Rational design of F,N-rich artificial interphase via chemical prelithiation initiation strategy enabling high coulombic efficiency and stable micro-sized SiO anodes

Silicon monoxide(SiO)is regarded as a potential candidate for anode materials of lithium-ion batteries(LIBs).Unfortunately,the application of SiO is limited by poor initial Coulombic efficiency(ICE)and unsteady solid electrolyte interface(SEI),which induce low energy,short cycling life,and poor rate properties.To address these drawbacks of SiO,we achieve in-situ construction of robust and fast-ion conducting F,N-rich SEI layer on prelithiated micro-sized SiO(P-μSiO)via the simple and continuous treatment ofμSiO in mild lithium 4,4′-dimethylbiphenyl solution and nonflammable hexafluorocyclotriphosphazene solution.Chemical prelithiation eliminates irreversible capacity through pre-forming inactive lithium silicates.Meanwhile,the symbiotic F,N-rich SEI with good mechanical stability and fast Li^(+)permeability is conductive to relieve volume expansion ofμSiO and boost the Li+diffusion kinetics.Consequently,the P-μSiO realizes an impressive electrochemical performance with an elevated ICE of 99.57%and a capacity retention of 90.67%after 350 cycles.Additionally,the full cell with P-μSiO anode and commercial LiFePO_(4) cathode displays an ICE of 92.03%and a high reversible capacity of 144.97 mA h g^(-1).This work offers a general construction strategy of robust and ionically conductive SEI for advanced LIBs.

Facilitating prelithiation of silicon carbon anode by localized high-concentration electrolyte for high-rate and long-cycle lithium storage

The commercialization of silicon-based anodes is affected by their low initial Coulombic efficiency(ICE)and capacity decay,which are attributed to the formation of an unstable solid electrolyte interface(SEI)layer.Herein,a feasible and cost-effective prelithiation method under a localized highconcentration electrolyte system(LHCE)for the silicon-silica/graphite(Si-SiO_(2)/C@G)anode is designed for stabilizing the SEI layer and enhancing the ICE.The thin SiO_(2)/C layers with-NH_(2) groups covered on nano-Si surfaces are demonstrated to be beneficial to the prelithiation process by density functional theory calculations and electrochemical performance.The SEI formed under LHCE is proven to be rich in ionic conductivity,inorganic substances,and flexible organic products.Thus,faster Li+transportation across the SEI further enhances the prelithiation effect and the rate performance of Si-SiO_(2)/C@G anodes.LHCE also leads to uniform decomposition and high stability of the SEI with abundant organic components.As a result,the prepared anode shows a high reversible specific capacity of 937.5 mAh g^(-1)after 400 cycles at a current density of 1 C.NCM 811‖Li-SSGLHCE full cell achieves a high-capacity retention of 126.15 mAh g^(-1)at 1 C over 750 cycles with 84.82%ICE,indicating the great value of this strategy for Si-based anodes in large-scale applications.

Recent progress and perspectives on silicon anode:Synthesis and prelithiation for LIBs energy storage

The ever-increasing environmental/energy crisis as well as the rapid upgrading of mobile devices had stimulated intensive research attention on promising alternative energy storage and conversion devices.Among these devices,alkali metal ion batteries,such as lithium-ion batteries(LIBs) had attracted increasing research attention due to its several advantages including,environmental friendliness,high power density,long cycle life and excellent reversibility.It had been widely used in consumer electronics,electric vehicles,and large power grids et ac.Silicon-based(silicon and their oxides,carbides) anodes had been widely studied.Its several advantages including low cost,high theoretical capacity,natural abundance,and environmental friendliness,which shows great potential as anodes of LIBs.In this review,we summarized the recently progress in the synthetic method of silicon matrix composites.The empirical method for prelithiation of silicon-based materials were also provided.Further,we also reviewed some novel characterization methods.Finally,the new design,preparation methods and properties of these nano materials were reviewed and compared.We hoped that this review can provide a general overview of recent progress and we briefly highlighted the current challenges and prospects,and will clarify the future trend of silicon anode LIBs research.

