以五氧化二钒干凝胶、碳酸锰、磷酸二氢铵、碳酸锂、乙炔黑为原料,采用固相法在相对较低的温度条件下合成了x Li Mn PO4·y Li3V2(PO4)3锂离子电池复合正极材料。采用X射线衍射(XRD)、扫描电镜(SEM)对其晶体结构和表面形貌进行表征...以五氧化二钒干凝胶、碳酸锰、磷酸二氢铵、碳酸锂、乙炔黑为原料,采用固相法在相对较低的温度条件下合成了x Li Mn PO4·y Li3V2(PO4)3锂离子电池复合正极材料。采用X射线衍射(XRD)、扫描电镜(SEM)对其晶体结构和表面形貌进行表征。结果表明,750℃下烧结15 h合成的3Li Mn PO4·Li3V2(PO4)3为结晶良好的两相结构,颗粒粒径较小且分布比较均匀,其在室温、0.2 C倍率下首次充放电容量分别为144.8 m Ah/g和139.8 m Ah/g,循环50次后容量为130.5 m Ah/g。展开更多
采用常规的固相反应法结合机械球磨制备了含碳质量分数23.7%的Li_(2)Ni_(2)(MoO_(4))3@C复合材料,并应用于锂离子电池负极。与纯Li_(2)Ni_(2)(MoO_(4))3相比,Li_(2)Ni_(2)(MoO_(4))3@C具有优异的电化学性能,在电流密度为200 mA ·g^...采用常规的固相反应法结合机械球磨制备了含碳质量分数23.7%的Li_(2)Ni_(2)(MoO_(4))3@C复合材料,并应用于锂离子电池负极。与纯Li_(2)Ni_(2)(MoO_(4))3相比,Li_(2)Ni_(2)(MoO_(4))3@C具有优异的电化学性能,在电流密度为200 mA ·g^(-1)时,50周循环后,可逆容量高达845 mAh·g^(-1)。值得注意的是,Li_(2)Ni_(2)(MoO_(4))3@C的首周库仑效率高达85%。此外,运用循环伏安法对Li_(2)Ni_(2)(MoO_(4))3@C复合物存储锂行为进行了初步探索。展开更多
Fast charging and high-power delivering batteries are highly demanded in mobile electronics,electric vehicles and grid energy storage,but there are full of challenges.The star-material Li_(3)V_(2)(PO_(4))_(3) is demon...Fast charging and high-power delivering batteries are highly demanded in mobile electronics,electric vehicles and grid energy storage,but there are full of challenges.The star-material Li_(3)V_(2)(PO_(4))_(3) is demonstrated as a promising high-rate cathode material meeting the above requirements.Herein,we report the carbon decorated Li_(3)V_(2)(PO_(4))_(3) (LVP/C) cathode prepared via a facile method,which displays a remarkable high-rate capability and long-term cycling performance.Briefly,the prepared LVP/C delivers a high discharge capacity of 122 mAh g^(-1)(-93% of the theoretical capacity) at a high rate up to 20 C and a superior capacity retention of 87.1% after 1000 cycles.Importantly,by applying a combination of X-ray absorption spectroscopy and full-range mapping of resonant inelastic X-ray scattering,we clearly elucidate the structural and chemical evolutions of LVP upon various potentials and cycle numbers.We show unambiguous spectroscopic evidences that the evolution of the hybridization strength between V and O in LVP/C as a consequence of lithiation/delithiation is highly reversible both in the bulk and on the surface during the discharge-charge processes even over extended cycles,which should be responsible for the remarkable electrochemical performance of LVP/C.Our present study provides not only an effective synthesis strategy but also deeper insights into the surface and bulk electrochemical reaction mechanism of LVP,which should be beneficial for the further design of high-performance LVP electrode materials.展开更多
Lithium(Li)-rich manganese(Mn)-based cathode Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_(2)(LRNCM)has attracted considerable attention owing to its high specific discharge capacity and low cost.However,unsatisfactory cycle ...Lithium(Li)-rich manganese(Mn)-based cathode Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_(2)(LRNCM)has attracted considerable attention owing to its high specific discharge capacity and low cost.However,unsatisfactory cycle performance and poor rate property hinder its large-scale application.The fast ionic conductor has been widely used as the cathode coating material because of its superior stability and excellent lithium-ion conductivity rate.In this study,Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_(2) is modified by using Li_(1.4)Al_(0.4)Ti_(1.6)(PO_(4))_(3)(LATP)ionic conductor.The electrochemical test results show that the discharge capacity of the resulting LRNCM@LATP1 sample is 198 mA·h/g after 100 cycles at 0.2C,with a capacity retention of 81%.Compared with the uncoated pristine LRNCM(188.4 m A·h/g and 76%),LRNCM after the LATP modification shows superior cycle performance.Moreover,the lithium-ion diffusion coefficient D_(Li+)is a crucial factor affecting the rate performance,and the D_(Li+)of the LRNCM material is improved from 4.94×10^(-13) to 5.68×10^(-12)cm^(2)/s after modification.The specific capacity of LRNCM@LATP1 reaches 102.5 mA·h/g at 5C,with an improved rate performance.Thus,the modification layer can considerably enhance the electrochemical performance of LRNCM.展开更多
