My mum's laptop has started draining the battery super fast, going from 100% to empty in just a few minutes. I tried running a battery report through the command prompt, and it shows that the design capacity is 40,000mWh but the full charge capacity is only 4,800mWh. It's clear something is wrong, but I'm not sure what the issue could be. This problem came out of nowhere; she has had the laptop for 5 years with no issues until the last two weeks. It's a Dell Inspiron 5406, and I'm open to providing more details or sharing the battery report if needed.
2 Answers
It sounds like the battery might just be dead. If it's only holding a small fraction of its full capacity, a replacement could be necessary. These batteries do wear out over time, especially if the laptop has seen some use.
Keep in mind that laptop batteries typically last about 2-5 years. It’s possible that when it claims to be at 100%, it’s really only at around 12%. But I get your concern about the sudden drop in capacity, that’s definitely unusual!
Yeah, it's frustrating because everything seemed fine until recently. My own laptop from the same time still holds its charge way better.

Totally agree with you! That’s usually the best fix in situations like this.