Mathematical formulation is being developed for the design/performance analysis of the lithium-ion cells currently being tested experimentally for high discharge rate applications. This paper presents the developed formulation to predict the reversible electric potentials of the cell anode and cathode insertion electrodes and the total cell reversible electric potential. The formulation also includes the electrochemical kinetics rate laws needed for the performance evaluation of a lithium-ion cell and the overall cell thermal energy balance to predict the cell average temperature as a function of time.