Electrolyte content is a pivotal determinant of the electrochemical performance and thermal safety of lithium-ion batteries. Yet, current measurement approaches—ranging from destructive offline analyses to expensive nondestructive imaging—suffer from latency, complexity, or insufficient accuracy, limiting their suitability for real-time and high-precision monitoring. Here, we present a nondestructive strategy for electrolyte volume assessment that integrates ultrasonic sensing with deep learning. An acoustic simulation model was first developed to characterize wave propagation in wetted versus unwetted regions, revealing distinct transmission pathways and providing direct validation of the underlying physical mechanism. Ultrasonic measurements on cells with varying filling levels further demonstrated that conventional acoustic features, such as peak amplitude, time-of-flight, and energy, show weak correlations with electrolyte volume. By contrast, ultrasonic imaging clearly captured the progressive shrinkage of wetted regions as electrolyte decreased. Leveraging this insight, a time-delay neural network (TDNN) was employed to extract nonlinear temporal features directly from raw waveforms, while a physics-informed correction—incorporating the prior knowledge that electrolyte reduction leads to shrinkage of wetted regions—was introduced to refine predictions. Experimental validation confirmed that the method achieves a stable prediction error within ±2% and demonstrates strong generalizability across different battery chemistries. This work provides a practical and accurate nondestructive pathway for electrolyte volume determination, offering new opportunities for quality control and health monitoring in lithium-ion batteries.
扫码关注我们
求助内容:
应助结果提醒方式:
