knoen

My Feedback: (1)

Hi
I have plans to connect a extra 12V car battery in the bagage compartment in my car. I want to connect the battery so it is always charged when I use car daily. Any tips how to do this?
Links? Wire schematics?

nascarfan88

Knoen,

Generally you could use what is called a battery isolator. What it does is keeps the batteries charged by switching back and forth between the two. The battery with the lowest voltage gets the charge. I've always seen them in marine use around here but camping outlets should have them as well. I'm sure somebody else can shed a little more light and provide a circuit diagram to do it yourself. Might look around at Alan's R/C links web site.

Good Luck

Mike

chris100

You might want to check up on some car audio websites. www.termpro.com is a good one. These guys run multiple batteries in their cars all the time.

jettstarblue

Mount your battery, hook up HEAVY CABLE (WIRE) with a parallel circut (sp), like you would hook up jumper cables.

Jetts

iflyrc24

My Feedback: (5)

I set up our service truck with 4 large truck batteries that we use to jump start big trucks with.

I used a 100 amp accessory relay to keep the 4 batteries charged. Hook a 10ga wire from the batt post on the alternator to one of the big posts on the relay. Hook the other big post of the relay to the pos side of your aux battery. Ground the aux battery to the frame. Hook a 14ga ignition power wire to the pick side of the accessory relay. If it has two little posts ground the other one.

I used 1/0ga heavy cables and a 100 amp relay on my setup because I wanted the full power out of the alternator to the batteries for jump starting. You could use a 30 to 50 amp relay for yours.

That's all there is to it. The aux battery will charge while the engine is running and not run your starting battery dead if you kill it charging the plane. Make sure you use a continuous duty rated relay or it will burn up the coil.

DEG