The rate and cycling performances of the electrode materials are affected by many factors in a practical complicated electrode process.Learning about the limiting step in a practical electrochemical reaction is very i...The rate and cycling performances of the electrode materials are affected by many factors in a practical complicated electrode process.Learning about the limiting step in a practical electrochemical reaction is very important to effectively improve the electrochemical performances of the electrode materials.Li4Ti5O12,as a zero-strain material,has been considered as a promising anode material for long life Li-ion batteries.In this study,our results show that the Li4Ti5O12 pasted on Cu or graphite felt current collector exhibits unexpectedly higher rate performance than on Al current collector. For Li4Ti5O12,the electron transfer between current collector and active material is the critical factor that affects its rate and cycling performances.展开更多
This is the first time that a novel anode material,spinel (Li_4Ti_5O_(12)) which is well known as a "zero-strain" anode material for lithium storage,has been introduced for sodium-ion battery.The (Li_4Ti_5O_...This is the first time that a novel anode material,spinel (Li_4Ti_5O_(12)) which is well known as a "zero-strain" anode material for lithium storage,has been introduced for sodium-ion battery.The (Li_4Ti_5O_(12)) shows an average Na storage voltage of about 1.0 V and a reversible capacity of about 145 mAh/g,thereby making it a promising anode for sodiumion battery.Ex-situ X-ray diffraction (XRD) is used to investigate the structure change in the Na insertion/deinsertion process.Based on this,a possible Na storage mechanism is proposed.展开更多
水系锌离子电池具有低成本、高安全的特点,有望应用于大规模储能.然而,锌负极的循环稳定性仍不理想,且水系电池缺少合适的亲水隔膜,这限制了水系锌离子电池的实际应用.在本文中,我们报道了一种可用于水系电池的分级多孔的聚偏二氟乙烯-...水系锌离子电池具有低成本、高安全的特点,有望应用于大规模储能.然而,锌负极的循环稳定性仍不理想,且水系电池缺少合适的亲水隔膜,这限制了水系锌离子电池的实际应用.在本文中,我们报道了一种可用于水系电池的分级多孔的聚偏二氟乙烯-双三氟甲磺酰亚胺锂(PVDF-LiTFSI)(PVDF-Li)隔膜.均匀混合的LiTFSI盐降低了PVDF的结晶性,使隔膜具有优异的机械强度,并形成分级的孔隙结构.这种LiTFSI诱导的分级多孔结构有助于实现Zn2+的快速传输和锌的均匀沉积,同时保证隔膜在水系电解液中具有优异的润湿性.这种先进的PVDF-Li隔膜能显著抑制锌枝晶的生长,提高水系锌离子电池的循环寿命.因此,使用PVDF-Li隔膜的Zn||V2O5电池的初始容量达324 mA h g-1,比传统玻璃纤维隔膜高27%,且容量保持率也得到大幅提升.该研究设计了一种功能隔膜来调控正负极反应的均匀性,这为高性能水系电池的开发提供了新的思路.展开更多
基金supported by the "Hundred Talent Project" of the Chinese Academy of Sciencesthe National High Technology Research and Development Program of China(Grant No.2009AA033101)+3 种基金the National Basic Research Program of China(Grant Nos.2007CB936500 and 2010CB833102)the National Natural Science Foundation of China(Grant No.50972164)the Science and Technology Planning Project of Guangdong Province,China(Grant No.2010A090602001)the Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No.KJCX2-YW-W26)
文摘The rate and cycling performances of the electrode materials are affected by many factors in a practical complicated electrode process.Learning about the limiting step in a practical electrochemical reaction is very important to effectively improve the electrochemical performances of the electrode materials.Li4Ti5O12,as a zero-strain material,has been considered as a promising anode material for long life Li-ion batteries.In this study,our results show that the Li4Ti5O12 pasted on Cu or graphite felt current collector exhibits unexpectedly higher rate performance than on Al current collector. For Li4Ti5O12,the electron transfer between current collector and active material is the critical factor that affects its rate and cycling performances.
基金supported by the National High Technology Research and Development Program of China (Grant No.2009AA033101)the National Basic Research Program of China (Grant No.2010CB833102)+2 种基金the National Natural Science Foundation of China (Grant No.50972164)the Chinese Academy of Sciences Project (Grant No.KJCX2-YW-W26)the Hundred-Talent Project of the Chinese Academy of Sciences
文摘This is the first time that a novel anode material,spinel (Li_4Ti_5O_(12)) which is well known as a "zero-strain" anode material for lithium storage,has been introduced for sodium-ion battery.The (Li_4Ti_5O_(12)) shows an average Na storage voltage of about 1.0 V and a reversible capacity of about 145 mAh/g,thereby making it a promising anode for sodiumion battery.Ex-situ X-ray diffraction (XRD) is used to investigate the structure change in the Na insertion/deinsertion process.Based on this,a possible Na storage mechanism is proposed.
基金supported by the National Natural Science Foundation of China(22179117 and U21A2075)the startup foundation for the Hundred-Talent Program of Zhejiang University.
文摘水系锌离子电池具有低成本、高安全的特点,有望应用于大规模储能.然而,锌负极的循环稳定性仍不理想,且水系电池缺少合适的亲水隔膜,这限制了水系锌离子电池的实际应用.在本文中,我们报道了一种可用于水系电池的分级多孔的聚偏二氟乙烯-双三氟甲磺酰亚胺锂(PVDF-LiTFSI)(PVDF-Li)隔膜.均匀混合的LiTFSI盐降低了PVDF的结晶性,使隔膜具有优异的机械强度,并形成分级的孔隙结构.这种LiTFSI诱导的分级多孔结构有助于实现Zn2+的快速传输和锌的均匀沉积,同时保证隔膜在水系电解液中具有优异的润湿性.这种先进的PVDF-Li隔膜能显著抑制锌枝晶的生长,提高水系锌离子电池的循环寿命.因此,使用PVDF-Li隔膜的Zn||V2O5电池的初始容量达324 mA h g-1,比传统玻璃纤维隔膜高27%,且容量保持率也得到大幅提升.该研究设计了一种功能隔膜来调控正负极反应的均匀性,这为高性能水系电池的开发提供了新的思路.
