Lithium metal has been regarded as the ultimate anode for next-generation rechargeable batteries with high energy density.However,its high reactivity and dendrite growth seriously limit its commercial application,whic...Lithium metal has been regarded as the ultimate anode for next-generation rechargeable batteries with high energy density.However,its high reactivity and dendrite growth seriously limit its commercial application,which can be well addressed by realizing uniform Li deposition.Here,we report a facile and scalable one-step vulcanization method to modify commercial Cu foil with lithophilic Cu2S.The in situ formed Cu2S layer can not only promote the homogeneous deposition of Li via its lithophilic nature,but also benefit the formation of a stable solid-electrolyte interphase during initial activation.The Cu2S-modified Cu current collector realizes dendrite-free Li plating/stripping and thus exhibits stable cycling performance with a high Coulombic efficiency,even with a large capacity of 4 mA h cm^-2.A full-cell consisting of a Cu2S/Cu-Li anode and a LiFePO4 cathode exhibits greatly improved cycling stability and enhanced Coulombic efficiency,demonstrating the effectiveness and practicability of the proposed Cu2S/Cu foil in the field of rechargeable Li metal batteries.展开更多
The concentration difference in the near-surface region of lithium metal is the main cause of lithium dendrite growth.Resolving this issue will be key to achieving high-performance lithium metal batteries(LMBs).Herein...The concentration difference in the near-surface region of lithium metal is the main cause of lithium dendrite growth.Resolving this issue will be key to achieving high-performance lithium metal batteries(LMBs).Herein,we construct a lithium nitrate(LiNO_(3))-implanted electroactiveβphase polyvinylidene fluoride-co-hexafluoropropylene(PVDF-HFP)crystalline polymorph layer(PHL).The electronegatively charged polymer chains attain lithium ions on the surface to form lithium-ion charged channels.These channels act as reservoirs to sustainably release Li ions to recompense the ionic flux of electrolytes,decreasing the growth of lithium dendrites.The stretched molecular channels can also accelerate the transport of Li ions.The combined effects enable a high Coulombic efficiency of 97.0%for 250 cycles in lithium(Li)||copper(Cu)cell and a stable symmetric plating/stripping behavior over 2000 h at 3 mA cm^(-2)with ultrahigh Li utilization of 50%.Furthermore,the full cell coupled with PHL-Cu@Li anode and Li Fe PO_(4) cathode exhibits long-term cycle stability with high-capacity retention of 95.9%after 900 cycles.Impressively,the full cell paired with LiNi_(0.87)Co_(0.1)Mn_(0.03)O_(2)maintains a discharge capacity of 170.0 mAh g^(-1)with a capacity retention of 84.3%after 100 cycles even under harsh condition of ultralow N/P ratio of 0.83.This facile strategy will widen the potential application of LiNO_(3)in ester-based electrolyte for practical high-voltage LMBs.展开更多
The metallic lithium(Li)is considered as the most promising anode material for high-e nergy batteries.Nevertheless,the uncon trollable growth of Li den drite and un stable electrolyte/electrode in terface still hin de...The metallic lithium(Li)is considered as the most promising anode material for high-e nergy batteries.Nevertheless,the uncon trollable growth of Li den drite and un stable electrolyte/electrode in terface still hin der the developme nt of Li-based battery.In this work,a no vel strategy has been proposed to stabilize Li anode by in-situ polymerizing polypyrrole(PPy)layer on Ni foam(PPy@Ni foam)as an artificial protective layer.The PPy protective layer can effectively decrease the contact between Li metal and electrolyte during cycling.In addition,the morphology characterization shows that the PPy layer can help the even Li deposition undemeath the layer,leading to a dendrite-free Li anode.As a result,when deposited 2 mAh-cm-2 Li metal,the PPy@Ni foam can keep stable Coulombic efficiency(99%)during nearly 250 cycles,much better than the pure Ni foam(100 cycles).Even in the case of the Li capacity of 10 mAh-cm-2,the stable cycling performance for 60 cycles can still be achieved.Furthermore,when assembled with LiFePO4 material as the cathode for a full cell,the PPy@Ni foam can keep high capacity retention of 85.5%at 500 cycles.In our work,we provide a simple and effective method to enhanee the electrochemical performances of Li metal-based batteries,and reveal a new avenue to design three-dimensional(3D)metallic curre nt collector for protecting the Li metal ano de.展开更多
