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...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.展开更多
Free-standing silicon anodes with high proportion of active materials have aroused great attention;however,the mechanical stability and electrochemical performance are severely suppressed.Herein,to resolve the appeal ...Free-standing silicon anodes with high proportion of active materials have aroused great attention;however,the mechanical stability and electrochemical performance are severely suppressed.Herein,to resolve the appeal issues,a free-standing anode with a"corrugated paper"shape on micro-scale and a topological crosslinking network on the submicron and nano-scale is designed.Essentially,an integrated three-dimensional electrode structure is constructed based on robust carbon nanotubes network with firmly anchored SiNPs via forming interlocking junctions.In which,the hierarchical interlocking structure is achieved by directional induction of the binder,which ensures well integration during cycling so that significantly enhances mechanical stability as well as electronic and ionic conductivity of electrodes.Benefiting from it,this anode exhibits outsta nding performance under harsh service conditions including high Si loading,ultrahigh areal capacity(33.2 mA h cm^(-2)),and high/low temperatures(-15-60℃),which significantly extends its practical prospect.Furthermore,the optimization mechanism of this electrode is explored to verify the crack-healing and structure-integration maintaining along cycling via a unique self-stabilization process.Thus,from both the fundamental and engineering views,this strategy offers a promising path to produce high-performance free-standing electrodes for flexible device applications especially facing volume effect challenges.展开更多
Silicon(Si)is a competitive anode material owing to its high theoretical capacity and low electrochemical potential.Recently,the prospect of Si anodes in solid-state batteries(SSBs)has been proposed due to less solid ...Silicon(Si)is a competitive anode material owing to its high theoretical capacity and low electrochemical potential.Recently,the prospect of Si anodes in solid-state batteries(SSBs)has been proposed due to less solid electrolyte interphase(SEI)formation and particle pulverization.However,major challenges arise for Si anodes in SSBs at elevated temperatures.In this work,the failure mechanisms of Si-Li_(6)PS_(5)Cl(LPSC)composite anodes above 80℃are thoroughly investigated from the perspectives of interface stability and(electro)chemo-mechanical effect.The chemistry and growth kinetics of Lix Si|LPSC interphase are demonstrated by combining electrochemical,chemical and computational characterizations.Si and/or Si–P compound formed at Lix Si|LPSC interface prove to be detrimental to interface stability at high temperatures.On the other hand,excessive volume expansion and local stress caused by Si lithiation at high temperatures damage the mechanical structure of Si-LPSC composite anodes.This work elucidates the behavior and failure mechanisms of Si-based anodes in SSBs at high temperatures and provides insights into upgrading Si-based anodes for application in SSBs.展开更多
The extreme volume expansion of the silicon(Si) anodes during repeated cycles seriously induces undesirable interfacial side reactions,forming an unstable solid electrolyte interphase(SEI) that degrades the electrode ...The extreme volume expansion of the silicon(Si) anodes during repeated cycles seriously induces undesirable interfacial side reactions,forming an unstable solid electrolyte interphase(SEI) that degrades the electrode integrity and cycle stability in lithium-ion batteries,limiting their practical applications.Despite considerable efforts to stabilize the SEI through surface modification,challenges persist in the development of high-performance Si anodes that effectively regulate intrinsic SEI properties and simultaneously facilitate electron/ion transport.Here,a highly conductive and organic electrolyte-compatible lamellar p-toluenesulfonic acid-doped polyaniline(pTAP) layer is proposed for constructing a robust artificial SEI on Si nanoparticles to achieve fast charging,lo ng-term cycle lifespan and high areal capacity.The spatially uniform pTAP layer,formed through a facile direct-encapsulation approach assisted by enriched hydrogen bonding,contributes to the effective formation of in situ SEI with an even distribution of the LiF-rich phase in its interlamination spaces.Furthermore,the integrated artificial SEI facilitates isotropic ion/electron transport,increased robustness,and effectively dissipates stress from volume changes.Consequently,a notably high rate performance of 570 mA h g^(-1),even at a substantially high current density of 10 A g^(-1),is achieved with excellent cyclic stability by showing a superior capacity over 1430 mA h g^(-1) at 1 A g^(-1) after 250 cycles and a high areal capacity of ca.2 mA h cm^(-2) at 0.5 C in a full cell system.This study demonstrates that the rational design of conductive polymers with SEI modulation for surface protection has great potential for use in high-energy-density Si anodes.展开更多
In the development of rechargeable lithium ion batteries(LIBs),silicon anodes have attracted much attention because of their extremely high theoretical capacity,relatively low Li-insertion voltage and the availability...In the development of rechargeable lithium ion batteries(LIBs),silicon anodes have attracted much attention because of their extremely high theoretical capacity,relatively low Li-insertion voltage and the availability of silicon resources.However,their large volume expansion and fragile solid electrolyte interface(SEI)film hinder their commercial application.To solve these problems,Si has been combined with various carbon materials to increase their structural stability and improve their interface properties.The use of different carbon materials,such as amorphous carbon and graphite,as three-dimensional(3D)protective anode coatings that help buffer mechanical strain and isolate the electrolyte is detailed,and novel methods for applying the coatings are outlined.However,carbon materials used as a protective layer still have some disadvantages,necessitating their modification.Recent developments have focused on modifying the protective carbon shells,and substitutes for the carbon have been suggested.展开更多