Progress and challenges of prelithiation technology for lithium-ion battery

Prelithiation technology is widely considered a feasible route to raise the energy density and elongate the cycle life of lithium-ion batteries.The principle of prelithiation is to introduce extra active Li ions in the battery so that the lithium loss during the first charge and long-term cycling can be compensated.Such an effect does not need to change the major electrode material or battery structure and is compatible with the majority of current lithium-ion battery production lines.At this stage,various prelithiation methods have been reported,some of which are already in the pilot-scale production stage.But there is still no definitive development roadmap for prelithiation.In this review,we first introduce the influence of prelithiation on electrochemical performance from a theoretical point of view and then compare the pros and cons of different prelithiation methods in different battery manufacturing stages.Finally,we discuss the challenges and future development trends of prelithiation.We aim to build up a bridge between academic research and industrial application.Some engineering problems in the promotion of prelithiation technique are extensively discussed,including not only the implementation of prelithiation but also some collateral issues on battery designing and management.

Regulating the Solvation Structure of Li^(+) Enables Chemical Prelithiation of Silicon-Based Anodes Toward High-Energy Lithium-Ion Batteries

The solvation structure of Li^(+) in chemical prelithiation reagent plays a key role in improving the low initial Coulombic efficiency(ICE) and poor cycle performance of silicon-based materials. Never theless, the chemical prelithiation agent is difficult to dope active Li^(+) in silicon-based anodes because of their low working voltage and sluggish Li^(+) diffusion rate. By selecting the lithium–arene complex reagent with 4-methylbiphenyl as an anion ligand and 2-methyltetrahydrofuran as a solvent, the as-prepared micro-sized Si O/C anode can achieve an ICE of nearly 100%. Interestingly, the best prelithium efficiency does not correspond to the lowest redox half-potential(E_(1/2)), and the prelithiation efficiency is determined by the specific influencing factors(E_(1/2), Li^(+) concentration, desolvation energy, and ion diffusion path). In addition, molecular dynamics simulations demonstrate that the ideal prelithiation efficiency can be achieved by choosing appropriate anion ligand and solvent to regulate the solvation structure of Li^(+). Furthermore, the positive effect of prelithiation on cycle performance has been verified by using an in-situ electrochemical dilatometry and solid electrolyte interphase film characterizations.

Prelithiation strategies for silicon-based anode in high energy density lithium-ion battery

Green energy storage devices play vital roles in reducing fossil fuel emissions and achieving carbon neutrality by 2050.Growing markets for portable electronics and electric vehicles create tremendous demand for advanced lithium-ion batteries(LIBs)with high power and energy density,and novel electrode material with high capacity and energy density is one of the keys to next-generation LIBs.Silicon-based materials,with high specific capacity,abundant natural resources,high-level safety and environmental friendliness,are quite promising alternative anode materials.However,significant volume expansion and redundant side reactions with electrolytes lead to active lithium loss and decreased coulombic efficiency(CE)of silicon-based material,which hinders the commercial application of silicon-based anode.Prelithiation,preembedding extra lithium ions in the electrodes,is a promising approach to replenish the lithium loss during cycling.Recent progress on prelithiation strategies for silicon-based anode,including electrochemical method,chemical method,direct contact method,and active material method,and their practical potentials are reviewed and prospected here.The development of advanced Si-based material and prelithiation technologies is expected to provide promising approaches for the large-scale application of silicon-based materials.

Practical evaluation of prelithiation strategies for next-generation lithium-ion batteries

With the increasing market demand for high-performance lithium-ion batteries with high-capacity electrode materials,reducing the irreversible capacity loss in the initial cycle and compensating for the active lithium loss during the cycling process are critical challenges.In recent years,various prelithiation strategies have been developed to overcome these issues.Since these approaches are carried out under a wide range of conditions,it is essential to evaluate their suitability for large-scale commercial applications.In this review,these strategies are categorized based on different battery assembling stages that they are implemented in,including active material synthesis,the slurry mixing process,electrode pretreatment,and battery fabrication.Furthermore,their advantages and disadvantages in commercial production are discussed from the perspective of thermodynamics and kinetics.This review aims to provide guidance for the future development of prelithiation strategies toward commercialization,which will potentially promote the practical application of next-generation high-energy-density lithium-ion batteries.

