That's the trouble with more guages, more things to worry about, it may not be accurate if it is showing up to 14 volts off charge. Provided you are not lossing battery fluid it should be ok. Charging voltages tend to be a bit higher these days anyway.
When your engine isn't running the battery should show around 12v. When your engine is running, the alternator is constantly recharging the battery at 16v.
16 volts is too high - your battery will be getting cooked - plates will buckle with the excess current. charging voltage should be between 13.5 and 15