Lithium-ion capacitors(LICs)combine the high power dens-ity of electrical double-layer capacitors with the high energy density of lithium-ion batteries.However,they face practical limitations due to the narrow operati...Lithium-ion capacitors(LICs)combine the high power dens-ity of electrical double-layer capacitors with the high energy density of lithium-ion batteries.However,they face practical limitations due to the narrow operating voltage window of their activated carbon(AC)cathodes.We report a scalable thermal treatment strategy to develop high-voltage-tolerant AC cathodes.Through controlled thermal treatment of commer-cial activated carbon(Raw-AC)under a H_(2)/Ar atmosphere at 400-800℃,the targeted reduction of degradation-prone functional groups can be achieved while preserving the critical pore structure and increasing graph-itic microcrystalline ordering.The AC treated at 400℃(HAC-400)had a significant increase in specific capacity(96.0 vs.75.1 mAh/g at 0.05 A/g)and better rate capability(61.1 vs.36.1 mAh/g at 5 A/g)in half-cell LICs,along with an 83.5%capacity retention over 7400 cycles within an extended voltage range of 2.0-4.2 V in full-cell LICs.Scalability was demonstrated by a 120 g batch production,enabling fabrication of pouch-type LICs with commercial hard carbon anodes that delivered a higher energy density of 28.3 Wh/kg at 1 C,and a peak power density of 12.1 kW/kg compared to devices using raw AC.This simple,industry-compatible approach may be used for producing ad-vanced cathode materials for practical high-performance LICs.展开更多
Metal-insulator-metal aluminium electrolytic capacitors(MIM-AECs)combine high capacity-density and high breakdown field strength of solid AECs with high-frequency responsibility,wide workingtemperature window and wate...Metal-insulator-metal aluminium electrolytic capacitors(MIM-AECs)combine high capacity-density and high breakdown field strength of solid AECs with high-frequency responsibility,wide workingtemperature window and waterproof properties of MIM nanocapacitors.However,interfacial atomic diffusion poses a major obstacle,preventing the high-voltage MIM-AECs exploitation and thereby hampering their potential and advantages in high-power and high-energy-density applications.Here,an innovative high-voltage MIM-AECs were fabricated.The AlPO_(4)buffer layer is formed on AlO(OH)/AAO/Al surface by using H_(3)PO_(4)treatment,then a stable van der Waals(vdW)SnO_(2)/AlPO_(4)/AAO/Al multilayer was constructed via atomic layer deposition(ALD)technology.Due to higher diffusion barrier and lower carrier migration of SnO_(2)/AlPO_(4)/AAO interfaces,Sn atom diffusion is inhibited and carrier acceleration by electric field is weakened,guaranteeing high breakdown field strength of dielectric AAO and avoiding local breakdown risks.Through partial etching to hydrated AlO(OH)by H_(3)PO_(4)treatment,the tunnel was further opened up to facilitate subsequent ALD-SnO_(2)entry,thus obtaining a high SnO_(2)coverage.The SnO_(2)/AlPO_(4)/AAO/Al capacitors show a comprehensive performance in high-voltage(260 V),hightemperature(335℃),high-humidity(100%RH)and high-frequency response(100 k Hz),outperforming commercial solid-state AECs,and high-energy density(8.6μWh/cm^(2)),markedly exceeding previously reported MIM capacitors.The work lays the foundation for next-generation capacitors with highvoltage,high-frequency,high-temperature and high-humidity resistance.展开更多
The distribution networks sometimes suffer from excessive losses and voltage violations in densely populated areas. The aim of the present study is to improve the performance of a distribution network by successively ...The distribution networks sometimes suffer from excessive losses and voltage violations in densely populated areas. The aim of the present study is to improve the performance of a distribution network by successively applying mono-capacitor positioning, multiple positioning and reconfiguration processes using GA-based algorithms implemented in a Matlab environment. From the diagnostic study of this network, it was observed that a minimum voltage of 0.90 pu induces a voltage deviation of 5.26%, followed by active and reactive losses of 425.08 kW and 435.09 kVAR, respectively. Single placement with the NSGAII resulted in the placement of a 3000 kVAR capacitor at node 128, which proved to be the invariably neuralgic point. Multiple placements resulted in a 21.55% reduction in losses and a 0.74% regression in voltage profile performance. After topology optimization, the loss profile improved by 65.08% and the voltage profile improved by 1.05%. Genetic algorithms are efficient and effective tools for improving the performance of distribution networks, whose degradation is often dynamic due to the natural variability of loads.展开更多
Immense attention has been focused on developing supercapacitors in the field of energy storage by virtue of their exceptional power density,extended cycling stability and operational safety.However,traditional liquid...Immense attention has been focused on developing supercapacitors in the field of energy storage by virtue of their exceptional power density,extended cycling stability and operational safety.However,traditional liquid electrolytes pose severe challenges in response to leakage,high volatility and low electrochemical stability issues.To address these problems,we have developed a novel composite polymer membrane for gel polymer electrolytes(GPEs).This membrane features an internal fibrous framework composed of shape-memory polymers,while surface dielectric layers of PVDF-HFP cross-linked with modified TiO_(2)nanoparticles are constructed on both sides of the framework.This configuration modulates the Stern layer potential gradient and diffuse layer ionic distribution through dielectric polarization,thereby suppressing electrolyte decomposition at high voltages,mitigating side reactions and facilitating ionic conduction.The resultant quasi-solid-state supercapacitor demonstrates excellent electrochemical stability at a voltage of 3.5 V,achieving an energy density of 43.87 Wh kg^(-1),with a high-power density of 22.66 kW kg^(-1)along with exceptional cyclic stability and mechanical flexibility.The synergistic structural design offers a safe and efficient energy harvesting solution for wearable electronic devices and portable energy storage systems.展开更多
With the rapid development of integrated and miniaturized electronics,the planar energy storage devices with high capacitance and energy density are in enormous demand.Hence,the advanced manufacture and fast fabricati...With the rapid development of integrated and miniaturized electronics,the planar energy storage devices with high capacitance and energy density are in enormous demand.Hence,the advanced manufacture and fast fabrication of microscale planar energy units are of great significance.Herein,we develop aqueous planar micro-supercapacitors(MSCs) with ultrahigh areal capacitance and energy density via an efficient all-3 D-printing strategy,which can directly extrude the active material ink and gel electrolyte onto the substrate to prepare electrochemical energy storage devices.Both the printed active carbon/exfoliated graphene(AC/EG) electrode ink and electrolyte gel are highly processable with outstanding conductivity(~97 S cm^(-1) of electrode;-34.8 mS cm^(-1) of electrolyte),thus benefiting the corresponding shaping and electrochemical performances.Furthermore,the 3 D-printed symmetric MSCs can be operated stably at a high voltage up to 2.0 V in water-in-salt gel electrolyte,displaying ultrahigh areal capacitance of2381 mF cm^(-2) and exceptional energy density of 331 μWh cm^(-2),superior to previous printed micro energy units.In addition,we can further tailor the integrated 3 D-printed MSCs in parallel and series with various voltage and current outputs,enabling metal-free interconnection.Therefore,our all-3 D-printed MSCs place a great potential in developing high-power micro-electronics fabrication and integration.展开更多
