Lithium metal batteries(LMBs)are considered the ideal next-generation high-energy-density systems,capable of surpassing the performance of lithium-ion batteries(LIBs).However,LMBs suffer from issues such as irreversib...Lithium metal batteries(LMBs)are considered the ideal next-generation high-energy-density systems,capable of surpassing the performance of lithium-ion batteries(LIBs).However,LMBs suffer from issues such as irreversible Li deposition/stripping,dendrite growth and significant volume fluctuations.Here,we use doctor blade coating to precisely control the loading of the bulk hard carbon(BHC)host with closed nanopores on carbon-coated copper(CCu)foil to achieve optimal cycling stability and rate performance for Li metal and anode-free battery systems.Through ex/in-situ techniques,we demonstrate that the BHC host induces a continuous intercalation-deposition mechanism,where the pre-lithiated BHC(preliBHC)phase,formed by Li+intercalation,improves Li affinity,accelerates Li+transport,and reduces nucleation overpotential,resulting in uniform Li deposition and effectively suppressing dendrite growth.Furthermore,these characterizations reveal that irreversible Li deintercalation from graphite layers is a key factor leading to the low initial Coulombic efficiency(ICE).Consequently,when coupled with a LiFePO_(4)cathode,the BHC-based full cell retains 96.3% of its capacity after 210 cycles at 1 C,demonstrating exceptional cycling stability.Notably,at-20℃,the full cell maintains 94.2% capacity retention after 60 cycles.These findings deepen the understanding of regulating Li metal deposition mechanisms and offer valuable insights into designing Li metal hosts for improved cycle life and high-rate performance.展开更多
Metallic Li is a promising anode material for high energy density batteries but it suffers from poor stability and formation of unsafe dendrites. Previous studies demonstrated that 3 D metal foams are able to improve ...Metallic Li is a promising anode material for high energy density batteries but it suffers from poor stability and formation of unsafe dendrites. Previous studies demonstrated that 3 D metal foams are able to improve the stability of Li metal but the properties of these foams are inherently limited. Here we report a facile surface modification approach via magnetron sputtering of mixed oxides that effectively modulate the properties of Cu foams for supporting Li metal with remarkable stability. We discovered that hybrid Li anodes with Li metal thermally infused to aluminum-zinc oxides(AZO) coated Cu foams have significantly improved stability and reactivity compared with pristine Li foils and Li infused to unmodified Cu foams. Full cells assembled with a Li Fe PO4 cathode and a hybrid anode maintained low and stable charge-transfer resistance(<50) during 500 cycles in carbonate electrolytes, and exhibited superior rate capability(~100 m Ah g-1 at 20 C) along with better electrochemical reversibility and surface stability. The AZO modified Cu foams had superior mechanical strength and afforded the hybrid anodes with minimized volume change without the formation of dendrites during battery cycling. The rational construction of surface architecture to precisely control Li plating and stripping may have great implications for the practical applications of Li metal batteries.展开更多
Lithium sulfur batteries are regarded as a promising candidate for high-energy-density energy storage devices.However,the lithium metal anode in lithium-sulfur batteries encounters the problem of lithium dendrites and...Lithium sulfur batteries are regarded as a promising candidate for high-energy-density energy storage devices.However,the lithium metal anode in lithium-sulfur batteries encounters the problem of lithium dendrites and lithium metal consumption caused by polysulfide corrosion.Herein we design a dualfunction PMMA/PPC/LiNO3composite as an artificial solid electrolyte interphase(PMCN-SEI)to protect Li metal anode.This SEI offers multiple sites of C=O for polysulfide anchoring to constrain corrosion of Li metal anode.The lithiated polymer group and Li3N in PMCN-SEI can homogenize lithium-ion deposition behavior to achieve a dendrite-free anode.As a result,the PMCN-SEI protected Li metal anode enables the Li||Li symmetric batteries to maintain over 300 cycles(1300 h)at a capacity of 5 m Ah cm^(-2),corresponding to a cumulative capacity of 3.25 Ah cm^(-2).Moreover,Li-S batteries assembled with 20μm of Li metal anode(N/P=1.67)still deliver an initial capacity of 1166 m A h g-1at 0.5C.Hence,introducing polycarbonate polymer/inorganic composite SEI on Li provides a new solution for achieving the high energy density of Li-S batteries.展开更多
