Composite Si@SiO_(x)/C anodes with high specific capacity are considered the most promising alternatives to graphite in industrial lithium-ion batteries.However,their cycling stability remains a limiting factor,which ...Composite Si@SiO_(x)/C anodes with high specific capacity are considered the most promising alternatives to graphite in industrial lithium-ion batteries.However,their cycling stability remains a limiting factor,which originates from the severe volume deformation of silicon-derived species.In this work,the cyclabilities of composite anodes are improved by unshackling the highly reversible lithium storage capabilities from the redundancy capacity of the anode materials.A selective LiF-induced lithiation strategy is proposed based on exploiting interface separation energy differences between LiF and the active materials.An interesting preferential redeposition of LiF is observed at the Si@SiO_(x) particles,which differentiates the otherwise similar lithiation potentials of LiC_(x) and Li_(15)Si_(4),thereby enabling lithium storage in graphite that was previously underused.The resulting full cell exhibits better rate and cycling performances without sacrificing specific capacity.In an ultra-high area capacity full cell(4.9 mA h cm^(-2)),the capacity retention increases markedly from 66.1% to 94.2% after 300 cycles.The selective lithiation strategy developed herein is feasible for practical industrial applications,and importantly,it requires no changes to the existing mature lithium-ion battery manufacturing process.This study offers a new approach for the development of silicon/graphite composite anodes with long cycling lifetimes.展开更多
Germanium based sulfides are potentially attractive as anode material for sodium ion batteries but rarely investigated. Herein, we firstly investigated Na^+storage properties of pristine Cu2GeS3(PCGS) and found an ...Germanium based sulfides are potentially attractive as anode material for sodium ion batteries but rarely investigated. Herein, we firstly investigated Na^+storage properties of pristine Cu2GeS3(PCGS) and found an effective strategy to improve its performance by a single lithiation/delithiation cycle obtaining ultrafine nanoparticle copper germanium sulfide(NCGS). The lithiation/delithiation process leads to the formation of a stable Li-containing solid electrolyte interphase film and a significant improvement of sodiation kinetics. Therefore, the NCGS anode delivers favorable capacity retention and better rate capability compared with that of a PCGS whether in the half cell or in the full cell,showing great promise for energy storage application.展开更多
基金supported by the Key-Area Research and Development Program of Guangdong Province(2020B090919005)the National Key R&D Program of China(2017YFE0127600)+3 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA22010600)Taishan Scholars Program for Young Expert of Shandong Province(tsqn 202103145)the National Natural Science Foundation of China(22179135)the Finance Science and Technology Project of Hainan province(ZDKJ202014)。
文摘Composite Si@SiO_(x)/C anodes with high specific capacity are considered the most promising alternatives to graphite in industrial lithium-ion batteries.However,their cycling stability remains a limiting factor,which originates from the severe volume deformation of silicon-derived species.In this work,the cyclabilities of composite anodes are improved by unshackling the highly reversible lithium storage capabilities from the redundancy capacity of the anode materials.A selective LiF-induced lithiation strategy is proposed based on exploiting interface separation energy differences between LiF and the active materials.An interesting preferential redeposition of LiF is observed at the Si@SiO_(x) particles,which differentiates the otherwise similar lithiation potentials of LiC_(x) and Li_(15)Si_(4),thereby enabling lithium storage in graphite that was previously underused.The resulting full cell exhibits better rate and cycling performances without sacrificing specific capacity.In an ultra-high area capacity full cell(4.9 mA h cm^(-2)),the capacity retention increases markedly from 66.1% to 94.2% after 300 cycles.The selective lithiation strategy developed herein is feasible for practical industrial applications,and importantly,it requires no changes to the existing mature lithium-ion battery manufacturing process.This study offers a new approach for the development of silicon/graphite composite anodes with long cycling lifetimes.
基金National Natural Science Foundation of China (51502319)Shandong Provincial Natural Science Foundation (BS2015CL014)the Think-Tank Mutual Fund of Qingdao Energy Storage Industry Scientific Research and Qingdao Key Lab of Solar Energy Utilization and Energy Storage Technology
文摘Germanium based sulfides are potentially attractive as anode material for sodium ion batteries but rarely investigated. Herein, we firstly investigated Na^+storage properties of pristine Cu2GeS3(PCGS) and found an effective strategy to improve its performance by a single lithiation/delithiation cycle obtaining ultrafine nanoparticle copper germanium sulfide(NCGS). The lithiation/delithiation process leads to the formation of a stable Li-containing solid electrolyte interphase film and a significant improvement of sodiation kinetics. Therefore, the NCGS anode delivers favorable capacity retention and better rate capability compared with that of a PCGS whether in the half cell or in the full cell,showing great promise for energy storage application.