Lithium ion battery state-of-charge estimation method based on ultrasonic reflection characteristics and medium

The invention discloses a lithium ion battery state-of-charge estimation method based on ultrasonic reflection characteristics and a medium, and belongs to the technical field of lithium ion battery management.The method comprises the steps that a SoC-EOC curve representing the relation between the state-of-charge and shock wave energy of a lithium ion battery is obtained through testing; according to the SoC-EOC curve, constructing a differential battery acoustic response model of coupling current, state of charge and shock wave energy, and performing linearization processing; solving to-be-identified parameters in the differential battery acoustic response model by using a least square method to obtain a determined differential battery acoustic response model; combining the SoC expression under the coulomb counting method with the differential battery acoustic response model to obtain an acoustic response state space equation; and substituting the real-time current and the real-time shock wave energy of the