With excellent energy densities and highly safe performance,solidstate lithium batteries(SSLBs)have been hailed as promising energy storage devices.Solid-state electrolyte is the core component of SSLBs and plays an e...With excellent energy densities and highly safe performance,solidstate lithium batteries(SSLBs)have been hailed as promising energy storage devices.Solid-state electrolyte is the core component of SSLBs and plays an essential role in the safety and electrochemical performance of the cells.Composite polymer electrolytes(CPEs)are considered as one of the most promising candidates among all solid-state electrolytes due to their excellent comprehensive performance.In this review,we briefly introduce the components of CPEs,such as the polymer matrix and the species of fillers,as well as the integration of fillers in the polymers.In particular,we focus on the two major obstacles that affect the development of CPEs:the low ionic conductivity of the electrolyte and high interfacial impedance.We provide insight into the factors influencing ionic conductivity,in terms of macroscopic and microscopic aspects,including the aggregated structure of the polymer,ion migration rate and carrier concentration.In addition,we also discuss the electrode-electrolyte interface and summarize methods for improving this interface.It is expected that this review will provide feasible solutions for modifying CPEs through further understanding of the ion conduction mechanism in CPEs and for improving the compatibility of the electrode-electrolyte interface.展开更多
Substituting liquid electrolytes with solid elec-trolytes is considered as an important strategy to solve the problem of flammability and explosion for traditional lithium-ion batteries(LIB).However,neither inorganic ...Substituting liquid electrolytes with solid elec-trolytes is considered as an important strategy to solve the problem of flammability and explosion for traditional lithium-ion batteries(LIB).However,neither inorganic solid electrolytes(ISE)nor solid polymer electrolytes(SPE)alone can meet the operating requirements for room-temperature(RT)all-solid-state lithium metal batteries(ASSLMB).Here,we report a three-dimensional(3D)nanofiber framework reinforced polyethylene oxide(PEO)-based composite polymer electrolytes(CPE)through con-structing a nanofiber framework combining polyacryloni-trile(PAN)and fast Li-ion conductor Li_(0.33)La_(0.557)TiO_(3)(LLTO)framework by electrospinning method.Mean-while,the PEO electrolyte filled in the pores of the PAN/LLTO nanofiber framework can effectively isolate the direct contact between the chemically active Ti^(4+)in LLTO with lithium metal,thereby avoiding the occurrence of interfacial reactions.Enhanced electrochemical stability makes a wide electrochemical window up to 4.8 V with an ionic conductivity of about 9.87×10^(-5)S·cm^(-1)at RT.Benefiting from the excellent lithium dendrite growth inhibition ability of 3D PAN/LLTO nanofiber framework,especially when the mass of LLTO reaches twice that of the PAN,Li/Li symmetric cell could cycle stably for 1000 h without a short circuit.In addition,under 30℃,the LiFePO_(4)/Li ASSLMB using such CPE delivers large capacities of 156.2 and 140 mAh·g^(-1)at 0.2C and 0.5C,respectively.These results provide a new insight for the development of the next generation of safe,high-perfor-mance ASSLMBs.展开更多
Nano-La2O3 was modified with the vinyltrimethoxylsilane by hydrolysis and a novel poly （vinylidene fluoride-co-hexafluoropropylene） （PVDF-HFP） based composite polymer electrolyte doped with the modified nano-La2O3...Nano-La2O3 was modified with the vinyltrimethoxylsilane by hydrolysis and a novel poly （vinylidene fluoride-co-hexafluoropropylene） （PVDF-HFP） based composite polymer electrolyte doped with the modified nano-La2O3 was prepared by phase inversion method. The physicochemical properties were studied by SEM, FT-IR, XRD, TG and electrochemical methods. The results of FT-IR indicated that the nano-La2O3 was successfully modified with vinyltrimethoxylsilane. The XRD analysis showed that the incorporation of modified nano-La2O3 into the polymer electrolyte membranes could effectively reduce the crystallinity of PVDF-HFP, and the characterizations also suggested that thermal stability and electrochemical stability window could reach to 382°C and 5.1V, respectively; the reciprocal temperature dependence of ionic conductivity followed Vogel-Tamman-Fulcher （VTF） relation, ionic conductivity at room temperature was up to 3.5×10-3S/cm and lithium ions transference number was up to 0.42; the interfacial resistance increased at initial value about353Ω/cm2 and reached a steady value about 559Ω/cm2 after 5d storage at 30°C. The fabricated Li/As-prepared electrolytes/LiCoO2 coin cell showed excellent rate and cycle performances.展开更多
(PEO)8LiClO4-SiO2 composite polymer electrolytes(CPEs)were prepared by in-situ reaction,in which ethyl-orthosilicate(TEOS)was catalyzed by HCl and NH3.H2O,respectively.The ionic conductivity,the contact angle and the ...(PEO)8LiClO4-SiO2 composite polymer electrolytes(CPEs)were prepared by in-situ reaction,in which ethyl-orthosilicate(TEOS)was catalyzed by HCl and NH3.H2O,respectively.The ionic conductivity,the contact angle and the morphology of inorganic particles in the CPEs were investigated by AC impedance spectra,contact angle method and TEM.The conductivities of acid-catalyzed CPE and alkali-catalyzed CPE are 2.2×10-5and 1.1×10-5S/cm respectively at 30℃.The results imply that the catalyst plays an important role in the structure of in-situ preparation of SiO2,and influences the surface energy and conductivity of CPE films directly.Meanwhile,the ionic conductivity is related to the surface energy.展开更多
The lithiated covalent organic framework(named TpPa-SO_(3) Li),which was prepared by a mild chemical lithiation strategy,was introduced in poly(ethylene oxide)(PEO)to produce the composite polymer electrolytes(CPEs).L...The lithiated covalent organic framework(named TpPa-SO_(3) Li),which was prepared by a mild chemical lithiation strategy,was introduced in poly(ethylene oxide)(PEO)to produce the composite polymer electrolytes(CPEs).Li-ion can transfer along the PEO chain or across the layer of TpPa-SO_(3) Li within the nanochannels,resulting in a high Li-ion conductivity of3.01×10^(-4)S/cm at 60℃.When the CPE with 0.75 wt.%TpPa-SO_(3) Li was used in the LiFePO_(4)‖Li solid-state battery,the cell delivered a stable capacity of 125 mA·h/g after 250 cycles at 0.5 C,60℃.In comparison,the cell using the CPE without TpPa-SO_(3) Li exhibited a capacity of only 118 mA·h/g.展开更多
Low-cost and flexible solid polymer electrolytes are promising in all-solid-state Li-metal batteries with high energy density and safety.However,both the low room-temperature ionic conductivities and the small Li^(+)t...Low-cost and flexible solid polymer electrolytes are promising in all-solid-state Li-metal batteries with high energy density and safety.However,both the low room-temperature ionic conductivities and the small Li^(+)transference number of these electrolytes significantly increase the internal resistance and overpotential of the battery.Here,we introduce Gd-doped CeO_(2) nanowires with large surface area and rich surface oxygen vacancies to the polymer electrolyte to increase the interaction between Gd-doped CeO_(2) nanowires and polymer electrolytes,which promotes the Li-salt dissociation and increases the concentration of mobile Li ions in the composite polymer electrolytes.The optimized composite polymer electrolyte has a high Li-ion conductivity of 5×10^(-4)4 S cm^(-1) at 30℃ and a large Li+transference number of 0.47.Moreover,the composite polymer electrolytes have excellent compatibility with the metallic lithium anode and high-voltage LiNi_(0.8)Mn _(0.1)Co_(0.1)O_(2)(NMC)cathode,providing the stable cycling of all-solid-state batteries at high current densities.展开更多
