## 4 SOC Estimation Method
### EKF Method
The proposed method did not consider the aging of the battery, and the calculations were carried out using the MATLAB software on a computer. Further works include: (1) Verification and application of the MM-MA method and the fuzzy SOC estimation algorithm in actual BMS; (2) building a new battery model that considers battery aging; (3) verification of the effectiveness of the proposed method under other working conditions. All authors contributed to the paper. Conceptualization, X.L. and Y.Z. ; data curation, D.Q. ; investigation, X.L. and L.Z. ; methodology, X.L. ; project administration, X.L. and Y.Z. ; software, X.L. ; validation, X.L. and L.Z. ; writing--original draft, X.L. and D.Q. ; writing--review and editing, X.L. and Y.Z. This research was funded by the National Natural Science Foundation of China, grant number 51505290. The authors declare no conflict of interest. ## References

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\begin{tabular}{c c} \hline \hline
**SOC Estimation Algorithm** & **Time (s)** \\ \hline AH & 0.0479 \\ EKF & 65.8570 \\ Fuzzy fusion & 65.8793 \\ \hline \hline \end{tabular}
\end{table} 
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