The separator plays an important part in battery safety and performance.Polyolefin separators are widely used in commercial Lithium-ion batteries(LIBs),owing to their excellent properties,but they suffer from serious ...The separator plays an important part in battery safety and performance.Polyolefin separators are widely used in commercial Lithium-ion batteries(LIBs),owing to their excellent properties,but they suffer from serious thermal shrinkage and poor electrolyte wettability.Thus,a multilayer separator(ASPESA)is developed by coating two thin layers of low-density polyethylene(LDPE)and Al_(2)O_(3)on both sides of a polyethylene membrane using a facile and environmentally friendly casting technique.The ASPESA separator demonstrates a shutdown function at 120℃and shows enhanced thermal stability under 185℃,with a small thermal shrinkage of 1%.Meanwhile,the LDPE and Al_(2)O_(3)layers can improve the electrolyte wettability and electrolyte uptake(407.23%).The multilayer ASPESA separator delivers an excellent cycle performance in LiFePO_(4)||Li cells with a discharge capacity of 144.5 mAh g^(-1)after 900 cycles,with a high-capacity retention of 98.9%(compared to the 5th cycle).Therefore,the multilayer ASPESA separator has great utilization potential as a high-safety separator in LIBs.展开更多
Due to the typical intercalation-deintercalation mechanism,TiO_(2) holds great promise as a sustainable anode for next-generation lithium-ion batteries(LIBs).However,commercial TiO_(2)(C–TiO_(2))is granular and shows...Due to the typical intercalation-deintercalation mechanism,TiO_(2) holds great promise as a sustainable anode for next-generation lithium-ion batteries(LIBs).However,commercial TiO_(2)(C–TiO_(2))is granular and shows slow ionic conductivity,which greatly hinders its development due to sluggish kinetics,leading to low reversible capacity and inferior rate capability.In this study,a two-dimensional layered TiO_(2)(L-TiO_(2))anode is prepared via a one-step calcination process,which can effectively shorten the lithium ions diffusion path and improve its lithium ions conductivity.We elucidated the enhanced electrochemical performance of L-TiO_(2) as an anode in LIBs through pseudocapacitive acceleration of lithium ions intercalation and deintercalation using various characterization techniques,including different scan rate cyclic voltammetry tests,in situ electrochemical impedance spectroscopy,in situ Raman spectroscopy,and in situ X-ray diffraction.In comparison to C–TiO_(2) material,L-TiO_(2) material showcases remarkable electrochemical performance,achieving a capacity of 166 mAh/g after 100 cycles at 0.1 C.Additionally,the lithium-ion diffusion coefficient calculated for the L-TiO_(2) is two orders of magnitude greater,underscoring its potential as a negative electrode material for LIBs.展开更多
通过二维层状Ti_3C_2的原位水热氧化和气相硫化反应,制备了硫掺杂二氧化钛/碳化钛(S-TiO_2/Ti_3C_2)复合材料,并用于电化学储锂。结果表明,二氧化钛纳米颗粒原位生长在碳化钛片层上,且硫成功掺杂到二氧化钛中。这种S-TiO_2/Ti_3C_2复合...通过二维层状Ti_3C_2的原位水热氧化和气相硫化反应,制备了硫掺杂二氧化钛/碳化钛(S-TiO_2/Ti_3C_2)复合材料,并用于电化学储锂。结果表明,二氧化钛纳米颗粒原位生长在碳化钛片层上,且硫成功掺杂到二氧化钛中。这种S-TiO_2/Ti_3C_2复合结构作为锂离子电池的负极材料,表现出较好的电化学性能。在0.2 A/g的电流密度下循环100圈后,放电比容量稳定在288 m A·h/g,远高于纯Ti_3C_2和TiO_2/Ti_3C_2电极的放电比容量。S-TiO_2/Ti_3C_2复合材料表现出的较高比容量和良好的循环性能,主要归因于复合材料的特殊纳米结构优势:二氧化钛原位生长在碳化钛上,使复合材料具有稳定良好的接触界面,能够促进电子的快速转移,同时可以有效避免循环过程中两种组分的分离;硫在二氧化钛中的掺杂可以提高二氧化钛的导电性,并引入缺陷,提高反应活性。此研究工作为二维材料的原位转化及复合提供了新的思路和研究方法。展开更多
