House Batteries Draining Fast in 2007 Winnebago Aspect 26A

[S.Rodimus]

We have a 2007 Winnebago Aspect 26A with two 12V car batteries connected together for powering the house things.
They are dated 2023 (but I don't know if that's a manufacture date, or an expiration date).

For reference, the status panel looks like this (not my photos -- I stole these from the Internet):

We went on a local camping trip this weekend, and despite starting with a fully-charged battery bank, they seemed to run down really quickly. We used power occasionally throughout the day for water pump/toilet flushing, and later that night had a 12V fan plugged into a 12V ("cell phone") outlet and 1 ceiling light on. After about an hour, the ceiling light started dimming, and lol and behold, the status panel displayed the batteries down to just the one red LED.

We flipped on the generator to re-charge, and within 15 minutes were back up to all four LEDs (red + yellow + 2 greens) illuminated again.

The next day, we didn't use much power (we thought). There was about 15 minutes of cooking using the fan over the stove plus a ceiling light. Then later that night, just ceiling lights on. And of course occasional water pump for the toilet throughout the day. Again, that night, our ceiling lights started dimming. The status panel showed 2 LEDs on (the bottom red + the yellow above it). The weird part this time was that once we turned everything off and waited a while, the panel reverted back up to showing 3 LEDs on (bottom red + yellow above that + one of the greens above that). The batteries seem to have recovered some just by turning everything off.

So, what do we think is going on here --

• Are the few things we used enough to really run the batteries down that far and/or that fast?
• Maybe the batteries just old and dying and can't hold a charge as long as they used to?
• Should the batteries (assuming they're healthy) have lasted longer under these conditions?
• Is that 2023 date on the batteries likely a manufacture or expiration date?

 

[Morich]

Can we assume these are lead acid batteries? If that is true, there are some things that need some explanation. They "may" be getting old but firstt hought is to check a few other things.
One big thing is how battery voltage is checked as well as how the power is used. We connect at the posts and read the voltage att eh same point and that can mislead us a great deal if we miss some points on how SLOW lead acid works.
In schools they try to explain this as much the same as looking in a hole att eh to of a barrel where we store something like really thick syrup. When we look in that hole as we are pouring in syrup (or charging?) we may see lots of syrup and if not thinking carefully we may think the barrel is full and stopadding syrup (charging).
That can mean we do not actually fill the barrel or battery and when we wait a while to come back and look in that hoe after nosyrup or charging for a while, we may find the syrup/charge has settled and the barrel may not be full at all!
Same happens with lead acid battteries that actually take around 6 hours or more if really run down load to get them back to fully charge! When you charge for an hour or les, it is much like looking at syrup through the hole and you may see lots but that is because there is a pile of syrup right att he hole, while most of the barrel is still empty! Come back in an hour and we find the barrel is actuallys till pretty close to empty!
Ona a battery, it is much the same, we may see lots of syrup but when we start taking that syrup/ charge out, there is not much in that tiny pile and it runs dry very quickly!
Surface charge is the techie term for this idea, if you want to do a search for more info.

And the way the lights went down and then came back are much the same problem of looking in a very small hole to try to figure out how much we have in that container.
We add charge in a very small spot and let it spread, which takes a lot of time. When we take the charge out it also takes it out of the small space, making it appear there is nothing in the battery. But if we give the slow moving stuff inside time to settle, it may fill in that hole and it looks like the container has more than when we stopped taking it out!
Semi-goofy way to describe it but helps to paint the visual picture of things we can't see!
Hard to get a good read on what power we have left if we don't stop adding or using power and let the batteries become stable or settle for an hour or so! Ane while camping, that is pretty hard to do as we often ARE using or adding power.

 

[Eagle5]

• Are the few things we used enough to really run the batteries down that far and/or that fast?
  • no
• Maybe the batteries just old and dying and can't hold a charge as long as they used to?
  • yes
• Should the batteries (assuming they're healthy) have lasted longer under these conditions?
  • Lead/Acid batteries must be recharged at least once-per-month or they can be permanently damaged. I leave my motorhome plugged-into a 120 VAC outlet all the time, which keeps the batteries healthy. My twin 12 VDC batteries (they are wired in parallel; not series) are 7½ years old and still running strongly.
• Is that 2023 date on the batteries likely a manufacture or expiration date?
  • It is the manufacturing date

Sorry, but I believe you must replace your batteries.
Eagle5

 

[S.Rodimus]

• ...My twin 12 VDC batteries (they are wired in parallel; not series) are ...

