microporous membrane polypropylene/polyethylene/polypropylene （PP/PE/PP） composite as separator and LiPF6/ethylene carbonate-dimethyl carbonate-methyl ethyl carbonate （EC-DMC-EMC） as electrolyte. Polypyrrole was prepared by chemical polymerization. Certain fundamental electrochemical performances were investigated. Properties of the batteries were characterized and tested by SEM, galvanostatic charge/discharge tests, cyclic voltammetry （CV）, and a.c. impedance spectroscopy. The influences of separator, morphology, and conductivity of PPy anode, cold-molded pressure, and electric current on the performances of the batteries were studied. Using PP/PE/PP membranes as separator, the battery showed good storage stability and cycling property. The conductivity of materials rather than morphology affected the behavior of the battery. The higher the conductivity, the better performances the cells had. Proper cold-molded pressure 20 MPa of the anode pellet would make the properties of the cells good and the fitted charge/discharge current was 0.1 mA. The cells showed excellent performance with 97%-100% coulombic efficiency. The highest discharge capacity of 95.2 mAh/g was obtained.展开更多
Solid polymer electrolytes(SPEs)possess several merits including no leakage,ease in process,and suppressing lithium dendrites growth.These features are beneficial for improving the cycle life and safety performance of...Solid polymer electrolytes(SPEs)possess several merits including no leakage,ease in process,and suppressing lithium dendrites growth.These features are beneficial for improving the cycle life and safety performance of rechargeable lithium metal batteries(LMBs),as compared to conventional non-aqueous liquid electrolytes.Particularly,the superior elasticity of polymeric material enables the employment of SPEs in building ultra-thin and flexible batteries,which could further expand the application scenarios of high-energy rechargeable LMBs.In this perspective,recent progresses on ion transport mechanism of SPEs and structural designs of electrolyte components(e.g.conductive lithium salts,polymer matrices)are scrutinized.In addition,key achievements in the field of single lithium-ion conductive SPEs are also outlined,aiming to provide the status quo in those SPEs with high selectivity in cationic transport.Finally,possible strategies for improving the performance of SPEs and their rechargeable LMBs are also discussed.展开更多
Lithium (Li) metal is considered as the ultimate anode choice for developing next-generation high-energy batteries. However, the poor tolerance against moist air and the unstable solid electrolyte interphases (SEI) in...Lithium (Li) metal is considered as the ultimate anode choice for developing next-generation high-energy batteries. However, the poor tolerance against moist air and the unstable solid electrolyte interphases (SEI) induced by the intrinsic high reactivity of lithium bring series of obstacles such as the rigorous operating condition, the poor electrochemical performance, and safety anxiety of the cell, which to a large extent hinder the commercial utilization of Li metal anode. Here, an effective encapsulation strategy was reported via a facile drop-casting and a following heat-assisted cross-linking process. Benefiting from the inherent hydrophobicity and the compact micro-structure of the cross-linked poly(vinylidene-co-hex afluoropropylene) (PVDF–HFP), the as-encapsulated Li metal exhibited prominent stability toward moisture, as well corroborated by the evaluations both under the humid air at 25 °C with 30% relative humidity (RH) and pure water. Moreover, the encapsulated Li metal anode exhibits a decent electrochemical performance without substantially increasing the cell polarization due to the uniform and unblocked ion channels, which originally comes from the superior affinity of the PVDF–HFP polymer toward nonaqueous electrolyte. This work demonstrates a novel and valid encapsulation strategy for humiditysensitive alkali metal electrodes, aiming to pave the way for the large-scale and low-cost deployment of the alkali metal-based high-energy-density batteries.展开更多
Despite being widely used in people's daily life,the safety issue of lithium-ion batteries(LIBs)has become the major barrier for them to be applied in electrical vehicles(EVs)or large-scale energy storage.Typicall...Despite being widely used in people's daily life,the safety issue of lithium-ion batteries(LIBs)has become the major barrier for them to be applied in electrical vehicles(EVs)or large-scale energy storage.Typically,due to the use of liquid electrolytes containing flammable solvents which are easily oxidized by excessive and accumulated heat,the potential thermal runaway is a major safety concern for traditional LIBs.A strategy for a safer electrolyte design is controlling the flammability and volatility of the liquid electro-lytes,to effectively prevent thermal runaway,thus avoiding fire or other risks.Through this study,the mechanisms of thermal runa-way and the recent progress in electrolyte engineering toward LIBs were summarized,covering the major strategies including adding flame-retardants,the utilization of ionic liquid electrolytes and solid electrolytes.The characteristics,strengths and weaknesses of different strategies were discussed.New designing directions of safer electrolytes for the LIBs were also provided.展开更多