The poor contact and side reactions between Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)and lithium(Li)anode cause uneven Li plating and high interfacial impendence,which greatly hinder the practical application of LATP...The poor contact and side reactions between Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)and lithium(Li)anode cause uneven Li plating and high interfacial impendence,which greatly hinder the practical application of LATP in high-energy density solid-state Li metal batteries.In this work,a multifunctional ferroelectric BaTiO_(3)(BTO)/poly(vinylidene fluoride-co-trifluoroethylene-co-chlorotrifluoroethylene)(P[VDF-TrFE-CTFE])composite interlayer(B-TERB)is constructed between LATP and Li metal anode,which not only suppresses the Li dendrite growth,but also improves the interfacial stability and maintains the intimate interfacial contact to significantly decrease the interfacial resistance by two orders of magnitude.The B-TERB interlayer generates a uniform electric field to induce a uniform and lateral Li deposition,and therefore avoids the side reactions between Li metal and LATP achieving excellent interface stability.As a result,the Li/LATP@B-TERB/Li symmetrical batteries can stably cycle for 1800 h at 0.2 mA cm^(-2)and 1000 h at 0.5 mA cm^(-2).The solid-state LiFePO_(4)/LATP@B-TERB/Li full batteries also exhibit excellent cycle performance for 250 cycles at 0.5 C and room temperature.This work proposes a novel strategy to design multifunctional ferroelectric interlayer between ceramic electrolytes and Li metal to enable stable room-temperature cycling performance.展开更多
文摘以五氧化二钒干凝胶、碳酸锰、磷酸二氢铵、碳酸锂、乙炔黑为原料,采用固相法在相对较低的温度条件下合成了x Li Mn PO4·y Li3V2(PO4)3锂离子电池复合正极材料。采用X射线衍射(XRD)、扫描电镜(SEM)对其晶体结构和表面形貌进行表征。结果表明,750℃下烧结15 h合成的3Li Mn PO4·Li3V2(PO4)3为结晶良好的两相结构,颗粒粒径较小且分布比较均匀,其在室温、0.2 C倍率下首次充放电容量分别为144.8 m Ah/g和139.8 m Ah/g,循环50次后容量为130.5 m Ah/g。
文摘采用常规的固相反应法结合机械球磨制备了含碳质量分数23.7%的Li_(2)Ni_(2)(MoO_(4))3@C复合材料,并应用于锂离子电池负极。与纯Li_(2)Ni_(2)(MoO_(4))3相比,Li_(2)Ni_(2)(MoO_(4))3@C具有优异的电化学性能,在电流密度为200 mA ·g^(-1)时,50周循环后,可逆容量高达845 mAh·g^(-1)。值得注意的是,Li_(2)Ni_(2)(MoO_(4))3@C的首周库仑效率高达85%。此外,运用循环伏安法对Li_(2)Ni_(2)(MoO_(4))3@C复合物存储锂行为进行了初步探索。
基金supported by Collaborative Innovation Center of Suzhou Nano Science & Technologythe Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)+5 种基金the 111 roject, Joint International Research Laboratory of Carbon-Based Functional Materials and Devicesthe National Natural Science Foundation of China (11905154)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (19KJA550004)the Natural Science Foundation of Jiangsu Province (BK20190814)the National Key R&D Program of China (No. 2016YFA0202600)supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231。
文摘Fast charging and high-power delivering batteries are highly demanded in mobile electronics,electric vehicles and grid energy storage,but there are full of challenges.The star-material Li_(3)V_(2)(PO_(4))_(3) is demonstrated as a promising high-rate cathode material meeting the above requirements.Herein,we report the carbon decorated Li_(3)V_(2)(PO_(4))_(3) (LVP/C) cathode prepared via a facile method,which displays a remarkable high-rate capability and long-term cycling performance.Briefly,the prepared LVP/C delivers a high discharge capacity of 122 mAh g^(-1)(-93% of the theoretical capacity) at a high rate up to 20 C and a superior capacity retention of 87.1% after 1000 cycles.Importantly,by applying a combination of X-ray absorption spectroscopy and full-range mapping of resonant inelastic X-ray scattering,we clearly elucidate the structural and chemical evolutions of LVP upon various potentials and cycle numbers.We show unambiguous spectroscopic evidences that the evolution of the hybridization strength between V and O in LVP/C as a consequence of lithiation/delithiation is highly reversible both in the bulk and on the surface during the discharge-charge processes even over extended cycles,which should be responsible for the remarkable electrochemical performance of LVP/C.Our present study provides not only an effective synthesis strategy but also deeper insights into the surface and bulk electrochemical reaction mechanism of LVP,which should be beneficial for the further design of high-performance LVP electrode materials.
