Internal resistance reduction strategies for high-power and fast-charging Lithium-ion batteries

With the rapid development of electric vehicles and portable electronic devices, the demand for high-power and fast-charging Lithium-ion batteries has seen exponential growth. The internal resistance of Lithium-ion batteries, as a key physical parameter, limits both the efficiency of fast-charging and the performance of high-power energy storage systems, and development of efficient strategies to reduce internal resistance has become a key focus for recent research. This review systematically summarizes strategies for reducing the internal resistance of high-power Lithium-ion batteries. It begins by highlighting innovative advancements of key components, including electrode materials design, optimization of electrolyte, regulation of separator properties, improvements in current collector structures and the refinement of tab connection processes. In addition, the review discusses how advanced manufacturing techniques affecting internal resistance, such as thick-electrode engineering, multi-level cell series connection, and the selection and optimization of battery shapes. Furthermore, system-controlling optimization and how internal resistance varies, covering innovative charging protocol design, the application of artificial intelligence and machine learning models and the implementation of improved thermal management systems are addressed. Finally, challenges and future directions in regulating internal resistance for developing high-power and fast-charging Lithium-ion batteries are highlighted. The review is particularly pertinent for electric vehicles, autonomous unmanned aerial vehicles, high-power military equipment, and large-scale energy storage stations, thereby paving the way for advancements in energy storage technology.