If I remember correctly this is an Ensoniq product. I owned the VFX, SD-1 and TS12. The VFX battery went on me back in the 90's. When it went I lost anything that was "user"; user presets created, programs, etc.. If you are using presets that were delivered by the instrument itself with zero adjustments to those presets, then I'd say no. How do the presets and the memory cards (mine were cartridges, not cards) interact? I don't recall being able to store user-defined presets on the cartridges, just the programs themselves. The SD1 and TS12 also had a 3 1/2" drive that you could save to and load from, the VFX did not, just the cartridge. My VFX battery was soldered to the board. When I replaced the battery I also soldered in a battery holder so that in the event the battery went a 2nd time the battery replacing process was much easier. As the KS-32 was around the time of the VFX/SD1 in the product life cycle, I don't know if a battery holder was installed. If you are going to hang on to the keyboard and you are handy with a soldering iron, I might opt to replace the battery and install a battery holder at the same time.
Here is a interesting article on a solution:
A long, long time ago, I obtained a Midi Workstation, called an Ensoniq KS-32. I'm still thankful for the great deal I got on it. I'm als...
blog.vollink.com
Lithium 3-volt battery, with solder tabs. This battery must be soldered to a circuit board, and unless you are experienced with a soldering iron, you may not want to tackle this job. If you do, beware that overheating the battery can cause it to explode; make quick solder joints and use a...
www.syntaur.com