Slurry-like hybrid electrolyte with high lithium-ion transference number for dendrite-free lithium metal anode

Lithium metal anode is regarded as the ultimate choice for next-generation energy storage systems,due to the lowest negative electrochemical potential and super high theoretical specific capacity.However,the growth of lithium dendrite during the cycling process is still one of the most critical bottlenecks for its application.In this work,a slurry-like hybrid electrolyte is proposed towards the application for lithium metal anode,which is composed of a liquid electrolyte part and a nanometric silane-Al2O3 particle part.The hybrid electrolyte shows high ionic conductivity(3.89×10-3 S cm-1 at 25℃)and lithium-ion transference number(0.88).Especially,the resistance of hybrid electrolyte decreases compared to that of liquid electrolyte,while the viscosity of hybrid electrolyte increases.It is demonstrated that the hybrid electrolyte can effectively suppress the growth of lithium dendrite.Stable cycling of Li/Li cells at a current density up to 1 mA cm-2 is possible.The hybrid electrolyte helps to uniform the lithium ion flux inside the battery and partly comes from the formation of a rigid and highly conductive hybrid interfacial layer on the surface of lithium metal.This work not only provides a fresh way to stabilize lithium metal anode but also sheds light on further research for electrolyte optimization and design of lithium metal battery system.

The Transference Number

The performance of rechargeable batteries and other electrochemical systems depends on the rate at which the working ion(often a cation)is transported from one electrode to the other.The cation transference number is an important transport parameter that affects this rate.The purpose of this perspective is to distinguish between approximate and rigorous methods used in the literature to measure the transference number.We emphasize the fact that this parameter is dependent on the reference frame used in the analysis;care must be taken when comparing values obtained from different sources to account for differences in reference frames.We present data obtained from a well-characterized electrolyte.We compare rigorously determined transference numbers in two reference frames with values obtained by an approximate method.We conclude with a qualitative discussion of the relationship between the transference number and salt concentration gradients that are obtained when current is drawn through a battery。

A highly ionic transference number eutectogel hybrid electrolytes based on spontaneous coupling inhibitor for solid-state lithium metal batteries

Polymer-based solid electrolytes have been extensively studied for solid-state lithium metal batteries to achieve high energy density and reliable security.But,its practical application is severely limited by low ionic conductivity and slow Li+transference.Herein,based on the“binary electrolytes”of poly(vinylidene fluoride-chlorotrifluoroethylene)(P(VDF-CTFE))and lithium salt(LiTFSI),a kind of eutectogel hybrid electrolytes(EHEs)with high Li+transference number was developed via tuning the spontaneous coupling of charge and vacated space generated by Li-cation diffusion utilizing the Li6.4La3Zr1.4Ta0.6O12(LLZTO)dopant.LLZTO doping promotes the dissociation of lithium salt,increases Li+carrier density,and boosts ion jumping and the coordination/decoupling reactions of Li+.As a result,the optimized EHEs-10%possess a high Li-transference number of 0.86 and a high Li+conductivity of 3.2×10–4 S·cm–1 at room temperature.Moreover,the prepared EHEs-10%composite solid electrolyte presents excellent lithiumphilic and compatibility,and can be tested stably for 1,200 h at 0.3 mA·cm–2 with assembled lithium symmetric batteries.Likewise,the EHEs-10%films match well with high-loading LiFePO4 and LiCoO2 cathodes(>10 mg·cm–2)and exhibit remarkable interface stability.Particularly,the LiFePO4//EHEs-10%//Li and LiCoO2//EHEs-10%//Li cells deliver high rate performance of 118 mAh·g–1 at 1 C and 93.7 mAh·g–1 at 2 C with coulombic efficiency of 99.3%and 98.1%,respectively.This work provides an in-depth understanding and new insights into our design for polymer electrolytes with fast Li+diffusion.