为了实现硅纳米颗粒与一维碳纳米纤维的高效复合,提高硅材料作为锂离子电池负极的电化学性能,通过同轴静电纺丝法构造了硅碳复合结构(Si/C-C)的一维纳米纤维作为锂离子电池的负极材料.通过SEM、TEM、XRD和电化学性能测试对其结构、形貌...为了实现硅纳米颗粒与一维碳纳米纤维的高效复合,提高硅材料作为锂离子电池负极的电化学性能,通过同轴静电纺丝法构造了硅碳复合结构(Si/C-C)的一维纳米纤维作为锂离子电池的负极材料.通过SEM、TEM、XRD和电化学性能测试对其结构、形貌、成分和电化学性能等进行分析.结果表明:Si/C-C纳米复合纤维的平均直径为500~700 nm,硅含量为22%~33%;在100 m A/g的电流密度下,经100圈循环后其可逆容量维持在1 000 m Ah/g,表现出较佳的循环稳定性和较高的可逆比容量.研究表明,一维复合纳米纤维电化学性能的提升主要归因于硅碳复合结构中一维纳米纤维为硅提供了保护层,一方面有效抑制了硅的体积膨胀,另一方面提升了硅的电子导电性并有效缩短了离子迁移路径.展开更多
Lithium-ion batteries with high-energy density are extensively commercialized in long-range electric vehicles. However, they are poor in thermal stability and pose fire or explosion, which has attracted the global att...Lithium-ion batteries with high-energy density are extensively commercialized in long-range electric vehicles. However, they are poor in thermal stability and pose fire or explosion, which has attracted the global attention. This study describes a new route to mitigate the battery thermal runaway(TR) hazard by poison agents. First, the self-destructive cell is built using the embedded poison layer. Then, the poisoning mechanism and paths are experimentally investigated at the material, electrode, and cell levels. Finally, the proposed route is verified by TR tests. The results show the TR hazard can be significantly reduced in the self-destructive cell based on a new reaction sequence regulation. Specifically, the maximum temperature of the self-destructive cell is more than 300℃ lower than that of the normal cell during TR. The drop in maximum temperature can reduce total heat release and the probability of TR propagation in the battery system, significantly improving battery safety.展开更多
Aiming to improve the battery performance of lithium-ion batteries(LIBs),modification of the cathodes and anodes of LIBs using laser beams to prepare through-holes,non-through-holes or ditches arranged in grid and lin...Aiming to improve the battery performance of lithium-ion batteries(LIBs),modification of the cathodes and anodes of LIBs using laser beams to prepare through-holes,non-through-holes or ditches arranged in grid and line patterns has been proposed by many researchers and engineers.In this study,a laser processing system attached to rollers,which realizes this modification without large changes in the present mass-production system,was developed.The laser system apparatus comprises roll-to-roll equipment and laser equipment.The roll-to-roll equipment mainly consists of a hollow cylinder with openings on its circumferential surface.Cathode and anode electrodes for LIBs are wound around the cylinder in the longitudinal direction of the electrodes.A pulsed beam reflected from the central axis of the cylinder can continuously open a large number of through-holes in the thin electrodes.Through-holes were formed at a rate of 100000 holes per second on lithium iron phosphate cathodes and graphite anodes with this system.The through-holed cathodes and anodes prepared with this system exhibited higher C-rate performance than nontreated cathodes and anodes.展开更多
