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
Silicon(Si)is a promising anode material for lithium‐ion batteries(LIBs)owing to its tremendously high theoretical storage capacity(4200 mAh g−1),which has the potential to elevate the energy of LIBs.However,Si anode...Silicon(Si)is a promising anode material for lithium‐ion batteries(LIBs)owing to its tremendously high theoretical storage capacity(4200 mAh g−1),which has the potential to elevate the energy of LIBs.However,Si anodes exhibit severe volume change during lithiation/delithiation processes,resulting in anode pulverization and delamination with detrimental growth of solid electrolyte interface layers.As a result,the cycling stability of Si anodes is insufficient for commercialization in LIBs.Polymeric binders can play critical roles in Si anodes by affecting their cycling stability,although they occupy a small portion of the electrodes.This review introduces crucial factors influencing polymeric binders'properties and the electrochemical performance of Si anodes.In particular,we emphasize the structure–property relationships of binders in the context of molecular design strategy,functional groups,types of interactions,and functionalities of binders.Furthermore,binders with additional functionalities,such as electrical conductivity and self‐healability,are extensively discussed,with an emphasis on the binder design principle.展开更多
Research on the chemistry of high-energy-density transition metal oxide cathodes(TMOCs)is at the forefront in the pursuit of lithium-ion batteries with increased energy density.As a critical component of these cathode...Research on the chemistry of high-energy-density transition metal oxide cathodes(TMOCs)is at the forefront in the pursuit of lithium-ion batteries with increased energy density.As a critical component of these cathodes,binders not only glue cathode active material particles and conducting carbons together and to current collectors but also play pivotal roles in building multiscale compatible interphases between electrolytes and cathodes.In this review,we outline several vital design considerations of high-voltage binders,several of which are already present in traditional binder design that need to be highlighted,and systematically reveal the chemistry and mechanisms underpinning such binders for in-depth understanding.Further optimization of the design of polymer binders to improve battery performance is also discussed.Finally,perspec-tives regarding the future rational design and promising research opportunities of state-of-the-art binders for high-voltage TMOCs are presented.展开更多
The increasing demand for short charging time on electric vehicles has motivated realization of fast chargeable lithium-ion batteries(LIBs).However,shortening the charging time of LIBs is limited by Li^(+)intercalatio...The increasing demand for short charging time on electric vehicles has motivated realization of fast chargeable lithium-ion batteries(LIBs).However,shortening the charging time of LIBs is limited by Li^(+)intercalation process consisting of liquid-phase diffusion,de-solvation,SEI crossing,and solid-phase diffusion.Herein,we propose a new strategy to accelerate the de-solvation step through a control of interaction between polymeric binder and solvent-Li^(+)complexes.For this purpose,three alkali metal ions(Li^(+),Na^(+),and K^(+))substituted carboxymethyl cellulose(Li-,Na-,and K-CMC)are prepared to examine the effects of metal ions on their performances.The lowest activation energy of de-solvation and the highest chemical diffusion coefficient were observed for Li-CMC.Specifically,Li-CMC cell with a capacity of 3 mAh cm^(-2)could be charged to>95%in 10 min,while a value above>85%was observed after 150 cycles.Thus,the presented approach holds great promise for the realization of fast charging.展开更多
Silicon(Si)is considered one of the most promising anode materials for next-generation lithium-ion batteries due to its ultrahigh theoretical capacity.However,its application is significantly limited by severe volume ...Silicon(Si)is considered one of the most promising anode materials for next-generation lithium-ion batteries due to its ultrahigh theoretical capacity.However,its application is significantly limited by severe volume expansion,leading to structural degradation and poor cycling stability.Polymer binders play a critical role in addressing these issues by providing mechanical stabilization.Inspired by the mechanically adaptive architecture of spider webs,where stiff radial threads and extensible spiral threads act in synergy,a dual-thread architecture polymer binder(PALT)with energy dissipation ability enabled by integrating rigid and flexible domains is designed.The rigid poly(acrylic acid lithium)(PAALi)segments offer structural reinforcement,while the soft segments(poly(lipoic acid-tannic acid),LT)introduce dynamic covalent bonds and multiple hydrogen bonds that function as reversible sacrificial bonds,enhancing energy dissipation during cycling.Comprehensive experimental and computational analyses demonstrate effectively reduced stress concentration,improved structural integrity,and stable electrochemical performance over prolonged cycling.The silicon anode incorporating the PALT binder exhibits a satisfying capacity loss per cycle of 0.042% during 350 charge/discharge cycles at 3580 m A g^(-1).This work highlights a bioinspired binder design strategy that combines intrinsic rigidity with dynamic stress adaptability to advance the mechanical and electrochemical stability of silicon anodes.展开更多
The objective of this research was to show a way to conduct rejuvenation of aged polymer modified asphalt binder（PMB） successfully.To fully evaluate and understand the rejuvenation of aged PMB,the Penetration grade ...The objective of this research was to show a way to conduct rejuvenation of aged polymer modified asphalt binder（PMB） successfully.To fully evaluate and understand the rejuvenation of aged PMB,the Penetration grade tests including penetration,soften point,ductility and elastic recovery and SuperpaveTM PG grade tests including DSR,BBR and DDT were conducted.The rejuvenation effect of aged PMB by utilizing a fluid recycling agent in common use for binder rejuvenation was evaluated.And then the compound rejuvenation effect of aged PMB by utilizing the recycling agent with a new modifying additive for binder modification was evaluated.The experimental results indicated that the recycling agent in common use currently does not apply to polymer modified asphalt binder rejuvenation.But the recycling agent together with the modifying additive can restore the characteristics of aged polymer modified binder very well.Therefore,compound rejuvenation of polymer modified asphalt binder is recommended.展开更多
