Das, ManoharJarid, SaadToulabi, MohammadWang, XiaWang, ZheEl-Syed, Mohammed A2026-09-282026-09-282026-01-01https://hdl.handle.net/10323/22202This dissertation investigates enhancements to battery charging techniques by addressing issues associated with Lithium-ion batteries, particularly those related to fast and safe charging. The research covers a series of interconnected topics that contribute to advancements in battery technology. One goal of this study is to improve the accuracy of battery modeling and parameter estimation, the other being development of new charging techniques, ultimately improving the reliability and longevity of Li-ion batteries.One of the primary objectives focuses on investigating the estimation of time-varying parameters of the Electrical-Equivalent Circuit (EEC) model, which is essential for accurate modeling of battery’s charging behavior. Two techniques were used for estimation: a direct continuous-time system identification technique based on State Variable Filtering (SVF) and the Indirect Discrete Time (IDT) technique. The results from both methods are compared to determine the most effective approach for accurate modeling. The second objective focuses on assessing the robustness of the parameter estimation techniques by integrating a dynamic, time-varying EEC model to enhance the accuracy of State-of-Charge estimation. Kalman filter in its various forms is utilized for SOC estimation. The third objective of this research is to create an improved Multi-stage Charging Current (MCC) profile. The goal is to optimize the charging current at each stage to reduce the total charge time while ensuring the safety of the battery by carefully monitoring its temperature during charging. To ensure efficient and effective charging of this technique without compromising the battery health, careful control of the charging current at each stage is required. The fourth objective of this study is to develop a continuous, exponentially decaying charging current profile. This technique addresses one of the shortcomings of MCC, by minimizing the stress fluctuations caused by abrupt shifts in current during transitions between stages. This optimized current profile offers a balance between fast charging and protecting the battery from potential damage.Text