Binders could play crucial or even decisive roles in the fabrication of low-cost, stable and high-capacity electrodes. This is especially the case for the silicon (Si) anodes and sulfur (S) cathodes that undergo large...Binders could play crucial or even decisive roles in the fabrication of low-cost, stable and high-capacity electrodes. This is especially the case for the silicon (Si) anodes and sulfur (S) cathodes that undergo large volume change and active material loss in lithium-ion batteries during prolonged cycles. Herein, a hydrophilic polymer poly(methyl vinyl ether-alt-maleic acid) (PMVEMA) was explored as a dual-functional aqueous binder for the preparation of high-performance silicon anode and sulfur cathode. Benefiting from the dual functions of PMVEMA, i.e., the excellent dispersion ability and strong binding forces, the as-prepared electrodes exhibit improved capacity, rate capability and long-term cycling performance. In particular, the as-prepared Si electrode delivers a high initial discharge capacity of 1346.5 mAh g^(−1) at a high rate of 8.4 A/g and maintains 834.5 mAh g^(−1) after 300 cycles at 4.2 A/g, while the as-prepared S cathode exhibits enhanced cycling performance with high remaining discharge capacities of 663.4 mAh g^(−1) after 100 cycles at 0.2 C and 487.07 mAh g^(−1) after 300 cycles at 1 C, respectively. These encouraging results suggest that PMVEMA could be a universal binder to facilitate the green manufacture of both anode and cathode for high-capacity energy storage systems.展开更多
Silicon-based(Si)materials are promising anodes for lithium-ion batteries(LIBs)because of their ultrahigh theoretical capacity of 4200 mA h g^(−1).However,commercial applications of Si anodes have been hindered by the...Silicon-based(Si)materials are promising anodes for lithium-ion batteries(LIBs)because of their ultrahigh theoretical capacity of 4200 mA h g^(−1).However,commercial applications of Si anodes have been hindered by their drastic volume variation(∼300%)and low electrical conductivity.Here,to tackle the drawbacks,a hierarchical Si anode with double-layer coatings of a SiOx inner layer and a nitrogen(N),boron(B)co-doped carbon(C-NB)outer layer is elaborately designed by copyrolysis of Si-OH structures and a H3BO_(3)-doped polyaniline polymer on the Si surface.Compared with the pristine Si anodes(7mA h g^(−1) at 0.5 A g^(−1) after 340 cycles and 340 mA h g^(−1) at 5 A g^(−1)),the modified Si-based materials(Si@SiOx@C-NB nanospheres)present su perior cycling stability(reversible 1301 mA h g^(−1) at 0.5 A g^(−1) after 340 cycles)as well as excellent rate capability(690mA h g^(−1) at 5 A g^(−1))when used as anodes in LIBs.The unique double-layer coating structure,in which the inner amorphous SiOx layer acts as a buffer matrix and the outer defect-rich carbon enhances the electron diffusion of the whole anode,makes it possible to de liver excellent electrochemical properties.These results indicate that our double-layer coating strategy is a promising approach not only for the devel opment of sustainable Si anodes but also for the design of multielement-doped carbon nanomaterials.展开更多
Since the volume variation of silicon particles during cycling,the binding spots between Cu current collector and silicon anode raised to be one of the critical binding problems.In this work,an amino-modified Cu curre...Since the volume variation of silicon particles during cycling,the binding spots between Cu current collector and silicon anode raised to be one of the critical binding problems.In this work,an amino-modified Cu current collector(Cu^(*))is fabricated to tackle this issue.The amino groups on Cu^(*)surface increase its hydrophilicity,which is conducive to the curing process of aqueous slurry on its surface.Meanwhile,these amino groups can form abundant amide bonds with carboxyl groups from the adopted polyacrylic acid(PAA)binder.The combined action composed of the covalent bond and mechanical interlocking could reduce the contact loss inside the electrode.However,high concentration silane coupling agent treatment will weaken the surface roughness of Cu^(*)and weaken mechanical interlocking.What is more,the insulation of silane coupling agent reduces the conductivity of Cu and increases the impedance of battery.Considering the effect of silane coupling agent comprehensively,electrochemical performance of Cu^(*)-0.05%is best.展开更多
We report the synthesis of a high‐performance graphitic carbon‐coated silicon(Si@GC)composite material for lithium‐ion batteries via a scalable production route.Porous Si is produced from the magnesiothermic reduct...We report the synthesis of a high‐performance graphitic carbon‐coated silicon(Si@GC)composite material for lithium‐ion batteries via a scalable production route.Porous Si is produced from the magnesiothermic reduction of commercial silica(SiO2)precursor followed by low‐temperature graphitic carbon coating using glucose as the precursor.The obtained Si@GC composite achieves an excellent reversible specific capacity of 1195 mAh g−1 and outstanding cycle stability.The thick Si@GC anode(3.4 mg cm^−2)in full cells with commercial lithium iron phosphate cathode delivers a remarkable performance of 800 mAh g^−1 specific capacity and 2.7 mAh cm^−2 areal capacity as well as 93.6%capacity retention after 200 cycles.展开更多
Silicon(Si)has been investigated as a promising anode material because of its high theoretical capacity(4200 m Ah g^(-1)).However,silicon anode suffers from huge volume changes during repeated charge–discharge cycles...Silicon(Si)has been investigated as a promising anode material because of its high theoretical capacity(4200 m Ah g^(-1)).However,silicon anode suffers from huge volume changes during repeated charge–discharge cycles.In this work,inspired by a remarkable success of the glutinous rice mortar in the Great Wall with ca.2000-year history,amylopectin(AP),the key ingredient responsible for the strong bonding force,is extracted from glutinous rice and utilized as a flexible,aqueous,and resilient binder to address the most challenging drastic volume-expansion and pulverization issues of silicon anode.Additionally,the removal of toxic N-methyl-2-pyrrolidone(NMP)organic solvent makes the electrode fabrication process environmentally friendly and healthy.The as-prepared Si-AP electrode with 60 wt%of Si can uphold a high discharge capacity of 1517.9 m Ah g^(-1)at a rate of 0.1 C after 100 cycles.The cycling stability of the Si-AP has been remarkably improved in comparison with both traditional polyvinylidene fluoride(PVDF)and aqueous carboxymethylcellulose(CMC)binders.Moreover,when the content of silicon in the Si-AP electrode increases to 70 wt%,a high discharge capacity of 1463.1 m Ah g^(-1)can still be obtained after 50 cycles at 0.1°C.These preliminary results suggest that the sustainably available and environmentally benign amylopectin binders could be a promising choice for the construction of highly stable silicon anodes.展开更多
Silicon has ultrahigh capacity,dendrite-free alloy lithiation mechanism and low cost and has been regarded as a promising anode candidate for solid-state battery.Owing to the low infiltration of solid-state electrolyt...Silicon has ultrahigh capacity,dendrite-free alloy lithiation mechanism and low cost and has been regarded as a promising anode candidate for solid-state battery.Owing to the low infiltration of solid-state electrolyte(SSE),not the unstable solid-electrolyte interphase(SEI),but the huge stress during lithiation-and delithiation-induced particle fracture and conductivity lost tend to be the main issues.In this study,starting with micron-Si,a novel monothetic carbon conductive framework and a MgO coating layer are designed,which serve as electron pathway across the whole electrode and stress releasing layer,respectively.In addition,the in situ reaction between Si and SSE helps to form a LiF-rich and mechanically stable SEI layer.As a result,the mechanical stability and charge transfer kinetics of the uniquely designed Si anode are significantly improved.Consequently,high initial Coulombic efficiency,high capacity and durable cycling stability can be achieved by applying the Si@MgO@C anode in SSB.For example,high specific capacity of 3224.6 mAh·g^(-1)and long cycling durability of 200 cycles are achieved.This work provides a new concept for designing alloy-type anode that combines surface coating on particle and electrode structure design.展开更多
