Excellent Electrochemical Performance and Thermal Stability of LiNi0.5Mn1.5O4 Thin-film Cathode Prepared by Pulsed Laser Deposition

Lithium secondary batteries using LiNi0.5Mn1.5O4 (LNMO) films as a cathode material were prepared by pulsed laser deposition on stainless steel substrates. X-ray diffraction and Field-emission Scanning Electron Microscope results show that the film deposited at 750 degrees C exhibits good crystallinity with well-defined grains structure. Galvanostatic charge/discharge measurement results revealed that the reversible capacity maintains 116.8mAhg(-1) after 100 cycles at 0.5C. It also exhibits excellent rate capability, as the rates increase to 5 and 10 C, about 95.4% and 92.3% of its initial capacity at 0.2C can be retained. In additional, thermal stability of the Al2O3 coated LNMO thin film cathodes were also explored. The high temperature cyclic performance of LNMO thin film electrode was significantly enhanced by the coating.