Detection of dissolved metal ions in Li-ion battery electrolyte

TINA PALJK; M. VICTORIA BRACAMONTE; TOMÁS SYROVÝ; ROBERT DOMINKO

Congreso; ISE Regional Meeting; 2022

International Society of Electrochemistry

The dissolution of transition metals, especially manganese, from the structure of the cathode active material is a significant cause of degradation and loss of capacity of Li-ion batteries. The dissolved metal cations migrate to the separator and to the anode surface, which can lead to the formation of undesired degradation products, thus altering the properties of the passive film on the surface of the anode. Hence it is essential to control and understand the dissolution of metal ions to monitor the degradation and aging of the battery itself. To investigate the dissolution of manganese from the spinel cathode material LiMn2O4, multiple half cells with the same configuration were prepared and cycled for different numbers of cycle. Using ICP-MS analysis, we determined the amount of dissolved manganese in the disassembled cycled cells.The aim of this research was to develop a sensor to integrate into the battery cell. This way we were able to in situ detect the manganese cations without changing the battery set-up itself. The sensor printed on the battery separator can monitor the dissolved metal cations in the electrolyte at a key location inside the cell.Experiments have shown that manganese dissolution occurs from the beginning of the battery´s use and that the dissolution is enhanced, when induced by electrochemical reactions.