RTC Module Chip Extract

I saw this video by Necroware earlier, about the possibility to extract the contents of the RTC modules found in older PCs. I have tried it myself and it is indeed possible to use hot air to weaken the resin and break off the external casing. This is an alternative to drilling holes in the side of the RTC module as shown in an earlier post to expose the battery contacts.

Inside a module there will be the actual RTC chip, a crystal and a (probably dead) battery:

Here is an example where a large CR2016/CR2032 battery holder was added:

On another RTC module some of the pins were broken off, extracing the chip made it possible to solder the remains onto some pin socket connector rows. A smaller CR1220 battery holder was added: