In order to ensure the safe use of the new cobalt-free lithium battery, an electrochemical-thermal coupling model was established for the cobalt-free lithium battery to study its charge-discharge characteristics and its electrical and thermal characteristics at different rates and different ambient temperatures. It is found that the charge-discharge characteristics of cobalt-free lithium batteries meet the characteristics of typical ternary lithium batteries, and the high charge-discharge rate and low temperature environment increase the temperature inhomogeneity of the battery and reduce the thermal stability of the battery. Under high-rate charge and discharge, ohmic heat accounts for a large proportion, and the battery produces more heat; in the low temperature environment, the polarization effect of the battery is intensified, and the voltage drop is increased. This study has important reference value for evaluating the electrothermal characteristics of cobalt-free lithium batteries and the safe use of batteries.