Camper Van Winter Storage

[dustytrailhead]

I would like opinions on how to store my camper van for the winter.

Situation: Near Seattle, WA at about 400 ft. elevation. Weeklong temps below freezing not uncommon seasonally, but not frequent.

Equipment:
2 100ah Renogy Smart Lithium (w/ “shelf mode”, low temp disconnect)
Renogy DCC50S MPPT/D2D charger
PV: 480 watts (3 x 160w, parallel)
All components have breakers/switches

Questions:
Can I leave the system connected?
What are the points of failure?
Should I disconnect all the batteries, house and chassis?

 

[ianganderton]

Lifepo4 doesn’t have a discharge over time problem in the way lead acid does so I’d ensure it was charged to about 80% and disconnect it completely. That way no little mysterious ghost load can flatten it while it’s stored

 

[dustytrailhead]

From your response, I assume disconnecting the house batteries is a foregone conclusion. I was hoping to just leave the system activated all winter until spring when I’m back…but never mind. Ok, stuff can still happen, so it’s better to be safe than sorry. I’ll flip all the switches and open the breakers on the “house” side, and then disconnect the chassis battery.
One day maybe house battery systems will be reliable enough that they can manage extreme weather events and component failures unattended without self-destructing. Until that happy day I will disconnect.

 

[ianganderton]

From your response, I assume disconnecting the house batteries is a foregone conclusion. I was hoping to just leave the system activated all winter until spring when I’m back…but never mind. Ok, stuff can still happen, so it’s better to be safe than sorry. I’ll flip all the switches and open the breakers on the “house” side, and then disconnect the chassis battery.
One day maybe house battery systems will be reliable enough that they can manage extreme weather events and component failures unattended without self-destructing. Until that happy day I will disconnect.

By your chassis battery are you meaning the one that powers your starter motor?

What chemistry is it? Is it lead acid?

Problem with lead acid is it discharges even if disconnected (5% a month I think, depends on temperature and how old it is). I'd want to plug that in to a battery maintainer or trickle charger of some sort

 

[dustytrailhead]

Yes, starter battery. I’m not sure, but I was wondering if the MPPT/D2D would maintain the starter battery. I know it sends charge to the starter battery when it’s low, but I don’t know what triggers it. Anyway, there’s no power. It’s just a parking spot between other campers in storage. Would be nice to leave everything on, but I’m pretty sure the lithiums will be safer if they’re disconnected. Starter batteries are cheap. But, I have a friend who leaves his car parked for a few months. He just disconnects the starter battery. He’s never had a problem.

 

[dirt diggler]

Yes, starter battery. I’m not sure, but I was wondering if the MPPT/D2D would maintain the starter battery. I know it sends charge to the starter battery when it’s low, but I don’t know what triggers it. Anyway, there’s no power. It’s just a parking spot between other campers in storage. Would be nice to leave everything on, but I’m pretty sure the lithiums will be safer if they’re disconnected. Starter batteries are cheap. But, I have a friend who leaves his car parked for a few months. He just disconnects the starter battery. He’s never had a problem.

The DCC50S only charges the starter battery when the house battery is over 13.9 (mine takes 5 seconds to trigger) so you'd need the/a house battery in to trigger it, i swap in a FLA over winter and change the DCC to the FLA settings, then i just leave everything on as normal.
Having said that my battery is easy to get at and swap as i built it that way cos i use the Lith battery in another application during the winter (indoors).

 

[GooseF16]

could he just swap the starter battery lead to the Primary, remove house Batt and set to FLA?..

I say that but my truck( rear power for charging model airplanes) I just put a very low power PV trickle in the window direct to the starter batt, and removed anything thats temp sensitive..

my MH is a different story tho.. it has self heated batteries.. Lithionics 320s.. so they keep themselves warm if you can keep them charged.. they kick on below 35deg.. so I keep the solar full up and running until the snow gets heavy.. it can last about a week or two before it is depleted, so that one needs babysitting unless I shut it down altogether, which I plan to do at first heavy snow, with the batts down a little bit. and bring em back as soon as I can after big snow season.. maybe a couple months..

 

[dirt diggler]

I have a small 20W panel in the windscreen of evey vehical i own, they don't do a lot but off setting the self discharge/BMS load is enough for me