Will DC to DC Converter Protect Tow Vehicle Alternator With Lithium Batteries

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Question:

I have reply to my message, all good info but application is off I have a 24 highland ridge, open range 25th, toy hauler It came with a 200 watt solar system with a go power controller, GO-SB-pwm 30-BT My question was I want to install 2 lithium batteries 100 ah each, I think I need a DC TO DC CONTROLLER TO PROTECT MY TOw VEHICLEs ALTERNATOR IVE READ WITH THE go power controller I have you can charge the 2 lithium lifepo4 100ah batteries as long as hooked up in parallel? Yes? Also looking for a charger to use to charge batteries if they get low, your neco charger look like possible? Will this work? Is there a beater way and what would you recommend? Sorry for the mixup

asked by: Paul C

Expert Reply:

Hello again Paul; I read that as you wanted to install the batteries and the solar, not that you already had the solar installed, so sorry about that. A DC/DC converter will certainly protect the alternator but whether or not it is necessary is debatable. There are a lot of people towing with lithium batteries that don't have this on their trailer/vehicle and don't experience a problem.

With the solar keeping you topped up it is even less of an issue unless you're boondocking and draining the batteries all the way. If you want to be safe you can add a DC to DC battery charger like the # RED96FR which will keep the batteries from pulling too much power. It connects directly to the vehicle's start battery which will allow for actual charging and not just a maintenance charge. You will also need the # RED76FR and # 331-SBI12-LLD for installation.

Also yes, parallel is how you want to wire it. I went ahead and added a diagram below which shows series and parallel. Wiring it this way keeps you at 12V with a 200Ah capacity. Your Go Power solar controller won't have a problem with the batteries like this, just make sure you change the battery type to lithium on the controller. Do not wire the batteries in series or you will turn it into a 24V system which will be bad.

You can use a charger like the NOCO Genius Smart Battery Charger # 329-GENIUS5 with the lithium batteries. This is a great option if you want a back up for charging. However, between the solar, Redarc battery charger, and shore power charging them it will probably never be used.

expert reply by: Robin H

Series and Parallel Wiring
(click to enlarge)

Paul C.

10/21/2024

Do I need a shunt? Also I have a 2016 GMC HD2500 diesel, young weight is about 1000 lbs,, looking for air bags to level truck when towing, any recommendations? Thanks for your help, I’ll be adding these to cart

Robin H.

10/21/2024

@PaulC you do not need a shunt. It will run directly to the battery and then connect to an ignition source on the vehicle side. I went ahead and added the fuse and smart load disconnect you will need for installation in the answer above. The product page has a wiring diagram for lithium and the complete instructions are attached at the bottom of this page so I would look those over as well. For air bags I would get the Firestone Ride-Rite Air Helper Springs # F2613. These are going to be the most durable and reliable option. I also recommend adding an air compressor like the # AL25592 so you can adjust the air bags no matter where you go. This is a pretty basic compressor but it will get the job done. If you want something a little nicer with wireless capabilities check out the # AL58WQ.