基于多路径老化演化与热反应特性定量解析的电池生命周期安全性能评估与管理方法

Focusing on the two scientific issues of effects mechanism of multi-mode aging progress on the safety performance evolution for cell and material, and coupling relationship between module consistency, durability and safety evolution, this research is expected to make breakthrough on aging theory and testing verification under multi-level, multi-mode for material, cell and module, revealing the synergistic effect of the aging path and SOH of battery cells on thermal runaway characteristics. Evolutionary law for evaluating the module performance dispersion is investigated, and its coupling effects with thermal runaway performance and SOH are explored further. By equivalent thermal runaway evolution experiment triggered by micro-electrical abuse and internal short circuit, the quantitatively method is presented for describing the thermal runaway process with multiple inducements under different aging processes. Then, a safety boundary construction method based on internal short circuit recognition and thermal runaway forecasting model is proposed. Furtherly, a life cycle safety assessment method for battery pack characterized by low-frequency electrical characteristics and thermal characteristics is obtained. A systematic method of life cycle safety assessment and management methods for EV battery system will be set up based on the outcome of this research, which is expected to provide the basic theories and feasible solutions to improve the level of China's EV battery safety management technologies, and more importantly, provide the possibilities and guarantees to meet requirements of safe and reliable for the secondary utilization of decommissioned batteries from EV.

以车用动力电池生命周期安全性问题为研究背景，围绕多尺度老化对安全性演变的影响机理，以及模组一致性、耐久性和热失控特性演变之间耦合作用机制两个科学问题，通过材料组分、单体和模组多层面、多尺度老化对安全性影响的理论分析和试验验证，揭示单体老化路径与健康状态对热失控特性的协同影响规律；探索模组二维性能离散演变规律，揭示广义电池模组的性能离散度、热失控特性和健康状态的耦合影响机制。通过微电滥用和内短路触发等效热失控演变实验，探明不同老化历程的多诱因热失控过程定量描述方法。在此基础上，提出基于内短路辨识和热失控模型的安全边界构建方法，进而得到低频电特性与热特性协同表征的电池系统生命周期安全性评估方法。研究结果形成一套基于多影响路径老化演化与热反应特性解析电池生命周期安全性评估与管理方法，有望为我国车用电池安全管理技术显著提升提供基础理论和可行方法，为退役电池的梯次利用的安全可靠要求提供支撑与保障。

以车用动力电池生命周期安全性问题为研究背景，围绕多尺度老化对安全性演变的影响机理，以及模组一致性、耐久性和热失控特性演变之间耦合作用机制两个科学问题，通过材料组分、单体和模组多层面、多尺度老化对安全性影响的理论分析和试验验证，揭示单体老化路径与健康状态对热失控特性的协同影响规律；探索模组二维性能离散演变规律，揭示广义电池模组的性能离散度、热失控特性和健康状态的耦合影响机制。通过微电滥用和内短路触发等效热失控演变实验，探明不同老化历程的多诱因热失控过程定量描述方法。在此基础上，提出基于内短路辨识和热失控模型的安全边界构建方法，进而得到低频电特性与热特性协同表征的电池系统生命周期安全性评估方法。研究结果形成一套基于多影响路径老化演化与热反应特性解析电池生命周期安全性评估与管理方法，有望为我国车用电池安全管理技术显著提升提供基础理论和可行方法，为退役电池的梯次利用的安全可靠要求提供支撑与保障。