So...my post early about 'device storage' was misguided. Between the time I noticed the high battery drain from a process & actually posted about it, in my mind I changed the name from 'security storage' to 'device storage'. Anyway, having spent some quality time with Google yesterday, I find that having security storage as battery eater, while not common, does occur on a number of devices. I just wish I could figure out what app triggers it so I could get rid of it without doing a FDR & re-installing app by app.