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.Her...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.展开更多
Recent technological advancements,such as portable electronics and electric vehicles,have created a pressing need for more efficient energy storage solutions.Lithium-ion batteries(LIBs)have been the preferred choice f...Recent technological advancements,such as portable electronics and electric vehicles,have created a pressing need for more efficient energy storage solutions.Lithium-ion batteries(LIBs)have been the preferred choice for these applications,with graphite being the standard anode material due to its stability.However,graphite falls short of meeting the growing demand for higher energy density,possessing a theoretical capacity that lags behind.To address this,researchers are actively seeking alternative materials to replace graphite in commercial batteries.One promising avenue involves lithiumalloying materials like silicon and phosphorus,which offer high theoretical capacities.Carbon-silicon composites have emerged as a viable option,showing improved capacity and performance over traditional graphite or pure silicon anodes.Yet,the existing methods for synthesizing these composites remain complex,energy-intensive,and costly,preventing widespread adoption.A groundbreaking approach is presented here:the use of a laser writing strategy to rapidly transform common organic carbon precursors and silicon blends into efficient“graphenic silicon”composite thin films.These films exhibit exceptional structural and energy storage properties.The resulting three-dimensional porous composite anodes showcase impressive attributes,including ultrahigh silicon content,remarkable cyclic stability(over 4500 cycles with∼40%retention),rapid charging rates(up to 10 A g^(-1)),substantial areal capacity(>5.1 mAh cm^(-2)),and excellent gravimetric capacity(>2400 mAh g^(-1) at 0.2 A g^(-1)).This strategy marks a significant step toward the scalable production of high-performance LIB materials.Leveraging widely available,cost-effective precursors,the laser-printed“graphenic silicon”composites demonstrate unparalleled performance,potentially streamlining anode production while maintaining exceptional capabilities.This innovation not only paves the way for advanced LIBs but also sets a precedent for transforming various materials into high-performing electrodes,promising reduced complexity and cost in battery production.展开更多
Increasing the density and thickness of electrodes is required to maximize the volumetric energy density of lithium-ion batteries for practical applications.However,dense and thick electrodes,especially highmass-conte...Increasing the density and thickness of electrodes is required to maximize the volumetric energy density of lithium-ion batteries for practical applications.However,dense and thick electrodes,especially highmass-content(>50 wt%) silicon anodes,have poor mechanical stability due to the presence of a large number of unstable interfaces between the silicon and conducting components during cycling.Here we report a network of mechanically robust carbon cages produced by the capillary shrinkage of graphene hydrogels that can contain the silicon nanoparticles in the cages and stabilize the silicon/carbon interfaces.In situ transmission electron microscope characterizations including compression and tearing of the structure and lithiation-induced silicon expansion experiments,have provided insight into the excellent confinement and buffering ability of this interface-strengthened graphene-caged silicon nanoparticle anode material.Consequently,a dense and thick silicon anode with reduced thickness fluctuations has been shown to deliver both high volumetric(>1000 mAh cm^-3) and areal(>6 mAh cm^-2)capacities together with excellent cycling capability.展开更多
Silicon anodes have drawn ever-increasing attention in lithium-ion batteries(LIBs) owing to their extremely high theoretical capacity and abundance in the earth. Despite promising advantages, the wide use of silicon a...Silicon anodes have drawn ever-increasing attention in lithium-ion batteries(LIBs) owing to their extremely high theoretical capacity and abundance in the earth. Despite promising advantages, the wide use of silicon anodes in LIBs is highly hindered by their fast capacity fading and low Coulombic efficiency arising from their substantial volumetric variation(>300%). Herein, we report a novel aqueous hybrid gel binder for silicon anodes via crosslinking sodium carboxymethyl cellulose(NaCMC) by an inorganic crosslinker-sodium borate. Not only this gel polymer binder can chemically bond to silicon nanoparticle, but also the deformable framework of this crosslinked binder is capable of maintaining electrode integrity, thus buffering dramatic volume change of silicon. Consequently, the silicon anode with this gel binder exhibits good cycle life(1211.5 mAh/g after 600 cycles) and high initial Coulombic efficiency(88.95%).展开更多
Silicon (Si) is a promising anode material for next-generation high-energy lithium-ion batteries (LIBs) due to its high capacity.However,the large volumetric expansion,poor ion conductivity and unstable solid electrol...Silicon (Si) is a promising anode material for next-generation high-energy lithium-ion batteries (LIBs) due to its high capacity.However,the large volumetric expansion,poor ion conductivity and unstable solid electrolyte interface (SEI) lead to rapid capacity fading and low rate performance.Herein,we report Si nitride (SiN) comprising stoichiometric Si_(3)N_(4) and Li-active anazotic SiN_(x) coated porous Si (p-Si@SiN)for high-performance anodes in LIBs.The ant-nest-like porous Si consisting of 3D interconnected Si nanoligaments and bicontinuous nanopores prevents pulverization and accommodates volume expansion during cycling.The Si_(3)N_(4) offers mechanically protective coating to endow highly structural integrity and inhibit superfluous formation of SEI.The fast ion conducting Li_(3)N generated in situ from lithiation of active SiN_(x) facilitates Li ion transport.Consequently,the p-Si@SiN anode has appealing electrochemical properties such as a high capacity of 2180 mAh g^(-1)at 0.5 A g^(-1) with 84%capacity retention after 200cycles and excellent rate capacity with discharge capacity of 721 mAh g^(-1) after 500 cycles at 5.0 A g^(-1).This work provides insights into the rational design of active/inactive nanocoating on Si-based anode materials for fast-charging and highly stable LIBs.展开更多
