All-solid-state lithium batteries with inorganic solid electrolytes:Review of fundamental science

The scientific basis of all-solid-state lithium batteries with inorganic solid electrolytes is reviewed briefly, touching upon solid electrolytes, electrode materials, electrolyte/electrode interface phenomena, fabrication, and evaluation. The challenges and prospects are outlined as well.

Structure designing,interface engineering,and application prospects for sodium-ion inorganic solid electrolytes

All-solid Na-ion batteries(ASNIBs)present significant potential for integration into large-scale energy storage systems,capitalizing on their abundant raw materials,exemplary safety,and high energy density.Among the pivotal components propelling the advancement of ASNIBs,inorganic solid electrolytes(ISEs)have garnered substantial attention in recent years due to their high ionic conductivity(σ),wide electrochemical stability window(ESW),and high shear modulus.Herein,this review systematically encapsulates the latest strides in Na-ion ISEs,furnishing a comprehensive panorama of various ISE systems along with their interface engineering strategies against the electrodes.The prime focus resides in accentuating key strategies for refining ion conduction properties and interfacial compatibility of ISEs through structure design and interface modification.Furthermore,the review explores the foremost challenges and prospects inherent to sodium-ion ISEs,striving to deepen our understanding of how to engineer more robust and efficient ISEs and interface stability,poised for the forthcoming era of advanced ASNIBs.

A critical review on composite solid electrolytes for lithium batteries:Design strategies and interface engineering

The rapid development of new energy vehicles and 5G communication technologies has led to higher demands for the safety,energy density,and cycle performance of lithium-ion batteries as power sources.However,the currently used liquid carbonate compounds in commercial lithium-ion battery electrolytes pose potential safety hazards such as leakage,swelling,corrosion,and flammability.Solid electrolytes can be used to mitigate these risks and create a safer lithium battery.Furthermore,high-energy density can be achieved by using solid electrolytes along with high-voltage cathode and metal lithium anode.Two types of solid electrolytes are generally used:inorganic solid electrolytes and polymer solid electrolytes.Inorganic solid electrolytes have high ionic conductivity,electrochemical stability window,and mechanical strength,but suffer from large solid/solid contact resistance between the electrode and electrolyte.Polymer solid electrolytes have good flexibility,processability,and contact interface properties,but low room temperature ionic conductivity,necessitating operation at elevated temperatures.Composite solid electrolytes(CSEs) are a promising alternative because they offer light weight and flexibility,like polymers,as well as the strength and stability of inorganic electrolytes.This paper presents a comprehensive review of recent advances in CSEs to help researchers optimize CSE composition and interactions for practical applications.It covers the development history of solid-state electrolytes,CSE properties with respect to nanofillers,morphology,and polymer types,and also discusses the lithium-ion transport mechanism of the composite electrolyte,and the methods of engineering interfaces with the positive and negative electrodes.Overall,the paper aims to provide an outlook on the potential applications of CSEs in solid-state lithium batteries,and to inspire further research aimed at the development of more systematic optimization strategies for CSEs.

Safe and Stable Lithium Metal Batteries Enabled by an Amide-Based Electrolyte

The formation of lithium dendrites and the safety hazards arising from flammable liquid electrolytes have seriously hindered the development of high-energy-density lithium metal batteries.Herein,an emerging amide-based electrolyte is proposed,containing LiTFSI and butyrolactam in different molar ratios.1,1,2,2-Tetrafluoroethyl-2,2,3,3-tetrafluoropropylether and fluoroethylene carbonate are introduced into the amide-based electrolyte as counter solvent and additives.The well-designed amide-based electrolyte possesses nonflammability,high ionic conductivity,high thermal stability and electrochemical stability(>4.7 V).Besides,an inorganic/organic-rich solid electrolyte interphase with an abundance of LiF,Li3N and Li-N-C is in situ formed,leading to spherical lithium deposition.The formation mechanism and solvation chemistry of amide-based electrolyte are further inves-tigated by molecular dynamics simulations and density functional theory.When applied in Li metal batteries with LiFePO4 and LiMn2O4 cathode,the amide-based electrolyte can enable stable cycling performance at room temperature and 60℃.This study provides a new insight into the development of amide-based electrolytes for lithium metal batteries.

A review of solid electrolytes for safe lithium-sulfur batteries

Due to the high specific capacity, low cost, and environmental friendliness, lithium-sulfur batteries hold great potential to become the mainsiay of next-generation energy storage system. Regarding the composition of sulfur/carbon in cathode, flammable organic liquid electrolyte, and lithium metal anode, great concerns about the safety have been raised. Hence solid-electrolyte-based lithium-sulfur batteries, as one alternative route for safe batteries, are highly interested. This review highlights the recent research progress of lithium-sulfur batteries with solid electrolytes. Both sulfide solid electrolytes and oxide solid electrolytes are included. The sulfide solid electrolytes are mainly employed in all-solid-state lithium-sulfur batteries, while the oxide solid electrolytes are applied in hybrid electrolyte for lithium-sulfur batteries. The challenges and perspectives in this field are also featured on the basis of its current progress.

