Lee, A small micro was my first thought however the bq2003 doesn't seem to have any way of regulating voltage, just current. Switching to the bq2031 gets me voltage regulation as well as current. I think Nawaz mentioned an algorithm where you held constant current to a specific voltage and then continued at c/20 or c/30 until the voltage increased less that .004v / cell / hour. Now that I might be able to do. Any thoughts on that?
thanks, Steve In a message dated 10/8/2002 2:55:04 PM Eastern Standard Time, Lee Hart <[EMAIL PROTECTED]> writes: >[EMAIL PROTECTED] wrote: >> The way the bq2003 is used in the Tropica charger (oh I'm out on a >> limb here) is as a controller for a buck converter... My problem is >> that it looks to me like in this configuration, it just keeps pumping >> out 12 amps until a threshold voltage and then shuts off. This doesn't >> sound like a valid charging method for lead acid. > >No; it is a poor algorithm. > >However, if it is built well enough, it could serve as the power stage >for a smarter charger. A small microcontroller could implement something >like a dv/dt algorithm: Full current until voltage hits 2.4v/cell, then >constant voltage until current falls to 5 amps, then (if you want to >equalize) constant 5 amps until voltage stops rising or reaches >2.5v/cell. >-- >Lee A. Hart � � � � � � � �Ring the bells that still can ring >814 8th Ave. N. � � � � � �Forget your perfect offering >Sartell, MN 56377 USA � � �There is a crack in everything >leeahart_at_earthlink.net �That's how the light gets in - Leonard Cohen > >
