Huge volume changes of Si during lithiation/delithiation lead to regeneration of solid-electrolyte interphase(SEI)and consume electrolyte.In this article,γ-glycidoxypropyl trimethoxysilane(GOPS)was incorporated in Si...Huge volume changes of Si during lithiation/delithiation lead to regeneration of solid-electrolyte interphase(SEI)and consume electrolyte.In this article,γ-glycidoxypropyl trimethoxysilane(GOPS)was incorporated in Si/PEDOT:PSS electrodes to construct a flexible and conductive artificial SEI,effectively suppressing the consumption of electrolyte.The optimized electrode can maintain 1000 mAh g^−1 for nearly 800 cycles under limited electrolyte compared with 40 cycles of the electrodes without GOPS.Also,the optimized electrode exhibits excellent rate capability.The use of GOPS greatly improves the interface compatibility between Si and PEDOT:PSS.XPS Ar+etching depth analysis proved that the addition of GOPS is conducive to forming a more stable SEI.A full battery assembled with NCM 523 cathode delivers a high energy density of 520 Wh kg^−1,offering good stability.展开更多
Silicon is a low price and high capacity ancxje material for lithium-ion batteries.The yolk-shell structure can effectively accommodate Si expansion to improve stability.However,the limited rate performance of Si anod...Silicon is a low price and high capacity ancxje material for lithium-ion batteries.The yolk-shell structure can effectively accommodate Si expansion to improve stability.However,the limited rate performance of Si anodes can't meet people's growing demand for high power density.Herein,the phosphorus-doped yolk-shell Si@C materials(P-doped Si@C)were prepared through carbon coating on P-doped Si/SiO_(x)matrix to obtain high power and stable devices.Therefore,the as-prepared P-doped Si@C electrodes delivered a rapid increase in Coulombic efficiency from 74.4%to 99.6%after only 6 cycles,high capacity retention of-95%over 800 cycles at 4 A·g^(-1),and great rate capability(510 mAh·g^(-1)at 35 A·g^(-1)).As a result,P-doped Si@C anodes paired with commercial activated carbon and LiFePO_(4)cathode to assemble lithium-ion capacitor(high power density of〜61,080 W·kg^(-1)at 20 A·g^(-1))and lithium-ion full cell(good rate performance with 68.3 mAh·g^(-1)at 5 C),respectively.This work can provide an effective way tofurther improve power density and stability for energy storage devices.展开更多
基金The work is supported by Science and Technology Commission of Shanghai Municipality(20520710400)National Natural Science Foundation of China(21771124)+1 种基金Oceanic Interdisciplinary Program(project number SL2020MS020)SJTU-Warwick Joint Seed Fund(2019/20)of Shanghai Jiao Tong University.
文摘Huge volume changes of Si during lithiation/delithiation lead to regeneration of solid-electrolyte interphase(SEI)and consume electrolyte.In this article,γ-glycidoxypropyl trimethoxysilane(GOPS)was incorporated in Si/PEDOT:PSS electrodes to construct a flexible and conductive artificial SEI,effectively suppressing the consumption of electrolyte.The optimized electrode can maintain 1000 mAh g^−1 for nearly 800 cycles under limited electrolyte compared with 40 cycles of the electrodes without GOPS.Also,the optimized electrode exhibits excellent rate capability.The use of GOPS greatly improves the interface compatibility between Si and PEDOT:PSS.XPS Ar+etching depth analysis proved that the addition of GOPS is conducive to forming a more stable SEI.A full battery assembled with NCM 523 cathode delivers a high energy density of 520 Wh kg^−1,offering good stability.
基金Science and Technology Commission of Shanghai Municipality(Nos.20520710400,18230743400,18QA1402400)the National Natural Science Foundation of China(No.21771124)+1 种基金Oceanic Interdisciplinary Program of Shanghai Jiao Tong University(No.SL2020MS020)SJTU-Warwick Joint Seed Fund(2019/20).
文摘Silicon is a low price and high capacity ancxje material for lithium-ion batteries.The yolk-shell structure can effectively accommodate Si expansion to improve stability.However,the limited rate performance of Si anodes can't meet people's growing demand for high power density.Herein,the phosphorus-doped yolk-shell Si@C materials(P-doped Si@C)were prepared through carbon coating on P-doped Si/SiO_(x)matrix to obtain high power and stable devices.Therefore,the as-prepared P-doped Si@C electrodes delivered a rapid increase in Coulombic efficiency from 74.4%to 99.6%after only 6 cycles,high capacity retention of-95%over 800 cycles at 4 A·g^(-1),and great rate capability(510 mAh·g^(-1)at 35 A·g^(-1)).As a result,P-doped Si@C anodes paired with commercial activated carbon and LiFePO_(4)cathode to assemble lithium-ion capacitor(high power density of〜61,080 W·kg^(-1)at 20 A·g^(-1))and lithium-ion full cell(good rate performance with 68.3 mAh·g^(-1)at 5 C),respectively.This work can provide an effective way tofurther improve power density and stability for energy storage devices.