PEO-LiClO4-TiO2 composite polymer electrolyte films were prepared. TiO2 was formed directly in matrix by hydrolysis and condensation reaction of tetrabutyl titanate. The crystallinity, morphology and ionic conductivit...PEO-LiClO4-TiO2 composite polymer electrolyte films were prepared. TiO2 was formed directly in matrix by hydrolysis and condensation reaction of tetrabutyl titanate. The crystallinity, morphology and ionic conductivity of composite polymer electrolyte films were examined by differential scanning calorimetry, scanning electron microscopy, atom force microscopy and alternating current impedance spectroscopy, respectively. The glass transition temperature and the crystallinity of composite polymer electrolytes are decreased compared with those of PEO-LiClO4 polymer electrolyte film. The results show that TiO2 particles are uniformly dispersed in PEO-LiClO4-5%TiO2 composite polymer electrolyte film. The maximal conductivity of 5.5×10、5 Scm at 20 ℃ of PEO-LiClO4-TiO2 film is obtained at 5% mass fraction of TiO2.展开更多
Poly（vinylidene fluoride-co-hexafluoropropylene） （PVDF-HFP） based composite polymer electrolyte （CPE） modified with CeO2, La2O3 and Y2O3 nano-rare earth oxides was prepared by phase inversion technique. Physical...Poly（vinylidene fluoride-co-hexafluoropropylene） （PVDF-HFP） based composite polymer electrolyte （CPE） modified with CeO2, La2O3 and Y2O3 nano-rare earth oxides was prepared by phase inversion technique. Physical and chemical properties of the modified CPEs were studied by SEM, TG-DSC and electrochemical methods. The results show that the CPE modified with 10% La2O3 （mass fraction） has the best practical applicability, which indicates that the thermal and electrochemical stability can reach over 400 ℃ and 4.5 V, respectively, and temperature dependence of ionic conductivity follows Vogel-Tamman-Fulcher （VTF） relationship and ionic conductivity at room temperature is up to 3.3 mS/cm. The interfacial resistance Ri reaches a stable value about 557 Ω after 6 d storage.展开更多
Satisfactory ionic conductivity,excellent mechanical stability,and high-temperature resistance are the prerequisites for the safe application of solid polymer electrolytes(SPEs)in all-solid-state lithium metal batteri...Satisfactory ionic conductivity,excellent mechanical stability,and high-temperature resistance are the prerequisites for the safe application of solid polymer electrolytes(SPEs)in all-solid-state lithium metal batteries(ASSLMBs).In this study,a novel poly(m-phenylene isophthalamide)(PMIA)-core/poly(ethylene oxide)(PEO)-shell nanofiber membrane and the functional Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)ceramic nanopar-ticle are simultaneously introduced into the PEO-based SPEs to prepare composite polymer electrolytes(CPEs).The core PMIA layer of composite nanofibers can greatly improve the mechanical strength and thermal stability of the CPEs,while the shell PEO layer can provide the 3D continuous transport channels for lithium ions.In addition,the introduction of functional LLZTO nanoparticle not only reduces the crys-tallinity of PEO,but also promotes the dissociation of lithium salts and releases more Li^(+)ions through its interaction with the Lewis acid-base of anions,thereby overall improving the transport of lithium ions.Consequently,the optimized CPEs present high ionic conductivity of 1.38×10^(−4)S/cm at 30℃,signifi-cantly improved mechanical strength(8.5 MPa),remarkable thermal stability(without obvious shrinkage at 150℃),and conspicuous Li dendrites blocking ability(>1800 h).The CPEs also both have good com-patibility and cyclic stability with LiFePO_(4)(>2000 cycles)and high-voltage LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NMC811)(>500 cycles)cathodes.In addition,even at low temperature(40℃),the assembled LiFePO4/CPEs/Li bat-tery still can cycle stably.The novel design can provide an effective way to exploit high-performance solid-state electrolytes.展开更多
A novel composite polymer electrolyte was prepared by blending an appropriateamount of LiClO_4 and 10 percent (mass fraction) fumed SiO_2 with the block copolymer of poly(ethylene oxide) (PEO) synthesized by poly (eth...A novel composite polymer electrolyte was prepared by blending an appropriateamount of LiClO_4 and 10 percent (mass fraction) fumed SiO_2 with the block copolymer of poly(ethylene oxide) (PEO) synthesized by poly (ethylene glycol) (PEG) 400 and CH_2C1_2 The ionicconductivity, electrochemical stability, interfacial characteristic and thermal behavior of thecomposite polymer electrolyte were studied by the measurements of AC impedance spectroscopy, linearsweep voltammetry and differential scanning calorimetry (DSC), respectively. The glass transitiontemperature acts as a function of salt concentration, which increases with the LiClO_4 content.Lewis acid-base model interaction mechanism was introduced to interpret the interactive relationbetween the filled fumed SiO_2 and the lithium salt in the composite polymer electrolyte. Over thesalt concentration range and the measured temperature, the maximum ionic conductivity of thecomposite polymer electrolyte (10^(-4.41) S/cm) appeared at EO/Li=25 (mole ratio) and 30 deg C, andthe beginning oxidative degradation potential versus Li beyond 5 V.展开更多
Technical breakthrough of composite polymer electrolyte(CPE)is one of the key factors that determines the commercial process of the current solid-state lithium battery.However,high interface impedance limits its elect...Technical breakthrough of composite polymer electrolyte(CPE)is one of the key factors that determines the commercial process of the current solid-state lithium battery.However,high interface impedance limits its electrochemical performances.It is crucial to optimize the design of multiphase interfaces among different components in CPE for regulating Li+transport.Herein,a multi-affinity self-assembled 12-crown-4-TFSI(12C4-TFSI)supramolecular nanolayer is introduced into poly(vinylidene difluoride)-Li_(6.75)La_(3)Zr_(1.75)Ta_(0.25)O_(12)(PVDF-LLZTO)CPE as interface modifier.As a result,enhanced Li+conductivity of 4.29×10^(-4)S·cm^(-1),Li+transfer number of 0.44,and stable electrochemical window voltage of 4.8 V vs.Li/Li+at 30℃ are obtained.The symmetric Li||Li cell exhibits an improved critical current density(CCD)of 1.2 mA·cm^(-2) and steady cycling at 0.2 mA·cm^(-2) for over 850 h without visible voltage fluctuation.The assembled LiǁLiFePO4 coin solid-state cell delivers a high initial discharge capacity of 172.9 mAh·g^(-1) at 0.1 C,rate capability(up to 5.0 C)and outstanding cycling stability with a capacity retention of 87.2% after over 750 cycles at 1.0 C.The associated LiǁLiFePO4 pouch cell presents an initial specific discharge capacity of 112.3 mAh·g−1 and successfully runs 30 cycles with a final capacity of 101.8 mAh·g^(-1).This work offers a facile strategy to optimize multiphase interfaces of PVDF-LLZTO CPE for stable solid-state lithium battery.展开更多
