Integrated interface configuration by in-situ interface chemistry enabling uniform lithium deposition in all-solid-state lithium metal batteries

All-solid-state lithium metal batteries(ASSLMBs)are considered as one of the ultimate goals for the development of energy storage systems due to their high energy density and high safety.However,the mismatching of interface transport kinetics as well as interfacial instability induces the growth of lithium dendrite and thus,leads to severe degradation of battery electrochemical performances.Herein,an integrated interface configuration(IIC)consisting of in-situ generated Li I interphase and Li-Ag alloy anode is proposed through in-situ interface chemistry.The IIC is capable of not only regulating charge transport kinetics but also synchronously stabilizing the lithium/electrolyte interface,thereby achieving uniform lithium platting.Therefore,Li||Li symmetric cells with IIC achieve a critical current density of up to 1.6 mA cm^(-2)and achieve stable cycling over 1600 hours at a high current density of 0.5 mA cm^(-2).Moreover,a high discharge capacity of 140.1 mA h g-1at 0.1 C is also obtained for the Li(Ni_(0.6)Co_(0.2)Mn_(0.2))O_(2)(NCM622)full battery with a capacity retention of 65.6%after 300 cycles.This work provides an effective method to synergistically regulate the interface transport kinetics and inhibit lithium dendrite growth for high-performance ASSLMBs.

Dry electrode technology for scalable and flexible high-energy sulfur cathodes in all-solid-state lithium-sulfur batteries

All-solid-state lithium-sulfur batteries(ASSLSBs)employing sulfide solid electrolytes are one of the most promising next-generation energy storage systems due to their potential for higher energy density and safety.However,scalable fabrication of sheet-type sulfur cathodes with high sulfur loading and excellent performances remains challenging.In this work,sheet-type freestanding sulfur cathodes with high sulfur loading were fabricated by dry electrode technology.The unique fibrous morphologies of polytetrafluoroethylene(PTFE)binders in dry electrodes not only provides excellent mechanical properties but also uncompromised ionic/electronic conductance.Even employed with thickened dry cathodes with high sulfur loading of 2 mg cm^(-2),ASSLSBs still exhibit outstanding rate performance and cycle stability.Moreover,the all-solid-state lithium-sulfur monolayer pouch cells(9.2 m Ah)were also demonstrated and exhibited excellent safety under a harsh test situation.This work verifies the potential of dry electrode technology in the scalable fabrication of thickened sulfur cathodes and will promote the practical applications of ASSLSBs.

Thermal safety of dendritic lithium against non-aqueous electrolyte in pouch-type lithium metal batteries

A quantitative relationship between safety issues and dendritic lithium(Li) has been rarely investigated yet. Herein the thermal stability of Li deposits with distinct surface area against non-aqueous electrolyte in pouch-type Li metal batteries is probed. The thermal runaway temperatures of Li metal batteries obtained by accelerating rate calorimeter are reduced from 211 ℃ for Li foil to 111 ℃ for cycled Li.The initial exothermic temperature is reduced from 194 ℃ for routine Li foil to 142 ℃ for 49.5 m~2g^(-1) dendrite. Li with different specific surface areas can regulate the reaction routes during the temperature range from 50 to 300 ℃. The mass percent of Li foil and highly dendritic Li reacting with ethylene carbonate is higher than that of moderately dendritic Li. This contribution can strengthen the understanding of the thermal runaway mechanism and shed fresh light on the rational design of safe Li metal batteries.

有晶状体眼后房型人工晶状体植入术后早期拱高影响因素分析

目的:观察有晶状体眼后房型人工晶状体(ICL/TICL V4c)植入术后拱高的早期变化趋势并分析相关影响因素。方法:回顾性研究。选取2020-10/2021-03于兰州华厦眼科医院接受ICL/TICL V4c植入术患者49例98眼。收集患者术前等效球镜度数(SE)、眼压、眼轴、前房深度(ACD)、晶状体厚度(LT)、中央角膜厚度、前房角(ACA)、前房容积(ACV)、角膜白到白直径(WTW)、平均角膜曲率K1、K2,术中植入的ICL尺寸,术后1、3d, 1wk, 1mo用AS-OCT测量患者拱高(vault)。按术后1mo拱高值大小分为低拱高组(<250μm)12眼、正常拱高组(250~750μm)62眼、高拱高组(>750μm)24眼,分析影响术后拱高的因素。结果:术后1、3d, 1wk, 1mo平均拱高值分别为591.05±293.44、599.62±309.78、592.22±301.49和586.69±285.63μm。术后1mo不同拱高间WTW、ACA、ACV、ACD、ICL尺寸、LT有差异(均P<0.05)。术后1mo拱高的回归方程=-3142.19+388.25×WTW+10.40×ACA-301.63×LT,R、R^(2)、调整R^(2)分别为0.674、0.454、0.436。WTW对术后1mo拱高影响最大(β=0.47,P<0.001),其次为LT(β=-0.34,P<0.001)和ACA(β=0.17,P=0.047)。结论:WTW、ACA、LT是影响和预测ICL/TICL V4c植入术后1mo拱高的主要因素。

