House Battery Blues? - Page 2

boywonder · 09-18-2016, 01:37 PM

Quote:

Originally Posted by MountainBikeRoamer

>>> I'm still in the middle of making sense of whether or not my house battery is in fact sealed (and thus, not able to be tested with a battery hydrometer.)

If it's a wet cell, it's highly likely that the caps come off even if they look like they don't......

Sounds like the battery is not fully charged....

I doubt you have a short anywhere.....and the alternator isn't exactly a smart charger though. Do you have the recommended absorb and float charge voltages for the battery?

Do you have a battery separator or isolator? Isolators inherently drop about .7V due to the forward diode drop in them. That can result in a not fully topped off condition....

Do you have anything that resembles a "smart" (multi-mode) charger that you can fully charge the battery with?

Feel free to stop by if you want....I have a few basic meters to check stuff, nothing fancy.....I'm in Coto De Caza

larrie · 09-18-2016, 01:57 PM

This thread got me thinking about my new wet cell deep cycle Trojan batteries. Went to their site and poked around a bit to find their maintenance page. Lots of good information. Very near the bottom it talks about discharging and watering the battery. They recommend 50% or less discharge before recharging. They also say 80% discharge is the maximum before damaging the battery.

The watering section has two great photos water level.

There are also some tips on maximizing battery life.

MountainBikeRoamer · 09-18-2016, 01:59 PM

Quote:

Originally Posted by boywonder

If it's a wet cell, it's highly likely that the caps come off even if they look like they don't......

Sounds like the battery is not fully charged....

I doubt you have a short anywhere.....and the alternator isn't exactly a smart charger though. Do you have the recommended absorb and float charge voltages for the battery?

Do you have a battery separator or isolator? Isolators inherently drop about .7V due to the forward diode drop in them. That can result in a not fully topped off condition....

Do you have anything that resembles a "smart" (multi-mode) charger that you can fully charge the battery with?

Feel free to stop by if you want....I have a few basic meters to check stuff, nothing fancy.....I'm in Coto De Caza

Hey thanks boywonder!!!

I believe you're right.
Looks like two rectangular snapped-in-place caps that can be removed to check the cells.

To your questions:
Don't know the recommended "float" or "absorb" charges for this battery. How would I go about determining those? (As in, are those readily identified on a spec sheet when you purchase an RV/Marine battery?)

Also --
I don't have a "smart" charger. Sounds like that's an item worth looking into.
And as far as the battery isolator, yes --- it's equipped with the one that SMB built into it when they outfitted the rig in 1995, but I don't know it's specs.

For what it's worth....
The battery in the van now is the third one that's been in there since I bought the van.....and all three have been the identical make/model of battery. Shortly after buying the van, I went and found (as a drop-in replacement) the exact-same battery as the van came with from its previous owner, reasoning that it was probably the safest bet as far as "matching specs" for the electrical system my van had. And I felt I kind of *had* to replace the battery that the van came with, as it was over six years old and clearly wasn't recharging/holding charge very well at all.

The second battery (the first "brand new" one) worked wonderfully for two years until just recently. Didn't display any of the weird sudden-voltage-drop behavior that this newest battery is showing, right out of the box. And nothing else has changed in my system as of late, other than dropping in this new battery to remedy the slowly-ailing old one.

------------------------------------------------
More learning:

(For anyone else learning about maintenance of 12V wet-cell batteries like myself, I found this to be a pretty great (and short!) youtube video on how to access/test the cells (and refill them with distilled water, if any are low.))

Checking battery acid levels

https://www.youtube.com/watch?v=NS6phSxHlC0

**daveb** · 09-18-2016, 02:04 PM

If you have a true wet cell deep cycle battery and you've never check the water level, the chances are high one of the cells has been exposed and killed the battery. These type of wet cell batteries vent and require monitoring the water level above the plates. I used standard wet cell type deep cycle batteries in bass boats over the years. I hated keeping an eye on the water levels. Wet cell is a multiple term though...AGM and typical maintenance free automotive are usually considered wet cell types. They just all have slight differences on how they're designed, used, maintained and charged. Here is a good link on batteries:
https://www.solar-electric.com/deep-...tery-faq.html/

MountainBikeRoamer · 09-18-2016, 02:12 PM

Quote:

Originally Posted by daveb

If you have a true wet cell deep cycle battery and you've never check the water level, the chances are high one of the cells has been exposed and killed the battery. These type of wet cell batteries vent and require monitoring the water level above the plates. I used standard wet cell type deep cycle batteries in bass boats over the years. I hated keeping an eye on the water levels. Wet cell is a multiple term though...AGM and typical maintenance free automotive are usually considered wet cell types. They just all have slight differences on how they're designed, used, maintained and charged. Here is a good link on batteries:
https://www.solar-electric.com/deep-...tery-faq.html/

Thanks Dave!
I now understand how indicating it's a "wet cell" battery is not truly indicative of exactly which type of battery it is.

For what it's worth --- I had meant "lead acid" wet cell, but now I wanted to be super sure that was indeed correct.....so I went just now and double (triple) checked, and found the MSDS chemical content page for the battery in question:

It's a standard (old-school) lead-acid.
(And I should re-state this.....it's seriously only about a month old. Brand-new battery.)

