Electrified Firebus

Andrew is putting some final touches on the van’s electrical today. We are working towards being able to charge an auxiliary battery while we drive. This spare batteries can power the water and fridge in the back when we need it, without draining our main battery. It has been quite the process of trying to figure out how all this electrical components work together, like fuses and isolators, and where exactly you can purchase these things, but I think Andrew has done a great job of getting it all sorted out.

We have wired the main battery up today to be able to drag power from it when it’s being charged as we drive. To give you an idea, this is what it all looks like.

This is our main battery. The auxiliaries we have (not pictured) are two deep-cycle batteries we have on loan from a friend.

We need a cable running from the positive end of the main battery, with an in-line fuse to protect the system in case it short circuits. This is the in-line fuse and 4 gauge wire.

This is how the in-line fuse looks after one side is installed.

Now we are able to run that cable from the postive node on the main battery, and send it through a hole the body, to just below the steering wheel. We don’t need another black wire (ground) because the main battery is already grounded.

From here, we can connect the red wire to the battery isolator/charging relay so we can manage when the power gets switched from charging the main battery, to the auxiliary. We only want it to charge the second one when there is enough juice for the main battery.

Andrew can then install the charging relay and ensure it is grounded by attaching it to the chassis (the best way to ground batteries on a vehicle).

Which looks like this when it’s completed. The second red wire (on the right) runs all the way to the auxiliary batteries, which are also grounded to the chassis.

Hopefully this gives you a bit of a taste of the what we’re up to. We’re not totally done yet, but when we are it will be great to be able to have a bit of extra power whenever we need it.