As battery technology evolves and demand for efficient energy storage solutions,aqueous zinc ion batteries(AZIBs)have garnered significant attention due to their safety and environmental benefits.However,the stability...As battery technology evolves and demand for efficient energy storage solutions,aqueous zinc ion batteries(AZIBs)have garnered significant attention due to their safety and environmental benefits.However,the stability of cathode materials under high-voltage conditions remains a critical challenge in improving its energy density.This review systematically explores the failure mechanisms of high-voltage cathode materials in AZIBs,including hydrogen evolution reaction,phase transformation and dissolution phenomena.To address these challenges,we propose a range of advanced strategies aimed at improving the stability of cathode materials.These strategies include surface coating and doping techniques designed to fortify the surface properties and structure integrity of the cathode materials under high-voltage conditions.Additionally,we emphasize the importance of designing antioxidant electrolytes,with a focus on understanding and optimizing electrolyte decomposition mechanisms.The review also highlights the significance of modifying conductive agents and employing innovative separators to further enhance the stability of AZIBs.By integrating these cutting-edge approaches,this review anticipates substantial advancements in the stability of high-voltage cathode materials,paving the way for the broader application and development of AZIBs in energy storage.展开更多
Lithium-ion capacitors(LICs)are becoming important electrochemical energy storage systems due to their great potential to bridge the gap between supercapacitors and lithium-ion batteries.However,capacity lopsidedness ...Lithium-ion capacitors(LICs)are becoming important electrochemical energy storage systems due to their great potential to bridge the gap between supercapacitors and lithium-ion batteries.However,capacity lopsidedness and low output voltage greatly hinder the realization of high-energy-density LICs.Herein,a strategy of balancing capacity towards fastest dynamics is proposed to enable high-voltage LICs.Through electrochemical prelithiation of Nb_(2)C to be 1.1 V with 165 mAh g^(-1),Nb_(2)C//LiFePO_(4) LICs show a broadened potential window from 3.0 to 4.2 V and an according high energy density of 420 Wh kg^(-1).Moreover,the underlying mechanism between prelithiation and high voltage is disclosed by electrochemical dynamic analysis.Prelithiation declines the Nb_(2)C anode potential that facilitates electron transmission in the interlayer of two-dimensional Nb_(2)C MXene.This effect induces small drive force for Li^(+)ions deposition and hence weakens the repulsive force from adsorbed ions on the electrode surface.Benefiting from even more Li^(+)ions deposition,a higher voltage is eventually delivered.In addition,prelithiation significantly increases Coulomb efficiency of the 1st cycle from 74%to 90%,which is crucial to commercial application of LICs.展开更多
This article introduces a novel 20 V radiation-hardened high-voltage metal-oxide-semiconductor field-effect transistor(MOSFET)driver with an optimized input circuit and a drain-surrounding-source(DSS)structure.The inp...This article introduces a novel 20 V radiation-hardened high-voltage metal-oxide-semiconductor field-effect transistor(MOSFET)driver with an optimized input circuit and a drain-surrounding-source(DSS)structure.The input circuit of a conventional inverter consists of a thick-gate-oxide n-type MOSFET(NMOS).These conventional drivers can tolerate a total ionizing dose(TID)of up to 100 krad(Si).In contrast,the proposed comparator input circuit uses both a thick-gate-oxide p-type MOSFET(PMOS)and thin-gate-oxide NMOS to offer a high input voltage and higher TID tolerance.Because the thick-gate-oxide PMOS and thin-gate-oxide NMOS collectively provide better TID tolerance than the thick-gate-oxide NMOS,the circuit exhibits enhanced TID tolerance of>300 krad(Si).Simulations and experimental date indicate that the DSS structure reduces the probability of unwanted parasitic bipolar junction transistor activation,yielding a better single-event effect tolerance of over 81.8 MeVcm^(2)mg^(-1).The innovative strategy proposed in this study involves circuit and layout design optimization,and does not require any specialized process flow.Hence,the proposed circuit can be manufactured using common commercial 0.35μm BCD processes.展开更多
Expanding the cutoff voltage of layered oxide cathodes for sodium-ion batteries(SIBs)is crucial for overcoming their existing energy density limitations.However,cationic/anodic redox-triggered multiple phase transitio...Expanding the cutoff voltage of layered oxide cathodes for sodium-ion batteries(SIBs)is crucial for overcoming their existing energy density limitations.However,cationic/anodic redox-triggered multiple phase transitions and unfavorable interfacial side reactions accelerate capacity and voltage decay.Herein,we present a straightforward melting plus reactive wetting strategy using H_(3)BO_(3)for surface modification of O_(3)-type Na_(0.9)Cu_(0.12)Ni_(0.33)Mn_(0.4)Ti_(0.15)O_(2)(CNMT).The transformation of H_(3)BO_(3)from solid to liquid under mild heating facilitates the uniform dispersion and complete surface coverage of CNMT particles.By neutralizing the residual alkali and extracting Na^(+)from the CNMT lattice,H_(3)BO_(3)forms a multifunctional Na_(2)B_(2)O_(5)-dominated layer on the CNMT surface.This Na_(x)B_(y)O_(z)(NBO)layer plays a positive role in providing low-barrier Na^(+)transport channels,suppressing phase transitions,and minimizing the generation of O_(2)/CO_(2)gases and resistive byproducts.As a result,at a charge cutoff voltage of 4.5 V,the NBO-coated CNMT delivers a high discharge capacity of 149,1 mAh g^(-1)at 10 mA g^(-1)and exhibits excellent cycling stability at 100 mA g^(-1)over 200 cycles with a higher capacity retention than that of pristine CNMT(86,4%vs,62.1%).This study highlights the effectiveness of surface modification using lowmelting-point solid acids,with potential applications for other layered oxide cathode materials to achieve stable high-voltage cycling.This proposed strategy opens new avenues for the construction of highquality coatings for high-voltage layered oxide cathodes in SIBs.展开更多
Solid-state lithium batteries have become a research hotspot in the field of large-scale energy storage due to their excellent safety performance.The development of high-voltage positive electrode materials matched wi...Solid-state lithium batteries have become a research hotspot in the field of large-scale energy storage due to their excellent safety performance.The development of high-voltage positive electrode materials matched with lithium metal anode have advanced the energy density of solid-state lithium batteries close to or even exceeding that of lithium batteries based on a liquid electrolyte,which is expected to be commercialized in the future.However,in high voltage conditions(>4.3 V),the decomposition of electrolyte components,structural degradation,and interface side reactions significantly reduce battery performance and hinder its further development.This review summarizes the latest research progress of inorganic electrolytes,polymer electrolytes,and composite electrolytes in high-voltage solid-state lithium batteries.At the same time,the designs of high-voltage polymer gel electrolyte and high-voltage quasi solid-state electrolyte are introduced in detail.In addition,interface engineering is crucial for improving the overall performance of high-voltage solid-state batteries.Finally,we highlight the challenges faced by high-voltage solid-state lithium batteries and put forward our own views on future research directions.This review offers instructive insights into the advancement of high-voltage solid-state lithium batteries for large-scale energy storage applications.展开更多
