Investigating the temperature behaviour of battery cells has become an important part of today’s research and development. This is because the temperature profile of a cell changes during cycling after being aged in either a cyclic or a calendaric way. By using the diagnostic technique DTV, which uses measurements that can be done in-operando, new possibilities are opened up. Especially since only temperature and voltage readings are necessary.

In this work, similar battery cells are aged in different ways regarding cyclic and calendaric aging. Afterwards, all cells are subjected to the same check-up measurement so that comparable measurement results are gained. Simultaneously, the temperature profile is recorded using a probe located on the cell. The data collected is then evaluated using two different analysis techniques: The characteristic points of the well-known DVA (differential voltage analysis) curves are compared to the DTV (differential thermal voltammetry). This makes it possible to establish correlations between the changing curve characteristics and the capacity loss, and therefore the aging of the respective cell.

The aim of this work is to find correlations between the temperature behavior of aged cells and their SoH by looking at the corresponding DVA and DTV analyses. With the help of these dependences, conclusions can be drawn about the aging of the cells. This opens up the possibility of determining the SoH of battery systems in different application areas (for example: buses) by only looking at their respective charging cycles (for example: recharging during downtime).