Chemicals | Rotational Viscosity Testing in Battery Cell Manufacturing

The main parts of a battery cell are the electrodes (cathode and anode), separator and electrolyte. Various types of battery cells are produced for a wide application area. However, lithium-ion batteries have become the mainstream of energy storage devices in the current market. 

This application report shows some example viscosity measurements of electrolyte solutions and separator coating material with the rotational viscometer ViscoQC. Furthermore, the importance of viscosity testing of electrode slurry is discussed.

The performance of the charge and discharge rate of a rechargeable battery, that is the ion transport, is characterized by the ion conductivity, which depends on the viscosity and the dielectric constant. The viscosity of the solvent, in which the ion salt is dissolved, affects the mobility of ions; the mobility is inversely proportional to the viscosity.

Three different samples have been viscosity-tested with different instrument configurations. The tested samples are two different electrolyte samples and an aluminum oxide coating.