Can I remove the battery prior to a full charge? I consistently have maybe 5/10 minutes of trimming left.

Absolutely. The Ego battery/charger system hits about an 80% charge in about 1/2 to 2/3 the full charge time, making it extremely useful for those people who need just a little more capacity than the battery can deliver. Go ahead and pop the battery back in he charger, take a short break, then finish off.

Something most people don't know about charging a battery is the longest part is putting a top charge on. Your battery is at 95% faster than you think. If EGO did as most engineers do, once you reach a certain voltage, the charge rate is greatly reduced. To avoid over charging and causing a fire. So around 95%-97% the charging rate drops. This allows for the battery to be cut off once it reaches its fully charged voltage, but also prevents the nasty fires you can get from over charging. So essentially once you hit more than (lets say 92% because I have not actually measured on EGOs device how it charges) then your charging is slowed down.

So you can absolutely pull the battery early, because the last bit of time is spent slowly filling the rest of the tank so as not to over charge, so to speak. 

only charging to 75% - 80% consistently SHOULD greatly enhance its useful life.  Sure, you'd get a little less run-time, but Lithium Ion chemistry lasts almost forever if kept at 3.7V per cell.  

Why EGO did not build a 85% charge and stop button, to elongate the battery life for people who do not want their battery fully charged. (I don't have a EV car, but heard most EVs have this feature, why not EGO charge battery fully when user don't want it to be fully charged)