Ionic liquids(ILs)have been deemed as promising electrolyte materials for building safer and highly-performing rechargeable lithium batteries,owing to their negligible volatility,low-flammability,and high thermal stab...Ionic liquids(ILs)have been deemed as promising electrolyte materials for building safer and highly-performing rechargeable lithium batteries,owing to their negligible volatility,low-flammability,and high thermal stability,etc.The profound structural designability of IL cations and anions allows relatively facile regulations of their key physical(e.g.,viscosities,and ionic conductivities)and electrochemical(e.g.,anodic,and cathodic stabilities)properties,and therefore fulfills the critical requirements stipulated by various battery configurations.In this review,a historical overview on the development of ILs for nonaqueous electrolytes is provided,and the correlations between chemical structures and the basic properties of ILs are discussed.Furthermore,the key achievements in the field of IL-based electrolytes are scrutinized,including liquid electrolytes,polymer electrolytes,and composite polymer electrolytes.Based on literature reports and our previous work in this field,possible strategies to improve the performance of IL-based electrolytes and their rechargeable batteries are discussed.The present work not only provides the status quo in the development of IL-based electrolytes but also inspires the structural design of ILs for other kinds of rechargeable batteries(e.g.,sodium,potassium,zinc batteries).展开更多
Compared with commercial lithium batteries with liquid electrolytes,all-solidstate lithium batteries(ASSLBs)possess the advantages of higher safety,better electrochemical stability,higher energy density,and longer cyc...Compared with commercial lithium batteries with liquid electrolytes,all-solidstate lithium batteries(ASSLBs)possess the advantages of higher safety,better electrochemical stability,higher energy density,and longer cycle life;therefore,ASSLBs have been identified as promising candidates for next-generation safe and stable high-energy-storage devices.The design and fabrication of solid-state electrolytes(SSEs)are vital for the future commercialization of ASSLBs.Among various SSEs,solid polymer composite electrolytes(SPCEs)consisting of inorganic nanofillers and polymer matrix have shown great application prospects in the practice of ASSLBs.The incorporation of inorganic nanofillers into the polymer matrix has been considered as a crucial method to achieve high ionic conductivity for SPCE.In this review,the mechanisms of Li+transport variation caused by incorporating inorganic nanofillers into the polymer matrix are discussed in detail.On the basis of the recent progress,the respective contributions of polymer chains,passive ceramic nanofillers,and active ceramic nanofillers in affecting the Li+transport process of SPCE are reviewed systematically.The inherent relationship between the morphological characteristics of inorganic nanofillers and the ionic conductivity of the resultant SPCE is discussed.Finally,the challenges and future perspectives for developing high-performance SPCE are put forward.This review aims to provide possible strategies for the further improvement of ionic conductivity in inorganic nanoscale filler-reinforced SPCE and highlight their inspiration for future research directions.展开更多
Solid polymer electrolytes(SPEs)have become increasingly attractive in solid-state lithium-ion batteries(SSLIBs)in recent years because of their inherent properties of flexibility,processability,and interfacial compat...Solid polymer electrolytes(SPEs)have become increasingly attractive in solid-state lithium-ion batteries(SSLIBs)in recent years because of their inherent properties of flexibility,processability,and interfacial compatibility.However,the commercialization of SPEs remains challenging for flexible and high-energy-density LIBs.The incorporation of functional additives into SPEs could significantly improve the electrochemical and mechanical properties of SPEs and has created some historical milestones in boosting the development of SPEs.In this study,we review the roles of additives in SPEs,highlighting the working mechanisms and functionalities of the additives.The additives could afford significant advantages in boosting ionic conductivity,increasing ion transference number,improving high-voltage stability,enhancing mechanical strength,inhibiting lithium dendrite,and reducing flammability.Moreover,the application of functional additives in high-voltage cathodes,lithium-sulfur batteries,and flexible lithiumion batteries is summarized.Finally,future research perspectives are proposed to overcome the unresolved technical hurdles and critical issues in additives of SPEs,such as facile fabrication process,interfacial compatibility,investigation of the working mechanism,and special functionalities.展开更多