Poly(vinylidene fluoride)(PVDF)-based solid polymer electrolytes(SPEs)with“lithium salt in polymer”configurations typically exhibit poor lithium salt dissociation and mechanical strength.In this study,we proposed a ...Poly(vinylidene fluoride)(PVDF)-based solid polymer electrolytes(SPEs)with“lithium salt in polymer”configurations typically exhibit poor lithium salt dissociation and mechanical strength.In this study,we proposed a composite polymer electrolyte(CPE)for solid-state lithium-ion batteries(LIBs)as a novel approach to address the challenges.The CPE incorporates a high dielectric polymer poly(vinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene)(P(VDF-TrFE-CTFE))as the polymer matrix,and sodium super ionic conductor(NASICON)-type ceramic Li_(1.5)Al_(0.5)Ti_(1.5)(PO_(4))_(3)(LATP)as fillers.The optimized CPE demonstrates enhanced dissociation of lithium salts,leading to high ionic conductivity tLi+(1.1 mS·cm^(-1))and improved lithium transference numbers(=0.51).Meanwhile,the interaction between LATP inorganic filler and P(VDF-TrFE-CTFE)enhances the elasticity and tensile strength(1.09 MPa)of the CPE.The graphite|CPE|NCM811(NCM stands for lithium nickel manganese cobalt oxide.Chemical formula of NCM811 is“LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)”)cell achieves a high specific capacity of 160 mAh·g^(-1) with excellent cycles stably for 300 cycles at 1 C.In addition,the flexible graphite|CPE|NCM811 pouch cell demonstrates exceptional capacity stability under dynamic bending for 10,000 times.Furthermore,the CPE can fulfil the fabrication process needs of flexible stacking-type and winding-type cells,highlighting its versatility and suitability for various LIB configurations in real applications.展开更多
With the merits of both solid polymer electrolytes(SPEs)and inorganic ceramic electrolytes(ICEs),composite polymer electrolytes(CPEs)prepared by coupling polymer matrix with inorganicfillers are broadly utilized in so...With the merits of both solid polymer electrolytes(SPEs)and inorganic ceramic electrolytes(ICEs),composite polymer electrolytes(CPEs)prepared by coupling polymer matrix with inorganicfillers are broadly utilized in solid lithium metal batteries(SLMBs).However,CPEs fabricated by a singlefiller with polymer matrix often exhibit unsatisfactory performance.Here,prepared by coupling poly(ethylene oxide)(PEO)matrix with a natural additive carboxymethyl cellulose lithium(CMC-Li)and an inorganicfiller mineral hectorite(Ht),an efficient CPE is reported.Detailedly,CMC-Li is considered to act as a“bridge”,which connects the Ht nanosheets distributed in PEO,thus establishing continuous Li^(+)transmission channels.Ht with a nanolayers structure vividly acts as“bricks”,pave the way for ion transference.In addition,oxygen atoms in CMC-Li contribute to adequately dissociating lithium salts,hydrogen bonding generated by hydroxyl groups is propitious to anchor anions to increase the Liþtransference number.Under the synergistic effect brought by CMC-Li and Ht,the electrolyte membrane PEO-10%Ht-4%CMC-Li(PHCL,in mass fraction)displays a high Liþtransfer number(0.73)and exceptional Li^(+)conductivity at 25℃(2.5×10^(-4)S/cm).Our work demonstrates a powerful mean to fabricate the efficient electrolyte membrane for SLMBs.展开更多
High-performance lithium metal batteries benefit from the construction of composite polymer electrolytes(CPEs)which are synthesized by incorporating inorganic fillers into polymer matrices[1].However,the random distri...High-performance lithium metal batteries benefit from the construction of composite polymer electrolytes(CPEs)which are synthesized by incorporating inorganic fillers into polymer matrices[1].However,the random distribution of added fillers within the polymer matrix can lead to tortuous ion pathways and longer transmission distances(Fig.1).As a result,the ion transport capability of CPEs may decrease,while interface contact may deteriorate.Therefore,the organized arrangement of fillers emerges as a crucial consideration in constructing electrolyte membranes.One highly effective approach is the adoption of a vertically aligned filler configuration,where ceramic fillers are constructed to be perpendicular to the electrolyte membrane.If so,the filler/electrolyte interface impedance can be significantly reduced,while continuous ion transport channels along the specified direction are formed,thus significantly enhancing the ion conduction(Fig.1(a))[1].展开更多
Solid-state lithium batteries(SSLBs)have been identified as one kind of the most promising energy conversion and storage devices because of their safety,high energy density,and long cycling life.The development of sol...Solid-state lithium batteries(SSLBs)have been identified as one kind of the most promising energy conversion and storage devices because of their safety,high energy density,and long cycling life.The development of solid-state electrolyte is vital to commercialize SSLBs.Composite polymer electrolyte(CPE),derived by compositing inorganic particles into solid polymer electrolyte has become the most practical species for SSLBs because it inherits the advantages of polymer electrolyte and simultaneously achieves enhanced ionic conductivity and mechanical properties.The characteristics of inorganic particles and their interaction with polymers strongly impact the performance of CPE,improving its ionic conductivity,mechanical properties,thermal and electrochemical stability,as well as interface compatibility with both electrodes.In this review,the effects of particle characteristics including its species,size,proportion,morphology on the ionic conductivity and mechanical properties of CPE are reviewed.Meanwhile,some novel composite strategies are also introduced including surface modification,hybridization,and alignment of particles in polymer matrices,as well as some new preparation methods of CPE.The interactions between particles and other components in CPE including polymer matrices or lithium salt are particularly focused herein to reveal the lithium conductive mechanism.Finally,a perspective on the direction of future CPE development for SSLBs is presented.展开更多
The development of metallic lithium anode is restrained by lithium dendrite growth during cycling.The solid polymer electrolyte with high mechanical strength and lithium ion conductivity could be applied to inhibit li...The development of metallic lithium anode is restrained by lithium dendrite growth during cycling.The solid polymer electrolyte with high mechanical strength and lithium ion conductivity could be applied to inhibit lithium dendrite growth.To prepare the high-performance solid polymer electrolyte,the environment-friendly and cheap bacterial cellulose(BC)is used as filler incorporating with PEO-based electrolyte owing to good mechanical properties and Li salts compatibility.PEO/Li TFSI/BC composite solid polymer electrolytes(CSPE)are prepared easily by aqueous mixing in water.The lithium ion transference number of PEO/Li TFSI/BC CSPE is 0.57,which is higher than PEO/Li TFSI solid polymer electrolyte(SPE)(0.409).The PEO/Li TFSI/BC CSPE exhibits larger tensile strength(4.43 MPa)than PEO/Li TFSI SPE(1.34 MPa).The electrochemical window of composite electrolyte is widened 1.43 V by adding BC.Density functional theory calculations indicate that flex of PEO chains around Li atoms is suppressed,suggesting the enhanced lithium ion conductivity.Frontier molecular orbitals results suggest that an unfavorable intermolecular charge transfer lead to achieve higher potential for BC composite electrolyte.All solid-state Li metal battery with PEO/Li TFSI/BC CSPE delivers longer cycle life for 600 cycles than PEO/Li TFSI SPE battery(50 cycles).Li symmetrical battery using PEO/Li TFSI/BC CSPE could be stable for 1160 h.展开更多