Bifunctional Li6CoO4 serving as prelithiation reagent and pseudocapacitive electrode for lithium ion capacitors

Lithium ion capacitors(LICs)have been widely used as energy storage devices due to their high energy density and high power density.For LICs,pre-lithiation of negative electrode is necessary.In this work,we employ a bifunctional Li6CoO4(LCO)as cathodic pre-lithiation reagent to improve the electrochemical performance of LICs.The synthesized LCO exhibited high first charge specific capacity of 721 mAh g-1and extremely low initial coulombic efficiency of 3.19%,providing sufficient Li+ for the pre-lithiation of negative electrode in the first charge.Simultaneously,Li6–xCoOy is generated from LCO during the first charge process,which exhibits pseudocapacitive property and contributes to capacity in form of surface capacitance during subsequent cycles,increasing the capacity of capacitive positive electrode.With the appropriate amounts of addition to the positive side in LICs,this bifunctional prelithiation reagent LCO shows significantly improved the electrochemical performance with the energy density of 78.5 Wh kg-1after 300 cycles between 2.0 and 4.2 V at 250 mA g-1.

Prelithiation Enhances Cycling Life of Lithium-Ion Batteries:A Mini Review

During the last decade,the rapid development of lithium-ion battery(LIB)energy storage systems has provided significant support for the efficient operation of renewable energy stations.In the coming years,the service life demand of energy storage systems will be further increased to 30 years from the current 20 years on the basis of the equivalent service life of renewable energy stations.However,the life of the present LIB is far from meeting such high demand.Therefore,research on the next-generation LIB with ultra-long service life is imminent.Prelithiation technology has been widely studied as an important means to compensate for the initial coulombic efficiency loss and improve the service life of LIBs.This review systematically summarized the different prelithiation methods from anode and cathode electrodes.Moreover,the large-scale industrialization challenge and the possibility of the existing prelithiation technology are analyzed,based on three key parameters:industry compatibility,prelithiation efficiency,and energy density.Finally,the future trends of improvement in LIB performance by other overlithiated cathode materials are presented,which gives a reference for subsequent research.

Prelithiation design for suppressing delamination in lithium-ion battery electrodes

Prelithiation has been intensively investigated in high-capacity lithiumion batteries(LIBs).However,the optimization of prelithiation degrees for long service life of LIBs still remains a challenge.The positive effect of prelithiation on suppressing degradation of LIBs,besides directly pursuing the high first Coulomb efficiency which has been widely reported in the literature,is revealed and discussed based on an analytical model focusing on the interfacial delamination in electrodes.For full charge-discharge cycling,well-designed prelithiation can effectively suppress the delamination and reduce the debonding size by approximately 25%,compared with the case without prelithiation.For the strategy combining partial charge-discharge cycling and prelithiation,the largest reversible capacity without debonding can be significantly improved by approximately100%with well-designed prelithiation.This work is expected to provide a prelithiation design principle and further improve the mechanical stability of LIB electrodes.

Lithium sulfide:a promising prelithiation agent for high-performance lithium-ion batteries

Lithium-ion batteries are widely used in portable electronics and electric vehicles due to their high energy density,stable cycle life,and low self-discharge.However,irreversible lithium loss during the formation of the solid electrolyte interface greatly impairs energy density and cyclability.To compensate for the lithium loss,introducing an external lithium source,that is,a prelithiation agent,is an effective strategy to solve the above problems.Compared with other prelithiation strategies,cathode prelithiation is more cost-effective with simpler operation.Among various cathode prelithiation agents,we first systematically summarize the recent progress of Li_(2)S-based prelithiation agents,and then propose some novel strategies to tackle the current challenges.This review provides a comprehensive understanding of Li_(2)S-based prelithiation agents and new research directions in the future.

Efficient Chemical Prelithiation with Modificatory Li^(+) Solvation Structure Enabling Spatially Homogeneous SEI toward High Performance SiO_(x) Anode

Chemical prelithiation is widely proven to be an effective strategy to address the low initial coulombic efficiency(ICE)of promising SiO_(x) anode.Though the reagent composition has been widely explored,the Li^(+) solvation structure,which practically plays the cornerstone role in the prelithiation ability,rate,uniformility,has rarely been explored.A novel environmentally-friendly reagent with weak solvent cyclopentyl methyl ether(CPME)is proposed that enables both improved ICE and spatial homogeneous solid electrolyte interphase(SEl).And the prelithiation behavior and mechanism were explored focused on the Li^(+) solvation structure.Both theoretical investigation and spectroscopic results suggest that weak solvent feature of CPME reduces the solvent coordination number and decreases the Li^(+) desolvation energy.

