You have to reset a system file, so the phone has to be rooted. If it is, install
Battery Calibration (Root) and follow the directions.
If not, let the phone run until the phone tells you to charge the battery. (Don't do this very often - normally you should never drop a lithium battery below 40%.) Then plug it in and wait until it gets to 100% - then let it charge for another hour. (It's not at 100% the moment it says it is, the percentage is calculated from the battery voltage - which is higher when the charger is charging it. Once it's charged, charging stops and it's at a real 100% - and with a battery that large and a standard charger, that can take an hour or even more. [The only way to really tell is to watch the battery's voltage - when it stops going up, the battery is fully charged. That takes an app that needs root, or a voltmeter and some very thin wires so you can connect the meter to the battery while it's in the phone being charged.])
That's about the best you can do with an unrooted phone.