Thermal batteries are a type of thermally activated reserve battery,where the cathode material significantly influences the operating voltage and specific capacity.In this work,Cu_(2)O–CuO nanowires are prepared by i...Thermal batteries are a type of thermally activated reserve battery,where the cathode material significantly influences the operating voltage and specific capacity.In this work,Cu_(2)O–CuO nanowires are prepared by in-situ thermal oxidation method onto Cu foam,which are further coated with a carbon layer derived from polydopamine(PDA).The morphology of the nanowires has been examined using scanning electron microscopy(SEM)and transmission electron microscopy(TEM).The material shows a kind of core–shell structure,with CuO as the shell and Cu_(2)O as the core.To further explore the interaction between the material and lithium-ion(Li^(+)),the Lit adsorption energies of CuO and Cu_(2)O were calculated,revealing a stronger affinity of Li^(+) for CuO.The unique core–shell nanowire structure of Cu_(2)O–CuO can provide a good Li^(+)adsorption with the outer layer CuO and excellent structural stability with the inner layer Cu_(2)O.When applied in thermal batteries,Cu_(2)O–CuO–C nanowires exhibit specific capacity and specific energy of 326 mAh g^(-1)and 697 Wh kg^(-1)at a cut-off voltage of 1.5 V both of which are higher than those of Cu_(2)O–CuO(238 mAh g^(-1)and 445 Wh kg^(-1)).The discharge process includes the insertion of lithium ions and subsequent reduction reactions,ultimately resulting in the formation of lithium oxide and copper.展开更多
This paper focuses on the high-voltage safety of drive motor systems in new energy vehicles and conducts standardized research on functional safety design in the concept phase. In view of the lack of high-voltage haza...This paper focuses on the high-voltage safety of drive motor systems in new energy vehicles and conducts standardized research on functional safety design in the concept phase. In view of the lack of high-voltage hazard analysis for drive motor systems in existing standards, based on theories such as GB/T 34590 and ISO 26262, the safety levels are deeply analyzed. The HAZOP method is innovatively used, and 16 types of guidewords are combined to comprehensively analyze the system functions, identifying vehicle hazards such as high-voltage electric shock caused by functional abnormalities, including high-voltage interlock function failure and abnormal active discharge. Subsequently, safety goals such as preventing high-voltage electric shock are set, functional safety requirements such as accurately obtaining collision signals and timely discharging high-voltage electricity are formulated, and requirements for external signal sources and other technologies are clearly defined, constructing a complete high-voltage safety protection system. The research results provide important technical support and standardized references for the high-voltage safety functional design of drive motor systems in new energy vehicles, and are of great significance for improving the high-voltage safety level of the new energy vehicle industry, expecting to play a key role in subsequent product development and standard improvement.展开更多
With the development of power systems,a large number of shunt capacitors are used to improve power quality in the distribution network.The shunt capacitor banks are operated much frequently,as a result,the capacitor b...With the development of power systems,a large number of shunt capacitors are used to improve power quality in the distribution network.The shunt capacitor banks are operated much frequently,as a result,the capacitor banks will bear large numbers of over-voltage inevitably.If the over-voltage exceeds certain amplitude,the capacitor will be damaged.This paper aims at the capacitor banks in the 35 kV side of Shanghai Xu-xing 500 kV substation,and applies ATP-EMTP to simulate the over-voltages generated by operating the switches under different angles of the source.Finally,according to the results of simulation and theoretical analysis,a best choice(i.e.angles of the source) to switch on capacitor banks is proposed.In this case the over-voltage on the capacitor will be limited to lowest.展开更多
High-voltage solid-state lithium-ion batteries(SSLIBs)have attracted considerable research attention in recent years due to their high-energy-density and superior safety characteristics.However,the integration of high...High-voltage solid-state lithium-ion batteries(SSLIBs)have attracted considerable research attention in recent years due to their high-energy-density and superior safety characteristics.However,the integration of high-voltage cathodes with solid electrolytes(SEs)presents multiple challenges,including the formation of high-impedance layers from spontaneous chemical reactions,electrochemical instability,insufficient interfacial contact,and lattice expansion.These issues significantly impair battery performance and potentially lead to battery failure,thus impeding the commercialization of high-voltage SSLIBs.The incorporation of fluorides,known for their robust bond strength and high free energy of formation,has emerged as an effective strategy to address these challenges.Fluorinated electrolytes and electrode/electrolyte interfaces have been demonstrated to significantly influence the reaction reversibility/kinetics,safety,and stability of rechargeable batteries,particularly under high voltage.This review summarizes recent advancements in fluorination treatment for high-voltage SEs,focusing on solid polymer electrolytes(SPEs),inorganic solid electrolytes(ISEs),and composite solid electrolytes(CSEs),along with the performance enhancements these strategies afford.This review aims to provide a comprehensive understanding of the structure-property relationships,the characteristics of fluorinated interfaces,and the application of fluorinated SEs in high-voltage SSLIBs.Further,the impacts of residual moisture and the challenges of fluorinated SEs are discussed.Finally,the review explores potential future directions for the development of fluorinated SSLIBs.展开更多
Enhancing the energy density of lithium-ion batteries through high-voltage cathodes holds great pro-mise.However,traditional carbonate-based electrolytes face significant challenges due to limited oxida-tive stability...Enhancing the energy density of lithium-ion batteries through high-voltage cathodes holds great pro-mise.However,traditional carbonate-based electrolytes face significant challenges due to limited oxida-tive stability and poor compatibility with high-nickel materials.This study introduces a novel electrolyte that combines bis(triethoxysilyl)methane(DMSP)as the sole solvent with lithium bis(fluorosulfonyl)imide(LiFSI)as the lithium salt.This formulation significantly improves the stability of LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)cathodes and graphite anodes.The capacity retention of the NCM811 elec-trode increases from 5%to 95%after 1000 cycles at 1 C(3.0-4.5 V),while that of the graphite anode is improved from 22%to 92%after 400 cycles at 0.2 C(0.005-3.0 V).The NCM811//graphite pouch cell exhibits enhanced retention,rising from 12%to 66%at 25℃and from 3%to 65%at 60℃after 300 cycles at 0.2 C.Spectroscopic characterization and theoretical calculations reveal that the steric hindrance of the Si-O-CH_(3)groups in DMSP creates a weakly solvating structure,promoting the formation of Lit^(+)-FSI^(-)ion pairs and aggregation clusters,which enriches the electrode interphase with LiF,Li_(3)N,and Li_(2)SO_(3).Furthermore,DMSP with abundant Si-O effectively enhances the elasticity of the interphase layer,scav-enging harmful substances such as HF and suppressing gas evolution and transition metal dissolution.The simplicity of the DMSP-based electrolyte formulation,coupled with its superior performance,ensures scalability for large-scale manufacturing and practical application in the high-voltage battery.This work provides critical insights into improving interfacial chemistry and addressing compatibility issues in high-voltageNi-rich cathodes.展开更多