Nickel-rich layered oxide LiNi_(1-x-y)Co_(x)Al_yO_(2)(NCA) with high theoretical capacity is a promising cathode material for the next-generation high-energy batteries.However,it undergoes a rapid capacity fading when...Nickel-rich layered oxide LiNi_(1-x-y)Co_(x)Al_yO_(2)(NCA) with high theoretical capacity is a promising cathode material for the next-generation high-energy batteries.However,it undergoes a rapid capacity fading when operating at high temperature due to the accelerated cathode/electrolyte interfacial reactions and adhesive efficacy loss of conventional polyvinylideneffuoride(PVdF) binder.Herein,poly(acrylonitrile-co-methyl acrylate) copolymer is designed with electron-rich-C≡N groups as a novel binder for LiNi_(0.8)Co_(0.1)Al_(0.1)O_(2) cathode at high temperature.The electron-rich-C≡N groups are able to coordinate with the active Ni^(3+) on the surface of NCA,alleviating electrolyte decomposition and cathode structure degradation.Moreover,the strong adhesive ability is conducive to maintain integrity of electrodes upon cycling at 55℃.In consequence,the NCA electrodes with this functional binder display improved cycling stability(81.5% capacity retention after 100 cycles) and rate performance at 55℃.展开更多
The lithium-sulfur(Li-S)battery is one of the most promising substitutes for current energy storage systems because of its low cost,high theoretical capacity,and high energy density.However,the high solubility of inte...The lithium-sulfur(Li-S)battery is one of the most promising substitutes for current energy storage systems because of its low cost,high theoretical capacity,and high energy density.However,the high solubility of intermediate products(i.e.,lithium polysulfides)and the resultant shuttle effect lead to rapidly fading capacity and a low coulombic efficiency,which hinder the practical application of Li-S batteries.In this study,block copolymers are constructed with both an ethylene oxide unit and a styrene unit and then used as binders for Li-S batteries.Electrochemical performance improvements are attributed to the synergistic effects contributed by the different units of the block copolymer.The ethylene oxide unit traps polysulfide,which bonds strongly with the intermediate lithium polysulfide,and enhances the transport of lithium ions to reach high capacity.Meanwhile,the styrene unit maintains cathode integrity by improving the mechanical properties and elasticity of the constructed block copolymer to accommodate the large volume changes.By enabling multiple functions via different units in the polymer chain,high sulfur utilization is achieved,polysulfide diffusion is confined,and the shuttle effect is suppressed during the cycle life of Li-S batteries,as revealed by operando ultraviolet-visible spectroscopy and S Kedge X-ray absorption spectroscopy.展开更多
An experiment was performed to study the influence of polymer binders on the physical properties,and stability against a simulated rainfall,of a slope consisting of engineering spoil.Results showed that low polymer bi...An experiment was performed to study the influence of polymer binders on the physical properties,and stability against a simulated rainfall,of a slope consisting of engineering spoil.Results showed that low polymer binder concentrations(≤500g/m3) could enhance the air permeability and moisture-retaining capacity of the engineering spoil;however,adding more polymer binder made the hardness of the engineering spoil increase and then decline.With the increase of polymer binder concentrations,the surface(0-5cm) permeability of the engineering spoil decreased but the permeability of the lower layers(5-10cm) increased.Polymer binders might reduce runoff and sediment,but the effect becomes weaker with the increase of rainfall.The results of this study have significance for engineering practices.Further experiments are needed to study the effects of binders under other conditions,such as natural rainfall,different slopes,different rock types,different degrees and spoil weathering and different added material,and the chemical interaction between soil and polymer binders.展开更多
The intrinsic volume changes(about 300%)of Si anode during the lithiation/delithiation leads to the serious degradation of battery performance despite of theoretical capacity of 3579 mAh g^(-1) of Si.Herein,a three-di...The intrinsic volume changes(about 300%)of Si anode during the lithiation/delithiation leads to the serious degradation of battery performance despite of theoretical capacity of 3579 mAh g^(-1) of Si.Herein,a three-dimensional(3D)conductive polymer binder with adjustable crosslinking density has been designed by employing citric acid(CA)as a crosslinker between the carboxymethyl cellulose(CMC)and the poly(3,4-ethylenedioxythiophene)poly-(styrene-4-sulfonate)(PEDOT:PSS)to stabilize Si anode.By adjusting the crosslinking density,the binder can achieve a balance between rigidity and flexibility to adapt the volume expansion upon lithiation and reversible volume recovery after delithiation of Si.Therefore,Si/CMC-CA-PEDOT:PSS(Si/CCP)electrode demonstrates an excellent performance with high capacities of 2792.3 mAh g^(-1) at 0.5 A g^(-1) and a high area capacity above 2.6 mAh cm^(-2) under Si loading of 1.38 mg cm^(-2).The full cell Si/CCP paired with Li(Ni_(0.8)Co_(0.1)Mn_(0.1))O_(2) cathode discharges a capacity of 199.0 mAh g^(-1) with 84.3%ICE at 0.1 C and the capacity retention of 95.6%after 100 cycles.This work validates the effectiveness of 3D polymer binder and provides new insights to boost the performance of Si anode.展开更多
Lithium-sulfur(Li-S)batteries are promising next-generation high energy density batteries but their practical application is hindered by several key problems,such as the intermediate polysulfide shuttling and the elec...Lithium-sulfur(Li-S)batteries are promising next-generation high energy density batteries but their practical application is hindered by several key problems,such as the intermediate polysulfide shuttling and the electrode degradation caused by the sulfur volume changes.Binder acts as one of the most essential components to build the electrodes of Li-S batteries,playing vital roles in improving the performance and maintaining the integrity of the cathode structure during cycling,especially those with high sulfur loadings.To date,tremendous efforts have been devoted to improving the properties of binders,in terms of the viscosity,elasticity,stability,toughness and conductivity,by optimizing the composition and structure of polymer binders.Moreover,the binder modification endows them strong polysulfide trapping ability to suppress the shuttling and decreases the swelling to maintain the porous structure of cathode.In this review,we summarize the recent progress on the binders for Li-S batteries and discuss the various routes,including the binder combination use,functionalization,in-situ polymerization and ion cross-linking,etc.,to enhance their performance in stabilizing the cathode,building the high sulfur loading electrode and improving the cyclic stability.At last,the design principles and the problems in further applications are also highlighted.展开更多
