Li3N is an excellent zero-residue positive electrode pre-lithiation additive to offset the initial lithium loss in lithium-ion capacitors. However, Li3N has an intrinsic problem of poor compatibility with commonly use...Li3N is an excellent zero-residue positive electrode pre-lithiation additive to offset the initial lithium loss in lithium-ion capacitors. However, Li3N has an intrinsic problem of poor compatibility with commonly used aprotic polar solvents in electrode manufacture procedure due to its high reactivity with commonly used solvents like N-methy-2-pyrrolidone(NMP) and etc. It is the Valley of Death between research and large-scale commercialization of Li-ion capacitors using Li3N as prelithiation agent. In this work, Li3N containing electrode is prepared by a commercially adoptable route for the first time, using N,Ndimethylformamide(DMF) to homogenate the electrode slurry. The DMF molecular stabilizing mechanism is confirmed via experiment analysis and DFT simulation, indicating that the dehydrogenation energy for DMF is obviously larger than other commonly used solvents such as NMP and etc. The soft package lithium-ion capacitors(LIC250) with only 12 wt% Li3N addition in AC positive electrode exhibits excellent rate capability, cyclic stability and ultrahigh specific energy. Its specific energy is 2.3 times higher than the Li3N-free devices, with energy retention as high as 90% after 10,000 cycles.展开更多
The severe lithium(Li)dendrite growth leads to poor cycling stability and serious safety hazards of Li metal batteries,which completely impedes their practical applications.Herein,a novel Li nucleation-diffusion-growt...The severe lithium(Li)dendrite growth leads to poor cycling stability and serious safety hazards of Li metal batteries,which completely impedes their practical applications.Herein,a novel Li nucleation-diffusion-growth mechanism based on Li-Sn alloy/Li_(3) N electrolyte(LS/LN)composite interface layer is proposed,which synergistically guides the horizontal deposition of Li to suppress the vertical growth of Li dendrite and side reactions with the electrolyte.The lithiophilic Li-Sn alloy captures Li ions to nucleate preferentially on the alloy sites,and simultaneously the Li_(3) N with low diffusion energy barrier and high Li-ion conductivity efficiently transports Li ions to nucleation sites during Li plating,consequently promoting the Li horizontal deposition.As a result,the LS/LN-Li symmetric cells can stably cycle 1600 h even at a high current density of 5 mA cm^(-2) and deposition capacity of 5 mA h cm^(-2).The LiFePO_(4)|LS/LN-Li cells with a high loading of 8.2 mg cm^(-2) present a high capacity retention of 93.4%after 1000 cycles,much higher than that using bare Li(64.8%).Furthermore,the LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)|LS/LN-Li cells present more excellent cycling stability than the cells using bare Li.The Li nucleation-diffusion-growth mechanism opens a promising route to solve the challenge of the vertical growth of Li dendrite and achieve highly stable Li metal batteries.展开更多
Nitriles were unexpectedly trimerized into s-triazines or amino-pyrimidines in high yields in the presence of catalytic amount of Li3N, resulting in a simple, solvent-free and easy-to-scale-up one-pot way to synthesiz...Nitriles were unexpectedly trimerized into s-triazines or amino-pyrimidines in high yields in the presence of catalytic amount of Li3N, resulting in a simple, solvent-free and easy-to-scale-up one-pot way to synthesize s-triazines and 4-amino-pyrimidines with high yield.展开更多
基金the National Natural Science Foundation of China(51673199 and 51677176)Youth Inn ovation Promotion Association of Chinese Academy of Sciences(2015148)+4 种基金Dalian National Laboratory for Clean Energy(DNL180307)Innovation Foundation of Dalian Institute of Chemical PhysicsChinese Academy of Sciences(ZZBS201615 and ZZBS201708)Dalian Science and Technology Star Program(2016RQ026)The authors also thank Lei Shi for the helpful discussion on Li3N related reaction.
文摘Li3N is an excellent zero-residue positive electrode pre-lithiation additive to offset the initial lithium loss in lithium-ion capacitors. However, Li3N has an intrinsic problem of poor compatibility with commonly used aprotic polar solvents in electrode manufacture procedure due to its high reactivity with commonly used solvents like N-methy-2-pyrrolidone(NMP) and etc. It is the Valley of Death between research and large-scale commercialization of Li-ion capacitors using Li3N as prelithiation agent. In this work, Li3N containing electrode is prepared by a commercially adoptable route for the first time, using N,Ndimethylformamide(DMF) to homogenate the electrode slurry. The DMF molecular stabilizing mechanism is confirmed via experiment analysis and DFT simulation, indicating that the dehydrogenation energy for DMF is obviously larger than other commonly used solvents such as NMP and etc. The soft package lithium-ion capacitors(LIC250) with only 12 wt% Li3N addition in AC positive electrode exhibits excellent rate capability, cyclic stability and ultrahigh specific energy. Its specific energy is 2.3 times higher than the Li3N-free devices, with energy retention as high as 90% after 10,000 cycles.
基金supported by the Key-Area Research and Development Program of Guangdong Province (2020B090919001)the National Natural Science Foundation of China (U2001220)+3 种基金Local Innovative Research Teams Project of Guangdong Pearl River Talents Program (2017BT01N111)Shenzhen Technical Plan Project (JCYJ20180508152210821, JCYJ20170817161221958, and JCYJ20180508152135822)the All-Solid-State Lithium Battery Electrolyte Engineering Research Center (XMHT202002030)Shenzhen Graphene Manufacturing Innovation Center (201901161513)
文摘The severe lithium(Li)dendrite growth leads to poor cycling stability and serious safety hazards of Li metal batteries,which completely impedes their practical applications.Herein,a novel Li nucleation-diffusion-growth mechanism based on Li-Sn alloy/Li_(3) N electrolyte(LS/LN)composite interface layer is proposed,which synergistically guides the horizontal deposition of Li to suppress the vertical growth of Li dendrite and side reactions with the electrolyte.The lithiophilic Li-Sn alloy captures Li ions to nucleate preferentially on the alloy sites,and simultaneously the Li_(3) N with low diffusion energy barrier and high Li-ion conductivity efficiently transports Li ions to nucleation sites during Li plating,consequently promoting the Li horizontal deposition.As a result,the LS/LN-Li symmetric cells can stably cycle 1600 h even at a high current density of 5 mA cm^(-2) and deposition capacity of 5 mA h cm^(-2).The LiFePO_(4)|LS/LN-Li cells with a high loading of 8.2 mg cm^(-2) present a high capacity retention of 93.4%after 1000 cycles,much higher than that using bare Li(64.8%).Furthermore,the LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)|LS/LN-Li cells present more excellent cycling stability than the cells using bare Li.The Li nucleation-diffusion-growth mechanism opens a promising route to solve the challenge of the vertical growth of Li dendrite and achieve highly stable Li metal batteries.
文摘Nitriles were unexpectedly trimerized into s-triazines or amino-pyrimidines in high yields in the presence of catalytic amount of Li3N, resulting in a simple, solvent-free and easy-to-scale-up one-pot way to synthesize s-triazines and 4-amino-pyrimidines with high yield.