The conductivities of polyethylene oxide (PEO)-based polymer electrolytes (PE) can be improved by the addition of inorganic inert powder. The composite polymer electrolytes (CPE) PEO10LiX (X=4ClO- or 322N(CFSO)-)-Li2T...The conductivities of polyethylene oxide (PEO)-based polymer electrolytes (PE) can be improved by the addition of inorganic inert powder. The composite polymer electrolytes (CPE) PEO10LiX (X=4ClO- or 322N(CFSO)-)-Li2TiO3 were prepared by solution casting with inorganic solid electrolyte Li2TiO3 powder as a filler. Results showed that the conductivities of PEO10LiClO4-3wt% Li2TiO3 and PEO10LiN(CF3SO2)2-10wt% Li2TiO3 at 30 ℃ were 8.6×10-6 and 5.6×10-5 S·cm-1, respectively. The conductivities of CPE increased with the decrease of filler抯 particle size. The ionic conduction mechanism analysis showed that there may be three conduction routes in the CPE, i.e., PEO bulk, polymer-filler interface and Li2TiO3 crystal.展开更多
Rational composite design is highly important for the development of high-performance composite polymer electrolytes(CPEs)for solid-state lithium(Li)metal batteries.In this work,Li closo-borohydride,Li_(2)B_(12)H_(12)...Rational composite design is highly important for the development of high-performance composite polymer electrolytes(CPEs)for solid-state lithium(Li)metal batteries.In this work,Li closo-borohydride,Li_(2)B_(12)H_(12),is introduced to poly(vinylidene fluoride)-Li-bis-(trifluoromethanesulfonyl)imide(PVDF-LiTFSI)with a bound N-methyl pyrrolidone plasticizer to form a novel CPE.This CPE shows superb Li^(+)conduction properties,as evidenced by its conductivity of 1.43×10^(-4) S cm^(-1) and Li^(+)transference number of 0.34 at 25℃.Density functional theory calculations reveal that Li_(2)B_(12)H_(12),which features electron-deficient multicenter bonds,can facilitate the dissociation of LiTFSI and enhance the immobilization of TFSI to improve the Li^(+)conduction properties of the CPE.Moreover,the fabricated CPE exhibits excellent electrochemical,thermal,and mechanical stability.The addition of Li_(2)B_(12)H_(12) can help form a protective layer at the anode/electrolyte interface,thereby preventing unwanted reactions.The above benefits of the fabricated CPE contribute to the high compatibility of the electrode.Symmetric Li cells can be stably cycled at 0.2mA cm^(-2) for over 1200 h,and Li||LiFePO_(4) cells can deliver a reversible specific capacity of 140mAh g^(-1) after 200 cycles at 1C at 25℃ with a capacity retention of 98%.展开更多
Solid electrolytes are the most promising candidate for replacing liquid electrolytes due to their safetyand chemical stability advantages. However, a single inorganic or organic solid electrolyte cannot meetthe requi...Solid electrolytes are the most promising candidate for replacing liquid electrolytes due to their safetyand chemical stability advantages. However, a single inorganic or organic solid electrolyte cannot meetthe requirements of commercial all-solid-state batteries (ASSBs), which motivates the composite polymerelectrolyte (CPE). Herein, a CPE of boron nitride nanofiber (BNNF) with a high specific surface area, richpore structure, and poly (ethylene oxide) (PEO) are reported. Anions strongly adsorb on the surface ofBNNF through electrostatic interactions based on oxygen vacancies, promoting the dissociation of lithiumsalts at the two-phase interface. The three-dimensional (3D) BNNF network provides three advantagesin the CPE, including (i) improving ionic conductivity through strong interaction between polymers andfillers, (ii) improving mechanical properties through weaving a robust skeleton, and (iii) improving stability through a rapid and uniform thermal dispersion pathway. Therefore, the CPE with BNNF delivers highionic conduction of 4.21 × 10^(−4) S cm^(−1) at 60 ℃ and excellent cycling stability (plating/stripping cyclesfor 2000 h with a low overpotential of ∼40 mV), which results in excellent electrochemical performanceof LiFePO_(4) (LFP) full cell assembled with CPE-5BNNF-1300 (152.7 mAh g^(−1) after 200 cycles at 0.5 C, and134.8 mAh g^(−1) at 2.0 C). Furthermore, when matched with high-voltage LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2) (NCM622), italso exhibits an outstanding rate capacity of 120.4 mAh g^(−1) at 1.0 C. This work provides insight into theBNNF composite electrolyte and promotes its practical application for ASSBs.展开更多
In comparison with lithium-ion batteries(LIBs)with liquid electrolytes,all-solid-state lithium batteries(ASSLBs)have been considered as promising systems for future energy storage due to their safety and high energy d...In comparison with lithium-ion batteries(LIBs)with liquid electrolytes,all-solid-state lithium batteries(ASSLBs)have been considered as promising systems for future energy storage due to their safety and high energy density.As the pivotal component used in ASSLBs,composite solid polymer electrolytes(CSPEs),derived from the incorporation of inorganic fillers into solid polymer electrolytes(SPEs),exhibit higher ionic conductivity,better mechanical strength,and superior thermal/electrochemical stability compared to the single-component SPEs,which can significantly promote the electrochemical performance of ASSLBs.Herein,the recent advances of CSPEs applied in ASSLBs are presented.The effects of the category,morphology and concentration of inorganic fillers on the ionic conductivity,mechanical strength,electrochemical window,interfacial stability and possible Li+transfer mechanism of CSPEs will be systematically discussed.Finally,the challenges and perspectives are proposed for the future development of high-performance CSPEs and ASSLBs.展开更多
基金the funding support from the National Key Research and Development Program of China(Grant Number 2021YFB2400300)National Natural Science Foundation of China(Grant Number 21875195,22021001)Fundamental Research Funds for the Central Universities(Grant Number 20720190040)。
文摘With excellent energy densities and highly safe performance,solidstate lithium batteries(SSLBs)have been hailed as promising energy storage devices.Solid-state electrolyte is the core component of SSLBs and plays an essential role in the safety and electrochemical performance of the cells.Composite polymer electrolytes(CPEs)are considered as one of the most promising candidates among all solid-state electrolytes due to their excellent comprehensive performance.In this review,we briefly introduce the components of CPEs,such as the polymer matrix and the species of fillers,as well as the integration of fillers in the polymers.In particular,we focus on the two major obstacles that affect the development of CPEs:the low ionic conductivity of the electrolyte and high interfacial impedance.We provide insight into the factors influencing ionic conductivity,in terms of macroscopic and microscopic aspects,including the aggregated structure of the polymer,ion migration rate and carrier concentration.In addition,we also discuss the electrode-electrolyte interface and summarize methods for improving this interface.It is expected that this review will provide feasible solutions for modifying CPEs through further understanding of the ion conduction mechanism in CPEs and for improving the compatibility of the electrode-electrolyte interface.
