Charge AGM Battery with Tow Vehicle

[RunnerDuck]

I'm just finishing up the build of my teardrop and now in the 11th hour I have an electrical question.

I have a portable solar panel I can connect to my AGM solar battery to use when boon-docked. I have a trickle charger that will maintain an AGM battery when I'm plugged into 120V shore power to keep it topped off. And I have my F250 hooked up to the battery through the seven pin connector so it will charge as I drive.

Someone mentioned to me that it can be hard on the truck or truck battery or the AGM battery if both the truck battery and the trailer battery are not the same. The truck battery is a lead/acid battery.

Can someone shed a little light on this before I fry something?

Thank you,

[MtnDon]

An AGM battery is a lead acid battery. It is constructed differently but is still a lead acid battery. The charge parameters on most AGM are the same or close enough as a standard maintenance free auto/truck battery. The truck and trailer will likely have different capacities; amp-hours. That is where the potential issues may stem from.

I have towed a variety of trailers and had a couple Class C RV's that had the truck/RV engine charging system also charging the trailer or coach batteries. Since learning about how to maintain batteries properly some 40 years ago I have never had a battery failure that could be blamed on a connection as you described. In other words I have had no premature battery failures and I tend to keep vehicles 8 to 10 years or longer. Mainly I believe there may be a theoretical potential problem, but IMO, it is more theory than practical. Go enjoy yourself and your trailer.

[H.A.]

er.

[RunnerDuck]

Thank you for the great replies, I'm feeling better.

One other question that came up is, what about venting. I've read that AMG batteries do not need to be vented but then someone else said that they do. Since they are fully sealed I'd think that they should be good. Mine is in the tongue box so it's not in the cabin.

Thanks again,

[H.A.]

AGMct.

[RunnerDuck]

So H.A. I guess this should work.

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