Deep Hybrid Temporal Modeling with TCN-GRU-Transformer for Lithium-Polymer Battery State-of-Charge Estimation
Omar LAMMAMRI, Brahim ZRAIBI, Mohamed MANSOURI, Abdelghani EZZAHI, Adam AFADISS
Abstract. Accurate state-of-charge (SOC) estimation is critical for safe and efficient battery operation in electric vehicles and stationary energy storage systems. This study proposes a hybrid deep learning model that combines a Temporal Convolutional Network (TCN) for local temporal feature extraction, a Gated Recurrent Unit (GRU) for sequential dynamics, and a Transformer block to capture longer-range dependencies in battery signals. The model is trained and validated using experimentally measured lithium-Polymer battery data and is benchmarked against standalone TCN, GRU, and Transformer baselines under the same data splits and evaluation protocol. On the test set, the proposed hybrid architecture achieves a mean absolute error (MAE) of 0.66%, a root mean square error (RMSE) of 0.88%, and a coefficient of determination (R²) of 0.9992, consistently outperforming the individual models. The results indicate that integrating complementary temporal modeling mechanisms improves estimation accuracy and robustness, supporting real-time SOC prediction in practical battery management systems.
Keywords
State of Charge, Lithium Polymer Battery, Deep Learning, TCN, GRU, Hybrid Model
Published online 4/25/2026, 7 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Omar LAMMAMRI, Brahim ZRAIBI, Mohamed MANSOURI, Abdelghani EZZAHI, Adam AFADISS, Deep Hybrid Temporal Modeling with TCN-GRU-Transformer for Lithium-Polymer Battery State-of-Charge Estimation, Materials Research Proceedings, Vol. 64, pp 164-170, 2026
DOI: https://doi.org/10.21741/9781644904091-20
The article was published as article 20 of the book Energy Futures
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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