基金financially supported by Zhejiang Provincial Natural Science Foundation of China (No. LR20E020002)the National Natural Science Foundation of China (Nos.U20A20253 and 21972127)
文摘Substituting liquid electrolytes with solid elec-trolytes is considered as an important strategy to solve the problem of flammability and explosion for traditional lithium-ion batteries(LIB).However,neither inorganic solid electrolytes(ISE)nor solid polymer electrolytes(SPE)alone can meet the operating requirements for room-temperature(RT)all-solid-state lithium metal batteries(ASSLMB).Here,we report a three-dimensional(3D)nanofiber framework reinforced polyethylene oxide(PEO)-based composite polymer electrolytes(CPE)through con-structing a nanofiber framework combining polyacryloni-trile(PAN)and fast Li-ion conductor Li_(0.33)La_(0.557)TiO_(3)(LLTO)framework by electrospinning method.Mean-while,the PEO electrolyte filled in the pores of the PAN/LLTO nanofiber framework can effectively isolate the direct contact between the chemically active Ti^(4+)in LLTO with lithium metal,thereby avoiding the occurrence of interfacial reactions.Enhanced electrochemical stability makes a wide electrochemical window up to 4.8 V with an ionic conductivity of about 9.87×10^(-5)S·cm^(-1)at RT.Benefiting from the excellent lithium dendrite growth inhibition ability of 3D PAN/LLTO nanofiber framework,especially when the mass of LLTO reaches twice that of the PAN,Li/Li symmetric cell could cycle stably for 1000 h without a short circuit.In addition,under 30℃,the LiFePO_(4)/Li ASSLMB using such CPE delivers large capacities of 156.2 and 140 mAh·g^(-1)at 0.2C and 0.5C,respectively.These results provide a new insight for the development of the next generation of safe,high-perfor-mance ASSLMBs.
基金Project supported by Major Provincial Science and Technology Programs of Hunan (2011FJ1005)Central College on the 2010 Operational Costs of Basic Research Project (2010QZZD0101)
文摘Nano-La2O3 was modified with the vinyltrimethoxylsilane by hydrolysis and a novel poly （vinylidene fluoride-co-hexafluoropropylene） （PVDF-HFP） based composite polymer electrolyte doped with the modified nano-La2O3 was prepared by phase inversion method. The physicochemical properties were studied by SEM, FT-IR, XRD, TG and electrochemical methods. The results of FT-IR indicated that the nano-La2O3 was successfully modified with vinyltrimethoxylsilane. The XRD analysis showed that the incorporation of modified nano-La2O3 into the polymer electrolyte membranes could effectively reduce the crystallinity of PVDF-HFP, and the characterizations also suggested that thermal stability and electrochemical stability window could reach to 382°C and 5.1V, respectively; the reciprocal temperature dependence of ionic conductivity followed Vogel-Tamman-Fulcher （VTF） relation, ionic conductivity at room temperature was up to 3.5×10-3S/cm and lithium ions transference number was up to 0.42; the interfacial resistance increased at initial value about353Ω/cm2 and reached a steady value about 559Ω/cm2 after 5d storage at 30°C. The fabricated Li/As-prepared electrolytes/LiCoO2 coin cell showed excellent rate and cycle performances.
文摘(PEO)8LiClO4-SiO2 composite polymer electrolytes(CPEs)were prepared by in-situ reaction,in which ethyl-orthosilicate(TEOS)was catalyzed by HCl and NH3.H2O,respectively.The ionic conductivity,the contact angle and the morphology of inorganic particles in the CPEs were investigated by AC impedance spectra,contact angle method and TEM.The conductivities of acid-catalyzed CPE and alkali-catalyzed CPE are 2.2×10-5and 1.1×10-5S/cm respectively at 30℃.The results imply that the catalyst plays an important role in the structure of in-situ preparation of SiO2,and influences the surface energy and conductivity of CPE films directly.Meanwhile,the ionic conductivity is related to the surface energy.
基金supported by the State Key Laboratory of Catalytic Materials and Reaction Engineering(RIPP,SINOPEC)the National Natural Science Foundation of China(Nos.21878216,22005215)+1 种基金Hebei Province Innovation Ability Promotion Project(No.20312201D)the National Key Research and Development Program of China(No.2019YFE0118800)。
文摘The lithiated covalent organic framework(named TpPa-SO_(3) Li),which was prepared by a mild chemical lithiation strategy,was introduced in poly(ethylene oxide)(PEO)to produce the composite polymer electrolytes(CPEs).Li-ion can transfer along the PEO chain or across the layer of TpPa-SO_(3) Li within the nanochannels,resulting in a high Li-ion conductivity of3.01×10^(-4)S/cm at 60℃.When the CPE with 0.75 wt.%TpPa-SO_(3) Li was used in the LiFePO_(4)‖Li solid-state battery,the cell delivered a stable capacity of 125 mA·h/g after 250 cycles at 0.5 C,60℃.In comparison,the cell using the CPE without TpPa-SO_(3) Li exhibited a capacity of only 118 mA·h/g.
基金This work was supported by the National Natural Science Foundation of China (51973157,61904123)the Tianjin Natural Science Foundation (18JCQNJC02900)+3 种基金the Special Grade of the Financial Support from the China Postdoctoral Science Foundation (2020T130469)the Sci-ence and Technology Plans of Tianjin (19PTSYJC00010)the Science&Technol-ogy Development Fund of Tianjin Education Commission for Higher Education (2018KJ196)State Key Laboratory of Membrane and Membrane Separation,Tiangong University.