Solid-state batteries(SSBs) are highly attractive on account of their high energy density and good safety.In high-voltage and high-current conditions,however,the interface reactions,structural changes,and decompositio...Solid-state batteries(SSBs) are highly attractive on account of their high energy density and good safety.In high-voltage and high-current conditions,however,the interface reactions,structural changes,and decomposition of the electrolyte impede the transmission of lithium ions in all-solid-state lithium batteries(ASSLBs),significantly reducing the charging and discharging capacity and cycling stability of the battery and therefore restricting its practical applications.The main content of review is to conduct an in-depth analysis of the existing problems of solid-state batteries from the aspects of interface reactions,material failure,ion migration,and dendrite growth,and points out the main factors influencing the electrochemical performance of ASSLBs.Additionally,the compatibility and ion conduction mechanisms between polymer electrolytes,inorganic solid electrolytes,and composite electrolytes and the electrode materials are discussed.Furthermore,the perspectives of electrode materials,electrolyte properties,and interface modification are summarized and prospected,providing new optimization directions for the future commercialization of high-voltage solid-state electrolytes.展开更多
Li/Mn-rich layered oxide(LMR)cathode active materials offer remarkably high specific discharge capacity(>250 mAh g^(-1))from both cationic and anionic redox.The latter necessitates harsh charging conditions to high...Li/Mn-rich layered oxide(LMR)cathode active materials offer remarkably high specific discharge capacity(>250 mAh g^(-1))from both cationic and anionic redox.The latter necessitates harsh charging conditions to high cathode potentials(>4.5 V vs Li|Li^(+)),which is accompanied by lattice oxygen release,phase transformation,voltage fade,and transition metal(TM)dissolution.In cells with graphite anode,TM dissolution is particularly detrimental as it initiates electrode crosstalk.Lithium difluorophosphate(LiDFP)is known for its pivotal role in suppressing electrode crosstalk through TM scavenging.In LMR‖graphite cells charged to an upper cutoff voltage(UCV)of 4.5 V,effective TM scavenging effects of LiDFP are observed.In contrast,for an UCV of 4.7 V,the scavenging effects are limited due to more severe TM dissolution compared an UCV of 4.5V.Given the saturation in solubility of the TM scavenging agents,which are LiDFP decomposition products,e.g.,PO_(4)^(3-) and PO_(3)F^(2-),higher concentrations of the LiDFP as precursor"cannot enhance the amount of scavenging species,they rather start to precipitate and damage the anode.展开更多
Lithium-ion batteries are essential for modern energy storage,yet achieving simultaneous high-temperature and high-voltage operation remains challenging due to interfacial compatibility.In this study,we introduce a po...Lithium-ion batteries are essential for modern energy storage,yet achieving simultaneous high-temperature and high-voltage operation remains challenging due to interfacial compatibility.In this study,we introduce a polyetherimide(PEI)-polyimide(PI)functional coating on the separator that enhances wettability,thermal stability,and mechanical strength,while markedly improving cathode stability under harsh conditions.By integrating theoretical calculations with experimental validation,we demonstrate that the PEI/PI coating modulates the solvation structure of lithium-ions,thereby facilitating the interfacial desolvation process.More importantly,the PEI/PI layer regulates electrolyte decomposition at the interface,promoting the formation of a uniform and thermally stable cathode-electrolyte interphase.Consequently,LiCoO_(2)cathodes exhibit improved cycling performance at 60°C.Overall,this work underscores the pivotal role of separator coatings in governing interfacial chemistry and provides a viable strategy for designing high-performance lithium-ion batteries capable of enduring both high temperatures and high.展开更多
Weakly solvating electrolyte(WSE)demonstrates superior compatibility with lithium(Li)metal batteries(LMBs).However,its application in fast-charging high-voltage LMBs is challenging.Here,we propose a diluent modified W...Weakly solvating electrolyte(WSE)demonstrates superior compatibility with lithium(Li)metal batteries(LMBs).However,its application in fast-charging high-voltage LMBs is challenging.Here,we propose a diluent modified WSE for fast-charging high-voltage LMBs,which is formed by adding diluent of 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether(TTE)into the tetrahydropyran(THP)based WSE.A relatively loose solvation structure is formed due to the formation of weak hydrogen bond between TTE and THP,which accelerates the de-solvation kinetics of Li~+.Besides,more anions are involved in solvation structure in the presence of TTE,yielding inorganic-rich interphases with improved stability.Li(30μm)||Li Ni_(0.5)Co_(0.2)Mn_(0.3)O_(2)(4.1 mAh/cm^(2))batteries with the TTE modified WSE retain over 64%capacity retention after 175 cycles under high rate of 3 C and high-voltage of 4.5 V,much better than that with pure THP based WSE.This work points out that the combination of diluent with weakly solvating solvent is a promising approach to develop high performance electrolytes for fast-charging high-voltage LMBs.展开更多
Poly(ethylene oxide)(PEO)solid electrolytes hold great promise in all-solid-state lithium batteries(ASSLBs)with high-energy and safety capabilities.However,the PEO electrolyte is hardly resistant to degrade electroche...Poly(ethylene oxide)(PEO)solid electrolytes hold great promise in all-solid-state lithium batteries(ASSLBs)with high-energy and safety capabilities.However,the PEO electrolyte is hardly resistant to degrade electrochemically at high voltages(>4 V)in ASSLBs.Herein,we design and prepare a highly efficient and stable PEO-based solid electrolyte(denoted as PEO-L/DTPEO)applied to high-voltage ASSLBs,in which the Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)-containing PEO(PEO-L)serves as a bulk of the electrolyte and the PEO with dualsalts(LiDFOB and high-concentration LiTFSI)forms an ultrathin coating layer(DT-PEO)covering on PEO-L.With 3%coating layer,the PEO-L/DT-PEO electrolyte exhibits an enhanced decomposition potential(>4.9 V vs.Li/Li^(+))originating from the high concentration of LiTFSI as well as renders Al foil current collector high anticorrosion by the introduction of LiDFOB.Upon coupling with highvoltage NCM811 cathode,the DT-PEO efficiently suppresses the interfacial degradation kinetics between electrolyte and cathode,and slows down the irreversible phase change of NCM811.The assembled PEO-L/DT-PEObased Li/NCM811 battery exhibits an excellent cycling stability of remaining 63.0%after 400 cycles at a cutoff voltage of 4.2 V as well as an initial discharge specific capacity of 164.5 mAh g^(-1)at a rate of 0.4C.This work offers a facile and feasible strategy to overcoming interface decomposition of the PEO electrolyte matching perfectly with high-voltage cathode for high-performance ASSLBs.展开更多
文摘Lithium-ion capacitors(LICs)combine the high power dens-ity of electrical double-layer capacitors with the high energy density of lithium-ion batteries.However,they face practical limitations due to the narrow operating voltage window of their activated carbon(AC)cathodes.We report a scalable thermal treatment strategy to develop high-voltage-tolerant AC cathodes.Through controlled thermal treatment of commer-cial activated carbon(Raw-AC)under a H_(2)/Ar atmosphere at 400-800℃,the targeted reduction of degradation-prone functional groups can be achieved while preserving the critical pore structure and increasing graph-itic microcrystalline ordering.The AC treated at 400℃(HAC-400)had a significant increase in specific capacity(96.0 vs.75.1 mAh/g at 0.05 A/g)and better rate capability(61.1 vs.36.1 mAh/g at 5 A/g)in half-cell LICs,along with an 83.5%capacity retention over 7400 cycles within an extended voltage range of 2.0-4.2 V in full-cell LICs.Scalability was demonstrated by a 120 g batch production,enabling fabrication of pouch-type LICs with commercial hard carbon anodes that delivered a higher energy density of 28.3 Wh/kg at 1 C,and a peak power density of 12.1 kW/kg compared to devices using raw AC.This simple,industry-compatible approach may be used for producing ad-vanced cathode materials for practical high-performance LICs.