Rutting is one of the most damages in the asphalt surfaces for the orthotropic steel bridge decks. With Hamburg wheel tracking device, the suitable test conditions for Gussasphalt in Germany are pointed out, the high ...Rutting is one of the most damages in the asphalt surfaces for the orthotropic steel bridge decks. With Hamburg wheel tracking device, the suitable test conditions for Gussasphalt in Germany are pointed out, the high temperature behaviour of Gussasphalt with different binders are tested and compared. The polymer modified binder has higher resistance stability to rutting. The retained time and mixed frequency have obvious effects on Gussasphalt behaviour during Gussasphalt retained period.展开更多
To construct structurally stable sulfur cathode of Li-S battery with improved cycling performance,poly(acrylic acid)(PAA)crosslinked by cationic hydroxypropyl polyrotaxane(HPRN+)via dynamically reversible boronic este...To construct structurally stable sulfur cathode of Li-S battery with improved cycling performance,poly(acrylic acid)(PAA)crosslinked by cationic hydroxypropyl polyrotaxane(HPRN+)via dynamically reversible boronic ester bonds is synthesized and serves as the cathode binder.The smart polymer networks offer multifunction including buffering the volume change of the cathode during charge/discharge through the pulley effect of polyrotaxanes(PR),suppressing the shuttle effect by adsorption of polysulfide using the plentiful carboxyl,hydroxyl and quaternary ammonium cationic groups,and self-healing the micro-damages to ensure stable conduction pathways of the electrode.As a result,the Li-S batteries based on this novel multifunctional binder and simple commercial sulfur/carbon composites cathode exhibit excellent specific capacity and cycling stability.In particular,the specific capacity decay per cycle of the cell is only 0.064%along with high Coulombic efficiency after 550 cycles at 1.0 C,which is superior to most of the reported binders.Even under high sulfur loading,moreover,the cathode can deliver superior areal capacity and cycling stability.This proposed binder provides a new way for the design of high-stability sulfur cathodes.展开更多
The application of high-performance lithium-sulfur(Li-S)batteries is severely influenced by the“shuttle effect”of polysulfides and the volume change of sulfur cathode.Herein,two different polymeric binders SOT-A and...The application of high-performance lithium-sulfur(Li-S)batteries is severely influenced by the“shuttle effect”of polysulfides and the volume change of sulfur cathode.Herein,two different polymeric binders SOT-A and SOT-C with three-dimensional network structure containing polar groups(sulfhydryl groups,amide groups and amino groups)are synthesized by the nucleophilic ring-opening polymerization(ROP)of thiolactone with amino groups.The network structure formed by hydrogen bonds and functional groups can resist the volume change of the cathode.The sulfhydryl groups and the S-S bond formed by oxidative dehydrogenation of sulfhydryl group participate in the charge and discharge process of the battery as active materials,which improves the discharge specific capacity of the battery.Polar functional groups have strong chemisorption on polysulfides and effectively inhibit the“shuttle effect”.The electrochemical performances of Li-S batteries containing SOT-A and SOT-C binders are significantly enhanced.At 1 C rate,the batteries achieve initial discharge specific capacity of 871 and 837 mAh·g^(-1),respectively,and have 83.9%and 62.5%capacity retention after 500 cycles.展开更多
A mechanically strong binder with polar functional groups could overcome the dilemma of the large volume change during charge/discharge processes and poor cyclability of lithium-sulfur batteries(LSBs).In this work,for...A mechanically strong binder with polar functional groups could overcome the dilemma of the large volume change during charge/discharge processes and poor cyclability of lithium-sulfur batteries(LSBs).In this work,for the first time,we report the use of poly(thiourea triethylene glycol)(PTTG)as a multifunctional binder for sulfur cathodes to enhance the performance of LSBs.As expected,the PTTG binder facilitates the high performance and stability delivered by the Sulfur-PTTG cathode,including a higher reversible capacity of 825 mAh g^(-1) at 0.2 C after 80 cycles,a lower capacity fading(0.123%per cycle)over 350 cycles at 0.5 C,a higher areal capacity of 2.5 mAh cm^(-2) at 0.25 mA cm^(-2),and better rate capability of 587 mAh g^(-1) at 2 C.Such superior electrochemical performances could be attributed to PTTG's strong chemical adsorption towards polysulfides which may avoid the lithium polysulfide shuttle effect and excellent mechanical characteristics which prevents electrode collapse during cycling and allows the Sulfur-PTTG electrode to maintain robust electron and ion migration pathways for accelerated redox reaction kinetics.展开更多
In this study, we tried to develop the in situ coating methods of hydrophilic polymer solution containing water soluble dye on nonwoven sheet for the colorimetric film sensor. And color change of coated dye according ...In this study, we tried to develop the in situ coating methods of hydrophilic polymer solution containing water soluble dye on nonwoven sheet for the colorimetric film sensor. And color change of coated dye according to contact various gas samples (as strong acid and base, chloroform, ammonia and HF) of this dye-coated nonwoven film was examined for the application of chemically toxic materials detecting tools in the actual site of working place without aid of any kinds of detecting devices. By the addition of electron transfer agent (quinone derivatives), quick color change behaviors were observed within 10 seconds under the contact of various toxic gases in general condition(room temperature, 50% humidity).展开更多
