Health condition assessment of satellite li-ion battery pack considering battery inconsistency and pack performance indicators

Abstract

Assessing the health condition of satellite li-ion battery pack accurately is critical for determining the safety of satellite power supply and ensuring that satellite satisfies its service life. Since the limitations of space environment make satellite battery special in operation and maintenance, misjudgments may occur when using existing assessment methods. To solve this problem, a novel health condition assessment indicator system that integrates battery inconsistency and pack performance indicators is built according to the performance requirement of battery pack. Based on the typical strategy of satellite battery pack performance degradation management, equalization and bypass state are employed as factors to make assessment result more accurate and comprehensive. Then, a method based on ER (evidential reasoning) and BRB (belief rule base) is proposed to achieve inconsistencies fusion and rule-based assessment. And the results can be expressed as belief degree distribution or score. Finally, the health condition of a certain type of in-orbit satellite's li-ion battery pack is assessed using telemetry data. The results are consistent with the battery's actual working state, which proves the effectiveness of the proposed method.