Lithium primary batteries are used for mission-critical systems where recharging is impractical, so understanding the safety and reliability of them is important. How primary Lithium batteries degrade during normal use has been tracked in real-time by a UCL-led team using sophisticated 3D imaging, giving a new way to non-invasively monitorperformance loss and guide the development of more effective commercial battery designs.

On the outside, the batteries look like they are doing their job normally but inside the structures are undergoing great change. Electrical activity is high in some areas of the cell, whereas it is low in others; layers of electrode material separate and crack. All of these changes in structure affect the flow of electricity and reduce the performance of the cell. The study, using cutting edge X-ray imaging techniques at The European Synchrotron (ESRF), shows the internal structural damage caused to batteries working under normal conditions in real-time.