Decoding Battery Failure: A New Approach to Intelligent Diagnosis

Author: Denis Avetisyan


Researchers have developed a framework that combines physical insights with the power of artificial intelligence to pinpoint battery faults with unprecedented accuracy and clarity.

The BatteryAgent framework establishes a tiered architecture-encompassing physics-based perception, gradient-boosted detection with SHAP-driven attribution, and large language model reasoning-to diagnose battery faults and propose maintenance through a <span class="katex-eq" data-katex-display="false"> \text{Numeric-to-Semantic} </span> bridge, thereby translating data into actionable insights.
The BatteryAgent framework establishes a tiered architecture-encompassing physics-based perception, gradient-boosted detection with SHAP-driven attribution, and large language model reasoning-to diagnose battery faults and propose maintenance through a \text{Numeric-to-Semantic} bridge, thereby translating data into actionable insights.

The BatteryAgent framework synergizes physics-informed feature engineering, SHAP value interpretation, and large language models for advanced lithium-ion battery fault diagnosis in battery management systems.

While deep learning excels at detecting lithium-ion battery faults, its lack of interpretability hinders effective root cause analysis and proactive maintenance. This limitation motivates the development of ‘BatteryAgent: Synergizing Physics-Informed Interpretation with LLM Reasoning for Intelligent Battery Fault Diagnosis’, a novel framework integrating physics-based feature engineering with the reasoning capabilities of large language models. By bridging numerical data with semantic knowledge, BatteryAgent achieves highly accurate, interpretable multi-type fault diagnosis, surpassing state-of-the-art methods and shifting the paradigm from passive detection to intelligent assessment. Could this approach unlock a new era of predictive battery management and enhanced safety for electric vehicle and energy storage systems?


The Persistent Challenge of Accurate Battery State Determination

Battery health assessment historically pivots between two principal approaches, each presenting notable limitations. Physics-based models, striving for mechanistic accuracy, attempt to replicate the complex electrochemical processes within a battery; however, these models often demand substantial computational resources and struggle to encompass the nuances of real-world operating conditions and aging effects. Conversely, data-driven methodologies, leveraging statistical analysis and machine learning, offer scalability and adaptability, but frequently sacrifice interpretability, hindering a true understanding of the underlying fault mechanisms and potentially leading to unreliable diagnoses when confronted with unforeseen scenarios or data variations. This inherent trade-off between mechanistic insight and computational efficiency presents a persistent challenge in achieving accurate and robust battery fault diagnosis.

While offering valuable insight into the underlying processes within a battery, physics-based models face inherent limitations in practical application. Approaches like Electrochemical Models and Equivalent Circuit Models excel at providing an interpretable representation of battery behavior, detailing phenomena such as ion transport and electrochemical reactions. However, accurately translating these complex processes into a computationally feasible format proves challenging. The intricate nature of these models often demands significant processing power, hindering real-time fault diagnosis. Furthermore, simplifying assumptions required to manage computational load can lead to discrepancies between the model’s predictions and actual battery performance, especially under varying operating conditions or as the battery ages and experiences degradation. This difficulty in capturing the full spectrum of real-world behavior limits their effectiveness in reliably identifying nuanced faults.

While data-driven methods offer a compelling path toward scalable battery fault diagnosis, their reliance on correlations within data often obscures the underlying reasons for failures. These techniques, such as machine learning algorithms, can identify patterns indicative of a fault, but struggle to pinpoint the specific degradation mechanisms at play – whether it’s lithium plating, electrolyte decomposition, or active material loss. This lack of mechanistic understanding introduces vulnerabilities; seemingly similar fault signatures could arise from entirely different causes, leading to misdiagnosis and inappropriate corrective actions. Consequently, data-driven approaches may exhibit limited generalization capability when faced with battery chemistries, operating conditions, or aging profiles not represented in the training dataset, hindering their deployment in real-world applications requiring consistently reliable and robust performance.