As phase separation between the small-molecule semiconductor and the polymer binder is the key enabler of blend-based organic field-effect transistors(OFETs)fabricated by low-cost solution processing,it is crucial to ...As phase separation between the small-molecule semiconductor and the polymer binder is the key enabler of blend-based organic field-effect transistors(OFETs)fabricated by low-cost solution processing,it is crucial to understand the underlying phase separation mechanisms that determine the phase morphology,which significantly impacts device performance.Beyond the parameter space investigated in previous work,here we investigate the formation of blends by varying the branch architecture of the polymer binder and by shortening the solvent dry time using ultrasonic spray casting.The phase morphologies of the resulting blend films have been thoroughly characterized with a variety of techniques in three dimensions over multiple length scales,including AFM,energy-filtered transmission electron microscope,and neutron reflectivity,and have been correlated with electrical transport performance.From the results,we have inferred that the phase morphology is kinetically determined,limited by the inherent slow movement of polymer macromolecules.The kinetic picture,supported by molecular dynamics modeling,not only consistently explains our observations but also resolves inconsistencies in previous works.The achieved mechanistic understanding will guide further optimization of blend-based organic electronics,such as OFETs and organic photovoltaics.展开更多
The significant volume expansion(over 300%)of silicon(Si)leads to rupture and erratic regeneration of the solid electrolyte interphase(SEI),resulting in parasitic reactions and capacity degradation.While polymer binde...The significant volume expansion(over 300%)of silicon(Si)leads to rupture and erratic regeneration of the solid electrolyte interphase(SEI),resulting in parasitic reactions and capacity degradation.While polymer binders assist in the formation of stable SEI,the impact of binders on the electric double layer(EDL)structure and the mechanism underlying SEI formation at the molecular scale remains inadequately understood.In this study,we present a binder for Si anode that can modulate the initial adsorption properties and the solvent coordination behavior in EDL to achieve superior SEI.The strong affinity of the functional group for Li^(+)competes with the solvent to reduce the desolvation energy.This results in a redistribution of Li^(+)and the electrolyte solvent,decreasing free solvent content while inhibiting organic solvent reduction.The findings demonstrated that ultra-thin SEI(11 nm)consists of the inorganic inner layer and organic outer layer with high modulus and exceptional ionic conductivity,contributing to impressive capacity retention and exemplary rate performance.This work substantiates the role of binders in interfacial conditioning while providing novel insights into their practical application in silicon anode.展开更多
High-capacity metal chalcogenides often suffer from low initial coulombic efficiency(ICE)and serious capacity fading owing to the shuttle effect and volumetric expansion.Various carbon-coating and fixing methods were ...High-capacity metal chalcogenides often suffer from low initial coulombic efficiency(ICE)and serious capacity fading owing to the shuttle effect and volumetric expansion.Various carbon-coating and fixing methods were used to improve the above-mentioned performance.However,the synthesis processes of them are complex and time-consuming,limiting their engineering applications.Herein,polar polymer binder sodium polyacrylate(PAANa)is selected as an example to solve the problems of metal chalcogenides(bare micro-sized FeS)without any modification of the active materials.The special function of the polymer binder in the interface between the active material particles and the electrolytes demonstrates that a PAANa-induced network structure on the surface of ion sulfide microparticles not only buffers the mechanical stress of particles during discharging-charging,but also participates in forming a ductile solid electrolyte interphase(SEI)with high interfacial ion transportation and enhanced ICE.The cyclic stability and rate performance can be simultaneously improved.This work not only provides a new understanding of the binder on electrode,but also introduces a new way to improve the performance of batteries.展开更多
Lithium-sulfur(Li-S) batteries have shown promises for the next-generation, high-energy electrochemical storage, yet are hindered by rapid performance decay due to the polysulfide shuttle in the cathode and safety con...Lithium-sulfur(Li-S) batteries have shown promises for the next-generation, high-energy electrochemical storage, yet are hindered by rapid performance decay due to the polysulfide shuttle in the cathode and safety concerns about potential thermal runaway. To address the above challenges, herein, we show a flame-retardant cathode binder that simultaneously improves the electrochemical stability and safety of batteries. The combination of soft and hard segments in the polymer framework of binders allows high flexibility and mechanical strength for adapting to the drastic volume change during the Li(de)intercalation of the S cathode. The binder contains a large number of polar groups, which show the high affinity to polysulfides so that they help to anchor active S species at the cathode. These polar groups also help to regulate and facilitate the Li-ion transport, promoting the kinetics of polysulfide conversion reaction. The binder contains abundant phosphine oxide groups, which, in the case of battery's thermal runaway, decompose and release PO· radicals to quench the combustion reactions and stop the fire. Consequently, Li-S batteries using the new cathode binder show the improved electrochemical performance, including a low-capacity decay of 0.046% per cycle for 800 cycles at 1 C and favorable rate capabilities of up to 3 C. This work offers new insights on the practical realization of high-energy rechargeable batteries with stable storage electrochemistry and high safety.展开更多
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National Research Foundation,Grant/Award Number:2022R1A2C1092273。
文摘Silicon(Si)is a promising anode material for lithium‐ion batteries(LIBs)owing to its tremendously high theoretical storage capacity(4200 mAh g−1),which has the potential to elevate the energy of LIBs.However,Si anodes exhibit severe volume change during lithiation/delithiation processes,resulting in anode pulverization and delamination with detrimental growth of solid electrolyte interface layers.As a result,the cycling stability of Si anodes is insufficient for commercialization in LIBs.Polymeric binders can play critical roles in Si anodes by affecting their cycling stability,although they occupy a small portion of the electrodes.This review introduces crucial factors influencing polymeric binders'properties and the electrochemical performance of Si anodes.In particular,we emphasize the structure–property relationships of binders in the context of molecular design strategy,functional groups,types of interactions,and functionalities of binders.Furthermore,binders with additional functionalities,such as electrical conductivity and self‐healability,are extensively discussed,with an emphasis on the binder design principle.
