i'm not sure how recent this is or exactly what models it effects (i have an inspiron) but there's a recall on the batteries from dell laptops.
the guy who fixed my computer said that we need to call dell and give them the serial number from the battery to find out of it's defective or not... i suggest that anyone here with a dell laptop do the same thing.
he said that the defective batteries can suddenly stop working, overheat, or even explode or catch on fire.
edit: here's some more info https://www.dellbatteryprogram.com/
Well over a year old news
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