Revealing the specific role of sulfide and nano-alumina in composite solid-state electrolytes for performance-reinforced ether-nitrile copolymers

Composite solid-state electrolytes represent a critical pathway that balances the interface compatibility and lithium-ion conductivity in all-solid-state batteries.The quest for stable and highly ion-conductive combinations between polymers and fillers is vital,but blind attempts are often made due to a lack of understanding of the mechanisms involved in the interaction between polymers and fillers.Herein,we employ in-situ polymerization to prepare a polymer based on an ether-nitrile copolymer with high cathode stability as the foundation and discuss the performance enhancement mechanisms of argyrodite and nano-alumina.With 1%content of sulfide interacting with the polymer at the two-phase interface,the local enhancement of lithium-ion migration capability can be achieved,avoiding the reduction in capacity due to the low ion conductivity of the passivation layer during cycling.The capacity retention after 50cycles at 0.5 C increases from 83.5%to 94.4%.Nano-alumina,through anchoring the anions and interface inhibition functions,eventually poses an initial discharge capacity of 136.8 m A h g^(-1)at 0.5 C and extends the cycling time to 1000 h without short-circuiting in lithium metal batteries.Through the combined action of dual fillers on the composite solid-state electrolyte,promising insights are provided for future material design.

A dynamic database of solid-state electrolyte(DDSE)picturing all-solid-state batteries

All-solid-state batteries(ASSBs)are a class of safer and higher-energy-density materials compared to conventional devices,from which solid-state electrolytes(SSEs)are their essential components.To date,investigations to search for high ion-conducting solid-state electrolytes have attracted broad concern.However,obtaining SSEs with high ionic conductivity is challenging due to the complex structural information and the less-explored structure-performance relationship.To provide a solution to these challenges,developing a database containing typical SSEs from available experimental reports would be a new avenue to understand the structureperformance relationships and find out new design guidelines for reasonable SSEs.Herein,a dynamic experimental database containing>600 materials was developed in a wide range of temperatures(132.40–1261.60 K),including mono-and divalent cations(e.g.,Li^(+),Na^(+),K^(+),Ag^(+),Ca^(2+),Mg^(2+),and Zn^(2+))and various types of anions(e.g.,halide,hydride,sulfide,and oxide).Data-mining was conducted to explore the relationships among different variates(e.g.,transport ion,composition,activation energy,and conductivity).Overall,we expect that this database can provide essential guidelines for the design and development of high-performance SSEs in ASSB applications.This database is dynamically updated,which can be accessed via our open-source online system.

Atom substitution of the solid-state electrolyte Li_(10)GeP_(2)S_(12)for stabilized all-solid-state lithium metal batteries

Solid-state electrolyte Li_(10)GeP_(2)S_(12)(LGPS)has a high lithium ion conductivity of 12 mS cm^(-1)at room temperature,but its inferior chemical stability against lithium metal anode impedes its practical application.Among all solutions,Ge atom substitution of the solid-state electrolyte LGPS stands out as the most promising solution to this interface problem.A systematic screening framework for Ge atom substitution including ionic conductivity,thermodynamic stability,electronic and mechanical properties is utilized to solve it.For fast screening,an enhanced model Dop Net FC using chemical formulas for the dataset is adopted to predict ionic conductivity.Finally,Li_(10)SrP_(2)S_(12)(LSrPS)is screened out,which has high lithium ion conductivity(12.58 mS cm^(-1)).In addition,an enhanced migration of lithium ion across the LSr PS/Li interface is found.Meanwhile,compared to the LGPS/Li interface,LSrPS/Li interface exhibits a larger Schottky barrier(0.134 eV),smaller electron transfer region(3.103?),and enhanced ability to block additional electrons,all of which contribute to the stabilized interface.The applied theoretical atom substitution screening framework with the aid of machine learning can be extended to rapid determination of modified specific material schemes.

