I have a factory-stock 11th gen I7 still on 3.07 bios running Linux Mint. Forgot to bring my stock charger on a trip so was forced to try other options – which in my case were several different 5v 30w cell phone chargers and a 12v 45w Chromebook charger.
As discussed elsewhere (including here) the laptop charge controller will accept anything from 5-20v 15w to over 60w. My stock charger is 60w @20v.
All chargers “worked” in the sense that the charge LED came on solid and the laptop continued to run with them. But the only one that was practically useful for more than a few hours was the 45w Chromebook charger – and that still acted a bit weird.
It appears that my laptop uses around 45w in normal operation. Any of the 30w chargers would supply power but the laptop would never really recharge the battery with them. So essentially they just extended battery life by relieving the battery of about 30w of load when in use. With these chargers the battery icon would never indicate “charging.”
The 45w Chromebook charger would allow me to use the laptop as much as I needed (at least several hours at a time). During use the battery icon would switch randomly between “charging” and randomly displaying a wide range of remaining time – anywhere from a few minutes to hundreds of hours.
Once the controller was in the “battery critical” mode it was stuck there. Unplugging the charger would cause the laptop to shutdown within a minute or so max; often sooner. Generally this behavior was confusing at first but eventually seemed make sense, or at least to be predictable.
Most of the above seems to me to be normal and expected behavior when running on a 3rd-party charger and a dead battery. What did not seem normal though was the behavior when the charger was plugged in while the laptop was either off or hibernating.
Then I would have expected the charger to (perhaps slowly) recharge the battery to full charge, thus allowing me to use the laptop to run on battery only for at least some reasonable period of time. But this was never the case.
Even though it appeared that the battery was actually being charged, the controller did not seem to know this – it remained stuck in “battery critical” state.
Once I returned home and plugged the stock charger back in, the battery icon fairly quickly (within a few minutes) returned to “full charge” state and all was back to normal. So it was pretty clear to me that the battery really did get charged even though the controller remained stuck in battery critical state. Perhaps the FW tech team understands why and if so, please share.
But in any case, if you find yourself without the stock charger and need some guidance as to how to choose the best replacement I believe these should be your guides:
- At least 15v, preferably 20v, but not more than 20v.
- At bare minimum 45w, preferably 60w. More than 60w should still be safe.
Best solution: don’t leave your stock charger at home! 
