batteries in the winter

[Campinfan]

Ok, so another battery question. The motor home I may buy next week has 2 12 volt batteries in it, not that that makes a difference in my question. I will be storing my unit at home and have a pedestal with 30 amp service.(It was installed when a previous trailer was 30 amp). Over the winter I have some options. Should I leave the MH plugged in all winter and the batteries connected. If I do this, I have a new Battery Minder (not a battery tender that only trickle charges) that keeps the batteries from sulfating---should I attach that to the batteries too or or should I disconnect the batteries, and just use the battery minder. And if I do that, can I leave them in the rig or should I bring them in the house. I am thinking I should bring them in and use the battery minder.
I am open to suggestions. Thanks all.

[SuperBus]

Just to give another point of reference, I leave all eight (8) batteries in the coach (onboard smart charger/inverter) and it is always plugged in, year-round.  No issues I can attribute to that practice.

[trailmeisterjoe]

Years ago I added a Charge Wizzard to the system and it automatically monitors battery health and regularly desulphates them too. RV is pluged in always and have had zero issues for years. My last 4 trojan 6 volts lasted 12 years.

[Flapper]

bgum wrote:

KD4UPL wrote:
Turn off your battety disconnect and just leave the batteries in the MH. No nred for a charger as there is no discharge. If they won't hold a charge all winter disconnected they need replacing.

I consider this to be incorrect information as they can loose up to 5% charge per month.

Here;s the chart I trot out, from "Battery University" when the subject comes up:

https://batteryuniversity.com/img/content/storage-web-corrected.jpg

As one can see, the colder the average temp, the longer they can be left before self discharge is a concern. Over the winter in the north, no issue. I'd think hard about long term over the summer in Texas or Arizona, however...

[Campinfan]

Great information from all of you. wa8yxm---loved the last line in your post. The motorhome I may be buying next week is a 2019 so I am sure it is a better converter.

[wa8yxm]

Leave it plugged in? Depends on your converter. MOST modern converters you can do that safely.

Some older (Kind of last century) not such a good idea.

Disconnect when fully charged.. Usually save and by disconnect I mean Disconnect physically at the battery not the USE/STORE or other switch but physically break the connection.

Tender.. that's a good option if you have one of those older battery killer converters.

Fully charged battery is good to around the point where you need not ask C or F.. that's -40 in case you wonder.

[JRscooby]

bgum wrote:

KD4UPL wrote:
Turn off your battety disconnect and just leave the batteries in the MH. No nred for a charger as there is no discharge. If they won't hold a charge all winter disconnected they need replacing.

I consider this to be incorrect information as they can loose up to 5% charge per month.

How much damage is done, at what % of charge? And how long is winter?
By my limited math skills that would mean still over 80% after 4 months.

[JKJavelin]

I have a couple collector cars, and for years, all I do is disconnect the positive cable for winter storage in Wisconsin. No charging or special treatment or heated garage. Reconnect them in the spring and crank em up. Never a problem and those batteries last for years and years.
My fifth wheel has solar, so it all stays connected year round.
JK

[bgum]

Latner wrote:

bgum wrote:

KD4UPL wrote:
Turn off your battety disconnect and just leave the batteries in the MH. No nred for a charger as there is no discharge. If they won't hold a charge all winter disconnected they need replacing.

I consider this to be incorrect information as they can loose up to 5% charge per month.

Big temperature shift from South Louisiana and Michigan this time of year. Temperature affects how fast a battery discharges, faster in warm weather, slower in cold weather. My boat sits in Michigan from Oct. to April with the battery sitting in it just disconnected, never a problem.

Never thought to look where he is located. Right you are. If I did that I would have to buy new batteries every year.

[Latner]

bgum wrote:

KD4UPL wrote:
Turn off your battety disconnect and just leave the batteries in the MH. No nred for a charger as there is no discharge. If they won't hold a charge all winter disconnected they need replacing.

I consider this to be incorrect information as they can loose up to 5% charge per month.

Big temperature shift from South Louisiana and Michigan this time of year. Temperature affects how fast a battery discharges, faster in warm weather, slower in cold weather. My boat sits in Michigan from Oct. to April with the battery sitting in it just disconnected, never a problem.

[bgum]

KD4UPL wrote:
Turn off your battety disconnect and just leave the batteries in the MH. No nred for a charger as there is no discharge. If they won't hold a charge all winter disconnected they need replacing.

I consider this to be incorrect information as they can loose up to 5% charge per month.

[RLS7201]

There is no reason to remove the batteries for winter. If you have a smart charger/inverter then just plug in and check the water once or twice during the winter. If you only have a one stare charger, put a timer on its power cord and set it for 2 hours a day.
My coach is plugged in during the winter and the batteries only come out when needing to be changed. Kip It Simple..........

Richard

[TenOC]

I would keep them plugged to shore power so that they are fully charged. I think (?) SULFATING only happen if less than fully charged and high temp

[KD4UPL]

Turn off your battety disconnect and just leave the batteries in the MH. No nred for a charger as there is no discharge. If they won't hold a charge all winter disconnected they need replacing.

[midnightsadie]

my rv sit,s in a pole bldg coach plugged in eng battery on a tender,do nothing with coach batteries. meter says 13.3 thats ok with me.