The presence of moisture on electrodes can have substantial effects on the overall performance of a lithium-ion battery. Several processes, including reactions with the conducting salt during operation can lead to this reduction in performance, as well as mechanical problems such as swelling.

Removing this moisture from electrodes is therefore an incredibly important aspect of the manufacturing process, as is having a method for the determination of moisture. Currently, Karl-Fisher methods are the most common techniques for the determination of water in electrode samples. However, there are several disadvantages to this method including the need to handle the sample before analysis, allowing for the introduction of more moisture into the sample.

Thermogravimetric analysis-mass spectrometry, on the other hand, allows for analysis of these samples without the need of extensive preparation or chemical reagents.

An arguably more important aspect of TG-MS is that mass spectrometers have the capability of measuring a wide range of ion fragments, allowing for a range of different species to be analyzed with no significant changes in experimental parameters. Furthermore, thermogravimetric analysis provides information regarding the temperature at which species adsorb and desorb from the surface of the electrode.

This work aims to describe the use of thermogravimetric analysis hyphenated to mass spectrometry (TG-MS) for the analysis of water and carbon dioxide on both anode and cathode samples, exemplifying the vastly different adsorption/desorption behaviour that these materials can demonstrate.