Inline X-ray computed tomography (CT) is a powerful inspection technique that can further reduce the risk of defects and recalls, compared with today’s 2D X-ray inspection techniques. Furthermore, when X-ray CT is integrated in cell assembly, defects can be automatically detected in real time to enable immediate corrective actions, thereby eliminating yield losses and quickening change control-type processes. However, to achieve the levels of inspection coverage, throughput and resolution necessary for high-volume battery production, a high-power X-ray source with a micrometer-sized X-ray spot is necessary. The Excillum MetalJet E1+ source makes this possible, achieving a full scan with micrometer resolution in just one second, or less.

An internal feature to be inspected during manufacturing of a battery is the anode overhang. The anode should be dimensioned to overlap the cathode. To produce this with repeatability puts high demands on the manufacturing and process precisions. To inspect this with precision in prismatic battery cells, X-ray CT is a pre-requisite. Furthermore, to have a 3D model of each produced battery cell can be very helpful for forensics in case a battery cell fails in the field – in order to minimize a recall to an as small volume as possible.

The following images, of pouch, prismatic and cylindrical cells, were captured in just one second, or less, by an Excillum MetalJet E1+ X-ray source, making CT highly suitable for inline and end-of-line inspection during high-volume manufacturing.