Lithium-ion battery anode used as silicon particles were obtained from different major suppliers,and they were characterized by different spectroscopic techniques and evaluated by electrochemical experiments.Correlati...Lithium-ion battery anode used as silicon particles were obtained from different major suppliers,and they were characterized by different spectroscopic techniques and evaluated by electrochemical experiments.Correlations between the key physical parameters and electrochemical properties of the silicon particles were investigated.Silicon particle size,surface oxygen content,-OH content and physical appearance are found to strongly influence the electrochemical properties of the Si anode.The particle size of 100 nm has great promise for the practical application of Si nanoparticles in the lithium-ion battery industry.An inverse correlation between the oxygen content and the reversible capacity or first coulombic efficiency was obtained.The-OH content by surface treatment contributes to enhanced cycling stability by the improved affinity between the Si particle and the water-soluble binder.Spherical Si particles perform better compared to irregular particles,and agglomeration dramatically decreases the cycling stability of the Si anode.Among the investigated Si particles,the sample that exhibited a reversible capacity of more than 2500 mAh g^(-1),a first coulombic efficiency of 89.26%and an excellent cycling stability,has great potential for use in the battery industry.展开更多
Si is a promising anode material for Li ion batteries because of its high specific capacity,abundant reserve,and low cost.However,its rate performance and cycling stability are poor due to the severe particle pulveriz...Si is a promising anode material for Li ion batteries because of its high specific capacity,abundant reserve,and low cost.However,its rate performance and cycling stability are poor due to the severe particle pulverization during the lithiation/delithiation process.The high stress induced by the Li concentration gradient and anisotropic deformation is the main reason for the fracture of Si particles.Here we present a new stress mitigation strategy by uniformly distributing small amounts of Sn and Sb in Si micron-sized particles,which reduces the Li concentration gradient and realizes an isotropic lithiation/delithiation process.The Si8.5Sn0.5Sb microparticles(mean particle size:8.22μm)show over 6000-fold and tenfold improvements in electronic conductivity and Li diffusivity than Si particles,respectively.The discharge capacities of the Si_(8.5)Sn_(0.5)Sb microparticle anode after 100 cycles at 1.0 and 3.0 A g^(-1)are 1.62 and 1.19 Ah g^(-1),respectively,corresponding to a retention rate of 94.2%and 99.6%,respectively,relative to the capacity of the first cycle after activation.Multicomponent microparticle anodes containing Si,Sn,Sb,Ge and Ag prepared using the same method yields an ultra-low capacity decay rate of 0.02%per cycle for 1000 cycles at 1 A g^(-1),corroborating the proposed mechanism.The stress regulation mechanism enabled by the industry-compatible fabrication methods opens up enormous opportunities for low-cost and high-energy-density Li-ion batteries.展开更多
Sulfide solid electrolyte(SE)is one of the most promising technologies for all-solid-state batteries(ASSBs)because of its high ionic conductivity and ductile mechanical properties.In order to further improve the energ...Sulfide solid electrolyte(SE)is one of the most promising technologies for all-solid-state batteries(ASSBs)because of its high ionic conductivity and ductile mechanical properties.In order to further improve the energy density of sulfide-based ASSBs and promote practical applications,silicon anodes with ultrahigh theoretical capacity(4,200 mAh·g^(−1))and rich resource abundance have broad commercial prospects.However,significant challenges including bulk instability of sulfide SEs and poor utilization of silicon materials have severely impeded the ASSBs from becoming viable.In this review,we first introduce the critical bulk properties of sulfide SEs and the most recent improving strategies covering the ionic conductivity,air stability,electrochemical window,mechanical stability,thermostability and solvent stability.Next,we introduce the main factors affecting the compatibility of silicon and sulfide SE,including the carbon’s effect,particle size of silicon,external pressure,silicon composite matrix and the depth of silicon’s lithiation.Finally,we discuss possible research directions in the future.We hope that this review can provide a comprehensive picture of the role of nanoscale approaches in recent advances in ASSBs with sulfide and silicon,as well as a source of inspiration for future research.展开更多
Nowadays,silicon has become a promising anode active material for lithium-ion batteries due to its high specific capacity.However,traditional binder materials cannot effectively restrain the volume expansion of silico...Nowadays,silicon has become a promising anode active material for lithium-ion batteries due to its high specific capacity.However,traditional binder materials cannot effectively restrain the volume expansion of silicon during lithiation/delithiation.Inspired by the growth process of climbing plants,we sequentially crosslink sodium alginate with calcium ions and hyperbranched polyethyleneimine to construct a dual crosslinked network binder.During the sequentially crosslinking,sodium alginate preferentially crosslinks with Ca^(2+)to form the"trellis"network,which restricts the free movement of hyperbranched polyethyleneimine and guides it,like"vine",to gradually anchor on the surrounding"trellis"through hydrogen and ionic bonding.In this dual crosslinked network,the ionic ally crosslinked sodium alginate maintains the anode structural integrity;the anchored hyperbranched polyethyleneimine forms strong multidimensional hydrogen bonds with silicon nanoparticles through its amino-rich branch chains;and the network utilizes the bonding reversibility of hydrogen and ionic bonds to repeatedly eliminate the mechanical stress and self-heal the structure damages caused by the volume change of silicon.Benefited from the multifunction of the dual crosslinked network,the silicon anode has achieved an excellent electrochemical performance with a specific capacity of 2403 mAh·g^(-1)at the current density of500 mA·g^(-1)after 100 cycles.展开更多
基金financially supported by the Jiangsu Distinguished Professors Project(No.1711510024)the funding for Scientific Research Startup of Jiangsu University(Nos.4111510015,19JDG044)+3 种基金the Jiangsu Provincial Program for High-Level Innovative and Entrepreneurial Talents Introductionthe National Natural Science Foundation of China(No.22008091)Natural Science Foundation of Guangdong Province(2023A1515010894)the Open Project of Luzhou Key Laboratory of Fine Chemical Application Technology(HYJH-2302-A).
文摘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.
