GHz burst-mode femtosecond(fs)laser,which emits a series of pulse trains with extremely short intervals of several hundred picoseconds,provides distinct characteristics in materials processing as compared with the con...GHz burst-mode femtosecond(fs)laser,which emits a series of pulse trains with extremely short intervals of several hundred picoseconds,provides distinct characteristics in materials processing as compared with the conventional irradiation scheme of fs laser(single-pulse mode).In this paper,we take advantage of the moderate pulse interval of 205 ps(4.88 GHz)in the burst pulse for high-quality and high-efficiency micromachining of single crystalline sapphire by laser induced plasma assisted ablation(LIPAA).Specifically,the preceding pulses in the burst generate plasma by ablation of copper placed behind the sapphire substrate,which interacts with the subsequent pulses to induce ablation at the rear surface of sapphire substrates.As a result,not only the ablation quality but also the ablation efficiency and the fabrication resolution are greatly improved compared to the other schemes including single-pulse mode fs laser direct ablation,single-pulse mode fs-LIPAA,and nanosecond-LIPAA.展开更多
Among the alternatives to lithium-ion batteries,lithium-sulfur(Li-S)batteries are considered as an attractive option because of their high theoretical energy density of 2570 Wh kg^(−1).However,the application of the L...Among the alternatives to lithium-ion batteries,lithium-sulfur(Li-S)batteries are considered as an attractive option because of their high theoretical energy density of 2570 Wh kg^(−1).However,the application of the Li-S battery has been plagued by the rapid failure of the Li anode due to the Li dendrite growth and severe parasitic reactions between Li and lithium polysulfides.The physicochemical properties of the solid-electrolyte interphase have a profound impact on the performance of the Li anode.Herein,a lithium polyacrylic acid/lithium nitrate(LPL)-protective layer is developed to inhibit the dendrite Li growth and parasitic reactions by tailoring the spatial distribution and content of LiN_(x)O_(y) and Li_(3)N at the SEI.The modified SEI is thoroughly investigated for compositions,ion transport properties,and Li plating/stripping kinetics.Consequently,the Li-S cell with a high S loading cathode(5.0 mg cm^(−2)),LPL layer-protected thin Li anode(50μm),and 40μL electrolyte shows a long life span of 120 cycles.This work evokes the avenue for regulating the spatial distribution of inorganic nitride at the SEI to suppress the formation of Li dendrites and parasitic reactions in Li-S batteries and perhaps guiding the design of analogous battery systems.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
The Li-and Mn-rich layered oxides(R-LNCM)are considered as promising cathode materials for high-energy density lithium-ion batteries(LIBs).However,the interface side reaction aggravates the voltage and capacity fading...The Li-and Mn-rich layered oxides(R-LNCM)are considered as promising cathode materials for high-energy density lithium-ion batteries(LIBs).However,the interface side reaction aggravates the voltage and capacity fading between cathode material and electrolyte at high voltage,which severely hinders the practical application of LIB s.Herein,lithium polyacrylate(LiPAA)as the binder and coating agent is applied to suppress the voltage and capacity fading of R-LNCM electrode.The flexible LiPAA layers with high elasticity are capable of impeding cathode cracks on the particle surface via mechanical stress relief.Thus,superior voltage and capacity fading suppression on R-LNCM electrode is finally achieved.As a result,LiPAA-R-LNCM cathode exhibits a remarkable specific capacity of 186 mA·h·g^(-1)with~73%retention at 1℃after 200cycles.Further,the corresponding average discharge potential is maintained to~3.1 V with only~0.4 V falling.展开更多
基金supported by MEXT Quantum Leap Flagship Program(MEXT Q-LEAP)Grant Number JPMXS0118067246.
文摘GHz burst-mode femtosecond(fs)laser,which emits a series of pulse trains with extremely short intervals of several hundred picoseconds,provides distinct characteristics in materials processing as compared with the conventional irradiation scheme of fs laser(single-pulse mode).In this paper,we take advantage of the moderate pulse interval of 205 ps(4.88 GHz)in the burst pulse for high-quality and high-efficiency micromachining of single crystalline sapphire by laser induced plasma assisted ablation(LIPAA).Specifically,the preceding pulses in the burst generate plasma by ablation of copper placed behind the sapphire substrate,which interacts with the subsequent pulses to induce ablation at the rear surface of sapphire substrates.As a result,not only the ablation quality but also the ablation efficiency and the fabrication resolution are greatly improved compared to the other schemes including single-pulse mode fs laser direct ablation,single-pulse mode fs-LIPAA,and nanosecond-LIPAA.
基金partially supported by grants from the National Natural Science Foundation of China(51772069 and 52072099).
文摘Among the alternatives to lithium-ion batteries,lithium-sulfur(Li-S)batteries are considered as an attractive option because of their high theoretical energy density of 2570 Wh kg^(−1).However,the application of the Li-S battery has been plagued by the rapid failure of the Li anode due to the Li dendrite growth and severe parasitic reactions between Li and lithium polysulfides.The physicochemical properties of the solid-electrolyte interphase have a profound impact on the performance of the Li anode.Herein,a lithium polyacrylic acid/lithium nitrate(LPL)-protective layer is developed to inhibit the dendrite Li growth and parasitic reactions by tailoring the spatial distribution and content of LiN_(x)O_(y) and Li_(3)N at the SEI.The modified SEI is thoroughly investigated for compositions,ion transport properties,and Li plating/stripping kinetics.Consequently,the Li-S cell with a high S loading cathode(5.0 mg cm^(−2)),LPL layer-protected thin Li anode(50μm),and 40μL electrolyte shows a long life span of 120 cycles.This work evokes the avenue for regulating the spatial distribution of inorganic nitride at the SEI to suppress the formation of Li dendrites and parasitic reactions in Li-S batteries and perhaps guiding the design of analogous battery systems.
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financial support from the National Key Research and Development Program of China (Grant No.2021YFB2400401)Project of Development Fund of Key Laboratory of Green Plateau and Ecological Community of Qinghai Province (Grant No.SL-2020-019)。
文摘The Li-and Mn-rich layered oxides(R-LNCM)are considered as promising cathode materials for high-energy density lithium-ion batteries(LIBs).However,the interface side reaction aggravates the voltage and capacity fading between cathode material and electrolyte at high voltage,which severely hinders the practical application of LIB s.Herein,lithium polyacrylate(LiPAA)as the binder and coating agent is applied to suppress the voltage and capacity fading of R-LNCM electrode.The flexible LiPAA layers with high elasticity are capable of impeding cathode cracks on the particle surface via mechanical stress relief.Thus,superior voltage and capacity fading suppression on R-LNCM electrode is finally achieved.As a result,LiPAA-R-LNCM cathode exhibits a remarkable specific capacity of 186 mA·h·g^(-1)with~73%retention at 1℃after 200cycles.Further,the corresponding average discharge potential is maintained to~3.1 V with only~0.4 V falling.
