HP 4195A battery

[rumreich]

I acquired an HP 4195A that had been in storage for a few years and it appears to work properly in every way. 

I thought I'd preemptively replace the backup battery A6BT1 and ordered a COMP-34SPC 2.4V NiCad.

When I pulled the A6 card out, I discovered that the battery had been replaced with a TADIRAN 3.6V lithium battery and R28 was clipped on one side.  This is a non-rechargeable battery and R28 is a series resistor in the battery charging circuit.

Is anyone familiar with this approach?  I can't decide whether to leave it as-is or install the NiCad and resolder R28.

Thanks in advance for any comments.