基金sponsored by the National Natural Science Foundation of China(21905221,21805221)the Suzhou Technological innovation of key industries-research and development of key technologies(SGC2021118)。
文摘Free-standing silicon anodes with high proportion of active materials have aroused great attention;however,the mechanical stability and electrochemical performance are severely suppressed.Herein,to resolve the appeal issues,a free-standing anode with a"corrugated paper"shape on micro-scale and a topological crosslinking network on the submicron and nano-scale is designed.Essentially,an integrated three-dimensional electrode structure is constructed based on robust carbon nanotubes network with firmly anchored SiNPs via forming interlocking junctions.In which,the hierarchical interlocking structure is achieved by directional induction of the binder,which ensures well integration during cycling so that significantly enhances mechanical stability as well as electronic and ionic conductivity of electrodes.Benefiting from it,this anode exhibits outsta nding performance under harsh service conditions including high Si loading,ultrahigh areal capacity(33.2 mA h cm^(-2)),and high/low temperatures(-15-60℃),which significantly extends its practical prospect.Furthermore,the optimization mechanism of this electrode is explored to verify the crack-healing and structure-integration maintaining along cycling via a unique self-stabilization process.Thus,from both the fundamental and engineering views,this strategy offers a promising path to produce high-performance free-standing electrodes for flexible device applications especially facing volume effect challenges.
基金Project supported by the Major Program of the National Natural Science Foundation of China (Grant No.22393904)the National Key Research and Development Program of China (Grant No.2022YFB2502200)+1 种基金Beijing Municipal Science&Technology Commission (Grant No.Z221100006722015)the New Energy Vehicle Power Battery Life Cycle Testing and Verification Public Service Platform Project (Grant No.2022-235-224)。
文摘Silicon(Si)is a competitive anode material owing to its high theoretical capacity and low electrochemical potential.Recently,the prospect of Si anodes in solid-state batteries(SSBs)has been proposed due to less solid electrolyte interphase(SEI)formation and particle pulverization.However,major challenges arise for Si anodes in SSBs at elevated temperatures.In this work,the failure mechanisms of Si-Li_(6)PS_(5)Cl(LPSC)composite anodes above 80℃are thoroughly investigated from the perspectives of interface stability and(electro)chemo-mechanical effect.The chemistry and growth kinetics of Lix Si|LPSC interphase are demonstrated by combining electrochemical,chemical and computational characterizations.Si and/or Si–P compound formed at Lix Si|LPSC interface prove to be detrimental to interface stability at high temperatures.On the other hand,excessive volume expansion and local stress caused by Si lithiation at high temperatures damage the mechanical structure of Si-LPSC composite anodes.This work elucidates the behavior and failure mechanisms of Si-based anodes in SSBs at high temperatures and provides insights into upgrading Si-based anodes for application in SSBs.
基金National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) [NRF-2021R1A5A1084921]the “Human Resources Program in Energy Technology” of the Korea Institute of Energy Technology Evaluation and Planning (KETEP), granted financial resource from the Ministry of Trade, Industry & Energy, Republic of Korea [No. 20204010600100]the Materials and Components Technology Development Program of the Ministry of Trade, Industry and Energy (MOTIE, Korea) and Korea Electronics Technology Institute (KETI) [20012224]。
文摘The extreme volume expansion of the silicon(Si) anodes during repeated cycles seriously induces undesirable interfacial side reactions,forming an unstable solid electrolyte interphase(SEI) that degrades the electrode integrity and cycle stability in lithium-ion batteries,limiting their practical applications.Despite considerable efforts to stabilize the SEI through surface modification,challenges persist in the development of high-performance Si anodes that effectively regulate intrinsic SEI properties and simultaneously facilitate electron/ion transport.Here,a highly conductive and organic electrolyte-compatible lamellar p-toluenesulfonic acid-doped polyaniline(pTAP) layer is proposed for constructing a robust artificial SEI on Si nanoparticles to achieve fast charging,lo ng-term cycle lifespan and high areal capacity.The spatially uniform pTAP layer,formed through a facile direct-encapsulation approach assisted by enriched hydrogen bonding,contributes to the effective formation of in situ SEI with an even distribution of the LiF-rich phase in its interlamination spaces.Furthermore,the integrated artificial SEI facilitates isotropic ion/electron transport,increased robustness,and effectively dissipates stress from volume changes.Consequently,a notably high rate performance of 570 mA h g^(-1),even at a substantially high current density of 10 A g^(-1),is achieved with excellent cyclic stability by showing a superior capacity over 1430 mA h g^(-1) at 1 A g^(-1) after 250 cycles and a high areal capacity of ca.2 mA h cm^(-2) at 0.5 C in a full cell system.This study demonstrates that the rational design of conductive polymers with SEI modulation for surface protection has great potential for use in high-energy-density Si anodes.
文摘In the development of rechargeable lithium ion batteries(LIBs),silicon anodes have attracted much attention because of their extremely high theoretical capacity,relatively low Li-insertion voltage and the availability of silicon resources.However,their large volume expansion and fragile solid electrolyte interface(SEI)film hinder their commercial application.To solve these problems,Si has been combined with various carbon materials to increase their structural stability and improve their interface properties.The use of different carbon materials,such as amorphous carbon and graphite,as three-dimensional(3D)protective anode coatings that help buffer mechanical strain and isolate the electrolyte is detailed,and novel methods for applying the coatings are outlined.However,carbon materials used as a protective layer still have some disadvantages,necessitating their modification.Recent developments have focused on modifying the protective carbon shells,and substitutes for the carbon have been suggested.
基金This work was financially supported by the Australian Research Council(ARC)Discovery Projects(DP210103266 and DPI 701048343)the Griffith University Ph.D.Scholarships.
文摘Binders could play crucial or even decisive roles in the fabrication of low-cost, stable and high-capacity electrodes. This is especially the case for the silicon (Si) anodes and sulfur (S) cathodes that undergo large volume change and active material loss in lithium-ion batteries during prolonged cycles. Herein, a hydrophilic polymer poly(methyl vinyl ether-alt-maleic acid) (PMVEMA) was explored as a dual-functional aqueous binder for the preparation of high-performance silicon anode and sulfur cathode. Benefiting from the dual functions of PMVEMA, i.e., the excellent dispersion ability and strong binding forces, the as-prepared electrodes exhibit improved capacity, rate capability and long-term cycling performance. In particular, the as-prepared Si electrode delivers a high initial discharge capacity of 1346.5 mAh g^(−1) at a high rate of 8.4 A/g and maintains 834.5 mAh g^(−1) after 300 cycles at 4.2 A/g, while the as-prepared S cathode exhibits enhanced cycling performance with high remaining discharge capacities of 663.4 mAh g^(−1) after 100 cycles at 0.2 C and 487.07 mAh g^(−1) after 300 cycles at 1 C, respectively. These encouraging results suggest that PMVEMA could be a universal binder to facilitate the green manufacture of both anode and cathode for high-capacity energy storage systems.
