深空探测用锂离子蓄电池在轨管理策略研究

On Orbit Management Strategy of Lithium Ion Batteries for Deep Space Exploration

高轨卫星、深空探测器在工作周期内地影时间较短,储能电池长期处于搁置状态,而在存储过程中由于界面副反应的存在会导致持续的锂离子电池容量衰降,影响储能电池的使用寿命。通过dV/dQ曲线分析、交流阻抗分析和解剖分析发现在存储过程中活性Li损失是导致锂离子电池容量损失的主要原因,在100%SoC状态时还会导致电解液在负极表面的分解加剧,引起正极的界面膜阻抗RSEI和颗粒间接触阻抗RCR出现明显的增加。研究结果表明:深空探测器电源系统在存储期间为了减少过放电风险,并减少不可逆容量损失,应将蓄电池的荷电状态控制在20%SoC左右,并定期进行充电。

During the lifetime of Deep space detectors and GEO satellites,the batteries work occasionally and are kept in storage most of the time.The battery capacity would continuously decrease as the result of side reaction during storage.Through dV/dQ curve、EIS and cell disassemble analysis,the active Li loss is the main reason for capacity degradation.When the cell is stored at 100%SoC,the electrolyte decomposition on the cathode would cause the RSEI and RCR of cathode increasing significantly.To prevent the battery over discharge and reduce the irreversible capacity lost,the battery should be kept around 20%SoC and be charged regularly.