Study On Filling Process Of Lithium-ion Battery Electrolyte Based On Ultrasonic Imaging

The global depletion of resources and the rapid development of the electric vehicle market requires advanced energy storage technology,especially for lithium-ion battery applications.As the core part of the battery,the electrolyte is not only an important medium for ensuring ion transmission but also an essential basis for the battery to obtain high voltage and excellent specific energy.Hence,the physical and chemical properties of the electrolyte,as well as the wetting ability to electrodes,influencing the performance of the batteries directly.As far as the current research status is concerned,the characterization and analysis methods of the electrolyte filling process between the pole piece and the diaphragm which can build an intuitive guidance model for the whole process are devoid.But only judging from industrial production experience is high-cost and deficient.Ultrasonic testing as the means of non-destructive approaches has the advantages of accurate positioning,rapid detection,high sensitivity and low cost which can offer innovative research ideas and methods to explore the filling process.In this article,ultrasonic non-destructive testing technology is applied to build the ultrasonic non-destructive testing imaging system for visualizing the filling process of electrolyte successfully.Based on the further calibration of imaging effect and optimization of system parameters,the correlation model of electrolyte infiltration process with time and injection was established.The results prove that the ultrasonic non-destructive testing imaging system can give a distinct graphic about the dynamic process of electrolyte infiltrating electrode and diaphragm,imaging effect is good the result is favorable.And simultaneously the imaging results can be used to calculate the time required for the electrolyte to wet the infiltrated pole piece and diaphragm completely.Upon this basis,the influence between atmospheric and vacuum injection conditions about the filling process of electrolyte was compared.It shows that vacuum injection can greatly shorten the infiltration time,enhance the infiltration efficiency and promote the infiltration effect.