Battery Time-Series Data Augmentation Using a GAF-Based Generative Framework Opy Das, Xin Sui, Filippo Sanfilippo, Souman Rudra Proceedings Eurocon 2025 21st International Conference on Smart Technologies, 2025 Generative models have gained significant attention in computer vision and natural language processing for their ability to generate realistic samples from complex data distributions. Inspired by these advancements and the persistent challenge of data scarcity in time-series domains, this work proposes a pioneering framework that transforms time-series data (e.g., voltage, current, temperature of lithium-ion batteries) into Gramian Angular Field (GAF) images for synthetic data generation using deep convolutional generative adversarial network (DCGAN) architecture. The proposed GAF-based GAN framework, validated on the Massachusetts Institute of Technology (MIT) battery dataset, generates samples that closely resemble real data and enables accurate signal reconstruction through inverse GAF transformation, effectively overcoming scale invariance and invertibility issues. To further demonstrate the quality of the synthetic signals, state of charge estimation (SOC) is performed using both original and augmented datasets. The results present that using augmented datasets help the models perform better than when trained only on the original data, highlighting the effectiveness of the proposed method for improving time-series data augmentation and state estimation.
Sensorless Temperature Monitoring of Lithium-Ion Batteries by Integrating Physics With Machine Learning Yusheng Zheng, Yunhong Che, Xiaosong Hu, Xin Sui, Remus Teodorescu IEEE Transactions on Transportation Electrification, 2024 The large-scale application of lithium-ion batteries in electric vehicles requires meticulous battery management to guarantee vehicular safety and performance. Temperatures play a significant role in the safety, performance, and lifetime of lithium-ion batteries. Therefore, the state of temperature (SOT) of batteries should be monitored timely by the battery management system. Due to limited onboard temperature sensors in electric vehicles, the SOT of most batteries must be estimated through other measured signals such as current and voltage. To this end, this paper develops an accurate method to estimate the surface temperature of batteries by combing the physics-based thermal model with machine learning. A lumped-mass thermal model is applied to provide prior knowledge of battery temperatures for machine learning. Temperature-related feature, such as internal resistance, is extracted in real-time and fed into the machine learning framework as supplementary inputs to enhance the accuracy of the estimation. A machine learning model, which combines a convolutional neural network with a long short-term memory neural network, is sequentially integrated with the thermal model to learn the mismatch between the model outputs and the real temperature values. The proposed method has been verified against experimental results, with accuracy improvement of 79.37% and 86.24% compared to conventional pure thermal model-based and pure data-driven approaches respectively.
Small-Sample-Learning-Based Lithium-Ion Batteries Health Assessment: An Optimized Ensemble Framework Xin Sui, Shan He, Remus Teodorescu IEEE Transactions on Industry Applications, 2024 Machine Learning is widely studied in battery state of health (SOH) estimation due to its advantage in establishing the non-linear mapping between measurements and SOH. However, the requirement of a big dataset and the lack of robustness limit the practical application, especially in small sample learning. To tackle these challenges, an optimal ensemble framework called BaggELM (bagging extreme learning machine) is proposed for battery SOH estimation. Specifically, the required dataset is reduced by optimizing the input voltage and the hyperparameters of the BaggELM algorithm. Moreover, a statistical post-processing method is used to aggregate multiple ELMs, and the final estimate is determined by the maximum probability density value. As a result, the effects of random parameterization of ELM and the training data size on SOH estimation are suppressed, thus improving the robustness and accuracy of the conventional BaggELM. Compared to other classic machine learning methods, the proposed method reduces the required data size, maintains strong robustness and high estimation accuracy, making it a promising solution for small-sample-based SOH estimation. Finally, the effectiveness of the proposed estimation framework is verified using the accelerated aging dataset from Lithium Iron Phosphate (LFP) and Nickel Manganese Cobalt (NMC) batteries.
