Re: Is it true that a cellular phone battery should be discharged?

There are three kinds of batteries that one might expect to encounter in 
cell phones : Nickle Cadmium (NiCd), Lithium Ion (LiON), and Nickle Metal 
Hydride (NiMH).  Newer phones use LiON.

Of the three, only NiCds require a periodic discharge.  NiCads have an 
unwanted memory feature.  NiCads remember their discharge cycles and if you 
don't fully discharge them from time to time, they will not supply power to 
their rated level.

See http://batteriesdirect.com/ for 
more info.