[SpyKiller112]

What is the best way to take care of your battery? Should you charge the battery fully and then let it fully deplete? Or is it better to charge when there is still some juice left?

[ChuckE]

To fully deplete and then recharge, is called "deep-cycling"
I have a Blackberry "Pearl" and its battery is LiIon (Lithium Ion). I would think yours is also.

The old rechargeable batteries, like the NiCads (Nickel Cadmium), could sometimes be rejuvenated by deep-cycling the battery. Today's better LiIon batteries do not have the sort of problem that would be helped by doing that.

Generally think of the LiIon batteries as having about 200 charge cycles in it. So I would not bother deep-cycling, nor even trying to keep "topping off" the battery charge.

Just re-charge the battery when your battery level starts getting a bit lower than what you are comfortable with.