Lithium ion (Li-ion) batteries, consisting of multiple electrochemical cells, are complex system whose high electrochemical and thermal stability is often critical to the well-being and functional capabilities of the electric device. Considering any change in the specifications may significantly affect the overall performance and life of a battery, an investigation of the impacts of the electrode thickness and initial electrolyte salt concentration on the electrochemical and thermal properties of lithium-ion cells based on experiments and a coupling model composed of a 1D electrochemical model and a 3D thermal model is conducted in this work. Pertinent results have demonstrated that the electrode thickness as well as the electrolyte salt concentration can significantly influence the battery from many key aspects such as the energy density, voltage, temperature, distribution and proportion of different heat sources and ability to prevent lithium plating.