Given that the system is on the order of three years old, it's more likely the battery has been declining due to normal aging and passed the critical threshold that tripped the warning. Open a command prompt with administrator privilege -- then type powercfg /batteryreport This will report the design and current charge capacity of the battery.  It it's down to less than 50% of its design capacity, it's time for a new battery.  
Hi, we have a user running a Dell XPS 15 9575 without a single issue until today.  Dell Power Manager said battery health was fine...  then I ran all available Windows Updates as i do on all our Dells, then SupportAssist until none remained.  15 minutes later the laptop shut off and when restarted it says "Your battery can long longer provide sufficient power".  I checked Dell Power Manager and now it says one bar of health, battery health is 'Poor'.  Coincidence? Probably not... I suspect the updates from Dell are the problem, not the battery which is genuine and has never had a problem.  It is connected to power too, not running off the battery.    I see other people have posted the same issue and the 'community accepted solution' is to disable "Power plans and Battery" in the Dell Feature Enhancement Pack via the Control Panel.  Similar to others, I cannot find that option.... [URL] What do i have to turn off, disable, uninstall to stop these erroneous messages?  Thanks ps. I should note that I did the updates over the course of a day or two.  There were no problems until after the very last update i installed which was the recent BIOS update.  After that was when the issue happened.  
Installed updates, now battery health is "Poor" "Your battery can long longer 
provide sufficient power"