基金This work was financially supported by the NSFC-Shandong Joint Fund(U1706229)the Science Foundation for the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA22010603)+1 种基金the National Natural Science Foundation of China(51803230)the Qingdao Key Laboratory of Solar Energy Utilization and Energy Storage Technology.
文摘Research on the chemistry of high-energy-density transition metal oxide cathodes(TMOCs)is at the forefront in the pursuit of lithium-ion batteries with increased energy density.As a critical component of these cathodes,binders not only glue cathode active material particles and conducting carbons together and to current collectors but also play pivotal roles in building multiscale compatible interphases between electrolytes and cathodes.In this review,we outline several vital design considerations of high-voltage binders,several of which are already present in traditional binder design that need to be highlighted,and systematically reveal the chemistry and mechanisms underpinning such binders for in-depth understanding.Further optimization of the design of polymer binders to improve battery performance is also discussed.Finally,perspec-tives regarding the future rational design and promising research opportunities of state-of-the-art binders for high-voltage TMOCs are presented.
基金supported by Electronics and Telecommunications Research Institute(ETRI)grant funded by the Korea government(20ZB1200,Development of ICT Materials,Components and Equipment Technologies)the National Research Foundation of Korea(NRF)grant funded by the Korea government(No.2020R1A4A4079810)funding from the National Research Foundation(NRF)funded by the Ministry of Science and ICT,Rep.of Korea(Project No.2021R1C1C1008776)
文摘The increasing demand for short charging time on electric vehicles has motivated realization of fast chargeable lithium-ion batteries(LIBs).However,shortening the charging time of LIBs is limited by Li^(+)intercalation process consisting of liquid-phase diffusion,de-solvation,SEI crossing,and solid-phase diffusion.Herein,we propose a new strategy to accelerate the de-solvation step through a control of interaction between polymeric binder and solvent-Li^(+)complexes.For this purpose,three alkali metal ions(Li^(+),Na^(+),and K^(+))substituted carboxymethyl cellulose(Li-,Na-,and K-CMC)are prepared to examine the effects of metal ions on their performances.The lowest activation energy of de-solvation and the highest chemical diffusion coefficient were observed for Li-CMC.Specifically,Li-CMC cell with a capacity of 3 mAh cm^(-2)could be charged to>95%in 10 min,while a value above>85%was observed after 150 cycles.Thus,the presented approach holds great promise for the realization of fast charging.
基金the National Natural Science Foundation of China(32201497)for the financial support of this research。
文摘Silicon(Si)is considered one of the most promising anode materials for next-generation lithium-ion batteries due to its ultrahigh theoretical capacity.However,its application is significantly limited by severe volume expansion,leading to structural degradation and poor cycling stability.Polymer binders play a critical role in addressing these issues by providing mechanical stabilization.Inspired by the mechanically adaptive architecture of spider webs,where stiff radial threads and extensible spiral threads act in synergy,a dual-thread architecture polymer binder(PALT)with energy dissipation ability enabled by integrating rigid and flexible domains is designed.The rigid poly(acrylic acid lithium)(PAALi)segments offer structural reinforcement,while the soft segments(poly(lipoic acid-tannic acid),LT)introduce dynamic covalent bonds and multiple hydrogen bonds that function as reversible sacrificial bonds,enhancing energy dissipation during cycling.Comprehensive experimental and computational analyses demonstrate effectively reduced stress concentration,improved structural integrity,and stable electrochemical performance over prolonged cycling.The silicon anode incorporating the PALT binder exhibits a satisfying capacity loss per cycle of 0.042% during 350 charge/discharge cycles at 3580 m A g^(-1).This work highlights a bioinspired binder design strategy that combines intrinsic rigidity with dynamic stress adaptability to advance the mechanical and electrochemical stability of silicon anodes.
基金Funded in Part by the National Natural Science Foundation of China (No. 50878054)
文摘The objective of this research was to show a way to conduct rejuvenation of aged polymer modified asphalt binder（PMB） successfully.To fully evaluate and understand the rejuvenation of aged PMB,the Penetration grade tests including penetration,soften point,ductility and elastic recovery and SuperpaveTM PG grade tests including DSR,BBR and DDT were conducted.The rejuvenation effect of aged PMB by utilizing a fluid recycling agent in common use for binder rejuvenation was evaluated.And then the compound rejuvenation effect of aged PMB by utilizing the recycling agent with a new modifying additive for binder modification was evaluated.The experimental results indicated that the recycling agent in common use currently does not apply to polymer modified asphalt binder rejuvenation.But the recycling agent together with the modifying additive can restore the characteristics of aged polymer modified binder very well.Therefore,compound rejuvenation of polymer modified asphalt binder is recommended.