Solid polymer electrolytes(SPEs)with high ionic conductivity are desirable for solid-state lithium metal batteries(SSLMBs)to achieve enhanced safety and energy density.Incorporating nanofillers into a polymeric matrix...Solid polymer electrolytes(SPEs)with high ionic conductivity are desirable for solid-state lithium metal batteries(SSLMBs)to achieve enhanced safety and energy density.Incorporating nanofillers into a polymeric matrix to develop nanocomposite solid electrolytes(NCSEs)has become a promising method for improving the ionic conductivity of the SPEs.Here,a novel ZIF-8-functionalized NCSE was prepared for high-temperature S SLMB s using an in situ radical polymerization method.It is found that the ZIF-8 nanoparticles could reduce the crystallinity of polymer segments and offer a Lewis acid surface that promotes the dissociation of lithium bis(trifluoromethanesulfonyl)imide(LiTFSI)and stabilizes the TFSI^(-) anion movement.Thus,the as-prepared NCSE exhibits an outstanding ionic conductivity of 1.63×10^(-3)S·cm^(-1),an electrochem ical stability window of 5.0 V at 80℃,and excellent interface compatibility with lithium metal anode with a stable polarization over 2000 h.Furthermore,the assembled SSLMBs with LiFePO_(4)cathode show dendrite-free Li-metal surface,good rate capability,and stable cycling stability with a capacity retention of 70%over 1000 cycles at a high temperature of 80℃.This work provides valuable insights into promoting the ionic conductivity of SPEs.展开更多
High-voltage lithium metal batteries(LMBs)have been considered promising next-generation highenergy-density batteries.However,commercial carbonate electrolytes can scarcely be employed in LMBs owing to their poor comp...High-voltage lithium metal batteries(LMBs)have been considered promising next-generation highenergy-density batteries.However,commercial carbonate electrolytes can scarcely be employed in LMBs owing to their poor compatibility with metallic lithium.N,N-dimethylacrylamide(DMAA)-a crosslinkable solubilizer with a high Gutmann donor number-is employed to facilitate the dissolution of insoluble lithium nitrate(LiNO3)in carbonate-based electrolytes and to form gel polymer electrolytes(GPEs)through in situ polymerization.The Lit solvation structure of the GPEs is regulated using LiNO3 and DMAA,which suppresses the decomposition of LiPFe and facilitates the formation of an inorganic-rich solid electrolyte interface.Consequently,the Coulombic efficiency(CE)of the LillCu cell assembled with a GPE increases to 98.5%at room temperature,and the high-voltage LillNCM622 cell achieves a capacity retention of 80.1%with a high CE of 99.5%after 400 cycles.The bifunctional polymer electrolytes are anticipated to pave the way for next-generation high-voltage LMBs.展开更多
Solid-state lithium metal batteries(SSLMBs)are considered an auspicious technology to develop high energy density and safe energy storage devices.The double layer polymer electrolyte(DLPE)is a rational approach for en...Solid-state lithium metal batteries(SSLMBs)are considered an auspicious technology to develop high energy density and safe energy storage devices.The double layer polymer electrolyte(DLPE)is a rational approach for engineering high-performance SSLMBs addressing electrolyte requirements with specifically designed polymers at the positive electrode and as separator.In this work,SSLMBs were assembled with poly(propylene carbonate)(PPC),offering stability toward oxidation at the positive electrode,and a gel polymer electrolyte with polyethyleneglycol dimethylether(PEGDME)as separator,offering high ionic conductivity at low temperature and sufficient interfacial stability with Li metal.The electrochemical properties and performance of cells with LiFePO_(4) and Li[Ni_(0.6)Mn_(0.2)Co_(0.2)]O_(2) positive electrodes are thoroughly investigated as function of the operating temperature by using a host of characterization techniques.High-voltage cells with an areal capacity of 0.7 mAh·cm^(−2)cycled at 40℃ exhibit a higher capacity retention than the cells cycled at 70℃.To understand such differences,a three-electrode setup is applied to discriminate anodic processes from cathodic as function of the temperature.We elucidate the ageing and interfacial evolution for DLPE cells with gel polymer electrolytes paving the way for building performance solid state batteries.展开更多
文摘Solid polymer electrolytes are light-weight, flexible, and non-flammable and provide a feasible solution to the safety issues facing lithium-ion batteries through the replacement of organic liquid electrolytes. Substantial research efforts have been devoted to achieving the next generation of solid-state polymer lithium batteries. Herein, we provide a review of the development of solid polymer electrolytes and provide comprehensive insights into emerging developments. In particular, we discuss the different molecular structures of the solid polymer matrices, including polyether, polyester, polyacrylonitrile, and polysiloxane, and their interfacial compatibility with lithium, as well as the factors that govern the properties of the polymer electrolytes. The discussion aims to give perspective to allow the strategic design of state-of-the-art solid polymer electrolytes, and we hope it will provide clear guidance for the exploration of high-performance lithium batteries.