采用水热法,以锡酸钠为原料,醋酸锌为锌料,制备出锌掺杂量不同的SnO_2纳米负极材料。电压在0.01~3.0 V,电流密度为100 m A/g的条件下进行电化学测试,结果表明锌掺杂量10%的SnO_2材料首次放电容量可达1895.3 m Ah/g,50次循环后放容量保持...采用水热法,以锡酸钠为原料,醋酸锌为锌料,制备出锌掺杂量不同的SnO_2纳米负极材料。电压在0.01~3.0 V,电流密度为100 m A/g的条件下进行电化学测试,结果表明锌掺杂量10%的SnO_2材料首次放电容量可达1895.3 m Ah/g,50次循环后放容量保持206.1 m Ah/g。因此,锌掺杂量10%的SnO_2材料有较好的电化学性能。展开更多
Current research on vanadium oxides in lithium ion batteries （LIBs） considers them as cathode materials, whereas they are rarely studied for use as anodes in LIBs because of their low electrical conductivity and rap...Current research on vanadium oxides in lithium ion batteries （LIBs） considers them as cathode materials, whereas they are rarely studied for use as anodes in LIBs because of their low electrical conductivity and rapid capacity fading. In this work, hydrogenated vanadium oxide nanoneedles were prepared and incorporated into freeze-dried graphene foam. The hydrogenated vanadium oxides show greatly improved charge-transfer kinetics, which lead to excellent electrochemical properties. When tested as anode materials （0.005-3.0 V vs. Li/Li＋） in LIBs, the sample activated at 600℃ exhibits high specific capacity （-941 mA-h-g-1 at 100 mA.g-1） and high-rate capability （-504 mA·h·g-1 at 5 A·g-1）, as well as excellent cycling performance （-285 mA.h.g-1 in the 1,000th cycle at 5A-g-1）. These results demonstrate the promising application of vanadium oxides as anodes in LIBs.展开更多
锂离子电池硅负极材料具有很高的理论比容量(4200 m Ah/g),但其在充放电过程中巨大的体积变化导致循环性能很差,同时较低的电导率也限制了硅在锂离子电池中的应用前景。将硅与其它材料进行复合是改善硅基负极材料循环稳定性、提高其倍...锂离子电池硅负极材料具有很高的理论比容量(4200 m Ah/g),但其在充放电过程中巨大的体积变化导致循环性能很差,同时较低的电导率也限制了硅在锂离子电池中的应用前景。将硅与其它材料进行复合是改善硅基负极材料循环稳定性、提高其倍率性能的主要途径。文章综述了近年来硅基复合材料的研究进展,以期为硅基复合材料的研究提供参考。展开更多
基金Foundation item：The project supposed by National Natural Science Foundation of China（20376086）Postdoctoral Science Foundation of China（2005037700）Postdoctoral science Foundation of Central South University,China（2004107）
基金supported by Jilin Province Science and Technology Department major science and technology project(grant numbers 20220301004GX,20220301005GX)Key Subject Construction of Physical Chemistry of Northeast Normal University,the Education Department of Jilin Province science and technology project of“13th Five-Year”(grant number JJKH20200764KJ)the Fundamental Research Funds for the Central Universities(grant number 135113014).
文摘The separator plays an important part in battery safety and performance.Polyolefin separators are widely used in commercial Lithium-ion batteries(LIBs),owing to their excellent properties,but they suffer from serious thermal shrinkage and poor electrolyte wettability.Thus,a multilayer separator(ASPESA)is developed by coating two thin layers of low-density polyethylene(LDPE)and Al_(2)O_(3)on both sides of a polyethylene membrane using a facile and environmentally friendly casting technique.The ASPESA separator demonstrates a shutdown function at 120℃and shows enhanced thermal stability under 185℃,with a small thermal shrinkage of 1%.Meanwhile,the LDPE and Al_(2)O_(3)layers can improve the electrolyte wettability and electrolyte uptake(407.23%).The multilayer ASPESA separator delivers an excellent cycle performance in LiFePO_(4)||Li cells with a discharge capacity of 144.5 mAh g^(-1)after 900 cycles,with a high-capacity retention of 98.9%(compared to the 5th cycle).Therefore,the multilayer ASPESA separator has great utilization potential as a high-safety separator in LIBs.
