Faced an unexpected phenomenon. The batteries in UPS are tightly fused together.
The batteries were in the APC Smart UPS 700, bought on Avito for 600 rubles five years ago (https://ammo1.livejournal.com/712208.html).
Only the analyzer of chemical current sources АСК2.5.10.8, which consumes no more than 50 watts, was connected to the UPS.
Some time ago, the UPS started beeping intermittently, signaling problems with the batteries. I had no time for him, and so he worked for another week, or even two.
When I turned it off and opened the battery compartment to take out the batteries and measure the voltage across them, I found this.
The second battery cracked through and through in two places.
The softening point of ABS is about 110 degrees. It is completely incomprehensible what caused the batteries to be so hot. Judging by the deformation, the batteries were heated not from the inside, but from the outside.
Above them is a board with UPS "brains", there is nothing to bask in there. The entire power section is located behind the iron wall.
The batteries are, of course, the end. It's a pity, because they were expensive and good Delta and CSB. The voltage on the Delta is now 3.7V, on the CSB it is 4.9V.
Interestingly, UPS worked until I turned it off. But when I tried to turn it on again to figure out what was heating up and why, it no longer turned on.
It's good that the entire UPS is made of iron. If something in it heated up to 100, and maybe 150 degrees, it could have heated up to a higher temperature, and if the case were plastic, a fire could have happened.
© 2021, Alexey Nadyozhin
For ten years I have been writing every day about technology, discounts, places of interest and events. Read my blog on the site ammo1.ru, v LJ, Zen, Mirtesen, Telegram.
My projects:
Lamptest.ru. I test LED lamps and help figure out which ones are good and which are not so good.
Elerus.ru. I collect information about domestic electronic devices for personal use and share it.
You can contact me in Telegram @ ammo1 and by mail [email protected].