基金Beijing National Laboratory for Molecular Sciences,Grant/Award Number:2019BMS20022National Natural Science Foundation of China,Grant/Award Number:22005314+3 种基金Strategic Priority Research Program of the Chinese Academy of Sciences,Grant/Award Number:XDA21070300The China Postdoctoral Science Foundation,Grant/Award Number:2019M660805The National Key R&D Program of China,Grant/Award Number:2019YFA0705600The Special Financial Grant from the China Postdoctoral Science Foundation,Grant/Award Number:2020T130658。
文摘Conventional lithium-ion batteries(LIBs)with graphite anodes are approaching their theoretical limitations in energy density.Replacing the conventional graphite anodes with high-capacity Si-based anodes represents one of the most promising strategies to greatly boost the energy density of LIBs.However,the inherent huge volume expansion of Si-based materials after lithiation and the resulting series of intractable problems,such as unstable solid electrolyte interphase layer,cracking of electrode,and especially the rapid capacity degradation of cells,severely restrict the practical application of Sibased anodes.Over the past decade,numerous reports have demonstrated that polymer binders play a critical role in alleviating the volume expansion and maintaining the integrity and stable cycling of Si-based anodes.In this review,the state-of-the-art designing of polymer binders for Si-based anodes have been systematically summarized based on their structures,including the linear,branched,crosslinked,and conjugated conductive polymer binders.Especially,the comprehensive designing of multifunctional polymer binders,by a combination of multiple structures,interactions,crosslinking chemistries,ionic or electronic conductivities,soft and hard segments,and so forth,would be promising to promote the practical application of Si-based anodes.Finally,a perspective on the rational design of practical polymer binders for the large-scale application of Si-based anodes is presented.
基金NationalNatural Science Foundation of China,Grant/Award Numbers:51773092,21975124Research Foundation of Material-orientedChemicalEngineering StateKey Lab,Grant/Award Number:ZK201717+1 种基金FundamentalResearch Funds for the CentralUniversities,Grant/Award Number:2020kfyXJJS095Spanish Government,Grant/Award Number:MINECO RETOS/RTI2018-098301-B-I00。
文摘The interest for solid-state lithium metal(Li◦)batteries(SSLMBs)has been growing exponentially in recent years in view of their higher energy density and eliminated safety concerns.Solid polymer electrolytes(SPEs)are soft ionic conductors which can be easily processed into thin films at industrial level;these unique features confer solid-state Li◦polymer batteries(SSLMPBs,i.e.,SSLMBs utilizing SPEs as electrolytes)distinct advantages compared to SSLMBs containing other electrolytes.In this article,we briefly review recent progresses and achievements in SSLMPBs including the improvement of ionic conductivity of SPEs and their interfacial stability with Li◦anode.Moreover,we outline several advanced in-situ and ex-situ characterizing techniques which could assist in-depth understanding of the anode-electrolyte interphases in SSLMPBs.This article is hoped not only to update the state-of-the-art in the research on SSLMPBs but also to bring intriguing insights that could improve the fundamental properties(e.g.,transport,dendrite formation,and growth,etc.)and electrochemical performance of SSLMPBs.
基金the Foundation of Science and Technology Department of Heibei Province (No. 05547003D-4)the Foundation of the Education Department of Hebei Province, China (No. 2005356).
