tailieunhanh - Enhancement of Li–ion battery capacity using nickel doped LiFePO4 as cathode material

The structure and morphology of synthesized materials were examined by X–ray diffraction, Scanning electronic microscopy and Raman vibrational micro–spectroscopy. The electrochemical performances of doped materials were studied in Swagelok–type cell using LiPF6/EC–DMC (1:1) as electrolyte. LiFe1–xNixPO4 was shown to exhibit homogenous particles size of 50 ÷ 150 nm. The doped materials were titrated to quantify iron and nickel contents in samples. As anticipated, the electrochemical performances of LiFe1–xNixPO4were significantly enhanced compared to those of undoped LiFePO4. | Journal of Science and Technology 55 (1B) (2017) 276–283 ENHANCEMENT OF Li–ION BATTERY CAPACITY USING NICKEL DOPED LiFePO4 AS CATHODE MATERIAL La Thi Hang1, 2, 3, *, Le My Loan Phung4, Nguyen Thi My Anh5, Hoang Xuan Tung5, Doan Phuc Luan5, Nguyen Nhi Tru5 1 Vinh Long University of Technology Education (VLUTE) 73 Nguyen Hue Street, Vinh Long City, Vinh Long Province, Vietnam 2 Institute of Applied Materials Science – VAST 1 Mac Dinh Chi Street, Ben Nghe Ward,, District 1, Ho Chi Minh City, Vietnam 3 Graduate University of Science & Technology – VAST 18 Hoang Quoc Viet Street, Nghia Do Ward, Cau Giay District, Hanoi, Vietnam 4 Applied Physical Chemistry Lab, University of Science – VNU HCM 227 Nguyen Van Cu Street, Ward 4, District 5, Ho Chi Minh City, Vietnam 5 Faculty of Materials Technology, University of Technology – VNU HCM 268 Ly Thuong Kiet Street, Ward 14, District 10, Ho Chi Minh City, Vietnam * Email: hanglt@ Received: 30 December 2016; Accepted for Publication: ABSTRACT Selective supervalent cations (M = Ni, Mn, La etc.) doped LiFePO4 (LFP) is an effective route to enhance its electrical conductivity, thereby improving electrochemical performances of lithium–ion batteries. For this purpose, nickel doped LiFePO4 based cathode material was investigated at different substitution amounts (xNi = , ). LiFe1–xNixPO4 (LFNP) was synthesized from Ni(NO3), , , H3PO4, and ascorbic acid precursors via solvothermal technique, followed by calcination in nitrogen atmosphere at 550 °C for 5 h. The structure and morphology of synthesized materials were examined by X–ray diffraction, Scanning electronic microscopy and Raman vibrational micro–spectroscopy. The electrochemical performances of doped materials were studied in Swagelok–type cell using LiPF6/EC–DMC (1:1) as electrolyte. LiFe1–xNixPO4 was shown to exhibit homogenous particles size of 50 ÷ 150 nm. The doped materials were titrated to quantify iron and nickel contents