This study presents a detailed modeling approach to simulate heat generation in lithium-ion batteries using LFP and Graphite electrodes. LFP, known for its high thermal stability, long cycle life, and inherent safety, serves as a widely used cathode material in energy storage applications. Graphite, the standard anode material, offers high electrical conductivity, energy density, and stable cycling performance. Together, these materials define the thermal characteristics of modern lithium-ion cells and play a crucial role in determining battery efficiency and thermal behavior.
A detailed understanding of heat generation at the material, component, and mechanism levels is essential for improving battery performance. Heat generation originates from multiple sources, including Joule heating—divided into ohmic and polarization heat contributions—as well as entropy changes within the electrodes. The model provides a quantitative analysis of thermal contributions from individual cell components, including the cathode, anode, and separator/electrolyte. This level of analysis helps clarify how heat accumulates within the cell, how different components contribute to thermal losses, and how these losses evolve over the course of cycling. Such insights are critical for designing more thermally stable and efficient battery systems.
The accuracy of the model is evaluated by comparing the simulated voltage curves with experimental voltage measurements obtained from custom-built cells under controlled cycling conditions. This comparison ensures that the model can reliably capture the key electrochemical and thermal characteristics of real battery systems. A key outcome of this approach is the identification of dominant heat generation mechanisms and their variations under different operating conditions. The ability to link heat generation to fundamental electrochemical processes provides a foundation for improving the efficiency, safety, and longevity of lithium-ion batteries while also informing the development of optimized thermal management strategies.