Combing physics-based thermal model and machine learning for battery temperature estimation: The impact of model accuracy Yusheng Zheng, Yunhong Che, Xin Sui, Remus Teodorescu 2024 IEEE 10th International Power Electronics and Motion Control Conference Ipemc 2024 Ecce Asia, 2024 Temperature significantly impacts the safety, performance, and degradation of lithium-ion batteries (LIBs), and therefore should be monitored properly by the battery management system (BMS). Hybrid estimation methods by combining physics-based thermal models and machine learning (ML) algorithms, become very promising for sensorless temperature estimation given the limited number of onboard temperature sensors. In this hybrid estimation framework, the physics-based thermal model provides prior knowledge for the ML algorithm to help achieve an accurate final estimation. Therefore, the impact of model accuracy on the overall estimation performance needs to be investigated comprehensively. To this end, this paper investigated the performance of the hybrid estimation framework under different model accuracies, which stem from parameter uncertainties and unmodeled dynamics. Results suggest that the hybrid estimation model can still achieve high accuracy even though trained with inaccurate prior knowledge, demonstrating its robustness to different uncertainties.
Online Sensorless Temperature Estimation of Lithium-Ion Batteries Through Electro-Thermal Coupling Yusheng Zheng, Yunhong Che, Xiaosong Hu, Xin Sui, Remus Teodorescu IEEE ASME Transactions on Mechatronics, 2024 Owing to the nonnegligible impacts of temperature on the safety, performance, and lifespan of lithium-ion batteries, it is essential to regulate battery temperature to an optimal range. Temperature monitoring plays a fundamental role in battery thermal management, yet it is still challenged by limited onboard temperature sensors, particularly in large-scale battery applications. As such, developing sensorless temperature estimation is of paramount importance to acquiring the temperature information of each cell in a battery system. This article proposes an estimation approach to obtain the cell temperature by taking advantage of the electrothermal coupling effect of batteries. An electrothermal coupled model, which captures the interactions between the electrical and the thermal dynamics, is established, parameterized, and experimentally validated. A closed-loop observer is then designed based on this coupled model and the extended Kalman filter to estimate the battery temperature by merely using the voltage measurement as feedback. The electrothermal coupling effect enables the full observability of batteries’ internal states from their voltage, and contributes to an accurate and robust temperature estimation. The capability of the proposed estimation method has been demonstrated via experiments, with root-mean-square error less than 0.7 °C in various scenarios.
AI for Smart Battery State Estimation: A Perspective X. Sui, Y. Che, Y. Zheng, N. André Weinreich, S. He, R. Teodorescu 2024 IEEE 10th International Power Electronics and Motion Control Conference Ipemc 2024 Ecce Asia, 2024 In battery management systems (BMSs), state estimation stands as a pivotal element yet encounters significant challenges. These include the poor observability inherent in fixed configuration battery packs, limited generalizability of pre-trained machine learning models, and the deficiency of higher-level management strategies. To address these obstacles, we propose a forward-looking perspective on the future BMS state estimation, introducing the concept of a "Smart Battery". Battery digital twin enables synthetic data generation and physics-informed AI development. This approach integrates battery digital twin to generate synthetic data, which is then used for data augmentation and physics-informed AI development. Additionally, it incorporates advanced data cleaning and selection techniques to preserve essential information and augment data management efficiency. Leveraging cutting-edge AI algorithms, such as transfer learning and meta-learning, aims to mitigate issues of model generalization and feature invalidation under various operating conditions. Furthermore, this paper emphasizes the importance of multi-task learning for batteries, enabling comprehensive health assessments. By fully utilizing both short-term estimations and long-term predictions, the proposed framework contributes to the advancement of higher-level health and thermal management designs. We aim to furnish pioneering insights for state estimation in future intelligent BMSs.
Predictive health assessment for lithium-ion batteries with probabilistic degradation prediction and accelerating aging detection Yunhong Che, Yusheng Zheng, Florent Evariste Forest, Xin Sui, Xiaosong Hu, Remus Teodorescu Reliability Engineering and System Safety, 2024 Predictive health assessment is of vital importance for smarter battery management to ensure optimal and safe operations and thus make the most use of battery life. This paper proposes a general framework for battery aging prognostics in order to provide the predictions of battery knee, lifetime, state of health degradation, and aging rate variations, as well as the assessment of battery health. Early information is used to predict knee slope and other life-related information via deep multi-task learning, where the convolutional-long-short-term memory-bayesian neural network is proposed. The structure is also used for online state of health and degradation rate predictions for the detection of accelerating aging. The two probabilistic predicted boundaries identify the accelerating aging regions for battery health assessment. To avoid wrong and premature alarms, the empirical model is used for data preprocessing and the slope is predicted together with the state of health via multi-task learning. A cloud-edge framework is considered where fine-tuning is adopted for performance improvement during cycling. The proposed general framework is flexible for adjustment to different practical requirements and can be extrapolated to other batteries aged under different conditions. The results indicate that the early predictions are improved using the proposed method compared to multiple single feature-based benchmarks, and that integration of the algorithm is improved. The sequence prediction is reliable for different predicted lengths with root mean square errors of less than 1.41%, and the detection of accelerating aging can guide reliable predictive health management.
