Lithium-ion (Li-ion) batteries have become the most common rechargeable batteries for consumer electronics and automotive applications due to their high-energy densities, decent power density, relatively high cell voltages, and low weight-to-volume ratios.
The term Li-ion battery refers to an entire family of battery chemistries. The common properties of these chemistries are that the negative and the positive electrode materials serve as hosts for lithium ions and that the battery contains a nonaqueous electrolyte.
The increased demand and the pressure for improving battery performance have intensified the need for mathematical modeling. Modeling and simulations allow for the analysis of an almost unlimited number of design parameters and operating conditions at a relatively small cost. Experimental tests are used to provide the necessary validation of the models.
The Newman Model
Mathematical models can describe and predict cell voltage and current density during discharge, recharge, transient studies, as well as include mechanisms for aging and failure. The influence of different material properties and design parameters can be studied under these conditions.
The workhorse for high-fidelity modeling of Li-ion batteries is the so-called Newman model. This model has been validated by many scientists over the years. It has also been further developed and extended by others, for example, to account for designs with multiple electrode materials, the formation of a solid electrolyte interface, and alternative electrode kinetics. The original 1D model has later also been formulated by COMSOL for 2D, 2D axisymmetric, and 3D models.