Can you charge a car battery through the cigarette lighter

I'd like to put a solar panel behind the windshield to maintain the battery. Would that work? I can think of two possible obstacles, but I don't know whether either is real:
1. The cigarette lighter circuit gets cut off, say, 10 minutes after shutting off the engine to avoid unnecessary energy drains to the battery, or
2. The circuit has a 12v voltage regulator on it, and so there's no way to feedback 13.5v+ back to the battery.

Are there any obstacles, such as these or others, that are in the way of doing it?

The cigarette lighter would be convenient, but if it's hopeless for this, is there some other circuit I could tap into at the fuse box that would work? i.e.I'd like to avoid drilling a hole in the firewall and running a dedicated wire.

If it matters: my Durango is a 2005 HEMI Limited. Drives like a champ.. I'm shocked to see so little current forum activity. Well, here I am, a beacon shining into the darkness. Hopefully somebody else is still out there!

1. No, but you would need to ensure it was a constant 12v source and not a keyed one.
2. You don't understand how voltage regulation works in your vehicle; there is no voltage regulator. That function is handled by the PCM.
It will work just fine, just make sure you get it in a good spot. I had a little one I got from Harbor freight plugged into the socket to trickle charge my battery on deployments because I couldn't trust my ex-wife to run it on a consistent enough basis and I got tired of coming back to dead batteries.

I got some from Ebay that had cigarette lighter plugs on them, they were used on VW and others when they got shipped over here.

1. No, but you would need to ensure it was a constant 12v source and not a keyed one.
2. You don't understand how voltage regulation works in your vehicle; there is no voltage regulator. That function is handled by the PCM.
It will work just fine, just make sure you get it in a good spot. I had a little one I got from Harbor freight plugged into the socket to trickle charge my battery on deployments because I couldn't trust my ex-wife to run it on a consistent enough basis and I got tired of coming back to dead batteries.

Thanks! I've confirmed that the dashboard cig lighter doesn't have power after the engine is switched off, BUT the power outlet located within the armrest has non-interrupted power without any need for the key to be in the ignition. Now I just need to confirm that I can charge the battery from that location, which, from what you seem to be saying, should be possible.

Battery Tender makes a solar charge controller for this type of application: Battery Tender® 5-45W Automatic Solar Controller
It sounds a bit primitive, as I don't believe it is MPPT capable, but if I'm otherwise able to harvest enough sunlight it won't matter.

Reporting back: I confirmed that solar charging is definitely possible (and works!) through the 12v plug located inside the armrest comparment.

It will through the constant 12v. This is the one I used for 2yrs: 1.5 Watt Solar Battery Charger

Well, the price is certainly right on that one. I'd prefer to have an amorphous panel anyway, which that one is. Where did you mount it? Is a 1.5 watt solar charger really powerful enough to keep your battery topped off? Seems like the charging current would be, at best, only around 100ma, and that only for a portion of the day.

Left it right on the dashboard lol. Started every time after 2 months or so.

Left it right on the dashboard lol. Started every time after 2 months or so.

What voltage are you able to keep on your battery using just it?

What voltage are you able to keep on your battery using just it?

Haven't used it in 7yrs, but the answer is "enough" . I never measured it. It did what I needed it to.

I posted a detailed follow-up, but it looks as though the post got lost or else never made it.

Anyhow, I had taken some measurements, and going from memory now, my 2005 Durango LTD consumes about 16 milliamps from the battery while it sits doing nothing, but that jumps up briefly about once per second to roughly double current that if the Durango is also "armed". I hadn't measured how long that higher current pulse lasts.

However, just charging the battery at a constant rate of around 16+ milliamps won't be enough to keep the battery floating at maximum, because of self discharge. From a charging point of view, the number that matters will be the self-discharge rate plus the 16 or so milliamps the Durango draws from the battery. It probably varies by battery model, and I'm guessing it maybe differs somewhat between two batteries of the same model. It probably also varies depending on the health of the battery. Nonetheless, it would be nice to have at least one solid measurement to refer to. Hence, I'll make an attempt sometime soon to measure my fairly new Interstate Group 65 battery's self-discharge rate and report back here on what it is.

Reporting back: The self-discharge on the Costco Interstate battery, when fully charged to 13.8v, is 220 milliamps. This completely dwarfs the 20-30 or so milliamps that the Durango consumes while sleeping.