Thermal state monitoring of lithium-ion batteries: Progress, challenges, and opportunities Yusheng Zheng, Yunhong Che, Xiaosong Hu, Xin Sui, Daniel-Ioan Stroe, Remus Teodorescu Progress in Energy and Combustion Science, 2024 Transportation electrification is a promising solution to meet the ever-rising energy demand and realize sustainable development. Lithium-ion batteries, being the most predominant energy storage devices, directly affect the safety, comfort, driving range, and reliability of many electric mobilities. Nevertheless, thermal-related issues of batteries such as potential thermal runaway, performance degradation at low temperatures, and accelerated aging still hinder the wider adoption of electric mobilities. To ensure safe, efficient, and reliable operations of lithium-ion batteries, monitoring their thermal states is critical to safety protection, performance optimization, as well as prognostics, and health management. Given insufficient onboard temperature sensors and their inability to measure battery internal temperature, accurate and timely temperature estimation is of particular importance to thermal state monitoring. Toward this end, this paper provides a comprehensive review of temperature estimation techniques in battery systems regarding their mechanism, framework, and representative studies. The potential metrics used to characterize battery thermal states are discussed in detail at first considering the spatiotemporal attributes of battery temperature, and the strengths and weaknesses of applying such metrics in battery management are also analyzed. Afterward, various temperature estimation methods, including impedance/resistance-based, thermal model-based, and data-driven estimations, are elucidated, analyzed, and compared in terms of their strengths, limitations, and potential improvements. Finally, the key challenges to battery thermal state monitoring in real applications are identified, and future opportunities for removing these barriers are presented and discussed.
Li-ion Battery Digital Twin Based on Online Impedance Estimation Abhijit Kulkarni, Hoda Sorouri, Yusheng Zheng, Xin Sui, Arman Oshnoei, Nicolai André Weinreich, Remus Teodorescu Cpe Powereng 2023 17th IEEE International Conference on Compatibility Power Electronics and Power Engineering, 2023
Identification of Lithium-Ion Battery Degradation Mechanisms During Pulsed Current Charging Through Non-invasive and Post-Mortem Analysis S Jin, J Guo, X Sui, X Huang, S Wang, X He, DI Stroe Automotive Innovation, 1-14 , 2026 2026 Citations: 1
Artificial Intelligence-Based State-of-Health Estimation of Lithium-Ion Batteries X Sui MDPI-Multidisciplinary Digital Publishing Institute , 2025 2025
Thermodynamic modelling of cross-shaped microstructured surfaces for superhydrophobicity applications Y Xue, Y Wang, B Yuan, X Sui, W Liang Physics of Fluids 37 (11) , 2025 2025 Citations: 1
Multi-response controllable microstructured superhydrophobic surfaces for full-process dynamic anti-icing and de-icing Y Wang, Y Xue, Y Wang, B Yuan, Y Zheng, W Liang, Y Sun, X Sui Composites Science and Technology 267, 111183 , 2025 2025 Citations: 33
Battery Time-Series Data Augmentation Using a GAF-Based Generative Framework O Das, X Sui, F Sanfilippo, S Rudra IEEE EUROCON 2025-21st International Conference on Smart Technologies, 1-6 , 2025 2025
A Virtual Platform for Modular Smart Battery Testing and Prototyping F Simonetti, R Di Fonso, N Weinreich, Y Zheng, A Oshnoei, X Sui, ... The 26th European Conference on Power Electronics and Applications , 2025 2025
TRACKSIM: A multi-level simulation framework for near-life battery data generation NA Weinreich, X Sui, R Teodorescu, KG Larsen The 26th European Conference on Power Electronics and Applications , 2025 2025 Citations: 2