Electrolyte inhomogeneity induced lithium plating in fast charging lithium-ion batteries

Fast charging capability of lithium-ion batteries is in urgent need for widespread economic success of electric vehicles. However, the application of the fast charging technology often leads to the inevitable lithium plating on the graphite anode, which is one of the main culprits that endanger battery safety and shorten battery lifespan. The in-depth understanding of the initiation of lithium metal nucleation and the following plating behavior is a key to the development of fast charging cells. Herein, we investigate the overlooked effect of the non-uniform distribution of electrolyte on lithium plating during fast charging. Prior lithium plating occurs on the saturated lithium-graphite compounds in the anode region with sufficient electrolyte since the lithium-ion transport is blocked in the anode region lacking electrolyte. The uniform distribution of electrolyte is crucial for the construction of safe lithium-ion batteries especially in fast charging scenarios.

Plating current density distribution of lithium metal anodes in pouch cells

The uniformity of current density distribution upon electrodes is one of the most important factors determining the lithium dendrites growth and cycling performance of lithium metal batteries(LMBs). Herein,current density distributions of lithium metal anodes induced by various engineering factors, consisting of uneven cathode, electrolyte distribution, and different tab positions, and their effects on the electrochemical performance are investigated theoretically and experimentally in pouch cells. The deviation of current density in lithium metal anodes ranges from 2.47% to 196.18% due to the different levels of uneven cathode materials. However, the deviation is just 13.60% for different electrolyte thicknesses between cathodes and anodes, even a ten-layer separator in some positions. The maximum deviation for variational tab positions is only 0.17%. The nonuniformity in current density distribution results in severe dendrite growth issues and poor electrochemical performance of LMBs. This work not only confirms the direct correlation between the uneven current density distribution and lithium deposition behaviors, but also points out the decisive effects of cathode surface roughness on current distribution of anodes, to which more attentions should be paid in practical applications of LMBs.

Dual-layer vermiculite nanosheet based hybrid film to suppress dendrite growth in lithium metal batteries

Lithium metal anode has become a favorable candidate for next-generation rechargeable batteries.However, the unstable interface between lithium metal and electrolyte leads to the growth of dendrites,resulting in the low Coulombic efficiency and even the safety concerns. Herein, a rigid-flexible dual-layer vermiculite nanosheet(VN) based organic-inorganic hybrid film on lithium metal anode is proposed to suppress dendrite growth and relieve volume fluctuations. The inner mechanically robust VN layer(3 μm thick) enhances the mechanical properties of the protective layer, while the outer polymer(4 μm thick) can enhance the flexibility of the hybrid layer. The Li | Li symmetric cell with protected lithium shows an extended life of over 670 h. The full cell with Li anode protected by dual-layer interface exhibits a better capacity retention of 80% after 174 cycles in comparison to bare Li anode with 94 cycles.This study provides a novel approach and a significant step towards prolonging lifespan of lithium metal batteries.

Safer solid-state lithium metal batteries:Mechanisms and strategies

Solid-state batteries that employ solid-state electrolytes(SSEs)to replace routine liquid electrolytes are considered to be one of the most promising solutions for achieving high-safety lithium metal batteries.SSEs with high mechanical modulus,thermal stability,and non-flammability can not only inhibit the growth of lithium dendrites but also enhance the safety of lithium metal batteries.However,several internal materials/electrodes-related thermal hazards demonstrated by recent works show that solid-state lithium metal batteries(SSLMBs)are not impenetrable.Therefore,understanding the potential thermal hazards of SSLMBs is critical for their more secure and widespread applications.In this contribution,we provide a comprehensive overview of the thermal failure mechanism of SSLMBs from materials to devices.Also,strategies to improve the thermal safety performance of SSLMBs are included from the view of material enhancement,battery design,and external management.Consequently,the future directions are further provided.We hope that this work can shed bright insights into the path of constructing energy storage devices with high energy density and safety.