Recent advances and perspectives on prelithiation strategies for lithium-ion capacitors

Lithium-ion capacitors(LICs),consisting of a capacitor-type material and a battery-type material together with organic electrolytes,are the state-of-the-art electrochemical energy storage devices compared with supercapacitors and batteries.Owing to their unique characteristics,LICs received a lot of attentions,and great progresses have been achieved,especially in the exploration of cathode and anode materials.Prelithiation techniques are regarded as indispensable procedures for LICs systems,which can compensate for the initial irreversible capacity loss,increase the Li^(+)concentration in the electrolyte,raise the working voltage and resolve the safety and cycle stability issues;however,its research progress is slow,and there is not enough attention until now.In this overview,we look into the ongoing processes on the recent development of prelithiation technologies,especially in organic electrolyte consumption-type LICs.In particular,some prelithiation strategies for LICs are summarized and discussed in detail,including the ex situ electrochemical method,in situ electrochemical method,and cathode prelithiation additives method.Moreover,we propose some unresolved challenges and prospects for prelithiation technologies from the basic research ideas and future key research directions.This work aims to bring up new insights to reassess the significance of premetallation strategies for advanced hybrid-ion capacitors based on the currently proposed prelithiation strategies.

Revealing the interface-rectifying functions of a Li-cyanonaphthalene prelithiation system for SiO electrode

Chemical prelithiation is regarded as a crucial method for improving the initial Coulombic efficiency(ICE)of Li-storage anodes.Herein,a substituent-engineered Li-cyanonaphthalene chemical prelithiation system is designed to simultaneously enhance the ICE and construct a multifunctional interfacial film for SiO electrodes.X-ray photoelectron spectroscopy(XPS),electron energy-loss spectroscopy(EELS),nuclear magnetic resonance(NMR)spectroscopy and atomic force microscopy(AFM)prove that the Licyanonaphthalene prelithiation reagent facilitates the formation of a rectified solid electrolyte interface(SEI)film in two ways:(1)generation of a gradient SEI film with an organic outer layer(dense Ncontaining organics,ROCO_(2)Li)and an inorganic LiF-enriched inner layer;(2)homogenization of the horizontal distribution of the composition,mechanical properties and surface potential.As a result,the prelithiated SiO electrode exhibits an ICE above 100%,enhanced CEs during cycling,better cycle stability and inhibition of lithium dendrite formation in the overcharged state.Notably,the prelithiated hard carbon/SiO(9:1)‖LHCoO_(2) cell displays an enhancement in the energy density of 62.3%.

Molten-LiCl induced thermochemical prelithiation of SiOx:Regulating the active Si/O ratio for high initial Coulombic efficiency

The low initial Coulombic efficiency(ICE)of SiOx anode caused by the irreversible generation of LiySiOz and Li20 during lithiation process limits its application for high energy-density lithium-ion batteries.Herein,we report a molten-salt-induced thermochemical.prelithiation strategy for regulating the electrochemically active Si/O ratio of SiOx and thus enhancing ICE through thermal treatment of pre-synthesized LiNH2-coated SiOx in molten LiCl at 700℃.Bulk SiOx micro-particle was transformed into pomegranatelike prelithiated micro-cluster composite(M-Li-SiOx)with SiOx core and outer nano-sized agglomerates consisting of Li2Si20s,SiO2,and Si.Through the analysis of the reaction intermediates,molten-UC!could initiate reactions and promote mass transfer by the continuous extraction of oxygen component from SiOx particle inner in the form of inert Li2Si20s and SiO2 nanotubes to realize the.prelithiation.The degree of prelithiation can be regulated by adjusting the coating amount of LiNH2 layer,and the resulted M-Li-SiOx displays a prominent improvement of ICE from 58.73%to 88.2%.The graphite/M-Li-SiOx(8:2)composite electrode delivers a.discharge capacity of 497.29 mAh·g^(-1) with an ICE of 91.79%.By pairing graphite/M-Li-SiOx anode and LiFeP04 cathode in a full-cell an enhancement of energy density of 37.25%is realized compared with the full-cell containing graphite/SiOx anode.Furthermore,,ex-situ X-ray photoelectron spectroscopy(XPS)/Raman/X-ray diffraction(XRD)and related electrochemical measurements reveal the SiOx core and Si of M-Li-SiOx participate in the lithiation,and pre-generated Li2Si20s with u+diffusivity and pomegranate-like.structure reduces the reaction resistance and interface impedance of the solid electrolyte interphase(SEI)film.