文摘Lithium/polypyrrole （Li/PPy） batteries were fabricated using lithium sheet as cathode, PPy as anode, microporous membrane polypropylene/polyethylene/polypropylene （PP/PE/PP） composite as separator and LiPF6/ethylene carbonate-dimethyl carbonate-methyl ethyl carbonate （EC-DMC-EMC） as electrolyte. Polypyrrole was prepared by chemical polymerization. Certain fundamental electrochemical performances were investigated. Properties of the batteries were characterized and tested by SEM, galvanostatic charge/discharge tests, cyclic voltammetry （CV）, and a.c. impedance spectroscopy. The influences of separator, morphology, and conductivity of PPy anode, cold-molded pressure, and electric current on the performances of the batteries were studied. Using PP/PE/PP membranes as separator, the battery showed good storage stability and cycling property. The conductivity of materials rather than morphology affected the behavior of the battery. The higher the conductivity, the better performances the cells had. Proper cold-molded pressure 20 MPa of the anode pellet would make the properties of the cells good and the fitted charge/discharge current was 0.1 mA. The cells showed excellent performance with 97%-100% coulombic efficiency. The highest discharge capacity of 95.2 mAh/g was obtained.
基金The authors gratefully acknowledge the financial support provided by the Fundamental Research Funds for Central Universities,HUST(2020kfyXJJS095).
文摘Solid polymer electrolytes(SPEs)possess several merits including no leakage,ease in process,and suppressing lithium dendrites growth.These features are beneficial for improving the cycle life and safety performance of rechargeable lithium metal batteries(LMBs),as compared to conventional non-aqueous liquid electrolytes.Particularly,the superior elasticity of polymeric material enables the employment of SPEs in building ultra-thin and flexible batteries,which could further expand the application scenarios of high-energy rechargeable LMBs.In this perspective,recent progresses on ion transport mechanism of SPEs and structural designs of electrolyte components(e.g.conductive lithium salts,polymer matrices)are scrutinized.In addition,key achievements in the field of single lithium-ion conductive SPEs are also outlined,aiming to provide the status quo in those SPEs with high selectivity in cationic transport.Finally,possible strategies for improving the performance of SPEs and their rechargeable LMBs are also discussed.
基金This work was supported by National Key Research and Development Program(2016YFA0202500)National Natural Science Foundation of China(21776019)Beijing Natural Science Foundation(L182021).
文摘Lithium (Li) metal is considered as the ultimate anode choice for developing next-generation high-energy batteries. However, the poor tolerance against moist air and the unstable solid electrolyte interphases (SEI) induced by the intrinsic high reactivity of lithium bring series of obstacles such as the rigorous operating condition, the poor electrochemical performance, and safety anxiety of the cell, which to a large extent hinder the commercial utilization of Li metal anode. Here, an effective encapsulation strategy was reported via a facile drop-casting and a following heat-assisted cross-linking process. Benefiting from the inherent hydrophobicity and the compact micro-structure of the cross-linked poly(vinylidene-co-hex afluoropropylene) (PVDF–HFP), the as-encapsulated Li metal exhibited prominent stability toward moisture, as well corroborated by the evaluations both under the humid air at 25 °C with 30% relative humidity (RH) and pure water. Moreover, the encapsulated Li metal anode exhibits a decent electrochemical performance without substantially increasing the cell polarization due to the uniform and unblocked ion channels, which originally comes from the superior affinity of the PVDF–HFP polymer toward nonaqueous electrolyte. This work demonstrates a novel and valid encapsulation strategy for humiditysensitive alkali metal electrodes, aiming to pave the way for the large-scale and low-cost deployment of the alkali metal-based high-energy-density batteries.
基金supported by the Australian Research Council discovery project,grant Nos.DP200103332,DP200103315.
文摘Despite being widely used in people's daily life,the safety issue of lithium-ion batteries(LIBs)has become the major barrier for them to be applied in electrical vehicles(EVs)or large-scale energy storage.Typically,due to the use of liquid electrolytes containing flammable solvents which are easily oxidized by excessive and accumulated heat,the potential thermal runaway is a major safety concern for traditional LIBs.A strategy for a safer electrolyte design is controlling the flammability and volatility of the liquid electro-lytes,to effectively prevent thermal runaway,thus avoiding fire or other risks.Through this study,the mechanisms of thermal runa-way and the recent progress in electrolyte engineering toward LIBs were summarized,covering the major strategies including adding flame-retardants,the utilization of ionic liquid electrolytes and solid electrolytes.The characteristics,strengths and weaknesses of different strategies were discussed.New designing directions of safer electrolytes for the LIBs were also provided.
