The increasing demand for short charging time on electric vehicles has motivated realization of fast chargeable lithium-ion batteries(LIBs).However,shortening the charging time of LIBs is limited by Li^(+)intercalatio...The increasing demand for short charging time on electric vehicles has motivated realization of fast chargeable lithium-ion batteries(LIBs).However,shortening the charging time of LIBs is limited by Li^(+)intercalation process consisting of liquid-phase diffusion,de-solvation,SEI crossing,and solid-phase diffusion.Herein,we propose a new strategy to accelerate the de-solvation step through a control of interaction between polymeric binder and solvent-Li^(+)complexes.For this purpose,three alkali metal ions(Li^(+),Na^(+),and K^(+))substituted carboxymethyl cellulose(Li-,Na-,and K-CMC)are prepared to examine the effects of metal ions on their performances.The lowest activation energy of de-solvation and the highest chemical diffusion coefficient were observed for Li-CMC.Specifically,Li-CMC cell with a capacity of 3 mAh cm^(-2)could be charged to>95%in 10 min,while a value above>85%was observed after 150 cycles.Thus,the presented approach holds great promise for the realization of fast charging.展开更多
A series of anodic aluminum oxide(AAO) was grown on the commercially pure 1050 aluminum sheet by controlling electrolyte temperature(2-15 ℃) and anodizing time(0.5-6 h),using a fixed applied current density of 3 A/dm...A series of anodic aluminum oxide(AAO) was grown on the commercially pure 1050 aluminum sheet by controlling electrolyte temperature(2-15 ℃) and anodizing time(0.5-6 h),using a fixed applied current density of 3 A/dm2 in diluted sulfuric acid electrolyte.A crack-free thick AAO with the thickness of 105-120 μm and containing unidirectional nano sized pores(average pore diameter of 5-7 nm) is successfully achieved in the specimens anodized for 2 h,irrespective of electrolyte temperature.When anodizing time reaches 6 h,very thick AAO with the thickness of 230-284 μm is grown,and average diameter of unidirectional pores is in the range of 6-24 nm.The higher values in both the AAO thickness and pore diameter are attained for the specimens anodized at higher temperatures of 10-15 ℃.A crack is observed to exist in the AAO after anodizing up to 4 h and more.A higher fraction(more than 9%) of the crack is shown in the specimens anodized at higher temperatures of 10-15 ℃ for 6 h and a considerable amount of giant cracks are contained.展开更多
基金supported by Electronics and Telecommunications Research Institute(ETRI)grant funded by the Korea government(20ZB1200,Development of ICT Materials,Components and Equipment Technologies)the National Research Foundation of Korea(NRF)grant funded by the Korea government(No.2020R1A4A4079810)funding from the National Research Foundation(NRF)funded by the Ministry of Science and ICT,Rep.of Korea(Project No.2021R1C1C1008776)
文摘The increasing demand for short charging time on electric vehicles has motivated realization of fast chargeable lithium-ion batteries(LIBs).However,shortening the charging time of LIBs is limited by Li^(+)intercalation process consisting of liquid-phase diffusion,de-solvation,SEI crossing,and solid-phase diffusion.Herein,we propose a new strategy to accelerate the de-solvation step through a control of interaction between polymeric binder and solvent-Li^(+)complexes.For this purpose,three alkali metal ions(Li^(+),Na^(+),and K^(+))substituted carboxymethyl cellulose(Li-,Na-,and K-CMC)are prepared to examine the effects of metal ions on their performances.The lowest activation energy of de-solvation and the highest chemical diffusion coefficient were observed for Li-CMC.Specifically,Li-CMC cell with a capacity of 3 mAh cm^(-2)could be charged to>95%in 10 min,while a value above>85%was observed after 150 cycles.Thus,the presented approach holds great promise for the realization of fast charging.
文摘A series of anodic aluminum oxide(AAO) was grown on the commercially pure 1050 aluminum sheet by controlling electrolyte temperature(2-15 ℃) and anodizing time(0.5-6 h),using a fixed applied current density of 3 A/dm2 in diluted sulfuric acid electrolyte.A crack-free thick AAO with the thickness of 105-120 μm and containing unidirectional nano sized pores(average pore diameter of 5-7 nm) is successfully achieved in the specimens anodized for 2 h,irrespective of electrolyte temperature.When anodizing time reaches 6 h,very thick AAO with the thickness of 230-284 μm is grown,and average diameter of unidirectional pores is in the range of 6-24 nm.The higher values in both the AAO thickness and pore diameter are attained for the specimens anodized at higher temperatures of 10-15 ℃.A crack is observed to exist in the AAO after anodizing up to 4 h and more.A higher fraction(more than 9%) of the crack is shown in the specimens anodized at higher temperatures of 10-15 ℃ for 6 h and a considerable amount of giant cracks are contained.