Elucidating the suppression of lithium dendrite growth with a void-reduced anti-perovskite solid-state electrolyte pellet for stable lithium metal anodes

Solid-state lithium-metal batteries,with their high theoretical energy density and safety,are highly promising as a next-generation battery contender.Among the alternatives proposed as solid-state electrolyte,lithium-rich anti-perovskite(Li RAP)materials have drawn the most interest because of high theoretical Li^(+)conductivity,low cost and easy processing.Although solid-state electrolytes are believed to have the potential to physically inhibit the lithium dendrite growth,lithium-metal batteries still suffer from the lithium dendrite growth and thereafter the short circuiting.The voids in practical Li RAP pellets are considered as the root cause.Herein,we show that reducing the voids can effectively suppress the lithium dendrite growth.The voids in the pellet resulted in an irregular Li^(+)flux distribution and a poor interfacial contact with lithium metal anode;and hence the ununiform lithium dendrites.Consequently,the lithium-metal symmetric cell with void-reduced Li_(2)OHCl-HT pellet was able to display excellent cycling performance(750 h at 0.4 m A cm^(-2))and stability at high current density(0.8 m A cm^(-2)for 120 h).This study provides not only experimental evidence for the impact of the voids in Li RAP pellets on the lithium dendrite growth,but also a rational pellet fabrication approach to suppress the lithium dendrite growth.

A leap by the rise of solid-state electrolytes for Li-air batteries

Li-air batteries have attracted extensive attention because of their ultrahigh theoretical energy density. However, the potential safety hazard of flammable organic liquid electrolytes hinders their practical applications. Replacing liquid electrolytes with solidstate electrolytes(SSEs) is expected to fundamentally overcome the safety issues. In this work, we focus on the development and challenge of solid-state Li-air batteries(SSLABs). The rise of different types of SSEs, interfacial compatibility and verifiability in SSLABs are presented. The corresponding strategies and prospects of SSLABs are also proposed. In particular, combining machine learning method with experiment and in situ(or operando)techniques is imperative to accelerate the development of SSLABs.

MOF-based quasi-solid-state electrolyte for long-life Al-Se battery

Aluminum-selenium(Al-Se)batteries,which possess a high theoretical specific capacity of 1357 mA h g^(-1),represent a promising energy storage technology.However,they suffer from significant attenuation of capacity and low cycle life due to the shuttle effect.To mitigate the shuttle effect induced by soluble selenium chloroaluminate compound that tends to migrate towards the negative electrode,a quasi-solid-state Al-Se battery was fabricated through the synthesis of a multi-aperture structure quasisolid-state electrolyte(MOF@GPE)based on metal-organic framework(MOF)material and gel-polymer electrolyte(GPE).The high ionic conductivity(1.13×10^(-3)S cm^(-1))of MOF@GPE at room temperature,coupled with its wide electrochemical stability window(2.45 V),can facilitate ion transport kinetics and enhance the electrochemical performance of Al-Se batteries.The MOF@GPE-based quasi-solidstate Al-Se batteries exhibit outstanding long-life cycling stability,delivering a high specific discharge capacity of 548 mA h g^(-1)with a maintained discharge specific capacity of 345 mA h g^(-1)after 500 cycles at a current density of 200 mA g^(-1).The stable ion transmission and high ion transport kinetics in MOF@GPE can be attributed to the stable structure and permeable channel of MOF,which effectively captures the soluble selenium chloroaluminate compound and further restrains the shuttle effect,resulting in improved cycling performance.

Deep dive into anionic metal-organic frameworks based quasi-solid-state electrolytes

The development and application of high-capacity energy storage has been crucial to the global transition from fossil fuels to green energy.In this context,metal-organic frameworks(MOFs),with their unique 3D porous structure and tunable chemical functionality,have shown enormous potential as energy storage materials for accommodating or transporting electrochemically active ions.In this perspective,we specifically focus on the current status and prospects of anionic MOF-based quasi-solid-state-electrolytes(anionic MOF-QSSEs)for lithium metal batteries(LMBs).An overview of the definition,design,and properties of anionic MOF-QSSEs is provided,including recent advances in the understanding of their ion transport mechanism.To illustrate the advantages of using anionic MOF-QSSEs as electrolytes for LMBs,a thorough comparison between anionic MOF-QSSEs and other well-studied electrolyte systems is made.With these in-depth understandings,viable techniques for tuning the chemical and topological properties of anionic MOF-QSSEs to increase Li+conductivity are discussed.Beyond modulation of the MOFs matrix,we envisage that solvent and solid-electrolyte interphase design as well as emerging fabrication techniques will aid in the design and practical application of anionic MOF-QSSEs.

