The non-invasive investigation of lithium-ion batteries is of great importance, e.g. for improvement of electrode materials or monitoring the state of health (SOH) in stationary or mobile applications. Electrochemical impedance spectroscopy (EIS) is a powerful tool for this task. Once the predominant processes in the impedance spectra are assigned to their corresponding electrode (i.e. anode or cathode), a tracking of both electrode's SOH becomes possible. In a previous work, this assignment has been performed. Two predominant processes were found: the impedance of the solid electroly interphase (SEI) and the NMC's charge transfer. In this work, this information is used for a non-invasive yet separate investigation of anode and cathode degradation throughout aging. Cells have been aged for about 700 days (calendric aging) or about 3000 full cycle equivalents (cyclic aging) at three different operating points each. A combination of impedance spectra analysis, differential voltage analysis (DVA) and post mortem analysis (PMA) determines the main aging mechanisms. Calendric aging: SEI-growth, CEI-growth, cathode-dissolution. Cyclic aging: anode's and cathode's particle-cracking, cathode-dissolution and possibly CEI-growth.

锂离子电池的非侵入式研究非常重要，例如对于改善电极材料或监测固定或移动应用中的健康状态（SOH）。电化学阻抗谱（EIS）是完成此任务的强大工具。一旦将阻抗谱中的主要过程分配给它们相应的电极（即阳极或阴极），就可以跟踪两个电极的SOH。在以前的工作中，已执行了此分配。发现了两个主要过程：固体电相（SEI）的阻抗和NMC的电荷转移。在这项工作中，此信息用于非侵入性但单独研究整个老化过程中阳极和阴极退化的情况。电池已经在每个三个不同的工作点老化了约700天（日历老化）或约3000个完整周期的当量（循环老化）。阻抗谱分析，差分电压分析（DVA）和事后分析（PMA）的组合确定了主要的老化机理。日历老化：SEI增长，CEI增长，阴极溶解。循环老化：阳极和阴极的颗粒开裂，阴极溶解以及可能的CEI增长。