Unsolved
1 Rookie
•
20 Posts
0
11783
September 6th, 2022 23:00
Primarily AC use, What Does it Actually Do!?
I've already searched for an answer but couldn't find it, so I ask you members and hopefully we'll get a definitive answer from DELL itself!
What does actually do if I select "Primarily AC use" in the BIOS? ...yes I pressed F1 and read the help there also selected the option and tried to see what it does but it seems it does nothing!
No Events found!
Chino de Oro
9 Legend
•
8.1K Posts
1
September 7th, 2022 05:00
My understanding, primarily AC use is a charging scheme that can prolong the health of your battery. It will stop charging when the battery power level reached around 85%. But it will reporting that the battery is fully charged (100%). That way, it prevents top off charging.
Fast charging and prolong a maximum charged level often shorten the life of lithium battery. Also if you install a long life battery (from precision line), charging options will not be available.
bresty
1 Rookie
•
20 Posts
0
September 7th, 2022 06:00
I believe you are either right or my new battery is already faulty...I tried "Primarily AC use" and then when it reached 100% removed the cable, the laptop reached approx 25% (but in this mode it is actually 15% right??) and after very short time it suddenly it went to 7% and turned off...25 - 15 = 10 (I used the laptop a little and it reached 7), anyway weird and unclear mode will update when I better check it out.
bresty
1 Rookie
•
20 Posts
0
September 9th, 2022 00:00
I looked in the bios and the battery is charged like windows says, is this -15% actually kept so secret?
Chino de Oro
9 Legend
•
8.1K Posts
0
September 9th, 2022 07:00
No, it's no secret that primarily AC use mode extends battery life by lowering the charge threshold. Here is the description from battery settings:
Found similar answer from another Community Accepted Solution
The practice is widely used according to this report.
bresty
1 Rookie
•
20 Posts
0
September 9th, 2022 18:00
correction:
I tried again I can confirm that with this mode when on battery and you reach around 30% the battery suddenly drops the amount of about 20% that is it goes to 10%.
What makes this mode difficult to understand is that the battery gets charged fully to 100% but taking into account this sudden drop when it reaches about 30% it tells there is something unclear about this mode