Bifunctional flame retardant solid-state electrolyte toward safe Li metal batteries

Solid polymer electrolytes(SPEs)are one of the most promising alternatives to flammable liquid electrolytes for building safe Li metal batteries.Nevertheless,the poor ionic conductivity at room temperature(RT)and low resistance to Li dendrites seriously hinder the commercialization of SPEs.Herein,we design a bifunctional flame retardant SPE by combining hydroxyapatite(HAP)nanomaterials with Nmethyl pyrrolidone(NMP)in the PVDF-HFP matrix.The addition of HAP generates a hydrogen bond network with the PVDF-HFP matrix and cooperates with NMP to facilitate the dissociation of Li TFSI in the PVDF-HFP matrix.Consequently,the prepared SPE demonstrates superior ionic conductivity at RT,excellent fireproof properties,and strong resistance to Li dendrites.The assembled Li symmetric cell with prepared SPE exhibits a stable cycling performance of over 1200 h at 0.2 m A cm^(-2),and the solid-state LiFePO_4||Li cell shows excellent capacity retention of 85.3%over 600 cycles at 0.5 C.

Tuning composite solid-state electrolyte interface to improve the electrochemical performance of lithium-oxygen battery

Thin and flexible composite solid-state electrolyte(SSE) is considered to be a prospective candidate for lithium-oxygen(Li-O_(2)) batteries with the aim to address the problems of unsatisfied safety, terrible durability as well as inferior electrochemical performance. Herein, in order to improve the safety and durability, a succinonitrile(SN) modified composite SSE is proposed. In this SSE, SN is introduced for eliminating the boundary between ceramic particles, increasing the amorphous region of polymer and ensuring fast ionic transport. Subsequently, the symmetric battery based on the proposed SSE achieves a long cycle life of 3000 h. Moreover, the elaborate cathode interface through the SN participation effectively reduces the barriers to the combination between lithium ions and electrons, facilitating the corresponding electrochemical reactions.As a result, the solid-state Li-O_(2)battery based on this SSE and tuned cathode interface achieves improved electrochemical performance including large specific capacity over 12,000 m Ah g^(-1), enhanced rate capacity as well as stable cycle life of 54 cycles at room temperature. This ingenious design provides a new orientation for the evolution of solid-state Li-O_(2)batteries.

Solid-state electrolytes for solid-state lithium-sulfur batteries:Comparisons,advances and prospects

Compared with other secondary batteries,lithium-sulfur batteries(LSBs)have unparalleled advantages such as high energy density,low cost,etc.In liquid LSB systems,it is extremely easy to cause severe‘‘shuttle effecto and safety issues.Hence,the development of solid-state LSBs(SSLSBs)has been attracting much more attention.As the most essential part of the SSLSBs,the solid-state electrolyte(SSE)has received significant attention from researchers.In this review,we concentrate on discussing the core of SSLSBs,which is the SSE.Moreover,we also highlight the differences in the properties of the different SSEs,which are polymer-based electrolytes and ceramic-based electrolytes.In addition,the challenges and advances in different types of SSEs are also compared and described systematically.Furthermore,the prospects for new SSE systems and the design of effective SSE structures to achieve highperformance SSLSBs are also discussed.Thus,this review is expected to give readers a comprehensive and systematic understanding of SSEs for SSLSBs.

Recent advances on quasi-solid-state electrolytes for supercapacitors

Solid-state and quasi-solid-state electrolytes have been attracting the scientific community’s attention in the last decade. These electrolytes provide significant advantages, such as the absence of leakage and separators for devices and safety for users. They also allow the assembly of stretchable and bendable supercapacitors. Comparing solid-state to quasi-solid-states, the last provides the most significant energy and power densities due to the better ionic conductivity. Our goal here is to present recent advances on quasisolid-state electrolytes, including gel-polymer electrolytes. We reviewed the most recent literature on quasi-solid-state electrolytes with different solvents for supercapacitors. Organic quasi-solid-state electrolytes need greater attention once they reach an excellent working voltage window greater than 2.5 V.Meanwhile, aqueous-based solid-state electrolytes have a restricted voltage window to less than 2 V. On the other hand, they are easier to handle, provide greater ionic conductivity and capacitance. Recent water-in-salt polymer-electrolytes have shown stability as great as 2 V encouraging further development in aqueous-based quasi-solid-state electrolytes. Moreover, hydrophilic conductive polymers have great commercial appeal for bendable devices. Thus, these electrolytes can be employed in flexible and bendable devices, favoring the improvement of portable electronics and wearable devices(376 references were evaluated and summarized here).