文摘Low-cost and flexible solid polymer electrolytes are promising in all-solid-state Li-metal batteries with high energy density and safety.However,both the low room-temperature ionic conductivities and the small Li^(+)transference number of these electrolytes significantly increase the internal resistance and overpotential of the battery.Here,we introduce Gd-doped CeO_(2) nanowires with large surface area and rich surface oxygen vacancies to the polymer electrolyte to increase the interaction between Gd-doped CeO_(2) nanowires and polymer electrolytes,which promotes the Li-salt dissociation and increases the concentration of mobile Li ions in the composite polymer electrolytes.The optimized composite polymer electrolyte has a high Li-ion conductivity of 5×10^(-4)4 S cm^(-1) at 30℃ and a large Li+transference number of 0.47.Moreover,the composite polymer electrolytes have excellent compatibility with the metallic lithium anode and high-voltage LiNi_(0.8)Mn _(0.1)Co_(0.1)O_(2)(NMC)cathode,providing the stable cycling of all-solid-state batteries at high current densities.
文摘PEO-LiClO4-TiO2 composite polymer electrolyte films were prepared. TiO2 was formed directly in matrix by hydrolysis and condensation reaction of tetrabutyl titanate. The crystallinity, morphology and ionic conductivity of composite polymer electrolyte films were examined by differential scanning calorimetry, scanning electron microscopy, atom force microscopy and alternating current impedance spectroscopy, respectively. The glass transition temperature and the crystallinity of composite polymer electrolytes are decreased compared with those of PEO-LiClO4 polymer electrolyte film. The results show that TiO2 particles are uniformly dispersed in PEO-LiClO4-5%TiO2 composite polymer electrolyte film. The maximal conductivity of 5.5×10、5 Scm at 20 ℃ of PEO-LiClO4-TiO2 film is obtained at 5% mass fraction of TiO2.
基金Project(2011FJ1005)supported by the Major Provincial Science and Technology Program of Hunan Province,ChinaProject(2010qzzd0101)supported by the Central College on the 2010 Operational Costs of Basic Research Program,China
文摘Poly（vinylidene fluoride-co-hexafluoropropylene） （PVDF-HFP） based composite polymer electrolyte （CPE） modified with CeO2, La2O3 and Y2O3 nano-rare earth oxides was prepared by phase inversion technique. Physical and chemical properties of the modified CPEs were studied by SEM, TG-DSC and electrochemical methods. The results show that the CPE modified with 10% La2O3 （mass fraction） has the best practical applicability, which indicates that the thermal and electrochemical stability can reach over 400 ℃ and 4.5 V, respectively, and temperature dependence of ionic conductivity follows Vogel-Tamman-Fulcher （VTF） relationship and ionic conductivity at room temperature is up to 3.3 mS/cm. The interfacial resistance Ri reaches a stable value about 557 Ω after 6 d storage.
基金supported by the National Natural Science Foundation of China (Nos.52203066,51973157,61904123)the Tianjin Natural Science Foundation (No.18JCQNJC02900)+3 种基金National Innovation and Entrepreneurship Training Program for College students (No.202310058007)Tianjin Municipal College Students’ Innovation and Entrepreneurship Training Program (No.202310058088)Science & Technology Development Fund of Tianjin Education Commission for Higher Education (No.2018KJ196)State Key Laboratory of Membrane and Membrane Separation,Tiangong University
文摘Satisfactory ionic conductivity,excellent mechanical stability,and high-temperature resistance are the prerequisites for the safe application of solid polymer electrolytes(SPEs)in all-solid-state lithium metal batteries(ASSLMBs).In this study,a novel poly(m-phenylene isophthalamide)(PMIA)-core/poly(ethylene oxide)(PEO)-shell nanofiber membrane and the functional Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)ceramic nanopar-ticle are simultaneously introduced into the PEO-based SPEs to prepare composite polymer electrolytes(CPEs).The core PMIA layer of composite nanofibers can greatly improve the mechanical strength and thermal stability of the CPEs,while the shell PEO layer can provide the 3D continuous transport channels for lithium ions.In addition,the introduction of functional LLZTO nanoparticle not only reduces the crys-tallinity of PEO,but also promotes the dissociation of lithium salts and releases more Li^(+)ions through its interaction with the Lewis acid-base of anions,thereby overall improving the transport of lithium ions.Consequently,the optimized CPEs present high ionic conductivity of 1.38×10^(−4)S/cm at 30℃,signifi-cantly improved mechanical strength(8.5 MPa),remarkable thermal stability(without obvious shrinkage at 150℃),and conspicuous Li dendrites blocking ability(>1800 h).The CPEs also both have good com-patibility and cyclic stability with LiFePO_(4)(>2000 cycles)and high-voltage LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NMC811)(>500 cycles)cathodes.In addition,even at low temperature(40℃),the assembled LiFePO4/CPEs/Li bat-tery still can cycle stably.The novel design can provide an effective way to exploit high-performance solid-state electrolytes.
文摘A novel composite polymer electrolyte was prepared by blending an appropriateamount of LiClO_4 and 10 percent (mass fraction) fumed SiO_2 with the block copolymer of poly(ethylene oxide) (PEO) synthesized by poly (ethylene glycol) (PEG) 400 and CH_2C1_2 The ionicconductivity, electrochemical stability, interfacial characteristic and thermal behavior of thecomposite polymer electrolyte were studied by the measurements of AC impedance spectroscopy, linearsweep voltammetry and differential scanning calorimetry (DSC), respectively. The glass transitiontemperature acts as a function of salt concentration, which increases with the LiClO_4 content.Lewis acid-base model interaction mechanism was introduced to interpret the interactive relationbetween the filled fumed SiO_2 and the lithium salt in the composite polymer electrolyte. Over thesalt concentration range and the measured temperature, the maximum ionic conductivity of thecomposite polymer electrolyte (10^(-4.41) S/cm) appeared at EO/Li=25 (mole ratio) and 30 deg C, andthe beginning oxidative degradation potential versus Li beyond 5 V.
基金We gratefully acknowledge the financial support of the National Key Research and Development Program of China(No.2021YFE0107200)the National Natural Science Foundation of China(No.21773167)the Key R&D Project funded by Department of Science and Technology of Jiangsu Province(No.BE2020003).
