摘要
This study represents the electrochemical performance and lithium transportation behaviors of spinel LiNi 0.5 Mn 1.5 O 4 cathode operated in a wide range of temperatures from -20 to 60°C. The correlative lithium diffusion coefficients are derived via electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques, respectively. Based on the modeling of EIS, the lithium diffusivity of LiNi 0.5 Mn 1.5 O 4 is estimated in the range of 10 -11 around 25°C. The specific capacity of LiNi 0.5 Mn 1.5 O 4 cathode is highly associated with the change of Li-ion mobility, which reveals a distinctive trend with applied temperatures. A strong correlation is also found between the apparent activation energy and lithium diffusivity. The change of activation energy is a key factor in dominating the kinetic reaction of Li/LiNi 0.5 Mn 1.5 O 4 cells. Furthermore, the voltage polarization recorded from CV profile also perfectly follows the lithium transportation scenario. This study elaborates a profound discussion for temperature effects on electrochemical properties of LiNi 0.5 Mn 1.5 O 4 cathode material.