Higher-order polysulfides induced thermal runaway for 1.0 Ah lithium sulfur pouch cells

Comprehensive analyses on thermal runaway mechanisms are critically vital to achieve the safe lithium-sulfur(Li-S)batteries.The reactions between dissolved higher-order polysulfides and Li metal were found to be the origins for the thermal runaway of 1.0 Ah cycled Li-S pouch cells.16-cycle pouch cell indicates high safety,heating from 30 to 300 ℃ without thermal runaway,while 16-cycle pouch cell with additional electrolyte undergoes severe thermal runaway at 147.9 ℃,demonstrating the key roles of the electrolyte on the thermal safety of batteries.On the contrary,thermal runaway does not occur for 45-cycle pouch cell despite the addition of the electrolyte.It is found that the higher-order polysulfides(Li_(2)S_(x) ≥ 6)are discovered in 16-cycle electrolyte while the sulfur species in 45-cycle electrolyte are Li_(2)S_(x) ≤ 4.In addition,strong exothermic reactions are discovered between cycled Li and dissolved higher-order polysulfide(Li_(2)S_(6) and Li_(2)S_(8))at 153.0 ℃,driving the thermal runaway of cycled Li-S pouch cells.This work uncovers the potential safety risks of Li-S batteries and negative roles of the polysulfide shuttle for Li-S batteries from the safety view.

Life cycle safety issues of lithium metal batteries:A perspective

The rising lithium metal batteries(LMBs)demonstrate a huge potential for improving the utilization duration of energy storage devices due to high theoretical energy density.Benefiting from the designs in the electrolyte,interface,and lithium host,several attempts have been made in the commercial application of LMBs.However,the application of lithium anode introduces additional safety risks and potential catastrophic accidents due to the high activity of lithium metal and dendrite during the electrochemical cycles.A comprehensive understanding of challenges and design issues on the safety hazards of LMBs in life cycle management is imperative for safe and commercial applications of LMBs.This paper first reviews emerging key safety issues and promising corresponding enhancements of LMBs during their production,utilization,and recycling.The wet air instability of lithium metal anode and gas production during activation have undoubtedly become the most intractable problems in LMBs production.It is necessary to use spraying technology to build a good protection layer upon lithium metal anode.Then,the growth of lithium dendrites poses a higher challenge to the utilization of LMBs,which requires the design of better electrolyte,anode skeleton,and other strategies as well as the prediction of LMBs life through big data and other methods.As for LMBs recovery,it is of great significance to choose the solvent to effectively control the consumption rate and temperature of highly reactive lithium metal powder.At last,further appeals and improvements are proposed for inspiring more related research to push forward the commercial use of LMBs.

Deworming of stray dogs and wild canines with praziquantel-laced baits delivered by an unmanned aerial vehicle in areas highly endemic for echinococcosis in China

Background:Canines,the definitive hosts for the parasites causing alveolar(AE)and cystic echinococcosis(CE),are the main source of this infections playing the key role in the transmission.The ten-year mortality rate of AE is extremely high(94%)if the patients are not given sustained treatment.The aim of this field study is to explore the possibility of delivery of praziquantel-laced baits using unmanned aerial vehicles(UAVs)aimed at deworming wild canines in the endemic areas.Methods:UAVs were compared to manual bait delivery in the 1-km^(2)test areas followed by testing of canine faeces using an Echinococcus coproantigen ELISA test in the ensuing year.The outcomes of the two approaches were compared with respect to time of delivery and overall cost.Findings:Compared to manual bait delivery,delivery by UAVs saved up to 67%of the overall cost.Three times more staff was needed for the former approach compared to the latter and,time wise,UAV bait delivery saved 350%compared to manual bait delivery on average.With regard to investment needed,the use of UAVs showed an efficiency 2.5 times better than manual bait delivery.Compared to the area served by UAVs,the average positive rate for the canine faecal samples was more than 38%higher in the area served manually.Conclusion:The technique of bait delivery with praziquantel using UAVs for canine deworming has a strong potential with regard to savings of manpower,time and overall cost in areas highly endemic for echinococcosis.

Dendrite-accelerated thermal runaway mechanisms of lithium metal pouch batteries

High-energy-density lithium metal batteries(LMBs)are widely accepted as promising next-generation energy storage systems.However,the safety features of practical LMBs are rarely explored quantitatively.Herein,the thermal runaway behaviors of a 3.26 Ah(343 Wh kg^(−1))Li|LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)pouch cell in the whole life cycle are quantitatively investigated by extended volume-accelerating rate calorimetry and differential scanning calorimetry.By thermal failure analyses on pristine cell with fresh Li metal,activated cell with once plated dendrites,and 20-cycled cell with large quantities of dendrites and dead Li,dendrite-accelerated thermal runaway mechanisms including reaction sequence and heat release contribution are reached.Suppressing dendrite growth and reducing the reactivity between Li metal anode and electrolyte at high temperature are effective strategies to enhance the safety performance of LMBs.These findings can largely enhance the understanding on the thermal runaway behaviors of Li metal pouch cells in practical working conditions.