基金supported by the National Natural Science Foundation of China(52477221,52202296)the Natural Science Foundation of Shaanxi Province(2023KXJ-246,2022JQ-048)。
文摘Metal-insulator-metal aluminium electrolytic capacitors(MIM-AECs)combine high capacity-density and high breakdown field strength of solid AECs with high-frequency responsibility,wide workingtemperature window and waterproof properties of MIM nanocapacitors.However,interfacial atomic diffusion poses a major obstacle,preventing the high-voltage MIM-AECs exploitation and thereby hampering their potential and advantages in high-power and high-energy-density applications.Here,an innovative high-voltage MIM-AECs were fabricated.The AlPO_(4)buffer layer is formed on AlO(OH)/AAO/Al surface by using H_(3)PO_(4)treatment,then a stable van der Waals(vdW)SnO_(2)/AlPO_(4)/AAO/Al multilayer was constructed via atomic layer deposition(ALD)technology.Due to higher diffusion barrier and lower carrier migration of SnO_(2)/AlPO_(4)/AAO interfaces,Sn atom diffusion is inhibited and carrier acceleration by electric field is weakened,guaranteeing high breakdown field strength of dielectric AAO and avoiding local breakdown risks.Through partial etching to hydrated AlO(OH)by H_(3)PO_(4)treatment,the tunnel was further opened up to facilitate subsequent ALD-SnO_(2)entry,thus obtaining a high SnO_(2)coverage.The SnO_(2)/AlPO_(4)/AAO/Al capacitors show a comprehensive performance in high-voltage(260 V),hightemperature(335℃),high-humidity(100%RH)and high-frequency response(100 k Hz),outperforming commercial solid-state AECs,and high-energy density(8.6μWh/cm^(2)),markedly exceeding previously reported MIM capacitors.The work lays the foundation for next-generation capacitors with highvoltage,high-frequency,high-temperature and high-humidity resistance.
文摘The distribution networks sometimes suffer from excessive losses and voltage violations in densely populated areas. The aim of the present study is to improve the performance of a distribution network by successively applying mono-capacitor positioning, multiple positioning and reconfiguration processes using GA-based algorithms implemented in a Matlab environment. From the diagnostic study of this network, it was observed that a minimum voltage of 0.90 pu induces a voltage deviation of 5.26%, followed by active and reactive losses of 425.08 kW and 435.09 kVAR, respectively. Single placement with the NSGAII resulted in the placement of a 3000 kVAR capacitor at node 128, which proved to be the invariably neuralgic point. Multiple placements resulted in a 21.55% reduction in losses and a 0.74% regression in voltage profile performance. After topology optimization, the loss profile improved by 65.08% and the voltage profile improved by 1.05%. Genetic algorithms are efficient and effective tools for improving the performance of distribution networks, whose degradation is often dynamic due to the natural variability of loads.
基金financially supported by the Key Research and Development Program of Shaanxi(No.2022GXLH-01-23)the Fundamental Research Funds for the Central Universities,CHD(No.300102384106)+1 种基金the Innovation Capability Support Program of Shaanxi(No.2022KXJ-144)the National Natural Science Foundation of China(No.22209101)
文摘Immense attention has been focused on developing supercapacitors in the field of energy storage by virtue of their exceptional power density,extended cycling stability and operational safety.However,traditional liquid electrolytes pose severe challenges in response to leakage,high volatility and low electrochemical stability issues.To address these problems,we have developed a novel composite polymer membrane for gel polymer electrolytes(GPEs).This membrane features an internal fibrous framework composed of shape-memory polymers,while surface dielectric layers of PVDF-HFP cross-linked with modified TiO_(2)nanoparticles are constructed on both sides of the framework.This configuration modulates the Stern layer potential gradient and diffuse layer ionic distribution through dielectric polarization,thereby suppressing electrolyte decomposition at high voltages,mitigating side reactions and facilitating ionic conduction.The resultant quasi-solid-state supercapacitor demonstrates excellent electrochemical stability at a voltage of 3.5 V,achieving an energy density of 43.87 Wh kg^(-1),with a high-power density of 22.66 kW kg^(-1)along with exceptional cyclic stability and mechanical flexibility.The synergistic structural design offers a safe and efficient energy harvesting solution for wearable electronic devices and portable energy storage systems.
基金financially supported by the National Key R@D Program of China (2016YFB0100100, 2016YFA0200200)the National Natural Science Foundation of China (51872283,22075279, 21805273, 22005297, 22005298)+7 种基金the Liao Ning Revitalization Talents Program (XLYC1807153)the Central Government of Liaoning Province Guides The Funds for Local Science and Technology Development (2021JH6/10500112)the Dalian Innovation Support Plan for High Level Talents (2019RT09)the Dalian National Laboratory For Clean Energy (DNL),CASDNL Cooperation Fund,CAS (DNL201912, DNL201915, DNL202016, DNL202019)DICP (DICP ZZBS201708, DICP ZZBS201802, DICP I2020032)the Joint Fund of the Yulin University and the Dalian National Laboratory for Clean Energy (YLU-DNL Fund 2021002)the China Postdoctoral Science Foundation (2019 M661141, 2020 M680995)。
文摘With the rapid development of integrated and miniaturized electronics,the planar energy storage devices with high capacitance and energy density are in enormous demand.Hence,the advanced manufacture and fast fabrication of microscale planar energy units are of great significance.Herein,we develop aqueous planar micro-supercapacitors(MSCs) with ultrahigh areal capacitance and energy density via an efficient all-3 D-printing strategy,which can directly extrude the active material ink and gel electrolyte onto the substrate to prepare electrochemical energy storage devices.Both the printed active carbon/exfoliated graphene(AC/EG) electrode ink and electrolyte gel are highly processable with outstanding conductivity(~97 S cm^(-1) of electrode;-34.8 mS cm^(-1) of electrolyte),thus benefiting the corresponding shaping and electrochemical performances.Furthermore,the 3 D-printed symmetric MSCs can be operated stably at a high voltage up to 2.0 V in water-in-salt gel electrolyte,displaying ultrahigh areal capacitance of2381 mF cm^(-2) and exceptional energy density of 331 μWh cm^(-2),superior to previous printed micro energy units.In addition,we can further tailor the integrated 3 D-printed MSCs in parallel and series with various voltage and current outputs,enabling metal-free interconnection.Therefore,our all-3 D-printed MSCs place a great potential in developing high-power micro-electronics fabrication and integration.