Lithium metal batteries are strongly considered as one of the most promising candidates for nextgeneration high-performance battery systems.However,the uncontrollable growth of lithium dendrites and the highly reactiv...Lithium metal batteries are strongly considered as one of the most promising candidates for nextgeneration high-performance battery systems.However,the uncontrollable growth of lithium dendrites and the highly reactive lithium metal result in the severe safety risks and the short lifespan for highenergy-density rechargeable batteries.Here,we demonstrate a hydrophobic and ionically conductive ethylene-vinyl acetate(EVA)copolymer layer can not only endow lithium metal anodes with an air-stable and anti-water surface,but also efficiently suppress the lithium-dendrites growth during the electrochemical cycling process.Therefore,the introduction of the EVA copolymer as a bifunctional protection layer simultaneously improves the anti-water/air performance and electrochemical cycling stability of lithium metal anode.展开更多
Cold metal transfer plus pulse(C+P)arc was applied in the additive manufacturing of 4043 Al alloy parts.Parameters in the manufacturing of the parts were investigated.The properties and microstructure of the parts wer...Cold metal transfer plus pulse(C+P)arc was applied in the additive manufacturing of 4043 Al alloy parts.Parameters in the manufacturing of the parts were investigated.The properties and microstructure of the parts were also characterized.Experimental results showed that welding at a speed of 8 mm/s and a wire feeding speed of 4.0 m/min was suitable to manufacture thin-walled parts,and the reciprocating scanning method could be adopted to manufacture thick-walled parts.The thin-walled parts of the C+P mode had fewer pores than those of the cold metal transfer(CMT)mode.The thin-and thick-walled parts of the C+P mode showed maximum tensile strengths of 172 and 178 MPa,respectively.Hardness decreased at the interface and in the coarse dendrite and increased in the refined grain area.展开更多
A series of alkali metal salts doped pluronic block copolymer F127 were used as electron injection/transport layers (ETLs) for polymer light-emitting diodes with poly[2-(4-(3′,7′-dimethyloctyloxy)-phenyl)-p-phenylen...A series of alkali metal salts doped pluronic block copolymer F127 were used as electron injection/transport layers (ETLs) for polymer light-emitting diodes with poly[2-(4-(3′,7′-dimethyloctyloxy)-phenyl)-p-phenylenevinylene] (P-PPV) as the emission layer. It was found that the electron transport capability of F127 can be effectively enhanced by doping with alkali metal salts. By using Li2CO3 (15%) doped F127 as ETL, the resulting device exhibited improved performance with a maximum luminous efficiency (LE) of 13.59 cd/A and a maximum brightness of 5529 cd/m2, while the device with undoped F127 as ETL only showed a maximum LE of 8.78 cd/A and a maximum brightness of 2952 cd/m2. The effects of the doping concentration, cations and anions of the alkali metal salts on the performance of the resulting devices were investigated. It was found that most of the alkali metal salt dopants can dramatically enhance the electron transport capability of F127 ETL and the performance of the resulting devices was greatly improved.展开更多