I'm no electrical expert, so maybe mine are in parallel, not series. I just know that they are connected correctly. I have revised my original post to remove that possible incorrect description.

 

[Morich]

Series will add the voltage of one to the other, so likely not using 24Volts and that makes them parallel! If you had gone to using something different like golf cart six volt batteries and wired them to get 12 volt you would have series!
But on how long batteries should last? That is a deep one with lots and lots of details to change the answer. I never get as long as I would like and I worked with lead acid batteries for a long time. The industrial batteries lasted 20 years but they also got tender loving care almost constanty! Huge cells that each cell was near two feet tall and designed to last a long time at near $200 per cell. Monitored full time, checked and watered /cleaned monthly and with tons of lead and acid in each string, they did last a long time!
Several things make out small batteries last far less as long. A big one is how little lead and acid there is in our setup. That also makes them much cheaper!
Things that age batteries are often things we may change a little bit but how much we are willing/able to do for what amount of savings on replacement is often the big question!
Letting them go low on charge is one big issue, but if we can't use them, how much value do we get? The lower the voltage goes, the more prone to damage and how long we leave them low is also a factor.
Letting them get low on water, especially if the plates begin to come out of the water, is a big factor to avoid. Cleaning the top to make sure there is not a trail of minerals across to some ground point like the strap that holds them is a biggie. But how much time/effort do we each actually want to spend to save the batteries? I find I wanted to do better but rarely did it! I hate battery work! UGH! If I never look at another one, I'm fine with that!
So we get over into options? Big expensive options work lots better but they ARE pricey until you reach that crisis point where you are willing to go that route! We never reached that point but many do go for it!
We grew up in the country and never valued being alone enough to want to bite that big bullet to avoid the crowd. We opted for going to the inbetween campsites we liked better. Not commercial but still with lots of things like running water and power!

A couple smaller points that you may want to consider? Try not to run them below an actual stable voltage of maybe 11 volts and recharge as soon as practical will help. Keep them clean and only use distilled water to top them off. Normal water has lots more minerals and as the water evaporates off, those minerals coat the lead plates and reduce the exposure to acid and that reduces usable lifespan. If the plates come out of the water, those minerals dry on them and you can kind of consider that part of the lead as lost! There are ways to try to restore the plates but not normally considered practical for most of us on the cheaper size we use.
And that can come back around to how long the batteries may last in different parts of the country! Temperature different and what is in the water are a couple that are easy to spot. If you live in Texas where it is not nice for a battery and the water is close to hard as the kitchen sink, batteries dies sooner than if in the North where is stays cooler to lose less water and limestone if not so common in water you might use to fill the battery! If you put a lot of limestone in as you add water and it stays when the water evaporates, it coats the lead and the battery dies sooner!

 

[Waterbug]

Yesterday, I made a post about pulse charging RV lead/acid batteries. The device costs about $14.00. Pulse charging batteries supposedly breaks down sulfate crystals that build up when batteries sit idle for long periods of time. It may be worth a shot. Can't do any harm and the device maintains battery charge when not in use. It will extend the life of your new batteries, should you need to replace them. EDIT: Lead/Acid Battery Maintenance 2012 Suncruiser 37F

 

[Morich]

I have to fully agree that the idea seems to be one to try at that price! I have a hard time imagining we can get that much electronics built into anything selling that low, but if it does, it would be a definite win.
But then it will not be a full cure for watching the batteries in many cases that depend on small points. We will still have to watch if we continue to use unsealed lead acid batteries.
One point is that they will go dry faster when we leave them on charge full time. How fast will change with all kinds of small situations. Higher temperatures during storage will make water evaporate quicker, so we each need to watch to see what is happening in our specific case. One way to damage these batteries is letting the lead plates come out of the water!
I found it worthwhile for me to replace the normal lead acid with AGM (absorbed glass mat) batteries as a way to reduce my battery care. I was willing to pay a slightly higher price when replacing them to allow for less work time on watching and watering them. The same for switching to distilled water instead of tap as I know the Central US water is often very high in limestone and magnesium. If the water has more junk in it to stick to the plates, they degrade sooner.

 

[S.Rodimus]

deleted comment, b/c I posted it on the wrong thread. sorry!