[sci.electronics] lead-acid charging from automobile electrical system

faunt@dustbin.cisco.com (Doug Faunt N6TQS 415-688-8269) (08/13/90)

I want to charge and maintain a charge on a gel-cell from an
automotive electrical system.  I think that one way to do this is to
hook up a low-voltage-drop voltage regulator IC in constant-current
mode for the maximum charging current (about 1.6 A in this case).
This will limit the current to the gel-cel to the maximum allowed
bulk-charge current if the gel-cel is deeply discharged, but allow the
gel-cel to be charged at a pretty high rate until it gets pretty full,
and then taper off.  Do some of the battery experts have comments or
pointers to more information about this application?
Mostly this battery will be charged from an AC charger, but I would
like to be able to charge and maintain the charge in an automobile,
also.
thanx, doug
faunt@cisco.com
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	faunt@cisco.com	 415-688-8269