X-ray computed tomography (CT) gives engineers a way to inspect the inside of an electric vehicle (EV) component without taking it apart. The technology creates a three-dimensional view of an assembled part so internal features can be examined while their original position and condition are still intact.
Sebastian Ahling, Ph.D., Staff Research & Development Engineer, Lumafield
This can be particularly useful in EV development, where batteries and power electronics are becoming more tightly integrated and harder to evaluate through conventional teardown alone.
CT can help engineers see internal geometry before deciding where destructive testing is necessary. It can also provide added context when investigating thermal performance or a component failure.
In Part I of this interview, Sebastian Ahling, Ph.D., staff research and development engineer at Lumafield, discusses how CT can be used to evaluate EV components in their assembled state. He explains what internal imaging can reveal that a teardown may miss, how it can inform thermal analysis, and where the technology fits into benchmarking, validation, and failure analysis.
Part II will look more closely at what internal component layouts can reveal about EV design choices and how engineers should interpret relatively simple or conventional architectures. Ahling will also discuss the limits of CT and how inspection requirements are changing as EV systems become more integrated and operate at higher power levels.
Here’s what Ahling has to say…
How can imaging-based inspection help engineers evaluate EV components without taking them apart?
The biggest advantage of CT is that you can inspect a component in its assembled state. You can see how parts are positioned relative to each other, how conductors are routed, how connectors are seated, where adhesives or potting materials are applied, and how mechanical and electrical systems share the available space.
That matters because disassembly changes the thing you’re trying to understand. Fasteners come out, seals relax, cables move, and delicate structures can be damaged. With CT, you can capture the assembly first and then decide whether a teardown or cross-section is needed. For something like a battery cell, that means looking at electrode alignment, winding geometry, tabs, and internal deformation before physically opening the cell.
What can internal inspection reveal that a conventional teardown might miss?
CT imaging reveals the internal anode and cathode layers of a lithium iron phosphate (LFP) battery cell, including variations in electrode alignment. (Image: Lumafield)
A teardown gives you excellent access to individual parts, but it can lose the original spatial relationships between them.
CT is particularly useful for interfaces: a small air gap under a thermal interface material, a connector that isn’t fully seated, a void in an adhesive bond, a bent conductor, or a deformation inside a battery cell.
It’s also useful when the failure itself is fragile. If something cracked, shifted, delaminated, or deformed, taking the assembly apart can disturb the evidence before you know where to look.
I generally think of CT and teardown as complementary. Scan first to understand the assembled system and identify areas of interest. Then use the scan to make the destructive work much more targeted.
How can imaging help engineers assess thermal design inside EV components?
CT doesn’t measure temperature, but it can tell you a lot about the geometry that controls heat flow.
You can look at the contact between heat-generating components and heat sinks or cold plates, the thickness and coverage of thermal interface materials, coolant channel geometry, air gaps, potting, and how tightly different components are packaged.
In power electronics, for example, a small void or poor contact at a thermal interface can matter a lot even if everything looks correct externally.
CT imaging provides a three-dimensional view of components and interconnections inside an EV charger without requiring disassembly. (Image: Lumafield)
What CT can’t tell you by itself is whether that thermal system actually performs under load. You still need temperature measurements, thermal cycling, electrical testing, and often simulation. CT gives you the physical geometry to help explain the thermal behavior you measure elsewhere.
Where does internal inspection fit into EV benchmarking, validation, or failure analysis?
For benchmarking, I like CT near the beginning of the process. You can inspect an intact competitor component, understand the overall architecture, take measurements, and identify areas worth investigating before starting a teardown.
For validation, it can be used to compare the built hardware against the intended design and to look for things like assembly variation, internal clearances, voids, deformation, or cell alignment.
Failure analysis is where the sequence becomes especially important. If you have a failed unit, scanning it before opening it preserves the failure state. Ideally, you can also compare it with a known-good unit. Once you identify an anomaly, you can correlate it with electrical or thermal data and then section the part exactly where you need to. X-ray CT has been used this way to characterize internal battery damage without first destroying the cell.
In Part II of this Q&A, Ahling will discuss how CT can help engineers interpret EV component design choices as vehicle systems become more integrated.
Filed Under: Featured Contributions, Q&As, Test And Measurement