Ni-rich layered oxides are considered promising cathodes for advanced lithium-ion batteries(LIBs)in the future,owing to their high capacity and low cost.However,the issues on structural and interfacial stability of Ni...Ni-rich layered oxides are considered promising cathodes for advanced lithium-ion batteries(LIBs)in the future,owing to their high capacity and low cost.However,the issues on structural and interfacial stability of Ni-rich cathodes still pose substantial obstacles in the practical application of advanced LIBs.Here,we employ a one-step method to synthesize a B-doped and La_(4)NiLiO_(8)-coated LiNi_(0.82)5Co_(0.115)Mn_(0.06)O_(2)(BL-1)cathode with reliable structure and interface,for the first time.The La_(4)NiLiO_(8)coating layer can prevent cathodes from electrolyte assault and facilitate Li+diffusion kinetics.Moreover,B-doping can effectively restrain the pernicious H_(2)-H_(3) phase transition and adjust the orientation of primary particles to a radial alignment,which is obstructive to the arise of microcracks induced by the change of anisotropic volume.Specifically,when tested in pouch cells,the BL-1 cathode exhibits outstanding capacity retention of 93.49%after 500 cycles at 1 C.This dual-modification strategy dramatically enhances the stability of the structure and interface for Ni-rich cathode materials,consequently accelerating the commercialization process of high-energy–density LIBs.展开更多
Zinc-ion batteries(ZIBs)is a promising electrical energy storage candidate due to its eco-friendliness,low cost,and intrinsic safety,but on the cathode the element dissolution and the formation of irreversible product...Zinc-ion batteries(ZIBs)is a promising electrical energy storage candidate due to its eco-friendliness,low cost,and intrinsic safety,but on the cathode the element dissolution and the formation of irreversible products,and on the anode the growth of dendrite as well as irreversible products hinder its practical application.Herein,we propose a new type of the inorganic highly concentrated colloidal electrolytes(HCCE)for ZIBs promoting simultaneous robust protection of both cathode/anode leading to an effective suppression of element dissolution,dendrite,and irreversible products growth.The new HCCE has high Zn^(2+)ion transference number(0.64)endowed by the limitation of SO4^(2−),the competitive ion conductivity(1.1×10^(–2) S cm^(−1))and Zn2+ion diffusion enabled by the uniform pore distribution(3.6 nm)and the limited free water.The Zn/HCCE/α-MnO2 cells exhibit high durability under both high and low current densities,which is almost 100%capacity retention at 200 mA g^(−1) after 400 cycles(290 mAh g^(−1))and 89%capacity retention under 500 mA g^(−1) after 1000 cycles(212 mAh g^(−1)).Considering material sustainability and batteries’high performances,the colloidal electrolyte may provide a feasible substitute beyond the liquid and all-solid-state electrolyte of ZIBs.展开更多
Fe3O4 is a promising high-capacity anode material for lithium ion batteries, but challenges including short cycle life and low rate capability hinder its widespread implementation. In this work, a well-defined tubular...Fe3O4 is a promising high-capacity anode material for lithium ion batteries, but challenges including short cycle life and low rate capability hinder its widespread implementation. In this work, a well-defined tubular structure constructed by carbon-coated Fe3O4 has been successfully fabricated with hierarchically porous structure, high surface area, and suitable thickness of carbon layer. Such purposely designed hybrid nanostructures have an enhanced electronic/ionic conductivity, stable electrode/electrolyte interface, and physical buffering effect arising from the nanoscale combination of carbon with Fe3O4, as well as the hollow, aligned and hierarchically porous architectures. When used as an anode material for a lithium-ion half cell, the carbon-coated hierarchical Fe3O4 nanotubes showed excellent cycling performance with a specific capacity of 1,020 mAh.g^-1 at 200 mA.g^-1 after 150 cycles, a capacity retention of ca. 103%. Even at a higher current density of 1,000 mA·g^-1, a capacity of 840 mAh·g^-1 is retained after 300 cycles with no capacity loss. In particular, a superior rate capability can be obtained with a stable capacity of 355 mAh.g^-1 at 8,000 mA·g^-1. The encouraging results indicate that hierarchically tubular hybrid nanostructures can have important implications for the development of high-rate electrodes for future rechargeable lithium ion batteries （LIBs）.展开更多
A flexible asymmetric supercapacitor(ASC)based on a Co Al-layered double hydroxide(Co Al-LDH)electrode and a reduced graphene oxide(r GO) electrode was successfully fabricated. The Co Al-LDH electrode as a positive el...A flexible asymmetric supercapacitor(ASC)based on a Co Al-layered double hydroxide(Co Al-LDH)electrode and a reduced graphene oxide(r GO) electrode was successfully fabricated. The Co Al-LDH electrode as a positive electrode was synthesized by directly growing Co Al-LDH nanosheet arrays on a carbon cloth(CC)through a facile hydrothermal method, and it delivered a specific capacitance of 616.9 F g^(-1)at a current density of1 A g^(-1). The r GO electrode as a negative electrode was synthesized by coating r GO on the CC via a simple dipcoating method and revealed a specific capacitance of110.0 F g^(-1)at a current density of 2 A g^(-1). Ultimately,the advanced ASC offered a broad voltage window(1.7 V)and exhibited a high superficial capacitance of1.77 F cm^(-2)at 2 m A cm^(-2)and a high energy density of0.71 m Wh cm^(-2)at a power density of 17.05 m W cm^(-2),along with an excellent cycle stability(92.9% capacitance retention over 8000 charge–discharge cycles).展开更多
基金financially supported by the National Natural Science Foundation of China(51774051,52072323,52122211)the Science and Technology Planning Project of Hunan Province(2019RS2034)+1 种基金the Hunan High-tech Industry Science and Technology Innovation Leading Plan(2020GK2072)the Changsha City Fund for Distinguished and Innovative Young Scholars(KQ1707014)。
文摘Ni-rich layered oxides are considered promising cathodes for advanced lithium-ion batteries(LIBs)in the future,owing to their high capacity and low cost.However,the issues on structural and interfacial stability of Ni-rich cathodes still pose substantial obstacles in the practical application of advanced LIBs.Here,we employ a one-step method to synthesize a B-doped and La_(4)NiLiO_(8)-coated LiNi_(0.82)5Co_(0.115)Mn_(0.06)O_(2)(BL-1)cathode with reliable structure and interface,for the first time.The La_(4)NiLiO_(8)coating layer can prevent cathodes from electrolyte assault and facilitate Li+diffusion kinetics.Moreover,B-doping can effectively restrain the pernicious H_(2)-H_(3) phase transition and adjust the orientation of primary particles to a radial alignment,which is obstructive to the arise of microcracks induced by the change of anisotropic volume.Specifically,when tested in pouch cells,the BL-1 cathode exhibits outstanding capacity retention of 93.49%after 500 cycles at 1 C.This dual-modification strategy dramatically enhances the stability of the structure and interface for Ni-rich cathode materials,consequently accelerating the commercialization process of high-energy–density LIBs.