Constructing a smart polymer film with favorable lithium(Li)transport capability and mechanical flexibility for suppressing Li dendrite growth is an effective strategy.Unfortunately,the porosity and the swelling of th...Constructing a smart polymer film with favorable lithium(Li)transport capability and mechanical flexibility for suppressing Li dendrite growth is an effective strategy.Unfortunately,the porosity and the swelling of the polymer membrane cannot completely prevent liquid electrolyte from sweeping through the artificial protection film,severely deteriorating the cyclic performance.Herein,we propose a defectfree hybrid film that consists of Li+conductive lithium polyacrylate(LiPAA)polymer interface layer and Li-Zn alloy patch to tackle the critical problems of traditional polymer composite passivation film.The pinhole leaks of the polymer matrix are self-filled by Li-Zn alloy patches,enhancing the integrity of LiPAA film.Consequently,a defect-free hybrid film is nailed flat against the Li metal anode,exhibiting extraordinary stability in the liquid electrolyte and enabling perfect protection effect.This facile strategy produces a promising anode for next generation Li batteries.展开更多
In this paper, a new limited memory quasi-Newton method is proposed and developed for solving large-scale linearly equality-constrained nonlinear programming problems. In every iteration, a linear equation subproblem ...In this paper, a new limited memory quasi-Newton method is proposed and developed for solving large-scale linearly equality-constrained nonlinear programming problems. In every iteration, a linear equation subproblem is solved by using the scaled conjugate gradient method. A truncated solution of the subproblem is determined so that computation is decreased. The technique of limited memory is used to update the approximated inverse Hessian matrix of the Lagrangian function. Hence, the new method is able to handle large dense problems. The convergence of the method is analyzed and numerical results are reported.展开更多
基金supported by the National Key Research and Development Program of China(2022YFE0109400)Leading Edge Technology of Jiangsu Province(BK20220009,BK20232022)+1 种基金Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)Center for Microscopy and Analysis at Nanjing University of Aeronautics and Astronautics。
文摘Lithium metal batteries(LMBs)are considered the ideal next-generation high-energy-density systems,capable of surpassing the performance of lithium-ion batteries(LIBs).However,LMBs suffer from issues such as irreversible Li deposition/stripping,dendrite growth and significant volume fluctuations.Here,we use doctor blade coating to precisely control the loading of the bulk hard carbon(BHC)host with closed nanopores on carbon-coated copper(CCu)foil to achieve optimal cycling stability and rate performance for Li metal and anode-free battery systems.Through ex/in-situ techniques,we demonstrate that the BHC host induces a continuous intercalation-deposition mechanism,where the pre-lithiated BHC(preliBHC)phase,formed by Li+intercalation,improves Li affinity,accelerates Li+transport,and reduces nucleation overpotential,resulting in uniform Li deposition and effectively suppressing dendrite growth.Furthermore,these characterizations reveal that irreversible Li deintercalation from graphite layers is a key factor leading to the low initial Coulombic efficiency(ICE).Consequently,when coupled with a LiFePO_(4)cathode,the BHC-based full cell retains 96.3% of its capacity after 210 cycles at 1 C,demonstrating exceptional cycling stability.Notably,at-20℃,the full cell maintains 94.2% capacity retention after 60 cycles.These findings deepen the understanding of regulating Li metal deposition mechanisms and offer valuable insights into designing Li metal hosts for improved cycle life and high-rate performance.
