Electro-thermal coupled modeling and balancing strategy of lithium-ion batteries based on digital twin

To address the inconsistency and complex coupling effects between electrochemical and thermal behaviors in lithium-ion batteries, this paper proposes a digital-twin-based electro-thermal coupling model and corresponding balancing strategies. First, a multiscale coupled model integrating equivalent circuit and thermal conduction mechanisms is established, enabling the dynamic interaction of current, voltage, and temperature under realistic working conditions. Then, based on the digital twin framework, an adaptive parameter updating mechanism is designed to ensure long-term model fidelity with real operation data. The results show that the SOC-based balancing strategy significantly improves consistency among cells and extends the overall lifespan of the battery pack, as evidenced by lower SOH variance and higher average SOH retention. This study provides theoretical and simulation support for developing intelligent battery management systems with self-adaptive balancing capabilities.