基金supported by the Exchange Program of Highend Foreign Experts of Ministry of Science and Technology of People’s Republic of China(No.G2023041003L)the Natural Science Foundation of Shaanxi Provincial Department of Education(No.23JK0367)+1 种基金the Scientific Research Startup Program for Introduced Talents of Shaanxi University of Technology(Nos.SLGRCQD2208,SLGRCQD2306,SLGRCQD2133)Contaminated Soil Remediation and Resource Utilization Innovation Team at Shaanxi University of Technology。
文摘As battery technology evolves and demand for efficient energy storage solutions,aqueous zinc ion batteries(AZIBs)have garnered significant attention due to their safety and environmental benefits.However,the stability of cathode materials under high-voltage conditions remains a critical challenge in improving its energy density.This review systematically explores the failure mechanisms of high-voltage cathode materials in AZIBs,including hydrogen evolution reaction,phase transformation and dissolution phenomena.To address these challenges,we propose a range of advanced strategies aimed at improving the stability of cathode materials.These strategies include surface coating and doping techniques designed to fortify the surface properties and structure integrity of the cathode materials under high-voltage conditions.Additionally,we emphasize the importance of designing antioxidant electrolytes,with a focus on understanding and optimizing electrolyte decomposition mechanisms.The review also highlights the significance of modifying conductive agents and employing innovative separators to further enhance the stability of AZIBs.By integrating these cutting-edge approaches,this review anticipates substantial advancements in the stability of high-voltage cathode materials,paving the way for the broader application and development of AZIBs in energy storage.
基金financial supported from the National Natural Science Foundation of China (Nos. 51977185 and 51972277)the financial supported from Southwest Jiaotong University Science and Technology Rising Star Program (No. 2682021CG021)
文摘Lithium-ion capacitors(LICs)are becoming important electrochemical energy storage systems due to their great potential to bridge the gap between supercapacitors and lithium-ion batteries.However,capacity lopsidedness and low output voltage greatly hinder the realization of high-energy-density LICs.Herein,a strategy of balancing capacity towards fastest dynamics is proposed to enable high-voltage LICs.Through electrochemical prelithiation of Nb_(2)C to be 1.1 V with 165 mAh g^(-1),Nb_(2)C//LiFePO_(4) LICs show a broadened potential window from 3.0 to 4.2 V and an according high energy density of 420 Wh kg^(-1).Moreover,the underlying mechanism between prelithiation and high voltage is disclosed by electrochemical dynamic analysis.Prelithiation declines the Nb_(2)C anode potential that facilitates electron transmission in the interlayer of two-dimensional Nb_(2)C MXene.This effect induces small drive force for Li^(+)ions deposition and hence weakens the repulsive force from adsorbed ions on the electrode surface.Benefiting from even more Li^(+)ions deposition,a higher voltage is eventually delivered.In addition,prelithiation significantly increases Coulomb efficiency of the 1st cycle from 74%to 90%,which is crucial to commercial application of LICs.
基金supported by the National Natural Science Foundation of China(U2241221).
文摘This article introduces a novel 20 V radiation-hardened high-voltage metal-oxide-semiconductor field-effect transistor(MOSFET)driver with an optimized input circuit and a drain-surrounding-source(DSS)structure.The input circuit of a conventional inverter consists of a thick-gate-oxide n-type MOSFET(NMOS).These conventional drivers can tolerate a total ionizing dose(TID)of up to 100 krad(Si).In contrast,the proposed comparator input circuit uses both a thick-gate-oxide p-type MOSFET(PMOS)and thin-gate-oxide NMOS to offer a high input voltage and higher TID tolerance.Because the thick-gate-oxide PMOS and thin-gate-oxide NMOS collectively provide better TID tolerance than the thick-gate-oxide NMOS,the circuit exhibits enhanced TID tolerance of>300 krad(Si).Simulations and experimental date indicate that the DSS structure reduces the probability of unwanted parasitic bipolar junction transistor activation,yielding a better single-event effect tolerance of over 81.8 MeVcm^(2)mg^(-1).The innovative strategy proposed in this study involves circuit and layout design optimization,and does not require any specialized process flow.Hence,the proposed circuit can be manufactured using common commercial 0.35μm BCD processes.
基金supported by the National Natural Science Foundation of China(22169002 and 22469003)the Chongzuo Key Research and Development Program of China(20241205 and 20231204)the Counterpart Aid Project for Discipline Construction from Guangxi University(2023M02)。
文摘Expanding the cutoff voltage of layered oxide cathodes for sodium-ion batteries(SIBs)is crucial for overcoming their existing energy density limitations.However,cationic/anodic redox-triggered multiple phase transitions and unfavorable interfacial side reactions accelerate capacity and voltage decay.Herein,we present a straightforward melting plus reactive wetting strategy using H_(3)BO_(3)for surface modification of O_(3)-type Na_(0.9)Cu_(0.12)Ni_(0.33)Mn_(0.4)Ti_(0.15)O_(2)(CNMT).The transformation of H_(3)BO_(3)from solid to liquid under mild heating facilitates the uniform dispersion and complete surface coverage of CNMT particles.By neutralizing the residual alkali and extracting Na^(+)from the CNMT lattice,H_(3)BO_(3)forms a multifunctional Na_(2)B_(2)O_(5)-dominated layer on the CNMT surface.This Na_(x)B_(y)O_(z)(NBO)layer plays a positive role in providing low-barrier Na^(+)transport channels,suppressing phase transitions,and minimizing the generation of O_(2)/CO_(2)gases and resistive byproducts.As a result,at a charge cutoff voltage of 4.5 V,the NBO-coated CNMT delivers a high discharge capacity of 149,1 mAh g^(-1)at 10 mA g^(-1)and exhibits excellent cycling stability at 100 mA g^(-1)over 200 cycles with a higher capacity retention than that of pristine CNMT(86,4%vs,62.1%).This study highlights the effectiveness of surface modification using lowmelting-point solid acids,with potential applications for other layered oxide cathode materials to achieve stable high-voltage cycling.This proposed strategy opens new avenues for the construction of highquality coatings for high-voltage layered oxide cathodes in SIBs.
基金supported by the National Key R&D Program of China(2024YFA1211100)the National Natural Science Foundation of China(52301278,22479080,52202254,92372001,22393900,and 92372203)+2 种基金the Natural Science Foundation of Jiangsu Province(BK20230937,BK20220966)the Science and Technology Plans of Tianjin(23JCYBJC00170,24JCJQJC00220,and 24ZXZSSS00390)the Fundamental Research Funds for the Central Universities(02063253167,30922010708)。
文摘Solid-state lithium batteries have become a research hotspot in the field of large-scale energy storage due to their excellent safety performance.The development of high-voltage positive electrode materials matched with lithium metal anode have advanced the energy density of solid-state lithium batteries close to or even exceeding that of lithium batteries based on a liquid electrolyte,which is expected to be commercialized in the future.However,in high voltage conditions(>4.3 V),the decomposition of electrolyte components,structural degradation,and interface side reactions significantly reduce battery performance and hinder its further development.This review summarizes the latest research progress of inorganic electrolytes,polymer electrolytes,and composite electrolytes in high-voltage solid-state lithium batteries.At the same time,the designs of high-voltage polymer gel electrolyte and high-voltage quasi solid-state electrolyte are introduced in detail.In addition,interface engineering is crucial for improving the overall performance of high-voltage solid-state batteries.Finally,we highlight the challenges faced by high-voltage solid-state lithium batteries and put forward our own views on future research directions.This review offers instructive insights into the advancement of high-voltage solid-state lithium batteries for large-scale energy storage applications.
