Chloro-propylene sulfite （CIPS） was employed as electrolyte additive of Li/S batteries for the first time. Linear potential sweep test showed that the CIPS keeps high electrochemical stability even under the voltage...Chloro-propylene sulfite （CIPS） was employed as electrolyte additive of Li/S batteries for the first time. Linear potential sweep test showed that the CIPS keeps high electrochemical stability even under the voltage of 5.0V. Being used as electrolyte additive in Li/S batteries, CIPS displayed an excellent property for self-discharge prohibition. With CIPS additive the Li/S cells initial discharge capacity was 856.2 mAh·g^-1 and 830.8 mAh·g^-1 at the current density of 15 mA.g and 30 mA·g^-1 , after 30 cycles the discharge capacities were contained at as high as 753.8 mAh.g and 715.6 mAh·g^-1. By means of infrared spectra, TG/DTA experiment and element conten analysis the speculated reason of CIPS＇s novel function as additive was proposed.展开更多
Sluggish kinetics of lithium/sulfur(Li/S)conversion chemistry and the ion channels formation in the cathode is still a bottleneck for developing future Li/S batteries with high-rate,long-cycling and high-energy.Here,a...Sluggish kinetics of lithium/sulfur(Li/S)conversion chemistry and the ion channels formation in the cathode is still a bottleneck for developing future Li/S batteries with high-rate,long-cycling and high-energy.Here,a rational cathode structure design of an oxygen(O)and nitrogen(N)tailoring carbon fiber aerogel(OCNF)as a host material integrated with platinum(Pt)electrocatalysis interface is employed to regulate Li/S conversion chemistry and ion channel.The Pt nanoparticles were uniformly sprayed onto the S surface to construct the electrocatalysis interface(Pt/S/OCNF)for generating ion channels to promote the effective penetration of electrolyte into the cathode.This Pt/S/OCNF gives the cathode a high sulfur utilization of 77.5%,an excellent rate capacity of 813.2 m Ah/g(2 C),and an outstanding long-cycling performance with a capacitance retention of 82.6%and a decay of 0.086%per cycle after 200 cycles at 0.5 C.Density functional theory(DFT)calculations reveal that the Pt electrocatalysis interface makes the cathode a high density of state(DOS)at Fermi level to facilitate the electrical conductivity,charge transfer kinetics and electrocatalysis to accelerate the lithium polysulfides(LiPSs)electrochemical conversion.Furthermore,the unique chemisorption structure and adsorption ability of Li2Sn(n=1,2,4,6,8)and S8on OCNF are attributed to the bridging effects of interfacial Pt and the bonding of N-Li.The Pt electrocatalysis interface combined with the unique 3D hierarchical porous structure and abundant functional active sites at OCNF guarantee strong adsorption confinement,fast Li/S electrocatalytic conversion and unblocked ion channels for electrolyte permeation in cathode.展开更多
Owing to their low cost,high energy densities,and superior performance compared with that of Li-ion batteries,Li–S batteries have been recognized as very promising next-generation batteries.However,the commercializat...Owing to their low cost,high energy densities,and superior performance compared with that of Li-ion batteries,Li–S batteries have been recognized as very promising next-generation batteries.However,the commercialization of Li–S batteries has been hindered by the insulation of sulfur,significant volume expansion,shuttling of dissolved lithium polysulfides(Li PSs),and more importantly,sluggish conversion of polysulfide intermediates.To overcome these problems,a state-of-the-art strategy is to use sulfur host materials that feature chemical adsorption and electrocatalytic capabilities for Li PS species.In this review,we comprehensively illustrate the latest progress on the rational design and controllable fabrication of materials with chemical adsorbing and binding capabilities for Li PSs and electrocatalytic activities that allow them to accelerate the conversion of Li PSs for Li–S batteries.Moreover,the current essential challenges encountered when designing these materials are summarized,and possible solutions are proposed.We hope that this review could provide some strategies and theoretical guidance for developing novel chemical anchoring and electrocatalytic materials for high-performance Li–S batteries.展开更多
