Dual battery setup (battery suggestion) (3 Viewers)

Oct 1, 2019
Apologies if this has been covered. I couldn't find much in the search or Google. A little explanation of the end goal to hopefully get some educated suggestions on the recommended battery type for my needs...I have zero expertise in anything electrical.

Replacing an old interstate battery in my Tacoma. The end result is going to be a dual battery setup with Blue Sea ML-ACR holding the charing. After that, adding renogy flexible solar 175w on the roof and their MPPT to feed solar to the house battery (RTT lighting and accessories at camp). The MPPT will eventually trickle back to the starting battery and keep both topped off while sitting in the driveway (not my daily driver)

Am going to get 2 new matching batteries to start this off. Not really a red top fan, but have had yellow tops that worked great for a daily driver.

Has anybody had experience yet with Full Throttle Batteries? OGE sells them and swears by them for offroad/expedition type vehicles and dual batt setups , but I can't find any reviews on them otherwise.

Need something that can be drained pretty low and take a good charge over and over. As well as will take a good constant top-off via solar down the road.

Yellow top, interstate, red top, full throttle, Northstar? Anybody partial to one for a similar type setup?


Jan 9, 2005
Northern Nevada
Not familiar with Full Throttle but specs appear similar to Odyssey & Lifeline. I've been using Odyssey batteries in my UZJ100 for 14-years and typically getting 10-years out of them. Had Lifeline batteries in my then Kimberley Kamper; worked as advertised. Better selection of sizes with Odyssey though. Deka is similar to Odyssey & Lifeline but lower cost.

Use Interstate FLA from Costco in my HD2500 and at $80 its big bang for the buck but wouldn't want them for the rough and tumble world the UZJ100 sees (venting, sloshing battery acid, etc.). Couldn't give me an Optima of any color since they sold out...


Jan 31, 2016
Mind if I ask the reason for 1 of each? Which do you like for the aux battery?
Northstar didn't have the right size battery I needed for my auxiliary. I have Northstar (group 31) for main and Odyssey (1230) for auxiliary.

On the Tacomaworld forums, people are raving about the Northstar 31 so that was the main reason I went with that over teh Odyssey which I know plenty of people are happy with.
May 23, 2019
WNY For Now
Jumping on here as I'm choosing batteries as well:

Any reason why both batteries should be the same? Can I run AGM for the house and lead acid for the main? Will that effect charging in some way? Will the alternator be alright charging 2 different styles of batteries?

I have a upgraded 120A alternator and a solar set-up will charge the house battery when parked.
Jan 11, 2019
Putting in some info that might help you guys. For choosing a charge controller, you have to oversize by 56%, so your solar array is rated for 10A, you will need a charge controlled that can handle 15.6 amps. (multiply by 1.56).

As far as batteries go, you are only supposed to draw them down to 50% capacity as further depletion will shorter their life. You can find a spec sheet which tells you the capacity % at certain conditions and voltage. So if you have a 100 amp hour battery you can only have useful 50 amp hours. AGM and lead acid are both lead acid batteries, the construction just differs and AGM is typically sealed which usually means less losses, and it will last longer. Any "deep cycle" battery for your axillary will do. While you might have an AGM and a regular lead acid battery, the alternator on your car will still try to charge them the same, it doesn't know the difference and will induce the same voltages and currents on both. That being said, the AGM battery might not be charged in the most optimal condition, but I don't think it's anything that you are going notice.

In my truck I have a size 27 regular led acid die hard and a size 31m deep cycle sealed die hard. Any reputable brand will have good performance, such as odyssey, NorthStar, optima. Get whatever has the best warranty and you can get a good deal on.

What do you mean by this:
The MPPT will eventually trickle back to the starting battery and keep both topped off while sitting in the driveway (not my daily driver)


Supporting Vendor
Mar 5, 2021
Tacoma, WA
We have a great relationship with OffGridEngineering, and Full Throttle, great products and we are using them in our REDARC work trucks. As a dual battery setup, I biasedly would recommend a BCDC charger if the AUX battery is going under the hood.

The BCDC is able to control battery charging stages, and profile for varying battery types although like you said it's recommended to keep them the same. You will also be able to ditch the solar regulator as it's built in, along with a battery isolator to keep it from tapping into that start battery.

extremely easy install, check out this video from one of our friends at Trail Benders Overland in CA!

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