Assessing Useful Remaining Life of Lithium (Li)-Ion Batteries After Deep Discharges

Global Technology Connection with its industrial/university partners (SAFT, Smiths Aerospace, Penn State University) proposes to develop the algorithms to determine the useful remaining life of lithium-ion batteries after a deeper than nominal discharge Working closely with cognizant JSF office and our industrial partners, feasibility study on whether remaining useful life algorithms can be augmented by accounting for depth and duration of discharges beyond normal ranges will be performed in Phase I. The prototype remaining useful life model parameters necessary to re-characterize current battery health assessments as well as future health predictions based upon depth and duration of discharges experienced during shipping, storage, or abnormal operating conditions will be enumerated. Strategy for collecting information required to update battery health status after deep and lengthy discharges during normal or abnormal operating conditions will be presented. This concept will be further characterized with the data furnished by our industrial partners/customer to demonstrate the feasibility of this concept. In Phase II, we will develop the detailed remaining useful life models to account for depth and duration of discharge beyond nominal levels. Cycle testing of representative cells or batteries to determine remaining useful life as a function of depth and duration of discharges beyond nominal will be conducted. Verification of the data collection strategy will be implemented and that data can be applied to update battery health status within the overall JSF architecture. In phase III, we will implement updated remaining useful life algorithms that address abnormal discharges by making any necessary modifications to software modules within existing PHM/CBM architecture.