14 batteries (i need bipolar rails) is alot.
It always seems like if you get a bunch of those separate cells they tend to leak, the more the worse. And charging is a super hassle, you need to remove 14 batteries... no thanks
And I don't want a switching converter. This is for low noise preamplifiers possibly working in the region of kHz. No matter how well designed it is, it will suck compared to a high voltage battery. I mean like parallel LT1028's or AD797's etc, for photomultipliers, preamps, portable RF equipment, oprical detectors, electrometers, other sensor boxes (microphone, etc). I tend to like to design these things to run at +-15V, which is the typical nominal datasheet value for precision op-amps. Nothing shits in my cereal more then single supply op-amp design.
If I was selling something I would make a specification to some kind of noise floor and possibly use a switching converter, but I don't want to fuck with that unless I was making some kind of fat profit. I want like fast to implement R&D equipment so I can focus on the things that matter. I can see using a switching converter for these things to turn into a disaster very easily.
Also how are those batteries safe? It looks like they sell complicated protection circuits for them?