BatteryAgent: A Hierarchical System for Fault Detection

BatteryAgent represents a new approach to battery fault detection through a hierarchical framework that combines multiple analytical techniques. Existing methods often lack the ability to effectively integrate raw data with complex reasoning; BatteryAgent addresses this by systematically layering feature engineering, machine learning, and Large Language Model (LLM) inference. This integration aims to improve both the accuracy and interpretability of fault diagnosis, moving beyond simple detection to provide insights into the underlying causes of battery degradation or failure. The framework is designed to leverage the strengths of each component – feature engineering for physically relevant inputs, machine learning for pattern recognition, and LLMs for contextual reasoning – to overcome the limitations of traditional, single-method approaches.

The Physics Perception Layer processes raw battery sensor data – specifically Voltage, Current, and Temperature – to generate a set of electrochemically-grounded features. This transformation moves beyond direct use of raw values by calculating metrics such as State of Charge (SoC), State of Health (SoH), impedance, and internal resistance. These calculated features represent physical parameters directly related to the battery’s electrochemical processes and degradation mechanisms. By providing these physically-informed inputs to subsequent layers – namely the Detection & Attribution Layer – the framework enhances the accuracy and reliability of fault detection and diagnosis, as the model operates on data with inherent physical meaning rather than abstract sensor readings.

The Detection & Attribution Layer employs a Gradient Boosting Decision Tree (GBDT) model for fault identification, leveraging its capacity to handle complex, non-linear relationships within the feature space. Following fault prediction, SHapley Additive exPlanations (SHAP) values are calculated for each feature, providing a quantitative assessment of its contribution to the model’s output. These SHAP values decompose the prediction to show the impact of each feature, enabling a detailed understanding of the factors driving fault detection and improving the interpretability of the model’s decisions. This approach facilitates not only identification of battery faults but also pinpointing the specific sensor data most indicative of those faults.

Reasoning with Language Models: A Holistic Diagnostic Approach

The Reasoning & Diagnosis Layer utilizes the DeepSeek-R1 Large Language Model to synthesize detailed diagnostic reports. These reports are generated by processing the feature contributions identified by the preceding Detection & Attribution Layer; the LLM receives quantified data regarding which sensor measurements most strongly indicate a particular fault condition. DeepSeek-R1 then interprets these feature contributions and formulates a natural language report detailing the identified issue, the supporting evidence from the sensor data, and potential implications. This process allows BatteryAgent to move beyond simple fault detection and provide a reasoned explanation of the system’s current state based on the analyzed data.

The Numeric-to-Semantic Bridge is a critical data transformation component within the Reasoning & Diagnosis Layer. It functions by converting raw, quantitative data – including sensor readings such as voltage, current, and temperature, as well as the numerical feature importances generated by the Detection & Attribution Layer – into descriptive, human-understandable diagnostic statements. This translation process utilizes predefined mappings and rules to associate specific numeric ranges and feature contributions with corresponding fault conditions, component degradations, or potential root causes. The output of this bridge is not simply a label identifying a fault, but a contextualized explanation that details the observed condition in natural language, facilitating understanding for a human operator or automated system.

BatteryAgent utilizes the reasoning capabilities of its integrated Large Language Model to move beyond simple fault identification. Upon detecting anomalies such as Internal Short Circuit or Thermal Runaway, the system generates diagnostic reports that include not only the identified fault, but also contextual explanations detailing the likely contributing factors. This includes analysis of sensor data and feature importance scores to infer potential root causes, providing users with insights into why a fault occurred, rather than simply that it occurred. The system’s output aims to facilitate faster and more effective troubleshooting and repair processes by offering a reasoned explanation of the observed battery behavior.

Vehicle 405 exhibited varying fault severity across 50 charging segments, with the mean rating and standard deviation indicating a range of <span class="katex-eq" data-katex-display="false">0-5</span> for fault intensity.
Vehicle 405 exhibited varying fault severity across 50 charging segments, with the mean rating and standard deviation indicating a range of 0-5 for fault intensity.