Strategies to enhance Li^(+) transference number in liquid electrolytes for better lithium batteries

Growing market demand from portable electronics to electric automobiles boosts the development of lithium-ion batteries(LIBs)with high energy density and rate performance.However,strong solvation effect between lithium ions(Li^(+))and solvent molecules in common electrolytes limits the mobility of Li^(+)ions in electrolytes.Consequently,anions dominate the charge conduction in electrolytes,and in most cases,the value of Li^(+)transference number(T_(+))is between 0.2 and 0.4.A low T_(+)will aggravate concentration polarization in the process of charging and discharging,especially at high rate,which not only increases the overpotential but also intensifies side reactions,along with uneven deposition of lithium(Li)and the growth of lithium dendrites when lithium metal is used as anode.In this review,promising strategies to improve T_(+)in liquid electrolytes would be summarized.The migration of Li^(+)ions is affected directly by the types and concentration of lithium salts,solvents,and additives in bulk electrolytes.Besides,Li^(+)ions will pass through the separator and solid electrolyte interphase(SEI)when transferring between anodes and cathodes.With this in mind,we will classify and summarize threads of enhancing T_(+)from five aspects:lithium salts,solvents,additives,separators,and SEI based on different mechanisms,including covalently bonding,desolvation effect,Lewis acid-base interaction,electrostatic interaction,pore sieving,and supramolecular interaction.We believe this review will present a systematic understanding and summary on T_(+)and point out some feasible threads to enhance battery performance by enhancing T_(+).

Hydrogen-bonded organic framework modified separator for simultaneously enhancing the safety and electrochemical performance of Ni-rich lithium-ion battery

Nickel-rich layered oxide cathode(LiNi_(x)Co_(y)Mn_(1−x−y)O_(2),x>0.5,NCM)shows substantial potential for applications in longer-range electrical vehicles.However,the rapid capacity decay and serious safety concerns impede its practical viability.This work provides a hydrogen-bonded organic framework(HOF)modification strategy to simultaneously improve the electrochemical performance,thermal stability and incombustibility of separator.Melamine cyanurate(MCA),as a low-cost and reliable flame-retardant HOF,was implemented in the separator modification layer,which can prevent the battery short circuit even at a high temperature.In addition,the supermolecule properties of MCA provide unique physical and chemical microenvironment for regulating ion-transport behavior in electrolyte.The MCA coating layer enabled the nickel-rich layered oxide cathode with a high-capacity retention of 90.3%after 300 cycles at 1.0 C.Collectively,the usage of MCA in lithium-ion batteries(LIBs)affords a simple,low-cost and efficient strategy to improve the security and service life of nickel-rich layered cathodes.

Synergetic Control of Li^(+)Transport Ability and Solid Electrolyte Interphase by Boron-Rich Hexagonal Skeleton Structured All-Solid-State Polymer Electrolyte

High Li^(+)transference number electrolytes have long been understood to provide attractive candidates for realizing uniform deposition of Li^(+).However,such electrolytes with immobilized anions would result in incomplete solid electrolyte interphase(SEI)formation on the Li anode because it suffers from the absence of appropriate inorganic components entirely derived from anions decomposition.Herein,a boron-rich hexagonal polymer structured all-solid-state polymer electrolyte(BSPE+10%LiBOB)with regulated intermolecular interaction is proposed to trade off a high Li^(+)transference number against stable SEI properties.The Li^(+)transference number of the as-prepared electrolyte is increased from 0.23 to 0.83 owing to the boron-rich cross-linker(BC)addition.More intriguingly,for the first time,the experiments combined with theoretical calculation results reveal that BOB^(-)anions have stronger interaction with B atoms in polymer chain than TFSI^(-),which significantly induce the TFSI^(-)decomposition and consequently increase the amount of LiF and Li3N in the SEI layer.Eventually,a LiFePO_(4)|BSPE+10%LiBOBlLi cell retains 96.7%after 400 cycles while the cell without BC-resisted electrolyte only retains 40.8%.BSPE+10%LiBOB also facilitates stable electrochemical cycling of solid-state Li-S cells.This study blazes a new trail in controlling the Li^(+)transport ability and SEI properties,synergistically.