基金supported by National Natural Science Foundation of China(grant No.202101AW070006)Yunnan Major Scientific and Technological Projects(grant No.202202AG050003)+1 种基金the Basic Research Plan(Key Project)of Yunnan Province(grant Nos.202101BE070001-018,202201AT070070)the National Youth Talent Support Program of Yunnan Province,China(grant No.YNQR-QNRC-2020-011).
文摘Due to the typical intercalation-deintercalation mechanism,TiO_(2) holds great promise as a sustainable anode for next-generation lithium-ion batteries(LIBs).However,commercial TiO_(2)(C–TiO_(2))is granular and shows slow ionic conductivity,which greatly hinders its development due to sluggish kinetics,leading to low reversible capacity and inferior rate capability.In this study,a two-dimensional layered TiO_(2)(L-TiO_(2))anode is prepared via a one-step calcination process,which can effectively shorten the lithium ions diffusion path and improve its lithium ions conductivity.We elucidated the enhanced electrochemical performance of L-TiO_(2) as an anode in LIBs through pseudocapacitive acceleration of lithium ions intercalation and deintercalation using various characterization techniques,including different scan rate cyclic voltammetry tests,in situ electrochemical impedance spectroscopy,in situ Raman spectroscopy,and in situ X-ray diffraction.In comparison to C–TiO_(2) material,L-TiO_(2) material showcases remarkable electrochemical performance,achieving a capacity of 166 mAh/g after 100 cycles at 0.1 C.Additionally,the lithium-ion diffusion coefficient calculated for the L-TiO_(2) is two orders of magnitude greater,underscoring its potential as a negative electrode material for LIBs.
文摘通过二维层状Ti_3C_2的原位水热氧化和气相硫化反应,制备了硫掺杂二氧化钛/碳化钛(S-TiO_2/Ti_3C_2)复合材料,并用于电化学储锂。结果表明,二氧化钛纳米颗粒原位生长在碳化钛片层上,且硫成功掺杂到二氧化钛中。这种S-TiO_2/Ti_3C_2复合结构作为锂离子电池的负极材料,表现出较好的电化学性能。在0.2 A/g的电流密度下循环100圈后,放电比容量稳定在288 m A·h/g,远高于纯Ti_3C_2和TiO_2/Ti_3C_2电极的放电比容量。S-TiO_2/Ti_3C_2复合材料表现出的较高比容量和良好的循环性能,主要归因于复合材料的特殊纳米结构优势:二氧化钛原位生长在碳化钛上,使复合材料具有稳定良好的接触界面,能够促进电子的快速转移,同时可以有效避免循环过程中两种组分的分离;硫在二氧化钛中的掺杂可以提高二氧化钛的导电性,并引入缺陷,提高反应活性。此研究工作为二维材料的原位转化及复合提供了新的思路和研究方法。
文摘为了实现硅纳米颗粒与一维碳纳米纤维的高效复合,提高硅材料作为锂离子电池负极的电化学性能,通过同轴静电纺丝法构造了硅碳复合结构(Si/C-C)的一维纳米纤维作为锂离子电池的负极材料.通过SEM、TEM、XRD和电化学性能测试对其结构、形貌、成分和电化学性能等进行分析.结果表明:Si/C-C纳米复合纤维的平均直径为500~700 nm,硅含量为22%~33%;在100 m A/g的电流密度下,经100圈循环后其可逆容量维持在1 000 m Ah/g,表现出较佳的循环稳定性和较高的可逆比容量.研究表明,一维复合纳米纤维电化学性能的提升主要归因于硅碳复合结构中一维纳米纤维为硅提供了保护层,一方面有效抑制了硅的体积膨胀,另一方面提升了硅的电子导电性并有效缩短了离子迁移路径.
