You can buy the Timekeeper IC here:
https://www.ebay.co.uk/itm/271121190063
Please double check to see if the chip is EXACTLY the same as other CD-i models differ.
I have two original CD-i 210 units, these require the timekeeper chip listed.
I have bought two and both work ok.
No need to hack a CR2032 on top of the old chip.
Again, please double check your chip is the same before ordering.
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https://www.youtube.com/watch?v=0DtAaCXaJHg