Battery charging through cig lighter

I'm pretty comfortable with just using clamps. Leaving the car in accessory, in order to use the cig lighter outlet, seems kinda pointless.

 

What's wrong with leaving the hood up and charging through the jump terminal in the fuse box?

 

With our infrequent use this is how ours looks as often as not.

 

You run an extension cord to your car in the rain?

 

You could tuck a compact charger under the hood, run just the cord out. There's a few point along the edge of the hood were it's doable I think.

 

If you purchase a "Battery Tender" or other battery maintainer, they usually come with several types of "pigtails", intended to be installed in the car, ATV, or motorcycle you intend to use them on. Installing one of these in the underhood fusebox is easy and recommended rather than trying to leave the car "on" in whatever state needed to charge from the accessory power outlet. Most of these battery maintainers are small, and easily fit underhood. You can close the hood on them. You can even leave them under there when driving and simply use the "block heater" type plugin arrangement (plug hanging out the grill to be used when needed). DO ensure you properly affix them if you intend to leave them under there. Drivers side is best, far from the exhaust heat.

 

The thing is that if you have to leave the system in ACC-ON for the outlet to be connected, then that in itself is putting a load on the 12V AuxBattery which means it would be charging and discharging simultaneously (I realize that it would work, but it's rather inefficient). I used the pigtail with the rings on (red -> positive terminal in fuse-box, and black -> nearby ground point) - photos (if needed) to come later!

 

It isd

It is my understanding that all the computers which control the system use 12V (it's the same reason that the system will not "start" if the 12V AuxBattery is dead) - I'm not sure of exactly how much current the system (computers etc. etc.) need to operate, I'm just sayin' - that's all!

 

Similar solution here. 8 year old battery in my Prius which has been driven maybe 1/month the last 4 months due to COVID work from home was dead...couldn't unlock the car with the key FOB. 11.2V on diag display, 11.8 after full over-night charge with NOCO G3500. Replaced battery and have ordered a solar trickle charger (POWOXI 3.3W-Solar-Battery-Trickle-Charger-Maintainer), but alas, can't use the cigarette lighter and don't want to try to get under the dash to rewire it (which I did fairly easily in my old Camry). So while replacing the battery, just put terminals on some spare 16AWG speaker wire, connected it to the terminals of the battery, and ran it under the seats & carpet to come up under the passenger seat. When the solar trickle charger arrives, I'll figure out some way to splice a connecter on the end of the speaker wire to the solar charger.

Cheers!
p.s. Navy AQ1(AW)

 

Did you manage to find a way to do this? My Prius (14 yr old) regularly has a dead battery from being used v irregularly and while I think it's probably time for a new battery, I would like to fit a permanent solar trickle charger.

I park on the street so running anything out of the bonnet won't work.

Funnily enough my partner is a LCDR too. Just about to try and sort his car out so its ready for when he gets back from sea.