Dynamic Core Temperature Reconstruction for Transient Swelling Deconvolution in Prismatic Modules
Deconvoluting swelling requires dynamic internal thermal reconstruction to separate reversible expansion from heat driven volume growth.
Battery State of Health
Meaning
Performance metric representing the ratio of current full charge capacity to the original rated capacity of a secondary cell. Monitoring battery state of health helps determine when a pack no longer meets the operational requirements of its application. This figure provides a clear view of the total aging of the chemical system.
Capacity Retention
Discharge testing at a controlled rate provides the most accurate measurement of this value. Measurement of battery state of health involves comparing the delivered amp hours to the factory specification.
Impedance Deviation
Resistance within the cell layers increases as the electrolyte and electrodes degrade over time. While capacity measures the total energy stored, the impedance aspect of battery state of health indicates how much of that energy is lost as heat during high power events. High resistance can limit the ability of an electric vehicle to accelerate or fast charge effectively.
This measurement is often used in real time estimation because it can be calculated from current and voltage fluctuations during normal operation without requiring a full discharge.
Asset Valuation
Residual price for used batteries depends heavily on the remaining life of the cells. A high battery state of health allows a used pack to be sold into secondary markets for stationary energy storage.