@Llamagirl...It is my understanding that re-chargable batteries were Nickel based and benefitted from a total discharge. However,nowadays, most batteries are Lithium Ion and a total discharge can damage them.
(Copied and pasted from an Internet article) :- //Old NiMH and NiCd batteries had a “memory effect” and had to be completely discharged from 100% to 0% to keep their capacity. Modern devices use Lithium Ion batteries, which work differently and have no memory effect. In fact, completely discharging a Li-ion battery is bad for it. You should try to perform shallow discharges — discharge the battery to something like 40-70% before recharging it, for example. Try to never let your battery go below 20% except in rare circumstances.//
Hans.