Although aqueous zinc ion hybrid capacitors have advantageous integration of batteries and supercapacitors,they still suffer from the inherent problems of dendrite growth and interfacial side reactions on Zn anodes.He...Although aqueous zinc ion hybrid capacitors have advantageous integration of batteries and supercapacitors,they still suffer from the inherent problems of dendrite growth and interfacial side reactions on Zn anodes.Herein,a universal fast zinc-ion diffusion layer on a three-dimensional(3 D)mesh structure model is demonstrated to effectively improve Zn plating/stripping reversibility.The fast ion diffusion alloy layer accelerates the Zn^(2+)migration in an orderly manner to homogenize Zn^(2+)flux and overcomes the defects of the commercial mesh substrate,effectively avoiding dendrite growth and side reactions.Consequently,the proof-of-concept silver-zinc alloy modified stainless steel mesh delivers superb reversibility with the high coulombic efficiency over 99.4%at 4 mA cm^(-2)after 1600 cycles and excellent reliability of over 830 h at 1 mA cm^(-2),Its feasibility is also evidenced in commercial zinc ion hybrid capacitors with activated carbon as the cathode.This work enriches the fundamental comprehension of fast zinc-ion diffusion layer combined with a 3 D substrate on the Zn deposition and opens a universal approach to design advanced host for Zn electrodes in zinc ion hybrid capacitors.展开更多
Potassium metal batteries(PMBs)have become a paramount alternative energy storage technology to lithium-ion batteries,due to their low cost and potential energy density.However,uncontrolled dendrite growth interferes ...Potassium metal batteries(PMBs)have become a paramount alternative energy storage technology to lithium-ion batteries,due to their low cost and potential energy density.However,uncontrolled dendrite growth interferes with the stability of the interfacial anode,leading to significant capacity degradation and safety hazards.Herein,a facile reactive prewetting strategy is proposed to discourage dendrite growth by constructing a functional KF/Znrich hybrid interface layer on K metal.The KF/Zn@K anode design functions like an interconnected paddy field,stabilizing the anode interface through the preferential redistribution of Kþflux/electrons,continuous transport paths,and enhanced transport dynamics.As anticipated,symmetrical batteries exhibit an extended cycling lifetime of over 2000 h,with reduced voltage hysteresis at 0.5 mA cm^(-2) and 0.5 mAh cm^(-2).Furthermore,when the KF/Zn@K anode is applied to full batteries coupled with PTCDA,a boosted reversible capacity of 61.6 mAh g1 at 5 C is present over 3000 cycles.This interfacial control creates rational possibilities for constructing highefficiency,stable K metal anodes.展开更多
OLED(Organic Light-Emitting Diode)屏幕COF(Chip on Film)连接过渡区的金属层在模组弯折阶段和可靠性验证阶段容易发生断裂,导致屏幕显示异常。本文采用试验设计(Design of Experiment,DOE)方法,以弯折成型状态和可靠性状态下的金属...OLED(Organic Light-Emitting Diode)屏幕COF(Chip on Film)连接过渡区的金属层在模组弯折阶段和可靠性验证阶段容易发生断裂,导致屏幕显示异常。本文采用试验设计(Design of Experiment,DOE)方法,以弯折成型状态和可靠性状态下的金属层应力最小作为试验指标,以泡棉厚度、泡棉偏移、金属包覆层(Metal Cover Layer,MCL)厚度和U型膜偏移作为影响因子,设计L9(34)正交试验方案,使用有限元方法对9组试验方案进行数值模拟和分析,并进行弯折成型和可靠性状态下的试验验证,最终获得了最优组合方案。有限元方法和试验结果表明,U型膜贴附偏移量对COF区的金属层弯折应力的影响最大,其次是泡棉厚度,再次是MCL厚度和泡棉贴附偏移量。最优组合方案在弯折成型和可靠性状态下皆具有最小的金属层应力,其值分别为57 MPa和523 MPa。最优组合方案的弯折成型和可靠性试验达到了100%的产品良品率,满足设计和生产要求。展开更多
基金supported by the National Key R&D Program of China(2018YFB0905400)the National Natural Science Foundation of China(51632001 and 51972131)Chinese Postdoctoral Science Foundation。
文摘Lithium metal has been regarded as the ultimate anode for next-generation rechargeable batteries with high energy density.However,its high reactivity and dendrite growth seriously limit its commercial application,which can be well addressed by realizing uniform Li deposition.Here,we report a facile and scalable one-step vulcanization method to modify commercial Cu foil with lithophilic Cu2S.The in situ formed Cu2S layer can not only promote the homogeneous deposition of Li via its lithophilic nature,but also benefit the formation of a stable solid-electrolyte interphase during initial activation.The Cu2S-modified Cu current collector realizes dendrite-free Li plating/stripping and thus exhibits stable cycling performance with a high Coulombic efficiency,even with a large capacity of 4 mA h cm^-2.A full-cell consisting of a Cu2S/Cu-Li anode and a LiFePO4 cathode exhibits greatly improved cycling stability and enhanced Coulombic efficiency,demonstrating the effectiveness and practicability of the proposed Cu2S/Cu foil in the field of rechargeable Li metal batteries.