文摘Technical breakthrough of composite polymer electrolyte(CPE)is one of the key factors that determines the commercial process of the current solid-state lithium battery.However,high interface impedance limits its electrochemical performances.It is crucial to optimize the design of multiphase interfaces among different components in CPE for regulating Li+transport.Herein,a multi-affinity self-assembled 12-crown-4-TFSI(12C4-TFSI)supramolecular nanolayer is introduced into poly(vinylidene difluoride)-Li_(6.75)La_(3)Zr_(1.75)Ta_(0.25)O_(12)(PVDF-LLZTO)CPE as interface modifier.As a result,enhanced Li+conductivity of 4.29×10^(-4)S·cm^(-1),Li+transfer number of 0.44,and stable electrochemical window voltage of 4.8 V vs.Li/Li+at 30℃ are obtained.The symmetric Li||Li cell exhibits an improved critical current density(CCD)of 1.2 mA·cm^(-2) and steady cycling at 0.2 mA·cm^(-2) for over 850 h without visible voltage fluctuation.The assembled LiǁLiFePO4 coin solid-state cell delivers a high initial discharge capacity of 172.9 mAh·g^(-1) at 0.1 C,rate capability(up to 5.0 C)and outstanding cycling stability with a capacity retention of 87.2% after over 750 cycles at 1.0 C.The associated LiǁLiFePO4 pouch cell presents an initial specific discharge capacity of 112.3 mAh·g−1 and successfully runs 30 cycles with a final capacity of 101.8 mAh·g^(-1).This work offers a facile strategy to optimize multiphase interfaces of PVDF-LLZTO CPE for stable solid-state lithium battery.
文摘Poly(vinylidene fluoride)(PVDF)-based solid polymer electrolytes(SPEs)with“lithium salt in polymer”configurations typically exhibit poor lithium salt dissociation and mechanical strength.In this study,we proposed a composite polymer electrolyte(CPE)for solid-state lithium-ion batteries(LIBs)as a novel approach to address the challenges.The CPE incorporates a high dielectric polymer poly(vinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene)(P(VDF-TrFE-CTFE))as the polymer matrix,and sodium super ionic conductor(NASICON)-type ceramic Li_(1.5)Al_(0.5)Ti_(1.5)(PO_(4))_(3)(LATP)as fillers.The optimized CPE demonstrates enhanced dissociation of lithium salts,leading to high ionic conductivity tLi+(1.1 mS·cm^(-1))and improved lithium transference numbers(=0.51).Meanwhile,the interaction between LATP inorganic filler and P(VDF-TrFE-CTFE)enhances the elasticity and tensile strength(1.09 MPa)of the CPE.The graphite|CPE|NCM811(NCM stands for lithium nickel manganese cobalt oxide.Chemical formula of NCM811 is“LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)”)cell achieves a high specific capacity of 160 mAh·g^(-1) with excellent cycles stably for 300 cycles at 1 C.In addition,the flexible graphite|CPE|NCM811 pouch cell demonstrates exceptional capacity stability under dynamic bending for 10,000 times.Furthermore,the CPE can fulfil the fabrication process needs of flexible stacking-type and winding-type cells,highlighting its versatility and suitability for various LIB configurations in real applications.
基金the National Natural Science Foundation of China(22205147)Natural Science Foundation of Qinghai Province(2024-ZJ-952)Youth Innovation Promotion Association of the Chinese Academy of Sciences.
文摘With the merits of both solid polymer electrolytes(SPEs)and inorganic ceramic electrolytes(ICEs),composite polymer electrolytes(CPEs)prepared by coupling polymer matrix with inorganicfillers are broadly utilized in solid lithium metal batteries(SLMBs).However,CPEs fabricated by a singlefiller with polymer matrix often exhibit unsatisfactory performance.Here,prepared by coupling poly(ethylene oxide)(PEO)matrix with a natural additive carboxymethyl cellulose lithium(CMC-Li)and an inorganicfiller mineral hectorite(Ht),an efficient CPE is reported.Detailedly,CMC-Li is considered to act as a“bridge”,which connects the Ht nanosheets distributed in PEO,thus establishing continuous Li^(+)transmission channels.Ht with a nanolayers structure vividly acts as“bricks”,pave the way for ion transference.In addition,oxygen atoms in CMC-Li contribute to adequately dissociating lithium salts,hydrogen bonding generated by hydroxyl groups is propitious to anchor anions to increase the Liþtransference number.Under the synergistic effect brought by CMC-Li and Ht,the electrolyte membrane PEO-10%Ht-4%CMC-Li(PHCL,in mass fraction)displays a high Liþtransfer number(0.73)and exceptional Li^(+)conductivity at 25℃(2.5×10^(-4)S/cm).Our work demonstrates a powerful mean to fabricate the efficient electrolyte membrane for SLMBs.
基金supported by the National Natural Science Foundation of China(No.51972293)Hangzhou Key Research Program Project(2023SZD0099)LingYan Project(2024C01090).
文摘High-performance lithium metal batteries benefit from the construction of composite polymer electrolytes(CPEs)which are synthesized by incorporating inorganic fillers into polymer matrices[1].However,the random distribution of added fillers within the polymer matrix can lead to tortuous ion pathways and longer transmission distances(Fig.1).As a result,the ion transport capability of CPEs may decrease,while interface contact may deteriorate.Therefore,the organized arrangement of fillers emerges as a crucial consideration in constructing electrolyte membranes.One highly effective approach is the adoption of a vertically aligned filler configuration,where ceramic fillers are constructed to be perpendicular to the electrolyte membrane.If so,the filler/electrolyte interface impedance can be significantly reduced,while continuous ion transport channels along the specified direction are formed,thus significantly enhancing the ion conduction(Fig.1(a))[1].
基金This work was financially supported by the National Key R&D Program of China(Grant No.2018YFB0104300)the Beijing Municipal Natural Science Foundation(Grant No.2202027)the China Scholarship Council(No.202006460047).
文摘Solid-state lithium batteries(SSLBs)have been identified as one kind of the most promising energy conversion and storage devices because of their safety,high energy density,and long cycling life.The development of solid-state electrolyte is vital to commercialize SSLBs.Composite polymer electrolyte(CPE),derived by compositing inorganic particles into solid polymer electrolyte has become the most practical species for SSLBs because it inherits the advantages of polymer electrolyte and simultaneously achieves enhanced ionic conductivity and mechanical properties.The characteristics of inorganic particles and their interaction with polymers strongly impact the performance of CPE,improving its ionic conductivity,mechanical properties,thermal and electrochemical stability,as well as interface compatibility with both electrodes.In this review,the effects of particle characteristics including its species,size,proportion,morphology on the ionic conductivity and mechanical properties of CPE are reviewed.Meanwhile,some novel composite strategies are also introduced including surface modification,hybridization,and alignment of particles in polymer matrices,as well as some new preparation methods of CPE.The interactions between particles and other components in CPE including polymer matrices or lithium salt are particularly focused herein to reveal the lithium conductive mechanism.Finally,a perspective on the direction of future CPE development for SSLBs is presented.
