I just want to say thanks for all the comments. I'm not trying to advocate
anything, and I really appreciate the feedback and discussion.

On Thu, Mar 13, 2008 at 11:16 AM, damon henry <[EMAIL PROTECTED]>
wrote:

>  This will work, and probably work fairly well, but is a lot of work, and
> will take a loooong time to charge.  One thing you need to keep in mind is
> that when you put two batteries in parrallel their capacity becomes the sum
> of the two batteries, so if you put 6 12 volt batteries in parallel and they
> each have 50 ahrs of capacity you now have one 12 volt 300 ahr battery.  If
> you have a battery charger that can dish out 300 amps you can charge in
> about one hour, 30 amps ~10 hours, 10 amps ~ 30 hours.  Also remember that
> each of your Anderson connectors will be seeing full discharge current, and
> will need to be rated appropriately.  If you use the smaller connectors they
> will melt.
>
> damon
>

A 50 ah battery only has about 25-30 usable ah in an EV, so even with a 12v
40 amp smart charger (that cost $85) it would only take about 4.5 hours. I
have 35ah battereis, so I could charge in about 2.5 hours.

I think I sized the Anderson connectors appropriately---as large as I could
possibly fit. I plan to use an SB350 where it permits, and use PP180s for
the rest. BTW, I found a company that mostly carries just Anderson
connectors that was prompt to ship my order with good prices:
http://www.powerwerx.com

I guess I should clarify what my reasons for doing this are:

1. One charger will be less likely to fail than any one of 6. Sure I could
buy tens of chargers to replace continually failing chargers over a period
of years, and have the hassle monitoring the ones that die. But I'm tired of
fixing stuff. I want to do it right, and be done with it.

2. Parallel charging is simpler than any outher sound charging method,
except one: using one 12v charger and manually connecting it to each
battery, one at a time. Please not the word *sound* in the last sentence.
String charging just isn't sound in my opion without adding a load of
complexity to make it sound.

3. There are some really neat advantages to being able to wire the pack in
parallel. For instance, I can charge from any car alternator w/jumper cables
in an emergency.  I can run a 120v AC inverter with my bike, to even charge
another EV if need be. I can also charge really slowly overnight to slightly
improve the life of the batteries by selecting the 10/25 amp rate. Can keep
a small low-voltage emergency charge Nimh/lithium ion pack on board to
charge the batteries and get an extra 1-2 miles range in case of running out
of charge.

4. When I switch to LiFePo4, I'll be able to charge all of the batteries in
a more uniform manner.

5. Everyone is saying no, and to my knowledge it hasn't been done. I want to
prove them wrong, even if I am wrong.

6. An EV project is a fun experement. Why not use it as a platform to try
new things? If I wanted something that has been proven and is known to work,
I would drive 5 miles to my local motorcycle dealer.

7. I'm not using the No.6 as an excuse to try something stupid. I've put
much thought into this, and am about 95% sure it'll work like a charm
despite the negativity.

Regards,
Andrew in NM

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