Real-time sensorless temperature estimation of lithium-ion batteries based on online operando impedance acquisition Y Zheng, Y Che, J Guo, NA Weinreich, A Kulkarni, A Nadeem, X Sui, ... IEEE Transactions on Power Electronics 39 (10), 13853-13868 , 2024 2024 Citations: 32
Combing physics-based thermal model and machine learning for battery temperature estimation: The impact of model accuracy Y Zheng, Y Che, X Sui, R Teodorescu 2024 IEEE 10th International Power Electronics and Motion Control Conference … , 2024 2024
AI for smart battery state estimation: A perspective X Sui, Y Che, Y Zheng, NA Weinreich, S He, R Teodorescu 2024 IEEE 10th International Power Electronics and Motion Control Conference … , 2024 2024 Citations: 3
Online sensorless temperature estimation of lithium-ion batteries through electro-thermal coupling Y Zheng, Y Che, X Hu, X Sui, R Teodorescu IEEE/ASME Transactions on Mechatronics 29 (6), 4156-4167 , 2024 2024 Citations: 19
Small-sample-learning-based lithium-ion batteries health assessment: An optimized ensemble framework X Sui, S He, R Teodorescu IEEE Transactions on Industry Applications 60 (3), 4366-4380 , 2024 2024 Citations: 23
Battery state-of-health estimation using machine learning DI Stroe, X Sui Control of Power Electronic Converters and Systems, 383-430 , 2024 2024 Citations: 1
Thermal state monitoring of lithium-ion batteries: Progress, challenges, and opportunities Y Zheng, Y Che, X Hu, X Sui, DI Stroe, R Teodorescu Progress in Energy and Combustion Science 100, 101120 , 2024 2024 Citations: 288
Predictive health assessment for lithium-ion batteries with probabilistic degradation prediction and accelerating aging detection Y Che, Y Zheng, FE Forest, X Sui, X Hu, R Teodorescu Reliability Engineering & System Safety 241, 109603 , 2024 2024 Citations: 88
Sensorless temperature estimation for lithium-ion batteries via online impedance acquisition Y Zheng, NA Weinreich, A Kulkarni, X Sui, R Teodorescu IET Conference Proceedings CP858 2023 (28), 53-57 , 2023 2023 Citations: 2
Hardware design of high current prismatic smart battery packs A Kulkarni, R Teodorescu, X Sui, A Oshnoei Energy Storage Conference 2023 (ESC 2023) 2023, 41-45 , 2023 2023 Citations: 2
Early Prediction of Lithium-Ion Batteries Lifetime via Few-Shot Learning X Sui, S He, Y Zheng, Y Che, R Teodorescu IECON 2023-49th Annual Conference of the IEEE Industrial Electronics Society , 2023 2023 Citations: 7
Ultrafast Feature Extraction for Lithium-Ion Battery Health Assessment X Sui, S He, R Teodorescu 2023 25th European Conference on Power Electronics and Applications (EPE'23 … , 2023 2023
Sensorless State of Temperature Estimation for Smart Battery based on Electrochemical Impedance Y Zheng, NA Weinreich, A Kulkarni, Y Che, H Sorouri, X Sui, ... 2023 25th European Conference on Power Electronics and Applications (EPE'23 … , 2023 2023 Citations: 12
MOST CITED SCHOLAR PUBLICATIONS
A review of non-probabilistic machine learning-based state of health estimation techniques for Lithium-ion battery X Sui, S He, SB Vilsen, J Meng, R Teodorescu, DI Stroe Applied Energy 300, 117346 , 2021 2021 Citations: 441
Thermal state monitoring of lithium-ion batteries: Progress, challenges, and opportunities Y Zheng, Y Che, X Hu, X Sui, DI Stroe, R Teodorescu Progress in Energy and Combustion Science 100, 101120 , 2024 2024 Citations: 288
On the feature selection for battery state of health estimation based on charging–discharging profiles Y Li, DI Stroe, Y Cheng, H Sheng, X Sui, R Teodorescu Journal of Energy Storage 33, 102122 , 2021 2021 Citations: 190
