aux battery pros and cons...

[ebg18t]

I ran the diehard platinum in my last truck. Excellent battery

I am currently running dual Duracell AGM's (made by East Penn/Deka). $125 each from SAMs club. Have worked out great so far.

 

[pluton]

There is always the simple option of carrying the 2nd battery and charging it with solar. No need to hook up a complex dual system. If your starting battery should ever fail you can either swap them or jump with the aux. KISS
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Dual battery systems no longer need to be complex--IF you are willing put your faith in modern electronics and microprocessors.
The simplest is to connect a second battery in parallel with the main battery. Of course, if you stay camped out long enough without running the motor to charge, you still run the risk of draining the starting battery.
The next simplest---what I did---is buy an automatic 2nd battery manager system*. The only connections are a pair of heavy cables running to the main battery in the engine compartment.
The auto system senses when the vehicle is starting, cruising, and stopped and connects and disconnects the aux battery as needed. You can even elect to join/disconnect the two batteries for winching, etc, at the push of a button.
I've had it about 7 months, with about 16-20 days of active service in the field. So far, it has worked flawlessly. Will it still be working fine 5 years, 10 years from now? I don't know. Some folks "don't trust" automatic battery managing devices.
* National Luna Portable Power Pack, about $558. Die Hard Platinum battery to put in it: about $220. Less if it's on sale. That's it. Comes with necessary cables. Additional wired remote(nice) for another $90 or so.
It's even cheaper if you buy the battery manager by itself, but I knew I'd be changing vehicles in the near future, so wanted to avoid a vehicle-specific, permanent installation.
For a very long term stay somewhere, a solar charger would be an excellent addition. Seems like you'd have to have an awful lot of sun and an awfully large solar panel to keep a car-sized battery charged.

 

[pluton]

This is a really interesting product - might be the answer to the whole dual battery situation - and EE has a good write up on batter usage in general.

http://www.expeditionexchange.com/antigravity/

I like John at EE, and have bought several things from him, and I like that super-jumpstart thingy, but his write up on it implies that you can drain your vehicle's battery flat with abandon and it won't matter 'cause you have this super-jumpstart thingy. Of course, WE all know that that would be unwise.

 

[HenryJ]

That Antigravity XP-1 really looks like an awesome little pack to keep in the pocket of my 100W solar panel case. Right size and offers all the adapters to power what ever I might want to.

 

[bat]

I already have a diehard platinum and 100 watt solar setup but tossing the idea around of a small Odyssey pc680 as backup. At 14lbs and small enough to go anywhere in the engine bay and with enough power to start my Tacoma. It would be only be for starting if my main battery died and would be setup with an isolator.

 

[Mrknowitall]

I would probably go with a dedicated "house battery" as well- it will also make your main battery last longer. If you want CHEAP insurance that the truck will start the next morning, you can always just carry a jump-box.

 

[BurbanAZ]

I always like having an aux batter just for peace of kind. We went on a trip once in bad snow and mud and kept getting stuck and had to winch out trying to get back home. After a little while it ruined my battery and alternator and we're barely able to limp down the back of the mountain before the truck completely died. That night there was a really and snow storm too so we would have been stuck for probably a few days if we weren't able to get back down. We had to do the drive back at night in the snow with no headlights and the gauges all stopped working and them tranny stopped shifting as the voltage dropped the rest of the way down. After that trip I always want to have an aux battery if I'm going to have a winch, lights, inverter, ect...

 

[cc tacoma]

I got a dual battery set up about a year ago from Adventure Trailers. It's an IBS (Intelligent Battery Systems) with a rogue engineering low voltage disconnect (kinda redundant) and I love it. I run a National Luna split weekender fridge/freezer, some LED lights and multiple 12v outlets for charging phones etc... They put in a group 27 AGM battery with it. So far after a year I've had zero issues. During regular conditions I can camp out with the fridge running and turning on lights and charging my electronics for about 48 hours without having to start the truck to re-charge the "house battery".

The beauty of the system is that I never have to worry about leaving anything on or turning off a master switch when I leave the truck. The system links the truck and house batteries together automatically to charge both off of the alternator while running the engine. Then it automatically separates the 2 batteries when you turn the vehicle off. Unless you want to manually link them together (for 30 or 90 minutes I think, it's your choice) to skim a little juice off the top of the truck battery since sometimes they can be overcharged when they never really get used, and then it automatically separates them again so the truck battery is safe from depletion. It also gives audible alarms when either battery reaches almost unhealthy levels and it also will shut down power when either battery gets to actual unhealthy low levels.

And last but certainly not least, you can manually link the 2 batteries in case you need (for some crazy reason) to jumpstart yourself with the push of a button, and get back on the road!!!! :wings:

The next step for me will be to link in a solar controller and a panel so that I can go longer than a couple of days without starting the rig.

Anyway, here are a couple of photo's and I hope this info helps. Any questions let me know, but if it's a super technical question I would definitely give Adventure Trailers a call. They are the best!!!

 

[cr500taco]

Do you need a higher output alternator for a dual battery setup or is the stock size alternator sufficient?

 

[montypower]

You may consider something simple like a single large battery vs dual batteries. My experience with the Odyssey 1400 wasn't great. My ARB fridge would kill the battery after only 10-12 hours. The battery just doesn't have the reserve capacity required... Switched to the Die Hard 31M. It will run the fridge for 3+ Days without running the truck and it has no issues starting. I carry a decently HD jump box for my backup. Simple, less money, works great. Plus, the jump box has proven beneficial for helping others with dead batteries.

Dual batteries have their place but realistically don't make sense for most people. Just my thoughts...

 

[cc tacoma]

Do you need a higher output alternator for a dual battery setup or is the stock size alternator sufficient?

I have heard of certain stock alternator's being unable to keep up with the demands of a dual battery set up. However, so far with my stock Tacoma alternator it has been sufficient to supply the system with no problems. If I notice any issues or changes I'll keep you posted.


Sent from my iPhone using Tapatalk

 

[1911]

I've had dual batteries in my FJC for years, running a fridge, ham radios, GPS, etc. and the stock alternator does fine. Now on my FJ40, it really benefitted from an alternator upgrade, but the stock one was only 45 or 55 amps. Modern trucks have pretty big alternators to start with.

 

[Milo902]

I ended up getting one of those antigravity jump start packs featured on the home page a few months ago, with the idea of upgrading my stock battery to a slightly larger single when it dies. I figure the larger single battery will have excess capacity for a future fridge, and the jump start pack can easily be transferred from vehicle to vehicle as needed. For me that is a big plus as I usually have multiple vehicles, and find myself road tripping/camping as a passenger often as well.

Just got the jump starter today so I can't give any feedback other than it's tiny. Unfortunately I probably won't get to test it until I really need it, hopefully it delivers as promised.

 

[cr500taco]

cool, thanks 1911. I guess that I could do the trial and error, process.

 

[cr500taco]

I ended up getting one of those antigravity jump start packs featured on the home page a few months ago, with the idea of upgrading my stock battery to a slightly larger single when it dies. I figure the larger single battery will have excess capacity for a future fridge, and the jump start pack can easily be transferred from vehicle to vehicle as needed. For me that is a big plus as I usually have multiple vehicles, and find myself road tripping/camping as a passenger often as well.

Just got the jump starter today so I can't give any feedback other than it's tiny. Unfortunately I probably won't get to test it until I really need it, hopefully it delivers as promised.

I have heard that the Tacoma's stock output is ~75 amps.