基金the financial support from the National Natural Science Foundation of China(Nos.22205191 and 52002346)the Science and Technology Innovation Program of Hunan Province(No.2021RC3109)+1 种基金the Natural Science Foundation of Hunan Province,China(No.2022JJ40446)Guangxi Key Laboratory of Low Carbon Energy Material(No.2020GXKLLCEM01)。
文摘The concentration difference in the near-surface region of lithium metal is the main cause of lithium dendrite growth.Resolving this issue will be key to achieving high-performance lithium metal batteries(LMBs).Herein,we construct a lithium nitrate(LiNO_(3))-implanted electroactiveβphase polyvinylidene fluoride-co-hexafluoropropylene(PVDF-HFP)crystalline polymorph layer(PHL).The electronegatively charged polymer chains attain lithium ions on the surface to form lithium-ion charged channels.These channels act as reservoirs to sustainably release Li ions to recompense the ionic flux of electrolytes,decreasing the growth of lithium dendrites.The stretched molecular channels can also accelerate the transport of Li ions.The combined effects enable a high Coulombic efficiency of 97.0%for 250 cycles in lithium(Li)||copper(Cu)cell and a stable symmetric plating/stripping behavior over 2000 h at 3 mA cm^(-2)with ultrahigh Li utilization of 50%.Furthermore,the full cell coupled with PHL-Cu@Li anode and Li Fe PO_(4) cathode exhibits long-term cycle stability with high-capacity retention of 95.9%after 900 cycles.Impressively,the full cell paired with LiNi_(0.87)Co_(0.1)Mn_(0.03)O_(2)maintains a discharge capacity of 170.0 mAh g^(-1)with a capacity retention of 84.3%after 100 cycles even under harsh condition of ultralow N/P ratio of 0.83.This facile strategy will widen the potential application of LiNO_(3)in ester-based electrolyte for practical high-voltage LMBs.
基金his work is supported by the National Natural Science Foundation of China(Nos.212731&21621091 and 21875195)the National Key Research and Development Program of China(No.2017YFB0102000)the Fundamental Research Funds for the Central Universities(No.20720190040).
文摘The metallic lithium(Li)is considered as the most promising anode material for high-e nergy batteries.Nevertheless,the uncon trollable growth of Li den drite and un stable electrolyte/electrode in terface still hin der the developme nt of Li-based battery.In this work,a no vel strategy has been proposed to stabilize Li anode by in-situ polymerizing polypyrrole(PPy)layer on Ni foam(PPy@Ni foam)as an artificial protective layer.The PPy protective layer can effectively decrease the contact between Li metal and electrolyte during cycling.In addition,the morphology characterization shows that the PPy layer can help the even Li deposition undemeath the layer,leading to a dendrite-free Li anode.As a result,when deposited 2 mAh-cm-2 Li metal,the PPy@Ni foam can keep stable Coulombic efficiency(99%)during nearly 250 cycles,much better than the pure Ni foam(100 cycles).Even in the case of the Li capacity of 10 mAh-cm-2,the stable cycling performance for 60 cycles can still be achieved.Furthermore,when assembled with LiFePO4 material as the cathode for a full cell,the PPy@Ni foam can keep high capacity retention of 85.5%at 500 cycles.In our work,we provide a simple and effective method to enhanee the electrochemical performances of Li metal-based batteries,and reveal a new avenue to design three-dimensional(3D)metallic curre nt collector for protecting the Li metal ano de.
基金supported by the National Key Research and Development Program(2016YFA0202500)National Natural Science Foundation of China(21776019,21808124,51972121)+1 种基金Tip-top Scientific and Technical Innovative Youth Talents of Guangdong Special Support Program(2017TQ04C419)Beijing Natural Science Foundation(L182021)。
文摘Lithium metal batteries are strongly considered as one of the most promising candidates for nextgeneration high-performance battery systems.However,the uncontrollable growth of lithium dendrites and the highly reactive lithium metal result in the severe safety risks and the short lifespan for highenergy-density rechargeable batteries.Here,we demonstrate a hydrophobic and ionically conductive ethylene-vinyl acetate(EVA)copolymer layer can not only endow lithium metal anodes with an air-stable and anti-water surface,but also efficiently suppress the lithium-dendrites growth during the electrochemical cycling process.Therefore,the introduction of the EVA copolymer as a bifunctional protection layer simultaneously improves the anti-water/air performance and electrochemical cycling stability of lithium metal anode.