Understanding Lithium-ion Transport in Sulfolane- and Tetraglyme-Based Electrolytes Using Very Low-Frequency Impedance Spectroscopy

With the increasing interest in highly concentrated electrolyte systems,correct determination of the cation transference number is important.Pulsed-field gradient NMR technique,which measures self-diffusion coefficients,is often applied on liquid electrolytes because of the wide accessibility and simple sample preparation.However,since the assumptions of this technique,that is,complete salt dissociation,all ions participating in motion,and all of them moving independently,no longer hold true in concentrated solutions,the transference numbers,thus obtained are often over-estimated.In the present work,impedance spectroscopy at a frequency range of 1 MHz to 0.1 mHz was used to examine the concentration effect on lithium-ion transference number under anion-blocking conditions T abc Liþfor two electrolytes:lithium bis(fluorosulfonyl)imide(LiFSI)in sulfolane(SL)and lithium bis(trifluorosulfonyl)imide(LiTFSI)in tetraglyme(G4).The T abc Liþof the former was almost an order of magnitude higher than that of the latter.It also appeared to increase with increasing concentration while the latter followed an opposite trend.The faster Li^(+)transport in the SL system is attributed to the formation of a liquid structure consisting of extended chains/bridges of SL molecules and the anions,which facilitate a cation-hopping/ligand-exchanged-typed diffusion mechanism by partially decoupling the cations from the anions and solvent molecules.The G4 system,in contrast,is dominated by the formation of long-lived,stable[Li(G4)]+solvation cages that results in a sluggish Li+transport.The difference between the two transport mechanisms is discussed via comparison of the bulk ionic conductivity,viscosity,ion self-diffusion coefficients,and the Onsager transport coefficients.

Effect of junction potential on the EMF of bielectrolyte solid-state sensors

The EMF (electromotive force) expressions of bielectrolyte solid-state sensors derived from classical thermodynamics are not rigorous. They are only applicable in some special situations. In order to expand their applicable scope, they should be derived from irreversible thermodynamics theory. There is a junction potential term in the EMF equations of double solid electrolyte sensors derived from irreversible thermodynamics. The junction potential involves the ion transference numbers and the electron transference numbers of two kinds of solid electrolytes. When the transference numbers of reaction ions in the two solid electrolytes equal 1 only, the junction potential term is zero and two types of EMF equations become the same.

Determination of Mass Transfer Parameters During Deep Fat Frying of Rice Crackers

The accuracy of the knowledge of mass transfer parameters （effective moisture diffusivity, mass transfer Biot number and mass transfer coefficient） in the case of frying food, is essential and important for designing, modeling and process optimization. This study is undertaken to develop an approach for determining mass transfer parameters during frying of spherical rice cracker in sunflower oil at 150, 170 and 190 ℃. These parameters were evaluated from the plots of dimensionless concentration ratios against time of frying. Effective moisture diffusivity, mass transfer Biot number and mass transfer coefficient ranged between 1.24×10^-8 to 2.36×10^-8 m^2/s, 1.96 to 2.34 and 5.51×10^-6 to 9.70×10^-6 m/s, respectively. Effective moisture diffusivity and mass transfer coefficient were found to increase with an increasing frying temperature, whereas mass transfer Biot number decreased. An Arrhenius-type relationship was found between effective diffusivity coefficient and frying temperature.

Experimental and CFD Heat Transfer Studies of Al2Oa-Water Nanofluid in a Coiled Agitated Vessel Equipped with Propeller

This paper presents the heat transfer characteristics of A1203-water nanofluid in a coiled agitated vessel with propeller agitator. The experimental study was conducted using 0.10%, 0.20% and 0.30% volume concentra tion of A1203-water nanofluids. The results showed considerable enhancement of convective heat transfer using the nanofluids. The empirical correlations developed for Nusselt number in terms of Reynolds number, Prandtl number, viscosity ratio and volume concentration fit with the experimental data within ±10%. The heat transfer characteris tics were also simulated using computational fluid dynamics using FLUENT software with the standard ke model and multiple reference frame were adopted. The computational fluid dynamics （CFD） predicted Nusselt number agrees well with the experimental value and the discrepancy is found to be less than ＋8%.