Validation and Impact: A Paradigm Shift in Battery Management

Rigorous validation confirms BatteryAgent’s exceptional ability to identify battery faults, demonstrated by a state-of-the-art Area Under the Receiver Operating Characteristic curve (AUROC) of 98.6%. This metric quantifies the system’s capacity to distinguish between normal and faulty battery operation with remarkable accuracy. A higher AUROC score indicates superior performance, and this result positions BatteryAgent as a leading solution for proactive battery health monitoring. The system consistently minimizes false positives and false negatives, enabling timely interventions and preventing potentially hazardous situations – a crucial advancement in battery management technology.

The implementation of BatteryAgent demonstrably impacts operational expenditure, yielding a substantial 59.4% cost reduction. Prior to its deployment, average operational costs for battery management reached 229 CNY; however, BatteryAgent successfully lowered these expenses to just 93 CNY. This improvement stems from the system’s ability to preemptively identify and address potential battery faults, minimizing downtime and the need for costly reactive maintenance. The economic benefits highlight the practical value of BatteryAgent, offering a compelling return on investment through optimized battery performance and extended lifespan.

BatteryAgent represents a novel approach to battery management by successfully integrating the strengths of both data-driven and physics-based modeling techniques. Traditionally, battery diagnostics have relied heavily on either analyzing historical data with machine learning or simulating battery behavior using complex electrochemical models; however, BatteryAgent uniquely combines these approaches. This synergy allows the system to not only identify developing faults with greater accuracy, but also to predict future performance and proactively implement preventative measures. By understanding the underlying physical processes and learning from real-world operational data, BatteryAgent extends battery lifespan, minimizes the risk of failures, and ultimately enhances the overall safety and reliability of battery systems-moving beyond reactive maintenance to a paradigm of predictive, proactive management.

The pursuit of intelligent battery fault diagnosis, as demonstrated by BatteryAgent, echoes a fundamental principle of systemic understanding. The framework’s synergy-combining physics-informed interpretation with LLM reasoning-highlights that comprehensive solutions arise not from isolated advancements, but from the harmonious interplay of components. This aligns with the notion that structure dictates behavior; the carefully engineered features and interpretable machine learning models provide the essential scaffolding upon which the LLM can effectively reason. As David Hilbert stated, “In every well-defined mathematical problem, there is a method of solution.” BatteryAgent exemplifies this, offering a methodical approach to a complex problem, showcasing how clear ideas, rather than sheer computational power, drive scalable and insightful results in battery management systems.

Where Do We Go From Here?

The pursuit of intelligent battery fault diagnosis, as exemplified by BatteryAgent, reveals a recurring truth: accuracy, while desirable, is a superficial metric without a corresponding understanding of why a diagnosis is made. The framework elegantly marries physics-informed feature engineering with the representational power of large language models, yet this very synergy highlights the field’s ongoing dependence on handcrafted knowledge. Future iterations must grapple with the question of autonomy – can the system learn the underlying physics itself, diminishing the need for explicit domain expertise? The current architecture, though demonstrably effective, still relies on a pre-defined feature space, subtly limiting its capacity to detect novel failure modes.

Furthermore, the reliance on SHAP values, while providing a degree of interpretability, offers only a localized explanation. The system identifies what features contribute to a diagnosis, but rarely how those features interact within the complex electrochemical processes at play. A truly holistic approach demands a model capable of reasoning about causality, not merely correlation. The challenge lies in constructing a system that doesn’t simply report symptoms, but articulates a coherent narrative of the battery’s degradation.

The immediate gains in diagnostic accuracy are noteworthy, but the long-term value resides in the potential for proactive maintenance and lifespan prediction. This requires a shift from reactive fault detection to anticipatory health management. Good architecture is invisible until it breaks, and only then is the true cost of decisions visible.


Original article: https://arxiv.org/pdf/2512.24686.pdf

Contact the author: https://www.linkedin.com/in/avetisyan/

See also:

2026-01-02 04:57