Mechanism understanding for stripping electrochemistry of Li metal anode

The pursuit of sustainable energy has a great request for advanced energy stor-age devices.Lithium metal batteries are regarded as a potential electrochemi-cal storage system because of the extremely high capacity and the most nega-tive electrochemical potential of lithium metal anode.Dead lithium formed in the stripping process significantly contributes to the low efficiency and short lifespan of rechargeable lithium metal batteries.This review displays a critical review on the current research status about the stripping electrochemistry of lithium metal anode.The significance of stripping process to a robust lithium metal anode is emphasized.The stripping models in different electrochemical scenarios are discussed.Specific attention is paid to the understanding for the electrochemical principles of atom diffusion,electrochemical reaction,ion dif-fusion in solid electrolyte interphase(SEI),and electron transfer with the pur-pose to strengthen the insights into the behavior of lithium electrode stripping.The factors affecting stripping processes and corresponding solutions are sum-marized and categorized as follows:surface physics,SEI,operational and exter-nal factors.This review affords fresh insights to explore the lithium anode and design robust lithium metal batteries based on the comprehensive understand-ing of the stripping electrochemistry.

Protection by the gross saponins of Tribulus terrestris against cerebral ischemic injury in rats involves the NF-κB pathway

The aim of this study was to investigate whether the gross saponins of Tribulus terrestris(GSTT),a traditional Chinese herbal medicine,have neuroprotective effects on rats subjected to middle cerebral artery occlusion(MCAO),through nuclear factor-κB(NF-κB)pathway and inflammatory mediators.Cerebral ischemia was produced by MCAO in either untreated(control)or GSTT-pretreated rats,and the animals were examined for infarct volume,cerebral edema,neuro-behavioral abnormality and pathological changes.Meanwhile,the expression of NF-kB protein in brain tissue was analyzed on Western blots and the serum levels of TNF-α and IL-1 were determined by ELISA.The experimental results demonstrated that,compared with the control MCAO group,GSTT-pretreated MCAO group had significantly reduced infarct volume,brain edema and neuro-behavioral abnormality,and lesser degree of pathologic changes in the brain,as well as had lower levels of serum TNF-α and IL-1β,and higher levels of brain NF-κB(Po0.05).Furthermore,treatment with an NF-κB inhibitor pyrrolidine dithiocarbamate(PDTC)abolished the protective effects of GSTT against MCAO-induced cerebral ischemic injury.These results indicated that GSTT’s ability to protect against cerebral ischemic injury was mediated through the NF-κB signaling pathway,and that GSTT may act through inhibition of the production of inflammatory mediators.

A remote management system for control and surveillance of echinococcosis:design and implementation based on internet of things

Background:As a neglected cross-species parasitic disease transmitted between canines and livestock,echinococcosis remains a global public health concern with a heavy disease burden.In China,especially in the epidemic pastoral communities on the Qinghai-Tibet Plateau,the harsh climate,low socio-economic status,poor overall hygiene,and remote and insufficient access to all owned dogs exacerbate the difficulty in implementing the ambitious control programme for echinococcosis.We aimed to design and implement a remote management system(RMS)based on internet of things(loT)for control and surveillance of echinococcosis by combining deworming devices to realise long-distance smart deworming control,smooth statistical analysis and result display.New methods and tools are urgently needed to increase the deworming coverage and frequency,promote real-time scientific surveillance,and prevent transmission of echinococcosis in remoted transmission areas.

Vortex-pair states in spin-orbit-coupled Bose-Einstein condensates with coherent coupling

Three types of vortex-pair are identified in two-component Bose-Einstein condensates （BEC） of dif- ferent kinds of spin-orbit coupling. One type holds the two vortices in one component of the two- component condensates. Both the other two types hold a vortex in each component of the two- component condensates, and exhibit meron-pair textures that have either null or unit topological charge, respectively. The cores of the two vortices are connected by a string of the relative phase jump. These vortex pairs can be generated from a vortex-free wave packet by incorporating different non- Abelian gauge field into the BEC. When a Rabi coupling is introduced, the distance between the two cores is effectively controlled by the Rabi coupling strength and a transition of vortex configurations is observed.