Plugging AC battery charger into my inverter. Good idea or not?

[Walrus]

I'll get right to the point: I'm departing on a month long trip soon, and will need a way to recharge my deep cycle. Would it work to bring my home charger, plug it into my inverter, which is then plugged into a cigarette lighter outlet? (drawing from my truck battery). This would only be done while I was driving (got more than a few 12hr driving days)

I'd really prefer to get a DC-DC charger, but I am not willing to spend the cash on one till I decide on a more permanent set up wrt a second battery.

 

[pugslyyy]

I'll get right to the point: I'm departing on a month long trip soon, and will need a way to recharge my deep cycle. Would it work to bring my home charger, plug it into my inverter, which is then plugged into a cigarette lighter outlet? (drawing from my truck battery). This would only be done while I was driving (got more than a few 12hr driving days)

I'd really prefer to get a DC-DC charger, but I am not willing to spend the cash on one till I decide on a more permanent set up wrt a second battery.

It's inefficient, but if you are only doing it when driving then don't sweat it.

 

[jonyjoe101]

it should work, but there are some AC battery chargers that i encounter that don't work when plugged into an modified wave inverter, they might work with a more expensive pure sine inverter. I would test it before going on the trip.

You can also just connect to a 12 volt cigarette adapter and bypass the inverter, thats how some of the 12 volt jump packs are charged while driving. They use a male to male cord they sell at autozone. So technically you really dont need a dc to dc charger, since your just charging a 12 volt battery, from a 12 volt alternator, when the battery is full it wont accept any more amps.

 

[Chris Boyd]

Why not a battery selectors switch and some heavy duty fuses? Charge right from the alternator? You didn't mention why you'd need to have a DC-DC converter... Is the vehicle 24v?

High amperage from a cigarette lighter is never a good idea... They weren't designed for the constant draw and develop quite a bit of heat (the intended purpose).

If the battery you intend to charge isn't in the engine compartment, then I'd run a pair of cables (red/black wire, maybe 10 gauge from the battery to the location and stick a pair of andersons on it. Bonus is you run the inverter from it or connect directly to the battery (assuming it's 12v) Fuse the lines at the battery.

You can get Anderson power poles and red/black twin line from PowerWerx or somewhere similar.

 

[Walrus]

Thanks for the input everyone. I did some testing this afternoon and came to the conclusion that this not an ideal solution. The ideal solution would be a proper dual battery setup, but at this point I have not decided how I want to go about that. I could go the under-hood route, or build a tongue box for my kamparoo to house my fridge, my battery, and all associated equipment, or make my own power pack in a pelican case. The latter two would require a run to the rear of the truck anyways, so I think I'll just do that for now. Unfortunately my alternator output voltage is less than my battery's charging requirements. I've got a DC input LED driver with adjustable output voltage. I'll give that a run tomorrow and see how it works.