This study proposed a detailed 1D electrochemical model for the simulation of Li-S battery involving the conservation of mass, energy. This electrochemical model can be further utilized to simulate a Li-S full cell. We found that, typically, as the higher the charging rates, the relative higher the temperature within the Li-S battery. For example, this model can be extended to 2D or 3D model to simulate Li-S pouch cells. In the future, a more detailed 3D model will be developed to consider the different properties of various components within sulfur cathode materials, for example, various effects of increasing charging rates on temperature distribution, stress distribution within the Li-S battery will be further probed. We believe this electrochemical model will help battery designers improve Li-S batteries' design and safety.