基金supported by National Natural Science Foundation of China(Nos.52374298)National Natural Science Foundation of Chongqing(Nos.CSTB2023NSCQ-MSX0662)Beijing Natural Science Foundation(Nos.L243019).
文摘Thermal batteries are a type of thermally activated reserve battery,where the cathode material significantly influences the operating voltage and specific capacity.In this work,Cu_(2)O–CuO nanowires are prepared by in-situ thermal oxidation method onto Cu foam,which are further coated with a carbon layer derived from polydopamine(PDA).The morphology of the nanowires has been examined using scanning electron microscopy(SEM)and transmission electron microscopy(TEM).The material shows a kind of core–shell structure,with CuO as the shell and Cu_(2)O as the core.To further explore the interaction between the material and lithium-ion(Li^(+)),the Lit adsorption energies of CuO and Cu_(2)O were calculated,revealing a stronger affinity of Li^(+) for CuO.The unique core–shell nanowire structure of Cu_(2)O–CuO can provide a good Li^(+)adsorption with the outer layer CuO and excellent structural stability with the inner layer Cu_(2)O.When applied in thermal batteries,Cu_(2)O–CuO–C nanowires exhibit specific capacity and specific energy of 326 mAh g^(-1)and 697 Wh kg^(-1)at a cut-off voltage of 1.5 V both of which are higher than those of Cu_(2)O–CuO(238 mAh g^(-1)and 445 Wh kg^(-1)).The discharge process includes the insertion of lithium ions and subsequent reduction reactions,ultimately resulting in the formation of lithium oxide and copper.
文摘This paper focuses on the high-voltage safety of drive motor systems in new energy vehicles and conducts standardized research on functional safety design in the concept phase. In view of the lack of high-voltage hazard analysis for drive motor systems in existing standards, based on theories such as GB/T 34590 and ISO 26262, the safety levels are deeply analyzed. The HAZOP method is innovatively used, and 16 types of guidewords are combined to comprehensively analyze the system functions, identifying vehicle hazards such as high-voltage electric shock caused by functional abnormalities, including high-voltage interlock function failure and abnormal active discharge. Subsequently, safety goals such as preventing high-voltage electric shock are set, functional safety requirements such as accurately obtaining collision signals and timely discharging high-voltage electricity are formulated, and requirements for external signal sources and other technologies are clearly defined, constructing a complete high-voltage safety protection system. The research results provide important technical support and standardized references for the high-voltage safety functional design of drive motor systems in new energy vehicles, and are of great significance for improving the high-voltage safety level of the new energy vehicle industry, expecting to play a key role in subsequent product development and standard improvement.
基金supported of the Fundamental Research Founds for the Central Universities
文摘With the development of power systems,a large number of shunt capacitors are used to improve power quality in the distribution network.The shunt capacitor banks are operated much frequently,as a result,the capacitor banks will bear large numbers of over-voltage inevitably.If the over-voltage exceeds certain amplitude,the capacitor will be damaged.This paper aims at the capacitor banks in the 35 kV side of Shanghai Xu-xing 500 kV substation,and applies ATP-EMTP to simulate the over-voltages generated by operating the switches under different angles of the source.Finally,according to the results of simulation and theoretical analysis,a best choice(i.e.angles of the source) to switch on capacitor banks is proposed.In this case the over-voltage on the capacitor will be limited to lowest.
基金supported by the A*STAR MTC Programmatic Project(No.M23L9b0052)the Indonesia-NTU Singapore Institute of Research for Sustainability and Innovation(INSPIRASI)(No.6635/E3/KL.02.02/2023)+2 种基金the Singapore NRF Singapore-China Flagship Program(No.023740-00001)the National Natural Science Foundation of China(Nos.11975043 and 11475300)the China Scholarship Council(No.202306460087)。
文摘High-voltage solid-state lithium-ion batteries(SSLIBs)have attracted considerable research attention in recent years due to their high-energy-density and superior safety characteristics.However,the integration of high-voltage cathodes with solid electrolytes(SEs)presents multiple challenges,including the formation of high-impedance layers from spontaneous chemical reactions,electrochemical instability,insufficient interfacial contact,and lattice expansion.These issues significantly impair battery performance and potentially lead to battery failure,thus impeding the commercialization of high-voltage SSLIBs.The incorporation of fluorides,known for their robust bond strength and high free energy of formation,has emerged as an effective strategy to address these challenges.Fluorinated electrolytes and electrode/electrolyte interfaces have been demonstrated to significantly influence the reaction reversibility/kinetics,safety,and stability of rechargeable batteries,particularly under high voltage.This review summarizes recent advancements in fluorination treatment for high-voltage SEs,focusing on solid polymer electrolytes(SPEs),inorganic solid electrolytes(ISEs),and composite solid electrolytes(CSEs),along with the performance enhancements these strategies afford.This review aims to provide a comprehensive understanding of the structure-property relationships,the characteristics of fluorinated interfaces,and the application of fluorinated SEs in high-voltage SSLIBs.Further,the impacts of residual moisture and the challenges of fluorinated SEs are discussed.Finally,the review explores potential future directions for the development of fluorinated SSLIBs.
基金supported by the National Natural Science Foundation of China (Grant No. 22179041)the Guangzhou Science and Technology Plan Project (Grant No. 2024A04J4354)the Guangdong Basic and Applied Basic Research Foundation (Grant No. 2024A1515010034)
文摘Enhancing the energy density of lithium-ion batteries through high-voltage cathodes holds great pro-mise.However,traditional carbonate-based electrolytes face significant challenges due to limited oxida-tive stability and poor compatibility with high-nickel materials.This study introduces a novel electrolyte that combines bis(triethoxysilyl)methane(DMSP)as the sole solvent with lithium bis(fluorosulfonyl)imide(LiFSI)as the lithium salt.This formulation significantly improves the stability of LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)cathodes and graphite anodes.The capacity retention of the NCM811 elec-trode increases from 5%to 95%after 1000 cycles at 1 C(3.0-4.5 V),while that of the graphite anode is improved from 22%to 92%after 400 cycles at 0.2 C(0.005-3.0 V).The NCM811//graphite pouch cell exhibits enhanced retention,rising from 12%to 66%at 25℃and from 3%to 65%at 60℃after 300 cycles at 0.2 C.Spectroscopic characterization and theoretical calculations reveal that the steric hindrance of the Si-O-CH_(3)groups in DMSP creates a weakly solvating structure,promoting the formation of Lit^(+)-FSI^(-)ion pairs and aggregation clusters,which enriches the electrode interphase with LiF,Li_(3)N,and Li_(2)SO_(3).Furthermore,DMSP with abundant Si-O effectively enhances the elasticity of the interphase layer,scav-enging harmful substances such as HF and suppressing gas evolution and transition metal dissolution.The simplicity of the DMSP-based electrolyte formulation,coupled with its superior performance,ensures scalability for large-scale manufacturing and practical application in the high-voltage battery.This work provides critical insights into improving interfacial chemistry and addressing compatibility issues in high-voltageNi-rich cathodes.
