三元材料包覆改性.doc

三元材料包覆改性.docContents lists available at ScienceDirect
Journal of Alloys and Compounds
ELSEVIER
journal homepage: v ie r. com /l oca te/j alc o m
Improve the structure and electrochemical performanee
of LiNi M n O2 cathode material by nano-Al 2O3 ultras onic coati ng
Yanping
Chen a, Yun Zhang a,?, Fu Wang b, Zongyi
Wang a, Qiang
Zhang
College of Materials
State Key Laboratory
Scienee and
Cultivati on
Engineering, Sichuan University, Chengdu 610065, PR China
Base for Non metal Composite and Fun cti onal Materials, Southwest
Un iversity
of Scie nee and Tech no logy, Mianyang
621010, PRChi na
art i c l e info
Article history:
Received 29 July 2013
Received in revised form 15 April 2014
Accepted 10 May 2014
Available online 22 May 2014
Keywords:
Lithium ion batteries
LiNi Co Mn O2
Cathode materials
Nano-Al 203-coating
Electrochemical performa nee
The LiNi Mn O2 powder was coated with nano-Al 2O3 particles via ultrasonic coating,
trochemical performances were improved greatly. The X-ray diffraction, scanning electron
transmission electron microscope and energy dispersive
structure variati on, surface appeara nce
are successfully coated and the thickness cate that appropriate
amount
and coati ng status. of
of Al 2O3 coated
coati ng layer
is bene?cial
sca nning spectroscopy were employed to The results show that the nano-Al is about 20 - 25 nm. The XRD test to form a better layered structure
and its elecmicroscopy, research the
2O3 particles results in di- with smaller
cation disorder. The charge - discharge results show that LiNi Mn coated with AI2O3 of wt.% has initial discharge capacity of mA h ga1, initial coulombic ef?ciency of % at C over -
V and capacity retention of % much more than the pristine one of % after 30 cycles at
1 C. Especially, the rate capability of wt.% Al2°3-coated sample is improved evidentl