ACTIVE EQUALIZATION CIRCUIT ANALYSIS.pptx

Different equalization topologies in battery equalization of lithium ion

1. ACTIVE EQUALIZATION CIRCUIT TOPOLOGY OF LITHIUM-ION BATTERY PACK: A REVIEW Presented At Hybrid International Conference of the Department of Mechatronic Engineering, University of Nigeria, Nsukka.  

2. Introduction The global energy crisis has increased the focus on sustainable energy solutions. Lithium-ion batteries (LIBs) are crucial in electric vehicles (EVs) and energy storage systems. Their advantages include high energy density, low cost, and rechargeability. Inconsistencies in the internal and exterior environments of lithium-ion cells once they are connected as a battery pack can significantly limit the pack's capacity

3. Cell Balancing

4. Overview of Active Equalization Circuits Various active equalization methods: Cell-to-Cell Energy Transfer Cell-to-Pack Energy Transfer Pack-to-Cell Energy Transfer Uses DC/DC converters and selection switches.

5. Cell-to-cell energy flow technique Uses a DC/DC converter with an array of selection switches. Advantage: Faster balancing speed compared to other methods. Challenge: Requires many switching elements, leading to low equalizing efficiency. Optimization efforts focus on improving efficiency and reducing complexity.

6. Cell to pack energy flow technique Uses a single DC/DC converter to transfer energy from an overcharged cell to the entire battery pack. Advantage: High equalization speed due to significant voltage difference. Challenge: Low balancing efficiency caused by transformer losses. Research focuses on improving efficiency while maintaining high speed.

7. Pack to cell energy flow technique Transfers charge from the battery pack to an undercharged cell. The DC/DC converter connects the pack to the identified cell. Similar to the cell-to-pack technique, but in reverse direction. Focus on optimizing efficiency and minimizing energy losses.

8. Conclusion Battery equalization is vital for LIB efficiency and longevity. Active equalization offers superior performance over passive methods. Ongoing research aims to optimize equalization topologies for improved energy management.