基金supported by the National Natural Science Foundation of China (No. 21875181)the Natural Science Basic Research Program of Shaanxi (Program No. 2019JLP-13)+1 种基金the Shaanxi Key Research and Development Project (No. 2019TSLGY07-05)the 111 Project 2.0 (BP2018008)。
文摘Nickel-rich layered oxide LiNi_(1-x-y)Co_(x)Al_yO_(2)(NCA) with high theoretical capacity is a promising cathode material for the next-generation high-energy batteries.However,it undergoes a rapid capacity fading when operating at high temperature due to the accelerated cathode/electrolyte interfacial reactions and adhesive efficacy loss of conventional polyvinylideneffuoride(PVdF) binder.Herein,poly(acrylonitrile-co-methyl acrylate) copolymer is designed with electron-rich-C≡N groups as a novel binder for LiNi_(0.8)Co_(0.1)Al_(0.1)O_(2) cathode at high temperature.The electron-rich-C≡N groups are able to coordinate with the active Ni^(3+) on the surface of NCA,alleviating electrolyte decomposition and cathode structure degradation.Moreover,the strong adhesive ability is conducive to maintain integrity of electrodes upon cycling at 55℃.In consequence,the NCA electrodes with this functional binder display improved cycling stability(81.5% capacity retention after 100 cycles) and rate performance at 55℃.
基金supported by the Assistant Secretary for Energy Efficiency and Renewable Energy,Vehicle Technologies Office,under the Advanced Battery Materials Research(BMR)Program of the U.S.Department of Energy under Contract No.DE-AC02-05CH11231support by the U.S.Department of Energy under Contract No.106298-001+2 种基金the funding from Polish Ministry of Science and Higher Education No.1670/MOB/V/2017/0funding support of SUSTechthe resources of the National Energy Research Scientific Computing Center(NERSC)that is supported by the Office of Science of the U.S.Department of Energy。
文摘The lithium-sulfur(Li-S)battery is one of the most promising substitutes for current energy storage systems because of its low cost,high theoretical capacity,and high energy density.However,the high solubility of intermediate products(i.e.,lithium polysulfides)and the resultant shuttle effect lead to rapidly fading capacity and a low coulombic efficiency,which hinder the practical application of Li-S batteries.In this study,block copolymers are constructed with both an ethylene oxide unit and a styrene unit and then used as binders for Li-S batteries.Electrochemical performance improvements are attributed to the synergistic effects contributed by the different units of the block copolymer.The ethylene oxide unit traps polysulfide,which bonds strongly with the intermediate lithium polysulfide,and enhances the transport of lithium ions to reach high capacity.Meanwhile,the styrene unit maintains cathode integrity by improving the mechanical properties and elasticity of the constructed block copolymer to accommodate the large volume changes.By enabling multiple functions via different units in the polymer chain,high sulfur utilization is achieved,polysulfide diffusion is confined,and the shuttle effect is suppressed during the cycle life of Li-S batteries,as revealed by operando ultraviolet-visible spectroscopy and S Kedge X-ray absorption spectroscopy.
基金NSFC (National natural science foundation of China) for funding(Grant No. 30870467) this paper
文摘An experiment was performed to study the influence of polymer binders on the physical properties,and stability against a simulated rainfall,of a slope consisting of engineering spoil.Results showed that low polymer binder concentrations(≤500g/m3) could enhance the air permeability and moisture-retaining capacity of the engineering spoil;however,adding more polymer binder made the hardness of the engineering spoil increase and then decline.With the increase of polymer binder concentrations,the surface(0-5cm) permeability of the engineering spoil decreased but the permeability of the lower layers(5-10cm) increased.Polymer binders might reduce runoff and sediment,but the effect becomes weaker with the increase of rainfall.The results of this study have significance for engineering practices.Further experiments are needed to study the effects of binders under other conditions,such as natural rainfall,different slopes,different rock types,different degrees and spoil weathering and different added material,and the chemical interaction between soil and polymer binders.
基金Financial support by the NSFC no. 52371224, 51972156, and 51872131
文摘The intrinsic volume changes(about 300%)of Si anode during the lithiation/delithiation leads to the serious degradation of battery performance despite of theoretical capacity of 3579 mAh g^(-1) of Si.Herein,a three-dimensional(3D)conductive polymer binder with adjustable crosslinking density has been designed by employing citric acid(CA)as a crosslinker between the carboxymethyl cellulose(CMC)and the poly(3,4-ethylenedioxythiophene)poly-(styrene-4-sulfonate)(PEDOT:PSS)to stabilize Si anode.By adjusting the crosslinking density,the binder can achieve a balance between rigidity and flexibility to adapt the volume expansion upon lithiation and reversible volume recovery after delithiation of Si.Therefore,Si/CMC-CA-PEDOT:PSS(Si/CCP)electrode demonstrates an excellent performance with high capacities of 2792.3 mAh g^(-1) at 0.5 A g^(-1) and a high area capacity above 2.6 mAh cm^(-2) under Si loading of 1.38 mg cm^(-2).The full cell Si/CCP paired with Li(Ni_(0.8)Co_(0.1)Mn_(0.1))O_(2) cathode discharges a capacity of 199.0 mAh g^(-1) with 84.3%ICE at 0.1 C and the capacity retention of 95.6%after 100 cycles.This work validates the effectiveness of 3D polymer binder and provides new insights to boost the performance of Si anode.
