After about four years, the two well-aged 12 V 9 A·hr batteries in the Belkin F6C1500 UPS gave up after a few minutes without line power, whereupon I swapped the UPS out for a new one.
The old batteries don’t have much life left in them (the date in the title should be 2021):
That’s with a 1 A load, rather than the 2 A I used earlier, as they’ll never be used for heavy loads again.
The new 7 A·hr batteries can power a 300 W incandescent bulb for 10 minutes before sounding the Low Battery alert, then another three minutes before shutting down. That’s about 12 A at 24 V, call it 2.6 A·hr from grossly overstressed batteries.
The Smell of Molten Projects in the Morning 
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