Effects of Heat Treatment and Additive LiF on the Properties of Solid-State Electrolyte of Li_(1.5)Al_(0.5)Ge_(1.5)(PO_(4))_(3)

A solid electrolyte of LAGP[Li_(1.5)Al_(0.5)Ge_(1.5)(PO_(4))_(3)]contained 0.5 wt%Li F was prepared by using low-volatile raw materials.The effects of different heat treatment conditions(750–900°C,4–10 h)and additive(Li F)on the ionic conductivity,structural morphology,and crystal transformation process were investigated in detail.EIS(electrochemical impedance spectroscopies)showed that the ionic conductivity of LAGP contained 0.5 wt%Li F had a highest value of 3.17×10^(-4)S cm^(-1)with low activation energy(0.31 e V)after treating 825°C for 6 h,more than LAGP of 2.45×10^(-4)S cm^(-1).DSC analysis and SEM images indicated that adding a small amount of Li F to LAGP not only can lower the glass transition temperature(from 513°C to507°C)and crystallization temperature(from 622°C to 605°C),but also can modify the grain boundary and increase the relative density of LAGP(from 95.8%to 97.7%).

A high-performance rechargeable Li–O_2 battery with quasi-solid-state electrolyte

A novel transparent and soft quasi-solid-state electrolyte （QSSE） was proposed and fabricated, which consists of ionic liquid （PYR14TFSI） and nano-fumed silica. The QSSE demonstrates high ionic conductivity of 4.6× 10-4 S/cm at room temperature and wide electrochemical stability window of over 5 V. The Li-O2 battery using such quasi-solidstate electrolyte exhibits a low charge-discharge overpotential at the first cycle and excellent long-term cyclability over 500 cycles.

Research progress in electrospinning engineering for all-solid-state electrolytes of lithium metal batteries

Owing to safety issue and low energy density of liquid lithium-ion batteries(LIBs),all-solid-state lithium metal batteries(ASLMBs)with unique all-solid-state electrolytes(SEs)have attracted wide attentions.This arises mainly from the advantages of the SEs in the suppression of lithium dendrite growth,long cycle life,and broad working temperature range,showing huge potential applications in electronic devices,electric vehicles,smart grids,and biomedical devices.However,SEs suffer from low lithiumion conductivity and low mechanical integrity,slowing down the development of practical ASLMBs.Nanostructure engineering is of great efficiency in tuning the structure and composition of the SEs with improved lithium-ion conductivity and mechanical integrity.Among various available technologies for nanostructure engineering,electrospinning is a promising technique because of its simple operation,cost-effectiveness,and efficient integration with different components.In this review,we will first give a simple description of the electrospinning process.Then,the use of electrospinning technique in the synthesis of various SEs is summarized,for example,organic nanofibrous matrix,organic/inorganic nanofibrous matrix,and inorganic nanofibrous matrix combined with other components.The current development of the advanced architectures of SEs through electrospinning technology is also presented to provide references and ideas for designing high-performance ASLMBs.Finally,an outlook and further challenges in the preparation of advanced SEs for ASLMBs through electrospinning engineering are given.

Development of solid-state electrolytes for sodium-ion battery–A short review

All-solid-state sodium-ion battery is regarded as the next generation battery to replace the current commercial lithium-ion battery, with the advantages of abundant sodium resources, low price and high-level safety. As one critical component in sodium-ion battery, solid-state electrolyte should possess superior operational safety and design simplicity, yet reasonable high room-temperature ionic conductivity. This paper gives a comprehensive review on the recent progress in solid-state electrolyte materials for sodium-ion battery, including inorganic ceramic/glass-ceramic, organic polymer and ceramic-polymer composite electrolytes, and also provides a comparison of the ionic conductivity in various solid-state electrolyte materials. The development of solid-state electrolytes suggests a bright future direction: all solid-state sodium-ion battery could be fully used to power all electric road vehicles, portable electronic devices and large-scale grid support.

Solid-State Electrolytes for Lithium-Sulfur Batteries

Secondary lithium-sulfur batteries have attracted extensive attention due to their high energy density,low cost and environment friendly.However,the"shuttle effect"of polysulfides dissolved in liquid electrolytes leads to a decrease of the cell Coulomb efficiency(CE).Therefore,researchers have used solid electrolytes instead of traditional liquid electrolytes and separators to suppress the"shuttle effect"of polysulfides and the growth of lithium dendrites.The progress in electrolytes for solid-state lithium-sulfur batteries including solid-state polymer,inorganic,and composite electrolytes to solve the issues is summarized.