Solid-state corrosion of lithium for prelithiation of SiO_(x)-C composite anode with carbon-incorporated lithium phosphorus oxynitride

In order to address the issues of low initial Coulombic efficiency of SiO_(x)-C composite anode due to the formation of solid electrolyte interphase,irreversible conversion reaction,and large volume change,the prelithiation method using metal lithium has been employed as one of effective solutions.However,violent side reactions with liquid electrolyte for prelithiation lead to low prelithiation efficiency and induce poor interface between the SiO_(x)-C electrode and liquid electrolyte.Here,a new prelithiation method with so called solid-state corrosion of lithium is developed.By replacing liquid electrolyte with solid-state electrolyte of carbon-incorporated lithium phosphorus oxynitride(LiCPON),not only various side reactions associated with metal lithium are avoided,but also the perfect interface is achieved from the decomposition products of LiCPON.The successful implementation of solid-state corrosion prelithiation can be confirmed by changes in optical image,scanning electron microscopy,and X-ray diffraction.Compared with pristine electrode,the initial Coulombic efficiency of the prelithiated electrode using solid electrolyte can be increased by about 10%,reaching 98.6%in half cell and 88.9%in full cell.Compared with prelithiated electrode using liquid electrolyte,the prelithiation efficiency of the prelithiated anode with solid-state corrosion can be increased from 25.7%to 82.8%.Solid-state corrosion of lithium is expected to become a useful method for prelithiation of SiO_(x)-C composite electrode with high initial Coulombic efficiency and large prelithiation efficiency.

Mixed ion-electron conducting Li_(3)P for efficient cathode prelithiation of all-solid-state Li-ion batteries

All-solid-state batteries(ASSBs)using sulfide electrolytes hold promise for next-generation battery technology.Although using a pure Li metal anode is believed to maximize battery energy density,numerous recent studies have implicated that Li-ion anodes(e.g.,graphite and Si)are more realistic candidates due to their interfacial compatibility with sulfide electrolytes.However,those Li-ion ASSBs suffer from an issue similar to liquid Li-ion batteries,which is a loss of active Li inventory owing to interfacial side reactions between electrode components,resulting in reduced available capacities and shortened cycle life.Herein,for the first time,we explore the potential of Li_(3)P for cathode prelithiation of Li-ion ASSBs.We identify that the crystallized Li_(3)P(c-Li_(3)P)has room-temperature ionic and electronic conductivities of both over 1o-4 s/cm.Such a mixed ion-electron conduct-ing feature ensures that the neat c-LisP affords a high Li+-releasing capacity of 983 mAh/g in ASSBs during the first charging.Moreover,the electro-chemical delithiation of c-LisP takes place below 2 V versus Li+/Li,while its lithiation dominates below 1 V versus Lit/Li.Once used as a cathode prelithiation regent for ASSBs,c-Li_(3)P only functions as a Li+donor without lithiation activity and can adequately compensate for the Li loss with minimal dosage added.Besides mitigating first-cycle Li loss,c-LisP prelithiation can also improve the battery cyclability by sustained release of low-dosage Li+ions in subsequent cycles,which have been embodied in several full ASSBs by coupling a LiCoO2 cathode with various types of anodes(including graphite,in foil,Sb,and Si anode).Our work provides a universal cathode prelithiation strategy for high-efficiency Li-ion AsSBs.

Innovative Solutions for High-Performance Silicon Anodes in Lithium-Ion Batteries:Overcoming Challenges and Real-World Applications

