|MadSci Network: Engineering|
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.
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