Recent research progress on quasi-solid-state electrolytes for dye-sensitized solar cells

Dye-sensitized solar cells （DSSCs） are the most promising, low cost and most extensively investigated solar cells. They are famous for their clean and efficient solar energy conversion. Nevertheless this, long-time sta- bility is still to be acquired. In recent years research on solid and quasi-solid state electrolytes is extensively in- creased. Various quasi-solid electrolytes, including composites polymer electrolytes, ionic liquid electrolytes, thermoplastic polymer electrolytes and thermosetting polymer electrolytes have been used. Performance and stability of a quasi-solid state electrolyte are between liquid and solid electrolytes. High photovoltaic performances of QS-DSSCs along better long-term stability can be obtained by designing and optimizing quasi-solid electrolytes. It is a prospective candidate for highly efficient and stable DSSCs.

Pancake-Like MOF Solid-State Electrolytes with Fast Ion Migration for High-Performance Sodium Battery

Solid-state electrolyte(SSE)of the sodium-ion battery have attracted tremendous attention in the next generation energy storage materials on account of their wide electrochemical window and thermal stability.However,the high interfacial impedance,low ion transference number and complex preparation process restrict the application of SSE.Herein,inspired by the excellent sieving function and high specific surface area of red blood cells,we obtained a solid-like electrolyte(SLE)based on the combination of the pancake-like metal-organic framework(MOF)with liquid electrolyte,possessing a high ionic conductivity of 6.60×10^(-4) S cm^(−1),and excellent sodium metal compatibility.In addition,we investigated the ion restriction effect of MOF’s apertures size and special functional groups,and the ion transference number increased from 0.16 to 0.33.Finally,the assembled Na_(0.44)MnO_(2)//SLE//Na full batteries showed no obvious capacity decrease after 160 cycles.This material design of SLE in our work is an important key to obtain fast ion migration SLE for high-performance sodium-ion batteries.

Self-Assembled in-Plane-Gate Thin-Film Transistors Gated by WOx Solid-State Electrolytes

Low-voltage WOx gated indium-zinc-oxide thin-film transistors(TFTs)with in-plane-gate structures are fabricated by using an extremely simplified one-shadow mask method at room temperature.The proton conductive WOx solid-state electrolyte is demonstrated to form an electric-double-layer(EDL)effect associated with a huge capacitance of 0.51μF/cm^(2).The special EDL capacitance of the WOx electrolyte is also extended to novel in-plane-gate structure TFTs as the gate dielectric,reducing the operating voltage to 1.8 V.Such TFTs operate at n-type depletion mode with a threshold voltage of -0.5 V,saturation electron mobility of 13.2 cm^(2)/V·s,ON/OFF ratio of 1.7×10^(6),subthreshold swing of 110 mV/dec,and low leakage current less than 7 nA.The hysteresis window of the transfer curves is also explained by an unique reaction within the WOx electrolyte.

Double-layer solid-state electrolyte enables compatible interfaces for high-performance lithium metal batteries

Solid-state lithium metal batteries are promising next-generation batteries for both micro-scale integrated electronic devices and macro-scale electric vehicles.However,electrochemical incompatibility between electrolyte and electrodes causes continuous performance degradation.Here,we report a unique design of a double-layer composite solid-state electrolyte(D-CSE),where each layer,composed of both polymer and ceramics,is electrochemically compatible with its contacting electrode(Li anode or LiCoO_(2)cathode).The D-CSE has a small thickness(50μm),high thermal stability(up to 160℃ without noticeable deformation),and good flexibility even at a high ceramics content(66.7 wt%).Large-area selfstanding film can be obtained by a facile coating route.The electrolyte/electrode interface can be further enhanced via forming a soft interface by in-situ polymerization.Quasi-solid-state Li|D-CSE|LiCoO_(2)coin cells with the cathode-supported D-CSE can deliver a high initial discharge capacity of 134 mAh g^(-1) and a high capacity retention of 83%after 200 cycles at 0.5 C and 60℃.Quasi-solid-state Li|D-CSE|LiCoO_(2)pouch cells(designed capacity 8.6 mAh)with the self-standing D-CSE have a high retention of80%after 180 cycles at 2 mA charge and 4 mA discharge.At a high cathode loading(19.1 mg cm^(-2)),the Li|D-CSE|LiCoO_(2)pouch cell still can be stably cycled,and can withstand abuse tests of folding,cutting and nail penetration,indicating practical applications of the D-CSE.