Aux. Battery/charging/set-Up

[ParadiseMJ]

I'm wanting to set up an auxillary battery, easily removable to charge, and keep charged for a trolling motor battery.  Wondering if anyone has an idea how to do this...or HAS done it.

 

How would the wiring be set up? Off the batt cables or directly to alt?  Would I have "backfeed" issues? Would I need another (bigger) alternator?  Could I keep it in a tool box or camper...or is there a spot under the hood etc.?

 

P.S. Thanks Don.

[88mjgilley]

a 4 gage wire from the battery to the secondary would work fine,and then just ground it as close as you can to the frame. For charging purposes i normally use a snow plow solenoid hooked into the ingintion. So the battery only receives power when the engine is running. I would mount it in a tool box. Your stock alternator should do perfectly fine charging a second one seems how it won't be doing that big of a draw

[HOrnbrod]

P.S. Thanks Don.

Welcome.  :cheers:

 

a 4 gage wire from the battery to the secondary would work fine,and then just ground it as close as you can to the frame. For charging purposes i normally use a snow plow solenoid hooked into the ingintion. So the battery only receives power when the engine is running. I would mount it in a tool box. Your stock alternator should do perfectly fine charging a second one seems how it won't be doing that big of a draw.

 

Yes, this setup should work fine using an ignition switched solenoid so the second battery only receives charging amps from the alt when the engine is started and running. However, if the second battery is nearly discharged nearly ALL the charging amps from the alt will go initially to the weakest battery until they equalize. So just make sure the deep cycle trolling motor battery isn't completely dead. A solar trickle charger wired in parallel to the second battery would help prevent this.

[jpdriver1]

here's what I'm gonna use

[danbyrambler]

Solenoid should be continuous duty - - - I've used 12v Golf Cart relays for years - typical 200-300 amp contacts - $10-$15

:wrench:

[ParadiseMJ]

Well, that's a LOT simpler than I had thought...Thanks gents.

[jpdriver1]

good point paradisemj

[Bornindesert]

Took a pic of this set-up and custom fabricated air intake. Notice the windshield bottle is missing, but look at the room it free'd up on the driver side. Enough for a second full size battery provided you made your own tray. Not saying this is how I'd go, just tossing out some ideas for you.

 

I posted a similar thread a few weeks ago, got some good ideas from the CC experts.

[HOrnbrod]

Better to move the washer tank into the left inner fender by using the 1997 and up tank. Frees up a lot of space.

 

Also that custom air intake looks like it's sucking hotter engine bay air than the stock air box to me.

[Bornindesert]

Pretty much agree with hotter air thinking on that custom intake location. Plus, you lose the access to the clean air coming in through the grill. It would be interesting to thermocouple the two locations and get some real time temps.