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FJames · 07-26-2011, 01:26 PM

Actually charging lithium-ion batteries is a tricky business that is never left to a "dumb" charging circuit. It's almost always controlled by a smart IC (e.g., like http://www.intersil.com/isl6291/) that uses thermal management and current limiting to control the charge rate.

There are two ways to go:

a) You limit the current draw to 500 ma so that it will charge from any standard USB port or USB charger without overloading it.

b) You supply your own charger with > 500 ma capacity that is intended to be used with the device.

Most devices that don't have huge batteries that would take a long time to charge at 500 ma stick strictly to a).

07-26-2011, 01:26 PM	#27
FJames Addict Posts: 320 Karma: 320941 Join Date: Jun 2011 Location: Canada Device: Kobo Touch & Aura	Actually charging lithium-ion batteries is a tricky business that is never left to a "dumb" charging circuit. It's almost always controlled by a smart IC (e.g., like http://www.intersil.com/isl6291/) that uses thermal management and current limiting to control the charge rate. There are two ways to go: a) You limit the current draw to 500 ma so that it will charge from any standard USB port or USB charger without overloading it. b) You supply your own charger with > 500 ma capacity that is intended to be used with the device. Most devices that don't have huge batteries that would take a long time to charge at 500 ma stick strictly to a).