Hi Utkarsh. I Actually FIXED this problem months back. and I exactly want to help you on this so that you can fix it yourself too..
the problem which is creating your battery to show an exclamatory mark is your power settings.
so follow these steps to get rid of that sign and a perfectly working battery.
1) Click on your battery icon (left click) you should see an option called " More power options" at the bottom of the popup.
click "More power options"
2) Now you will be taken to your control panel where you can see all of your power plans and under each plan, you will see an option called "Change plan settings"
3) Click on "Change plan settings" for your active power plan. Now you will get redirected to another control panel window, where you can see two kind of power options to get adjusted. that is, when you battery is plugged and when your battery is unplugged.
4) Don't touch those options, just click on "Change advanced power settings" at the bottom left of that window. THIS IS THE AREA WHERE WE NEED TO FIX!
5)After you click on "Change advanced power setttings", you will see a POWER options popup, go to the bottom and then you can see something called "Battery" with a plus sign on the left. click it.
6) Now you just have to change the levels for the following values
--> Critical battery level ( you can change it to 10%)
---> Low battery level ( you can change it to 20%)
Now once that's done, YOU WILL NO LONGER SEE THE EXCLAMATORY MARK ON YOUR BATTERY!!!!
So I hope this works!
Reply me back when you've succeeded fixing it.