Numerical analysis of heat transfer intensity from twin slot vertical jet impingement on strip surface after hot rolling

The flow field and heat transfer of the strip surface due to the twin slot vertical jet impingement were investigated using the ANSYS FLUENT.The RNG k-ε model was carried out in the turbulent calculation.Systematic parametric research was conducted by varying the jet velocity of nozzle exit(V=5 m/s,7.5 m/s,10 m/s),the temperature of cooling water(T_w=280 K,300 K),the normalized spacing from the nozzle to the strip surface(H=10,15,20,33),and the normalized spacing from the nozzle to nozzle centerline(W=0,15,30).The velocity streamline of the flow domain and the general trend of the distribution of the local Nusselt number on the impingement surface of strip were obtained.The result indicate that,the average Nusselt number increases by about70%(90%) as the jet velocity is increased from 5 m/s to 7.5 m/s(from 7.5 m/s to 10 m/s),and T_w,Hand//have minimal effect on it.While the valley Nusselt number decreases by about 10%-43%with the increase of H and W.The functional relationship between the average Nusselt number and the systematic parameters is derived by the least square regression method.

Lamellar quasi-solid electrolyte with nanoconfined deep eutectic solvent for high-performance lithium battery

Electrolytes with high-efficiency lithium-ion transfer and reliable safety are of great importance for lithium battery.Although having superior ionic conductivity(10^(−3)–10^(−2) S·cm^(−1)),traditional liquid-state electrolytes always suffer from low lithium-ion transference number(tLi+<0.4)and thus undesirable battery performances.Herein,the deep eutectic solvent(DES)is vacuum-filtered into the~1 nm interlayer channel of vermiculite(Vr)lamellar framework to fabricate a quasi-solid electrolyte(Vr-DES QSE).We demonstrate that the nanoconfinement effect of interlayer channel could facilitate the opening of solvation shell around lithiumion.Meanwhile,the interaction from channel wall could inhibit the movement of anion.These enable high-efficiency lithium-ion transfer:2.61×10^(−4)S·cm^(−1)at 25℃.Importantly,the tLi+value reaches 0.63,which is 4.5 times of that of bulk DES,and much higher than most present liquid/quasi-solid electrolytes.In addition,Vr-DES QSE shows significantly improved interfacial stability with Li anode as compared with DES.The assembled Li symmetric cell can operate stably for 1000 h at 0.1 mA·cm^(−2).The lithium iron phosphate(LFP)|Vr-DES QSE|Li cell exhibits high capacity of 142.1 mAh·g^(−1)after 200 cycles at 25℃ and 0.5 C,with a capacity retention of 94.5%.The strategy of open solvation shell through nanoconfinement effect of lamellar framework may shed light on the development of advanced electrolytes.

Formatted PVDF in lamellar composite solid electrolyte for solidstate lithium metal battery

Solid polymer electrolytes(SPEs)hold great application potential for solid-state lithium metal battery because of the excellent interfacial contact and processibility,but being hampered by the poor room-temperature conductivity(~10^(−7)S·cm^(−1))and low lithium-ion transference number(tLi+).Here,a lamellar composite solid electrolyte(Vr-NH_(2)@polyvinylidene fluoride(PVDF)LCSE)withβ-conformation PVDF is fabricated by confining PVDF in the interlayer channel of-NH_(2)modified vermiculite lamellar framework.We demonstrate that the conformation of PVDF can be manipulated by the nanoconfinement effect and the interaction from channel wall.The presence of-NH_(2)groups could induce the formation ofβ-conformation PVDF through electrostatic interaction,which serves as continuous and rapid lithium-ion transfer pathway.As a result,a high room-temperature ionic conductivity of 1.77×10^(−4)S·cm^(−1)is achieved,1-2 orders of magnitude higher than most SPEs.Furthermore,Vr-NH_(2)@PVDF LCSE shows a high tLi+of 0.68 because of the high dielectric constant,~3 times of that of PVDF SPE,and surpassing most of reported SPEs.The LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)||Li cell assembled by Vr-NH_(2)@PVDF LCSE obtains a discharge specific capacity of 137.1 mAh·g^(−1)after 150 cycles with a capacity retention rate of 93%at 1 C and 25℃.This study may pave a new avenue for high-performance SPEs.

