Latitude 5520, 2 different laptops, *exact same* FULL CHARGE CAPACITY?
Hi, I am baffled. I have two different refurbished Latitude 5520 laptops. I have installed clean Windows 11 Pro with all the latest updates & bios updates (I believe current is 1.52 from august). However bios claims battery conditions poor & diagnostic fails on battery. powercfg / batteryreport gives exactly similar outputs. Batteries are the same but there is no way full charge can be the same on two different laptops. I suspect bios / firmware issue?
Those serial numbers are so close together that the cells they're made from probably came from the same batch, meaning their performance will have been similar.
And at five years old, they're due for replacement.
You can try resetting the embedded controller (disconnect AC power and battery, hold the power button for 30 sec, and reassemble the system and re-run the powercfg command). If nothing has changed, replace the batteries.
@ejn63 For this refurbishing company that would be bad news. As they promise >70% batteries. I will DOA them (got already one DOA accepted). By simple mathematics there is a
0,0016 % chance that two different laptop batteries have exactly the same remaining capacity.
Jus to make things more interesting I purchased third laptop (same model) from *different* refurbishing company. At least this has different readings, of course battery model is different.
ejn63
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Posted August 26th, 2026 17:05
Those serial numbers are so close together that the cells they're made from probably came from the same batch, meaning their performance will have been similar.
And at five years old, they're due for replacement.
You can try resetting the embedded controller (disconnect AC power and battery, hold the power button for 30 sec, and reassemble the system and re-run the powercfg command). If nothing has changed, replace the batteries.