Re: Spitfire Project

[XURQ03A@prodigy.com ( LEE A HART)]

> convert my 1980 Triumph Spitfire to electric...
> The vehicle will be used primarily for autocross competition.
> 26Ah Hawkers... thought about two strings of 156 volt... 560 pounds
> better to go with 42Ah batteries and have only one string... 428 lbs.

For competition, you want the lightest pack practical. People have used the
little 26ah Hawkers for racing very successfully. Will one string give you
enough capacity for a run?

And, you don't want to be carrying the dead weight of an onboard charger or
battery balancing system for racing.

How about this? Bundle the 26ah Hawkers into packs of some manageable weight
and size; say 3 for 36v, 65 lbs. Put an Anderson connector on each pack, so
they are easy to plug in. Build the battery boxes in the car to facilitate
quick removal. Since range = weight, for racing you install a single string
with enough mass to complete the event; 3 packs for 108v, 4 for 144v, 5 for
180v etc. If you bump into the controller's upper voltage limit with one
string, you can use two strings. Another set of packs can be on charge, ready
for the next race.

The easiest charging setup would be a big 36v charger that can charge any
number of packs in parallel (also equalizing them in the process). At most,
you could include 3 Rudman or BatPro regulators to monitor the voltage across
each 12v battery in the pack (all packs being charged at a time could share
the same three regulators).

But for driving on the street, you don't want to mess with changing packs all
the time. Your cost and reliability will be better with a single string.
Figure out how many lbs of lead you need for the desired range, pick a
reasonable voltage (not too low, not too high), and use a battery size so that
one string gives you the desired weight. This is where a system like you
proposed (Zivan NG3, Smoother, or whatever) would make sense.

Lee Hart                     If you would not be forgotten
4209 France Ave. N.          Soon as you are dead and rotten
Robbinsdale, MN 55422 USA    Either write things worth the reading
phone (612) 533-3226         Or do things worthy of the writing
e-mail XURQ03A@prodigy.com   (Ben Franklin, Poor Richard's Almanac)