Silicon(Si)has emerged as a potent anode material for lithium-ion batteries(LIBs),but faces challenges like low electrical conductivity and significant volume changes during lithiation/delithiation,leading to material pulverization and capacity degradation.Recent research on nanostructured Si aims to mitigate volume expansion and enhance electrochemical performance,yet still grapples with issues like pulverization,unstable solid electrolyte interface(SEI)growth,and interparticle resistance.This review delves into innovative strategies for optimizing Si anodes’electrochemical performance via structural engineering,focusing on the synthesis of Si/C composites,engineering multidimensional nanostructures,and applying non-carbonaceous coatings.Forming a stable SEI is vital to prevent electrolyte decomposition and enhance Li^(+)transport,thereby stabilizing the Si anode interface and boosting cycling Coulombic efficiency.We also examine groundbreaking advancements such as self-healing polymers and advanced prelithiation methods to improve initial Coulombic efficiency and combat capacity loss.Our review uniquely provides a detailed examination of these strategies in real-world applications,moving beyond theoretical discussions.It offers a critical analysis of these approaches in terms of performance enhancement,scalability,and commercial feasibility.In conclusion,this review presents a comprehensive view and a forward-looking perspective on designing robust,high-performance Si-based anodes the next generation of LIBs.

Mg-doped,carbon-coated,and prelithiated SiO_(x) as anode materials with improved initial Coulombic efficiency for lithium-ion batteries

Silicon suboxide(SiO_(x),x≈1)is promising in serving as an anode material for lithium-ion batteries with high capacity,but it has a low initial Coulombic efficiency(ICE)due to the irreversible formation of lithium silicates during the first cycle.In this work,we modify SiO_(x) by solid-phase Mg doping reaction using low-cost Mg powder as a reducing agent.We show that Mg reduces SiO_(2) in SiO_(x) to Si and forms MgSiO_(3) or Mg_(2)SiO_(4).The MgSiO_(3) or Mg_(2)SiO_(4) are mainly distributed on the surface of SiO_(x),which suppresses the irreversible lithium-ion loss and enhances the ICE of SiO_(x).However,the formation of MgSiO_(3) or Mg_(2)SiO_(4) also sacrifices the capacity of SiO_(x).Therefore,by controlling the reaction process between Mg and SiO_(x),we can tune the phase composition,proportion,and morphology of the Mg-doped SiO_(x) and manipulate the performance.We obtain samples with a capacity of 1226 mAh g^(–1) and an ICE of 84.12%,which show significant improvement over carbon-coated SiO_(x) without Mg doping.By the synergistical modification of both Mg doping and prelithiation,the capacity of SiO_(x) is further increased to 1477 mAh g^(–1) with a minimal compromise in the ICE(83.77%).

Lithiophilic Li-Si alloy-solid electrolyte interface enabled by high-concentration dual salt-reinforced quasi-solid-state electrolyte

Solid polymer electrolytes(SPEs)are urgently required to achieve practical solid-state lithium metal batteries(LMBs)and lithium-ion batteries(LIBs),Herein,we proposed a mechanism for modulating interfacial conduction and anode interfaces in high-concentration SPEs by LiDFBOP.Optimized electrolyte exhibits superior ionic conductivity and remarkable interface compatibility with salt-rich clusters:(1)polymer-plastic crystal electrolyte(P-PCE,TPU-SN matrix)dissociates ion pairs to facilitate Li+transport in the electrolyte and regulates Li^(+)diffusion in the SEI.The crosslinking structure of the matrix compensates for the loss of mechanical strength at high-salt concentrations;(2)dual-anion TFSI^(-)_(n)-DFBOP^(-)_(m)in the Li^(+)solvation sheath facilitates facile Li^(+)desolvation and formation of salt-rich clusters and is conducive to the formation of Li conductive segments of TPU-SN matrix;(3)theoretical calculations indicate that the decomposition products of LiDFBOP form SEI with lower binding energy with LiF in the SN system,thereby enhancing the interfacial electrochemical redox kinetics of SPE and creating a solid interface SEI layer rich in LiF.As a result,the optimized electrolyte exhibits an excellent ionic conductivity of9.31×10^(-4)S cm^(-1)at 30℃and a broadened electrochemical stability up to 4.73 V.The designed electrolyte effectively prevents the formation of Li dendrites in Li symmetric cells for over 6500 h at0.1 mA cm^(-2).The specific Li-Si alloy-solid state half-cell capacity shows 711.6 mAh g^(-1)after 60 cycles at 0.3 A g^(-1).Excellent rate performance and cycling stability are achieved for these solid-state batteries with Li-Si alloy anodes and NCM 811 cathodes.NCM 811‖Prelithiated silicon-based anode solid-state cell delivers a discharge capacity of 195.55 mAh g^(-1)and a capacity retention of 97.8%after 120 cycles.NCM 811‖Li solid-state cell also delivers capacity retention of 84.2%after 450 cycles.