Bill Daniels wrote:
OK, so what would be wrong with using a 9V lithium smoke detector battery
that lasts 5 times longer than an alkaline? I use one of these as a backup
on my Borgelt B40 and I've never had to replace it.

The EDS likely has an internal power supervisor which is monitoring the
battery voltage, and triggers an alarm when the amount of remaining run
time drops below a threshold. The discharge profile for lithium
batteries is different from alkaline, the alarm may be triggered too
early, or too late...

Marc