Constructing tri-functional modification for spinel LiNi0.5Mn1.5O4 via fast ion conductor

JOURNAL OF POWER SOURCES

卷:450

Article

Li, Li¹  Zhao, Rui¹  Pan, Du¹  Yi, Shuhong¹  Gao, Liufei¹  He, Guanjie³  Zhao, Huiling¹  Yu, Caiyan^1,2  Bai, Ying¹ 

[1] Henan Univ, Sch Phys & Elect, Kaifeng 475004, Peoples R China

[2] Henan Univ, Natl Demonstrat Ctr Expt Phys & Elect Educ, Sch Phys & Elect, Kaifeng 475004, Peoples R China

[3] UCL Dept Chem, Mat Res Ctr, Christopher Ingold Bldg,20 Gordon St, London WC1H 0AJ, England

关键词: Lithium-ion batteries;    LiNi0.5Mn1.5O4;    Li6.4La3Al0.2Zr2O12;    Tri-functional modification;   

DOI  :  10.1016/j.jpowsour.2019.227677

来源: Elsevier

【 摘 要 】

Instable surface structure and low capacity retention hinder the further application of high voltage LiNi0.5Mn1.5O4 (LNMO) cathode in lithium-ion battery. In order to promote its electrochemical performances, Li6.4La3Al0.2Zr2O12 (LLAZO) with the intrinsic property of fast ion conductivity has been employed as a protective layer to modify surface of LNMO. By regulating the LLAZO contents, 1 wt % LLAZO coated LNMO (LLAZO-1) cathode shows a high capacity of 92.1 mAh g(-1) over 600 cycles with a capacity retention of 72.6% at 1 C and a reversible capacity of 57.9 mAh g(-1) at 20 C, much higher than those of pristine LNMO. Further investigation indicates that the greatly improved electrochemical performances of LLAZO-1 can be attributed to the LLAZO modification, which including the LLAZO surface coating and La3+ and Zr4- gradient co-doping. In addition, the LLAZO precursor significantly restricts the growth of LNMO precursor particles during calcination process, shorting Li+ migration pathway. Thus, modification strategy effectively improves the structure stability of LNMO, accompanied with the enhancement in lithium-ion diffusion kinetics performances and confinement in particle growth. This optimization approach with tri-functions sheds light on novel electrode design and construction in rechargeable batteries.

【 授权许可】

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