A review of pulsed current technique for lithium-ion batteries X Huang, Y Li, AB Acharya, X Sui, J Meng, R Teodorescu, DI Stroe Energies 13 (10), 2458 , 2020 2020 Citations: 131
Lithium-ion battery state-of-health estimation in electric vehicle using optimized partial charging voltage profiles J Meng, L Cai, DI Stroe, G Luo, X Sui, R Teodorescu Energy 185, 1054-1062 , 2019 2019 Citations: 112
Data efficient health prognostic for batteries based on sequential information-driven probabilistic neural network Y Che, Y Zheng, Y Wu, X Sui, P Bharadwaj, DI Stroe, Y Yang, X Hu, ... Applied Energy 323, 119663 , 2022 2022 Citations: 109
Overview of machine learning methods for lithium-ion battery remaining useful lifetime prediction S Jin, X Sui, X Huang, S Wang, R Teodorescu, DI Stroe Electronics 10 (24), 3126 , 2021 2021 Citations: 102
A review of lithium-ion battery capacity estimation methods for onboard battery management systems: Recent progress and perspectives J Peng, J Meng, D Chen, H Liu, S Hao, X Sui, X Du Batteries 8 (11), 229 , 2022 2022 Citations: 93
Predictive health assessment for lithium-ion batteries with probabilistic degradation prediction and accelerating aging detection Y Che, Y Zheng, FE Forest, X Sui, X Hu, R Teodorescu Reliability Engineering & System Safety 241, 109603 , 2024 2024 Citations: 88
The Degradation Behavior of LiFePO4/C Batteries during Long-Term Calendar Aging X Sui, M Świerczyński, R Teodorescu, DI Stroe Energies 14 (6), 1732 , 2021 2021 Citations: 82
Boosting battery state of health estimation based on self-supervised learning Y Che, Y Zheng, X Sui, R Teodorescu Journal of Energy Chemistry 84, 335-346 , 2023 2023 Citations: 70
Unravelling and quantifying the aging processes of commercial Li (Ni 0.5 Co 0.2 Mn 0.3) O 2/graphite lithium-ion batteries under constant current cycling J Guo, S Jin, X Sui, X Huang, Y Xu, Y Li, PK Kristensen, D Wang, ... Journal of Materials Chemistry A 11 (1), 41-52 , 2023 2023 Citations: 69
Smart battery technology for lifetime improvement R Teodorescu, X Sui, SB Vilsen, P Bharadwaj, A Kulkarni, DI Stroe Batteries 8 (10), 169 , 2022 2022 Citations: 61
Fuzzy entropy-based state of health estimation for Li-ion batteries X Sui, S He, J Meng, R Teodorescu, DI Stroe IEEE Journal of Emerging and Selected Topics in Power Electronics 9 (4 … , 2020 2020 Citations: 58
Battery health prognostic with sensor-free differential temperature voltammetry reconstruction and capacity estimation based on multi-domain adaptation Y Che, SB Vilsen, J Meng, X Sui, R Teodorescu Etransportation 17, 100245 , 2023 2023 Citations: 53
Sensorless temperature monitoring of lithium-ion batteries by integrating physics with machine learning Y Zheng, Y Che, X Hu, X Sui, R Teodorescu IEEE Transactions on Transportation Electrification 10 (2), 2643-2652 , 2023 2023 Citations: 52
Wireless smart battery management system for electric vehicles X Huang, AB Acharya, J Meng, X Sui, DI Stroe, R Teodorescu 2020 IEEE Energy Conversion Congress and Exposition (ECCE), 5620-5625 , 2020 2020 Citations: 52
A review of management architectures and balancing strategies in smart batteries X Huang, X Sui, DI Stroe, R Teodorescu IECON 2019-45th Annual Conference of the IEEE Industrial Electronics Society … , 2019 2019 Citations: 35
Multi-response controllable microstructured superhydrophobic surfaces for full-process dynamic anti-icing and de-icing Y Wang, Y Xue, Y Wang, B Yuan, Y Zheng, W Liang, Y Sun, X Sui Composites Science and Technology 267, 111183 , 2025 2025 Citations: 33
Real-time sensorless temperature estimation of lithium-ion batteries based on online operando impedance acquisition Y Zheng, Y Che, J Guo, NA Weinreich, A Kulkarni, A Nadeem, X Sui, ... IEEE Transactions on Power Electronics 39 (10), 13853-13868 , 2024 2024 Citations: 32