基金supported by Joint Funds of the National Natural Science Foundation of China(U20A20280)the National Natural Science Foundation of China(21805083,52074119)+3 种基金the Academy of Sciences large apparatus United Fund of China(U1832187)the Scientific Research Fund of Hunan Provincial Education Department(19K058)the Science and Technology Planning Project of Hunan Province(2018TP1017)the High-Tech Leading Plan of Hunan Province(2020GK2072).
文摘Silicon-based(Si)materials are promising anodes for lithium-ion batteries(LIBs)because of their ultrahigh theoretical capacity of 4200 mA h g^(−1).However,commercial applications of Si anodes have been hindered by their drastic volume variation(∼300%)and low electrical conductivity.Here,to tackle the drawbacks,a hierarchical Si anode with double-layer coatings of a SiOx inner layer and a nitrogen(N),boron(B)co-doped carbon(C-NB)outer layer is elaborately designed by copyrolysis of Si-OH structures and a H3BO_(3)-doped polyaniline polymer on the Si surface.Compared with the pristine Si anodes(7mA h g^(−1) at 0.5 A g^(−1) after 340 cycles and 340 mA h g^(−1) at 5 A g^(−1)),the modified Si-based materials(Si@SiOx@C-NB nanospheres)present su perior cycling stability(reversible 1301 mA h g^(−1) at 0.5 A g^(−1) after 340 cycles)as well as excellent rate capability(690mA h g^(−1) at 5 A g^(−1))when used as anodes in LIBs.The unique double-layer coating structure,in which the inner amorphous SiOx layer acts as a buffer matrix and the outer defect-rich carbon enhances the electron diffusion of the whole anode,makes it possible to de liver excellent electrochemical properties.These results indicate that our double-layer coating strategy is a promising approach not only for the devel opment of sustainable Si anodes but also for the design of multielement-doped carbon nanomaterials.
基金Project(2019R01006)supported by the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang Province,ChinaProject(2018YFB0104300)supported by the National Key R&D Program of China。
文摘Since the volume variation of silicon particles during cycling,the binding spots between Cu current collector and silicon anode raised to be one of the critical binding problems.In this work,an amino-modified Cu current collector(Cu^(*))is fabricated to tackle this issue.The amino groups on Cu^(*)surface increase its hydrophilicity,which is conducive to the curing process of aqueous slurry on its surface.Meanwhile,these amino groups can form abundant amide bonds with carboxyl groups from the adopted polyacrylic acid(PAA)binder.The combined action composed of the covalent bond and mechanical interlocking could reduce the contact loss inside the electrode.However,high concentration silane coupling agent treatment will weaken the surface roughness of Cu^(*)and weaken mechanical interlocking.What is more,the insulation of silane coupling agent reduces the conductivity of Cu and increases the impedance of battery.Considering the effect of silane coupling agent comprehensively,electrochemical performance of Cu^(*)-0.05%is best.
文摘We report the synthesis of a high‐performance graphitic carbon‐coated silicon(Si@GC)composite material for lithium‐ion batteries via a scalable production route.Porous Si is produced from the magnesiothermic reduction of commercial silica(SiO2)precursor followed by low‐temperature graphitic carbon coating using glucose as the precursor.The obtained Si@GC composite achieves an excellent reversible specific capacity of 1195 mAh g−1 and outstanding cycle stability.The thick Si@GC anode(3.4 mg cm^−2)in full cells with commercial lithium iron phosphate cathode delivers a remarkable performance of 800 mAh g^−1 specific capacity and 2.7 mAh cm^−2 areal capacity as well as 93.6%capacity retention after 200 cycles.
基金financial support from the Australia Research Council Discovery Projects(DP160102627 and DP1701048343)of Australiathe 111 Project(D20015)of China Three Gorges University
文摘Silicon(Si)has been investigated as a promising anode material because of its high theoretical capacity(4200 m Ah g^(-1)).However,silicon anode suffers from huge volume changes during repeated charge–discharge cycles.In this work,inspired by a remarkable success of the glutinous rice mortar in the Great Wall with ca.2000-year history,amylopectin(AP),the key ingredient responsible for the strong bonding force,is extracted from glutinous rice and utilized as a flexible,aqueous,and resilient binder to address the most challenging drastic volume-expansion and pulverization issues of silicon anode.Additionally,the removal of toxic N-methyl-2-pyrrolidone(NMP)organic solvent makes the electrode fabrication process environmentally friendly and healthy.The as-prepared Si-AP electrode with 60 wt%of Si can uphold a high discharge capacity of 1517.9 m Ah g^(-1)at a rate of 0.1 C after 100 cycles.The cycling stability of the Si-AP has been remarkably improved in comparison with both traditional polyvinylidene fluoride(PVDF)and aqueous carboxymethylcellulose(CMC)binders.Moreover,when the content of silicon in the Si-AP electrode increases to 70 wt%,a high discharge capacity of 1463.1 m Ah g^(-1)can still be obtained after 50 cycles at 0.1°C.These preliminary results suggest that the sustainably available and environmentally benign amylopectin binders could be a promising choice for the construction of highly stable silicon anodes.
