With the number of decommissioned electric vehicles increasing annually,a large amount of discarded power battery cathode material is in urgent need of treatment.However,common leaching methods for recovering metal sa...With the number of decommissioned electric vehicles increasing annually,a large amount of discarded power battery cathode material is in urgent need of treatment.However,common leaching methods for recovering metal salts are economically inefficient and polluting.Meanwhile,the recycled material obtained by lithium remediation alone has limited performance in cycling stability.Herein,a short method of solid-phase reduction is developed to recover spent LiFePO4 by simultaneously introducing Mg2+ions for hetero-atom doping.Issues of particle agglomeration,carbon layer breakage,lithium loss,and Fe3+defects in spent LiFePO4 are also addressed.Results show that Mg2+addition during regeneration can remarkably enhance the crystal structure stability and improve the Li+diffusion coefficient.The regenerated LiFePO4 exhibits significantly improved electrochemical performance with a specific discharge capacity of 143.2 mAh·g^(−1)at 0.2 C,and its capacity retention is extremely increased from 37.9%to 98.5%over 200 cycles at 1 C.Especially,its discharge capacity can reach 95.5 mAh·g^(−1)at 10 C,which is higher than that of spent LiFePO4(55.9 mAh·g^(−1)).All these results show that the proposed regeneration strategy of simultaneous carbon coating and Mg2+doping is suitable for the efficient treatment of spent LiFePO4.展开更多
The LiFePO4 nanotubes were successfully fabricated by a sol-gel method with porous anodic aluminum oxide as the template. Transmission electron microscopy and scanning electron microscopy showed that the synthesized L...The LiFePO4 nanotubes were successfully fabricated by a sol-gel method with porous anodic aluminum oxide as the template. Transmission electron microscopy and scanning electron microscopy showed that the synthesized LiFeP04 nanotubes were monodispersed and parallel to one another. Selected area electron diffraction pattern, X-ray diffraction and X-ray photoelectron spectroscopy investigations jointly demonstrated that the synthesized LiFePO4 nanotubes were pure olivine structure. This approach offered a potentially way for fabricating ordered LiFePO4 nanotubes at room temperature and ambient conditions, which might be expected to find promising application as a new cathode material in lithium ion battery,展开更多
基金supported by the Science and Technology Innovation Program of Hunan Province(No.2020SK2007)the Natural Science Foundation of Hunan Province(No.2019JJ50814)+2 种基金the Fundamental Research Funds for the Central Universities of Central South University(No.1053320211765)the Science and Technology Planning Project of Guangdong Province of China(No.2017B030314046)Guangdong Academy of Sciences for Innovation Capacity Building(No.2016GDASRC0201).
文摘With the number of decommissioned electric vehicles increasing annually,a large amount of discarded power battery cathode material is in urgent need of treatment.However,common leaching methods for recovering metal salts are economically inefficient and polluting.Meanwhile,the recycled material obtained by lithium remediation alone has limited performance in cycling stability.Herein,a short method of solid-phase reduction is developed to recover spent LiFePO4 by simultaneously introducing Mg2+ions for hetero-atom doping.Issues of particle agglomeration,carbon layer breakage,lithium loss,and Fe3+defects in spent LiFePO4 are also addressed.Results show that Mg2+addition during regeneration can remarkably enhance the crystal structure stability and improve the Li+diffusion coefficient.The regenerated LiFePO4 exhibits significantly improved electrochemical performance with a specific discharge capacity of 143.2 mAh·g^(−1)at 0.2 C,and its capacity retention is extremely increased from 37.9%to 98.5%over 200 cycles at 1 C.Especially,its discharge capacity can reach 95.5 mAh·g^(−1)at 10 C,which is higher than that of spent LiFePO4(55.9 mAh·g^(−1)).All these results show that the proposed regeneration strategy of simultaneous carbon coating and Mg2+doping is suitable for the efficient treatment of spent LiFePO4.
基金supported by tile National Natural Science Foundation of China(No.50375151,No.50323007 and No.50572107)863 Program(No.2002AA302609)"Hundreds Talent Program"of Chinese Academy of Sciences for financial Support.
文摘The LiFePO4 nanotubes were successfully fabricated by a sol-gel method with porous anodic aluminum oxide as the template. Transmission electron microscopy and scanning electron microscopy showed that the synthesized LiFeP04 nanotubes were monodispersed and parallel to one another. Selected area electron diffraction pattern, X-ray diffraction and X-ray photoelectron spectroscopy investigations jointly demonstrated that the synthesized LiFePO4 nanotubes were pure olivine structure. This approach offered a potentially way for fabricating ordered LiFePO4 nanotubes at room temperature and ambient conditions, which might be expected to find promising application as a new cathode material in lithium ion battery,