基金The financial supports of the National Natural Science Foundation of China(Grant Nos.51572060,51702067 and 51671074)Special Financial Grant from the China Postdoctoral Science Foundation(No.2017T100239)+1 种基金General Financial Grant from the China Postdoctoral Science Foundation(No.2016M590279)the startup grants from Northern Illinois University。
文摘Metallic Li is a promising anode material for high energy density batteries but it suffers from poor stability and formation of unsafe dendrites. Previous studies demonstrated that 3 D metal foams are able to improve the stability of Li metal but the properties of these foams are inherently limited. Here we report a facile surface modification approach via magnetron sputtering of mixed oxides that effectively modulate the properties of Cu foams for supporting Li metal with remarkable stability. We discovered that hybrid Li anodes with Li metal thermally infused to aluminum-zinc oxides(AZO) coated Cu foams have significantly improved stability and reactivity compared with pristine Li foils and Li infused to unmodified Cu foams. Full cells assembled with a Li Fe PO4 cathode and a hybrid anode maintained low and stable charge-transfer resistance(<50) during 500 cycles in carbonate electrolytes, and exhibited superior rate capability(~100 m Ah g-1 at 20 C) along with better electrochemical reversibility and surface stability. The AZO modified Cu foams had superior mechanical strength and afforded the hybrid anodes with minimized volume change without the formation of dendrites during battery cycling. The rational construction of surface architecture to precisely control Li plating and stripping may have great implications for the practical applications of Li metal batteries.
基金supported by the Jilin Province Science and Technology Department Program(YDZJ202201ZYTS304)the Science and Technology Project of Jilin Provincial Education Department(JJKH20220428KJ)+3 种基金the Jilin Province Science and Technology Department Program(YDZJ202101ZYTS047)the National Natural Science Foundation of China(21905110,21905041,22279045,22102020)the Special foundation of Jilin Province Industrial Technology Research and Development(2019C042)the Fundamental Research Funds for the Central Universities(2412020FZ008)。
文摘Lithium sulfur batteries are regarded as a promising candidate for high-energy-density energy storage devices.However,the lithium metal anode in lithium-sulfur batteries encounters the problem of lithium dendrites and lithium metal consumption caused by polysulfide corrosion.Herein we design a dualfunction PMMA/PPC/LiNO3composite as an artificial solid electrolyte interphase(PMCN-SEI)to protect Li metal anode.This SEI offers multiple sites of C=O for polysulfide anchoring to constrain corrosion of Li metal anode.The lithiated polymer group and Li3N in PMCN-SEI can homogenize lithium-ion deposition behavior to achieve a dendrite-free anode.As a result,the PMCN-SEI protected Li metal anode enables the Li||Li symmetric batteries to maintain over 300 cycles(1300 h)at a capacity of 5 m Ah cm^(-2),corresponding to a cumulative capacity of 3.25 Ah cm^(-2).Moreover,Li-S batteries assembled with 20μm of Li metal anode(N/P=1.67)still deliver an initial capacity of 1166 m A h g-1at 0.5C.Hence,introducing polycarbonate polymer/inorganic composite SEI on Li provides a new solution for achieving the high energy density of Li-S batteries.
基金partly supported by the National Natural Science Foundation of China(Nos.22379019 and 52172184)the Science and Technology Department of Sichuan Province of China(No.24GJHZ0444)and S&T Special Program of Huzhou(No.2023GZ03)。
文摘Constructing a smart polymer film with favorable lithium(Li)transport capability and mechanical flexibility for suppressing Li dendrite growth is an effective strategy.Unfortunately,the porosity and the swelling of the polymer membrane cannot completely prevent liquid electrolyte from sweeping through the artificial protection film,severely deteriorating the cyclic performance.Herein,we propose a defectfree hybrid film that consists of Li+conductive lithium polyacrylate(LiPAA)polymer interface layer and Li-Zn alloy patch to tackle the critical problems of traditional polymer composite passivation film.The pinhole leaks of the polymer matrix are self-filled by Li-Zn alloy patches,enhancing the integrity of LiPAA film.Consequently,a defect-free hybrid film is nailed flat against the Li metal anode,exhibiting extraordinary stability in the liquid electrolyte and enabling perfect protection effect.This facile strategy produces a promising anode for next generation Li batteries.
基金This research is supported by the National Natural Science Foundation of China, LSEC of CAS in Beijingand Natural Science Foun
文摘In this paper, a new limited memory quasi-Newton method is proposed and developed for solving large-scale linearly equality-constrained nonlinear programming problems. In every iteration, a linear equation subproblem is solved by using the scaled conjugate gradient method. A truncated solution of the subproblem is determined so that computation is decreased. The technique of limited memory is used to update the approximated inverse Hessian matrix of the Lagrangian function. Hence, the new method is able to handle large dense problems. The convergence of the method is analyzed and numerical results are reported.