基金financially supported by the National Natural Science Foundation of China(No.22209075)the Natural Science Foundation of Jiangsu Province(BK20200800)。
文摘Silicon has ultrahigh capacity,dendrite-free alloy lithiation mechanism and low cost and has been regarded as a promising anode candidate for solid-state battery.Owing to the low infiltration of solid-state electrolyte(SSE),not the unstable solid-electrolyte interphase(SEI),but the huge stress during lithiation-and delithiation-induced particle fracture and conductivity lost tend to be the main issues.In this study,starting with micron-Si,a novel monothetic carbon conductive framework and a MgO coating layer are designed,which serve as electron pathway across the whole electrode and stress releasing layer,respectively.In addition,the in situ reaction between Si and SSE helps to form a LiF-rich and mechanically stable SEI layer.As a result,the mechanical stability and charge transfer kinetics of the uniquely designed Si anode are significantly improved.Consequently,high initial Coulombic efficiency,high capacity and durable cycling stability can be achieved by applying the Si@MgO@C anode in SSB.For example,high specific capacity of 3224.6 mAh·g^(-1)and long cycling durability of 200 cycles are achieved.This work provides a new concept for designing alloy-type anode that combines surface coating on particle and electrode structure design.
基金National Natural Science Foundation of China,Grant/Award Number:22179006Natural Science Foundation of Zhejiang Province,Grant/Award Number:LQ23E020002+4 种基金National Natural Science Foundation of China,Grant/Award Numbers:52202284,52072036Cooperation between Industry and Education Project of Ministry of Education,Grant/Award Number:220601318235513WenZhou Natural Science Foundation,Grant/Award Numbers:G20220019,G20220021State Key Laboratory of Electrical Insulation and Power Equipment,Xi'an Jiaotong University,Grant/Award Number:EIPE22208Key Research and Development Program of Henan province,China,Grant/Award Number:231111242500。
文摘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.
文摘Recent technological advancements,such as portable electronics and electric vehicles,have created a pressing need for more efficient energy storage solutions.Lithium-ion batteries(LIBs)have been the preferred choice for these applications,with graphite being the standard anode material due to its stability.However,graphite falls short of meeting the growing demand for higher energy density,possessing a theoretical capacity that lags behind.To address this,researchers are actively seeking alternative materials to replace graphite in commercial batteries.One promising avenue involves lithiumalloying materials like silicon and phosphorus,which offer high theoretical capacities.Carbon-silicon composites have emerged as a viable option,showing improved capacity and performance over traditional graphite or pure silicon anodes.Yet,the existing methods for synthesizing these composites remain complex,energy-intensive,and costly,preventing widespread adoption.A groundbreaking approach is presented here:the use of a laser writing strategy to rapidly transform common organic carbon precursors and silicon blends into efficient“graphenic silicon”composite thin films.These films exhibit exceptional structural and energy storage properties.The resulting three-dimensional porous composite anodes showcase impressive attributes,including ultrahigh silicon content,remarkable cyclic stability(over 4500 cycles with∼40%retention),rapid charging rates(up to 10 A g^(-1)),substantial areal capacity(>5.1 mAh cm^(-2)),and excellent gravimetric capacity(>2400 mAh g^(-1) at 0.2 A g^(-1)).This strategy marks a significant step toward the scalable production of high-performance LIB materials.Leveraging widely available,cost-effective precursors,the laser-printed“graphenic silicon”composites demonstrate unparalleled performance,potentially streamlining anode production while maintaining exceptional capabilities.This innovation not only paves the way for advanced LIBs but also sets a precedent for transforming various materials into high-performing electrodes,promising reduced complexity and cost in battery production.
基金the National Natural Science Foundation of China(51872195)the National Science Fund for Distinguished Young Scholars of China(51525204)+1 种基金JSPS KAKENHI(20K05281)the Beijing Natural Science Foundation(2192061)。
文摘Increasing the density and thickness of electrodes is required to maximize the volumetric energy density of lithium-ion batteries for practical applications.However,dense and thick electrodes,especially highmass-content(>50 wt%) silicon anodes,have poor mechanical stability due to the presence of a large number of unstable interfaces between the silicon and conducting components during cycling.Here we report a network of mechanically robust carbon cages produced by the capillary shrinkage of graphene hydrogels that can contain the silicon nanoparticles in the cages and stabilize the silicon/carbon interfaces.In situ transmission electron microscope characterizations including compression and tearing of the structure and lithiation-induced silicon expansion experiments,have provided insight into the excellent confinement and buffering ability of this interface-strengthened graphene-caged silicon nanoparticle anode material.Consequently,a dense and thick silicon anode with reduced thickness fluctuations has been shown to deliver both high volumetric(>1000 mAh cm^-3) and areal(>6 mAh cm^-2)capacities together with excellent cycling capability.
基金supported by the National Natural Science Foundation of China(No.51602250)Thousand Youth Talents Plan Project of China
文摘Silicon anodes have drawn ever-increasing attention in lithium-ion batteries(LIBs) owing to their extremely high theoretical capacity and abundance in the earth. Despite promising advantages, the wide use of silicon anodes in LIBs is highly hindered by their fast capacity fading and low Coulombic efficiency arising from their substantial volumetric variation(>300%). Herein, we report a novel aqueous hybrid gel binder for silicon anodes via crosslinking sodium carboxymethyl cellulose(NaCMC) by an inorganic crosslinker-sodium borate. Not only this gel polymer binder can chemically bond to silicon nanoparticle, but also the deformable framework of this crosslinked binder is capable of maintaining electrode integrity, thus buffering dramatic volume change of silicon. Consequently, the silicon anode with this gel binder exhibits good cycle life(1211.5 mAh/g after 600 cycles) and high initial Coulombic efficiency(88.95%).
基金financially supported by the National Natural Science Foundation of China (U2004210, 51974208, U2003130, 21875080, 52002297)the Outstanding Youth Foundation of Natural Science Foundation of Hubei Province (2020CFA099)+2 种基金the Special Project of Central Government for Local Science and Technology Development of Hubei Province (2019ZYYD024)the Innovation group of Natural Science Foundation of Hubei Province (2019CFA020)the City University of Hong Kong Strategic Research Grants (7005505)。
文摘Silicon (Si) is a promising anode material for next-generation high-energy lithium-ion batteries (LIBs) due to its high capacity.However,the large volumetric expansion,poor ion conductivity and unstable solid electrolyte interface (SEI) lead to rapid capacity fading and low rate performance.Herein,we report Si nitride (SiN) comprising stoichiometric Si_(3)N_(4) and Li-active anazotic SiN_(x) coated porous Si (p-Si@SiN)for high-performance anodes in LIBs.The ant-nest-like porous Si consisting of 3D interconnected Si nanoligaments and bicontinuous nanopores prevents pulverization and accommodates volume expansion during cycling.The Si_(3)N_(4) offers mechanically protective coating to endow highly structural integrity and inhibit superfluous formation of SEI.The fast ion conducting Li_(3)N generated in situ from lithiation of active SiN_(x) facilitates Li ion transport.Consequently,the p-Si@SiN anode has appealing electrochemical properties such as a high capacity of 2180 mAh g^(-1)at 0.5 A g^(-1) with 84%capacity retention after 200cycles and excellent rate capacity with discharge capacity of 721 mAh g^(-1) after 500 cycles at 5.0 A g^(-1).This work provides insights into the rational design of active/inactive nanocoating on Si-based anode materials for fast-charging and highly stable LIBs.
