Strange battery behaviour MVS MV1C

[Max...]

Picked up a nice MV1C MVS MOBO last week - original battery pretty dead so popped in a brand new Maxell ML2032 (correct type - rechargeable lithium manganese 3v - obviously slightly less capacity than the OEM 2430). Checked it's voltage when opened at 2.8v.

Installed it (pcb tabbed type) all good but after 10 mins powered up (Jamma 5v running at 5.03v) voltage measured across the terminals showed 1.75v and after an hour 1.15v and dropping...

Weird? Is the battery fooked, is it not really a ML type?

 

[Max...]

Hmm, seems a known issue:

MV1C problem with battery

I made the battery mod on a MV1C board that I purchased recently, and realise that everytime I turn on the board, no data is store (highscores, unibios config, etc ...) I did not check how the board was doing presiously with the old stock rechargeable battery. I use a brand new CR2032 (3,2 V)...

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