基金Project(51772333) supported by the National Natural Science Foundation of China。
文摘Lithium(Li)-rich manganese(Mn)-based cathode Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_(2)(LRNCM)has attracted considerable attention owing to its high specific discharge capacity and low cost.However,unsatisfactory cycle performance and poor rate property hinder its large-scale application.The fast ionic conductor has been widely used as the cathode coating material because of its superior stability and excellent lithium-ion conductivity rate.In this study,Li_(1.2)Ni_(0.13)Co_(0.13)Mn_(0.54)O_(2) is modified by using Li_(1.4)Al_(0.4)Ti_(1.6)(PO_(4))_(3)(LATP)ionic conductor.The electrochemical test results show that the discharge capacity of the resulting LRNCM@LATP1 sample is 198 mA·h/g after 100 cycles at 0.2C,with a capacity retention of 81%.Compared with the uncoated pristine LRNCM(188.4 m A·h/g and 76%),LRNCM after the LATP modification shows superior cycle performance.Moreover,the lithium-ion diffusion coefficient D_(Li+)is a crucial factor affecting the rate performance,and the D_(Li+)of the LRNCM material is improved from 4.94×10^(-13) to 5.68×10^(-12)cm^(2)/s after modification.The specific capacity of LRNCM@LATP1 reaches 102.5 mA·h/g at 5C,with an improved rate performance.Thus,the modification layer can considerably enhance the electrochemical performance of LRNCM.
基金supported by National Natural Science Foundation of China(No.U2001220)Local Innovative Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01N111)+1 种基金Shenzhen All-Solid-State Lithium Battery Electrolyte Engineering Research Center(XMHT20200203006)Shenzhen Technical Plan Project(Nos.RCJC20200714114436091,JCYJ20180508152210821,and JCYJ20180508152135822).
文摘The poor contact and side reactions between Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)and lithium(Li)anode cause uneven Li plating and high interfacial impendence,which greatly hinder the practical application of LATP in high-energy density solid-state Li metal batteries.In this work,a multifunctional ferroelectric BaTiO_(3)(BTO)/poly(vinylidene fluoride-co-trifluoroethylene-co-chlorotrifluoroethylene)(P[VDF-TrFE-CTFE])composite interlayer(B-TERB)is constructed between LATP and Li metal anode,which not only suppresses the Li dendrite growth,but also improves the interfacial stability and maintains the intimate interfacial contact to significantly decrease the interfacial resistance by two orders of magnitude.The B-TERB interlayer generates a uniform electric field to induce a uniform and lateral Li deposition,and therefore avoids the side reactions between Li metal and LATP achieving excellent interface stability.As a result,the Li/LATP@B-TERB/Li symmetrical batteries can stably cycle for 1800 h at 0.2 mA cm^(-2)and 1000 h at 0.5 mA cm^(-2).The solid-state LiFePO_(4)/LATP@B-TERB/Li full batteries also exhibit excellent cycle performance for 250 cycles at 0.5 C and room temperature.This work proposes a novel strategy to design multifunctional ferroelectric interlayer between ceramic electrolytes and Li metal to enable stable room-temperature cycling performance.