基金supported from the Fundamental Research Funds for the Central Universities,HUST (2020kfyXJJS095)the National Natural Science Foundation of China (52203223 and 22279037)。
文摘Ionic liquids(ILs)have been deemed as promising electrolyte materials for building safer and highly-performing rechargeable lithium batteries,owing to their negligible volatility,low-flammability,and high thermal stability,etc.The profound structural designability of IL cations and anions allows relatively facile regulations of their key physical(e.g.,viscosities,and ionic conductivities)and electrochemical(e.g.,anodic,and cathodic stabilities)properties,and therefore fulfills the critical requirements stipulated by various battery configurations.In this review,a historical overview on the development of ILs for nonaqueous electrolytes is provided,and the correlations between chemical structures and the basic properties of ILs are discussed.Furthermore,the key achievements in the field of IL-based electrolytes are scrutinized,including liquid electrolytes,polymer electrolytes,and composite polymer electrolytes.Based on literature reports and our previous work in this field,possible strategies to improve the performance of IL-based electrolytes and their rechargeable batteries are discussed.The present work not only provides the status quo in the development of IL-based electrolytes but also inspires the structural design of ILs for other kinds of rechargeable batteries(e.g.,sodium,potassium,zinc batteries).
基金the National Natural Science Foundation of China(Grant No.21673051)the Department of Science and Technology of Guangdong Province,China(No.2019A050510043).
文摘Compared with commercial lithium batteries with liquid electrolytes,all-solidstate lithium batteries(ASSLBs)possess the advantages of higher safety,better electrochemical stability,higher energy density,and longer cycle life;therefore,ASSLBs have been identified as promising candidates for next-generation safe and stable high-energy-storage devices.The design and fabrication of solid-state electrolytes(SSEs)are vital for the future commercialization of ASSLBs.Among various SSEs,solid polymer composite electrolytes(SPCEs)consisting of inorganic nanofillers and polymer matrix have shown great application prospects in the practice of ASSLBs.The incorporation of inorganic nanofillers into the polymer matrix has been considered as a crucial method to achieve high ionic conductivity for SPCE.In this review,the mechanisms of Li+transport variation caused by incorporating inorganic nanofillers into the polymer matrix are discussed in detail.On the basis of the recent progress,the respective contributions of polymer chains,passive ceramic nanofillers,and active ceramic nanofillers in affecting the Li+transport process of SPCE are reviewed systematically.The inherent relationship between the morphological characteristics of inorganic nanofillers and the ionic conductivity of the resultant SPCE is discussed.Finally,the challenges and future perspectives for developing high-performance SPCE are put forward.This review aims to provide possible strategies for the further improvement of ionic conductivity in inorganic nanoscale filler-reinforced SPCE and highlight their inspiration for future research directions.
基金supported by the Australian Research Council(ARC)Discovery Projects(DP210103266 and DP1701048343)the Griffith University Ph.D.Scholarships.
文摘Solid polymer electrolytes(SPEs)have become increasingly attractive in solid-state lithium-ion batteries(SSLIBs)in recent years because of their inherent properties of flexibility,processability,and interfacial compatibility.However,the commercialization of SPEs remains challenging for flexible and high-energy-density LIBs.The incorporation of functional additives into SPEs could significantly improve the electrochemical and mechanical properties of SPEs and has created some historical milestones in boosting the development of SPEs.In this study,we review the roles of additives in SPEs,highlighting the working mechanisms and functionalities of the additives.The additives could afford significant advantages in boosting ionic conductivity,increasing ion transference number,improving high-voltage stability,enhancing mechanical strength,inhibiting lithium dendrite,and reducing flammability.Moreover,the application of functional additives in high-voltage cathodes,lithium-sulfur batteries,and flexible lithiumion batteries is summarized.Finally,future research perspectives are proposed to overcome the unresolved technical hurdles and critical issues in additives of SPEs,such as facile fabrication process,interfacial compatibility,investigation of the working mechanism,and special functionalities.