**daveb** · 09-18-2016, 02:28 PM

Hey, maybe you got a lemon. How long was it on the shelf? Was it stored fully charged? Is it a factory defect? Bad connection? There are a host of things that can be causes including something after the battery pulling it down. If you can get to the cell covers, a visual once over is recommended and then a hydrometer test. Unequal or low reading often point to a bad battery. An amp check will give you an idea about load and should be done after checking the battery.
My point is do the easy stuff first. Everything posted so far in this thread is right on. It could be a short although when you posted the link to the battery you had it threw up a red flag in my mind. I'd hate to see you do a bunch of unnecessary work. But if you have a "open" cell type deep cycle mounted in an inaccessible spot, consider a AGM type.

BTW those load testers work pretty good...you can rent one if necessary but as mentioned most part stores may loan or test your battery on site.

86Scotty · 09-18-2016, 02:38 PM

I hate to open this can of worms even further but I just caught that you have a 95 with the original isolator. I'm not necessarily thinking this is part of your problem, but for best results you might want to replace it soon. There are a lot more stable, durable and reliable ones nowadays. My 95 that I sold recently was still using it's original blue heat-sync type but that was an anomoly. Twogone's 95 died and I've heard of many others having the original older ones go. Once again, I'm not sure if that could contribute to your current problem but I wouldn't rule it out. Scalf77, Dave and others will probably know.

boywonder · 09-18-2016, 03:06 PM

Quote:

Originally Posted by MountainBikeRoamer

To your questions:
Don't know the recommended "float" or "absorb" charges for this battery. How would I go about determining those? (As in, are those readily identified on a spec sheet when you purchase an RV/Marine battery?)

I don't have a "smart" charger. Sounds like that's an item worth looking into.
And as far as the battery isolator, yes --- it's equipped with the one that SMB built into it when they outfitted the rig in 1995, but I don't know it's specs.

The float and absorb specs for the battery are somewhere....

Have you confirmed that you have an isolator and not a separator, ie looked at it? Since your van is a 1995, it's quite likely that you have an isolator....replacing that with a separator may help with battery state of charge. All that being said, there are plenty of folks around with isolators, although many of them may also have smart chargers and/or solar controllers to fully top off the battery.

**daveb** · 09-18-2016, 04:02 PM

Even a typical automotive charger will bring the battery up to about 80%, so if it's disconnected, fully charged and then left unhooked, most of the time a bad battery will self discharge itself overnight after the charge is removed. A load tester or any higher amp load can be applied to test it and see how fast it drops. That will rule out if the van has an issue provided you find the battery can't hold a charge.
The isolators setup SMB used back in the day were prone to corrosion and would sometimes leak current to ground. For it to kill a battery that fast I'd think it would be a higher amp fault. But as in all electrical trouble shooting, there might be a series of issues leading to what seems to be one problem.

After inspecting the battery, provided you see no issues, I would pull the leads, charge it with a battery charger, see if it holds a charge (even a 10A car charger is good enough to test with), let it sit disconnected overnight and do the load test and/or the hydrometer test. Mess with the van stuff after that. Put it back in service if it passed the battery tests and do an amp check. There may be slight draw from things like the stereo but all of those shouldn't provide a high amp reading.

Poor battery maintenance is the main killer of batteries. Within 2 months? Maybe. I did think you stated the charge voltage was reaching 14+ volts. Where the port is that you're taking voltage matters as well. If it's one of the stock ports up front (ahead of the isolator) chances are the voltage you saw may have been off the starter battery. It's possible the isolator isn't passing through the necessary voltage/current to keep the levels up over the last few month. That is where you need to ditch the pluggy thing and use a real voltmeter (on the battery during the testing). My thoughts still point to a dry cell but a combination of problems may have led to its death.
Hard to tell w/o actually being there.

MountainBikeRoamer · 09-18-2016, 04:18 PM

Okay thanks everyone. Been digesting everything you've been throwing out (and at) me.

Currently doing initial battery testing and sleuthing.

Of note so far:

1) I noted that the battery dropped overnight (just sitting in the driveway!) from 12.8 (when I parked it last night) to a measured/indicated 12.5 volts when I checked it just 20 minutes ago.

I checked this two ways, by the way --- by both observing the cheap-o plug-in-the-wall voltage meter, and also by ***directly testing the current across the terminals of the battery itself.*** Both numbers were very close....12.5 volts.

I'm running the van right now to charge the battery back up, aiming for 20-30 minutes of idling (as I've done in the past) and hoping to get a good resting voltage of 12.8 volts from which I can start doing some load testing hopefully.

Also:
2) I investigated the "isolator vs. separator" question --- I've definitely got an isolator. Photos here:

Is this indeed an original-looking isolator for this van? And something that is worth considering to replace based on its age, regardless, with a more modern separator of some sort?

Will report back with the measured resting voltage of the battery after it's "charged." (As measured by both on-the-terminal testing and by the "wall-socket-o-matic" plug-in cheapie voltage meter.)