基金The authors are very grateful to the National Natural Science Foundation of China(NSFC no.21875154 and 21473120)for funding.
文摘Lithium-ion battery anode used as silicon particles were obtained from different major suppliers,and they were characterized by different spectroscopic techniques and evaluated by electrochemical experiments.Correlations between the key physical parameters and electrochemical properties of the silicon particles were investigated.Silicon particle size,surface oxygen content,-OH content and physical appearance are found to strongly influence the electrochemical properties of the Si anode.The particle size of 100 nm has great promise for the practical application of Si nanoparticles in the lithium-ion battery industry.An inverse correlation between the oxygen content and the reversible capacity or first coulombic efficiency was obtained.The-OH content by surface treatment contributes to enhanced cycling stability by the improved affinity between the Si particle and the water-soluble binder.Spherical Si particles perform better compared to irregular particles,and agglomeration dramatically decreases the cycling stability of the Si anode.Among the investigated Si particles,the sample that exhibited a reversible capacity of more than 2500 mAh g^(-1),a first coulombic efficiency of 89.26%and an excellent cycling stability,has great potential for use in the battery industry.
基金This work was supported by the General Research Fund scheme of the Hong Kong Research Grants Council(Project No.15227121)the Hong Kong Polytechnic University(ZVGH).
文摘Si is a promising anode material for Li ion batteries because of its high specific capacity,abundant reserve,and low cost.However,its rate performance and cycling stability are poor due to the severe particle pulverization during the lithiation/delithiation process.The high stress induced by the Li concentration gradient and anisotropic deformation is the main reason for the fracture of Si particles.Here we present a new stress mitigation strategy by uniformly distributing small amounts of Sn and Sb in Si micron-sized particles,which reduces the Li concentration gradient and realizes an isotropic lithiation/delithiation process.The Si8.5Sn0.5Sb microparticles(mean particle size:8.22μm)show over 6000-fold and tenfold improvements in electronic conductivity and Li diffusivity than Si particles,respectively.The discharge capacities of the Si_(8.5)Sn_(0.5)Sb microparticle anode after 100 cycles at 1.0 and 3.0 A g^(-1)are 1.62 and 1.19 Ah g^(-1),respectively,corresponding to a retention rate of 94.2%and 99.6%,respectively,relative to the capacity of the first cycle after activation.Multicomponent microparticle anodes containing Si,Sn,Sb,Ge and Ag prepared using the same method yields an ultra-low capacity decay rate of 0.02%per cycle for 1000 cycles at 1 A g^(-1),corroborating the proposed mechanism.The stress regulation mechanism enabled by the industry-compatible fabrication methods opens up enormous opportunities for low-cost and high-energy-density Li-ion batteries.
基金supported by the National Key R&D Program of China(No.2018YFA0209600)the National Natural Science Foundation of China(Nos.22022813 and 21878268)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(No.2019R01006).
文摘Sulfide solid electrolyte(SE)is one of the most promising technologies for all-solid-state batteries(ASSBs)because of its high ionic conductivity and ductile mechanical properties.In order to further improve the energy density of sulfide-based ASSBs and promote practical applications,silicon anodes with ultrahigh theoretical capacity(4,200 mAh·g^(−1))and rich resource abundance have broad commercial prospects.However,significant challenges including bulk instability of sulfide SEs and poor utilization of silicon materials have severely impeded the ASSBs from becoming viable.In this review,we first introduce the critical bulk properties of sulfide SEs and the most recent improving strategies covering the ionic conductivity,air stability,electrochemical window,mechanical stability,thermostability and solvent stability.Next,we introduce the main factors affecting the compatibility of silicon and sulfide SE,including the carbon’s effect,particle size of silicon,external pressure,silicon composite matrix and the depth of silicon’s lithiation.Finally,we discuss possible research directions in the future.We hope that this review can provide a comprehensive picture of the role of nanoscale approaches in recent advances in ASSBs with sulfide and silicon,as well as a source of inspiration for future research.
基金financially supported by the National Natural Science Foundation of China(Nos.52002151 and 51905526)Jiaxing Science and Technology Project(No.2020AY10018)the Key Laboratory of Yam Materials Forming and Composite Processing Technology,Zhejiang Province(open project program,No.MTC2021-10)。
文摘Nowadays,silicon has become a promising anode active material for lithium-ion batteries due to its high specific capacity.However,traditional binder materials cannot effectively restrain the volume expansion of silicon during lithiation/delithiation.Inspired by the growth process of climbing plants,we sequentially crosslink sodium alginate with calcium ions and hyperbranched polyethyleneimine to construct a dual crosslinked network binder.During the sequentially crosslinking,sodium alginate preferentially crosslinks with Ca^(2+)to form the"trellis"network,which restricts the free movement of hyperbranched polyethyleneimine and guides it,like"vine",to gradually anchor on the surrounding"trellis"through hydrogen and ionic bonding.In this dual crosslinked network,the ionic ally crosslinked sodium alginate maintains the anode structural integrity;the anchored hyperbranched polyethyleneimine forms strong multidimensional hydrogen bonds with silicon nanoparticles through its amino-rich branch chains;and the network utilizes the bonding reversibility of hydrogen and ionic bonds to repeatedly eliminate the mechanical stress and self-heal the structure damages caused by the volume change of silicon.Benefited from the multifunction of the dual crosslinked network,the silicon anode has achieved an excellent electrochemical performance with a specific capacity of 2403 mAh·g^(-1)at the current density of500 mA·g^(-1)after 100 cycles.