基金supported by the National Natural Science Foundation of China (52076121, 51977131, and 51877138)the Natural Science Foundation of Shanghai (19ZR1435800)+1 种基金the State Key Lab-oratory of Automotive Safety and Energy under Project No. KF2020the Shanghai Science and Technology Development Fund(19QA1406200)。
文摘Lithium-ion batteries with high-energy density are extensively commercialized in long-range electric vehicles. However, they are poor in thermal stability and pose fire or explosion, which has attracted the global attention. This study describes a new route to mitigate the battery thermal runaway(TR) hazard by poison agents. First, the self-destructive cell is built using the embedded poison layer. Then, the poisoning mechanism and paths are experimentally investigated at the material, electrode, and cell levels. Finally, the proposed route is verified by TR tests. The results show the TR hazard can be significantly reduced in the self-destructive cell based on a new reaction sequence regulation. Specifically, the maximum temperature of the self-destructive cell is more than 300℃ lower than that of the normal cell during TR. The drop in maximum temperature can reduce total heat release and the probability of TR propagation in the battery system, significantly improving battery safety.
基金supported by‘Advanced Research Infrastructure for Materials and Nanotechnology in Japan(ARIM)’of the Ministry of Education,Culture,Sports,Science and Technology(MEXT).Proposal Number 22KU0036。
文摘Aiming to improve the battery performance of lithium-ion batteries(LIBs),modification of the cathodes and anodes of LIBs using laser beams to prepare through-holes,non-through-holes or ditches arranged in grid and line patterns has been proposed by many researchers and engineers.In this study,a laser processing system attached to rollers,which realizes this modification without large changes in the present mass-production system,was developed.The laser system apparatus comprises roll-to-roll equipment and laser equipment.The roll-to-roll equipment mainly consists of a hollow cylinder with openings on its circumferential surface.Cathode and anode electrodes for LIBs are wound around the cylinder in the longitudinal direction of the electrodes.A pulsed beam reflected from the central axis of the cylinder can continuously open a large number of through-holes in the thin electrodes.Through-holes were formed at a rate of 100000 holes per second on lithium iron phosphate cathodes and graphite anodes with this system.The through-holed cathodes and anodes prepared with this system exhibited higher C-rate performance than nontreated cathodes and anodes.
文摘采用水热法,以锡酸钠为原料,醋酸锌为锌料,制备出锌掺杂量不同的SnO_2纳米负极材料。电压在0.01~3.0 V,电流密度为100 m A/g的条件下进行电化学测试,结果表明锌掺杂量10%的SnO_2材料首次放电容量可达1895.3 m Ah/g,50次循环后放容量保持206.1 m Ah/g。因此,锌掺杂量10%的SnO_2材料有较好的电化学性能。
文摘Current research on vanadium oxides in lithium ion batteries （LIBs） considers them as cathode materials, whereas they are rarely studied for use as anodes in LIBs because of their low electrical conductivity and rapid capacity fading. In this work, hydrogenated vanadium oxide nanoneedles were prepared and incorporated into freeze-dried graphene foam. The hydrogenated vanadium oxides show greatly improved charge-transfer kinetics, which lead to excellent electrochemical properties. When tested as anode materials （0.005-3.0 V vs. Li/Li＋） in LIBs, the sample activated at 600℃ exhibits high specific capacity （-941 mA-h-g-1 at 100 mA.g-1） and high-rate capability （-504 mA·h·g-1 at 5 A·g-1）, as well as excellent cycling performance （-285 mA.h.g-1 in the 1,000th cycle at 5A-g-1）. These results demonstrate the promising application of vanadium oxides as anodes in LIBs.
文摘锂离子电池硅负极材料具有很高的理论比容量(4200 m Ah/g),但其在充放电过程中巨大的体积变化导致循环性能很差,同时较低的电导率也限制了硅在锂离子电池中的应用前景。将硅与其它材料进行复合是改善硅基负极材料循环稳定性、提高其倍率性能的主要途径。文章综述了近年来硅基复合材料的研究进展,以期为硅基复合材料的研究提供参考。
