Morphology controlled Si-modified LiNi0.5Mn1.5O4 microspheres as high performance high voltage cathode materials in lithium ion batteries

作者：Nageswaran Shubha; Keppeler Miriam; Kim Sung Jin; Srinivasan Madhavi

来源：Journal of Power Sources, 2017, 346: 89-96.

DOI：10.1016/j.jpowsour.2017.02.013

• Lithium ion battery
• High-voltage spinel
• Lithium nickel manganese oxide
• Silicon doping
• Cycling stability
• Morphology control

Well-crystallized, microspherical LiNi0.5Mn1.5-nSinO4 (0.05 < n < 0.2) is successfully synthesized by a template directed approach in combination with the partial substitution of manganese by silicon. Structural and electrochemical characteristics are investigated through FE-SEM, XRD, EDX, cyclic voltammetry and galvanostatic charge/discharge testing. Spherical shape and incorporation of silicon into the crystal leads to higher proportion of the disordered Fd-3m phase, and electrochemical performance is significantly improved. High capacity retention of 99.4% after 100 cycles at 1 C rate for LiNi0.5Mn1.45Si0.05O4 microspheres is achieved, which is superior compared to 93.1% capacity retention of the pristine LiNi0.5Mn1.5O4 microspheres. Since the Si-O bond exhibits higher dissociation energy compared to the dissociation energies of the Mn-O or Ni-O bonds, the excellent electrochemical performance might be associated with an increased structural and chemical stability caused by incorporation of silicon into the oxygen rich crystal lattice.

• 出版日期2017-4-1