Standard operating procedure for replacing a Lithium cell whilst maintaining power to the SRAM...
1. Buy a 2 cell AA or AAA battery holder with flying lead output for connection to a PCB.
2. Fit 2 cells in the holder
3. Solder the flying leads to the supply rails that the Lithium battery maintains (observing polarity)
4. Cut the lithium battery off of the PCB
5. Desolder the lithium battery pins
6. Insert the new Lithium battery and solder its pins.
7. Desolder the battery holder flying leads.
8. Job done
Note this is all done with the power to the equipment
OFF !
For the very nervous amongst you, you can usually insert a 1K resistor in series with the battery holder flying leads, though this is not normally needed in the real world.
This approach came from an OEM service manual and is not some 'hack' method
Aurora