High-stability double-layer polymer-inorganic composite electrolyte fabricated through ultraviolet curing process for solid-state lithium metal batteries

Electrolyte interface resistance and low ionic conductivity are essential issues for commercializing solid-state lithium metal batteries(SSLMBs).This work details the fabrication of a double-layer solid composite electrolyte(DLSCE)for SSLMBs.The composite comprises poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)and poly(methyl methacrylate)(PMMA)combined with 10 wt.%of Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO),synthesized through an ultraviolet curing process.The ionic conductivity of the DLSCE(2.6×10^(-4) S·cm^(-1))at room temperature is the high lithium-ion transference number(0.57),and the tensile strength is 17.8 MPa.When this DLSCE was assembled,the resulted LFP/DLSCE/Li battery exhibited excellent rate performance,with the discharge specific capacities of 162.4,146.9,93.6,and 64.0 mA·h·g^(-1) at 0.1,0.2,0.5,and 1 C,respectively.Furthermore,the DLScE demonstrates remarkable stability with lithium metal batteries,facilitating the stable operation of a Li/Li symmetric battery for over 200 h at both 0.1 and 0.2 mA-cm^(-2).Notably,the formation of lithium dendrites is also effectively inhibited during cycling.This work provides a novel design strategy and preparation method for solid composite electrolytes.

Novel single-ion conducting polymer electrolytes with high toughness and high resistance against lithium dendrites

Solid-state polymer electrolytes are considered as an alternative to classic liquid electrolytes,particularly for application in highenergy lithium metal batteries.With respect to common dual-ion conductors,single-ion conducting polymer electrolytes(SICPEs)are less affected by lithium dendrites growth and thus are particularly interesting for application in lithium metal batteries.In this work,novel SIC-PEs are developed,based on an ionomer having poly(ethylene-alt-maleimide)backbone and lithium phenylsulfonyl(trifluoromethanesulfonyl)imide pendant moieties,further blended with poly(ethylene oxide)(PEO)and poly(ethylene glycol)dimethyl ether(PEGDME).These SIC-PEs exhibit ionic conductivity around~7×10^(−6)S·cm^(−1) at 70℃,lithium transference number close to unity,and excellent mechanical properties,with fracture toughness over 30 J·cm^(−3).Additionally,the electrolytes show very high resistance against lithium dendrites growth,by cycling for more than 1200 h in Li°symmetric cells at a current density of 0.1 mA·cm^(−2).LiFePO4||Li°cells with these SIC-PEs were cycled at 70℃ and C/10,showing initial capacity of almost 160 mAh·g^(−1)and residual capacity of 45%after 100 cycles.This work shows that single-ion conducting polymer electrolytes based on poly(ethylene-alt-maleimide)backbone are promising materials for application as electrolytes or catholytes in lithium metal polymer batteries.

两性分子掺杂自支撑单离子传导聚合物电解质及其锂金属二次电池

制备高离子电导率的自支撑单离子传导聚合物电解质仍然面临挑战.本文中,我们通过聚[4,4’(二苯醚基)-5,5’-联苯并咪唑]侧链化学接枝丙烷磺酰(三氟甲基磺酰)亚胺锂,得到自支撑聚合物电解质(PBIg-LiPSI).PBI-g-LiPSI具有优异的成膜性能,实验发现,掺杂两性分子1-甲基-3-丙烷磺酰(三氟甲基磺酰)亚胺咪唑内盐(MeImPSI)后,离子电导率和^(7)Li核磁共振峰的化学位移都随着掺杂两性分子的质量分数呈线性递增.PBI-g-LiPSI/MeImPSI(25 wt%)凝胶自支撑单离子传导聚合物电解质的室温离子电导率是0.68 mS cm^(-1),锂离子迁移数是0.95.使用该电解质隔膜的金属锂对称电池在±0.5 mA cm^(-2)@2 mA h cm^(-2)运行2100小时未发生短路,金属锂二次电池可在1C下稳定循环500圈.本工作开发了一种用于金属锂二次电池的两性分子掺杂自支撑单离子传导聚合物电解质.

An ion-percolating electrolyte membrane for ultrahigh efficient and dendrite-free lithium metal batteries

The development of lithium(Li)metal batteries has been severely limited by the formation of lithium dendrites and the associated catastrophic failure and inferior Coulombic efficiency which caused by non-uniform or insufficient Li^(+)supply across the electrode-electrolyte interface.Therefore,a rational strategy is to construct a robust electrolyte that can allow efficient and uniform Li^(+)transport to ensure sufficient Li^(+)supply and homogenize the Li plating/stripping.Herein,we report an ion-percolating electrolyte membrane that acts as a stable Li^(+)reservoir to ensure a near-single Li^(+)transference number(0.78)and homogenizes Li^(+)migration to eradicate dendrite growth,endowing Li//LFP cell with an ultrahigh average Coulombic efficiency(ca.99.97%)after cycling for nearly half of a year and superior cycling stability when pairing with LiCoO_(2) with limited Li amount and LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2).These estimable attributes demonstrate significant potential of utility value for the ion-percolating electrolyte.