基金supported by the National Natural Science Foundation of China(Nos.51772164 and U1601206)the Guangdong Natural Science Funds for Distinguished Young Scholars(2017B030306006)+2 种基金the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(2017BT01N111)the Guangdong Special Support Program(2017TQ04C664)the Shenzhen Basic Research Project(Grant Nos.JCYJ20170412171359175)
文摘Lithium-sulfur(Li-S)batteries are promising next-generation high energy density batteries but their practical application is hindered by several key problems,such as the intermediate polysulfide shuttling and the electrode degradation caused by the sulfur volume changes.Binder acts as one of the most essential components to build the electrodes of Li-S batteries,playing vital roles in improving the performance and maintaining the integrity of the cathode structure during cycling,especially those with high sulfur loadings.To date,tremendous efforts have been devoted to improving the properties of binders,in terms of the viscosity,elasticity,stability,toughness and conductivity,by optimizing the composition and structure of polymer binders.Moreover,the binder modification endows them strong polysulfide trapping ability to suppress the shuttling and decreases the swelling to maintain the porous structure of cathode.In this review,we summarize the recent progress on the binders for Li-S batteries and discuss the various routes,including the binder combination use,functionalization,in-situ polymerization and ion cross-linking,etc.,to enhance their performance in stabilizing the cathode,building the high sulfur loading electrode and improving the cyclic stability.At last,the design principles and the problems in further applications are also highlighted.
文摘Rutting is one of the most damages in the asphalt surfaces for the orthotropic steel bridge decks. With Hamburg wheel tracking device, the suitable test conditions for Gussasphalt in Germany are pointed out, the high temperature behaviour of Gussasphalt with different binders are tested and compared. The polymer modified binder has higher resistance stability to rutting. The retained time and mixed frequency have obvious effects on Gussasphalt behaviour during Gussasphalt retained period.
基金the National Natural Science Foundation of China(Nos.52033011,51873235 and 51973237)Natural Science Foundation of Guangdong Province,China(Nos.2019B1515120038 and 2021A1515010417)+1 种基金Science and Technology Planning Project of Guangdong Province(No.2020B010179001)Industry-University-Research Collaboration Project of Zhuhai City(No.ZH22017001200004PWC).
文摘To construct structurally stable sulfur cathode of Li-S battery with improved cycling performance,poly(acrylic acid)(PAA)crosslinked by cationic hydroxypropyl polyrotaxane(HPRN+)via dynamically reversible boronic ester bonds is synthesized and serves as the cathode binder.The smart polymer networks offer multifunction including buffering the volume change of the cathode during charge/discharge through the pulley effect of polyrotaxanes(PR),suppressing the shuttle effect by adsorption of polysulfide using the plentiful carboxyl,hydroxyl and quaternary ammonium cationic groups,and self-healing the micro-damages to ensure stable conduction pathways of the electrode.As a result,the Li-S batteries based on this novel multifunctional binder and simple commercial sulfur/carbon composites cathode exhibit excellent specific capacity and cycling stability.In particular,the specific capacity decay per cycle of the cell is only 0.064%along with high Coulombic efficiency after 550 cycles at 1.0 C,which is superior to most of the reported binders.Even under high sulfur loading,moreover,the cathode can deliver superior areal capacity and cycling stability.This proposed binder provides a new way for the design of high-stability sulfur cathodes.
基金This work was supported by the National Natural Science Foundation of China(Project No.U20A20260)the China Central Government Guide for the Development of Local Science and Technology Special Funds(226Z1202G)the Natural Science Foundation of Hebei Province(Grant Nos.B2020202042,B2020202073 and C20200320).
文摘The application of high-performance lithium-sulfur(Li-S)batteries is severely influenced by the“shuttle effect”of polysulfides and the volume change of sulfur cathode.Herein,two different polymeric binders SOT-A and SOT-C with three-dimensional network structure containing polar groups(sulfhydryl groups,amide groups and amino groups)are synthesized by the nucleophilic ring-opening polymerization(ROP)of thiolactone with amino groups.The network structure formed by hydrogen bonds and functional groups can resist the volume change of the cathode.The sulfhydryl groups and the S-S bond formed by oxidative dehydrogenation of sulfhydryl group participate in the charge and discharge process of the battery as active materials,which improves the discharge specific capacity of the battery.Polar functional groups have strong chemisorption on polysulfides and effectively inhibit the“shuttle effect”.The electrochemical performances of Li-S batteries containing SOT-A and SOT-C binders are significantly enhanced.At 1 C rate,the batteries achieve initial discharge specific capacity of 871 and 837 mAh·g^(-1),respectively,and have 83.9%and 62.5%capacity retention after 500 cycles.
基金financial support from the Australian Postgraduate Award,Australia Research Council Discovery Projects(DP160102627 and DP1701048343)Shenzhen Peacock Plan of China(KQTD2016112915051055)+1 种基金111 Project(D20015)of China Three Gorges University,National Natural Science Foundation of China(Grant No.51902036)the Natural Science Foundation of Chongqing Science&Technology Commission(Grant No.cstc2019jcyj-msxm1407).
文摘A mechanically strong binder with polar functional groups could overcome the dilemma of the large volume change during charge/discharge processes and poor cyclability of lithium-sulfur batteries(LSBs).In this work,for the first time,we report the use of poly(thiourea triethylene glycol)(PTTG)as a multifunctional binder for sulfur cathodes to enhance the performance of LSBs.As expected,the PTTG binder facilitates the high performance and stability delivered by the Sulfur-PTTG cathode,including a higher reversible capacity of 825 mAh g^(-1) at 0.2 C after 80 cycles,a lower capacity fading(0.123%per cycle)over 350 cycles at 0.5 C,a higher areal capacity of 2.5 mAh cm^(-2) at 0.25 mA cm^(-2),and better rate capability of 587 mAh g^(-1) at 2 C.Such superior electrochemical performances could be attributed to PTTG's strong chemical adsorption towards polysulfides which may avoid the lithium polysulfide shuttle effect and excellent mechanical characteristics which prevents electrode collapse during cycling and allows the Sulfur-PTTG electrode to maintain robust electron and ion migration pathways for accelerated redox reaction kinetics.
