Adding Extra Battery Power to FFE

Anti_Climax · Oct 23, 2024

So, you'll want to tap the output that will be powering the vehicle contactor and run that to another small relay. Then use that relay to switch your additional contactors with a new fused 12V circuit.

Chances are good that the relay will not handle driving 2x the normal load, but a small relay should be a marginal increase over the stock contactor load.

Let me know if you need/want a diagram

TheChickenTendy · Oct 23, 2024

If you could draw up what you are talking about that would be greatly appreciated.

Anti_Climax · Oct 24, 2024

TheChickenTendy said:
If you could draw up what you are talking about that would be greatly appreciated.

triangles · Oct 28, 2024

TheChickenTendy said:
How much power does the Focus motor draw? What discharge rating should I be looking for with an external pack? Also any leads on where I can get Li-ion packs? I can only find LiFePO4 packs in large sizes.

batteryhookup.com has an assortment of new, used, and salvage batteries.

TheChickenTendy · Wednesday at 8:35 AM

So Motorscm1 is correct that the car doesn't seem to care about an extra battery being plugged in when driving. I took a 20 mile drive and the budget went down but the status kept going up. Unfortunately the car refuses to charge the extra pack. When I plug the charger in the light ring does its normal thing and then it flashes a few times and turns off. I guess I'll have to rig a separate charger to the extra pack.

Anti_Climax · 2024-11-22T17:37:15-0600

TheChickenTendy said:
So Motorscm1 is correct that the car doesn't seem to care about an extra battery being plugged in when driving. I took a 20 mile drive and the budget went down but the status kept going up. Unfortunately the car refuses to charge the extra pack. When I plug the charger in the light ring does its normal thing and then it flashes a few times and turns off. I guess I'll have to rig a separate charger to the extra pack.

Is the extra battery off the bus before charging starts? Part of the charging process involves checking for voltage with the contactors open and closed. If it's present before the contactors trigger, it's seen as a fault.