Physical Characterization of Ionic Liquid-Modified Polyvinyl Alcohol and Sodium Thiocyanate Polymer Electrolytes for Electrochemical Double-Layer Capacitor Application

Novel gel polymer electrolytes(GPEs)composed of polyvinyl alcohol(PVA)and sodium thiocyanate were developed via a solution casting technique.An ionic liquid(IL),1-ethyl-3-methyl-imidazolium tricyanomethanide([EMIM][TCM]),was doped into a polymer–salt complex system(PVA+NaSCN)to further enhance the conductivity.IL-doped polymer electrolyte(ILDPE)films were characterized using X-ray diffraction(XRD),polarized optical microscopy(POM),Fourier-transform infrared(FTIR)spectroscopy,and conductivity measurements.XRD was performed to check the degree of crystallinity and amorphicity of the ILDPE films,and the amorphicity of GPEs increased with the increase of the IL content.POM was employed to evaluate the changes in the surface morphology due to the inclusion of salt and IL in the PVA.The compositional nature of the GPE films was examined via FTIR studies.The electrical and electrochemical properties were characterized by cyclic voltammetry and electrochemical impedance spectroscopy.The maximum conductivity for the GPE film was estimated to be 1.10×10^(-5) S/cm for 6%(mass fraction)of IL in the polymer–salt complex.The ionic transference number was approximately 0.97.An electrochemical double-layer capacitor(EDLC)was built from optimized GPE films and reduced graphene oxide-based electrodes.The specific capacitance calculated from the cyclic voltammograms of the EDLC cells was 3 F/g.

An ultra-low concentration electrolyte with fluorine-free bulky anions for stable potassium metal batteries

Potassium metal battery is a promising alternative to Li-ion battery for large-scale energy storage due to the abundant potassium resources and high energy density.However,it suffers from rapid capacity fading and safety issues due to the uncontrolled dendrite growth.Herein,we design a fluorine-free ultra-low concentration electrolyte(ULCE)with the super bulky[BPh_(4)]^(−) anions for stable potassium metal battery.In this special electrolyte,the migration rate of K+in the electrolyte is about six times faster than that of the[BPh_(4)]^(−) anions because of the super bulky structure of the[BPh_(4)]^(−) anions,thus resulting in a high K^(+)transference number of 0.76.This high transference number can effectively make up for the deficiency of K^(+)in ULCE for ensuring the normal operation of the potassium metal battery.In addition,the improved transference number can also promote the uniform distribution of K^(+)flux on the surface of the K metal anode,resulting in uniform K deposition.As a result,this electrolyte achieves a high K plating/stripping Coulombic efficiency of 92.6%over 200 cycles and a stable discharging/charging for 100 cycles under the full battery configuration(K used as the anode and perylene-3,4,9,10-tetracarboxylic dianhydride used as the cathode).

Construction of Safety and Non-flammable Polyimide Separator Containing Carboxyl Groups for Advanced Fast Charing Lithium-ion Batteries

With the wide applications of lithium-ion batteries(LIBs)in electronic devices and electric vehicles,it is of great importance to improve their safety and electrochemical performance.Herein,soluble polyimides(PI)containing carboxyl groups(―COOH)were synthesized by a simple one-step method and PI separators with sponge-like,interpenetrating porous structures were prepared via non-solvent induced phase separation(NIPS).The obtained PI separators exhibited excellent thermal stability and fire-resistance properties,with the electrolyte uptake of 344%and good dimensional integrity in air at 200℃.The results showed that the lithium-ion transference number of the obtained PI separator could reach 0.48,which was much higher than that of the Celgard-2400 separator(0.38).The Li/LiFePO_(4) half-cell with the PI separator showed excellent cycle capability and high-rate performance with a high capacity of 121.80 mA·h·g^(-1) at 5 C,which was better than that of the cell with the Celgard-2400 separator(54.3 mA·h·g^(-1)),demonstrating the promising applications of this PI separators in LIBs.