It's a brave new world people, The rules we all lived by in the past with Nickel based
batteries do not apply in a Lithium world.
Lithium-ion battery - Wikipedia, the free encyclopedia
" Li-ion cells must never be discharged below a certain voltage to avoid the possibility of irreversible damage. Therefore Li-ion battery systems are generally equipped with a circuit that shuts down the system when the battery is discharged below the predefined threshold. "
I really didn't want to get into a battery history debate but Ill keep it short.
Nickel Cadmium: Has Memory, must be fully discharged, or cycled regularly.
Nickel Hydride: No Memory, can be topped off, and/or cycled at will.
Lithium : No Memory, sensitive to heat, cannot be cycled, and degrades over time whether used or not.