基金financially supported by the Fundamental Research Program of Shanxi Province(No.202103021224177)the Science and Technology Cooperation and Exchange Special Project of Shanxi Province(No.202204041101005)+1 种基金the Key Laboratory Research Foundation of North University of China and Shanxi Key Laboratory of Advanced Carbon Electrode Materials(No.202104010910019)the funding support from the Australian Research Council(No.DP200102573)。
文摘Solid polymer electrolytes(SPEs)with high ionic conductivity are desirable for solid-state lithium metal batteries(SSLMBs)to achieve enhanced safety and energy density.Incorporating nanofillers into a polymeric matrix to develop nanocomposite solid electrolytes(NCSEs)has become a promising method for improving the ionic conductivity of the SPEs.Here,a novel ZIF-8-functionalized NCSE was prepared for high-temperature S SLMB s using an in situ radical polymerization method.It is found that the ZIF-8 nanoparticles could reduce the crystallinity of polymer segments and offer a Lewis acid surface that promotes the dissociation of lithium bis(trifluoromethanesulfonyl)imide(LiTFSI)and stabilizes the TFSI^(-) anion movement.Thus,the as-prepared NCSE exhibits an outstanding ionic conductivity of 1.63×10^(-3)S·cm^(-1),an electrochem ical stability window of 5.0 V at 80℃,and excellent interface compatibility with lithium metal anode with a stable polarization over 2000 h.Furthermore,the assembled SSLMBs with LiFePO_(4)cathode show dendrite-free Li-metal surface,good rate capability,and stable cycling stability with a capacity retention of 70%over 1000 cycles at a high temperature of 80℃.This work provides valuable insights into promoting the ionic conductivity of SPEs.
基金supported by the National Natural Science Foundation of China(51971250)China Postdoctoral Science Foundation(2023M733933)+1 种基金the Natural Science Foundation of Hunan Province(2023J40759)the State Key Laboratory of Powder Metallurgy at Central South University.
文摘High-voltage lithium metal batteries(LMBs)have been considered promising next-generation highenergy-density batteries.However,commercial carbonate electrolytes can scarcely be employed in LMBs owing to their poor compatibility with metallic lithium.N,N-dimethylacrylamide(DMAA)-a crosslinkable solubilizer with a high Gutmann donor number-is employed to facilitate the dissolution of insoluble lithium nitrate(LiNO3)in carbonate-based electrolytes and to form gel polymer electrolytes(GPEs)through in situ polymerization.The Lit solvation structure of the GPEs is regulated using LiNO3 and DMAA,which suppresses the decomposition of LiPFe and facilitates the formation of an inorganic-rich solid electrolyte interface.Consequently,the Coulombic efficiency(CE)of the LillCu cell assembled with a GPE increases to 98.5%at room temperature,and the high-voltage LillNCM622 cell achieves a capacity retention of 80.1%with a high CE of 99.5%after 400 cycles.The bifunctional polymer electrolytes are anticipated to pave the way for next-generation high-voltage LMBs.
文摘Solid-state lithium metal batteries(SSLMBs)are considered an auspicious technology to develop high energy density and safe energy storage devices.The double layer polymer electrolyte(DLPE)is a rational approach for engineering high-performance SSLMBs addressing electrolyte requirements with specifically designed polymers at the positive electrode and as separator.In this work,SSLMBs were assembled with poly(propylene carbonate)(PPC),offering stability toward oxidation at the positive electrode,and a gel polymer electrolyte with polyethyleneglycol dimethylether(PEGDME)as separator,offering high ionic conductivity at low temperature and sufficient interfacial stability with Li metal.The electrochemical properties and performance of cells with LiFePO_(4) and Li[Ni_(0.6)Mn_(0.2)Co_(0.2)]O_(2) positive electrodes are thoroughly investigated as function of the operating temperature by using a host of characterization techniques.High-voltage cells with an areal capacity of 0.7 mAh·cm^(−2)cycled at 40℃ exhibit a higher capacity retention than the cells cycled at 70℃.To understand such differences,a three-electrode setup is applied to discriminate anodic processes from cathodic as function of the temperature.We elucidate the ageing and interfacial evolution for DLPE cells with gel polymer electrolytes paving the way for building performance solid state batteries.
