Detection of dissolved metal ions in Li-ion battery electrolytesPaljk, Tina (Avtor) Dominko, Robert (Mentor) Li-ion batterybattery degradationtransition metal dissolutionmanganesesensorprinting technologyimpedance spectroscopyThe increasing world's dependence on batteries demands a more precise and consistent monitoring of the battery state in order to increase its quality, reliability, lifetime and safety (QRLS). Conventional monitoring of Li-ion battery performance is carried out by combining empirical measurement of the extrinsic parameters with multipart modelling and approximation algorithms. A step forward would be enabling more reliable built-in sensing systems that allow collecting direct information, such as a degree of material degradation. The sensing technologies should be designed in a way of monitoring the most detrimental process for the battery cell. Transition metal dissolution is one of the more severe degradation processes affecting the performance of the whole Li-ion battery cell. It can be accelerated through different mechanisms, and its monitoring has been a topic of several studies in recent decades. In the present work, we looked for an approach for detection of dissolved transition metal ions. The solution was found through a built-in electrochemical sensor with scavenger moieties. We demonstrated that manganese ion-imprinted polymer (Mn(II)-IIP) deposited between two electrodes printed directly on the separator can be used as a sensing layer. The resistance changes of this sensing layer due to the coordination of the ion-imprinted polymer with dissolved manganese ions are monitored by electrochemical impedance spectroscopy. The sensor’s electrodes and sensing layer remain stable within the voltage range of battery cycling over a longer application time. The sensor performance was validated in the single-layer pouch cell using Li|LiMn2O4 chemistry. The sensors printed on the separator do not significantly alter the current production technology and, most importantly, have a negligible impact on the cell energy density. The shown approach is universal and can eventually be extended to the detection of other degradation products in the electrolyte. Additionally, the use of the current printing technology permits large-scale commercialization. In summary, this work presented a simple solution for monitoring battery degradation via an electrochemical sensor integrated in the separator.20232023-03-28 14:55:00Doktorsko delo/naloga144987VisID: 12801COBISS_ID: 147023875sl