Quadram Quadboard 1984 battery replacement

I recently bough an XT-class computer. Inside it had a 1984 model of Quadram Quadboard multi-function 8-bit ISA card.

Quadboard Quadram 1984 top with original Vatra battery

I noticed it had a soldered in Vatra Ni-Cd rechargeable battery on it. Those batteries often leak acid when fully discharged. The acid destroys PCB tracks and makes restoring a chore.

My cards battery didn’t leak yet, but I decided to remove it anyway.

Quadboard Quadram 1984 top - original battery removed

Quadboard Quadram 1984 bottom - original battery removed

I replaced it with CR2032 - a non-rechargeable lithium coin cell. I installed it in series with a diode I removed from a dead motherboard. The diode is probably schottky, since voltage drop is only about 0.3V.

Quadboard Quadram 1984 top - new battery closeup

Quadboard Quadram 1984 bottom - new battery removed

More infiromation, manual and drivers can be found here.