基金financial support received from the National Key R&D Program of China (2023YFB2504000)the financial support from the National Outstanding Youth Foundation of China (52125104)+2 种基金the National Natural Science Foundation of China (52071285)the Fundamental Research Funds for the Central Universities (226-2024-00075)the National Youth Top-Notch Talent Support Program。
文摘Solid-state batteries(SSBs) are highly attractive on account of their high energy density and good safety.In high-voltage and high-current conditions,however,the interface reactions,structural changes,and decomposition of the electrolyte impede the transmission of lithium ions in all-solid-state lithium batteries(ASSLBs),significantly reducing the charging and discharging capacity and cycling stability of the battery and therefore restricting its practical applications.The main content of review is to conduct an in-depth analysis of the existing problems of solid-state batteries from the aspects of interface reactions,material failure,ion migration,and dendrite growth,and points out the main factors influencing the electrochemical performance of ASSLBs.Additionally,the compatibility and ion conduction mechanisms between polymer electrolytes,inorganic solid electrolytes,and composite electrolytes and the electrode materials are discussed.Furthermore,the perspectives of electrode materials,electrolyte properties,and interface modification are summarized and prospected,providing new optimization directions for the future commercialization of high-voltage solid-state electrolytes.
基金the Ministry for Culture and Science of North Rhine Westphalia(Germany)for funding this work within the International Graduate School for Battery Chemistry,Characterization,Analysis,Recycling,and Application(BACCARA)Open Access funding enabled and organized by Projekt DEAL。
文摘Li/Mn-rich layered oxide(LMR)cathode active materials offer remarkably high specific discharge capacity(>250 mAh g^(-1))from both cationic and anionic redox.The latter necessitates harsh charging conditions to high cathode potentials(>4.5 V vs Li|Li^(+)),which is accompanied by lattice oxygen release,phase transformation,voltage fade,and transition metal(TM)dissolution.In cells with graphite anode,TM dissolution is particularly detrimental as it initiates electrode crosstalk.Lithium difluorophosphate(LiDFP)is known for its pivotal role in suppressing electrode crosstalk through TM scavenging.In LMR‖graphite cells charged to an upper cutoff voltage(UCV)of 4.5 V,effective TM scavenging effects of LiDFP are observed.In contrast,for an UCV of 4.7 V,the scavenging effects are limited due to more severe TM dissolution compared an UCV of 4.5V.Given the saturation in solubility of the TM scavenging agents,which are LiDFP decomposition products,e.g.,PO_(4)^(3-) and PO_(3)F^(2-),higher concentrations of the LiDFP as precursor"cannot enhance the amount of scavenging species,they rather start to precipitate and damage the anode.
基金supported by the Shenzhen Science and Technology Planning Project(Grant No.JSGG20220831095604008)the National Natural Science Foundation of China(Grant No.51902296)+2 种基金the National Center for International Research of Electric Vehicle Power Batteries and Materials(Grant No.2015B01015)the Guangdong Key Laboratory of Design and Calculation of New Energy Materials(Grant No.2017B030301013)the Shenzhen Key Laboratory of New Energy Resources Genome Preparation and Testing(Grant No.ZDSYS201707281026184).
文摘Lithium-ion batteries are essential for modern energy storage,yet achieving simultaneous high-temperature and high-voltage operation remains challenging due to interfacial compatibility.In this study,we introduce a polyetherimide(PEI)-polyimide(PI)functional coating on the separator that enhances wettability,thermal stability,and mechanical strength,while markedly improving cathode stability under harsh conditions.By integrating theoretical calculations with experimental validation,we demonstrate that the PEI/PI coating modulates the solvation structure of lithium-ions,thereby facilitating the interfacial desolvation process.More importantly,the PEI/PI layer regulates electrolyte decomposition at the interface,promoting the formation of a uniform and thermally stable cathode-electrolyte interphase.Consequently,LiCoO_(2)cathodes exhibit improved cycling performance at 60°C.Overall,this work underscores the pivotal role of separator coatings in governing interfacial chemistry and provides a viable strategy for designing high-performance lithium-ion batteries capable of enduring both high temperatures and high.
基金supported by Hengyang City,Hunan Province Science and Technology Innovation Project(No.202250045319)the National Natural Science Foundation of China(Nos.11375084,21808125)the Scientific Research Planning Project of Jilin Provincial Education Department(No.JJKH20241249KJ)。
文摘Weakly solvating electrolyte(WSE)demonstrates superior compatibility with lithium(Li)metal batteries(LMBs).However,its application in fast-charging high-voltage LMBs is challenging.Here,we propose a diluent modified WSE for fast-charging high-voltage LMBs,which is formed by adding diluent of 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether(TTE)into the tetrahydropyran(THP)based WSE.A relatively loose solvation structure is formed due to the formation of weak hydrogen bond between TTE and THP,which accelerates the de-solvation kinetics of Li~+.Besides,more anions are involved in solvation structure in the presence of TTE,yielding inorganic-rich interphases with improved stability.Li(30μm)||Li Ni_(0.5)Co_(0.2)Mn_(0.3)O_(2)(4.1 mAh/cm^(2))batteries with the TTE modified WSE retain over 64%capacity retention after 175 cycles under high rate of 3 C and high-voltage of 4.5 V,much better than that with pure THP based WSE.This work points out that the combination of diluent with weakly solvating solvent is a promising approach to develop high performance electrolytes for fast-charging high-voltage LMBs.
基金financially supported by the National Natural Science Foundation of China(Nos.22176011 and 22378019)the Opening Project of State Key Laboratory of Organic-Inorganic Composites
文摘Poly(ethylene oxide)(PEO)solid electrolytes hold great promise in all-solid-state lithium batteries(ASSLBs)with high-energy and safety capabilities.However,the PEO electrolyte is hardly resistant to degrade electrochemically at high voltages(>4 V)in ASSLBs.Herein,we design and prepare a highly efficient and stable PEO-based solid electrolyte(denoted as PEO-L/DTPEO)applied to high-voltage ASSLBs,in which the Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12)(LLZTO)-containing PEO(PEO-L)serves as a bulk of the electrolyte and the PEO with dualsalts(LiDFOB and high-concentration LiTFSI)forms an ultrathin coating layer(DT-PEO)covering on PEO-L.With 3%coating layer,the PEO-L/DT-PEO electrolyte exhibits an enhanced decomposition potential(>4.9 V vs.Li/Li^(+))originating from the high concentration of LiTFSI as well as renders Al foil current collector high anticorrosion by the introduction of LiDFOB.Upon coupling with highvoltage NCM811 cathode,the DT-PEO efficiently suppresses the interfacial degradation kinetics between electrolyte and cathode,and slows down the irreversible phase change of NCM811.The assembled PEO-L/DT-PEObased Li/NCM811 battery exhibits an excellent cycling stability of remaining 63.0%after 400 cycles at a cutoff voltage of 4.2 V as well as an initial discharge specific capacity of 164.5 mAh g^(-1)at a rate of 0.4C.This work offers a facile and feasible strategy to overcoming interface decomposition of the PEO electrolyte matching perfectly with high-voltage cathode for high-performance ASSLBs.