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Dell XPS 13 (9315) only charging at 20W, with dell 45W charger
XPS 13 9315
I have a Dell XPS 13 (9315) and using the standard issue USB-C Dell 45W charger. However it seems to be only charging at 20W.
See screenshot from BatteryInfoView:
and also screenshot from the My Dell app (Power Manager) taken slightly later: At 54% charged there is approx 20Wh remaining to get to full charge, with the app estimating it'll take just over 1hr = confirms 20W charging speed:
I was expecting the XPS to charge at 45W (per the charger rating) but am I missing something?
ejn63
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November 24th, 2023 14:47
That should be an 11.1 V battery, and at 43 WHr (current charge capacity of your battery as stated in your image),
43 Whr * (3600s /hr) = 154800 J * (1C/11.1J) = 13946 coulombs of charge required.
A lithium battery will charge at about 0.9 C/second, so
13946 C *(1 sec/0.9C) = 15500 sec or about 4.3 hours to fully charge.
Starting with your 20 Whr needed that's a little over 2 hours.
It is very possible to charge a battery faster than 0.9 C/sec, but the faster the charge rate the greater the strain on the battery. No, the charger isn't going to deliver the full charge capacity of the power supply to the battery (even if the adapter were 100% efficient, which it isn't); the strain on the battery would be far too great.
uiop_on
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December 7th, 2023 11:52
Hi ejn63,
So is the Dell XPS 13 (9315) limited to a maximum charging speed (power) of 20W? I would have thought a modern laptop like this could have charged faster?