My understanding is that material composition can make a CT scan take a really long time. It makes sense to me that scanning a battery would be pretty slow, given what they're made out of.

I just assumed it would be impractical due to physical changes of the object from multi-hour exposure to X-ray energy.

I don't think ionizing atoms inside a battery will harm it. They don't have DNA.

I don't know about batteries, but ionizing radiation can definitely permanently damage microelectronics, and those don't have DNA either.

Thankfully functionality isn't usually necessary to get a successful scan, unlike living targets.

It can, yes, but batteries also don't have microelectronics.

Metal objects don’t change that much due to the radiation.

That is possible, especially for very high resolution scans and dense materials.

I work with (other) desktop microCT scanners and the longest scan we did took longer than 40 hours.