Use of metallic Li anode raises serious concerns on the safety and operational performance of Li-S batteries due to uncontrolled hazard of Li dendrite formation, which is difficultly eliminated as long as the metallic...Use of metallic Li anode raises serious concerns on the safety and operational performance of Li-S batteries due to uncontrolled hazard of Li dendrite formation, which is difficultly eliminated as long as the metallic Li exists in the cells. Pairing lithium sulfide (Li2S) cathode with currently available metallic Lifree high-capacity anodes offers an alternative solution to this challenge. However, the performance of Li2S cathode is primarily restricted by high activation barrier upon initial charge, low active mass utilization and sluggish redox kinetics. Herein, a MXene-induced multifunctional collaborative interface is proposed to afford superb activity towards redox solid-liquid/liquid-liquid phase transformation, strong chemisorption, high conductivity and fast ionic/charge transport in high Li2S loading cathode. Applying collaborative interface effectively reduces initial voltage barrier of Li2S activation and regulates the kinetic behavior of redox polysulfide conversion. Therefore, stable operation of additive-free Li2S cathode with high areal capacities at high Li2S loading up to 9 mg cm^-2 can be achieved with less sacrifice of high capacity and rate capability in Li-S batteries. Rechargeable metallic Li-free batteries are successfully constructed by pairing this high-performance Li2S cathode with high-capacity metal oxide anodes, which delivers superior energy density to current Li-ion batteries.展开更多
采用电化学法,在硫电极表面沉积一层聚(3,4–乙烯二氧噻吩)薄膜,并研究了相关锂–硫(Li-S)电池的电化学性能。结果表明,这种简单的电化学方法容易实现在整个硫电极表面制备一层致密、均匀、厚度可控的导电高分子薄膜,并且显著提高Li-S...采用电化学法,在硫电极表面沉积一层聚(3,4–乙烯二氧噻吩)薄膜,并研究了相关锂–硫(Li-S)电池的电化学性能。结果表明,这种简单的电化学方法容易实现在整个硫电极表面制备一层致密、均匀、厚度可控的导电高分子薄膜,并且显著提高Li-S电池的循环稳定性。其中,薄膜电沉积500次时,其改性硫电极的初始放电比容量为955 m Ah/g,在放电电流密度为900 m A/g时,800次充放电循环后比容量为590 m Ah/g,即每个循环的容量损失率仅为0.047%。展开更多
文摘Chloro-propylene sulfite （CIPS） was employed as electrolyte additive of Li/S batteries for the first time. Linear potential sweep test showed that the CIPS keeps high electrochemical stability even under the voltage of 5.0V. Being used as electrolyte additive in Li/S batteries, CIPS displayed an excellent property for self-discharge prohibition. With CIPS additive the Li/S cells initial discharge capacity was 856.2 mAh·g^-1 and 830.8 mAh·g^-1 at the current density of 15 mA.g and 30 mA·g^-1 , after 30 cycles the discharge capacities were contained at as high as 753.8 mAh.g and 715.6 mAh·g^-1. By means of infrared spectra, TG/DTA experiment and element conten analysis the speculated reason of CIPS＇s novel function as additive was proposed.
基金funding support from National Key R&D Program of China(No.2016YFB0100100)The National Natural Science Foundation of China(Nos.21961024,21961025,21433013,U1832218)+5 种基金Inner Mongolia Natural Science Foundation(No.2018JQ05)Supported by Incentive Funding from Nano Innovation Institute(NII)of Inner Mongolia University for Nationalities(IMUN)Inner Mongolia Autonomous Region Funding Project for Science&Technology Achievement Transformation(No.CGZH2018156)Inner Mongolia Autonomous Region Incentive Funding Guided Project for Science&Technology Innovation(2016)Inner Mongolia Autonomous Region Science&Technology Planning Project for Applied Technology Research and Development(No.2019GG261)Tongliao Funding Project for Application Technology Research&Development(2017)。
文摘Sluggish kinetics of lithium/sulfur(Li/S)conversion chemistry and the ion channels formation in the cathode is still a bottleneck for developing future Li/S batteries with high-rate,long-cycling and high-energy.Here,a rational cathode structure design of an oxygen(O)and nitrogen(N)tailoring carbon fiber aerogel(OCNF)as a host material integrated with platinum(Pt)electrocatalysis interface is employed to regulate Li/S conversion chemistry and ion channel.The Pt nanoparticles were uniformly sprayed onto the S surface to construct the electrocatalysis interface(Pt/S/OCNF)for generating ion channels to promote the effective penetration of electrolyte into the cathode.This Pt/S/OCNF gives the cathode a high sulfur utilization of 77.5%,an excellent rate capacity of 813.2 m Ah/g(2 C),and an outstanding long-cycling performance with a capacitance retention of 82.6%and a decay of 0.086%per cycle after 200 cycles at 0.5 C.Density functional theory(DFT)calculations reveal that the Pt electrocatalysis interface makes the cathode a high density of state(DOS)at Fermi level to facilitate the electrical conductivity,charge transfer kinetics and electrocatalysis to accelerate the lithium polysulfides(LiPSs)electrochemical conversion.Furthermore,the unique chemisorption structure and adsorption ability of Li2Sn(n=1,2,4,6,8)and S8on OCNF are attributed to the bridging effects of interfacial Pt and the bonding of N-Li.The Pt electrocatalysis interface combined with the unique 3D hierarchical porous structure and abundant functional active sites at OCNF guarantee strong adsorption confinement,fast Li/S electrocatalytic conversion and unblocked ion channels for electrolyte permeation in cathode.