基金National Natural Science Foundation of China(Grant Nos.51972346,51932011,51922038,and 51672078)Hunan Outstanding Youth Talents(No.2019JJ20005)+1 种基金the Program of Youth Talent Support for Hunan Province(2020RC3011)Innovation-Driven Project of Central South University(No.2020CX024).
文摘Zinc-ion batteries(ZIBs)is a promising electrical energy storage candidate due to its eco-friendliness,low cost,and intrinsic safety,but on the cathode the element dissolution and the formation of irreversible products,and on the anode the growth of dendrite as well as irreversible products hinder its practical application.Herein,we propose a new type of the inorganic highly concentrated colloidal electrolytes(HCCE)for ZIBs promoting simultaneous robust protection of both cathode/anode leading to an effective suppression of element dissolution,dendrite,and irreversible products growth.The new HCCE has high Zn^(2+)ion transference number(0.64)endowed by the limitation of SO4^(2−),the competitive ion conductivity(1.1×10^(–2) S cm^(−1))and Zn2+ion diffusion enabled by the uniform pore distribution(3.6 nm)and the limited free water.The Zn/HCCE/α-MnO2 cells exhibit high durability under both high and low current densities,which is almost 100%capacity retention at 200 mA g^(−1) after 400 cycles(290 mAh g^(−1))and 89%capacity retention under 500 mA g^(−1) after 1000 cycles(212 mAh g^(−1)).Considering material sustainability and batteries’high performances,the colloidal electrolyte may provide a feasible substitute beyond the liquid and all-solid-state electrolyte of ZIBs.
文摘Fe3O4 is a promising high-capacity anode material for lithium ion batteries, but challenges including short cycle life and low rate capability hinder its widespread implementation. In this work, a well-defined tubular structure constructed by carbon-coated Fe3O4 has been successfully fabricated with hierarchically porous structure, high surface area, and suitable thickness of carbon layer. Such purposely designed hybrid nanostructures have an enhanced electronic/ionic conductivity, stable electrode/electrolyte interface, and physical buffering effect arising from the nanoscale combination of carbon with Fe3O4, as well as the hollow, aligned and hierarchically porous architectures. When used as an anode material for a lithium-ion half cell, the carbon-coated hierarchical Fe3O4 nanotubes showed excellent cycling performance with a specific capacity of 1,020 mAh.g^-1 at 200 mA.g^-1 after 150 cycles, a capacity retention of ca. 103%. Even at a higher current density of 1,000 mA·g^-1, a capacity of 840 mAh·g^-1 is retained after 300 cycles with no capacity loss. In particular, a superior rate capability can be obtained with a stable capacity of 355 mAh.g^-1 at 8,000 mA·g^-1. The encouraging results indicate that hierarchically tubular hybrid nanostructures can have important implications for the development of high-rate electrodes for future rechargeable lithium ion batteries （LIBs）.
基金supported by National Natural Science Foundation of China(21376105 and 21576113)Foshan Innovative and Entepreneurial Research Team Program(No.2014IT100062)
文摘A flexible asymmetric supercapacitor(ASC)based on a Co Al-layered double hydroxide(Co Al-LDH)electrode and a reduced graphene oxide(r GO) electrode was successfully fabricated. The Co Al-LDH electrode as a positive electrode was synthesized by directly growing Co Al-LDH nanosheet arrays on a carbon cloth(CC)through a facile hydrothermal method, and it delivered a specific capacitance of 616.9 F g^(-1)at a current density of1 A g^(-1). The r GO electrode as a negative electrode was synthesized by coating r GO on the CC via a simple dipcoating method and revealed a specific capacitance of110.0 F g^(-1)at a current density of 2 A g^(-1). Ultimately,the advanced ASC offered a broad voltage window(1.7 V)and exhibited a high superficial capacitance of1.77 F cm^(-2)at 2 m A cm^(-2)and a high energy density of0.71 m Wh cm^(-2)at a power density of 17.05 m W cm^(-2),along with an excellent cycle stability(92.9% capacitance retention over 8000 charge–discharge cycles).