基金the National Natural Science Foundation of China(Nos.51605276 and51905333)Shanghai Sailing Program(No.19YF1418100)+2 种基金Shanghai Science and Technology Committee Innovation Grant(Nos.17JC1400600 and 17JC1400601)Karamay Science and Technology Major Project(No.2018ZD002B)Aid for Xinjiang Science and Technology Project(No2019E0235)。
文摘Cold metal transfer plus pulse(C+P)arc was applied in the additive manufacturing of 4043 Al alloy parts.Parameters in the manufacturing of the parts were investigated.The properties and microstructure of the parts were also characterized.Experimental results showed that welding at a speed of 8 mm/s and a wire feeding speed of 4.0 m/min was suitable to manufacture thin-walled parts,and the reciprocating scanning method could be adopted to manufacture thick-walled parts.The thin-walled parts of the C+P mode had fewer pores than those of the cold metal transfer(CMT)mode.The thin-and thick-walled parts of the C+P mode showed maximum tensile strengths of 172 and 178 MPa,respectively.Hardness decreased at the interface and in the coarse dendrite and increased in the refined grain area.
基金supported by the National Natural Science Foundation of China (21125419, 50990065, 51010003, 51073058, and 20904011)National Research Project (2009CB623601 and 2009CB930604)
文摘A series of alkali metal salts doped pluronic block copolymer F127 were used as electron injection/transport layers (ETLs) for polymer light-emitting diodes with poly[2-(4-(3′,7′-dimethyloctyloxy)-phenyl)-p-phenylenevinylene] (P-PPV) as the emission layer. It was found that the electron transport capability of F127 can be effectively enhanced by doping with alkali metal salts. By using Li2CO3 (15%) doped F127 as ETL, the resulting device exhibited improved performance with a maximum luminous efficiency (LE) of 13.59 cd/A and a maximum brightness of 5529 cd/m2, while the device with undoped F127 as ETL only showed a maximum LE of 8.78 cd/A and a maximum brightness of 2952 cd/m2. The effects of the doping concentration, cations and anions of the alkali metal salts on the performance of the resulting devices were investigated. It was found that most of the alkali metal salt dopants can dramatically enhance the electron transport capability of F127 ETL and the performance of the resulting devices was greatly improved.
基金financially supported by the National Natural Science Foundation of China(51901249,U1904216)。
文摘Although aqueous zinc ion hybrid capacitors have advantageous integration of batteries and supercapacitors,they still suffer from the inherent problems of dendrite growth and interfacial side reactions on Zn anodes.Herein,a universal fast zinc-ion diffusion layer on a three-dimensional(3 D)mesh structure model is demonstrated to effectively improve Zn plating/stripping reversibility.The fast ion diffusion alloy layer accelerates the Zn^(2+)migration in an orderly manner to homogenize Zn^(2+)flux and overcomes the defects of the commercial mesh substrate,effectively avoiding dendrite growth and side reactions.Consequently,the proof-of-concept silver-zinc alloy modified stainless steel mesh delivers superb reversibility with the high coulombic efficiency over 99.4%at 4 mA cm^(-2)after 1600 cycles and excellent reliability of over 830 h at 1 mA cm^(-2),Its feasibility is also evidenced in commercial zinc ion hybrid capacitors with activated carbon as the cathode.This work enriches the fundamental comprehension of fast zinc-ion diffusion layer combined with a 3 D substrate on the Zn deposition and opens a universal approach to design advanced host for Zn electrodes in zinc ion hybrid capacitors.
基金supported by the National Natural Science Foundation of China(Grant No.52272194)LiaoNing Revitalization Talents Program(Grant No.XLYC2007155).
文摘Potassium metal batteries(PMBs)have become a paramount alternative energy storage technology to lithium-ion batteries,due to their low cost and potential energy density.However,uncontrolled dendrite growth interferes with the stability of the interfacial anode,leading to significant capacity degradation and safety hazards.Herein,a facile reactive prewetting strategy is proposed to discourage dendrite growth by constructing a functional KF/Znrich hybrid interface layer on K metal.The KF/Zn@K anode design functions like an interconnected paddy field,stabilizing the anode interface through the preferential redistribution of Kþflux/electrons,continuous transport paths,and enhanced transport dynamics.As anticipated,symmetrical batteries exhibit an extended cycling lifetime of over 2000 h,with reduced voltage hysteresis at 0.5 mA cm^(-2) and 0.5 mAh cm^(-2).Furthermore,when the KF/Zn@K anode is applied to full batteries coupled with PTCDA,a boosted reversible capacity of 61.6 mAh g1 at 5 C is present over 3000 cycles.This interfacial control creates rational possibilities for constructing highefficiency,stable K metal anodes.
