[brucepick]

Daox,
Sorry, no pics yet. Car actually looks pretty messy inside; parts and tools all over the place. I have a circuit diagram but haven't made it into a .jpg yet for posting on photobucket. See below though, for notes on the circuit design.


oil pan 4,

I recognize your post re. charging was mainly re. California98Civic's battery issues. So I'll just say that in my setup the alt doesn't ever charge the lithium, but could be used to charge the lead acid starter battery and also power the whole car if needed on occasion.

There are two circuits, I need to state this clearly. One circuit is the regular battery up front; hooked up ONLY to the starter full time. Later the front battery will have a + cable going to the alt via an under-hood switch. The other circuit is the Lithium pack, wired to the main fuse box from where it powers the entire car, except of course the starter.

The alternator + cable is currently DISCONNECTED and in any case, I don't plan to use it to charge the lithium pack except possibly in some unexpected emergency situation. It can still charge the oem starter battery if needed.

There is a JUMPER from the front battery to the main + wire from the lithium pack (and thus also to the main fuse box), with a switch in the jumper line. After disconnecting the lithium's ground, the jumper can serve either of two purposes when the jumper switch is closed: (1) to power the main fuse box [and computer and MPGuino etc.] during lithium charging, and (2) to power the main fuse box from the main battery + alternator if I should need it, such as for a very long drive.

California98Civic,
A multi-charger system like you discussed here looks like a really good idea, but it has to be very well thought out.

If you develop it, I believe you'll need to know exactly the charging as well as discharging "needs" of each battery type you are using. Then you'll be able to (possibly) provide the environment they need. I've tried to keep this aspect of my setup relatively simple by 1) charging the lead-acid only from a plug-in charger built for lead acid batteries, and optionally off the alt, which is designed to support the lead acid pack. And 2) charging the lithium pack only from it's dedicated charger, which is set up for lithium packs of that size and voltage. Ultimately I hope to replace the front lead acid with a deep cycle lead acid, which will be able to power the headlights for a good while. But that's still a lead acid pack so can be charged by the same hardware I have now.