Abstract:

This study integrates the electrochemical thermal coupling model with the reverse disassembly method to facilitate easier access for end-users to electrochemical parameter data about the battery cell's interior. It employs finite element simulation analysis and electrochemical parameter optimization experiments to validate the accuracy of the obtained parameters. Furthermore, it examines the impact of the Bruggman coefficient, reaction rate constant, and solid-phase diffusion coefficient on the charging and discharging performance and the temperature of power batteries. The findings reveal that the reverse disassembly method effectively captures the dynamic and thermodynamic battery parameters, with an error margin of approximately 3% for voltage and temperature in standard lithium batteries. Notably, the Bruggeman coefficient influences voltage, particularly in the middle and later stages of discharge, wherein an increase in its value amplifies polarization. Moreover, as the Bruggeman coefficient rises, battery temperature demonstrates a decreasing trend. The reaction rate constant affects voltage across the entire discharge range, inversely correlating with temperature; higher reaction rate constants correspond to reduced polarization. Similarly, the solid-phase diffusion coefficient influences voltage within the low state-of-charge (SOC) range, with higher values diminishing polarization.

Key words: electrochemical thermal coupling model, reverse disassembly, accuracy verification, parameter identification