Battery charge from truck

[EVMIII]

Picked up camper today after a month at the dealer service shop, battery was run down below capability to operate Lippert sytem. About 10 minutes hooked to truck and it had enough juice to lift the legs so I could hookup and tow. About an hour to the tire shop and a quick check on camper and it was still low. Not as low as before, plenty to unhook and autolevel, enough to power panel to test (would not initially) but not fully charged. My test guage crapped out so I can't tell specific charge. My question is how long should it take the truck to full re charge depleted batteries?

[chuckster57]

Depends on how many amps your alternator is, how discharged the battery is and how many batteries.

[bobbecky]

Your tow vehicle's alternator is not designed to recharge a dead battery. You should use either the trailer converter which requires the trailer to be plugged into a power source, or you could use a battery charger. With the battery that far discharged, it's not capable of storing as much power as when new. You may be better off replacing the battery.

[NorskeBob]

It is all about amp-hours.

If you have consumed 50-ampere-hours from a 100-amp hour battery - At a 10-amp, charging rate, it should take approximately 4.3 hours to get to a 90% state-of-charge.

I would check the electrolyte (water) level in the battery after recharging.

[sourdough]

I think my thoughts have already been posted;

When was the last time you checked the water in the battery and how often have you done that? In addition to the things mentioned, the time to recharge will also depend greatly on the overall condition of the battery. If you do replace the battery be sure and replace all of them at the same time if you have multiple batteries.

[EVMIII]

Thanks for the replies. Battery cells were just topped off a couple weeks ago, but I'll definitely check them when the batteries are fully charged. Trailer is on shore power now and seems to be charging. I'll keep an eye on it this evening and will be replacing my voltmeter tomorrow.

[dcg9381]

Amp hours and battery condition. Keystone doesn't install true battery disconnects, my guess is that a lot of new owners get surprised with dead batteries that eventually won't take a decent charge anymore.

You can pull the battery and have them "tested" at most Autozone locations.

Get a disconnect (true disconnect) if you don't have one yet.