基金supported partialy by the National Natural Science Foundation of China(No.51973171)Young Talent Support Plan of Xi’an Jiaotong University and Innovation Capability Support Program of Shaanxi(No.2018PT-28,2019PT-05)
文摘The development of metallic lithium anode is restrained by lithium dendrite growth during cycling.The solid polymer electrolyte with high mechanical strength and lithium ion conductivity could be applied to inhibit lithium dendrite growth.To prepare the high-performance solid polymer electrolyte,the environment-friendly and cheap bacterial cellulose(BC)is used as filler incorporating with PEO-based electrolyte owing to good mechanical properties and Li salts compatibility.PEO/Li TFSI/BC composite solid polymer electrolytes(CSPE)are prepared easily by aqueous mixing in water.The lithium ion transference number of PEO/Li TFSI/BC CSPE is 0.57,which is higher than PEO/Li TFSI solid polymer electrolyte(SPE)(0.409).The PEO/Li TFSI/BC CSPE exhibits larger tensile strength(4.43 MPa)than PEO/Li TFSI SPE(1.34 MPa).The electrochemical window of composite electrolyte is widened 1.43 V by adding BC.Density functional theory calculations indicate that flex of PEO chains around Li atoms is suppressed,suggesting the enhanced lithium ion conductivity.Frontier molecular orbitals results suggest that an unfavorable intermolecular charge transfer lead to achieve higher potential for BC composite electrolyte.All solid-state Li metal battery with PEO/Li TFSI/BC CSPE delivers longer cycle life for 600 cycles than PEO/Li TFSI SPE battery(50 cycles).Li symmetrical battery using PEO/Li TFSI/BC CSPE could be stable for 1160 h.
文摘The conductivities of polyethylene oxide (PEO)-based polymer electrolytes (PE) can be improved by the addition of inorganic inert powder. The composite polymer electrolytes (CPE) PEO10LiX (X=4ClO- or 322N(CFSO)-)-Li2TiO3 were prepared by solution casting with inorganic solid electrolyte Li2TiO3 powder as a filler. Results showed that the conductivities of PEO10LiClO4-3wt% Li2TiO3 and PEO10LiN(CF3SO2)2-10wt% Li2TiO3 at 30 ℃ were 8.6×10-6 and 5.6×10-5 S·cm-1, respectively. The conductivities of CPE increased with the decrease of filler抯 particle size. The ionic conduction mechanism analysis showed that there may be three conduction routes in the CPE, i.e., PEO bulk, polymer-filler interface and Li2TiO3 crystal.
基金supported by the National Natural Science Foundation of China(51971146 and 51971147)the Major Program for the Scientific Research Innovation Plan of Shanghai Education Commission(2019-01-07-00-07-E00015)+3 种基金Shanghai Outstanding Academic Leaders PlanGuangxi Key Laboratory of Information Materials(Guilin University of Electronic Technology,201017-K)Shanghai Rising-Star Program(20QA1407100)the General Program of Natural Science Foundation of Shanghai(20ZR1438400).
文摘Rational composite design is highly important for the development of high-performance composite polymer electrolytes(CPEs)for solid-state lithium(Li)metal batteries.In this work,Li closo-borohydride,Li_(2)B_(12)H_(12),is introduced to poly(vinylidene fluoride)-Li-bis-(trifluoromethanesulfonyl)imide(PVDF-LiTFSI)with a bound N-methyl pyrrolidone plasticizer to form a novel CPE.This CPE shows superb Li^(+)conduction properties,as evidenced by its conductivity of 1.43×10^(-4) S cm^(-1) and Li^(+)transference number of 0.34 at 25℃.Density functional theory calculations reveal that Li_(2)B_(12)H_(12),which features electron-deficient multicenter bonds,can facilitate the dissociation of LiTFSI and enhance the immobilization of TFSI to improve the Li^(+)conduction properties of the CPE.Moreover,the fabricated CPE exhibits excellent electrochemical,thermal,and mechanical stability.The addition of Li_(2)B_(12)H_(12) can help form a protective layer at the anode/electrolyte interface,thereby preventing unwanted reactions.The above benefits of the fabricated CPE contribute to the high compatibility of the electrode.Symmetric Li cells can be stably cycled at 0.2mA cm^(-2) for over 1200 h,and Li||LiFePO_(4) cells can deliver a reversible specific capacity of 140mAh g^(-1) after 200 cycles at 1C at 25℃ with a capacity retention of 98%.
基金financially supported by the Science and Tech-nology Innovation Base Project(No.226Z3606G)the National Natural Science Foundation of China(No.51802073)+3 种基金the Hebei Province Graduate Student Innovation Ability Training Project(No.CXZZBS2023040)the Hebei Province Eighth Batch of“100 People Plan”Project(No.E2018050008)the Natural Science Foundation of Hebei Province(No.E2018202129)Hebei Key Laboratory of Boron Nitride and Nano Materials.
文摘Solid electrolytes are the most promising candidate for replacing liquid electrolytes due to their safetyand chemical stability advantages. However, a single inorganic or organic solid electrolyte cannot meetthe requirements of commercial all-solid-state batteries (ASSBs), which motivates the composite polymerelectrolyte (CPE). Herein, a CPE of boron nitride nanofiber (BNNF) with a high specific surface area, richpore structure, and poly (ethylene oxide) (PEO) are reported. Anions strongly adsorb on the surface ofBNNF through electrostatic interactions based on oxygen vacancies, promoting the dissociation of lithiumsalts at the two-phase interface. The three-dimensional (3D) BNNF network provides three advantagesin the CPE, including (i) improving ionic conductivity through strong interaction between polymers andfillers, (ii) improving mechanical properties through weaving a robust skeleton, and (iii) improving stability through a rapid and uniform thermal dispersion pathway. Therefore, the CPE with BNNF delivers highionic conduction of 4.21 × 10^(−4) S cm^(−1) at 60 ℃ and excellent cycling stability (plating/stripping cyclesfor 2000 h with a low overpotential of ∼40 mV), which results in excellent electrochemical performanceof LiFePO_(4) (LFP) full cell assembled with CPE-5BNNF-1300 (152.7 mAh g^(−1) after 200 cycles at 0.5 C, and134.8 mAh g^(−1) at 2.0 C). Furthermore, when matched with high-voltage LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2) (NCM622), italso exhibits an outstanding rate capacity of 120.4 mAh g^(−1) at 1.0 C. This work provides insight into theBNNF composite electrolyte and promotes its practical application for ASSBs.
基金supported by the Innovative and Entrepreneurial Talent Plan(Jiangsu Province,China)。
文摘In comparison with lithium-ion batteries(LIBs)with liquid electrolytes,all-solid-state lithium batteries(ASSLBs)have been considered as promising systems for future energy storage due to their safety and high energy density.As the pivotal component used in ASSLBs,composite solid polymer electrolytes(CSPEs),derived from the incorporation of inorganic fillers into solid polymer electrolytes(SPEs),exhibit higher ionic conductivity,better mechanical strength,and superior thermal/electrochemical stability compared to the single-component SPEs,which can significantly promote the electrochemical performance of ASSLBs.Herein,the recent advances of CSPEs applied in ASSLBs are presented.The effects of the category,morphology and concentration of inorganic fillers on the ionic conductivity,mechanical strength,electrochemical window,interfacial stability and possible Li+transfer mechanism of CSPEs will be systematically discussed.Finally,the challenges and perspectives are proposed for the future development of high-performance CSPEs and ASSLBs.
