Forum Discussion

pinesman's avatar
pinesman
Explorer
Jul 04, 2019

charging batteries with truck

Several years ago when the fifth wheel that I had at the time only had room for one battery, I carried 2 more in the back of my truck. I used 2 sets of good jumper cables with ring terminals on one end and winch connectors on the other end to supply extra battery power when dry camping. Fast forward a few years and my current trailer has room for 4 batteries so I do not use the cables like I used to. However, I got to thinking about using those same cables to charge my batteries using the truck. I would not be using it for hours to run everything
but just a little while to top off the batteries in the trailer. Has anyone done anything like this?
  • Artum_Snowbird's avatar
    Artum_Snowbird
    Explorer
    Jul 04, 2019
    It can certainly be done. Use good jumper cables right off your truck battery to the trailer batteries.

    The however in this case is your truck engine is producing a substantial amount of power just to run it's engine. A 2K generator will produce much less power and it's easier of fuel to run. The battery pack will take a charge at the same rate from both. One engine uses a lot more fuel than the other.
  • BFL13's avatar
    BFL13
    Explorer II
    Jul 04, 2019
    Seen it often where folks use jumper cables from truck battery to trailer battery for a quick recharge. Theory is the jumper cables are shorter and fatter than the long skinny wires back to the 7-pin.

    Neither method gives you much of a recharge, but it can keep you going. Better to have a small generator and use your converter for a higher amp, faster recharge. Solar can sometimes help too.

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