文摘In this study, we tried to develop the in situ coating methods of hydrophilic polymer solution containing water soluble dye on nonwoven sheet for the colorimetric film sensor. And color change of coated dye according to contact various gas samples (as strong acid and base, chloroform, ammonia and HF) of this dye-coated nonwoven film was examined for the application of chemically toxic materials detecting tools in the actual site of working place without aid of any kinds of detecting devices. By the addition of electron transfer agent (quinone derivatives), quick color change behaviors were observed within 10 seconds under the contact of various toxic gases in general condition(room temperature, 50% humidity).
文摘As phase separation between the small-molecule semiconductor and the polymer binder is the key enabler of blend-based organic field-effect transistors(OFETs)fabricated by low-cost solution processing,it is crucial to understand the underlying phase separation mechanisms that determine the phase morphology,which significantly impacts device performance.Beyond the parameter space investigated in previous work,here we investigate the formation of blends by varying the branch architecture of the polymer binder and by shortening the solvent dry time using ultrasonic spray casting.The phase morphologies of the resulting blend films have been thoroughly characterized with a variety of techniques in three dimensions over multiple length scales,including AFM,energy-filtered transmission electron microscope,and neutron reflectivity,and have been correlated with electrical transport performance.From the results,we have inferred that the phase morphology is kinetically determined,limited by the inherent slow movement of polymer macromolecules.The kinetic picture,supported by molecular dynamics modeling,not only consistently explains our observations but also resolves inconsistencies in previous works.The achieved mechanistic understanding will guide further optimization of blend-based organic electronics,such as OFETs and organic photovoltaics.
基金supported by the National Natural Science Foundation of China(52273081,52433002)the Young Talent Support Plan of Xi'an Jiaotong University。
文摘The significant volume expansion(over 300%)of silicon(Si)leads to rupture and erratic regeneration of the solid electrolyte interphase(SEI),resulting in parasitic reactions and capacity degradation.While polymer binders assist in the formation of stable SEI,the impact of binders on the electric double layer(EDL)structure and the mechanism underlying SEI formation at the molecular scale remains inadequately understood.In this study,we present a binder for Si anode that can modulate the initial adsorption properties and the solvent coordination behavior in EDL to achieve superior SEI.The strong affinity of the functional group for Li^(+)competes with the solvent to reduce the desolvation energy.This results in a redistribution of Li^(+)and the electrolyte solvent,decreasing free solvent content while inhibiting organic solvent reduction.The findings demonstrated that ultra-thin SEI(11 nm)consists of the inorganic inner layer and organic outer layer with high modulus and exceptional ionic conductivity,contributing to impressive capacity retention and exemplary rate performance.This work substantiates the role of binders in interfacial conditioning while providing novel insights into their practical application in silicon anode.
基金supported by the National Natural Science Foundation of China(U1804129,21771164,21671205 and U1804126)Zhongyuan Youth Talent Support Program of Henan ProvinceZhengzhou University Youth Innovation Program。
文摘High-capacity metal chalcogenides often suffer from low initial coulombic efficiency(ICE)and serious capacity fading owing to the shuttle effect and volumetric expansion.Various carbon-coating and fixing methods were used to improve the above-mentioned performance.However,the synthesis processes of them are complex and time-consuming,limiting their engineering applications.Herein,polar polymer binder sodium polyacrylate(PAANa)is selected as an example to solve the problems of metal chalcogenides(bare micro-sized FeS)without any modification of the active materials.The special function of the polymer binder in the interface between the active material particles and the electrolytes demonstrates that a PAANa-induced network structure on the surface of ion sulfide microparticles not only buffers the mechanical stress of particles during discharging-charging,but also participates in forming a ductile solid electrolyte interphase(SEI)with high interfacial ion transportation and enhanced ICE.The cyclic stability and rate performance can be simultaneously improved.This work not only provides a new understanding of the binder on electrode,but also introduces a new way to improve the performance of batteries.
基金financially supported by the National Key R&D Program of China(2019YFA0705703)Natural Science Foundation of Hubei Province(2021CFB082)+4 种基金Scientific Research Foundation of Wuhan Institute of Technology(K2021042)the Open Key Fund Project of State Key Laboratory of Advanced Technology for Materials Synthesis and Processing(Wuhan University of Technology,2022-KF-10)National Natural Science Foundation of China(22275142,U22B6011)China Postdoctoral Science Foundation(2021M703268)the Junior Fellow Program of Beijing National Laboratory for Molecular Sciences(2021BMS20062)。
文摘Lithium-sulfur(Li-S) batteries have shown promises for the next-generation, high-energy electrochemical storage, yet are hindered by rapid performance decay due to the polysulfide shuttle in the cathode and safety concerns about potential thermal runaway. To address the above challenges, herein, we show a flame-retardant cathode binder that simultaneously improves the electrochemical stability and safety of batteries. The combination of soft and hard segments in the polymer framework of binders allows high flexibility and mechanical strength for adapting to the drastic volume change during the Li(de)intercalation of the S cathode. The binder contains a large number of polar groups, which show the high affinity to polysulfides so that they help to anchor active S species at the cathode. These polar groups also help to regulate and facilitate the Li-ion transport, promoting the kinetics of polysulfide conversion reaction. The binder contains abundant phosphine oxide groups, which, in the case of battery's thermal runaway, decompose and release PO· radicals to quench the combustion reactions and stop the fire. Consequently, Li-S batteries using the new cathode binder show the improved electrochemical performance, including a low-capacity decay of 0.046% per cycle for 800 cycles at 1 C and favorable rate capabilities of up to 3 C. This work offers new insights on the practical realization of high-energy rechargeable batteries with stable storage electrochemistry and high safety.
