I have a 15 IZIP E3 Dash, has around 220 miles on it. During a full charge it always read 45 miles max range. I just took my 1st long ride took the battery level to zero.

Upon charging it back to full it now read 40 miles max range. Could I have damaged the battery by running it to zero power? I can't see why max would go from 45 to 40 miles for no reason.