To Plug or Not to Plug

DocMP · 11-26-2018, 03:40 PM

Forgive if this is a silly question: How important is it to keep the house battery in my 2012 Ford SMB fully charged at all times? The former owner had a sweet garage with 220v outlet just for the van. Right now my rig is on the driveway, and the solar panels are getting sun most days, but the van is not plugged into shore power. Thinking about renting a garage for it (won't fit in current garage, of course), but difficult finding a garage rental with power access. So do I need to plug it in?

BrianW · 11-26-2018, 03:59 PM

I take my batteries out when I store it for the winter and put them on trickle charge in my garage.

rnj · 11-26-2018, 07:02 PM

Just to clarify I think it was a 120V 30A AC outlet. If it was 220V all 120V electrical items in the van would have been fried. From reading rv forums a 220V dryer outlet looks the same but is wired differently. You do not want to plug into 220V.

**rionapo** · 11-26-2018, 07:47 PM

Can you run an extension cord to it? My understanding is battery life is determined by recharge cycles but there are others on the forum who know if this is correct.

Don

Bbasso · 11-26-2018, 07:59 PM

Your solar system can do the job (keeping the batteries topped off) just fine IF the math is correct.

Orv · 11-26-2018, 11:36 PM

If there's no load on them you really only need to keep up with the self-discharge rate. Solar panels should do it. If you're parked in a garage with power a 120V "battery tender" (aka trickle charger) would be ideal. Sometimes if the garage has an overhead incandescent light you can cheat and use an adapter that screws into the light fixture and adds two electrical sockets.

Depending on what converter you have, keeping the van plugged in all the time might even overcharge the batteries and shorten their life. Mine seems to run at 14.3V, which is far too high for a long-term 'float' charge.

Mostly you want to avoid having them sit there in a fully discharged condition, which can sulfate the plates and even result in the battery freezing. BrianW's suggestion is a good one. When I had to store a van for the winter in a place with no power, I took the battery with me and kept it on a battery tender at home.

If none of these options work for you, disconnect the cables (to avoid parasitic loads) and they'll probably retain most of their charge through the winter. You're taking a risk, but worse case you need to replace the batteries sooner.

rltilley · 12-02-2018, 10:35 AM

My van has sat outside since I picked it up in late 2012. The two solar panels on top keep the batteries topped off without me having to plug the van in. I do live in SoCal which helps with having adequate sun for the solar.

Beasty Boy · 12-02-2018, 11:34 AM

Dont'cha just love batteries

Vehicles,flashlights,remotes,alarms,WHATEVER,
constantly F***in withem

I wish some genius would come up with
something better

flyfisher · 12-02-2018, 01:04 PM

I have a 2005 SMB with a Lifeline AGM for the house battery. I talked to the folks at Lifeline and they recommend keeping the battery plugged in and charged if possible.

AdventureDave · 12-02-2018, 01:14 PM

You don't say what type of batteries you have. I will assume they are AGM. You definitely want to keep the batteries fully charged while not in use. You should check the specs on your solar charge controller. It may or may not be a smart charger that monitors the charge state and changes the charge voltage input accordingly. Most importantly does it have a trickle charge mode? You definitely do not want to keep a full charge voltage going to the batteries all the time either.