Solid-state electrolytes for safe rechargeable lithium metal batteries:a strategic view

Despite the efforts devoted to the identification of new electrode materials with higher specific capacities and electrolyte additives to mitigate the well-known limitations of current lithium-ion batteries,this technology is believed to have almost reached its energy density limit.It suffers also of a severe safety concern ascribed to the use of flammable liquid-based electrolytes.In this regard,solid-state electrolytes(SSEs)enabling the use of lithium metal as anode in the so-called solid-state lithium metal batteries(SSLMBs)are considered as the most desirable solution to tackle the aforementioned limitations.This emerging technology has rapidly evolved in recent years thanks to the striking advances gained in the domain of electrolyte materials,where SSEs can be classified according to their core chemistry as organic,inorganic,and hybrid/composite electrolytes.This strategic review presents a critical analysis of the design strategies reported in the field of SSEs,summarizing their main advantages and disadvantages,and providing a future perspective toward the rapid development of SSLMB technology.

Li-rich channels as the material gene for facile lithium diffusion in halide solid electrolytes

Halide solid electrolytes have attracted intense research interest recently for application in all-solid-state lithiumion batteries. Herein, we present a systematic first-principles study of the Li3MX6 (M: multivalent cation;X:halogen anion) halide family that unveils the link between Li-rich channels and ionic conductivity, highlightingthe former as a material gene in these compounds. By screening a total of 180 halides for those with highthermodynamic stability, wide electrochemical window, low chemical reactivity, and decent Li-ion conductivity,we identify seven unexplored candidates for solid electrolytes. From these halides and another four prototypecompounds, we discover that the facile Li diffusion is rooted in the availability of diffusion pathways which canavoid direct connection with M cations-that is, where the local environment is Li-rich. These findings shed lighton strategies for regulating cation and anion frameworks to establish Li-rich channels in the design of high-performance inorganic solid electrolytes.

Thermal Behavior and Lithium Ion Conductivity of L_2O-Al_2O_3-TiO_2-SiO_2-P_2O_5 Glass-ceramics

A lithium ion conductive solid electrolyte, L20-AI203-TiO2-SiO2-P20s glass with NASICON- type structure have been synthesized and transformed into glass-ceramic through thermal-treatment at various temperatures from 700 to 1 000 ~C for 12 h. The differential scanning calorimetry （DSC）, X-ray diffraction （XRD）, scanning electron microscopy （SEM） and complex impedance techniques were employed to characterize the samples. The experimental results indicated that the capability of glass forming in this system is superior to that of L20-A1203-TiO2-PzO~. The glass has an amorphous structure and resultant glass-ceramic mainly consisting of LiTi2（PO4）3 phases. Impurity phases AIPO4, TiO2, TiP207 and unidentified phase were observed. With the enhanced heat-treatment temperature, grain grew gradually and lithium ion conductivity of glass-ceramics increased accordingly, the related impedance semicircles were depressed gradually and even disappeared, which could be analytically explained by the coordinate action of the ＇Constant phase element＇ （CPE） model and the ＇Concept of Mismatch and Relaxation＇ model （CMR）. When the sample is devitrified at 1 000 ~C, the maximum room temperature lithium ion conductivity comes up to 4.1 x 10-4 S/cm, which is suitable for the application as an electrolyte of all-solid-state lithium batteries.

Revealing milling durations and sintering temperatures on conductivity and battery performances of Li_(2.25)Zr_(0.75)Fe_(0.25)Cl_(6)electrolyte

Halide electrolytes in solid-state batteries with excellent oxidative stability and high ionic conductivity have been well reported recently.However,the high-cost rare-earth elements and long duration of highrotation milling procure are the major obstacles.Herein,we have successfully synthesized the low cost Li_(2.25)Zr_(0.75)Fe_(0.25)Cl_(6)electrolyte consisting of abundant elements with comparable Li-ion conductivity in a short milling duration of 4 h.Phase transition of the annealed sample was also carefully investigated.Li Ni_(0.6)Co_(0.2)Mn_(0.2)O_(2)/Li_(2.25)Zr_(0.75)Fe_(0.25)Cl_(6)/Li_(5.5)PS_(4.5)Cl_(1.5)/In-Li batteries using different halide electrolytes were constructed and cycled at different voltage windows.Solid-state battery using Li_(2.25)Zr_(0.75)Fe_(0.25)Cl_(6)electrolyte obtained from long milling duration delivers higher discharge capacities and superior capacity retention than shorter milling time between 3.0 and 4.3 V.It delivers much higher discharge capacity when cycled at elevated temperature(60℃)and suffers fast capacity degradation when the upper cut-off voltage increases to 4.5 V at the same current density.This work provides an efficiency synthesis strategy for halide solid electrolyte and studies its applications in all-solid-state batteries in a wide temperature range.