基金supported by the National Natural Science Foundation of China(No.51403094)Program of Liaoning Education Department of China(No.LJ2017FBL002)Australian Research Council through the Discovery Early Career Researcher Award(DECRA,No.DE170100871)Program.
文摘Owing to their low cost,high energy densities,and superior performance compared with that of Li-ion batteries,Li–S batteries have been recognized as very promising next-generation batteries.However,the commercialization of Li–S batteries has been hindered by the insulation of sulfur,significant volume expansion,shuttling of dissolved lithium polysulfides(Li PSs),and more importantly,sluggish conversion of polysulfide intermediates.To overcome these problems,a state-of-the-art strategy is to use sulfur host materials that feature chemical adsorption and electrocatalytic capabilities for Li PS species.In this review,we comprehensively illustrate the latest progress on the rational design and controllable fabrication of materials with chemical adsorbing and binding capabilities for Li PSs and electrocatalytic activities that allow them to accelerate the conversion of Li PSs for Li–S batteries.Moreover,the current essential challenges encountered when designing these materials are summarized,and possible solutions are proposed.We hope that this review could provide some strategies and theoretical guidance for developing novel chemical anchoring and electrocatalytic materials for high-performance Li–S batteries.
基金supported by the National Natural Science Foundation of China (NSFC, No. 51522203, 51772040)Fok Ying Tung Education Foundation (No. 151047)+2 种基金the Recruitment Program of Global Youth ExpertsXinghai Scholarship of Dalian University of Technologythe Fundamental Research Funds for the Central Universities (No. DUT18LAB19)
文摘Use of metallic Li anode raises serious concerns on the safety and operational performance of Li-S batteries due to uncontrolled hazard of Li dendrite formation, which is difficultly eliminated as long as the metallic Li exists in the cells. Pairing lithium sulfide (Li2S) cathode with currently available metallic Lifree high-capacity anodes offers an alternative solution to this challenge. However, the performance of Li2S cathode is primarily restricted by high activation barrier upon initial charge, low active mass utilization and sluggish redox kinetics. Herein, a MXene-induced multifunctional collaborative interface is proposed to afford superb activity towards redox solid-liquid/liquid-liquid phase transformation, strong chemisorption, high conductivity and fast ionic/charge transport in high Li2S loading cathode. Applying collaborative interface effectively reduces initial voltage barrier of Li2S activation and regulates the kinetic behavior of redox polysulfide conversion. Therefore, stable operation of additive-free Li2S cathode with high areal capacities at high Li2S loading up to 9 mg cm^-2 can be achieved with less sacrifice of high capacity and rate capability in Li-S batteries. Rechargeable metallic Li-free batteries are successfully constructed by pairing this high-performance Li2S cathode with high-capacity metal oxide anodes, which delivers superior energy density to current Li-ion batteries.
文摘采用电化学法,在硫电极表面沉积一层聚(3,4–乙烯二氧噻吩)薄膜,并研究了相关锂–硫(Li-S)电池的电化学性能。结果表明,这种简单的电化学方法容易实现在整个硫电极表面制备一层致密、均匀、厚度可控的导电高分子薄膜,并且显著提高Li-S电池的循环稳定性。其中,薄膜电沉积500次时,其改性硫电极的初始放电比容量为955 m Ah/g,在放电电流密度为900 m A/g时,800次充放电循环后比容量为590 m Ah/g,即每个循环的容量损失率仅为0.047%。
