State of Health Estimation for Satellite Batteries Based on the Charge Curves

Lithium ion batteries are attracting more attention for excellent performance. State of health estimation and remaining useful life prediction are critical for optimization and safety of satellite batteries. However, there are still some drawbacks for existing characterization method due to the unachievable measurement of capacity or resistance for batteries used in satellites. This work presents a new health indicator to evaluate the degradation of satellite batteries based on the charge curve. Linear correlation between the health indicator and cycle number is found. The indication performance of health indicator extracted with charging data and discharge data is compared. And the charge capacity ratio of constant current and constant voltage process is analyzed and, similarly, a linear relationship between the ratio and cycle number is found. Then grey model and linear regression method are utilized to estimate the health state and predict the life of three batteries operated with different depth of discharge. The validation results demonstrate that our new health indicator is feasible for the health state estimation and life prediction of .satellite batteries