The development of a comprehensive battery simulator is essential for future improvements in the durability, performance and service life of lithium-ion batteries. Although simulations can never replace actual experimental data, they can still be used to provide valuable insights into the performance of the battery, especially under different operating conditions. In addition, a single-cell model can be easily extended to the pack level and can be used in the optimization of a battery pack. The first step in building a simulator is to create a model that can effectively capture both the voltage response and thermal behavior of the battery. However, generating a model can be time-consuming, often requiring running a large number of experiments. Therefore, the focus of this paper is to develop an electro-chemical battery model with a high degree of accuracy while minimizing the number of experiments that will be carried out. The entire battery model will be composed of four submodels: a heat generation model, a thermal model, a battery parameter model and a voltage response model. The paper will provide a brief description on each of these four sub-models and how they are correlated with each other. The obtained comprehensive model will then be validated by testing on a 20 Ah lithium iron phosphate battery. The results show that the electro-thermal model can adequately capture both the voltage and thermal trends in the battery. These findings are beneficial for battery design and optimization, since development of a model that can be produced with a limited number of experiments is essential for creating a battery simulator.